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Sample records for maleic anhydride modified

  1. Enhancement of Adhesion between EPDM and Polyester Fabric by Using Natural Rubber Modified by Maleic Anhydride

    Directory of Open Access Journals (Sweden)

    A. A. El-Wakil

    2011-01-01

    Full Text Available This study presents a new method for improving adhesion between ethylene propylene diene monomer (EPDM rubber and polyester fabric. In this work, natural rubber was modified by maleic anhydride in order to improve the adhesion force between ethylene propylene diene monomer rubber and polyester fabric. The effect of thermal aging and ionizing radiation on the stability of the rubber mix as well as on the peel strength of the rubber-coated fabric was investigated. It was observed that the natural rubber modified by maleic anhydride improved the peel strength of the EPDM rubber-coated polyester fabric.

  2. Synthesis and Characterization of a Novel Biomaterial:Maleic Anhydride-modified Poly(dl-lactic acid)

    Institute of Scientific and Technical Information of China (English)

    Yan Feng LUO; Yuan Liang WANG; Xu Feng NIU; Jun PAN; Liang Ping SHI

    2004-01-01

    A novel modified poly(dl-lactic acid) (PDLLA) was obtained by covalently grafting of maleic anhydride onto the backbone of PDLLA, attempting to improve PDLLA's hydrophilicity and cell affinity and to provide reactive groups for further chemical modification. FTIR, 13C NMR and DSC were used to characterize the maleic anhydride-modified PDLLA.

  3. PDMS-modified poly(styrene-alt-maleic anhydride)s as water-borne coatings based on surfactant-free latexes

    NARCIS (Netherlands)

    Gunbas, I.D.; Wouters, M.E.L.; Benthem, R.A.T.M. van; Koning, C.E.; Noordover, B.A.J.

    2013-01-01

    In this work, two series of PDMS-modified poly(styrene-alt-maleic anhydride)s (PSMA) were prepared by the partial imidization of their anhydride groups with mono-functional, amine-terminated polydimethyl siloxanes (PDMS-NH2) with two different molecular weights. Subsequently, surfactant-free artific

  4. Physicochemical Characterization and the Comparison of Chitin and Chitin Modified with Maleic Anhydride

    Directory of Open Access Journals (Sweden)

    İlhan Uzun

    2015-06-01

    Full Text Available Firstly, chitin was modified via ring-opening reaction with maleic anhydride in lithium chloride/N,N-dimethylacetamide. Then, both chitin and chitin modified with maleic anhydride (CMA were characterized by Fourier transform infrared (FTIR spectroscopy, X-ray diffraction (XRD method, ultraviolet-visible (UV-Vis spectroscopy, and scanning electron microscopy (SEM. Thermogravimetric analysis (TGA was performed to investigate the thermal stability of chitin and CMA. TGA results showed that chitin is thermally more stable than CMA. In addition, the electrical conductivity of chitin and CMA was also measured. Electrical conductivity measurement results showed that the electrical conductivity of CMA (4.3x10-4 S cm-1 is more than that of chitin (6.5x10-6 S cm-1.

  5. Effect of surface modified kaolin on properties of polypropylene grafted maleic anhydride

    Science.gov (United States)

    Yang, Ni; Zhang, Zuo-Cai; Ma, Ning; Liu, Huan-Li; Zhan, Xue-Qing; Li, Bing; Gao, Wei; Tsai, Fang-Chang; Jiang, Tao; Chang, Chang-Jung; Chiang, Tai-Chin; Shi, Dean

    To achieve reinforcement of mechanical and thermal performances of polypropylene (PP) product, this work aimed at fabrication of surface modified kaolin (M-kaolin) filled polypropylene grafted maleic anhydride (PP-g-MAH) composites with varying contents of fillers and investigation of their mechanical and thermal properties. And the prepared PP-g-MAH/M-kaolin composites were characterized by means of Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). Fracture analysis by SEM showed M-kaolin particles were well dispersed in the PP-g-MAH matrix. Mechanical behaviors were determined by tensile strength, tensile strain at break and impact strength analysis. Impact strength of PP-g-MAH/2 wt% M-kaolin composites was improved up to 30% comparing with unfilled composites. Thermostability had been found enhanced when M-kaolin added. The results revealed PP-g-MAH/M-kaolin composites showed the optimal thermal and mechanical properties when 2 wt% of M-kaolin was added.

  6. Samarium-modified vanadium phosphate catalyst for the selective oxidation of n-butane to maleic anhydride

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Hua-Yi [State Key Laboratory of Physical Chemistry of Solid Surfaces, National Engineering Laboratory for Green Chemical Productions of Alcohols, Ethers and Esters, and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005 (China); Wang, Hai-Bo [Fushun Res InstPetr& Petrochem, Fushun, 113001 (China); Liu, Xin-Hua; Li, Jian-Hui; Yang, Mei-Hua [State Key Laboratory of Physical Chemistry of Solid Surfaces, National Engineering Laboratory for Green Chemical Productions of Alcohols, Ethers and Esters, and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005 (China); Huang, Chuan-Jing, E-mail: huangcj@xmu.edu.cn [State Key Laboratory of Physical Chemistry of Solid Surfaces, National Engineering Laboratory for Green Chemical Productions of Alcohols, Ethers and Esters, and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005 (China); Weng, Wei-Zheng [State Key Laboratory of Physical Chemistry of Solid Surfaces, National Engineering Laboratory for Green Chemical Productions of Alcohols, Ethers and Esters, and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005 (China); Wan, Hui-Lin, E-mail: hlwan@xmu.edu.cn [State Key Laboratory of Physical Chemistry of Solid Surfaces, National Engineering Laboratory for Green Chemical Productions of Alcohols, Ethers and Esters, and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005 (China)

    2015-10-01

    Graphical abstract: The addition of a small amount of Sm into VPO catalyst brought about great changes in its physicochemical properties such as surface area, surface morphology, phase composition and redox property, thus leading to a higher catalytic performance in the selective oxidation of n-butane to maleic anhydride, as compared to the undoped VPO catalyst. - Highlights: • The addition of Sm leads to great changes in the structure of VPO catalyst. • Sm improves performance of VPO for oxidation of n-butane to maleic anhydride. • Catalytic performance is closely related to structure of VPO catalyst. - Abstract: A series of samarium-modified vanadium phosphate catalysts were prepared and studied in selective oxidation of n-butane to maleic anhydride. The catalytic evaluation showed that Sm modification significantly increased the overall n-butane conversion and intrinsic activity. N{sub 2}-adsorption, XRD, SEM, Raman, XPS, EPR and H{sub 2}-TPR techniques were used to investigate the intrinsic difference among these catalysts. The results revealed that the addition of Sm to VPO catalyst can increase the surface area of the catalyst, lead to a significant change in catalyst morphology from plate-like structure into rosette-shape clusters, and largely promote the formation of (VO){sub 2}P{sub 2}O{sub 7}. All of these were related to the different catalytic performance of Sm-doped and undoped VPO catalysts. The roles of the different VOPO{sub 4} phases and the influence of Sm were also described and discussed.

  7. Intranasal Administration of Maleic Anhydride-Modified Human Serum Albumin for Pre-Exposure Prophylaxis of Respiratory Syncytial Virus Infection

    Directory of Open Access Journals (Sweden)

    Zhiwu Sun

    2015-02-01

    Full Text Available Respiratory syncytial virus (RSV is the leading cause of pediatric viral respiratory tract infections. Neither vaccine nor effective antiviral therapy is available to prevent and treat RSV infection. Palivizumab, a humanized monoclonal antibody, is the only product approved to prevent serious RSV infection, but its high cost is prohibitive in low-income countries. Here, we aimed to identify an effective, safe, and affordable antiviral agent for pre-exposure prophylaxis (PrEP of RSV infection in children at high risk. We found that maleic anhydride (ML-modified human serum albumin (HSA, designated ML-HSA, exhibited potent antiviral activity against RSV and that the percentages of the modified lysines and arginies in ML- are correlated with such anti-RSV activity. ML-HSA inhibited RSV entry and replication by interacting with viral G protein and blocking RSV attachment to the target cells, while ML-HAS neither bound to F protein, nor inhibited F protein-mediated membrane fusion. Intranasal administration of ML-HSA before RSV infection resulted in significant decrease of the viral titers in the lungs of mice. ML-HSA shows promise for further development into an effective, safe, affordable, and easy-to-use intranasal regimen for pre-exposure prophylaxis of RSV infection in children at high risk in both low- and high-income countries.

  8. PHOTOCOPOLYMERIZATION OF MALEIC ANHYDRIDE AND VINYL ACETATE

    Institute of Scientific and Technical Information of China (English)

    LI Xiaofang; LI Shanjun; QIN Anwei; YU Tongyin

    1990-01-01

    The charge-transfer complex of maleic anhydride and vinyl acetate was copolymerized under UV light. The chain composition and structure of the copolymer were analyzed with conductometry and NMR, and the chain sequence was determined as alternating. The copolymerization rates at different feed ratios, temperatures and in different solvents were investigated, giving evidence to the very active involvement of the CT complexes in the copolymerization. Terpolymerization with acrylonitrile also showed that the complex mechanism was a proper one for this system.

  9. PRELIMINARY STUDY OF EXTRACTABLE PROTEIN BINDING USING MALEIC ANHYDRIDE COPOLYMER

    Institute of Scientific and Technical Information of China (English)

    Thirawan Nipithakul; Ladawan Watthanachote; Nanticha Kalapat

    2012-01-01

    A preliminary study of using maleic anhydride copolymer for protein binding has been carried out.The polymeric films were prepared by compression of the purified resin and annealing the film to induce efficient back formation of the anhydride groups.The properties of the film surface were analyzed by attenuated total reflection Fourier transforms infrared spectroscopy and water contact angle measurements.The protein content was determined by Bradford assay.To obtain optimum conditions,immersion time for protein binding was examined.Results revealed that proteins can be successfully immobilized onto the film surface via covalent linkage.The efficiency of the covalent binding of the extractable protein to maleic anhydride-polyethylene film was estimated at 69.87 μtg/cm2,although the film had low anhydride content (3%) on the surface.

  10. Resonance energy transfer from quinolinone modified polystyrene-block-poly(styrene-alt-maleic anhydride) copolymer to terbium(III) metal ions

    Energy Technology Data Exchange (ETDEWEB)

    Výprachtický, Drahomír, E-mail: vyprachticky@imc.cas.cz [Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Heyrovský Sq. 2, 162 06 Prague 6 (Czech Republic); Mikeš, František [New York University Polytechnic School of Engineering, Polymer Research Institute, 6 MetroTech Center, Brooklyn, NY 11201 (United States); Lokaj, Jan; Pokorná, Veronika; Cimrová, Věra [Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Heyrovský Sq. 2, 162 06 Prague 6 (Czech Republic)

    2015-04-15

    Polystyrene-block-poly(styrene-alt-maleic anhydride) was synthesized by nitroxide mediated radical polymerization and modified with 7-amino-4-methylquinolin-2(1H)-one (I) and methanol. The formed block polymer ligand contained a quinolinone fluorophore (Ω) and carboxyl (III) or sodium carboxylate (IV) binding sites. The ligand-to-metal resonance energy transfer (RET) and ligand binding properties of [III–Tb{sup 3+}] and [IV–Tb{sup 3+}] complexes were investigated by steady-state and time-resolved luminescence spectroscopy in tetrahydrofuran/methanol and/or tetrahydrofuran/deuterated methanol mixtures and compared with those of a low-molecular-weight model ligand, i.e. the sodium salt of N-(4-methyl-2-oxo-1,2-dihydroquinolin-7-yl)succinamic acid (II). The long-lived emission intensities of Tb{sup 3+} at 490, 545, 585, and 620 nm corresponding to the {sup 5}D{sub 4}→{sup 7}F{sub 6}, {sup 5}D{sub 4}→{sup 7}F{sub 5}, {sup 5}D{sub 4}→{sup 7}F{sub 4}, and {sup 5}D{sub 4}→{sup 7}F{sub 3} transitions, respectively, were strongly increased by the addition of ligands in the order [II-Tb{sup 3+}]⪡[III-Tb{sup 3+}]<[IV-Tb{sup 3+}]. The efficiency of energy transfer (E) was evaluated from the emission intensity of the donor (Ω) in the presence or absence of the acceptor (Tb{sup 3+}) depending on the acceptor concentration and ligand neutralization. It was concluded that the macromolecular ligand structural properties (polymer coil and supramolecular structures, e.g. micelles) were responsible for the increase in RET. The time-resolved luminescence measurements revealed that the binding affinity of the ligands II, III, and IV increased in the order IImodified block polymer (donor) for Tb{sup 3+} (acceptor) luminescence was developed. • Efficient donor–acceptor resonance energy transfer (RET) was found out. • Macromolecular (polymer coil) structure caused a powerful RET and also a supramacromolecular (micelles) structure

  11. Particleboard made from waste paper treated with maleic anhydride.

    Science.gov (United States)

    Nourbakhsh, Amir; Ashori, Alireza

    2010-01-01

    This study evaluates the usage of waste newspaper as a supplement raw material for laboratory-made single-layer particle-boards. The boards were made of various ratios (75/25, 50/50, 25/75 and 0/100) of waste paper flakes to wood particles mixtures (wt/wt). The effects of press temperature and maleic anhydride on the properties of the boards were determined. Evaluated properties were modulus of rupture, modulus of elasticity, internal bonding strength, and thickness swelling. Panels made from waste newspaper satisfied the modulus of rupture, modulus of elasticity and internal bonding strength requirements of European Norms standards. Performing a statistical analysis of the results, press temperature and maleic anhydride content were found to be positively effective on the mechanical properties at a 95% confidence level. The results from this study indicated that technically waste paper could be a potential substitute material for particleboard manufacture.

  12. Interaction and release of catechin from anhydride maleic-grafted polypropylene films.

    Science.gov (United States)

    López de Dicastillo, Carol; Castro-López, Maria Del Mar; Lasagabaster, Aurora; López-Vilariño, Jose M; González-Rodríguez, M Victoria

    2013-04-24

    In this paper, investigations were carried out on catechin-loaded maleic anhydride (MAH)-modified polypropylenes (PP). Two maleic-modified polypropylenes (PPMAH) with different maleic concentrations have been blended with PP and catechin to obtain composites of improved catechin retention with the aim of studying the possible interactions between these grafted polymers with antioxidants, and a secondary interest in developing an active antioxidant packaging. Composite physicochemical properties were measured by thermal analysis (thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and oxidation induction time (OIT)) and infrared spectroscopy studies. Catechin release profiles into food simulants were obtained by HPLC-PDA-QqQ, following European legislation. Antiradical activity of composites was analyzed by the ABTS and DPPH method. The formation of intermolecular hydrogen bonds between catechin and functionalized PP has been confirmed by Fourier transform infrared (FTIR) studies. Besides, a small fraction of ester bonds, formed as a result of a chemical reaction between a fraction of the hydrolyzed anhydride and the catechin hydroxyl groups, is not discarded. OIT results also showed an increase in antioxidant effectiveness caused by the presence of catechin- and maleic-modified PPMAH in the blend formulations. Incorporation of MAH-grafted PP increased substantially the retention rate of catechin, being dependent on the MAH content of the grafted polypropylene. The described interactions between catechin and maleic groups, together with changes in PP morphology in comparison with reference PP explained lower antioxidant release. Besides formulation, antioxidant release was dependent on the type of food, the temperature, and the time.

  13. POLYMERIC IONIC CONDUCTORS MODIFIED WITH POLAR GROUPS: PART Ⅱ. STRUCTURE-IONIC CONDUCTION RELATION IN LI-COMPLEX BASED ON MALEIC ANHYDRIDE- COPOLYMERIZED METHACRYLATES

    Institute of Scientific and Technical Information of China (English)

    XU Kang; ZHOU Tong; DENG Zhenghua; WAN Guoxiang

    1992-01-01

    Ringlike polar monomer maleic anhydride (MAn) was copolymerized with oligo (oxyethylene)methacrylate (MEOn), and its effect on ion conduction property of the corresponding polymer-salt complexes was studied. As a consequence the introduction of MAn onto polymer chain retards crystallization of the ether pendants considerably, and improves the ion conductivity to a larger degree compared with other polar groups once investigated (σmax,25 ℃ = 8.5 × 10-5 S/cm). The structure-ion conduction relation in the polymer- salt matrix is also analyzed macroscopically through the correspondence between composition-dependences of polymerization conversion and isothermal ion conductivity, and microscopically through the measurements of cross polarized light and electron transmission.

  14. Preparation and characterization of poly(styrene/maleic anhydride)/kaolin nanocomposites

    Institute of Scientific and Technical Information of China (English)

    LIU Xuening; ZHANG Hongtao; YANG Zhizhong; HA Chengyong

    2005-01-01

    The direct exfoliation of in situ intercalative copolymerized styrene/maleic anhydride charge-transfercomplex (PSMA) into the inter lamellar spaces of modified kaolin (Kao-DMSO), which was intercalated and surface modified by dimethyl sulfoxide (DMSO), was reported. The nano structure of the composites was investigated by wide-angle X-ray diffraction (XRD) and transmission electron microscopy (TEM). The interaction between kaolin surface and PSMA chain was conformed by FTIR analysis. The XRD results showed that the intercalated polystyrene-maleic anhydride units were arranged in the flattened monolayer arrangements, and the 001 diffraction peak of the original kaolin disappeared. The TEM image showed that the kaolin was exfoliated into nanometer size and dispersed in the polymer matrix. Additionally the thermal stability of the nanocomposites was studied by thermo-gravimetric analysis (TGA), and the resulting thermogram indicated that the thermal stability of the nanocomposites was significantly increased.

  15. Preparation of maleic anhydride modified cassava lees/PVC wood plastic composites%马来酸酐改性木薯酒糟/PVC木塑复合材料制备

    Institute of Scientific and Technical Information of China (English)

    覃宇奔; 胡华宇; 张燕娟; 覃杏珍; 蒋婷; 杨梅; 黄爱民; 黄祖强; 罗袁伟

    2014-01-01

    This study focused on the preparation of cassava lees/PVC wood plastic composites ( WPC) by solid phase blending modification.Cassava lees/PVC WPC were prepared by hot press molding technology using cassava lees as reinforced material, PVC as polymer matrix, maleic an-hydride as modifier, internal mixer as synchronous mixing equipment, and plate vulcanizing press as plate-pressing machine.The effects of hot press temperature, pressure, time, dosage of maleic an-hydride, etc.on the properties of the composites were investigated, and the feasibility of synchronous modification of cassava lees and PVC by maleic anhydride was also discussed.The results show that under the conditions of cassava lees content 50%, hot press temperature 180 ℃, pressure 6 MPa, time 7.5 min, and the dosage of maleic anhydride of 1%, the bending strength and tensile strength of the cassava lees/PVC composite were 26.1 MPa and 11.1 MPa, respectively, meeting the re-quirements of the basic mechanics indexes of the composites.The addition of calcium zinc compound heat stabilizer could effectively improve the mechanical properties of the composites.With the dosage of heat stabilizer of 0.8%, the bending strength and tensile strength increased by 7.7% and 19.8%, respectively.Our results indicated that cassava lees and PVC could be modified synchronously by maleic anhydride in solid phase process, which improved the adhesion between fiber and polymer matrix and effectively enhanced the mechanical properties of WPC.%为研究固相共混改性法制备木薯酒糟/PVC木塑复合材料的工艺,探讨马来酸酐同步改性木薯酒糟和PVC的可行性,以木薯酒糟为增强原料,PVC为聚合物基体,马来酸酐为改性剂,密炼机为同步混炼设备,平板硫化机为压板机,采用热压成型技术制备酒糟/PVC木塑复合材料,研究热压成型温度、压力、时间、马来酸酐用量等因素对板材力学性能的影响。结果表明:在酒糟填充量50%

  16. Process of cleaning phthalic and maleic anhydrides from gases

    Energy Technology Data Exchange (ETDEWEB)

    Pavlovich, L.B.; Karbainov, A.D.; Morozkina, N.A.; Smokotin, N.E.; Syskin, V.A.

    1981-01-02

    A process is described for cleaning phthalic and maleic anhydrides from gases by oxidation of them at elevated temperature on a catalyst, being characterized by the fact that with the aim of simultaneously cleaning 1,4-naphthoquinone from the gases and simplifying the process, a vanadium slag of the following composition is used as the catalyst: (wt%) MnO 8-9, U/sub 2/O/sub 5/ 13-19, Tio 9-10 A1/sub 2/O/sub 3/ 1-4, Cr/sub 2/O/sub 3/ 7-9, phosphorus 0.05-0.1, SiO/sub 2/ 15-25, CaO 1.0-2.0, Mgo 0.5-1.5; FeO the remainder. The process can be used for catalytic cleaning from gases of organic substances, for example waste gases from phthalic anhydride production.

  17. Properties of Esterified Wood Prepared with Maleic Anhydride / Tetrabr Omophthalic Anhydride / Glycerol Mixture

    Institute of Scientific and Technical Information of China (English)

    Li Jianzhang; Furuno Takeshi; Zhou Wenrui; Yu Zhiming; Sun Yanling; Zhang Derong

    2003-01-01

    For overcoming disadvantages of wood, an esterification process was employed and tetrabromophthalic anhydride (TBPA) was used as a reactive chemical agent to prepare an esterified wood with the high dimensional stability, flame resistance, and resistance to biodegradation from water-leaching. The experimental results indicated that esterification of wood plus maleic anhydride / tetrabromophthalic anhydride / glycerol could endow wood with dimensional stability, the antiswelling efficiency during water absorption (ASEw), reduction in water absorptivity (RWA), antiswelling efficiency during moisture absorption (ASEm), moisture excluding efficiency (MEE), and oxygen index (OI) of treated wood increased with an increase in the weight percent gain (WPG). And the treated wood showed great decay resistance and resistance to water leaching, too.

  18. Synthesis and Characterization of Poly(maleic Anhydride)s Cross-linked Polyimide Aerogels

    Science.gov (United States)

    Guo, Haiquan; Meador, Mary Ann B.

    2015-01-01

    With the development of technology for aerospace applications, new thermal insulation materials are required to be flexible and capable of surviving high heat flux. For instance, flexible insulation is needed for inflatable aerodynamic decelerators which are used to slow spacecraft for entry, descent and landing (EDL) operations. Polyimide aerogels have low density, high porosity, high surface area, and better mechanical properties than silica aerogels and can be made into flexible thin films, thus they are potential candidates for aerospace needs. The previously reported cross-linkers such as octa(aminophenyl)silsesquioxane (OAPS) and 1,3,5-triaminophenoxybenzene (TAB) are either expensive or not commercially available. Here, we report the synthesis of a series of polyimide aerogels cross-linked using various commercially available poly(maleic anhydride)s, as seen in Figure 1. The amine end capped polyimide oligomers were made with 3,3,4,4-biphenyltetracarboxylic dianhydride (BPDA) and diamine combinations of dimethylbenzidine (DMBZ) and 4, 4-oxydianiline (ODA). The resulting aerogels have low density (0.12 gcm3 to 0.16 gcm3), high porosity (90) and high surface area (380-554 m2g). The effect of the different poly(maleic anhydride) cross-linkers and polyimide backbone structures on density, shrinkage, porosity, surface area, mechanical properties, moisture resistance and thermal properties will be discussed.

  19. Evaluation of copolymer conformation states of vinylchloride-maleic anhydride

    Science.gov (United States)

    Ivanov, A. A.

    2016-11-01

    The quantum-chemical analysis and experimental study of alternating vinylchloride-maleic anhydride (VC-MA) copolymer macromolecules with polymerization degree 600 have been carried out. The VC-MA copolymer in solvents of different nature undergoes cycloanhydride-enol tautomerism and the macromolecules take the form of corrugated sticks according to viscometric measurements. The computer simulation has shown that the segment with polymerization degree n < 18 (model compound) is not a helix and rolls while if n = 18 the conformations get distorted. The model molecule optimal structure comprising a random sequence of alternating units of comonomers and their enol tautomers with minimal system total energy has been found by the semiempirical parametric method PM3.

  20. Electrospun mats from styrene/maleic anhydride copolymers: modification with amines and assessment of antimicrobial activity.

    Science.gov (United States)

    Ignatova, Milena; Stoilova, Olya; Manolova, Nevena; Markova, Nadya; Rashkov, Iliya

    2010-08-11

    New antimicrobial microfibrous electrospun mats from styrene/maleic anhydride copolymers were prepared. Two approaches were applied: (i) grafting of poly(propylene glycol) monoamine (Jeffamine® M-600) on the mats followed by formation of complex with iodine; (ii) modification of the mats with amines of 8-hydroxyquinoline or biguanide type with antimicrobial activity. Microbiological screening against S. aureus, E. coli and C. albicans revealed that both the formation of complex with iodine and the covalent attachment of 5-amino-8-hydroxyquinoline or of chlorhexidine impart high antimicrobial activity to the mats. In addition, S. aureus bacteria did not adhere to modified mats.

  1. 40 CFR 721.6183 - Amides, from ammonium hydroxide - maleic anhydride polymer and hydrogenated tallow alkyl amines...

    Science.gov (United States)

    2010-07-01

    ... - maleic anhydride polymer and hydrogenated tallow alkyl amines, sodium salts, compds. with ethanolamine... Substances § 721.6183 Amides, from ammonium hydroxide - maleic anhydride polymer and hydrogenated tallow... anhydride polymer and hydrogenated tallow alkyl amines, sodium salts, compds. with ethanolamine (PMN...

  2. Grafting of poly (lactic acid) with maleic anhydride using supercritical carbon dioxide

    Science.gov (United States)

    Khankrua, R.; Pivsa-Art, S.; Hiroyuki, H.; Suttiruengwong, S.

    2015-07-01

    The aim of this work was to modify poly lactic acid (PLA) via free radical grafting with maleic anhydride (MA) by using supercritical carbon dioxide (SCCO2). Benzoyl peroxide (BPO) was used as an initiator. The solubility of MA in SCCO2 was first determined to estimate the suitable grafting conditions and equilibrium. From the solubility study of MA in SCCO2, it was found that the solubility of MA in SCCO2 increased with the increasing pressure and dissolution time. PLA films were first prepared by compression molding. The ratio of MA to BPO was 2:1. The reaction temperature and pressure were 70°C and 100 bar respectively. The grafting reaction and the degree of grafting were characterized by nuclear magnetic resonance (NMR) spectroscopy and titration, respectively. Scanning electron microscope (SEM) technique and contact angle were used to confirm the changes in physical properties of PLA film grafted MA. NMR spectrum indicated that the grafting of MA onto PLA was successively achieved. Degree of grafting by using SCCO2 was as high as 0.98%. This provided rather high grafting degree compared with other processes. SEM pictures showed the rough surface structure on modified PLA film. In addition, contact angle results showed an improvement of the hydrophilicity by maleic anhydride grafting onto polymers.

  3. MALEIC ANHYDRIDE HYDROGENATION OF PD/AL2O3 CATALYST UNDER SUPERCRITICAL CO2 MEDIUM

    Science.gov (United States)

    Hydrogenation of maleic anhydride (MA) to either y-butyrolactone of succinic anhydride over simple Pd/Al2O3 impregnated catalyst in supercritical CO2 medium has been studied at different temperatures and pressures. A comparison of the supercritical CO2 medium reaction with the c...

  4. Investigation of Plasma Polymerized Maleic Anhydride Film in a Middle Frequency Dielectric Barrier Discharge

    Institute of Scientific and Technical Information of China (English)

    TANG Wenjie; CHEN Qiang; ZHANG Yuefei; GE Yuanjing

    2008-01-01

    Plasma polymerized maleic anhydride (MA) was carried out by using maleic anhydride supersaturated ethanol solution as a precursor in a dielectric barrier discharge (DBD). The film properties were characterized by water contact angle (WCA), Fourier transfer infrared (FTIR), X-ray photoelectron spectroscopy (XPS), atomic force microscope (AFM) analysis, and a thickness profilometer. The influence of the processing parameters on the film properties such as the power frequency, and polymerization zone was investigated. The results show that anhydride group incorporated into the growing films is favorable at the frequency of 80 kHz and working pressure of 50 Pa. The poly (maleic anhydride) film is uniform and compact at an average deposition rate of 8 nm/min.

  5. Selective oxidation of carbon monoxide in the presence of butane and maleic anhydride

    Energy Technology Data Exchange (ETDEWEB)

    Corbin, D.R.; Bonifaz, C. (DuPont Company, Wilmington, DE (United States))

    1994-03-01

    The selective oxidation of carbon monoxide in the presence of butane and maleic anhydride has been studied over platinum- and palladium-containing zeolites as well as palladium-on-silica (Pd/SiO[sub 2]) catalysts. The results show that although a zeolite support is needed in many systems to effect a kinetic control to improve selectivity, thermodynamic control using Pd([approximately]2-4 ppm)/SiO[sub 2] is sufficient to give the desired selectivities in this system. In addition, a palladium-containing vanadium-phosphate catalyst was prepared that showed complete oxidation of carbon monoxide, conversion of butane to maleic anhydride, and no observable decomposition of the maleic anhydride. 14 refs., 4 tabs.

  6. Crystal structure of 2,3-di-methyl-maleic anhydride: continuous chains of electrostatic attraction.

    Science.gov (United States)

    Wiscons, Ren A; Zeller, Matthias; Rowsell, Jesse L C

    2015-08-01

    In the crystal structure of 2,3-di-methyl-maleic anhydride, C6H6O3, the closest non-bonding inter-molecular distances, between the carbonyl C and O atoms of neighboring mol-ecules, were measured as 2.9054 (11) and 3.0509 (11) Å, which are well below the sum of the van der Waals radii for these atoms. These close contacts, as well as packing motifs similar to that of the title compound, were also found in the crystal structure of maleic anhydride itself and other 2,3-disubstituted maleic anhydrides. Computational modeling suggests that this close contact is caused by strong electrostatic inter-actions between the carbonyl C and O atoms.

  7. Solvent-free esterification of poly(vinyl alcohol) and maleic anhydride through mechanochemical reaction

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A solid-state mechanochemical processing, that is, pan-milling, was used to conduct the esterification of poly(vinyl alcohol)(PVA) with maleic anhydride (MA) through stress-induced reaction. FTIR spectrum study indicated the presence of ester linkages and olefinic double bonds in maleic anhydride cross-linked PVA. Thermal properties of the cross-linked product were characterized by DSC. The results showed its glass transition temperature was 20 ℃ higher than the original linear PVA and the thermal stability was also improved.

  8. Graft Copolymers of Maleic Anhydride and Its Isostructural Analogues: High Performance Engineering Materials

    OpenAIRE

    Rzayev, Zakir M. O.

    2011-01-01

    This review summarizes the main advances published over the last 15 years outlining the different methods of grafting, including reactive extruder systems, surface modification, grafting and graft copolymerization of synthetic and natural polymers with maleic anhydride and its isostructural analogues such as maleimides and maleates, and anhydrides, esters and imides of citraconic and itaconic acids, derivatives of fumaric acid, etc. Special attention is spared to the grafting of conventional ...

  9. THE GRAFTING OF MALEIC-ANHYDRIDE ON HIGH-DENSITY POLYETHYLENE IN AN EXTRUDER

    NARCIS (Netherlands)

    GANZEVELD, KJ; JANSSEN, LPBM

    The grafting of maleic anhydride (MAH) on high density polyethylene in a counter-rotating twin screw extruder has been studied. As the reaction kinetics appear to be affected by mass transfer, good micro mixing in the extruder is important. Due to the competing mechanisms of increasing mixing and

  10. THE GRAFTING OF MALEIC-ANHYDRIDE ON HIGH-DENSITY POLYETHYLENE IN AN EXTRUDER

    NARCIS (Netherlands)

    GANZEVELD, KJ; JANSSEN, LPBM

    1992-01-01

    The grafting of maleic anhydride (MAH) on high density polyethylene in a counter-rotating twin screw extruder has been studied. As the reaction kinetics appear to be affected by mass transfer, good micro mixing in the extruder is important. Due to the competing mechanisms of increasing mixing and de

  11. 21 CFR 872.3500 - Polyvinylmethylether maleic anhydride (PVM-MA), acid copolymer, and carboxymethylcellulose sodium...

    Science.gov (United States)

    2010-04-01

    ...), acid copolymer, and carboxymethylcellulose sodium (NACMC) denture adhesive. 872.3500 Section 872.3500...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3500 Polyvinylmethylether maleic anhydride (PVM-MA), acid copolymer, and carboxymethylcellulose sodium (NACMC) denture adhesive. (a) Identification...

  12. Maleic anhydride based copolymer dispersions for surface modification of polar substrates

    NARCIS (Netherlands)

    Gunbas, I.D.; Wouters, M.E.L.; Hendrix, M.M.R.M.; Benthem, R.A.T.M. van; Koning, C.E.; Noordover, B.A.J.

    2012-01-01

    In this article, we report the modification of poly(styrene-alt-maleic anhydride) (PSMA) with monofunctional amine-terminated poly(dimethyl siloxane) (PDMS-NH2) by thermal imidization, followed by the preparation and characterization of a surfactant-free artificial latex thereof and application of t

  13. Blends of Styrene-Butadiene-Styrene Triblock Copolymer with Random Styrene-Maleic Anhydride Copolymers

    NARCIS (Netherlands)

    Piccini, Maria Teresa; Ruggeri, Giacomo; Passaglia, Elisa; Picchioni, Francesco; Aglietto, Mauro

    2002-01-01

    Blends of styrene-butadiene-styrene triblock copolymer (SBS) with random styrene-maleic anhydride copolymers (PS-co-MA), having different MA content, were prepared in a Brabender Plastigraph mixer. The presence of polystyrene (PS) blocks in the SBS copolymer and the high styrene content (93 and 86 w

  14. Maleic anhydride based copolymer dispersions for surface modification of polar substrates

    NARCIS (Netherlands)

    Gunbas, I.D.; Wouters, M.E.L.; Hendrix, M.M.R.M.; Benthem, R.A.T.M. van; Koning, C.E.; Noordover, B.A.J.

    2012-01-01

    In this article, we report the modification of poly(styrene-alt-maleic anhydride) (PSMA) with monofunctional amine-terminated poly(dimethyl siloxane) (PDMS-NH2) by thermal imidization, followed by the preparation and characterization of a surfactant-free artificial latex thereof and application of

  15. Selective hydrogenation of maleic anhydride over Pd/Al2O3 catalysts prepared via colloid deposition

    Indian Academy of Sciences (India)

    Hongjing Yuan; Chunlei Zhang; Weitao Huo; Chunli Ning; Yong Tang; Yi Zhang; Dequan Cong; Wenxiang Zhang; Jiahuan Luo; Su Li; Zhenlu Wang

    2014-01-01

    Pd/Al2O3 catalysts were prepared via colloid deposition and the performance of the catalysts was examined in the selective hydrogenation of maleic anhydride to succinic anhydride. When the reaction was carried on in a batch system with 1,4-dioxane as the solvent (353K and 1.0MPa), high conversion of maleic anhydride (>98%) and high selectivity (>99%) for succinic anhydride were observed after 5 h. The as-prepared Pd/Al2O3 catalyst also showed excellent performance in solvent-free system and fixed-bed systems. The maleic anhydride (MA) conversion was greater than 98%, and high selectivity (>99%) for succinic anhydride was obtained after 1600 h in a fixed bed reacter. The results showed that the activity of the Pd/Al2O3 catalysts was excellent due to its high active surface area.

  16. Controlled Release of Damascone from Poly(styrene-co-maleic anhydride-based Bioconjugates in Functional Perfumery

    Directory of Open Access Journals (Sweden)

    Andreas Herrmann

    2013-02-01

    Full Text Available Poly(styrene-co-maleic anhydrides were modified with poly(propylene oxide (PO-co-ethylene oxide (EO side chains (Jeffamine® with different EO/PO molar ratios, varying between 0.11 and 3.60. These copolymers were then further functionalized with a β-mercapto ketone of δ-damascone. The obtained poly(maleic acid monoamide-based β-mercapto ketones were then studied as delivery systems for the controlled release of δ-damascone by retro 1,4-addition. The release of δ-damascone, a volatile, bioactive molecule of the family of rose ketones, was studied by dynamic headspace analysis above a cotton surface after deposition of a cationic surfactant containing fabric softening formulation, as a function of the ethylene oxide (EO/propylene oxide (PO molar ratio of the grafted copolymer side chains. The polarity of the EO/PO side chain influenced the release efficiency of the damascone in a typical fabric softening application. PO-rich copolymers and the corresponding poly(styrene-co-maleic anhydride without Jeffamine® side chains were found to be less efficient for the desired fragrance release than the corresponding bioconjugate with a EO/PO ratio of 3.60 in the side chain. This copolymer conjugate seemed to represent a suitable balance between hydrophilicity and hydrophobicity to favor the release of the δ-damascone and to improve the deposition of the conjugate from an aqueous environment onto a cotton surface.

  17. Radical coupling of maleic anhydride onto graphite to fabricate oxidized graphene nanolayers

    Indian Academy of Sciences (India)

    Fatemeh Samadaei; Mehdi Salami-Kalajahi; Hossein Roghani-Mamaqani

    2016-02-01

    Radical coupling was used to modify graphite with maleic anhydride (MAH). Azobisisobutyronitrile (AIBN) as radical generator activated MAH radically and it was reacted with defects at the surface of nanolayers. A set of batches with different reaction times (24, 48 and 72 h) were performed to obtain fully-modified nanolayers (GMA1, GMA2 and GMA3, respectively). Fourier transform infrared results approved the synthesis of MAHgrafted graphite. Thermogravimetric analysis showed that 5.9, 11.1 and 13.2 wt% of MAH was grafted onto the surface of GMA1, GMA2 and GMA3, respectively, and that was approved by X-ray photoelectron spectroscopy results. Also, X-ray diffraction patterns showed that $d$-spacing increased from 0.34 nm for graphite to 1.00 nm for all modified samples. However, GMA1 showed a weak peak related to graphite structure that disappeared when reaction time was increased. After modification with MAH, lamella flake structure of graphite was retained whereas the edges of sheets became distinguishable as depicted by scanning electron microscopy images. According to Raman spectra, modification progression resulted in more disorder structure of nanolayers due to grafting of MAH. Also, transmission electron microscopy images showed graphite as transparent layers while after modification, surface of nanolayers became folded due to the opposite effects of $\\pi$-conjugated domains and electrostatic repulsion of oxygen-containing groups.

  18. A new process for the valorisation of a bio-alcohol. The oxidehydration of 1-butanol into maleic anhydride

    Energy Technology Data Exchange (ETDEWEB)

    Caldarelli, A.; Cavani, F.; Garone, O.; Pavarelli, G. [Bologna Univ. (Italy). Dipt. di Chimica Industriale e dei Materiali; Bologna Univ. (Italy). CIRCC, Research Unit; Dubois, J.L. [ARKEMA, Colombes (France); Mitsova, I.; Simeonova, L. [JSC, Russe (Bulgaria). Orgachim

    2012-07-01

    This paper deals with a study on the gas-phase transformation of 1-butanol into maleic anhydride, using different types of catalysts. Indeed, catalytic acid properties are needed to dehydrate 1-butanol into 1-butene, whereas redox-type properties are required for the oxidation of the olefin into maleic anhydride. The two types of active sites can be combined in bifunctional systems, showing both acid and redox-type properties. We found that vanadyl pyrophosphate catalyzes the one-pot reaction, giving a maximum selectivity to maleic anhydride of 28%. In fact, various side reactions contributed to the formation of by-products, eg, 1-butanol (oxidative) dehydrogenation into butyraldehyde, formation of light carboxylic acids and carbon oxides, and condensation of unsaturated C{sub 4} intermediates (butenes and butadiene) with the formed maleic anhydride to yield heavier compounds. (orig.)

  19. Preparation and characterization of porous titania-grafted poly(styrene-divinylbenzene)/maleic anhydride nanocomposite microspheres

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Mesoporous titania-grafted poly(styrene-divinylbenzene)/maleic anhydride [P(St-DVB)/MA] nanocomposite microspheres were prepared by an open ring reaction method.The titania nanoparticles were first modified by attachment of amino groups to their surface to prevent particle aggregation,and to allow the nanoparticles to covalently bond the polymer microspheres,the surface of which was modified by attachment of MA functional groups to enable the polymer to retain their porous structures and to react with the amino groups on the surface of the titania particles.The porous nanocomposite microspheres were detected by FTIR,SEM,TEM,XRD and UV-Vis spectrophotometry.The results indicated that the nanocomposite microspheres were composed of nanosized titania uniformly distributed on the surface,and exhibited better UV absorbing property than pure polymer microspheres or unmodified titania.Furthermore,compared with pure porous polymer microspheres,the nanocomposite microspheres showed more efficient UV protection and slow release of Parsol-1789(a photo-reactive and cosmetic agent) held inside the porous network of the microspheres.

  20. Preparation and Mechanical Properties of Chitosan-graft Maleic Anhydride Reinforced with Montmorillonite

    Science.gov (United States)

    Fajrin, A.; Sari, L. A.; Rahmawati, N.; Saputra, O. A.; Suryanti, V.

    2017-02-01

    The research aims to develop biodegradable composites as bio-based plastics from chitosan. The composites were prepared via solution casting method by introducing the maleic anhydride (MAH) as grafting agent and montmorillonite (MMt) as reinforcement. The grafting process of chitosan was conducted by varying concentrations of MAH which were 10, 20, and 30% w/w. It was observed that the chitosan-graft-maleic anhydride (Cs-g-MAH) containing 10% w/w of MAH increased its tensile strength by 70%. Reinforcement material was added to the Cs-g-MAH by varying MMt concentrations, e.g. 3, 6, 9 and 12% w/w. It was noted that the presence of 9% w/w of MMt in the Cs-g-MAH gave the best mechanical properties of the Cs-g-MAH/MMt composite.

  1. Wheat Gluten Blends with Maleic Anhydride-Functionalized Polyacrylate Cross-Linkers for Improved Properties.

    Science.gov (United States)

    Diao, Cheng; Xia, Hongwei; Parnas, Richard S

    2015-10-14

    A family of polyacrylate-based cross-linkers was synthesized to maximize the toughness of high Tg, high modulus wheat gluten blends in the glassy state. Mechanical testing and damping measurements were conducted to provide an example where the work of fracture and strength of the blend substantially exceeds polystyrene while maintaining flexure stiffness in excess of 3 GPa. The new rubbery cross-linkers, polymethyl acrylate-co-maleic anhydride and polyethyl acrylate-co-maleic anhydride, improve WG mechanical properties and reduce water absorption simultaneously. MDSC, FTIR, HPLC, and NMR data confirmed the cross-linking reaction with wheat gluten. Flexural, DMA, and water absorption testing were carried out to characterize the property improvements. DMA was conducted to investigate the relationship between energy damping and mechanical property improvement. If the cross-linker damping temperature is close to the testing temperature, the entire sample exhibits high damping, toughness, and strength.

  2. Wet Strength and Antibacterial Performance of Cellulosic Paper Induced by Maleic Anhydride-Acylated Chitosan

    OpenAIRE

    Zicheng Chen,; Chunting Li; Zhanqian Song,; Xueren Qian

    2014-01-01

    Paper sheets were dipped in maleic anhydride-acylated chitosan (MAAC) to enhance their wet strength and antibacterial performance. The wet strength of paper sheets treated with MAAC or chitosan solutions and cured at 90 and 170 °C was investigated. Escherichia coli was used to evaluate the antibacterial performance of the treated paper sheets. The antibacterial performance was determined by measuring the absorbance at 610 nm based on the turbidity of the bacterial suspension on the surface of...

  3. Synthesis and characterization of maleic anhydride esterified corn starch by the dry method.

    Science.gov (United States)

    Zuo, Yingfeng; Gu, Jiyou; Yang, Long; Qiao, Zhibang; Tan, Haiyan; Zhang, Yanhua

    2013-11-01

    Maleic anhydride esterified starch was synthesized by a dry method using corn starch as the material and maleic anhydride as the esterifying agent. The esterified starch (ES) was analyzed by Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS), which confirmed that there was a successful esterification reaction between the maleic anhydride and corn starch. The effects of reaction temperature and time on the degree of substitution of esterified starch were studied, where the results showed that 80 °C of reaction temperature and 3h of reaction time were optimal conditions. The result of XPS testing demonstrated that the esterification reaction led to increase of ester bonds in starch. The scanning electron microscopy (SEM) and laser particle size analyzer results showed that esterification led to roughness on the surface of the starch particle, and the particle size and distribution rate of esterification starch became larger. X-ray diffraction (XRD) analysis demonstrated that esterification reaction did not change the crystalline type of native starch. The differential scanning calorimeter (DSC) and thermo gravimetric analysis (TGA) confirmed that destruction of the crystal structure resulted in improved thermoplasticity of the starch, decreased the gelatinization temperature and increased the thermogravimetric rate of esterification starch. Copyright © 2013 Elsevier B.V. All rights reserved.

  4. Influence of the degree of hydrolysis of poly(styrene-alt-maleic anhydride) on miscibility with poly(vinyl acetate)

    NARCIS (Netherlands)

    Bosma, M.; Vorenkamp, E.J.; Brinke, G. ten; Challa, G.

    1988-01-01

    The influence of the hydrolysis of anhydride groups in poly(styrene-alt-maleic anhydride) (PSMA) on its miscibility with poly(vinyl acetate) (PVAc) is investigated. The cloudpoint curves of these blends are determined as a function of the degree of hydrolysis. The miscibility is shown to improve wit

  5. Development of novel melt-compounded starch-grafted polypropylene/polypropylene-grafted maleic anhydride/organoclay ternary hybrids

    Directory of Open Access Journals (Sweden)

    E. Lafranche

    2012-11-01

    Full Text Available Starch-grafted polypropylene (PP-g-starch/organoclay nanocomposites were melt-compounded using a corotating twin-screw extruder. Homopolymer or copolymer-based polypropylene-grafted maleic anhydrides (PP-g-MA with different molecular weights and different maleic anhydride (MA grafting levels were added at different weight contents as compatibilizer. Two organo-modified montmorillonites were used, the first one containing polar functional groups (Cloisite®30B having affinity to the starch phase, and the other one containing non polar-groups (Cloisite®20A having affinity to the polypropylene phase of the polymer matrix. Whatever the MA grafting level and the molecular weight and content of PP-g-MA, no significant immiscibility of PP-g-starch/PP-g-MA blends is evidenced. Regarding clay dispersion, adding a low content of ethylene-propylene copolymer-based PP-g-MA compatibilizer having a high MA-grafting level, and a polar organoclay (Cloisite®30B is the most desirable formulation to optimize clay intercalation and exfoliation in PP-g-starch. Nevertheless, regarding the reinforcement effect, whatever the PP-g-MA compatibilizer, the addition of non polar organoclay (Cloisite®20A is preferably recommended to reach higher tensile properties (modulus, yield stress, strength without significant loss of ductility.

  6. Solid-Liquid Equilibria of Several Binary and Ternary Systems Containing Maleic Anhydride%顺丁烯二酸酐在单一溶剂和混合溶剂中的固液平衡研究

    Institute of Scientific and Technical Information of China (English)

    马沛生; 陈明鸣; 董奕

    2002-01-01

    Solid-liquid equilibria (SLE) of three binary systems and seven ternary systems containing maleic anhydride(MA) are measured by visual method. The experimental data are compared with the calculated ones with modified universal quasichemical functional group activity coefficient(UNIFAC) method in which the interaction parameters between groups come from two sources, dortmund data bank(DDB), if there's any, and correlations based on our former presented experimental SLE data of twenty binary systems. New groups of MA, ACCOO group, COO group, >C=O group and cy-CH2 group are defined and the SLE data of maleic anhydride in isopropyl acetate in literature are cited in order to assess the new interaction parameters, correlated with Wilson equation and the λh equation. The modified UNIFAC method with these new regressed interaction parameters is also used to predict other three binary systems containing maleic anhydride.

  7. Plasma Polymerized Thin Films of Maleic Anhydride and 1,2-methylenedioxybenzene for Improving Adhesion to Carbon Surfaces

    DEFF Research Database (Denmark)

    Drews, Joanna Maria; Goutianos, Stergios; Kingshott, Peter

    2007-01-01

    Low power 2-phase AC plasma polymerization has been used to surface modify glassy carbon substrates that are used as an experimental model for carbon fibers in reinforced composites. In order to probe the role of carboxylic acid density on the interfacial adhesion strength a combination...... of different plasma powers and monomer compositions was used. Maleic anhydride (MAR) and 1,2-methylenedioxybenzene (MDOB) were plasma deposited separately and as mixtures to create layers with different surface compositions. In all cases the MAR was hydrolyzed to form carboxylic acid groups. Some carboxylic...... total veflectanc~ Fourier transform infrared spectroscopy. Atomic force microscopy was used to measure the thickness of the plasma films and to monitor the surface roughness for the different polymerization conditions. Finally, preliminary results of fracture energy measurements of the plasma modified...

  8. SYNTHESIS OF MESOPOROUS POLY(STYRENE-co-MALEIC ANHYDRIDE)/SILICA HYBRID MATERIALS VIA A NONSURFACTANT-TEMPLATED SOL-GEL PROCESS

    Institute of Scientific and Technical Information of China (English)

    Jie-bin Pang; Kun-yuan Qiu; Yen Wei

    2000-01-01

    Mesoporous poly(styrene-co-maleic anhydride)/silica hybrid materials have been prepared. The synthesis was achieved by the HCl-catalyzed sol-gel reactions of tetraethyl orthosilicate (TEOS) and styrene-maleic anhydride copolymer in the presence of 3-aminopropyl triethoxysilane (APTES) as a coupling agent and citric acid as a nonsurfactant template or pore-forming agent, followed by ethanol extraction. Characterization results from nitrogen sorption isotherms and powder Xray diffraction indicate that polymer-modified mesoporous materials with large specific surface areas (e.g. 900 m2/g) and pore volumes (e.g. 0.6 cm3/g) could be prepared. As the citric acid concentration is increased, the specific surface areas, pore volumes and pore diameters of the hybrid materials increase.

  9. Maleic anhydride-g-low density polyethylene: Modification of LDPE molecular structure by γ-irradiation

    Science.gov (United States)

    Sheeja, Manaf, O.; Sujith, A.

    2017-06-01

    Polymer modification by radiation grafting of monomers onto polymers has received much attention recently. In the current study, γ-irradiation technique was used to achieve graft copolymerization of maleic anhydride (MA) onto low-density polyethylene (LDPE). To optimize, the process was performed at different γ-irradiation doses and MA concentration. The microstructure of grafted polymer film has been characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry, field emission-scanning electron microscopy, and atomic force microscopy. The studies performed made possible the selection of experimental protocols adequate for the production of new copolymeric materials with high grafting yield.

  10. Space charge behaviour in maleic anhydride grafted polyethylene/ethylene - vinyl - acetate copolymer laminates

    Science.gov (United States)

    Lee, Seung Hyung; Park, Jung Ki; Han, Jae Hong; Suh, Kwang S.

    1997-01-01

    Charge distributions in maleic anhydride (MAH) grafted polyethylene (g-PE)/ethylene - vinyl - acetate (EVA) copolymer laminates have been measured with materials of different composition. All laminates showed interfacial charge, the polarity and the magnitude of which are explained by interfacial polarization. It was found that the interfacial charge increased with the increase of MAH content in the g-PE, whereas it decreased with the increase of vinyl - acetate content in the EVA. This feature was attributed to the differences in electrical conductivity of the materials. Details of the experimental results are described.

  11. Preparation and Crystallization of Carbon Nanotube/maleic Anhydride-grafted Polypropylene Composites

    Institute of Scientific and Technical Information of China (English)

    Xiaohua CHEN; Jing HU; Lingping ZHOU; Wenhua LI; Zi YANG; Yanguo WANG

    2008-01-01

    Carbon nanotube (CNT)/maleic acid anhydride (MAH)-grafted polypropylene (PP) composites were prepared by in situ grafting method. Infrared spectroscopy showed that the CNTs were linked to PP by MAH grafting. The microstructures and calorimetry analysis indicated that the crystallization behaviors of the filled and unfilled PP were quite different. The addition of CNTs dramatically reduced the spherulite size, increased crystallization rate and improved the thermal stability of PP. These results confirmed the expected nucleant effect of CNT on the crystallization of PP. Scanning and transmission electron microscopy showed that the CNTs were dispersed homogeneously, indicating that the original CNT bundles were separated into individual tubes by the grafting.

  12. Langmuir and Langmuir-Blodgett films of a maleic anhydride derivative: effect of subphase divalent cations.

    Science.gov (United States)

    Martín-García, B; Velázquez, M Mercedes; Pérez-Hernández, J A; Hernández-Toro, J

    2010-09-21

    We report the study of the equilibrium and dynamic properties of Langmuir monolayers of poly(styrene-co-maleic anhydride) partial 2-buthoxyethyl ester cumene terminated polymer and the effect of the Mg(NO(3))(2) addition in the water subphase on the film properties. Results show that the polymer monolayer becomes more expanded when the electrolyte concentration in the subphase increases. Dense polymer films aggregate at the interface. The aggregates are transferred onto silicon wafers using the Langmuir-Blodgett methodology and the morphology is observed by AFM. The structure of aggregates depends on the subphase composition of the Langmuir film transferred onto the silicon wafer.

  13. Graft Copolymers of Maleic Anhydride and Its Isostructural Analogues: High Performance Engineering Materials

    CERN Document Server

    Rzayev, Zakir M O

    2011-01-01

    This review summarizes the main advances published over the last 15 years outlining the different methods of grafting, including reactive extruder systems, surface modification, grafting and graft copolymerization of synthetic and natural polymers with maleic anhydride and its isostructural analogues such as maleimides and maleates, and anhydrides, esters and imides of citraconic and itaconic acids, derivatives of fumaric acid, etc. Special attention is spared to the grafting of conventional and non-conventional synthetic and natural polymers, including biodegradable polymers, mechanism of grafting and graft copolymerization, in situ grafting reactions in melt by reactive extrusion systems, in solutions and solid state (photo- and plasma-induced graftings), and H-bonding effect in the reactive blend processing. The structural phenomena, unique properties and application areas of these copolymers and their various modifications and composites as high performance engineering materials have been also described.

  14. CHARGE-TRANSFER AND ENERGY-TRANSFER IN THE PHOTO-INDUCED COPOLYMERIZATION OF 2-VINYLNAPHTHALENE WITH MALEIC ANHYDRIDE

    Institute of Scientific and Technical Information of China (English)

    LI Tong; LUO Bin; LI Shanjun; CHU Guobei

    1990-01-01

    The initiation mechanism of the copolymerization of 2-vinylnaphthalene with maleic anhydride was studied under irradiation of 365 nm. The excited complex was formed from ( 1 ) the local excitation of 2-vinylnaphthalene followed by the charge-transfer interaction with maleic anhydride and ( 2 ) the excitation of the ground state charge-transfer complex, and then it collapsed to 1,4-tetramethylene biradical for initiation. A 1:1 alternating copolymer was formed in different monomer feeds. Addition of benzophenone could greatly enhance the rate of copolymerization through energy-transfer mechanism.

  15. Flexible Polyimide Aerogel Cross-linked by Poly(maleic Anhydride-alt-alkylene)

    Science.gov (United States)

    Guo, Haiquan; Meador, Mary Ann B.; Wilkewitz, Brittany Marie

    2014-01-01

    Aerogels are potential materials for aerospace applications due to their lower thermal conductivity, lighter weight, and low dielectric constant. However, silica aerogels are restricted due to their inherent fragility, hygroscopic nature, and poor mechanical properties, especially in extreme aerospace environments. In order to fit the needs of aerospace applications, developing new thermal insulation materials that are flexible, and moisture resistant is needed. To this end, we fabricated a series of polyimide aerogels crosslinked with different poly(maleic anhydride-alt-alkylene)s as seen in Scheme 1. The polyimide oligomers were made with 3,3,4,4-biphenyltetracarboxylic dianhydride (BPDA), and different diamines or diamine combinations. The resulting aerogels have low density (0.06 gcm3 to 0.16 gcm3) and high surface area (240-440 m2g). The effect of the different backbone structures on density, shrinkage, porosity, surface area, mechanical properties, moisture resistance and thermal properties will be discussed. These novel polyalkylene-imide aerogels may be potential candidates for applications such as space suit insulation for planetary surface missions, insulation for inflatable structures for habitats, inflatable aerodynamic decelerators for entry, descent and landing (EDL) operations, and cryotank insulation for advance space propulsion systems. Scheme 1. Network of polyimide aerogels crosslinked with deifferent poly(maleic anhydride).

  16. EFFECT OF MALEIC ANHYDRIDE ON KENAF DUST FILLED POLYCAPROLACTONE/THERMOPLASTIC SAGO STARCH COMPOSITES

    Directory of Open Access Journals (Sweden)

    Siang Yee Chang,

    2012-02-01

    Full Text Available The utilization of biodegradable polymers for various applications has been restricted mainly by its high cost. This report aims to study the water absorption and mechanical properties of kenaf dust-filled polycaprolactone/thermoplastic sago starch biodegradable composites as a function of filler loading and treatment with maleic anhydride. While water absorption in untreated biocomposites increased as a function of filler loading, treated biocomposites resulted in weight loss, whereby low molecular weight substances were dissolved into the aging medium. The kenaf dust imparts reinforcing effects on the biocomposites, resulting in improved mechanical properties. This is further attested by morphological studies in which kenaf dust was well dispersed in the polycaprolactone/ thermoplastic sago starch blend matrix. The addition of maleic anhydride into the polycaprolactone/thermoplastic sago starch blend resulted in a homogeneous mixture. At low filler loading, strain at break of the maleated polycaprolactone/thermoplastic sago starch blend increased at the expense of tensile strength and modulus. This is most likely due to the excessive dicumyl peroxide content, which caused chain scission of the polycaprolactone backbone. Tensile strength and modulus improved only when high filler loading was employed.

  17. Synthesis and properties of starch-g-poly(maleic anhydride-co-vinyl acetate

    Directory of Open Access Journals (Sweden)

    2010-01-01

    Full Text Available Starch-g-poly(maleic anhydride-co-vinyl acetate (SMV was synthesized via the esterification reaction of starch with the copolymer of maleic anhydride and vinyl acetate. The carboxylic unit percentage (CUP of SMV was tailored with reaction conditions, and it ranged from 29.8 to 46.9%. The structure and the morphology of the copolymers were characterized with Fourier Transform Infrared spectroscopy and X-ray diffraction analysis. It was found that SMV could form complex with some metal cations such as Ca2+, Pb2+ and Hg2+ or cationic polyelectrolyte chitosan, and precipitate from the solution. The weight of precipitation increases with an increase of the CUP of SMV. In addition, a physically cross-linked hydrogel of SMV/poly(vinyl alcohol (PVA was obtained by freeze/thaw technique. Scanning electron microscopy exhibited the hydrogel was uniform. The gel exhibited pH-responsive re-swelling. The maximum swelling-ratio values of SMV/PVA (9:1, wt/wt gel were 3.29 and 5.34 in HCl (pH 1.0 and phosphate-buffer saline (PBS (pH 12 respectively.

  18. Effect of Solvent and Acid-Base on Palladium(ll)-catalyzed Dicarbonylation of Terminal Acetylenes: a General, Efficient andStereoselective Synthesis of Maleic Diesters and Maleic Anhydrides

    Institute of Scientific and Technical Information of China (English)

    JIANG, Huan-Feng; LI, JiN-Heng; CHEN, Ming-Cai

    2001-01-01

    The productions of maleic diesters and maleic anhydrises depend on the effect of solvint and acid-bade of solvent and acid-base in palladium-catalyzed dicarbonylation of terminal acetylenes. For primaryand secondary alcohol in benzene.only maleic diesters wereobtained stereospecifically from the sicabonylation ofacetylenes in the presence of PdCl2,and NaHCO3.For tERTIARy alcohols,maleic anhydrides were synthesized selectively.

  19. Oil recovery with sulfomethylated poly (lower alkyl vinyl ether/maleic anhydride)

    Energy Technology Data Exchange (ETDEWEB)

    Norton, C.J.; Falk, D.O.

    1973-05-22

    Lower alkyl vinyl ether e.g., methyl vinyl ether, propyl vinyl ether, isopropyl vinyl ether, hexyl vinyl ether, is copolymerized conventionally with maleic anhydride, the resulting copolymer is treated with ammonia or ammonium hydroxide to form the partial amide-ammonium salt, and this salt is in turn treated with formaldehyde and thereafter or simultaneously with ammonium or alkali metal salt sulfite (including bisulfites, etc.) to form an at least partially sulfomethylated copolymer. Aqueous solutions of the sulfomethylated copolymer are useful in increasing the viscosity of drive fluids used in the supplemented recovery of petroleum from subterranean formations. In general, enhancing the polyionic character of mobility control agents used in supplemented recovery of petroleum provides enhanced recovery. Achieving this enhancement of polyionic character through use of sulfonate groups provides a mobility control agent with good ability to sustain viscosity in the presence of brine and lime, usually present in the connate waters of petroleum-bearing formations. (7 claims)

  20. Role of Cellulose Nanocrystals on the Microstructure of Maleic Anhydride Plasma Polymer Thin Films.

    Science.gov (United States)

    Brioude, Michel M; Roucoules, Vincent; Haidara, Hamidou; Vonna, Laurent; Laborie, Marie-Pierre

    2015-07-01

    Recently, it was shown that the microstructure of a maleic anhydride plasma polymer (MAPP) could be tailored ab initio by adjusting the plasma process parameters. In this work, we aim to investigate the ability of cellulose nanocrystals (CNCs) to induce topographical structuration. Thus, a new approach was designed based on the deposition of MAPP on CNCs model surfaces. The nanocellulosic surfaces were produced by spin-coating the CNC suspension on a silicon wafer substrate and on a hydrophobic silicon wafer substrate patterned with circular hydrophilic microsized domains (diameter of 86.9 ± 4.9 μm), resulting in different degrees of CNC aggregation. By depositing the MAPP over these surfaces, it was possible to observe that the surface fraction of nanostructures increased from 20% to 35%. This observation suggests that CNCs can act as nucleation points resulting in more structures, although a critical density of the CNCs is required.

  1. Functionalization of poly(dimethylsiloxane) surfaces with maleic anhydride copolymer films.

    Science.gov (United States)

    Cordeiro, Ana L; Zschoche, Stefan; Janke, Andreas; Nitschke, Mirko; Werner, Carsten

    2009-02-01

    Combining advantageous bulk properties of polymeric materials with surface-selective chemical conversions is required in numerous advanced technologies. For that aim, we investigate strategies to graft maleic anhydride (MA) copolymer films onto poly(dimethylsiloxane) (PDMS) precoatings. Amino groups allowing the covalent attachment of the MA copolymer films to the PDMS (Sylgard 184) surface were introduced either by low-pressure ammonia plasma treatment, or by attachment of 3-aminopropyltriethoxysilane (APTES) onto air plasma-treated PDMS. The resultant coatings were extensively characterized by X-ray photoelectron spectroscopy (XPS), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), contact angle measurements, and atomic force microscopy (AFM). The results show that the impact of the plasma treatment on the physical properties on the topmost surface of the PDMS is critically important for the characteristics of the layered coatings.

  2. Physico-mechanical properties of silanized-montmorillonite reinforced chitosan-co-poly(maleic anhydride) composites

    Science.gov (United States)

    Saputra, O. A.; Fajrin, A.; Nauqinida, M.; Suryanti, V.; Pramono, E.

    2017-07-01

    To solve the problems of dependence on petroleum as starting material in the manufacturing of plastics in Indonesia, green plastic from biopolymer like chitosan to be one of promising options and alternative to replace the conventional plastics. However, to overcome the mechanical and physical properties of chitosan, the addition of reinforcement agent was introduced. In this study, silanized-montmorillonite (sMMt) has been prepared as a reinforcement agent in the chitosan-co-poly(maleic anhydride) (referred as Cs-MAH) matrix. Silanizing of montmorillonite is one of strategy to improve the interaction between montmorillonite and chitosan, consequently, the mechanical properties, tensile strength of composites contained 6 phr of sMMt improved 56.5% to chitosan. Moreover, the presence both MAH and sMMt on the comosites also reduced swelling degree and swelling area by 20.6% and 26.7%.

  3. Terpolymerization of 2-ethoxy ethylmethacrylate, styrene and maleic anhydride: determination of the reactivity ratios

    Indian Academy of Sciences (India)

    C S Sanmathi; S Prasannakumar; B S Sherigara

    2004-06-01

    Terpolymerization of 2-ethoxyethyl methacrylate (2-EOEMA), styrene (St) and maleic anhydride (Ma) initiated by benzoyl peroxide was carried out in acetone as common solvent for three monomers. The structure and composition of terpolymer were determined by FTIR spectroscopy by recording analytical absorption bands for St (3002 cm-1), Ma (1781 cm-1) and 2-EOEMA (1261 cm-1) units, respectively. The reactivity ratios for the monomers were calculated according to the general copolymerization equations following the Finnemann–Ross and Kelen–Tudos models. The results show that terpolymerization were carried out through primary ``complex" mechanism at near-binary copolymerization of [St...Ma] complex with 2-EOEMA. Structure of the resulting terpolymer illustrated by 1H-NMR and differential scanning calorimeter showed reduction in g value.

  4. Controlled delivery of paclitaxel from stent coatings using novel styrene maleic anhydride copolymer formulations.

    Science.gov (United States)

    Richard, Robert; Schwarz, Marlene; Chan, Ken; Teigen, Nikolai; Boden, Mark

    2009-08-01

    The controlled release of paclitaxel (PTx) from stent coatings comprising an elastomeric polymer blended with a styrene maleic anhydride (SMA) copolymer is described. The coated stents were characterized for morphology by scanning electron microscopy (SEM) and atomic force microscopy (AFM), and for drug release using high-performance liquid chromatography (HPLC). Differential scanning calorimetry (DSC) was used to measure the extent of interaction between the PTx and polymers in the formulation. Coronary stents were coated with blends of poly(b-styrene-b-isobutylene-b-styrene) (SIBS) and SMA containing 7% or 14% maleic anhydride (MA) by weight. SEM examination of the stents showed that the coating did not crack or delaminate either before or after stent expansion. Examination of the coating surface via AFM after elution of the drug indicated that PTx resides primarily in the SMA phase and provided information about the mechanism of PTx release. The addition of SMA altered the release profile of PTx from the base elastomer coatings. In addition, the presence of the SMA enabled tunable release of PTx from the elastomeric stent coatings, while preserving mechanical properties. Thermal analysis reveled no shift in the glass transition temperatures for any of the polymers at all drug loadings studied, indicating that the PTx is not miscible with any component of the polymer blend. An in vivo evaluation indicated that biocompatibility and vascular response results for SMA/SIBS-coated stents (without PTx) are similar to results for SIBS-only-coated and bare stainless steel control stents when implanted in the non-injured coronary arteries of common swine for 30 and 90 days.

  5. Fluorescence and Judd-Ofelt analysis of rare earth complexes with maleic anhydride and acrylic acid

    Institute of Scientific and Technical Information of China (English)

    WEN Shipeng; ZHANG Xiaoping; HU Shui; ZHANG Liqun; LIU Li

    2008-01-01

    Two kinds of Eu-complexes, Eu(TTA)2(Phen)(AA) and Eu(TTA)2(Phen)(MA) (HTFA=2-Thenoyltrifluoroacetone, Phen=1,10-phenanthroline, AA=acrylic acid, MA=Maleic anhydride), which combined the excellent fluorescence properties of Eu(TTA)2(Phen)(H2O) and the reactivity of acrylic acid and maleic anhydride with radicals, were synthesized. The two complexes were characterized by elemental analysis, infrared (IR) spectra, and X-ray photoelectron spectroscopy (XPS). Based on the data shown from the fluorescent spectra of the Eu-MA and Eu-AA complexes, the Ωλ (λ=2 and 4) experimental intensity parameters were calculated. The results demonstrated that the Ω2 intensity parameters for the two complexes were smaller than those for the Eu(TTA)2(Phen)(H2O) complex, indicating that a less symmetri-cal chemical environment existed in the complexes. It implied that the radiative efficiency of the 5D0 of these two complexes could be en-hanced by ligand of MA and AA, respectively. The luminescent lifetime of the Eu-AA (τ=7.26×10-4 s) or Eu-MA complex (τ=-8.12×10-4 s) was higher than that of the Eu(TTA)2(Phen)(H2O) complex, which was attributed to the substitution of the water molecule (H2O) in Eu(TTA)2(Phen)(H2O) by the MA or AA ligand.

  6. Effect of maleic anhydride treatment on the mechanical properties of sansevieria fiber/vinyl ester composites

    Science.gov (United States)

    Pradipta, Rangga; Mardiyati, Steven, Purnomo, Ikhsan

    2017-03-01

    Sanseviera trifasciata commonly called mother-in-law tongue also known as snake plant is native to Indonesia, India and Africa. Sansevieria is a new fiber in composite research and has showed promising properties as reinforcement material in polymer matrix composites. Chemical treatment on reinforcing fiber is crucial to reduce hydrophilic tendency and thus improve compatibility with the matrix. In this study, effect of maleic anhydride as chemical treatment on the mechanical properties of Sansevieria fiber/vinyl ester composite was investigated. Sansevieria fibers were immersed by using NaOH 3% for two hours at 100°C and then treated by using maleic anhydrate for two hours at 120°C. Composites were prepared by solution casting with various volume fractions of fiber; 0%, 2.5%, 5%, 7.5% and 10%. Actual density, volume fraction of void and mechanical properties of composite were conducted according to ASTM standard testing methods D792, D3171 and D3039. It was found that mechanical properties of composites increased as volume fractions of fiber was increased. The highest tensile strength and modulus of elasticity of composites were 57.45 MPa and 3.47 GPa respectively, obtained from composites with volume fraction of fiber 10%.

  7. Non-woven fibrous materials with antibacterial properties prepared by tailored attachment of quaternized chitosan to electrospun mats from maleic anhydride copolymer.

    Science.gov (United States)

    Ignatova, Milena; Petkova, Zhanina; Manolova, Nevena; Markova, Nadya; Rashkov, Iliya

    2012-01-01

    In order to impart antibacterial properties to microfibrous electrospun materials from styrene/maleic anhydride copolymers, quaternized chitosan derivatives (QCh) containing alkyl substituents of different chain lengths are covalently attached to the mats. A complete inhibition of the growth of bacteria, S. aureus (Gram-positive) and E. coli (Gram-negative), for a contact time of 30–120 min or a decrease of the bacterial titer by 2–3 log units is observed depending on the quaternization degree, the chain length of the alkyl substituent, and the molar mass of QCh. The modified mats are also effective in suppressing the adhesion of pathogenic S. aureus bacteria.

  8. Effect of maleic anhydride-aniline derivative buffer layer on the properties of flexible substrate heterostructures: Indium tin oxide/nucleic acid base/metal

    Energy Technology Data Exchange (ETDEWEB)

    Stanculescu, A., E-mail: sanca@infim.ro [National Institute of Materials Physics, 105 bis Atomistilor Street, P.O. Box MG-7, 077125, Bucharest-Magurele (Romania); Socol, M. [National Institute of Materials Physics, 105 bis Atomistilor Street, P.O. Box MG-7, 077125, Bucharest-Magurele (Romania); Socol, G.; Mihailescu, I.N. [National Institute for Laser, Plasma and Radiation Physics, P.O. Box MG-36, 077125, Bucharest-Magurele (Romania); Girtan, M. [Laboratoire de Photonique d' Angers, Universite d' Angers, 2, Bd. Lavoisier, 49045, Angers (France); Preda, N. [National Institute of Materials Physics, 105 bis Atomistilor Street, P.O. Box MG-7, 077125, Bucharest-Magurele (Romania); Albu, A.-M. [Department of Polymer Science, University ' Politehnica' of Bucharest, Bucharest (Romania); Stanculescu, F. [University of Bucharest, Faculty of Physics, Str. Atomistilor nr.405, P.O. Box MG-11, Bucharest-Magurele, 077125 (Romania)

    2011-12-01

    This paper presents some investigations on the properties of guanine (G) and cytosine (C) based heterostructures deposited on flexible substrates. The effects of two types of maleic anhydride-aniline derivatives (maleic anhydride-cyano aniline or maleic anhydride-2,4 dinitroaniline) buffer layer, deposited between indium tin oxide and (G) or (C) layer, on the optical and electrical properties of the heterostructures have been identified. The heterostructures containing a film of maleic anhydride-2,4 dinitroaniline have shown a good transparency and low photoluminescence in visible range. This buffer layer has determined an increase in the conductance only in the heterostructures based on (G) and (C) deposited on biaxially-oriented polyethylene terephthalate substrate.

  9. SELECTIVE HYDROGENATION OF MALEIC ANHYDRIDE TO Y-BUTYROLACTONE OVER PD/AL(2)O(3) CATALYST USING SUPERCRITICAL CO(2) AS SOLVENT

    Science.gov (United States)

    A selective hydrogenation of maleic anhydride to either y-butyrolactone or succinic anhydride over simple Pd/Al(2)O(3) catalyst under supercritical CO(2) medium is described for the first time which has considerable promise for obht lab-scale as well as industrial selective hydro...

  10. Morphology and Mechanical Properties of Nylon 6/PBT Blends Compatibilized with Styrene/Maleic Anhydride Copolymer

    Institute of Scientific and Technical Information of China (English)

    QIN Shu-hao; YU Jie; ZHENG Qiang; HE Min; ZHU Hong

    2007-01-01

    The mechanical properties and dynamic mechanical properties of blends composed of Nylon 6 and poly( butylenes terephthalate) (PBT), with styrene/maleic anhydride(SMA) as compatibilizer, were studied. The observation on the morphologies of the etched surfaces of the cryogenically fractured specimens via scanning electron microscopy(SEM)demonstrated that in the compatibilized Nylon 6/PBT blends, there exists a finer and more uniform dispersion induced by thein-situ interfacial chemical reactions during the preparation than that in the corresponding uncompatibilized blends. On the other hand, the overall mechanical properties of the compatibilized blends could be remarkably improved compared with those of the uncompatibilized ones. Moreover, increasing the amount of the compatibilizer SMA leads to a more efficient dispersion of the PBT phase in Nylon 6/PBT blends. Furthermore, there exists an optimum level of SMA added to achieve the maximum mechanical properties. As far as the mechanism of this reactive compatibilization is concerned, the enhanced interfacial adhesion is necessary to obtain improved dispersion, stable phase morphology, and better mechanical properties.

  11. Separation of maleic anhydride grafted polypropylene using multidimensional high-temperature liquid chromatography.

    Science.gov (United States)

    Prabhu, K N; Macko, T; Brüll, R; Remerie, K; Tacx, J; Garg, P; Ginzburg, A

    2016-04-01

    Functionalization addresses a property gap of polyolefins and opens new perspectives due to improved surface properties in applications like composites (e.g., glass fiber reinforced polypropylene) and anti-corrosive coatings for metals. Various techniques have been developed to characterize functionalized polyolefins, yet no analytical approach addressing their chemical heterogeneity exists. Using High Temperature Size Exclusion Chromatography (HT-SEC) coupled to infrared spectroscopy we could show for two model samples of polypropylene grafted maleic anhydride (PP-g-MA), differing in their nominal MA content, that the grafting density increases with decreasing molar mass. Crystallization Analysis Fractionation (CRYSTAF) does not enable to separate these samples according to their composition to the extent required. Yet, when using High Temperature High Performance Liquid Chromatography (HT-HPLC), with either silica gel or Mica as stationary phase and a gradient mobile phase, a deformulation into a grafted and a non-grafted fraction could be achieved. This was confirmed by analyzing the eluted fractions by infrared spectroscopy. Hyphenating the separation according to composition with a separation according to molar mass (HT-HPLC x HT-SEC) enabled for the first time to reveal the bivariate distribution of PP-g-MA with regard to the molar mass and composition. Using on-line infrared detection quantitative information on the compositional and molar mass parameters of the individual fractions could be obtained.

  12. THERMAL properties and morphology of Polypropylene/Polycarbonate/Polypropylene-Graft-Maleic anhydride blends

    Directory of Open Access Journals (Sweden)

    Mat-Shayuti M. S.

    2016-01-01

    Full Text Available This work investigates the effect of blending polycarbonate (PC into polypropylene (PP matrix polymer on thermal properties and morphology. The blends, containing 5% to 35% of polycarbonate and 5% compatibilizer, were compounded using twin-screw extruder and fabricated into standard tests samples using injection or compression molding. The compatibilizer used was polypropylene-graft-maleic anhydride (PP-g-MA. Thermogravimetric analysis (TGA showed improved thermal degradation temperature of PP/PC/PP-g-MA blends compared to pure PP. As PC content increased, the thermal degradation temperature also improved. The highest improvement of thermal degradation temperature was 23.3%, demonstrated by 60/35/5 composition. It was found that the thermal stability of PP/PC blends was improved with the addition of PP-g-MA. PP-g-MA was suspected to enhance the phase adhesion between PP and PC, thus improving thermal stability. Microscopy analysis showed PC reinforcement phase existed as particulates dispersed in PP matrix phase. PC also was in irregular shapes of fibers or flakes in certain compositions, depending on PC fraction and compatibilizer content.

  13. A New Process for Maleic Anhydride Synthesis from a Renewable Building Block: The Gas-Phase Oxidehydration of Bio-1-butanol.

    Science.gov (United States)

    Pavarelli, Giulia; Velasquez Ochoa, Juliana; Caldarelli, Aurora; Puzzo, Francesco; Cavani, Fabrizio; Dubois, Jean-Luc

    2015-07-01

    We investigated the synthesis of maleic anhydride by oxidehydration of a bio-alcohol, 1-butanol, as a possible alternative to the classical process of n-butane oxidation. A vanadyl pyrophosphate catalyst was used to explore the one-pot reaction, which involved two sequential steps: 1) 1-butanol dehydration to 1-butene, catalysed by acid sites, and 2) the oxidation of butenes to maleic anhydride, catalysed by redox sites. A non-negligible amount of phthalic anhydride was also formed. The effect of different experimental parameters was investigated with chemically sourced 1-butanol, and the results were then confirmed by using genuinely bio-sourced 1-butanol. In the case of bio-1-butanol, however, the purity of the product remarkably affected the yield of maleic anhydride. It was found that the reaction mechanism includes the oxidation of butenes to crotonaldehyde and the oxidation of the latter to either furan or maleic acid, both of which are transformed to produce maleic anhydride.

  14. SYNTHESIS AND CHARACTERIZATION OF A NEW COMBLIKE POLYMER BASED ON POLY (VINYL METHYL ETHER-ALT-MALEIC ANHYDRIDE) BACKBONE

    Institute of Scientific and Technical Information of China (English)

    DING Liming; LIN Yunqing; ZHOU Zinan; NI Jianlong; CHEN Donglin

    1995-01-01

    A new comblike polymer host for polymer electrolyte was synthesized by reacting monomethyl ether of poly(ethylene glycol) with poly(vinyl methyl ether-alt-maleic anhydride) and endcapping the residual carboxylic acid with methanol. Butanone was selected as a solvent for the esterification in order to obtain a completely soluble product. The synthesis process was traced through by IR. Compared with the model compounds, the presumed structure of this comblike polymer has been proved to be valid by 13C NMR. The comb polymer is a white rubbery solid. It can be dissolved in butanone and THF, and manifests good film forming ability.

  15. Short-chain grafting of tetrahydrofuran and 1,4-dioxane cycles on vinylchloride-maleic anhydride copolymer

    Directory of Open Access Journals (Sweden)

    2009-01-01

    Full Text Available Mass increase of vinylchloride-maleic anhydride (VC-MA copolymer samples aged in tetrahydrofuran (THF or in 1,4-dioxane results from chemical interaction of VC-MA macromolecules with 1,4-dioxane or THF. Microstructure of the products of such modification was proved by infrared spectroscopy (IR- and nuclear magnetic resonance spectroscopy (13C NMR and 1H NMR. Mechanism of modification has been proposed. The results of microstructure research of VC-MA samples aged in THF and in 1,4-dioxane coincide with already known data on the reactions of opening of these and other oxygen-containing cycles under mild conditions.

  16. SELECTIVE SEPARATION OF WATER—ETHANOL MIXTURE THROUGH COPOLYMERIC MEMBRANES.Ⅱ.ACRYLONITRILE AND MALEIC ANHYDRIDE COPOLYMERIC MEMBRANES

    Institute of Scientific and Technical Information of China (English)

    ZHangFuyao; ZhangYifeng; 等

    1993-01-01

    Acrylonitrile(AN) and maleic anhydride(MA) copolymer has been synthesized by radical polymerization using ammonium persulfate and sodium bisulfite as initiator.The pervaporation properties of the copolymeric membranes prepared have been investigated for the first time. The dependences of pervaporation characteristics on coplymer composition,feed concentration and operating temperature have been studied.In order to improve the separation properties of the copolymeric membranes,the membranes were hydrolyzed with 10 wt% soldium hydroxide or potassium hydroxide aqueous solution.The hydrolyzed membranes containing more than 0.069MA mol fraction showed higher tensile strength and separation properties than the original membranes.

  17. Grafting amino drugs to poly(styrene-alt-maleic anhydride) as a potential method for drug release

    Energy Technology Data Exchange (ETDEWEB)

    Khazaei, Ardeshir; Saednia, Shahnaz; Saien, Javad; Abbasi, Fatemeh, E-mail: Khazaei_1326@yahoo.com, E-mail: ssaednia@gmail.com [Faculty of Chemistry, Bu-Ali Sina University, Hamedan (Iran, Islamic Republic of); Kazem-Rostami, Masoud [Young Researchers Club and Elite, Takestan Branch, Islamic Azad University, Takestan (Iran, Islamic Republic of); Sadeghpour, Mahdieh [Department of Chemistry, Takestan Branch, Islamic Azad University, Takestan (Iran, Islamic Republic of); Borazjani, Maryam Kiani [Faculty of Science, Department of Chemistry, Bushehr Payame Noor University (PNU), Bushehr (Iran, Islamic Republic of)

    2013-07-15

    Drug delivery systems based on polymer-drug conjugates give an improved treatment with lower toxicity or side effects and be used for the treatment of different diseases. Conjugates of biodegradable poly(styrene-alt-maleic anhydride) (PSMA), with a therapeutic agents such as amantadine hydrochloride, amlodipine, gabapentin, zonisamide and mesalamine, were afforded by the formation of the amide bonds of the amino drugs that reacted with the PSMA anhydride groups. The amounts of covalently conjugated drugs were determined by a {sup 1}H NMR spectroscopic method, and the in vitro release rate in buffer solution (pH 1.3) was studied at body temperature 37 Degree-Sign C. In kinetic studies, different dissolution models were examined to obtain drug release data and the collected data were well-fitted to the Korsmeyer-Peppas equation, revealing a dominant Fickian diffusion mechanism for drug release under the in vitro conditions. (author)

  18. Reaction kinetics of piperylene and maleic anhydride%间戊二烯和顺酐反应动力学

    Institute of Scientific and Technical Information of China (English)

    雷昊; 杨阿三; 孙勤; 程榕; 郑燕萍

    2011-01-01

    The reaction of C5 and maleic anhydride to synthesize crude methyltetrahydrophthalic anhydride (MTHPA) is a key step in the production of MTHPA and methylhexahydrophthalic anhydride (MHHPA). The reaction kinetics of piperylene and maleic anhydride under the appropriate solvent was studied. Single-factor multilevel experiment was conducted to show the effects of the initial mole ratio (0.4-1. 1 )of maleic anhydride to piperylene, reaction temperature(1545 t), and solvents (MTHPA, toluene and acetone)on the reaction, and the kinetics data of piperylene and maleic anhydride reaction was determined. Based .on the basic mechanisms of Diels-Alder reaction, a kinetics model was established. By regressing experimental data to a linear fitting based on numerical calculation method, the activation energy and pre-exponential factor were obtained with methyl tetrahydrophthalic anhydride, toluene and acetone as solvents. The results show that the reaction process accords with second-order reaction; different solvents have little influence on activation energy, but have great influences on the pre-exponential factor, in which the activation energy and pre-exponential factor approach the highest values when MTHPA is used as solvent.%C5和顺酐反应合成粗甲基四氢苯酐是生产甲基四氢苯酐及甲基六氢苯酐的关键步骤.为了研究C5中间戊二烯与顺酐反应动力学,选择合适溶剂并设计单因素多水平方案,考察了顺酐与间戊二烯摩尔比(0.4-1.1)、反应温度( 15-45℃)、溶剂(甲基四氢苯酐、甲苯和丙酮)等因素对反应的影响,测定了间戊二烯与顺酐反应的动力学数据.依据Diels-Alder反应的基本原理,建立了动力学模型.利用数值计算方法对实验数据进行线性拟合,分别得到了以甲基四氢苯酐、甲苯和丙酮为溶剂时的活化能和指前因子,结果表明反应符合二级反应.不同溶剂对反应的活化能影响较小,对指前因子影响较大,其中以甲基

  19. Amphiphilic graft copolymer based on poly(styrene-co-maleic anhydride with low molecular weight polyethylenimine for efficient gene delivery

    Directory of Open Access Journals (Sweden)

    Duan XP

    2012-09-01

    Full Text Available Xiaopin Duan,1,2 Jisheng Xiao,2 Qi Yin,2 Zhiwen Zhang,2 Shirui Mao,1 Yaping Li21School of Pharmacy, Shenyang Pharmaceutical University, Shenyang, 2Center of Pharmaceutics, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, ChinaBackground and methods: A new amphiphilic comb-shaped copolymer (SP was synthesized by conjugating poly(styrene-co-maleic anhydride with low molecular weight polyethyleneimine for gene delivery. Fourier transform infrared spectrum, 1H nuclear magnetic resonance, and gel permeation chromatography were used to characterize the graft copolymer.Results: The buffering capability of SP was similar to that of polyethyleneimine within the endosomal pH range. The copolymer could condense DNA effectively to form complexes with a positive charge (13–30 mV and a small particle size (130–200 nm at N/P ratios between 5 and 20, and protect DNA from degradation by DNase I. In addition, SP showed much lower cytotoxicity than polyethyleneimine 25,000. Importantly, the gene transfection activity and cellular uptake of SP-DNA complexes were all markedly higher than that of complexes of polyethyleneimine 25,000 and DNA in MCF-7 and MCF-7/ADR cell lines.Conclusion: This work highlights the promise of SP as a safe and efficient synthetic vector for DNA delivery.Keywords: poly(styrene-co-maleic anhydride, polyethylenimine, DNA, gene delivery

  20. Using maleic anhydride functionalized graphene oxide for improving the interfacial properties of carbon fiber/BMI composites

    Directory of Open Access Journals (Sweden)

    W. Li

    2016-11-01

    Full Text Available Maleic anhydride functionalized graphene oxide (MAH-GO was synthesized and then introduced into carbon fiber (CF reinforced bismaleimide (BMI composites, with the aim of improving the interfacial adhesion strength between CF and BMI resin. Various characterization techniques including Fourier transform infrared spectroscopy (FT-IR, X-ray photoelectron spectra (XPS and thermogravimetric analysis (TGA demonstrated that the maleic anhydride has been successfully grafted onto the GO surfaces. The study showed that the interlaminar shear strength (ILSS and flexural properties of CF/BMI composites were all improved by the incorporation of GO and MAH-GO, and the MAH-GO showed the substantially improved effect due to the strong interaction between the MAH-GO and the resin matrix. The maximum increment of the ILSS, flexural strength and flexural modulus of composites were 24.4, 28.7 and 49.7%, respectively. Scanning electron microscope (SEM photographs of the fracture surfaces revealed that the interfacial bonding between CF and resin matrix was significantly strengthened by the addition of MAH-GO. The results suggest that this feasible method may be an ideal substitute for the traditional method in the interfacial modification of composites.

  1. 马来酸酐改性聚乳酸对成骨细胞黏附、增殖和分化的研究%Effects of Maleic Anhydride-modified Poly(D,L-lactic acid) on the Adhesion,Proliferation and Differentiation of Osteoblasts

    Institute of Scientific and Technical Information of China (English)

    向燕; 王远亮; 罗彦凤; 张兵兵; 辛娟; 郑丹芳

    2011-01-01

    The main objective of this study was to observe the adhesion, proliferation and differentiation of mouse os-teblast-like MC3T3-E1 cells cultured on maleic anhydride-modified poly(D,L-lactic acid) (MPLA) and poly(D,L-lactic acid) (PDLLA) polymers, and to evaluate the cytocompatibility of MPLA polymer. The effects of MPLA and PDLLA polymers on the morphology, adhesion, proliferation, the content of total cellular protein, alkaline phospha-tase (ALP) activity and the content of Ca of MC3T3-E1 cells were explored. These results indicated that MC3T3-E1 cells on MPLA polymer adhered and spread more fully. On MPLA polymer, the proliferation, total protein content, ALP activity, Ca content of the cells were significantly higher than those of the cells on PDLLA polymer (P< 0. 01). It was concluded that MPLA polymer could promote the adhesion, spreading, proliferation and the synthesis of protein of osteoblasts, and also induced the differentiation and mineralization of osteoblasts, suggesting that MPLA polymer might have the better cytocompatibility than PDLLA.%通过研究马来酸酐改性聚乳酸(MPLA)和聚乳酸(PDLLA)材料表面对MC3T3-E1成骨细胞形态、黏附、增殖、细胞总蛋白含量、碱性磷酸酶活性及细胞分泌无机钙含量的影响,评价MPLA和PDLLA材料的细胞相容性.结果显示:与PDLLA相比,MPLA材料上的成骨细胞完全黏附和充分铺展;MPLA材料上细胞的增殖速率、细胞总蛋白含量、细胞碱性磷酸酶活性及细胞分泌的无机钙含量都显著高于PDLLA(P<0.01).这些结果说明,MPLA材料能促进MC3T3-E1成骨细胞的黏附、铺展、增殖及蛋白质的合成,并能促进成骨细胞的分化和矿化,与PDLLA材料相比具有更好的细胞相容性.

  2. Grafting of diethyl maleate and maleic anhydride onto styrene-b-(ethylene-co-1-butene)-b-styrene triblock copolymer (SEBS)

    NARCIS (Netherlands)

    Picchioni, F.; Ghetti, S.; Passaglia, E.; Ruggeri, G.

    2000-01-01

    In this paper a study of the bulk functionalization of styrene-b-(ethylene-co-1-butene)-b-styrene triblock copolymer (SEBS) with diethyl maleate (DEM) or maleic anhydride (MAH) and dicumyl peroxide (DCP) as initiator in a Brabender mixer is described. The determination of the functionalization degre

  3. Characterization of maleic acid/anhydride copolymer films by low-rate dynamic liquid-fluid contact angle measurements using axisymmetric drop shape analysis.

    Science.gov (United States)

    Uhlmann, Petra; Skorupa, Sebastian; Werner, Carsten; Grundke, Karina

    2005-07-05

    Thin films of alternating maleic acid/anhydride copolymers (poly(octadecene-alt-maleic acid/anhydride), POMA; poly(propene-alt-maleic acid/anhydride), PPMA; poly(styrene-alt-maleic acid/anhydride), PSMA) were studied to unravel the influence of the comonomer characteristics in the backbone on the surface-energetic properties of the copolymer films in the dry state and in contact with aqueous solutions. Water contact angle measurements revealed a graduation of the wettability of the dry hydrolyzed and annealed copolymer films that was dependent on the comonomer unit. It ranged from moderately hydrophilic (PPMA, annealed gamma(sv) = 39.9 mJ/m2) to very hydrophobic (POMA, annealed, gamma(sv) = 18.4 mJ/m2) surfaces. Liquid-fluid contact angle measurements using captive air bubbles were performed in different aqueous media (pure water, phosphate-buffered saline, and 10(-)(3) M KCl of two different pH values (pH = 3 and pH = 10) to study the copolymer films in their hydrated states relevant for biointerfacial phenomena. It was found that the graduation of the wettability of the copolymer films in the dry state is overall maintained upon immersion in aqueous solutions. The dependence of the wettability on the pH value of the aqueous medium could be related to the (de)protonation of the carboxylic groups.

  4. LITHIUM ION CONDUCTING POLYMER ELECTROLYTES BASED ON ALTERNATING MALEIC ANHYDRIDE COPOLYMER WITH OLIGO-OXYETHYLENE SIDE CHAINS

    Institute of Scientific and Technical Information of China (English)

    DING Liming

    1996-01-01

    A comb polymer with oligo-oxyethylene side chains of the type -(CH2CH2O)12CH3 was prepared from methyl vinyl ether/maleic anhydride copolymer and poly (ethylene glycol) methyl ether. The polymer can dissolve LiClO4 salt to form homogeneous amorphous polymer electrolyte. The ac ion conduction was measured using the complex impedance method, and conductivities were investigated as functions of temperatures and salt concentration. The complexes were first found to have two classes of glass transition which increase with increasing salt content. The optimum conductivity attained at 25℃ is in the order of 5.50 × 10-6Scm-1. IR spectroscopy was used to study the cation-polymer interaction.

  5. The Electrical Performance of Polyamide 66/Poly(vinylidene fluoride with Vinyl Acetate-Maleic Anhydride Copolymer

    Directory of Open Access Journals (Sweden)

    Rui Li

    2016-01-01

    Full Text Available The electric performance of the PA66/PVDF blends filled with various amount of copolymer synthesized from vinyl acetate-maleic anhydride (VAMA was investigated. PA66/VAMA/PVDF blends show high dielectric constants, low dielectric loss, and excellent breakdown strength, which were important indexes in the actual application of dielectric material. The VAMA copolymer improves the dielectric and piezoelectric performance of the PA66/PVDF blends. Meanwhile, the addition of VAMA obviously decreases the dielectric loss and breakdown strength of the blends. PA66/PVDF blends filled with 3 wt% VAMA exhibited the best electric ability. The stable dielectric constants of the all-polymeric blends can be tuned by adjusting the content of the VAMA. The created all-polymeric blends represent a novel dielectric material that is technologically simple and easy to process forward application for flexible electronics.

  6. Polycarbonate/Polypropylene-Graft-Maleic Anhydride and Nano-Zeolite-Based Nanocomposite Membrane: Mechanical and Gas Separation Performance

    Directory of Open Access Journals (Sweden)

    Kausar A.

    2016-12-01

    Full Text Available In this effort, blend membrane of polycarbonate (PC and polypropylene-graft-maleic anhydride (PPMA was fabricated via phase inversion technique. The nano-zeolite (NZ was employed as nanofiller. Morphology of PC/PPMA/NZ membrane revealed unique inter-connected branched microstructure. Tensile strength and Young’s Modulus of PC/PPMA/NZ 0.1-5 were in the range of 59.9-74.5 MPa and 111.4-155.2 MPa respectively. The nano-zeolite filler was also effective in enhancing the permselectivity αCO2/N2 (23.5 to 38.5 relative to blend membrane (20.3. The permeability PCO2 of PC/PPMA/NZ 5 membrane was found as 106.2 Barrer. Filler loading enhanced gas diffusivity, however filler content did not significantly influence CO2 and N2 solubility.

  7. Grafting of copolymer styrene maleic anhydride on poly(ethylene terephthalate) film by chemical reaction and by plasma method

    Energy Technology Data Exchange (ETDEWEB)

    Bigan, Muriel; Bigot, Julien [Laboratoire de Chimie Organique et Macromoleculaire (UMR 8009), Universite des Sciences et Technologies de Lille, 59655 Villeneuve d' Ascq Cedex (France); Mutel, Brigitte [Laboratoire de Genie des Procedes d' Interactions Fluides reactifs-Materiaux (UPRES-EA 3751), Batiment C5, Universite des Sciences et Technologies de Lille, 59655 Villeneuve d' Ascq Cedex (France)], E-mail: Brigitte.mutel@univ-lille1.fr; Coqueret, Xavier [Laboratoire Reactions Selectives et Applications (UMR-CNRS 6519) Universite de Reims Champagne-Ardennes, B.P. 1039, 51687 Reims Cedex 2 (France)

    2008-02-15

    This work deals with the chemical grafting of a styrene maleic anhydride copolymer on the surface of a previously hydrolyzed polyethylene terephthalate (PET) film 12 {mu}m thick via covalent bond. Two different ways are studied. The first one involves an activation of the hydrolyzed PET by the triethylamine before the grafting step. In the second one, the copolymer reacts with the 4-dimethylaminopyridine in order to form maleinyl pyridinium salt which reacts with alcohol function of the hydrolyzed PET. Characterization and quantification of the grafting are performed by Fourier transform infrared spectroscopy. Factorial experiment designs are used to optimize the process and to estimate experimental parameters effects. The opportunity to associate the chemical process to a cold remote nitrogen plasma one is also examined.

  8. Preparation and Characterization of Extruded Composites Based on Polypropylene and Chitosan Compatibilized with Polypropylene-Graft-Maleic Anhydride

    Directory of Open Access Journals (Sweden)

    Fernando Javier Carrasco-Guigón

    2017-01-01

    Full Text Available The preparation of composites of synthetic and natural polymers represent an interesting option to combine properties; in this manner, polypropylene and chitosan extruded films using a different proportion of components and polypropylene-graft-maleic anhydride (PPgMA as compatibilizer were prepared. The effect of the content of the biopolymer in the polypropylene (PP matrix, the addition of compatibilizer, and the particle size on the properties of the composites was analyzed using characterization by fourier transform-infrared spectroscopy (FT-IR, scanning electron microscopy (SEM, differential scanning calorimetry (DSC, tensile strength, and contact angle, finding that in general, the addition of the compatibilizer and reducing the particle size of the chitosan, favored the physicochemical and morphological properties of the films.

  9. Réaction du polyisobutène chloré sur l'anhydride maléique : mécanisme. Catalyse par l'anhydride dichloromaléique Reaction of Chlorinated Polyisobutene on Maleic Anhydride. Mechanism. Catalysis by Dichloromaleic Anhydride

    Directory of Open Access Journals (Sweden)

    Sillion B.

    2006-11-01

    Full Text Available Dans cet article le mécanisme de la réaction de condensation du polyisobutène chloré sur l'anhydride maléique, qui sert dans la synthèse d'additif pour lubrifiant, est étudié par une cinétique globale et par un travail sur composés modèles. Il est montré que, dans cette réaction, l'anhydride maléique joue un double rôle : de catalyseur de déshydrochloration par une réactivité de type acide de Lewis organique, de réactif comme diénophile. Grâce à ces résultats, il est proposé une catalyse par l'anhydride dichloromaléique, qui permet une amélioration sensible du procédé. This article examines the mechanism of the chlorinated-polyisobutene condensation reaction on maleic anhydride. The overall kinetics and model compounds are investigated for this reaction which is used in the synthesis of lubricant additives. Maleic anhydride is shown to play the dual role of a dehydrochlorination catalyst by having a reactivity of the organic Lewis acid type and of a reactant like dienophile. These results are used to propose a catalysis by dichloromaleic anhydride which appreciably improves the process.

  10. 54 FR 38044: National Emission Standards for Hazardous Air Pollutants; Benzene Emissions From Maleic Anhydride Plants, Ethylbenzene/Styrene Plants, Benzene Storage Vessels, Benzene Equipment Leaks, and Coke By- Product Recovery Plants

    Science.gov (United States)

    Final Rule on National Emission Standards for Hazardous Air Pollutants; Benzene Emissions From Maleic Anhydride Plants, Ethylbenzene/Styrene Plants, Benzene Storage Vessels, Benzene Equipment Leaks, and Coke By-Product Recovery Plants.

  11. Synthesis and Characterization of Styrene- Ethylene-Propylene-Styrene (SEPS Grafted with Maleic Anhydride (MAH for Use as Coupling Agent in Wood Polymer Composite

    Directory of Open Access Journals (Sweden)

    M. Acevedo-Morantes

    2015-10-01

    Full Text Available Styrene-Ethylene-Propylene-Styrene (SEPS block copolymer was grafted with maleic anhydride (MAH by reactive extrusion (SEPS-g-MAH using an organic peroxide as initiator in the grafting. SEPS-g-MAH was synthesized for use as coupling agent in wood polymer composite (WPC. Identification of this compatibilizer was made using Fourier transform infrared spectroscopy (FTIR and the grafting degree was determinate with titration. The characteristic peaks in FTIR analysis indicated the presence of MAH in the copolymer.

  12. Effect of hydrostatic pressure, temperature, and solvent on the rate of the Diels-Alder reaction between 9,10-anthracenedimethanol and maleic anhydride

    Science.gov (United States)

    Kiselev, V. D.; Kornilov, D. A.; Anikin, O. V.; Latypova, L. I.; Konovalov, A. I.

    2017-03-01

    The rate of the reaction between 9,10-anthracenedimethanol and maleic anhydride in 1,4-dioxane, acetonitrile, trichloromethane, and toluene is studied at 25, 35, 45°C in the pressure range of 1-1772 bar. The rate constants, enthalpies, entropies and activation volumes are determined. It is shown that the rate of reaction with 9,10-anthracenedimethanol is approximately one order of magnitude higher than with 9-anthracenemethanol.

  13. 聚乙烯接枝马来酸酐的工业生产技术研究%Production Technology of Polyethylene Grafted Maleic Anhydride

    Institute of Scientific and Technical Information of China (English)

    王益龙; 陈常明; 沈千新; 刘兴国

    2001-01-01

    Various methods of production of polyethylene grafted maleic anhydride (PE-g-MA) were compared by experiments. It was noted that the best way is reactive extrusion by means of reactive extruder. Its outstanding characteristics is that less free maleic anhydride exists in PE-g-MA and the process is automatic.It was also found that graft of HDPE was easier than that of LDPE,dicumyl peroxide had greater effect on graft rate than that of maleic anhydride.%通过实验比较了各种聚乙烯接枝马来酸酐的方法,发现利用反应式挤出机接枝最为理想,该方法的突出特点是产品中含游离态的马来酸酐少,工艺自动化及工作环境好等。通过实验还发现,HDPE比LDPE更易于接枝,接枝过程中过氧化物用量对接枝率的影响比MA用量对接枝率的影响大。

  14. Radiation grafting of styrene and maleic anhydride onto PTFE membranes and sequent sulfonation for applications of vanadium redox battery

    Energy Technology Data Exchange (ETDEWEB)

    Qiu Jingyi; Ni Jiangfeng [Beijing National Laboratory for Molecular Science, Department of Applied Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 (China); Zhai Maolin [Beijing National Laboratory for Molecular Science, Department of Applied Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 (China)], E-mail: mlzhai@pku.edu.cn; Peng Jing [Beijing National Laboratory for Molecular Science, Department of Applied Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 (China); Zhou Henghui [Beijing National Laboratory for Molecular Science, Department of Applied Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 (China)], E-mail: hhzhou@pku.edu.cn; Li Jiuqiang; Wei Genshuan [Beijing National Laboratory for Molecular Science, Department of Applied Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 (China)

    2007-11-15

    Using {gamma}-radiation technique, poly(tetrafluoroethylene) (PTFE) membrane was grafted with styrene (St) (PTFE-graft-PS) or binary monomers of St and maleic anhydride (MAn) (PTFE-graft-PS-co-PMAn), respectively. Then grafted membranes were further sulfonated with chlorosulfonic acid into ion-exchange membranes (denoted as PTFE-graft-PSSA and PTFE-graft-PSSA-co-PMAc, respectively) for application of vanadium redox battery (VRB). Micro-FTIR analysis indicated that PTFE was successfully grafted and sulfonated at the above two different conditions. However, a higher degree of grafting (DOG) was obtained in St/MAn binary system at the same dose due to a synergistic effect. Comparing with PTFE-graft-PSSA, PTFE-graft-PSSA-co-PMAc membrane showed higher water uptake and ion-exchange capacity (IEC) and lower area resistance (AR) at the same DOG. In addition, PTFE-graft-PSSA-co-PMAc with 6% DOG also showed a higher IEC and higher conductivity compared to Nafion membrane. Radiation grafting of PTFE in St/MAn binary system and sequent sulfonation is an appropriate method for preparing ion-exchange membrane of VRB.

  15. Separator Membrane from Crosslinked Poly(Vinyl Alcohol and Poly(Methyl Vinyl Ether-alt-Maleic Anhydride

    Directory of Open Access Journals (Sweden)

    Charu Vashisth Rohatgi

    2015-03-01

    Full Text Available In this work, we report separator membranes from crosslinking of two polymers, such as poly vinyl alcohol (PVA with an ionic polymer poly(methyl vinyl ether-alt-maleic anhydride (PMVE-MA. Such interpolymer-networked systems were extensively used for biomedical and desalination applications but they were not examined for their potential use as membranes or separators for batteries. Therefore, the chemical interactions between these two polymers and the influence of such crosslinking on physicochemical properties of the membrane are systematically investigated through rheology and by critical gel point study. The hydrogen bonding and the chemical interaction between PMVE-MA and PVA resulted in highly cross-linked membranes. Effect of the molecular weight of PVA on the membrane properties was also examined. The developed membranes were extensively characterized by studying their physicochemical properties (water uptake, swelling ratio, and conductivity, thermal and electrochemical properties using differential scanning calorimetry (DSC, dynamic mechanical analysis (DMA, thermo-gravimetric analysis (TGA and electrochemical impedance spectroscopy (EIS. The DSC study shows the presence of a single Tg in the membranes indicating compatibility of the two polymers in flexible and transparent films. The membranes show good stability and ion conductivity suitable for separator applications.

  16. Investigation of diode parameters using – and – characteristics of Al/maleic anhydride (MA)/p-Si structure

    Indian Academy of Sciences (India)

    A B Selçuk; S Bilge Ocak; G Kahraman; A H Selçuk

    2014-12-01

    Al/maleic anhydride (MA)/p-Si metal–polymer–semiconductor (MPS) structures were prepared on p-Si substrate by spin coating. Device parameters of Al/MA/p-Si structure have been determined by means of capacitance–voltage (–) and conductance–voltage (–) measurements between 700 kHz and 1.5 MHz and current–voltage (–) measurements at 300 K. The parameters of diode such as the ideality factor, series resistance, barrier height (BH) and flat band barrier height were calculated from the forward bias – characteristics. The investigation of interface states that density and series resistance from – and – characteristics in Al/MA/p-Si device has been reported. The frequency dependence of the capacitance could be attributed to trapping states. Several important device parameters such as the BH $\\phi_{b}$, fermi energy ($E_{F}$), diffusion voltage ($V_{D}$), donor carrier concentration ($N_{D}$) and space charge layer width ($W_{D}$) for the device have been obtained between 700 kHz and 1.5 MHz. The –, –- and –- characteristics confirm that the parameters like the BH, interface state density (it) and series resistance ($R_{s}$) of the diode are strongly dependent on the electrical parameters in the MPS structures.

  17. GRAFTING OF PEROXIDE-INITIATED MALEIC ANHYDRIDE ON SPHERICAL PE/PP IN-REACTOR BLEND GRANULES

    Institute of Scientific and Technical Information of China (English)

    Yan-zhong Zhang; Zhi-qiang Fan; Bai-geng Wu; Jun-ting Xu; Qi Wang

    2004-01-01

    Spherical polyethylene/polypropylene (PE/PP) in-reactor blend granules with various ethylene/propylene molar ratios and high porosity were synthesized using a high yield TiCl4/MgCl2 supported catalyst. A solution of benzoyl peroxide (BPO)/maleic anhydride (MAH)/xylene (interfacial reagent) or BPO/MAH/St (comonomer) was absorbed onto the PE/PP inreactor blend granules, and solid phase graft polymerization of MAH on PE/PP was conducted. The amount of grafted MAH on PE/PP was measured through chemical titration. The results showed that solid phase graft polymerization of MAH in PE/PP in-reactor blend granules produced graft copolymer with high amount of grafted MAH, and the amount of grafted MAH was raised slightly when St was introduced as comonomer. The graft in-reactor blend was fractionated into five fractions through temperature-gradient extraction fractionation (TGEF), and the fractions were analyzed by FTIR. The results revealed that MAH is mainly grafted on the PE segments, whereas MAH was predominantly grafted on the PP segments when St was present in the graft polymerization system. In addition, the final product is still in the form of regular spherical granules, which is beneficial for industrial processing.

  18. Olefin-maleic-anhydride copolymer based additives: a novel approach for compatibilizing blends of waste polyethylene and crumb rubber.

    Science.gov (United States)

    Tóth, Balázs; Varga, Csilla; Bartha, László

    2015-04-01

    In our work processing conditions and mechanical properties of waste polyethylene (PE)/crumb rubber (CR) blends have been improved by new types of compatibilizing additives synthesized from experimental olefin-maleic-anhydride copolymers at our laboratory. Compatibilizing additives have been introduced into the PE/CR blends in 0.2 wt% while CR concentration has been varied between 10 and 50 wt%. For comparison of the effects commercially available MA-g-PO type compatibilizing additives have also been applied. Tensile and Charpy impact tests of the compression moulded samples have been carried out. Several experimental additives have enhanced properties of the PE/CR blends either from the point of view of tensile or Charpy impact strength while commercial additives have had improving effects only on one of the abovementioned mechanical properties but not for both of them simultaneously. Since good mechanical properties could be achieved by our experimental compatibilizers good adhesion in the waste PE/CR samples have been considered and was proven by SEM graphs either.

  19. Adsorption of heavy metal ions and azo dyes by crosslinked nanochelating resins based on poly(methylmethacrylate-co-maleic anhydride

    Directory of Open Access Journals (Sweden)

    M. Ghaemy

    2014-03-01

    Full Text Available Chelating resins are suitable materials for the removal of heavy metals in water treatments. A copolymer, Poly(MMA-co-MA, was synthesized by radical polymerization of maleic anhydride (MA and methyl methacrylate (MMA, characterized and transformed into multifunctional nanochelating resin beads (80–150 nm via hydrolysis, grafting and crosslink reactions. The resin beads were characterized by swelling studies, field emission scanning electron microscopy (FESEM and Fourier transform infrared spectroscopy (FTIR. The main purpose of this work was to determine the adsorption capacity of the prepared resins (swelling ratio ~55% towards metal ions such as Hg2+, Cd2+, Cu2+ from water at three different pH values (3, 6 and 9. Variations in pH and types of metal ions have not significantly affected the chelation capacity of these resins. The maximum chelation capacity of one of the prepared resin beads (Co-g-AP3 for Hg2+ was 63, 85.8 and 71.14 mg/g at pH 3, 6 and 9, respectively. Approximately 96% of the metal ions could be desorbed from the resin. Adsorption capacity of these resins towards three commercial synthetic azo dyes was also investigated. The maximum adsorption of dye AY42 was 91% for the resin Co-g-AP3 at room temperature. This insures the applicability of the synthesized resins for industrial applications.

  20. Preparation of High Density Polyethylene/Waste Polyurethane Blends Compatibilized with Polyethylene-Graft-Maleic Anhydride by Radiation

    Directory of Open Access Journals (Sweden)

    Jong-Seok Park

    2015-04-01

    Full Text Available Polyurethane (PU is a very popular polymer that is used in a variety of applications due to its good mechanical, thermal, and chemical properties. However, PU recycling has received significant attention due to environmental issues. In this study, we developed a recycling method for waste PU that utilizes the radiation grafting technique. Grafting of waste PU was carried out using a radiation technique with polyethylene-graft-maleic anhydride (PE-g-MA. The PE-g-MA-grafted PU/high density polyethylene (HDPE composite was prepared by melt-blending at various concentrations (0–10 phr of PE-g-MA-grafted PU. The composites were characterized using fourier transform infrared spectroscopy (FT-IR, and their surface morphology and thermal/mechanical properties are reported. For 1 phr PU, the PU could be easily introduced to the HDPE during the melt processing in the blender after the radiation-induced grafting of PU with PE-g-MA. PE-g-MA was easily reacted with PU according to the increasing radiation dose and was located at the interface between the PU and the HDPE during the melt processing in the blender, which improved the interfacial interactions and the mechanical properties of the resultant composites. However, the elongation at break for a PU content >2 phr was drastically decreased.

  1. Hydrolysis and stability of thin pulsed plasma polymerised maleic anhydride coatings

    DEFF Research Database (Denmark)

    Drews, Joanna Maria; Launay, Héléne; Hansen, Charles M.

    2008-01-01

    were obtained at constant plasma power by adjusting the polymerisation time. The results show that the hydrolysis resistance of the modified layer is determined by the power used in the plasma polymerisation, while changes in the chemistry of the modified layer are insignificant....

  2. Comparative Study Of The Preparation Of Maleic Anhydride-g-Polypropylene By Two Grafting Processes Using Peroxide; Estudo comparativo de dois processos de graftizacao de polipropileno com anidrido maleico utilizando peroxidos

    Energy Technology Data Exchange (ETDEWEB)

    Sakahara, R.M.; Wang, S.H., E-mail: sakahara@usp.b, E-mail: wangshui@usp.b [Universidade de Sao Paulo (EPUSP), SP (Brazil). Escola Politecnica. Dept. de Engenharia Metalurgica e de Materiais

    2010-07-01

    The Polypropylene grafting with Maleic anhydride is a thoroughly known technique. Its wide application is due, mainly,to the controlled changing in the polarity of this polymer, which increases the interfacial adhesion in blends and compounds. In this study, two grafting processes were compared. In the first, the maleic anhydride was grafted on polypropylene in a solution batch process, carried out in a round-bottom vessel. The second approach was carried out by reactive extrusion of polypropylene in the presence of peroxide and maleic anhydride. The samples thus prepared were characterized by DSC, TGA, FTIR, WAXS, EDS e SEM. It was possible to conclude that the solution technique was more efficient than the reactive extrusion; however the later was easier to accomplish due to the high viscosity of PP. (author)

  3. EFSA NDA Panel (EFSA Panel on Dietetic Products, Nutrition and Allergies), 2013. Scientific Opinion on the safety of ―Methyl Vinyl Ether-Maleic Anhydride Copolymer‖ (chewing gum base ingredient) as a Novel Food ingredient

    DEFF Research Database (Denmark)

    Tetens, Inge

    Following a request from the European Commission, the EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA) was asked to deliver a scientific opinion on the safety of “methyl vinyl ether-maleic anhydride copolymer (Gantrez SF)” as a novel food ingredient in the context of Regulation (EC......) No 258/97. The novel food ingredient Gantrez SF is an anhydrous copolymer formed by the reaction of methyl vinyl ether (MVE) and maleic anhydride (MAN) under appropriate conditions. The Panel considers that the information provided on the specifications, stability and production process do not raise...

  4. Cu(II), Zn(II) andMn(II) complexes of poly(methyl vinyl ether-alt-maleic anhydride). Synthesis, characterization and thermodynamic parameters

    Indian Academy of Sciences (India)

    Hidayet Mazi; Ali Gulpinar

    2014-01-01

    The complexes of poly(methyl vinyl ether-alt-maleic anhydride) (poly(MVE-alt-MA)) with Zn(II), Mn(II) and Cu(II) ions were synthesized from the reaction of the aqueous solution of copolymer and metal(II) chlorides at different temperatures ranging from 25° to 40°C. Elemental analysis of themetal-polymer complexes suggests that the metal to ligand ratio is 1:1. The formation constants of each complex were determined by the mol-ratio method. UV-Vis studies showed that the complex formation tendency increased in the following order: Zn(II) > Cu(II) > Mn(II). This order was confirmed by the Irving-William series and Pearson’s classification. The IR spectral data indicated the metal ions to be coordinated through the hydroxyl groups of the hydrolysed maleic anhydride. The intrinsic viscosity and thermal properties of the copolymer and metal-polymer complexes and their thermal stability are discussed.

  5. Mechanosynthesis and mechanochemical treatment of bismuth doped vanadium phosphorus oxide catalysts for the partial oxidation of n-butane to maleic anhydride

    Institute of Scientific and Technical Information of China (English)

    Y H.Taufiq-Yap; Y C.Wong; Y Kamiya; W.J.Tang

    2008-01-01

    Three Bi-doped vanadyl pyrophosphate catalysts were prepared via dihydrate route(VPD method),which consisted of different preparation methods including mechanosvnthesis,mechanochemical treatment,and the conventional reflux method.The catalysts produced by the above three methods were characterized by x-ray diffraction(XRD),scanning electron microscopy(SEM),and temperature programmed reduction(TPR).Catalytic evaluation for the partial oxidation of n-butane to maleic anhydride (MA) was also carried out.The XRD patterns of all the Bi-doped catalysts showed the main peaks of pyrophosphate phase.Lower intensity peaks were observed for the mechanochemically treated Bi-doped catalyst(VPDBiMill)with two additional small DeakS corresponding to the presence of a small amount of V5+ phase.The TPR profiles showed that the highest amount of active oxygen species.i.e.V4+-O- pair,responsible for n-butane activation,was removed from VPDBiMill.Furthermore.from the catalytic test results.the graph of selectivity to MA as a function of the conversion of n-butane demonstrated that VPDBiMill was the most selective catalyst.This suggests that the mechanochemical treatment of vanadium phosphate catalyst(VPDBiMill)is a potential method to improve the catalytic properties for the partial oxidation of n-butane to maleic anhydride.

  6. Influência da estrutura de diferentes copolímeros de etileno e a-olefinas na funcionalização com anidrido maleico Influence of structure of ethylene a-olefins copolymers in functionalization with maleic anhydride

    Directory of Open Access Journals (Sweden)

    Carlota H. F. Maurano

    1998-01-01

    Full Text Available A funcionalização de copolímeros de etileno e a-olefinas com anidrido maleico (AM foi realizada em solução de xileno com peróxido de dibenzoíla (DBP como iniciador. Foi estudado o efeito das diferentes estruturas dos copolímeros, como número e comprimento de ramificação, na incorporação do AM. A funcionalização também foi realizada em estado fundido utilizando-se um misturador Rheomix 600 e uma extrusora Rheocord 9000 da Haake. A funcionalidade foi determinada por titulometria de neutralização e os produtos foram caracterizados por espectroscopia na região do infravermelho (FT-IR e por cromatografia de permeação em gel (GPC. A funcionalidade dos copolímeros de etileno com 1-hexeno aumentou com o aumento do teor de comonômero e dos copolímeros com 1-octeno e 1-deceno aumentou com o aumento do teor de a-olefina até um máximo, decrescendo e mantendo-se constante.Chemical modification of ethylene a-olefins copolymers with maleic anhydride was studied by radical reaction in solution, melt mixing and extrusion. The effect of copolymer structure, as the amount and length of the branches, was evaluated on the MA incorporation. The reactions were also achieved in Rheomix 600 (Haake mixer and Rheocord 9000 (Haake extruder. Functionalization was determinated by titration and modified ethylene a-olefins copolymers were characterized by Infrared Spectroscopy and Gel Permeation Chromatography. The maleic anhydride incorporation in the ethylene-hexene copolymers increases with the amount of a-olefin. Functionalization of ethylene-octene and ethylene-decene comonomers increases with increasing peroxide concentration until a maximum and then decreases up to a constant value.

  7. The Formation of Polycomplexes of Poly(Methyl Vinyl Ether-Co-Maleic Anhydride and Bovine Serum Albumin in the Presence of Copper Ions

    Directory of Open Access Journals (Sweden)

    Karahan Mesut

    2014-09-01

    Full Text Available The binary and ternary complex formations of poly(methyl vinyl ether-co-maleic anhydride (PMVEMA with copper ions and with bovine serum albumin (BSA in the presence of copper ions in phosphate buffer solution at pH = 7 were examined by the techniques of UV-visible, fluorescence, dynamic light scattering, atomic force microscopy measurements. In the formation of binary complexes of PMVEMA-Cu(II, the addition of copper ions to the solution of PMVEMA in phosphate buffer solution at pH = 7 forms homogeneous solutions when the molar ratio of Cu(II/MVEMA is 0.5. Then the formations of ternary complexes of PMVEMA-Cu(II-BSA were examined. Study analysis revealed that the toxicities of polymer-metal and polymer-metal-protein mixture solutions depend on the nature and ratio of components in mixtures.

  8. The application of ASPEN PLUS software on the simulation of solvent absorption in maleic anhydride plant%ASPEN PLUS在顺酐回收工艺模拟中的应用

    Institute of Scientific and Technical Information of China (English)

    张文彪; 屈一新

    2011-01-01

    ASPEN PLUS has been used to simulate the maleic anhydride absorption process.The Soave-Redlich-Kwong equation modified with K - D mixing rule has been used to get thermodynamic calculations, and the missing physical parameters of components in the database have been supplied from literature to obtain a more accurate simulation results.With the toolbox of sensitivity analysis, the optimal operating parameters have been generated: the optimal temperature of absorbent fed into the tower is 40 - 45 ℃; the optimal temperature of maleic anhydride mixture fed into the tower is 48 - 56 ℃; the optimal flow rate of circulating absorbent is 24 214 kg/h.According to the analysis results, an alteration project is presented which can save 5501.948 MJ/h and reduce the expense of one heat exchanger compared to the original process.%应用化工流程模拟软件ASPEN PLUS对顺酐溶剂回收工艺进行模拟.使用经K-D混合规则修正了的Soave-Redlich-Kwong方程进行热力学计算,并对数据库中缺失的物性参数进行补充以获得更准确的模拟结果.通过灵敏度分析,得到最优的操作参数:吸收剂入塔最优温度40~45℃,顺酐混合气人塔最优温度48~56℃,吸收剂循环流量24 214 kg/h.根据分析优化结果对原工艺提出改造方案,经过模拟计算预测,改造后的工艺与原工艺相比可以节省能量5 501.948 MJ/h,同时减少一个换热器的建造和维护费用.

  9. Solvent effects in acid-catalyzed dehydration of the Diels-Alder cycloadduct between 2,5-dimethylfuran and maleic anhydride

    Science.gov (United States)

    Salavati-fard, Taha; Caratzoulas, Stavros; Doren, Douglas J.

    2017-03-01

    Dehydration of the cycloadduct produced from the Diels-Alder reaction between 2,5-dimethylfuran and maleic anhydride to 3,6-dimethylphthalic anhydride exemplifies an important step in producing platform chemicals from biomass. The mechanisms of dehydration and catalytic effects of Lewis and Brønsted acids are investigated with density functional theory. The uncatalyzed reaction has a very high activation barrier (68.7 kcal/mol) in the gas phase and it is not significantly affected by solvation. With a Lewis acid catalyst, modeled as an alkali ion, the activation barriers are reduced, but intermediates are also stabilized. The net effect in vacuum is that the energetic span, or apparent activation energy of the catalytic cycle, is 77.9 kcal/mol, even higher than the barrier in the uncatalyzed case. In solution, however, the energetic span is reduced by as much as 20 kcal/mol, due to differences in the solvation energy of the transition states and intermediates. In the case of a Brønsted acid catalyst, modeled as a proton, the gas phase transition state energies are reduced even more than in the Lewis acid case, and there is no strong stabilization of the intermediates. The energetic span in vacuum is only 13.8 kcal/mol and is reduced even further in solution. Brønsted acid catalysis appears to be the preferred mechanism for dehydration of this cycloadduct. Since the Diels-Alder reaction that produced the molecule has previously been shown to be catalyzed by Brønsted acids, this suggests that a single catalyst could be used to accelerate both steps.

  10. Pre-irradiation grafting of styrene and maleic anhydride onto PVDF membrane and subsequent sulfonation for application in vanadium redox batteries

    Energy Technology Data Exchange (ETDEWEB)

    Qiu, Jingyi; Zhai, Maolin; Ni, Jiangfeng; Zhou, Henghui; Peng, Jing; Li, Jiuqiang; Wei, Genshuan [Beijing National Laboratory for Molecular Science (BNLMS), Department of Applied Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 (China); Zhao, Long [Department of Biological and Chemical Engineering, Gunma University, Tenjin-cho, Kiryu, Gunma 376-8515 (Japan)

    2008-03-01

    A poly(vinylidene difluoride) (PVDF) membrane was grafted with styrene (St) and maleic anhydride (MAn) using an electron-beam-induced pre-irradiation grafting technique. The grafted membrane (PVDF-g-PS-co-PMAn) was then sulfonated and hydrolyzed to give an ion exchange membrane (denoted as PVDF-g-PSSA-co-PMAc) for vanadium redox flow batteries (VRB) use. Micro-FTIR analysis indicated that PVDF was successfully grafted and sulfonated at the above condition, and the membrane with a high grafting yield (GY) can be easily prepared in a St/MAn binary system at low dose due to a synergistic effect. The water uptake and ion exchange capacity (IEC) of the PVDF-g-PSSA-co-PMAc membrane increased with GY, so too did the conductivity. At a GY of 33.6%, the resulting PVDF-g-PSSA-co-PMAc membrane showed a much higher IEC and conductivity than a conventional Nafion117 membrane, and a much lower permeability of vanadium ions: ca. 1/11 to 1/16 of that through Nafion117. Open circuit voltage measurements showed that the VRB assembled with the PVDF-g-PSSA-co-PMAc membrane maintained values above 1.3 V after a period of 33 h, which was much longer than that with the Nafion117 membrane. It is expected that this work provides a new approach for the fabrication of ion exchange membranes for VRB. (author)

  11. Nanocomposites of PA6/ABS blends compatibilized with styrene-maleic anhydride copolymer;Nanocompositos de blendas de PA6/ABS compatibilizadas com copolimero estireno-anidrido maleico

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Amanda D. de, E-mail: amandaengmat@yahoo.com.b [Universidade Federal de Sao Carlos (PPG-CEM/UFSCar), SP (Brazil). Programa de Pos-Graduacao em Ciencia e Engenharia de Materiais; Araujo, Edcleide M. [Universidade Federal de Campina Grande (UFCG), PB (Brazil); Pessan, Luiz A. [Universidade Federal de Sao Carlos (DEMa/UFSCar), SP (Brazil). Dept. de Engenharia de Materiais

    2009-07-01

    To achieve a balance between stiffness and toughness, ternary nanocomposites based on blends of polyamide 6 (PA6) and acrylonitrile-butadiene-styrene (ABS) were prepared by the melt intercalation using the organoclay Cloisite{sup R} 30B (OMMT) and the styrene-maleic anhydride copolymer (SMA) as compatibilizer. Four blending sequences were used to prepare studied systems and their mechanical properties studied through the Young's modulus and notched Izod impact. It was observed that the materials prepared by all blending sequences studied showed an increase in the Young's modulus compared to the neat PA6. However, a decrease in the toughness was observed for the systems with the addition of the organoclay. The DRX results showed an intercalated structure for the some systems that used ABS in their compositions. HDT measurements of the nanocomposites showed an increase in this property compared to the neat PA6. The use of nanoclay lead to a reinforcement of the polymeric matrix. (author)

  12. Preparation of Poly-(Methyl vinyl ether-co-maleic Anhydride Nanoparticles by Solution-Enhanced Dispersion by Supercritical CO2

    Directory of Open Access Journals (Sweden)

    Yong-Qiang Kang

    2012-10-01

    Full Text Available The supercritical CO2-based technologies have been widely used in the formation of drug and/or polymer particles for biomedical applications. In this study, nanoparticles of poly-(methyl vinyl ether-co-maleic anhydride (PVM/MA were successfully fabricated by a process of solution-enhanced dispersion by supercritical CO2 (SEDS. A 23 factorial experiment was designed to investigate and identify the significance of the processing parameters (concentration, flow and solvent/nonsolvent for the surface morphology, particle size, and particle size distribution of the products. The effect of the concentration of PVM/MA was found to be dominant in the results regarding particle size. Decreasing the initial solution concentration of PVM/MA decreased the particle size significantly. After optimization, the resulting PVM/MA nanoparticles exhibited a good spherical shape, a smooth surface, and a narrow particle size distribution. Fourier transform infrared spectroscopy (FTIR spectra demonstrated that the chemical composition of PVM/MA was not altered during the SEDS process and that the SEDS process was therefore a typical physical process. The absolute value of zeta potential of the obtained PVM/MA nanoparticles was larger than 40 mV, indicating the samples’ stability in aqueous suspension. Analysis of thermogravimetry-differential scanning calorimetry (TG-DSC revealed that the effect of the SEDS process on the thermostability of PVM/MA was negligible. The results of gas chromatography (GC analysis confirmed that the SEDS process could efficiently remove the organic residue.

  13. Crystallization and melting behavior of {beta}-nucleated isotactic polypropylene/polyamide 6 blends with maleic anhydride grafted polyethylene-vinyl acetate as a compatibilizer

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Zhugen [Materials Science Institute, School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Key Laboratory of Polymeric Composites and Functional Materials of the Ministry of Education, Guangzhou 510275 (China); Institut des Nanotechnologies de Lyon, UMR 5270 CNRS, Ecole centrale de Lyon, Equipe Chimie et Nanobiotechnologies, 36 Avenue Guy-de-Collongue, 69134 Ecully (France); Mai, Kancheng, E-mail: cesmkc@mail.sysu.edu.cn [Materials Science Institute, School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Key Laboratory of Polymeric Composites and Functional Materials of the Ministry of Education, Guangzhou 510275 (China)

    2010-11-20

    {beta}-Nucleated isotactic polypropylene ({beta}-iPP) blend with maleic anhydride grafted polyethylene-vinyl acetate (EVA-g-MA) and {beta}-iPP/polyamide (PA) 6 blend, as well as its compatibilized version with EVA-g-MA as a compatibilizer were prepared with an internal mixer. Analysis from differential scanning calorimeter (DSC) and wide angle X-ray diffraction (WAXD) indicates that the addition of EVA-g-MA into {beta}-nucleated iPP decreases the crystallization temperature (T{sub c}{sup p}) of PP, but it has no pronounced influence on the {beta}-crystal content for {beta}-nucleated iPP. For {beta}-nucleated iPP/PA6 blends, PA6 obviously decreases the {beta}-crystal content. However, the addition of EVA-g-MA is quite benefit for the formation of {beta}-crystal in {beta}-nucleated iPP/PA6 blends and the {beta}-crystal content increases with increasing EVA-g-MA content. It is suggested that the nucleating agent mainly disperses in the PA6 phase and/or the interface between iPP and PA6 in iPP/PA6 blend, which was proved by etching the blends with sulfuric acid and experimental facts from SEM.

  14. Letrozole dispersed on poly (vinyl alcohol) anchored maleic anhydride grafted low density polyethylene: a controlled drug delivery system for treatment of breast cancer.

    Science.gov (United States)

    Siddiqa, Akhtar Jahan; Chaudhury, Koel; Adhikari, Basudam

    2014-04-01

    The present work focuses on the design of a drug delivery system for systemic, controlled release of the poorly soluble breast cancer drug, letrozole. The drug delivery system was prepared in two steps: a low density polyethylene (LDPE) substrate surface was grafted with maleic anhydride (MA) via solution grafting technique. Next, the grafted substrate was used to anchor a hydrophilic polymeric drug release system consisting of poly (vinyl alcohol) (PVA). The PVA anchored MA grafted LDPE (PVA/MA-g-LDPE) drug release system was used for the controlled release of letrozole. This system was characterized using ATR-FTIR spectrophotometry, surface profilometry, and scanning electron microscopy. Biocompatibility studies were also carried out. In vitro release studies of letrozole from the system were performed in distilled water and phosphate buffer saline (PBS) at 37°C. Release of ∼90% letrozole from hydrophilic PVA matrix was observed within a period of 35 days. A high correlation coefficient (R(2)=0.99) was seen between the release of letrozole in distilled water and PBS. Cytotoxicity studies using MTT colorimetric assay suggested that all samples were biocompatible. It is concluded that the letrozole delivery system appears to overcome the limitations associated with letrozole by providing enhanced drug dissolution rate, controlled release and improved bioavailability of the incorporated drug and, therefore, seems to have extended therapeutic effects.

  15. Promotional Effect of CoO(OH)on Selective Hydrogenation of Maleic Anhydride to γ-Butyrolactone over Supported Ruthenium Catalyst

    Institute of Scientific and Technical Information of China (English)

    Zhou Yafen; Wang Qing; Wang Manman; Yang Wenjuan; Zhou Limei; Ma Xiaoyan

    2015-01-01

    A decorated ruthenium catalyst was prepared by the coprecipitation method and used for the selective hydro-genation of maleic anhydride (MA) to γ-butyrolactone (GBL). The as-prepared catalyst was characterized by XRD, TG-DTG and N2 adsorption techniques. The characterization tests revealed that the catalyst carrier was composed of monoclinic zirconia (m-ZrO2) and hydroxyl cobalt oxide (CoO(OH)). The hydrogenation results showed that the content of CoO(OH), the reaction temperature, the hydrogen pressure and the reaction time signiifcantly affectedthe catalytic selectivity to GBL. The promotional effect of CoO(OH) was remarkable, which led to an obvious increase in GBL selectivity. An 100% MA conversion and 92.0% selectivity to GBL were achieved over the Ru/ZrO2-CoO(OH)(35%) catalyst in water solvent under the conditions involving a reaction temperature of 180℃, a hydrogen pressure of 3.0 MPa, and a reaction time of 6 h.

  16. Blending of Low-Density Polyethylene and Poly-Lactic Acid with Maleic Anhydride as A Compatibilizer for Better Environmentally Food-Packaging Material

    Science.gov (United States)

    Setiawan, A. H.; Aulia, F.

    2017-05-01

    The common conventional food packaging materialsare using a thin layer plastic or film, which is made of a synthetic polymer, such as Low-Density Poly Ethylene (LDPE). However, the use of these polymers hasan adverse impact on the environment, because the synthetic polymersare difficult to degrade naturally. Poly-Lactic Acid (PLA) is a biodegradable polymer that can be substituted to synthetic polymers. Since LDPE and PLA have a difference in polarity, therefore the first step of research is to graft them with maleic anhydride (MAH) for increasing the properties of its miscibility. The interaction between them is confirmed by FTIR; whereas the environment issueis characterized by the water adsorption and biodegradability. The FTIR spectra indicated that there had been an interaction between LDPE and MAH and LDPE/LDPE-g-MAH/PLA blend. Increasing PLA content in the blend affected to the increasing in their water absorption and biodegradable. Poly-blend with 20% PLA content was the optimum composition for environmentally food packaging.

  17. Aluminum-phthalocyanine chloride associated to poly(methyl vinyl ether-co-maleic anhydride) nanoparticles as a new third-generation photosensitizer for anticancer photodynamic therapy.

    Science.gov (United States)

    Muehlmann, Luis Alexandre; Ma, Beatriz Chiyin; Longo, João Paulo Figueiró; Almeida Santos, Maria de Fátima Menezes; Azevedo, Ricardo Bentes

    2014-01-01

    Photodynamic therapy is generally considered to be safer than conventional anticancer therapies, and it is effective against different kinds of cancer. However, its clinical application has been significantly limited by the hydrophobicity of photosensitizers. In this work, a system composed of the hydrophobic photosensitizer aluminum-phthalocyanine chloride (AlPc) associated with water dispersible poly(methyl vinyl ether-co-maleic anhydride) nanoparticles is described. AlPc was associated with nanoparticles produced by a method of solvent displacement. This system was analyzed for its physicochemical characteristics, and for its photodynamic activity in vitro in cancerous (murine mammary carcinoma cell lineage 4T1, and human mammary adenocarcinoma cells MCF-7) and noncancerous (murine fibroblast cell lineage NIH/3T3, and human mammary epithelial cell lineage MCF-10A) cell lines. Cell viability and the elicited mechanisms of cell death were evaluated after the application of photodynamic therapy. This system showed improved photophysical and photochemical properties in aqueous media in comparison to the free photosensitizer, and it was effective against cancerous cells in vitro.

  18. Plasma-enhanced CVD of functional coatings in Ar/maleic anhydride/C2H2 homogeneous dielectric barrier discharges at atmospheric pressure

    Science.gov (United States)

    Zajíčková, Lenka; Jelínek, Petr; Obrusník, Adam; Vodák, Jiří; Nečas, David

    2017-03-01

    In this contribution, we focus on the general problems of plasma-enhanced chemical vapor deposition in atmospheric pressure dielectric barrier discharges, i.e. deposition uniformity, film roughness and the formation of dust particles, and demonstrate them on the example of carboxyl coatings prepared by co-polymerization of acetylene and maleic anhydride. Since the transport of monomers at atmospheric pressure is advection-driven, special attention is paid to the gas dynamics simulations, gas flow patterns, velocity and residence time. By using numerical simulations, we design an optimized gas supply geometry capable of synthesizing uniform layers. The selection of the gas mixture containing acetylene was motivated by two of its characteristics: (i) suppression of filaments in dielectric barrier discharges, and (ii) improved film cross-linking, keeping the amount of functional groups high. However, acetylene discharges are prone to the formation of nanoparticles that can be incorporated into the deposited films, leading to their high roughness. Therefore, we also discuss the role of the gas composition, the spatial position of the substrate with respect to gas flow and the deposition time on the topography of the deposited films.

  19. Sub-micronic capsules based on gelatin and poly(maleic anhydride-alt-vinyl acetate) obtained by interfacial condensation with potential biomedical applications.

    Science.gov (United States)

    Iurea, Delia Mihaela; Peptu, Cătălina Anişoara; Chailan, Jean-François; Carriere, Pascal; Popa, Marcel

    2013-06-01

    New sub-micronic capsules based on a copolymer of maleic anhydride-alt-vinyl acetate and a natural polymer (gelatin) using an interfacial condensation method were obtained. Sub-micronic capsules were characterized by Fourier Transform infrared spectroscopy (FTIR), dynamic light scattering (DLS) method, zeta-potential, scanning electron microscopy (SEM) and atomic force microscopy (AFM). The thermal properties were investigated by thermogravimetric analysis (TGA). According to some parameters of the synthesis reaction (polymer weight ratio, acetone/water ratio, surfactant concentration), the mean diameter of the sub-micronic capsules can be tuned from 200 to 760 nm. The sub-micronic capsules show a higher agglomeration tendency as the amount of gelatin in their composition increases. The swelling capacity in aqueous solutions is dependent on the composition and size of the sub-micronic capsules, decreasing with their diameter and gelatin composition. The drug loading and release capacity was studied using Penicillin G (sodium salt) (PG), and it has been proved that it is influenced by the sub-micronic capsules morphology induced by preparation parameters. Encapsulation and controlled release of small molecule were successfully carried out, demonstrating the potential biomedical applications of these new easily obtained sub-micronic capsules.

  20. Enhancement of the Mechanical Properties of Basalt Fiber-Wood-Plastic Composites via Maleic Anhydride Grafted High-Density Polyethylene (MAPE Addition

    Directory of Open Access Journals (Sweden)

    Yun Lu

    2013-06-01

    Full Text Available This study investigated the mechanisms, using microscopy and strength testing approaches, by which the addition of maleic anhydride grafted high-density polyethylene (MAPE enhances the mechanical properties of basalt fiber-wood-plastic composites (BF-WPCs. The maximum values of the specific tensile and flexural strengths are achieved at a MAPE content of 5%–8%. The elongation increases rapidly at first and then continues slowly. The nearly complete integration of the wood fiber with the high-density polyethylene upon MAPE addition to WPC is examined, and two models of interfacial behavior are proposed. We examined the physical significance of both interfacial models and their ability to accurately describe the effects of MAPE addition. The mechanism of formation of the Model I interface and the integrated matrix is outlined based on the chemical reactions that may occur between the various components as a result of hydrogen bond formation or based on the principle of compatibility, resulting from similar polarity. The Model I fracture occurred on the outer surface of the interfacial layer, visually demonstrating the compatibilization effect of MAPE addition.

  1. 含顺丁烯二酸酐结构化合物抑制黑曲霉性能的研究%Research on Inhibition of the Compound with Maleic Anhydride Structure on the Performance of Aspergillus niger

    Institute of Scientific and Technical Information of China (English)

    金侃华; 陈小龙

    2009-01-01

    [Objective]The aim was to research the relationships between the side chain of maleic anhydride structure compounds and inhibition effect on Aspergillus niger. [Method]Choosing 7 kinds of common compounds with maleic anhydride structure and tautomycin, the test of inhibiting Aspergillus niger was carried out by using oxford cup method. [Result]Diphenylmaleic anhydride with the concentration of 10 g/L had a good inhibition on Aspergillus niger, while tautomycin with the lower concentration of 1 g/L also had a considerable inhibition effect. [Conclusions]The side chain of maleic anhydride structure compounds containing chlorine could promote the inhibition effect on Aspergillus niger, and containing benzene couldn't enhance the activity of inhibition on Aspergillus niger.%[目的]研究含顺丁烯二酸酐结构化合物侧链结构与抑制黑曲霉效果的关系. [方法]选取7种常见含顺丁烯二酸酐结构化合物以及变构霉素,用牛津杯法进行抑制黑曲霉试验.[结果]3, 6-二氯邻苯二甲酸酐在10 g/L浓度下对黑曲霉有较好的抑制作用,变构霉素在1 g/L 浓度下仍对黑曲霉有一定的抑制作用. [结论]含顺丁烯二酸酐结构化合物侧链含有氯对抑制黑曲霉有促进作用,而含有苯环则不能增强其对抑制黑曲霉的活性.

  2. Tannic Acid as a Bio-Based Modifier of Epoxy/Anhydride Thermosets

    OpenAIRE

    Xiaoma Fei; Fangqiao Zhao; Wei Wei; Jing Luo; Mingqing Chen; Xiaoya Liu

    2016-01-01

    Toughening an epoxy resin by bio-based modifiers without trade-offs in its modulus, mechanical strength, and other properties is still a big challenge. This paper presents an approach to modify epoxy resin with tannic acid (TA) as a bio-based feedstock. Carboxylic acid-modified tannic acid (TA–COOH) was first prepared through a simple esterification between TA and methylhexahydrophthalic anhydride, and then used as a modifier for the epoxy/anhydride curing system. Owing to the chemical modifi...

  3. In situ preparation of a magnetic composite during functionalization of poly[maleic anhydride-co-3,9-divinyl-2,4,8,10-tetraoxaspiro(5.5)undecane] with erythritol

    Energy Technology Data Exchange (ETDEWEB)

    Neamtu, Iordana; Chiriac, Aurica P., E-mail: achiriac1@yahoo.com; Nita, Loredana E.; Tudorachi, Nita; Diaconu, Alina [“Petru Poni” Institute of Macromolecular Chemistry (Romania)

    2015-06-15

    New magnetic hybrid composites were prepared, in situ, during the functionalization of poly[maleic anhydride-co-3,9-divinyl-2,4,8,10-tetraoxaspiro(5.5)undecane] copolymer, by opening the anhydride ring with erythritol and by introducing magnetic nanoparticles into the polymeric matrix. The procedure allows for magnetic nanocomposite preparation. More than that, the new polymeric matrices owing to their suitable and specific functionalities are anticipated to be used for further link of biological molecules via the maleic anhydride moiety and the polyol presence. The hybrid composites are analyzed by infrared absorption spectrometry, dynamic light scattering (DLS), TG-DTG analysis, X-ray diffraction, SEM, TEM, and vibrating sample magnetometry. Examination of the magnetic composites by DLS analysis shows that the material consists mostly of particles with mean sizes between 295 and 342 nm, depending on the magnetite type in synthesis. The obtained results indicate the magnetite encapsulation and the interactions established with the polymeric matrix that lead to carbonyl band shifting in FTIR spectra, composite particle size decreasing, and influence on XRD and magnetic behavior data. The report of magnetization demonstrates that the prepared nanocomposites are superparamagnetic.

  4. Preparation, characterization and thermal properties of styrene maleic anhydride copolymer (SMA)/fatty acid composites as form stable phase change materials

    Energy Technology Data Exchange (ETDEWEB)

    Sari, Ahmet; Alkan, Cemil; Karaipekli, Ali; Oenal, Adem [Department of Chemistry, Gaziosmanpasa University, 60240, Tokat (Turkey)

    2008-02-15

    Fatty acids such as stearic acid (SA), palmitic acid (PA), myristic acid (MA) and lauric acid (LA) are promising phase change materials (PCMs) for latent heat thermal energy storage (LHTES) applications, but high cost is the major drawback of them, limiting their utility area in thermal energy storage. The use of fatty acids as form stable PCMs will increase their feasibilities in practical applications due to the reduced cost of the LHTES system. In this regard, a series of styrene maleic anhydride copolymer (SMA)/fatty acid composites, SMA/SA, SMA/PA, SMA/MA, and SMA/LA, were prepared as form stable PCMs by encapsulation of fatty acids into the SMA, which acts as a supporting material. The encapsulation ratio of fatty acids was as much as 85 wt.% and no leakage of fatty acid was observed even when the temperature of the form stable PCM was over the melting point of the fatty acid in the composite. The prepared form stable composite PCMs were characterized using optic microscopy (OM), viscosimetry and Fourier transform infrared (FT-IR) spectroscopy methods, and the results showed that the SMA was physically and chemically compatible with the fatty acids. In addition, the thermal characteristics such as melting and freezing temperatures and latent heats of the form stable composite PCMs were measured by using the differential scanning calorimetry (DSC) technique, which indicated they had good thermal properties. On the basis of all the results, it was concluded that form stable SMA/fatty acid composite PCMs had important potential for practical LHTES applications such as under floor space heating of buildings and passive solar space heating of buildings by using wallboard, plasterboard or floors impregnated with a form stable PCM due to their satisfying thermal properties, easy preparation in desired dimensions, direct usability without needing additional encapsulation thereby eliminating the thermal resistance caused by the shell and, thus, reducing the cost of

  5. Safety evaluation of long-term vas occlusion with styrene maleic anhydride and its non-invasive reversal on accessory reproductive organs in langurs

    Institute of Scientific and Technical Information of China (English)

    B. Manivannan; S. S. Bhande; S. Panneerdoss; S. Sriram; N. K. Lohiya

    2005-01-01

    Aim: To evaluate the safety of the long term vas occlusion with styrene maleic anhydride (SMA) and its non-invasive reversal at the level of accessory reproductive glands (ARGs) in langurs. Methods: The morphology of seminal vesicle and ventral prostate was evaluated by light as well as transmission electron microscopy. Serum clinical chemistry and urine albumin were evaluated in an autoanalyzer using reagent kits. Fructose, acid phosphatase and zinc in the seminal plasma were evaluated spectrophotomet-ically according to the WHO manual. Serum testosterone,prostate specific antigen and sperm antibodies were evaluated by enzyme-linked immunosorbent assays (ELISA)using reagent kits and hematology was estimated according to standard procedures. Results: The morphological features and secretory activity of the seminal vesicle and prostate were normal as evidenced by the presence of welldeveloped mitochondria, rough endoplasmic reticulum, Golgi bodies, secretory granules and normal nuclear characteristics throughout the course of investigation. Serum testosterone and prostate specific antigen remained unaltered and serum antisperm antibodies level presented negative titres. Urine albumin was nil. Total red blood corpuscles (RBC), white blood corpuscles (WBC), hemoglobin (Hb) and red cell indices, serum protein, glucose, cholesterol,creatinine, creatine kinase (CK), serum glutamate oxalate transaminase (SGOT), serum glutamate pyruvate transaminase (SGPT), lactate dehydrogenase (LDH), bilirubin, urea, triglycerides and high-density lipoprotein (HDL) did not show appreciable changes following vas occlusion and after its non-invasive reversal. Although fructose, acid phosphatase (ACP) and zinc in the seminal plasma showed a significant reduction following vas occlusion, it could not be related to the morphology of seminal vesicle and prostate. Conclusion: SMA vas occlusion and its non-invasive reversal do not damage the accessory reproductive organs.

  6. Isothermal Vapor-liquid Equilibria for the Binary System Maleic Anhydride+Di-n-butylsebacate%顺丁烯二酸酐-癸二酸二丁酯二元体系等温气液平衡

    Institute of Scientific and Technical Information of China (English)

    朱荣娇; 刘淑参; 季甲; 田宜灵

    2009-01-01

    Vapor-liquid equilibrium(VLE) data for maleic anhydride (MAN) and its absorption solvents are important for developing and researching the MAN production process. Isothermal VLE data for MAN and di-n-butylsebacate(DBS) binary system at 413.15, 433.15 and 453.15 K were determined with a modified ebulliometer in this work. Saturated pressure of pure DBS and MAN were measured and their Antoine constants were obtained. The experimental results were correlated and calculated using the NRTL model. The UNIFAC model was also used to predict the VLE data. At the same time, the parameters of the NRTL model for the MAN(l) +DBS(2) binary system were obtained. And the predicted results show a good agreement between the correlated data and the experimental data.%利用改进的沸点仪测定了顺酐-癸二酸二丁酯二元体系在413.15, 433.15和453.15 K下的等温气液平衡数据以及纯癸二酸二丁酯和顺酐的饱和蒸气压数据. 通过与文献值对比, 验证了此方法的可靠性. 同时, 将实验数据回归得到了纯癸二酸二丁酯和顺酐的Antoine常数. 利用NRTL方程进行了气液平衡数据的关联推算, 得到了顺酐-癸二酸二丁酯二元体系的NRTL模型参数. 利用UNIFAC基团贡献法对实验数据进行了预测, 其结果与实验值及运用NRTL方程拟合的结果吻合较好.

  7. Solid—Liquid Equilibria of Several Binary and Ternary Systems Containing Meleic Anhydride

    Institute of Scientific and Technical Information of China (English)

    MAPeisheng; CHENMingming; 等

    2002-01-01

    Solid-liquid equilibria(SLE) of three binary systems and seven ternary systems containing maleic anhydride(MA) are measured by visual method. The experimental data are compared with the calculated ones with modified universal quasichemical functional group activity coefficient(UNIFAC) method in which the interaction parameters between groups come from two sources,dortmund data bank (DDB), if there′s any,and correlations based on our former presented experimental SLE data of twenty binary systems.New groups of MA,ACCOO group,COO group,>C=O group and cy-CH2 group are defined and the SLE data of maleic anhydride in isopropyl acetate in literature are cited in order to assess the new interaction parameters,correlated with Wilson equation and the λh equation.The modified UNIFAC method with these new regressed interaction parameters is also used to predict other three binary systems containing maleic anhydride.

  8. TiOx(x<2)表面修饰Ni/TiO2-SiO2催化顺酐液相选择加氢合成γ-丁内酯%Selective Hydrogenation of Maleic Anhydride to γ-Butyrolactone over TiOx (x < 2) Surface-Modified Ni/TiO2-SiO2 in Liquid Phase

    Institute of Scientific and Technical Information of China (English)

    杨燕萍; 张因; 高春光; 赵永祥

    2011-01-01

    TiO2-SiO2 aerogel with different TiO2 content was prepared by the sol-gel method. Ni/TiCh-SiCh catalyst samples were then pre pared via impregnation and were applied to the selective hydrogenation of maleic anhydride (MA) to y-butyrolactone (GBL). The catalyst samples were characterized by infrared spectroscopy, N2 adsorption-desorption, temperature-programmed reduction, X-ray diffraction, dif fuse reflectance infrared Fourier transform spectroscopy, and H2 temperature-programmed adsorption-mass spectroscopy techniques. The characterization results indicated that smaller Ni° species favored the formation of GBL. Meanwhile, TiOx (x < 2) species, produced by the partial reduction of TiO2, was generated during the reduction process. The formation of TiOx (x < 2) species effectively promoted the hydro genation of C=O group. Therefore, the hydrogenation of carbonyl was affected by both the size of Ni0 and TiOx species. When the synergistic effect of small Ni0 and TiOx species existed, the catalyst showed higher hydrogenation activity for C=O group.%以TiO2-SiO2复合氧化物气凝胶为载体,制备了一系列Ni/TiO2-SiO2催化剂,并采用N2物理吸附-脱附、H2程序升温还原/脱附、X射线衍射及原位漫反射傅里叶变换红外光谱等技术对催化剂进行了表征,考察了载体中钛含量对催化剂结构、表面性质及其催化顺酐液相选择加氢合成γ-丁内酯反应性能的影响.结果表明,较小的Ni0晶粒有利于γ-丁内酯的生成.在催化剂活性组分的还原过程中,随着载体中钛含量的增加,越米越多的TiO2被还原为TiOx(x<2)物种.Ni0晶粒和TiOx物种的协同作用影响了催化剂的羰基加氢性能;当较小的Ni0晶粒匹配合适的TiOx物种时,催化剂表现出较高的羰基加氢活性.

  9. Research progress of maleic anhydride grafted polyethylene for hot melt adhesive%热熔胶用马来酸酐接枝聚乙烯研究进展

    Institute of Scientific and Technical Information of China (English)

    李文; 张华华; 闫瑞涛; 周文娟; 陈艳军; 张超灿

    2016-01-01

    Maleic anhydride grafted polyethylene is widely used as hot melt adhesive in steel-plastic composite pipe,because of its excellent adhesive properties,and low cost. The grafted progress is always processed through twin-screw extrude. In this paper,the effect of reaction conditions on the graft reaction are summarized,such as initiation methods,reaction temperature,screw structure and speed. The influence of initiators,PE type,and modified monomers are also concluded. Then,the characterization methods of the grafting yield are summarized,such as chemical titration and infrared spectroscopy. The effects of surface treatment and coating process on the peeling strength are discussed too. Finally,we pointed out some drawbacks of traditional sample preparing methods in peeling strength and put forward a reliable way to obtain stable and reliable peeling strength data. The research prospects of PE hot melt adhesive of low maleic anhydride content,excellent adhesion property and environmental characteristics,are predicated.%通过双螺杆挤出机将马来酸酐熔融接枝聚乙烯,制备的聚乙烯热熔胶具有粘接性能强、价格低等优点,广泛地应用于钢塑复合管。本文根据近年来聚乙烯热熔胶的研究方向,综述了新型引发剂及引发方式对接枝反应的影响;比较了不同种类聚乙烯接枝效果的差异;总结了改性单体对热熔胶性能的改善以及温度、挤出机螺杆结构和转速等工艺条件对聚乙烯热熔胶的影响。分别总结了化学滴定法和红外光谱法对接枝率的表征;简述了材料表面处理和涂胶工艺对剥离强度的影响。分析了热熔胶剥离强度传统制样方法的不足,并总结了能得到稳定真实剥离强度的制样方案。展望了低马来酸酐含量、高粘接强度的绿色环保型聚乙烯热熔胶的研究前景。

  10. [Studies on the characters and microstructure of enzyme and octenyl succinic anhydride modified starch].

    Science.gov (United States)

    Zhang, Xue-chun; Zheng, Wei-wan; Tu, Zong-cai; Lin, Hong-hui; Wang, Zhen-xing; Kong, Ling-wei

    2010-11-01

    Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), UV-Vis spectra, laser nano size detector (LNSD) and scanning electron microscope (SEM) were employed to analyze the characters and structure of enzyme and octenyl succinic anhydride modified starch. The results indicated that the enzymatic starch reacted with octenyl succinic anhydride, bringing only octenyl succinic anhydride groups but not any other groups. The esterification of enzymatic starch only took place in amorphous region, but had no effect on the crystal form of starch granule. The clarity of EOSS increased with the increase in substitution degree. The particle size of oil emulsion made by EOSS was fine and well-distributed, meaning that the emulsion has excellent emulsibility and emulsifying stability. The embedding of oil encapsulated with EOSS is fine. It can be concluded that the properties of EOSS is excellent, and can be used as emulsifier and wall material of microcapsule.

  11. Study on oil absorbency of succinic anhydride modified banana cellulose in ionic liquid.

    Science.gov (United States)

    Shang, Wenting; Sheng, Zhanwu; Shen, Yixiao; Ai, Binling; Zheng, Lili; Yang, Jingsong; Xu, Zhimin

    2016-05-05

    Banana cellulose contained number of hydrophilic hydroxyl groups which were succinylated to be hydrophobic groups with high oil affinity. Succinic anhydride was used to modify banana cellulose in 1-allyl-3-methylimidazolium chloride ionic liquid in this study. The modified banana cellulose had a high oil absorption capacity. The effects of reaction time, temperature, and molar ratio of succinic anhydride to anhydroglucose on the degree of substitution of modified banana cellulose were evaluated. The optimal reaction condition was at a ratio of succinic anhydride and anhydroglucose 6:1 (m:m), reaction time 60min and temperature 90°C. The maximum degree of acylation reaction reached to 0.37. The characterization analysis of the modified banana cellulose was performed using X-ray diffractometer, Fourier transform infrared spectrometer, scanning electron microscopy and thermogravimetry. The oil absorption capacity and kinetics of the modified banana cellulose were evaluated at the modified cellulose dose (0.025-0.3g), initial oil amount (5-30g), and temperature (15-35°C) conditions. The maximum oil absorption capacity was 32.12g/g at the condition of the cellulose dose (0.05g), initial oil amount (25g) and temperature (15°C). The kinetics of oil absorption of the cellulose followed a pseudo-second-order model. The results of this study demonstrated that the modified banana cellulose could be used as an efficient bio-sorbent for oil adsorption.

  12. Tannic Acid as a Bio-Based Modifier of Epoxy/Anhydride Thermosets

    Directory of Open Access Journals (Sweden)

    Xiaoma Fei

    2016-08-01

    Full Text Available Toughening an epoxy resin by bio-based modifiers without trade-offs in its modulus, mechanical strength, and other properties is still a big challenge. This paper presents an approach to modify epoxy resin with tannic acid (TA as a bio-based feedstock. Carboxylic acid-modified tannic acid (TA–COOH was first prepared through a simple esterification between TA and methylhexahydrophthalic anhydride, and then used as a modifier for the epoxy/anhydride curing system. Owing to the chemical modification, TA–COOH could easily disperse in epoxy resin and showed adequate interface interaction between TA–COOH and epoxy matrix, in avoid of phase separation. The use of TA–COOH in different proportions as modifier of epoxy/anhydride thermosets was studied. The results showed that TA–COOH could significantly improve the toughness with a great increase in impact strength under a low loading amount. Moreover, the addition of TA–COOH also simultaneously improved the tensile strength, elongation at break and glass transition temperature. The toughening and reinforcing mechanism was studied by scanning electron microscopy (SEM, dynamic mechanical analysis (DMA and thermal mechanical analysis (TMA, which should be owned to the synergistic effect of good interface interaction, aromatic structure, decreasing of cross linking density and increasing of free volume. This approach allows us to utilize the renewable tannic acid as an effective modifier for epoxy resin with good mechanical and thermal properties.

  13. 低温等离子体与马来酸酐对 UHMWPE 纤维表面改性%Low Temperature Plasma/Grafting Treatment of Maleic Anhydride on UHMWPE

    Institute of Scientific and Technical Information of China (English)

    赵艳凝; 赵丹丹; 侯金国; 王春莲

    2014-01-01

    Low temperature plasma technology and grafting treatment were used on surface modification on the ultra high molecular weight polyethylene fiber ( UHMWPE) surface.The optimum process of the grafted Maleic anhydride on the fiber surface was aqueous solution as a solvent and 1.0 mol/L of Maleic anhydride concentration at 80 ℃for 1.5 h.After the treated polar groups were grafted in the side chain of the fiber , so the chemical bonding ability with other matrix materials increased and the occlusion ability between the fiber surface and other materials enhanced but the mechanical properties and surface morphology of the fiber were kept unchanged.As a result, the surface properties were improved.%用低温等离子体技术和接枝反应对超高分子量聚乙烯( UHMWPE)纤维进行表面处理.纤维进行低温等离子体后接枝处理的最佳工艺条件是:在80℃的1.0 mol/L的马来酸酐水溶液中加热1.5 h在维持整体形貌的前提下,在纤维长链表面引入了活性基团,增大了纤维与其他基质材料之间的化学键合能力和咬合能力,提高纤维的表面性能,从而达到表面改性的目的。

  14. Position of modifying groups on starch chains of octenylsuccinic anhydride-modified waxy maize starch.

    Science.gov (United States)

    Bai, Yanjie; Kaufman, Rhett C; Wilson, Jeff D; Shi, Yong-Cheng

    2014-06-15

    Octenylsuccinic anhydride (OSA)-modified starches with a low (0.018) and high (0.092) degree of substitution (DS) were prepared from granular native waxy maize starch in aqueous slurry. The position of OS substituents along the starch chains was investigated by enzyme hydrolysis followed by chromatographic analysis. Native starch and two OS starches with a low and high DS had β-limit values of 55.9%, 52.8%, and 34.4%, respectively. The weight-average molecular weight of the β-limit dextrin from the OS starch with a low DS was close to that of the β-limit dextrin from native starch but lower than that of the β-limit dextrin from the OS starch with a high DS. Debranching of OS starches was incomplete compared with native starch. OS groups in the OS starch with a low DS were located on the repeat units near the branching points, whereas the OS substituents in the OS starch with a high DS occurred both near the branching points and the non-reducing ends.

  15. SMA-SH: Modified Styrene-Maleic Acid Copolymer for Functionalization of Lipid Nanodiscs.

    Science.gov (United States)

    Lindhoud, Simon; Carvalho, Vanessa; Pronk, Joachim W; Aubin-Tam, Marie-Eve

    2016-04-11

    Challenges in purification and subsequent functionalization of membrane proteins often complicate their biochemical and biophysical characterization. Purification of membrane proteins generally involves replacing the lipids surrounding the protein with detergent molecules, which can affect protein structure and function. Recently, it was shown that styrene-maleic acid copolymers (SMA) can dissolve integral membrane proteins from biological membranes into nanosized discs. Within these nanoparticles, proteins are embedded in a patch of their native lipid bilayer that is stabilized in solution by the amphipathic polymer that wraps the disc like a bracelet. This approach for detergent-free purification of membrane proteins has the potential to greatly simplify purification but does not facilitate conjugation of functional compounds to the membrane proteins. Often, such functionalization involves laborious preparation of protein variants and optimization of labeling procedures to ensure only minimal perturbation of the protein. Here, we present a strategy that circumvents several of these complications through modifying SMA by grafting the polymer with cysteamine. The reaction results in SMA that has solvent-exposed sulfhydrils (SMA-SH) and allows tuning of the coverage with SH groups. Size exclusion chromatography, dynamic light scattering, and transmission electron microscopy demonstrate that SMA-SH dissolves lipid bilayer membranes into lipid nanodiscs, just like SMA. In addition, we demonstrate that, just like SMA, SMA-SH solubilizes proteoliposomes into protein-loaded nanodiscs. We covalently modify SMA-SH-lipid nanodiscs using thiol-reactive derivatives of Alexa Fluor 488 and biotin. Thus, SMA-SH promises to simultaneously tackle challenges in purification and functionalization of membrane proteins.

  16. Effects of concentration of maleic anhydride of compatibilizer on morphology and mechanical properties of PA6/AES blend-based nanocomposites; Efeito da concentracao do grupo anidrido maleico do compatibilizante na morfologia e propriedades mecanicas de nanocompositos de blendas PA6/AES

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, A.D. de; Castro, L.D.C.; Jung, M.K.; Pessan, L.A., E-mail: amandaoliveira82@gmail.com [Universidade Federal de Sao Carlos (UFSCar), SP (Brazil)

    2014-07-01

    The effects of functionality and concentration of the maleic anhydride (MA) group of the copolymer methyl methacrylate-maleic anhydride (MMA-MA) on the morphology and mechanical properties of nanocomposites based on polyamide 6 (PA6)/acrylonitrile-EPDM-styrene (AES) were studied. The nanocomposites were prepared in a twin screw extruder and characterized by transmission electron microscopy (MET), wide angle X-ray diffraction (WAXD) and tensile and impact tests. The impact strength results showed that the addition of 5wt% of MMA-MA with 1.4wt% of MA is sufficient to increase the toughness of the nanocomposites. A significant increase of elastic modulus was observed for the nanocomposites with respect to the pure blend (PA6/AES). TEM micrographs showed that the clay layers exhibited exfoliated structure and are preferably located in the matrix phase. (author)

  17. Graft Modification of Cellulose with Maleic Anhydride by In-Situ Reactive Extrusion%反应挤出原位制备纤维素马来酸酯

    Institute of Scientific and Technical Information of China (English)

    张玥; 李海峰; 李欣达; 黎欢; 余木火

    2013-01-01

    以离子液体1-丁基-3-甲基咪唑氯盐([Bmim] Cl)作反应介质,采用马来酸酐对纤维素进行原位化学改性.利用双螺杆挤出机的剪切作用来提高纤维素在[Bmim] Cl中的溶解效率,并促进马来酸酐与纤维素的醣化反应.红外光谱(FTIR)结果证明了纤维素马来酸酯的生成,导致纤维素的氢键网络结构破坏,同时也破坏了纤维素的规整度,降低了纤维素的结晶度.热重分析(TGA)结果显示:马来酸酐支链阻碍了纤维素主链的运动,使改性纤维素的热稳定性明显高于未改性纤维素.当马采酸酐与纤维素质量比为0.8、螺杆转速为50 r/min时,改性纤维素在[Bmim]Cl中的溶解度达到20%,是未改性纤维素溶解度的2倍.%Cellulose is chemically modified with maleic anhydride(MA) by in-situ reactive extrusion.1-N-butyl-3-methylimidazolium chloride ([Bmim]Cl) is applied as reaction medium.Owing to the high shear stress of twin-screw extruder,the dissolving efficiency of cellulose in [Bmim]Cl as well as the modification effect of MA is improved effectively.Fourier transform infrared spectrscope (FTIR) results show that the formation of MA side chain in cellulose maleate obviously destroys the regularity of cellulose chains and reduces the crystallinity of cellulose.Thermal gravimetric analysis(TGA) results show that the resistance of cellulose segment motion in the cellulose maleate suppresses the degradation of cellulose in [Bmim]Cl and improves the thermal stability of cellulose maleate.The hydrogen bond network in cellulose maleate is destructed efficiently and intermolecular force of cellulose maleate is decreased with the increase of MA content.As a result,the concentration of cellulose in spinning solution can be up to 20 % when the MA content is 80 % with respect to the weight of cellulose and the screw speed is 50 rpm,which is almost double of the concentration of unmodified cellulose.

  18. SMA共聚物玻璃化转变温度测定条件的优化%Optimal Analytical Procedure for Measuring Glass Transition Temperature of Styrene-Maleic Anhydride Copolymer

    Institute of Scientific and Technical Information of China (English)

    蒙根; 许中强; 朱海燕

    2012-01-01

    Styrene-maleic anhydride (SMA) copolymer is a commercially heat resistant materials and compatibilizer bearing reactive anhydride groups.The effects of atmosphere,heating rate,sample mass and flow rate of carrier gas on glass transition temperature of SMA were also investigated by differential scanning calorimetry (DSC) N2 is preferred as the carrier gas.Moderate carrier gas flow rate,heating rate and sample mass help to obtain relatively accurate results.The results indicate that Ts of SMA was measured preferably with the sample mass of about 10 mg,N2 flow rate of 40 mL/min and heating rate of 20 ℃/min,which is proved appropriate by dynamic mechanical thermal analysis.%利用差示扫描量热法(DSC)研究了气氛、升温速率、试样量和载气流速对苯乙烯-马来酸酐共聚物(SMA)玻璃化转变温度的影响.并用优化后的条件考察了上海石油化工研究院自制SMA样品的玻璃化转变温度.实验结果表明,在试样量10mg左右、氮气流速40 mL/min、升温速率20℃/min的优化条件下,测定结果良好.经验证,DSC与动态机械热分析(DMTA)所测得的Tg基本一致,表明优化后的条件很适合SMA玻璃化转变温度的测定,此结果有助于SMA的生产和应用.

  19. Study on thermal properties and crystallization behavior of electron beam irradiated ethylene vinyl acetate (EVA)/waste tyre dust (WTD) blends in the presence of polyethylene graft maleic anhydride (PEgMAH)

    Science.gov (United States)

    Ramli, Syuhada; Ratnam, C. T.; Ahmad, S. H.; Athirah, Nurul

    2013-11-01

    The aim of this article is to show the effects of the electron beam irradiation dose and presence of a compatibiliser on the thermal properties and crystallinity of EVA/WTD blends. The purpose of applying electron beam radiation with doses range 50 to 200 kGy and adding a compatibiliser was to enhance the compatibility of the studied blends and at the same time to investigate the possibility of using this technique in the process of recycling polymeric materials. As the compatibilisers, the polyethylene grafted maleic anhydride (PEgMAH) was utilized, they were added at the amounts of 1-5 phr respectively. The enhancement of thermal properties was accompanied by the following effects, discussed in this article: i) an irradiated EVA/WTD blend at 200kGy was found to improve the thermal properties of EVA, ii) the addition of PEgMAH in EVA/WTD blends and the subsequent irradiation allowed prevention of degradation mechanism. iii) the ΔHf and crystallinity percentage decrease at higher PEgMAH content.

  20. Preparation and Characterization of Octenyl Succinic Anhydride Modified Taro Starch Nanoparticles.

    Science.gov (United States)

    Jiang, Suisui; Dai, Lei; Qin, Yang; Xiong, Liu; Sun, Qingjie

    2016-01-01

    The polar surface and hydrophilicity of starch nanoparticles (SNPs) result in their poor dispersibility in nonpolar solvent and poor compatibility with hydrophobic polymers, which limited the application in hydrophobic system. To improve their hydrophobicity, SNPs prepared through self-assembly of short chain amylose debranched from cooked taro starch, were modified by octenyl succinic anhydride (OSA). Size via dynamic light scattering of OSA-SNPs increased compared with SNPs. Fourier transform infrared spectroscopy data indicated the OSA-SNPs had a new absorption peak at 1727 cm-1, which was the characteristic peak of carbonyl, indicating the formation of the ester bond. The dispersibility of the modified SNPs in the mixture of water with nonpolar solvent increased with increasing of degree of substitution (DS). OSA-SNPs appear to be a potential agent to stabilize the oil-water systems.

  1. Preparation, characterization and antibacterial activity of octenyl succinic anhydride modified inulin.

    Science.gov (United States)

    Zhang, Xiaoyun; Zhang, Ye-Wang; Zhang, Hongyin; Yang, Qiya; Wang, Haiying; Zhang, Guochao

    2015-01-01

    Octenyl succinic anhydride modified inulin (In-OSA) was synthesized via chemical modification of inulin with octenyl succinic anhydride (OSA). The esterification of inulin with OSA was confirmed by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and degree of substitution (DS) calculation. Antibacterial activity of In-OSA against Staphylococcus aureus and Escherichia coli was investigated by minimum inhibitory concentration (MIC) and inhibition rate determination. The results showed that inhibition rates against both E.coli and S. aureus increased with the increase of the In-OSA concentration. And the MICs against E. coli and S. aureus were 1% and 0.5% (w/v), respectively. The antibacterial mechanism was analyzed with the results of the proteins and nucleic acids leakage, SEM and negative staining transmission electron microscopy (TEM). Both the leakages of proteins and nucleic acids increased with the increase of the In-OSA concentration. The leakage occurred mainly in the early stage which indicated that cell membrane and wall were destroyed by In-OSA quickly. The images of SEM and negative staining TEM suggested that the cell membranes and cell walls of S. aureus were damaged more severely and even destroyed completely; but only pores appeared on the surface of E. coli.

  2. Synthesis and paste properties of octenyl succinic anhydride modified early Indica rice starch

    Institute of Scientific and Technical Information of China (English)

    SONG Xiao-yan; CHEN Qi-he; RUAN Hui; HE Guo-qing; XU Qiong

    2006-01-01

    Octenyl succinic anhydride (OSA) modified early Indica rice starch was prepared in aqueous slurry systems using response surface methodology. The paste properties of the OSA starch were also investigated. Results indicated that the suitable parameters for the preparation of OSA starch from early Indica rice starch were as follows: reaction period 4 h, reaction temperature 33.4 ℃, pH of reaction system 8.4, concentration of starch slurry 36.8% (in proportion to water, w/w), amount of OSA 3% (in proportion to starch, w/w). The degree of substitution was 0.0188 and the reaction efficiency was 81.0%. The results of paste properties showed that with increased OSA modification, the starch derivatives had higher paste clarity, decreased retrogradation and better freeze-thaw stability.

  3. Preparation and structural characterisation of novel and versatile amphiphilic octenyl succinic anhydride-modified hyaluronic acid derivatives

    DEFF Research Database (Denmark)

    Eenschooten, Corinne Diane; Guillaumie, Fanny; Kontogeorgis, Georgios

    2010-01-01

    The purpose of the present study was to prepare amphiphilic hyaluronic acid (HA) derivatives and to study the influence of a selection of reaction parameters on the degree of substitution (DS) of the derivatives. Octenyl succinic anhydride (OSA)–modified HA (OSA–HA) derivatives were prepared...

  4. 马来酸酐及其酯接枝mPE增容PA 6/mPE共混物的制备%Properties of PA 6/metallocene PE blends compatibilized by maleic anhydride and dibutyl maleate grafted metallocene PE

    Institute of Scientific and Technical Information of China (English)

    赵连国; 张良均

    2012-01-01

    The author prepared maleic anhydride grafted metallocene polyethylene (Mpe) (Mpe-g-MAH) and dibutyl maleate grafted Mpe (Mpe-g-DBM) via aqueous suspension grafting. The grafted products were taken as compatibilizers of polyamide (PA) 6/Mpe and were applied to the preparation of ternary blends, such as polyamide(PA) 6/Mpe/Mpe-g-M A H or PA 6/Mpe/Mpe-g-DBM. The compatibility between PA 6 and Mpe in the ternary blends was greatly strengthened with increasing the amount of Mpe-g-MAH or Mpe-g-DBM, which led to a rise in y crystal and a reduction in a crystal of PA 6 in the blends. As a result, the toughness, especially the low temperature toughness of the ternary blends was improved. The compatibilizing and toughening efficiency of Mpe-g-DBM were inferior to those of Mpe-g-MAH in the ternary blends for the reason that the anhydride groups of the latter were easier to react with the amino or imino groups of PA 6 in comparison with the ester groups of the former, although Mpe-g-DBM had higher grafting ratio than Mpe-g-MAH did.%采用水相悬浮法制备了马来酸酐接枝茂金属聚乙烯(mPE-g-MAH)、马来酸二丁酯接枝茂金属聚乙烯(mPE-g-DBM),并以其为聚酰胺(PA)6/茂金属聚乙烯(mPE)共混物的增容剂,分别制备了PA 6/mPE/mPE-g-MAH,PA 6/mPE/mPE-g-DBM 三元共混物.随着mPE-g-MAH,mPE-g-DBM用量的增加,三元共混物中PA 6的γ晶型增多,α晶型减少,PA 6与rmPE的相容性加强,使三元共混物的韧性,特别是低温韧性提高.尽管mPE-g-DBM的接枝率比mPE-g-MAH高,但由于后者中的酸酐基团比前者的酯基更易与PA 6中的氨基、亚氨基反应,因此,mPE-g-DBM的增容、增韧效果不如mPE-g-MAH.

  5. Dimethylmaleic anhydride, a specific reagent for protein amino groups.

    Science.gov (United States)

    de la Escalera, S; Palacián, E

    1989-01-01

    The reagent dimethylmaleic anhydride does not cause a stable modification of thiol compounds under the conditions used for modification of protein amino groups, in contrast to maleic and monomethylmaleic anhydrides, which produce an irreversible modification of sulfhydryl groups. This behavior and the low reactivity toward hydroxyamino acid residues, shown in a previous work, make dimethylmaleic anhydride a specific reagent for protein amino groups.

  6. 桐马酸酐与环氧树脂的非等温固化反应动力学%Non - isothermal curing kinetics of Tung - maleic anhydride and epoxy resin

    Institute of Scientific and Technical Information of China (English)

    黄坤; 夏建陵; 李梅; 林贵福; 连建伟

    2011-01-01

    The non- isothermal curing kinetics of Tung- maleic anhydride and epoxy resin E-51 blend with 1%DMP -30 by weight was studied by Má1ek method. The real curing process was stimulated well using mechanism equation (S)esták - Berggren. The active energy calculated by iso - conversion ratio method was 69. 78 kJ/mol. The pre -exponential factor A was 4. 567 × 108 min -1 and the values of n and m were 1. 082 and O. 456, respectively.Based on the curing kinetic equation obtained, the calculated curing time of the system with 98% conversion rate was 115 minutes at the curing temperature 137. 05 ℃.%采用Málek法对桐马酸酐与双酚A环氧树脂E-51体系(含有1%质最分数的DMP-30)的非等温固化反应动力学进行了研究.通过机理函数(S)esták-Berggren方程很好地模拟了真实的固化反应过程.等转化率法求得反应活化能为69.78 kJ/mol.指前因子A的值为4.567×108min-1,n和m的值分别为1.082和0.456.根据得到的同化动力学方程计算可知,在固化温度为137.05℃时达到98%固化度的固化时间为115 min.

  7. Studies on the rheological,phase morphologic,thermal and mechanical properties of poly(trimethylene terephthalate)/ethylene propylene diene monomer copolymer grafted with maleic anhydride/metallocene polyethylene blends

    Institute of Scientific and Technical Information of China (English)

    RUN Mingtao; SONG Hongzan; WANG Yingjin; YAO Chenguang; GAO Jungang

    2007-01-01

    s The rheological,phase morphologic,thermal and mechanical properties of poly(trimethylene terephthalate)/metallocene polyethylene(PTT/mPE)blends in the presence of ethylene propylene diene monomer copolymer grafted with maleic anhydride(EPDM-g-MAHl as compatibilizer are studied by means of a capillary rheometer,scanning electron microscopy(SEM),differential scanning calorimetry (DSC)and thermogravimetric analyzer (TGA).Results suggest that the compatibility of PTT/mPE blends is improved greatly after the addition of a compatibilizer.The radius of the dispersed phase in the system decreases greatly when the compatibilizer is added into the blend.When the amount of compatibilizer exceeds 8 wt-%,the size of dispersed phase becomes larger again.This phenomena could be attributed to the higher viscosity of the EPDM-g-MAH phase,which is dispersed more difficulty in the PTT phase of lower viscosity,thus the mixing efficiency is apparently decreased during the melt blending process.Moreover,the melt viscosity of the blend reaches the maximal value in case of 4 wt-%compatibilizer content,above which it would decrease again.This result is associated with the generation of more and bigger dispersed phase inside the bulk phase,thus the grafting efficiency at the interface is decreased,which could result in lower viscosity.The DSC results suggest that the mPE component shows a nucleating effect,and could increase the overall degree and rate of PTT crystallization,while the addition of a compatibilizer might slightly diminish these effects.In addition,the blend with 4 wt-% compatibilizer shows the best thermal stability.Furthermore,the Izod impact strength and the tensile strength at room temperature of the blend are also markedly improved by the addition of a 4-8 wt-% compatibilizer.

  8. Application of Maleic Anhydride/1-Decene Copolymer in Polypropylene Wood Plastic Composite%马来酸酐/1-十烯共聚物在聚丙烯木塑复合材料中的应用

    Institute of Scientific and Technical Information of China (English)

    徐运祺; 雷影红; 徐睿杰

    2012-01-01

    Maleic anhydride(MAH)/1-decene copolymer was synthesized and characterized by FTIR, 'H-NMR and GPC. The application of this copolymer as compatibilizer in polypropylene(PP) wood plastic composite was discussed. The results show that MAH/1-decenc copolymer can improve the dispersion of wood flour and the compatibility between wood flour and PP, enhance the interracial adhesion of wood plastic composite; when the compatibilizer content is 5 phr, the tensile strength, flexural strength and impact strength of the composite increase by 59.3%, 44.6% and 82.6% respectively.%采用红外光谱、核磁共振氢谱和凝胶渗透色谱表征了自行合成的马来酸酐(MAH)/1-十烯共聚物,探讨了该共聚物作为相容剂在聚丙烯(PP)基木塑复合材料中的应用.结果表明:MAH/1-十烯共聚物可改善木粉在PP中的分散性和相容性,提高PP与木粉间的界面黏合力,进而改善复合材料的力学性能;当相容荆用量为5份时,复合材料的拉伸强度提高了59.3%,弯曲强度提高了44.6%,冲击强度提高了82.6%.

  9. Collagen functionalized with unsaturated cyclic anhydrides-interactions in solution and solid state.

    Science.gov (United States)

    Potorac, S; Popa, M; Picton, L; Dulong, V; Verestiuc, L; Le Cerf, D

    2014-03-01

    Maleic anhydride (CMA) and itaconic anhydride modified collagen (CITA) were prepared as precursors for production of interpenetrated polymer networks (IPN). Calculated values for Huggins coefficient in aqueous diluted and semi-diluted solutions of modified collagen indicated a slightly tendency of aggregation for itaconic anhydride-modified collagen. In semi-diluted solution collagen (Coll) and CMA present slightly differences in the thixotropic behavior, while CITA has a pronounced thixotropic behavior. Flow and oscillatory measurements revealed an elastic behavior of the collagen solutions, pure and modified with MA or ITA, as the storage modulus (G') has always a superior value compared with the loss modulus (G″). The denaturation temperature (Td) of unmodified collagen increased from 34°C to 40°C for CMA and to 39°C for CITA respectively, by formation of covalent bonds that stabilize the triple helix.

  10. Multivalent host-guest interactions between ss-cyclodextrin self-assembled monolayers and poly (isobutene-alt-maleic acid)s modified with hydrophobic guest moeties

    NARCIS (Netherlands)

    Crespo biel, O.; Péter, M.; Bruinink, C.M.; Ravoo, B.J.; Reinhoudt, David; Huskens, Jurriaan

    2005-01-01

    Poly(isobutene-alt-maleic acid)s modified with p-tert-butylphenyl or adamantyl groups interact with ß-cyclodextrin self-assembled monolayers (ß-CD SAMs) by inclusion of the hydrophobic substituents in the B-cyclodextrin cavities. The adsorption was shown to be strong, specific, and irreversible.

  11. Elucidation of substituted ester group position in octenylsuccinic anhydride modified sugary maize soluble starch.

    Science.gov (United States)

    Ye, Fan; Miao, Ming; Huang, Chao; Lu, Keyu; Jiang, Bo; Zhang, Tao

    2014-12-01

    The octenylsuccinic groups in esterification-modified sugary maize soluble starches with a low (0.0191) or high (0.0504) degree of substitution (DS) were investigated by amyloglucosidase hydrolysis followed by a combination of chemical and physical analysis. The results showed the zeta-potential remained at approximately the same value regardless of excessive hydrolysis. The weight-average molecular weight decreased rapidly and reached 1.22 × 10(7) and 1.60 × 10(7) g/mol after 120 min for low-DS and high-DS octenylsuccinic anhydride (OSA) modified starch, respectively. The pattern of z-average radius of gyration as well as particle size change was similar to that of Mw, and z-average radius of gyration decreased much more slowly, especially for high-DS OSA starch. Compared to native starch, two characteristic absorption peaks at 1726.76 and 1571.83 cm(-1) were observed in FT-IR spectra, and the intensity of absorption peaks increased with increasing DS. The NMR results showed that OSA starch had several additional peaks at 0.8-3.0 ppm and a shoulder at 5.56 ppm for OSA substituents, which were grafted at O-2 and O-3 positions in soluble starch. The even distribution of OSA groups in the center area of soluble starch particle has been directly shown under CLSM. Most substitutions were located near branching points of soluble starch particles for a low-DS modified starch, whereas the substituted ester groups were located near branching points as well as at the nonreducing ends in OSA starch with a high DS.

  12. Gelatinization and pasting properties of rice starch modified with 2-octen-1-ylsuccinic anhydride.

    Science.gov (United States)

    Shih, Fred F; Daigle, Kim W

    2003-02-01

    Rice starch was modified with various levels of 2-octen-1-ylsuccinic anhydride (OSA). Treatments with OSA at 3, 5, and 10% resulted in starch derivatives with 0.016, 0.033, and 0.070 degrees of substitution (DS), respectively. Thermovisco properties of the derivatives were investigated by differential scanning calorimetry (DSC) and rapid visco analysis (RVA). Water content in the sample was found to have a significant effect on the characteristics of the DSC endotherm. Pasting properties of the OSA-starch and the effect of pH and salt on the RVA profiles were also studied. In general, with increased OSA-modification, the starch derivatives swelled and gelatinized at lower temperatures to achieve higher viscosities. Specifically, based on DSC analysis at 80% water, the peak temperature of gelatinization decreased from 68.5 to 63.2 degrees C as the OSA modification increased in DS from 0 (intact starch) to 0.070. On the other hand, RVA results indicate that, for samples undergoing similar increase in OSA modification, the pasting temperature decreased from 88.7 to 51.5 degrees C and the peak viscosity increased from 668 to 6822 cP.

  13. Preparation and Application of Novel Maleic Anhydride Grafted Propylene-based Elastomer%新型马来酸酐接枝丙烯基弹性体的制备及其应用研究

    Institute of Scientific and Technical Information of China (English)

    汤俊杰; 段浩; 杨涛; 郭建鹏; 孟成铭

    2011-01-01

    Maleic anhydride was grafted onto propylene-based elastomer via melt reaction in a twin-screw extruder. The influences of initiator, MAH concentration, crossli~king inhibitor, and processing condition on the structure and properties of the products were analyzed using FT-IR and neutralization titration. It indicated that with increasing initiator concentration the grafting degree increased first and then dropped. With increasing MAH concentration, the grafting degree increased first and then leveled off. The crosslinking during grafting was best inhibited by hexanolactam. The toughening effect of the products and traditional POE-g-MAH were compared in polyamide, and it was found that the grafted product achieved both better tougheness and flowability of polyamide.%通过熔融反应挤出制备了一种新型马来酸酐接枝丙烯基弹性体(以下简称接枝物),研究了引发剂用量、马来酸酐(MAH)用量、交联抑制剂的种类和加工工艺条件对接枝物性能的影响。利用红外光谱对接枝物进行了结构表征,并用酸碱滴定法测定其接枝率,同时比较了该接枝物与传统马来酸酐接枝乙烯-辛烯弹性体(MAH—g-POE)在聚酰胺(PA)中的增韧效果。结果表明,随着引发剂含量的增加,接枝物的接枝率先增大后下降;随着MAH含量的增加,其接枝率先增大后趋于平稳;己内酰胺对接枝物的交联副反应抑制效果最好;接枝物作为增容剂提高了PA的熔体流动速率,达到增韧效果。

  14. 氨基硅烷/马来酸酐接枝聚丙烯界面化学反应的研究%A Study of Interface Reaction between Amino Silane and Maleic Anhydride Grafted Polypropylene

    Institute of Scientific and Technical Information of China (English)

    余剑英; 周祖福; 赵青南; 程景飞; 闻荻江

    2000-01-01

    Through removing polymer physisorbed on the glass fiber surface with solvent extraction to minimize the signal of the polymer in IR and XPS analysis,the interaction was studied by IR and XPS between maleic anhydride grafted polypropylene(MA-g-PP)and an amino silane coupling agent-γ-aminopropyltrimethoxy silane(APS).It is found that the absorption bands of polypropylene still exits in IR spectra of the glass fiber after 72h dimethyl benzene extraction and a new state of N1s at 401.9eV appears in the XPS,which shows that the MA-g-PP and APS have reacted chemically and the reaction product with amido is formed.Although open chain APS and cyclic APS with an internal hydrogen bond coexist on the APS treated glass fiber surface,it is discovered that APS which reacts chemically with MA-g-PP is mainly open chain APS by the quantitative analysis of XPS for N1s in different chemical state.%利用溶剂萃取与红外光谱(IR)、光电子能谱(XPS)技术研究了化学键接在玻璃纤维表面的硅烷偶联剂与接枝聚丙烯间的界面化学反应。结果表明:溶剂萃取可以除去玻璃纤维/树脂界面区物理结合的聚合物基体,减少基体信号的影响,在此基础上,利用IR、XPS可以直接证明氨基硅烷(APS)与马来酸酐接枝聚丙烯(MA-g-PP)间发生了界面化学反应,生成了含酰胺基的反应产物。进一步对不同化学状态的N1s的XPS定量分析发现,尽管APS在玻纤表面以开环直链和以氢键结合的环状两种结构形式存在,但在界面上主要是无环开链结构中的氨基与酸酐发生反应。

  15. EPDM-g-MAH对PP膨胀阻燃材料性能的影响%Effect of maleic anhydride grafted EPDM on properties of intumescent flame retardant PP materials

    Institute of Scientific and Technical Information of China (English)

    闫怀文; 危加丽; 尹波; 杨鸣波

    2012-01-01

    采用氮磷膨胀型阻燃剂制备了无卤阻燃聚丙烯(PP)材料,研究了马来酸酐(MAH)接枝三元乙丙橡胶(EPDM)(EPDM-g-MAH)对PP无卤阻燃材料性能的影响.结果表明:加入EPDM-g-MAH可提高阻燃剂和PP基体间的界面作用,降低试样在燃烧过程中的熔融滴落现象,且加入EPDM-g-MAH提高了阻燃PP的力学性能.此外,加入EPDM-g-MAH可提高PP无卤阻燃材料在高温(600~800℃)下的炭层热稳定性以及材料的最大热分解速率,但会降低材料的最大热分解温度.因此,少量的EPDM-g-MAH可以提高PP无卤阻燃材料的极限氧指数(LOI),但当w(EPDM-g-MAH)超过10%时,PP无卤阻燃材料的LOI下降,阻燃性能降低.%The authors prepared halogen-free flame retardant polypropylene (PP) by introducing intumescent flame retardant made from nitrogen phosphorus compound, and studied the effect of content of maleic anhydride grafted ethylene propylene diene monomer(EPDM-g-MAH) on properties of the PP materials. The results show that adding EPDM-g-MAH can enhance interfacial interaction between PP matrix and the flame retardant, reduce melt dripping of the specimens during combustion process and improve mechanical properties of the PP materials. The addition of EPDM-g-MAH can raise thermal stability of the carbon layer at high temperature (600-800 ℃) and the maximum thermal decomposition rate but lowers the maximum thermal decomposition temperature of the PP materials. As a result, adding a small quantity of EPDM-g-MAH can make the limited oxygen index (LOF) of the PP materials augment However, the LOI decreases and the flame retardancy of the PP material declines when the mass content of EPDM-g-MAH exceeds 10%.

  16. 苯乙烯-马来酸酐共聚物对大庆原油降凝作用的研究%Pour-point depressing process of styrene-maleic anhydride copolymer in Daqing crude oil

    Institute of Scientific and Technical Information of China (English)

    郑彤; 孙寿家; 陈志强

    2000-01-01

    The effect of pour-point depressing and viscosity reducing to crude-oil which led by pour-point depressor would be severely influenced by the depressor' s molecular configuration, additive quantity, active temperature, and shearing strength. And it also relates to the quality of crude oil including cere concentration, pectin concentration, carbon amount distribution and composition. For producing a kind of depressor suitable to Daqing crude-oil, a pourpoint depressor (HJN-5 # ) mainly cousisting of an esterification product of styrene-maleic anhydride copolymer(SMA) has been prepared, and the relationships between the pour-poim depressing effect and the impacting factors including depressor concentration, activation temperature , and shear intensity have also been researched. In addition, by watching the variation of modality of cere crystalloid caused by adding depressor, the mechanism of pourpoint depressing and viscosity reducing were discussed. The results show that adding 0.2 wt% of HJN-5 # could get 50% depression of pour-point and more than 90% reduction of apparent viscosity of Daqing crude oil. The rnost suitable activation temperature of the depressor is 88 ℃.%降凝剂对原油的降凝减粘效果受其分子结构、使用剂量、活化温度及所受剪切强度的影响,并与原油的品质(如:蜡含量、胶质含量、碳数分布及组成等)有着密切的关系.为研制出适合大庆原油品质的降凝剂,合成了以苯乙烯-马来酸酐共聚物(SMA)的酯化物为主体的酯型降凝剂(HJN-5#),并对其使用剂量、活化温度等参数进行了研究,还根据观察到的降凝剂使用前后原油中蜡晶形态的变化对降凝减粘作用机理进行了讨论.结果表明,添加质量百分数为0.2%的HJN-5#,可使大庆原油的倾点下降50%,表观粘度下降90%以上,最佳活化温度为88℃

  17. Pomelo peel modified with acetic anhydride and styrene as new sorbents for removal of oil pollution.

    Science.gov (United States)

    Chai, Wenbo; Liu, Xiaoyan; Zou, Junchen; Zhang, Xinying; Li, Beibei; Yin, Tiantian

    2015-11-01

    Pomelo peel (PP), as one of the well-known agricultural wastes, is cost-effective and environmentally friendly. Based on PP, two new kinds of oil sorbents were prepared by using acetic anhydride and styrene. The structures of raw pomelo peel (RP), acetic anhydride-treated pomelo peel (AP) and styrene-treated pomelo peel (SP) were characterized by Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM), contact-angle (CA) measurements. The optimum reaction conditions for preparation of AP and SP were also investigated. The resulting products exhibited better oil sorption capacity than that of RP for diesel and lubricating oil, also SP had better oil sorption capacity than AP, while the oil sorption capacities of SP for diesel and lubricating oil reached 18.91 and 26.36 g/g, respectively. Adsorption kinetics was well described by the pseudo-second-order model. The results indicated that AP and SP, especially SP could be used as the substitute for non-biodegradable oil sorption materials.

  18. Ionic liquids as novel solvents for biosynthesis of octenyl succinic anhydride-modified waxy maize starch.

    Science.gov (United States)

    Li, Dandan; Zhang, Xiwen; Tian, Yaoqi

    2016-05-01

    Biosynthesis of octenyl succinic anhydride (OSA) starch was investigated using ionic liquids (ILs) as reaction media. Waxy maize starch was pretreated in 1-butyl-3-methylimidazolium chlorine and then esterified with OSA in 1-octyl-3-methylimidazolium nitrate by using Novozyme 435 as catalyst. The degree of substitution of OSA starch reached 0.0130 with 5 wt% starch concentration and 1 wt% lipase dosage based on ILs weight at 50 °C for 3h. The formation of OSA starch was confirmed by fourier transform infrared spectroscopy. Scanning electron microscopy and X-ray diffraction revealed that the morphology and crystal structure of starch were significantly destroyed. Thermogravimetric analysis showed that esterification decreased the thermal stability of starch. The successful lipase-catalyzed synthesis of OSA starch in ILs suggests that ILs are potential replacement of traditional organic solvents for starch ester biosynthesis.

  19. Application of palladium-catalyzed carboxyl anhydride-boronic acid cross coupling in the synthesis of novel bile acids analogs with modified side chains.

    Science.gov (United States)

    Mayorquín-Torres, Martha C; Flores-Álamo, Marcos; Iglesias-Arteaga, Martin A

    2015-09-01

    Palladium-catalyzed cross coupling of 4-methoxycarbonyl phenyboronic acid with acetylated bile acids in which the carboxyl functions was activated by formation of a mixed anhydride with pivalic anhydride afforded the cross coupled compounds, which were converted in novel side chain modified bile acids by one pot carbonyl reduction/removal of the protecting acetyl groups by Wolff-Kishner reduction. Unambiguous assignments of the NMR signals and crystal characterization of the heretofore unknown compounds are provided. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Cantharidin and its anhydride-modified derivatives: relation of structure to insecticidal activity.

    Science.gov (United States)

    Sun, Wenbo; Liu, Zhongyi; Zhang, Yalin

    2012-12-20

    Cantharidin is a natural compound of novel structure with ideal insecticidal activity. However, the relationship of structure to insecticidal activity of cantharidin and its derivatives has not been ever clarified. To explore what determines the insecticidal activity structurally of cantharidin-related compounds, two series target compounds 6 and 7 were synthesized by replacing the anhydride ring of norcantharidin with an aromatic amine or fatty amine with different electron density, respectively. The structures of these compounds were characterized by 1H NMR, 13C NMR and HRMS-ESI. A bioassay showed that compounds 6 (a-m) lacked any larvicidal activity against Plutella xylostella; whereas their ring-opened partners 7 (a-m) provided a variety of larvicidal activities against P. xylostella, and compound 7f indicated the highest larvicidal activity with LC(50) value of 0.43 mM. The present work demonstrated that the form of the compound (cyclic or ring-opened) or their ability to hydrolyze facilely was the key to determine whether it exhibits larvicidal activity. Moreover, it revealed that the improvement of insecticidal activity required a reasonable combination of both aliphatic amide and aromatic amide moieties, and the type of substituent Y on the aniline ring was critical.

  1. Rheological, pasting, thermal and retrogradation properties of octenyl succinic anhydride modified potato starch

    Directory of Open Access Journals (Sweden)

    Chuin WON

    Full Text Available Abstract The objective of the present study was to investigate the rheological, pasting, and thermal properties of octenyl succinic anhydrate (OSA-modified potato starch. Potato starch was modified using different concentrations of OSA (0, 1, 3, and 5%, v/v. The degree of substitution (DS for the OSA-modified starch ranged from 0.0012 to 0.0055. The amylose leaching values of native and OSA-modified potato starch with different DS levels were in the range of 47.09-87.32%. The gel strength values of the OSA-modified starch were lower than those of native potato starch. Rapid Visco Analyzer data showed that peak, hot pasting, final and setback viscosities of the native starch decreased after OSA modification. Dynamic shear rheological tests, conducted at 4 °C, indicated that OSA-modified potato starch had weak gel-like behavior with the storage moduli (G' higher than the loss moduli (G” over most of the frequency ranges (0.63-63.8 rad·s-1.

  2. Comparative Emulsifying Properties of Octenyl Succinic Anhydride (OSA)-Modified Starch: Granular Form vs Dissolved State

    Science.gov (United States)

    Marefati, Ali; Gutiérrez, Gemma; Wahlgren, Marie; Rayner, Marilyn

    2016-01-01

    The emulsifying ability of OSA-modified and native starch in the granular form, in the dissolved state and a combination of both was compared. This study aims to understand mixed systems of particles and dissolved starch with respect to what species dominates at droplet interfaces and how stability is affected by addition of one of the species to already formed emulsions. It was possible to create emulsions with OSA-modified starch isolated from Quinoa as sole emulsifier. Similar droplet sizes were obtained with emulsions prepared at 7% (w/w) oil content using OSA-modified starch in the granular form or molecularly dissolved but large differences were observed regarding stability. Pickering emulsions kept their droplet size constant after one month while emulsions formulated with OSA-modified starch dissolved exhibited coalescence. All emulsions stabilized combining OSA-modified starch in granular form and in solution showed larger mean droplet sizes with no significant differences with respect to the order of addition. These emulsions were unstable due to coalescence regarding presence of free oil. Similar results were obtained when emulsions were prepared by combining OSA-modified granules with native starch in solution. The degree of surface coverage of starch granules was much lower in presence of starch in solution which indicates that OSA-starch is more surface active in the dissolved state than in granular form, although it led to unstable systems compared to starch granule stabilized Pickering emulsions, which demonstrated to be extremely stable. PMID:27479315

  3. Epoxy/anhydride thermosets modified with end-capped star polymers with poly(ethyleneimine cores of different molecular weight and poly(ε–caprolactone arms

    Directory of Open Access Journals (Sweden)

    C. Acebo

    2015-09-01

    Full Text Available Multiarm star polymers, with a hyperbranched poly(ethyleneimine (PEI core and poly(ε-caprolactone (PCL arms end-capped with acetyl groups were synthesized by ring-opening polymerization of ε-caprolactone from PEI cores of different molecular weight. These star polymers were used as toughening agents for epoxy/anhydride thermosets. The curing process was studied by calorimetry, thermomechanical analysis and infrared spectroscopy. The final properties of the resulting materials were determined by thermal and mechanical tests. The addition of the star polymers led to an improvement up to 130% on impact strength and a reduction in the thermal stresses up to 55%. The structure and molecular weight of the modifier used affected the morphology of the resulting materials. Electron microscopy showed phase-separated morphologies with nano-sized fine particles well adhered to the epoxy/anhydride matrix when the higher molecular weight modifier was used.

  4. Preparation of Cu/TiO2-Al2O3 Catalysts for Vapor-Phase Hydrogenation of Maleic Anhydride to g-Butyrolactone at Atmospheric Pressure%用于顺酐常压气相加氢制g-丁内酯的Cu/TiO2-Al2O3催化剂

    Institute of Scientific and Technical Information of China (English)

    王雨勃; 郭杨龙; 郭耘; 王筠松; 卢冠忠

    2003-01-01

      The effects of different preparation methods for Cu/TiO2-Al2O3 catalysts, such as stepwise impregnation method, co-impregnation method, sol-gel method, and co-precipitation method, and activation modes on vapor-phase hydrogenation of maleic anhydride (MA) to g-butyrolactone (GBL) at atmospheric pressure were investigated in this paper. The catalyst prepared by co-precipitation method exhibited higher performance over the temperature range of 180~270°C, in which the conversion of MA and selectivity of GBL was nearly 100% and 93.2%~99.3%, respectively.%  研究了不同制备方法(分步浸渍法,共浸渍法,溶胶凝胶法和共沉淀法)和还原方式对用于顺酐常压气相加氢制g-丁内酯Cu/TiO2-Al2O3催化剂性能的影响,并对影响因素进行了初步探讨.结果表明,用共沉淀法制备的催化剂具有较好的催化性能,当反应温度在180~270°C范围内,催化剂的活性和选择性分别为100%和93.2%~99.3%.

  5. 苯乙烯-马来酸酐共聚物对20%除虫脲悬浮剂分散稳定性的影响%Effect of Styrene-Maleic Anhydride Copolymer on the Dispersibility of 20% Diflubenzuron Suspension Concentrate

    Institute of Scientific and Technical Information of China (English)

    孙停停; 张树芹; 路福绥; 陈甜甜

    2012-01-01

    With benzoyl peroxide as initiator, a series of stysene-maleic anhydride copolymer was prepared by solution copolymerization under different temperatures. Polystyrene-maleic anhydride sulfonic acid sodium (SSMA) with different relative molecular mass was obtained by sulfonated the polystyrene-maleic anhdride. The dispersibility of 20% diflubenzuron suspension concentrate was identified by assaying and analyzing the diameter of particles, Zeta potentials and viscosities. The results showed that the optimal dispersant was SSMA, which was prepared at 75℃ , and the most suitable concentration was 3% . At pH =9, the dispersion stability of suspension concentrate was the best due to the strong steric hindrance provided by completely ionizing of the molecules. Na+ or Ca2+ was able to decrease the absolute value of Zeta potential by compressing the electronic double layer thickness of particles surface, which could lead to particles aggregation due to the reduction of electric quantity and ultimately deteriorate the dispersive effect of suspension concentrate. If the ions concentration were the same, the coagulation capacity by Ca2 + was stronger than that of Na+ , and the dispersion stability of suspension was worse after adding Ca2 +.%以过氧化苯甲酰为引发剂,采用溶液共聚法在不同温度下合成了一系列苯乙烯-马来酸酐共聚物,经磺化制得不同相对分子质量的聚苯乙烯-马来酸酐磺酸钠(SSMA).通过测定平均粒径、Zeta电势、黏度等考察了SSMA对20%除虫脲悬浮剂分散稳定性的影响.结果表明,最佳分散剂为75℃聚合得到的SSMA,其质量分数为3%时,水悬浮剂的分散稳定性最好;当pH=9时SSMA分子完全电离,能为颗粒提供较大的空间势垒,水悬浮剂分散稳定性最好;Na+或Ca2+压缩颗粒界面的双电层,降低Zeta电势的绝对值,使颗粒因带电量减少而聚结,导致水悬浮剂分散稳定性变差;当离子浓度相同时,Ca2+的

  6. Telechelic polyisobutylene with unsaturated end groups and with anhydride end groups

    NARCIS (Netherlands)

    Walch, E.; Gaymans, R.J.

    1994-01-01

    Anhydride terminated polyisobutylene (PIB) oligomers were synthesized in a one- or two-step process from chlorine terminated oligomers. In the one-step process, chlorine functional oligomers were just heated in the presence of maleic anhydride (MA) for 12 h at 190°C without a catalyst. In the two-st

  7. HDPE-g-MAH改性氢氧化铝阻燃PP%Investigation on blend of polypropylene and aluminium trihydroxide modified with maleic anhydride grafting polyethylene

    Institute of Scientific and Technical Information of China (English)

    段玉丰; 付朝霞; 马劲松

    2007-01-01

    在液相中用马来酸酐接枝高密度聚乙烯(HDPE-g-MAH)表面改性Al(OH)3以改善其在高分子基相中的分散性.形态观察表明,用适量HDPE-g-MAH处理Al(OH)3可改善Al(OH)3,在聚丙烯(PP)中的分散性,从而提高体系的力学性能;HDPE-g-MAH用量过多造成的Al(OH),粒子间桥联,该现象经熔融混合后依然存在,导致力学性能降低.偏光显微镜观察显示,适量HDPE-g-MAH处理Al(OH)3可改善PP的结晶形态.

  8. Fast and highly-efficient removal of methylene blue from aqueous solution by poly(styrenesulfonic acid-co-maleic acid)-sodium-modified magnetic colloidal nanocrystal clusters

    Science.gov (United States)

    Song, Yu-Bei; Lv, Shao-Nan; Cheng, Chang-Jing; Ni, Guo-Li; Xie, Xiao-Wa; Huang, Wei; Zhao, Zhi-Gang

    2015-01-01

    Magnetic colloidal nanocrystal clusters (MCNCs) modified with different amounts of poly(4-styrenesulfonic acid-co-maleic acid) sodium (PSSMA) have been prepared through simple one-step solvothermal method for removal of methylene blue (MB) from aqueous solution. The prepared MCNCs are characterized by Fourier transform infrared (FT-IR) spectra, scanning electron microscope (SEM), transmission electron microscope (TEM), thermogravimetric analysis (TGA), vibrating sample magnetometer (VSM), X-ray diffraction (XRD), nitrogen adsorption-desorption technique and dynamic light scattering (DLS). Moreover, effects of the solution pH, contact time, adsorbent dosage, ionic strength and initial dye concentration on MB adsorption onto the MCNCs are systematically investigated. The PSSMA-modified MCNCs show fast and highly-efficient MB removal capacity, which dramatically depends on the immobilization amounts of PSSMA, solution pH and adsorbent dosage. Their adsorption kinetics and isotherms exhibit that the kinetics and equilibrium adsorptions can be well-described by pseudo-second-order kinetic and Langmuir model, respectively. These magnetic nanocomposites, with high separation efficiency, low production cost and recyclable property, are promising as functional adsorbents for efficient removal of cationic organic pollutants from aqueous solution.

  9. Graft Reactions of Polyethylene Glycol Bearing Different End Functional Groups with Polypropylene Grafted Maleic Anhydride%不同端基官能团PEG与聚丙烯接枝马来酸酐的接枝反应

    Institute of Scientific and Technical Information of China (English)

    董英伟; 徐建峰; 朱梦冰; 俞强

    2012-01-01

    The end-hydroxy groups of poly(ethylene glycol) methyl ether(MPEG) were converted into end-amino and end-isocyanate groups,respectively,by step reactions of MPEG with para-toluenesulfonamide and phthalimide potassiumand,and/or by the reaction of MPEG with diisocyanate.The graft reactions between polypropylene grafted maleic anhydride(MPP) and MPEG with different end groups were conducted in xylene,in order to prepare graft copolymer of polypropylene and polyethylene glycol(PP-g-PEG).FT-IR and 1H-NMR were used to characterize structure of the reaction products.It was found that the reactivity of the end-functional groups of MPEG in the reaction with MPP follows this order:-NCO〉-NH2〉-OH.For MPP/MPEG-NCO reaction system,reaction extent and PEG grafting ratio increase when the molar ratio of(NCO)/(anhydride) raises from 1∶1 to 5∶1.However,the reaction extent and the number of PEG chains grafted onto PP chains decrease when the molecular weight of MPEG increases from 1000 to 6000.%利用羟基与对甲苯磺酰氯和邻苯二甲酰亚胺钾的分步反应或者与二异氰酸酯的反应,将聚乙二醇单甲醚(MPEG)的端羟基分别转化为端氨基和端异氰酸酯基。将带有端羟基、端胺基和端异氰酸酯基的MPEG分别与聚丙烯接枝马来酸酐(MPP)反应,制备聚丙烯/聚乙二醇接枝共聚物,并比较不同体系的动力学。MPEG端基官能团与MPP链上马来酸酐的反应活性顺序为:-NCO〉-NH2〉-OH。在端异氰酸酯基MPEG与MPP反应体系中,随n(NCO)/n(MAH)增大,PEG接枝率增大;随MPEG分子量增大,接枝到PP链上的PEG支链数目减少。

  10. PREPARATION AND CHARACTERIZATION OF COMPOSITES COMPRISING MODIFIED HARDWOOD AND WOOD POLYMERS/POLY(VINYL CHLORIDE

    Directory of Open Access Journals (Sweden)

    Ruxanda Bodîrlău

    Full Text Available Chemical modification of hardwood sawdust from ash-tree species was carried out with a solution of maleic anhydride in acetone. Wood polymers, lignin, and cellulose were isolated from the wood sawdust and modified by the same method. Samples were characterized by Fourier transform infrared spectroscopy (FTIR, providing evidence that maleic anhydride esterifies the free hydroxyl groups of the wood polymer components. Composites comprising chemically modified wood sawdust and wood polymers (cellulose, lignin-as variable weight percentages-, and poly (vinyl chloride were obtained and further characterized by using FTIR spectroscopy and scanning electron microscopy (SEM. The thermal behavior of composites was investigated by using the thermogravimetric analysis (TGA. In all cases, thermal properties were affected by fillers addition.

  11. 聚乳酸接枝马来酸酐/丙烯酸丁酯共聚物的制备与性能∗%Preparation and properties of maleic anhydride/butyl acrylate grafted poly(lactic acid)copolymer

    Institute of Scientific and Technical Information of China (English)

    罗卫华; 袁彩霞; 王正良; 向世欢; 聂鹏; 袁光明

    2015-01-01

    Maleic anhydride (MAH)/butyl acrylate (BA)grafted poly(lactic acid)(PLA)copolymers (mPLAs) were prepared through solution grafting copolymerization using benzoyl peroxide as initiator,MAH and BA as monomers.The structure and properties of the graft copolymers were characterized by Fourier transform infra-red spectroscopy (FT-IR),wide-angle X-ray diffraction (WAXD),differential scanning calorimetry (DSC)and thermogravimetry (TG).The monomer graft degree on PLA first increases and then decreases with increasing mass ratio of BA to MAH.It reaches the highest value of 1.96% when the mass ratios of BA to MAH and MAH to PLA are 1/1 and 3/100 respectively.Compared with the pure PLA,mPLAs exhibit lower crystallinity and decreased thermal stability.A higher monomer graft degree was associated with a lower crystallinity of the samples.With the increase of mass ratio of BA to MAH,both the melting temperature and glass transition temperature of mPLAs have a trend of declining.%以马来酸酐(MAH)和丙烯酸丁酯(BA)为单体,通过溶液接枝法制备了聚乳酸(PLA )接枝MAH/BA共聚物(mPLA).使用红外光谱(FT-IR)、广角X 射线衍射(WAXD)、差示扫描量热仪(DSC)、热重分析仪(TG)研究了接枝共聚物的结构和性能.结果表明,随着单体质量比BA/MA H 的增加,单体在PLA 上的接枝率出现先增大后减小的趋势,当m(MAH)/m (BA )=1/1,m (MAH )/m (PLA )=3/100时,制备的 mPLA 接枝率最高为1.96%;与纯PLA相比,mPLA 的结晶度和热稳定性均比有所下降,且样品的接枝率越大其结晶度越低;随着单体中BA含量的增加,mPLA 的熔融温度和玻璃化转变温度有减小的趋势.

  12. 21 CFR 177.1820 - Styrene-maleic anhydride copolymers.

    Science.gov (United States)

    2010-04-01

    ... articles that contact food of Types I, II, III, IV-A, IV-B, V, VI-B (except carbonated beverages), VII-A...; for use (except carbonated beverage bottles) as articles or as components of articles that contact...

  13. Improvement in compatibility and mechanical properties of modified wood fiber/polypropylene composites

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    To improve the interfacial compatibility between wood fibers and polypropylene and the toughness of wood-fiber/polypropylene composites,maleic anhydride grafted polypropylene (PP-g-MAH) and maleic anhydride grafted styrene-ethylene-butadiene-styrene copolymers (SEBS-g-MAH) were used as modifiers.Mechanical properties of wood-fiber/polypropylene (WF/PP) composites were improved when PP-g-MAH or SEBS-g-MAH was added.When either of these copolymers was added,the composites had better interfacial compatibility than the unmodified composite.This was verified by scanning electron microscope (SEM) observations and dynamic mechanical analysis (DMA).The mechanical properties of the composites were significantly improved because of the good interfacial bonding between wood fibers and polypropylene when PP-g-MAH and SEBS-g-MAH were added.

  14. Synthesis and characterization of biodegradable polymer: Poly (ethene maleic acid ester-co-D,L-lactide acid)

    Institute of Scientific and Technical Information of China (English)

    Mei Na Huang; Yan Feng Luo; Jia Chen; Yong Gang Li; Chun Hua Fu; Yuan Liang Wang

    2007-01-01

    A novel biodegradable polymer-poly (ethene maleic acid ester-co-D,L-lactide acid) was synthesized by copolymerizing lactide and prepolymer, which was prepared by the condensation of maleic anhydride and glycol, using p-toluene sulphonic acid as a catalyst, attempting to improve the hydrophilicity, increase flexibility and modulate the degradation rate. FTIR, 1H NMR, MALLS and DSC were employed to characterize these polymers.

  15. A self-crosslinking thermosetting monomer with both epoxy and anhydride groups derived from Tung oil fatty acids: Synthesis and properties

    Science.gov (United States)

    A self-crosslinking compound with epoxy groups and anhydride groups (GEMA) has been successfully synthesized from Tung oil fatty acid by reacting with maleic anhydride via the Diels-Alder reaction. GEMA has very good storage stability and can be cured with trace amounts of tertiary amine. This advan...

  16. 高剪切应力对苯乙烯-乙烯/丁烯-苯乙烯三嵌段聚合物马来酸酐化反应的影响%Influence of high shear stress on functionalization of maleic anhydride with styrene-ethylene/butylene-styrene terblock polymer

    Institute of Scientific and Technical Information of China (English)

    杜丽; 张玲; 张云灿

    2013-01-01

    The functionalization reaction of styrene-ethylene/butylene-styrene terblock polymer (SEBS) with maleic anhydride (MAH) was investigated through the high shear stress-induced initiation by increasing the screw rotation speed of twin-screw extruder.The results showed that the percent of grafting and the melt flow rate of functionalized products (SEBS-g-MAH) increased obviously with the increase of screw rotation speed,indicating that the high shear stress produced by increasing screw rotation speed led to the chain scission and the macro-radical,thus initiating the grafting reaction between SEBS and MAH.The crosslinking reaction could be effectively suppressed through increasing screw rotation speed to prepare the functionalized product SEBS-g-MAH with higher percent of grafting (mass fraction 0.79%-0.89%) and appropriate melt flow rate (1.859-4.398 g/min) and lower gel content (no more than mass fraction 0.32%).Meanwhile,the toughening effect of SEBS-g-MAH on nylon (PA 66) was much better.The Izod notched impact strength of the blend reached up to 94 kJ/m2,which was 30 times more than that of pure PA 66 without significant decrease of tensile and flexural strengthes.%通过提高双螺杆挤出机螺杆转速的应力引发方法,研究了高剪切应力下马来酸酐(MAH)与苯乙烯-乙烯/丁烯-苯乙烯三嵌段聚合物(SEBS)的官能化反应.结果表明,随着双螺杆挤出机螺杆转速的提高,官能化产物的接枝率和熔体流动速率明显增大.高剪切应力的作用引起大分子链断链,形成大分子自由基,从而引发SEBS的接枝反应.通过提高螺杆转速可有效地抑制交联副反应,制得接枝率较高(质量分数0.79%~0.89%)、熔体流动速率适宜(1.859 ~4.398 g/min)和凝胶含量较低(质量分数不大于0.32%)的官能化产物.同时,由应力诱导引发所得官能化产物SEBS-g-MAH对尼龙(PA 66)的增韧效果较好,其共混物的悬臂梁缺口冲击强度能达到约94 kJ/m2,

  17. Pharmacokinetics of Maleic Acid as a Food Adulterant Determined by Microdialysis in Rat Blood and Kidney Cortex

    Directory of Open Access Journals (Sweden)

    Mei-Ling Hou

    2016-03-01

    Full Text Available Maleic acid has been shown to be used as a food adulterant in the production of modified starch by the Taiwan Food and Drug Administration. Due to the potential toxicity of maleic acid to the kidneys, this study aimed to develop an analytical method to investigate the pharmacokinetics of maleic acid in rat blood and kidney cortex. Multiple microdialysis probes were simultaneously inserted into the jugular vein and the kidney cortex for sampling after maleic acid administration (10 or 30 mg/kg, i.v., respectively. The pharmacokinetic results demonstrated that maleic acid produced a linear pharmacokinetic phenomenon within the doses of 10 and 30 mg/kg. The area under concentration versus time curve (AUC of the maleic acid in kidney cortex was 5-fold higher than that in the blood after maleic acid administration (10 and 30 mg/kg, i.v., respectively, indicating that greater accumulation of maleic acid occurred in the rat kidney.

  18. Preparation of Octenyl Succinic Anhydride Modified Broken Rice Starch%辛烯基琥珀酸碎米淀粉酯的制备

    Institute of Scientific and Technical Information of China (English)

    苟林; 王泽南; 韩堂健; 蒋艳; 徐春泽

    2011-01-01

    Broken rice starch was modified with octenyl succinic anhydride in aqueous slurry system.The modification process was optimized by one-factor-at-a-time and orthogonal array design methods to achieve maximum degree of substitution(DS).The results showed that the optimal process conditions were found to be: starch slurry concentration 30%,pH 8.5,reaction time 5 h,and reaction temperature 35 ℃.Under the optimal conditions,the degree of substitution was 0.01445.%以碎米淀粉为原料,采用湿法制备辛烯基琥珀酸碎米淀粉酯,以取代度为评价指标,确定辛烯基琥珀酸酐添加量为3%,通过单因素与正交试验确定辛烯基琥珀酸碎米淀粉酯的最佳制备工艺。结果显示:淀粉乳质量分数30%、pH8.5、反应时间5h、反应温度35℃为最佳工艺条件,在此条件下所得产品取代度可达0.01445。

  19. 响应面分析优化菊粉的十二烯基琥珀酸酐改性工艺研究%Study on dodecenly succinic anhydride-modified inulin

    Institute of Scientific and Technical Information of China (English)

    李丹丹; 曹威; 周杰; 李静鹏

    2013-01-01

    为了研究菊糖的十二烯基琥珀酸酐改性工艺条件,以菊糖、硼氢化钠及十二烯基琥珀酸酐用量、反应时间、反应pH以及反应温度为影响因素,以十二烯基琥珀酸酐的取代度为考察指标,运用Plackett-Burman设计筛选出3个对菊糖的十二烯基琥珀酸酐取代度影响显著因素,即十二烯基琥珀酸酐用量、反应pH和反应时间.用响应面分析实验优化十二烯基琥珀酸菊糖酯改性工艺.十二烯基琥珀酸菊糖酯改性最优工艺:菊糖4g,硼氢化钠0.015g,十二烯基琥珀酸酐0.94g,反应时间为6.8h,反应pH8.5,反应温度35℃,菊糖的十二烯基琥珀酸酐取代度为0.0140±3.33E-05.%In order to study optimum conditions for dodecenly succinic anhydride-modified inulin,effects of the amount of inulin,the dosage of sodium borohydride and dodecenly succinic anhydride (DDSA),pH,time and temperature used on the degree of substitution of dodecenly succinic anhydride-modified inulin were investigated.Plackett-Burman was adopted to screen out the important factors,which were the dosage of dodecenly succinic anhydride,pH and time used.The optimum reaction conditions were obtained by response surface analysis..inulin 4g,sodium borohydride 0.015g,dodecenly succinic anhydride 0.94g,time 6.8h,pH8.5,temperature 35℃,and the degree of substitution of dodecenly succinic anhydride-modified inulin is 0.0140± 3.33E-05.

  20. Thermal curing of an epoxy-anhydride system modified with hyperbranched poly(ethylene imine)s with different terminal groups

    OpenAIRE

    Morancho Llena, José María; Fernández Francos, Xavier; Acebo Gorostiza, Cristina; Ramis Juan, Xavier; Salla Tarragó, José María; Serra Albet, Àngels

    2017-01-01

    New hyperbranched polymers (HBP) have been synthesized by reaction of a poly(ethylene imine) with phenyl and t-butyl isocyanates. These HBPs have been characterized by 1H-NMR (nuclear magnetic resonance of hydrogen) and Fourier transform infrared spectroscopy. Their influence on the curing and properties of epoxy-anhydride thermosets has been studied by different techniques: differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and thermogravimetry (TG). The ...

  1. α-Costic anhydride

    Directory of Open Access Journals (Sweden)

    Moha Berraho

    2010-03-01

    Full Text Available The title compound [systematic name: 2-(4a,8-dimethyl-1,2,3,4,4a,5,6,8a-octahydronaphthalen-2-ylacrylic acid anhydride], C30H42O3, is a new isocostic anhydride which was synthesized from the aerial part of Inula Viscosa (L Aiton [or Dittrichia Viscosa (L Greuter]. The molecule adopts an essentially linear shape with two terminal fused-rings bridged by the anhydride group. The external rings have the same conformation (half-chair while each of the two inner rings has an almost ideal chair conformation. In the crystal, intermolecular C—H...O interactions link the molecules into a two-dimensional array in the bc plane.

  2. α-Costic anhydride.

    Science.gov (United States)

    Tebbaa, Mohamed; Akssira, Mohamed; Elhakmaoui, Ahmed; El Ammari, Lahcen; Benharref, Ahmed; Berraho, Moha

    2010-02-13

    THE TITLE COMPOUND [SYSTEMATIC NAME: 2-(4a,8-dimethyl-1,2,3,4,4a,5,6,8a-octa-hydro-naphthalen-2-yl)acrylic acid anhydride], C(30)H(42)O(3), is a new isocostic anhydride which was synthesized from the aerial part of Inula Viscosa- (L) Aiton [or Dittrichia Viscosa- (L) Greuter]. The mol-ecule adopts an essentially linear shape with two terminal fused-rings bridged by the anhydride group. The external rings have the same conformation (half-chair) while each of the two inner rings has an almost ideal chair conformation. In the crystal, inter-molecular C-H⋯O inter-actions link the mol-ecules into a two-dimensional array in the bc plane.

  3. Chemically Modified Chitosan Beads as Molecularly Imprinted Polymer Matrix for Adsorptive Separation of Proteins

    Institute of Scientific and Technical Information of China (English)

    Tian Ying GUO; Yong Qing XIA; Guang Jie HAO; Bang Hua ZHANG

    2004-01-01

    In a phosphate buffer, a hemoglobin (Hb)-imprinted polymer complex was prepared using maleic anhydride (MAH) modified chitosan beads as matrix, acrylamide (AM) as functional monomer, N,N-methylenebisacrylamide (MBA) as cross-linker and potassiumpersulfate (KPS)/sodium hydrogen sulfite (NaHSO3) as initiators. Langmuir analysis showed that an equal class of adsorption was formed in the molecular imprinting polymer (MIP), and the MIP has high adsorption capacity and selectivity for the imprinted molecule. The MIP can be reused and the recovery was approximately 100% at low concentration.

  4. Selective Oxidation of n-Butane over VPO Catalyst Modified by Different Additives

    Institute of Scientific and Technical Information of China (English)

    Hong Liang; Daiqi Ye

    2005-01-01

    A series of vanadyl pyrophosphate catalyst (VPO) modified by different additives have been prepared with the aim to study the performance for selective conversion of n-butane to maleic anhydride(MA). The addition of various promoters improved the catalytic performance remarkably on both activity and selectivity. The correlation of activity and selectivity of the catalysts with their structure has been discussed. The increase in BET surface areas and surface redox sites leads to an enhanced activity. However,good selectivity can only be obtained on those surfaces with suitable surface acid sites.

  5. 改性马来酸酐橡胶接枝物增韧尼龙6的制备及表征%Preparation and characterization of modified maleic anhydride graft rubber toughened nylon 6

    Institute of Scientific and Technical Information of China (English)

    顾晓华; 张希伟; 曾鹏; 宋雪; 程伟东

    2015-01-01

    为了促进橡胶接枝物与尼龙6(PA6)的相容性并提高增韧效果,利用马来酸酐和对苯二胺合成了一种含酰胺键的二元羧酸,命名为对苯马来二酰胺二酸(改性马来酸酐,MDMA),并将MDMA接枝到三元乙丙橡胶(EPDM)上,制备出不同接枝率的改性马来酸酐橡胶接枝物(EPDM-g-MDMA),以EPDM-g-MDMA与PA6质量比为30∶70,通过共混挤出制备了含不同接枝率接枝物的EPDM-g-MDMA/PA6共混物.通过核磁共振和红外光谱对MDMA进行了测试,表明成功合成了所需要的二元羧酸.对共混物进行了相容性测试、DSC、熔融指数(MI)、SEM、拉伸和冲击力学性能测试.结果表明:随着接枝率的增大,共混物的熔融峰温度略有降低,其熔体黏度不断增大,橡胶接枝物在PA6基体中有良好的分散性,使EPDM-g-MDMA/PA6共混物的冲击强度提高了5.5倍,说明EPDM-g-MDMA对PA6的增韧效果较为明显.

  6. 马来酸酐改性的丙烯-丁烯共聚物的溶度参数%The Solubility Parameter of Propylene-butene Copolymers Modified with Maleic anhydride

    Institute of Scientific and Technical Information of China (English)

    刘大壮; 董雪茹

    2004-01-01

    在聚烯烃分子上接枝马来酸酐的主要目的是增加分子的极性.在比较了多种处理方法之后,提出了一种用缔合力参数和溶度参数表示的新的二维方法处理马来酸酐接枝改性的丙烯丁烯共聚物溶解度数据.溶剂的缔合力参数可以用Hansen的三维溶度参数计算出来.结果发现可溶区的形状是一个椭圆,这个椭圆可以用来表示聚合物溶度参数的范围.PPB-MAH的缔合力参数可以用来量化表示其分子极性,椭圆方程可以用作溶剂的可溶性的预测.

  7. Study on the properties of cassava hydroxypropyl and octenyl succinic anhydride compound modified starch%木薯羟丙基化辛烯基琥珀酸酯化复合改性淀粉的性质研究

    Institute of Scientific and Technical Information of China (English)

    雷欣欣; 张本山; 周雪

    2012-01-01

    以木薯淀粉为原料制备木薯羟丙基化辛烯基琥珀酸酯化复合改性淀粉,采用傅里叶变换红外谱仪、扫描电镜、X射线衍射仪和Brabender黏度仪等对木薯羟丙基化辛烯基琥珀酸酯化复合改性淀粉的物化性质进行了测定和分析.并与木薯原淀粉和木薯辛烯基琥珀酸淀粉酯进行对比。结果表明,木薯淀粉经复合改性后,在1550-1610cm-1出现新的吸收峰.与原木薯淀粉和木薯SSOS相比,在940、880、730、570cm-1处呈现较弱的吸收峰;复合改性后颗粒表面受损严重.颗粒的形状也发生明显改变,但晶体类型没有发生改变;乳化性能和透明度得到提高;起糊温度、峰值温度降低.糊粘度增大;与单一的辛烯基琥珀酸酯化改性淀粉相比,热糊稳定性升高,凝沉性增强。%The cassava starch was used to prepare cassava hydroxypropyl and octenyl succinic anhydride compound modified starch. The physical properties of cassava hydroxypropyl and octenyl succinic anhydride compound modified starch were investigated by Fourier transform infrared spectrometer(FT-IR),Scanning electron microscop,X-ray diffraction(XRD),Brabender viscometer and so on with the comparison of the native cassava starch and octenyl succinic anhydride(OSA)-modified cassava starch. The results indicated that the FT-IR spectrum of compound modified cassava starch showed new absorption peaks at 1550-1610cm-1. and weaken absorption peak at the 940,880,730 and 570cm-1,compared with the native cassava starch and OSA- modified cassava starch. The starch granule exhibited rougher surface,more irregular shape significantly but the crystalline was not changed. The product showed good emulsifiability and transparency. That gelatinization temperature and the peak temperature all decreased,and paste viscosity was higher as well.The setback capacity was weaker,and hot paste stability increased,compared with single octenyl succinic anhydride

  8. Ferrocenecarboxylic anhydride: a redetermination

    Directory of Open Access Journals (Sweden)

    C. John McAdam

    2016-11-01

    Full Text Available The title molecule, [Fe2(C5H52(C12H8O3], briefly reported previously [Zhang (2015. Private Communication (CCDC reference 1056736. CCDC, Cambridge, England], comprises two ferrocenyl units connected by an acid anhydride bridge. Both ferrocene units have near coplanar [dihedral angles between the ring planes = 2.84 (4 and 1.74 (13°] and eclipsed [pseudo torsion angles = 6.3 (2 and 5.1 (2°] cyclopentadienyl (Cp rings. A twist through the anhydride linkage results in a dihedral angle of 73.81 (8° between the two substituted Cp rings planes. An intramolecular C—H...O hydrogen bond is also found. In the crystal, C—H...O hydrogen bonds link the molecules into a three-dimensional network.

  9. O emprego de quitosana quimicamente modificada com anidrido succínico na adsorção de azul de metileno The use of chemical modified chitosam with succinic anhydride in the methylene blue adsorption

    Directory of Open Access Journals (Sweden)

    Ilauro S. Lima

    2006-06-01

    Full Text Available The adsorption capacity of alpha-chitosan and its modified form with succinic anhydride was compared with the traditional adsorbent active carbon by using the dye methylene blue, employed in the textile industry. The isotherms for both biopolymers were classified as SSA systems in the Giles model, more specifically in L class and subgroup 3. The dye concentration in the supernatant in the adsorption assay was determined through electronic spectroscopy. By calorimetric titration thermodynamic data of the interaction between methyene blue and the chemically modified chitosan at the solid/liquid interface were obtained. The enthalpy of the dye/chitosan interaction gave 2.47 ± 0.02 kJ mol-1 with an equilibrium constant of 7350 ± 10 and for the carbon/dye interaction this constant gave 5951 ± 8. The spontaneity of these adsorptions are reflected by the free Gibbs energies of -22.1 ± 0.4 and -21.5 ± 0.2 kJ mol-1, respectively, found for these systems. This new adsorbent derived from a natural polysaccharide is as efficient as activated carbon. However 97% of the bonded dye can be eluted by sodium chloride solution, while this same operation elutes only 42% from carbon. Chitosan is efficient in dye removal with the additional advantage of being cheap, non-toxic, biocompatible and biodegradable.

  10. Curing mechanism and kinetics of epoxy/anhydride system modified by benzoxazine%苯并嗪改性环氧酸酐体系的固化机理及动力学

    Institute of Scientific and Technical Information of China (English)

    廖进彬; 姜其斌; 曾智; 李鸿岩

    2014-01-01

    An epoxy/anhydride system was modified by aromatic diamine-based benzoxazine. The curing mechanism of the system was analyzed with Fourier transform infrared spectroscopy(FT-IR)and differential scanning calorimetry (DSC). The blend system exhibited two curing reactions in the curing process. Epoxy resin first cured with sufficient anhydride catalyzed by imidazole at 100℃, and cured completely at 150℃ for 2 h. Benzoxazine underwent ring-opening polymerization at 180℃. The curing kinetics of modified resin system was studied with non-isothermal DSC at different heating rates. The average activation energies of two reactions were calculated utilizing the Flynn-Wall-Ozawa method to be 65.27 kJ·mol-1 and 92.8 kJ·mol-1, respectively. Both curing reactions were found to be autocatalytic processes by the Friedman method, and the predicted curves from the autocatalytic model fitted well with those of experiments.%利用一种二胺型苯并嗪改性环氧酸酐体系。通过FT-IR和DSC分析了改性体系的固化机理。结果表明:共混树脂体系在固化时存在两个反应,首先是环氧树脂与足量的酸酐在咪唑作用下在100℃先开始固化,并在150℃固化2 h后固化完全,之后苯并嗪在180℃发生开环聚合。用非等温DSC法研究了该共混体系的固化动力学。采用 Flynn-Wall-Ozawa 方法求出了共混体系在固化时两个固化反应的活化能,分别为65.27 kJ·mol-1和92.8 kJ·mol-1,并利用Friedman方法判断了两个反应都是自催化反应,计算得到自催化模型曲线与实验曲线能较好地吻合。

  11. Blends of nitrile butadiene rubber/poly (vinyl chloride: The use of maleated anhydride castor oil based plasticizer

    Directory of Open Access Journals (Sweden)

    Indiah Ratna Dewi

    2016-06-01

    Full Text Available Recently, much attention has been focused on research to replace petroleum-based plasticizers, with biodegradable materials, such as biopolymer which offers competitive mechanical properties. In this study, castor oil was modified with maleic anhydride (MAH to produce bioplasticizer named maleated anhydride castor oil (MACO, and used in nitrile butadiene rubber (NBR/poly vinyl chloride (PVC blend. The effect of MACO on its cure characteristics and mechanical properties of NBR/PVC blend has been determined. The reactions were carried out at different castor oil (CO/xylene ratios, i.e. 1:0 and 1:1 by weight, and fixed CO/MAH ratio, 1:3 by mole. DOP, CO, and MACO were added into each NBR/PVC blend according to the formula. It was found that the viscosity and safe process level of NBR/PVC blend is similar from all plasticizer, however, MACO (1:0 showed the highest cure rate index (CRI. MACO-based plasticizer gave a higher value of the mechanical properties of the NBR/PVC blend as compared to DOP based plasticizer. MACO (1:1 based plasticizer showed a rather significance performance compared to another type of plasticizers both before and after aging. The value of hardness, elongation at break, tensile strength, and tear strength were 96 Shore A, 155.91 %, 19.15 MPa, and 74.47 MPa, respectively. From this result, NBR/PVC blends based on MACO plasticizer can potentially replace the DOP, and therefore, making the rubber blends eco-friendly.

  12. Anhydric maleic functionalization and polyethylene glycol grafting of lactide-co-trimethylene carbonate copolymers

    Energy Technology Data Exchange (ETDEWEB)

    Díaz, A.; Valle, L.; Franco, L. del [Departament d' Enginyeria Química, Universitat Politècnica de Catalunya, Av. Diagonal 647, Barcelona E-08028 (Spain); Sarasua, J.R. [Department of Mining-Metallurgy Engineering and Materials Science, University of the Basque Country (UPV/EHU), Bilbao (Spain); Estrany, F. [Departament d' Enginyeria Química, Universitat Politècnica de Catalunya, Av. Diagonal 647, Barcelona E-08028 (Spain); Puiggalí, J., E-mail: Jordi.Puiggali@upc.es [Department of Mining-Metallurgy Engineering and Materials Science, University of the Basque Country (UPV/EHU), Bilbao (Spain)

    2014-09-01

    Lactide and trimethylene carbonate copolymers were successfully grafted with polyethylene glycol via previous functionalization with maleic anhydride and using N,N′-diisopropylcarbodiimide as condensing agent. Maleinization led to moderate polymer degradation. Specifically, the weight average molecular weight decreased from 36,200 to 30,200 g/mol for the copolymer having 20 mol% of trimethylene carbonate units. Copolymers were characterized by differential scanning calorimetry, thermogravimetry and X-ray diffraction. Morphology of spherulites and lamellar crystals was evaluated with optical and atomic force microscopies, respectively. The studied copolymers were able to crystallize despite the randomness caused by the trimethylene carbonate units and the lateral groups. Contact angle measurements indicated that PEG grafted copolymers were more hydrophilic than parent copolymers. This feature justified that enzymatic degradation in lipase medium and proliferation of both epithelial-like and fibroblast-like cells were enhanced. Grafted copolymers were appropriate to prepare regular drug loaded microspheres by the oil-in-water emulsion method. Triclosan release from loaded microspheres was evaluated in two media. - Highlights: • Pegylated copolymers of lactide and trimethylene carbonate have been synthesized. • Grafting with polyethylene glycol was able via maleic anhydride functionalization. • Drug-loaded microspheres could be prepared from new pegylated copolymers. • Hydrophilicity of lactide/trimethylene carbonate copolymers increased by pegylation. • New pegylated copolymers supported cell adhesion and proliferation.

  13. Thermal curing of an epoxy-anhydride system modified with hyperbranched poly(ethylene imine)s with different terminal groups

    OpenAIRE

    Morancho Llena, José María; Fernández Francos, Xavier; Acebo Gorostiza, Cristina; Ramis Juan, Xavier; Salla Tarragó, José María; Serra Albet, Àngels

    2015-01-01

    Epoxy resins are widely used in applications such as adhesives, coatings, electric laminates, encapsulation of semiconductor devices, matrix material for composites, structural components and cryogenic engineering because of their mechanical properties, adhesion and chemical resistance. However, epoxy resins are inherently brittle due to their high cross-link density. To increase their toughness different modifiers such as rubber, thermoplastic and glass particles can be added, but they al...

  14. 糯玉米辛烯基琥珀酸淀粉酯糊性质的研究%Paste Properties of Octenyl Succinic Anhydride Modified Waxy Corn Starch

    Institute of Scientific and Technical Information of China (English)

    宋晓燕; 李真; 谢慧玲

    2009-01-01

    The paste properties (e.g. , viscosity, paste clarity, retrogradation, freeze-thaw stability and digestibility) of waxy maize starch before and after oetenyl succinic anhydride (OSA) modification were investigated. The results showed that the starch derivatives had higher viscosities and paste clarity, lower retrogradation and digestibility, better freeze-thaw stability. The viscosities of the starches increased from 91.7 mPa·s to 2 013.3 mPa·s with the increase of DS from 0 to 0. 0185. The light transparency increased from 37.0 % to 90.4 % ; the water precipitation decreased from 4.0 mL to 0 mL at room temperature (25℃) for 720 h; during the fourth freeze-thaw cycle, no water discharged from the gels of OSA modified starch. The paste of OSA modified starch is shear-shinning, which should belong to pseudoplastic liquid. The experiment provided the reference of the application of OSA modified starches in food industry .%为了探讨辛烯基琥珀酸淀粉酯的应用特性,对糯玉米淀粉辛烯基琥珀酸酐(OSA)改性前后淀粉糊的黏度、透明度、凝沉性和消化特性进行了研究.结果表明:经过OSA改性之后,糯玉米淀粉糊的黏度、透明度、凝沉性和冻融稳定性得到显著改善,离体消化速度下降.当取代度由0增加至0.018 5时,淀粉糊的表观黏度由91.7 mPa·s增至2 013.3 mPa·s,透光率由37.0%提高到90.4%;25℃下静置720 h时析出水的体积由4.0 mL降低为0 mL;经过4次冻融循环后无水析出.糯玉米辛烯基琥珀酸淀粉酯具有剪切变稀现象,属于假塑性流体.

  15. Properties of Octenyl Succinic Anhydride Modified Starch and Its Application in Chicken Sausages%辛烯基琥珀酸淀粉酯的特性分析及在鸡肉灌肠中的应用

    Institute of Scientific and Technical Information of China (English)

    宋晓燕; 董振江; 李真; 杨延超; 裴亚琼

    2012-01-01

    以早籼米淀粉为原料,采用水相体系制备不同黏度的辛烯基琥珀酸淀粉酯,并对其糊化特性、冻融稳定性及在鸡肉灌肠中的应用进行研究。结果表明:淀粉经酸解和辛烯基琥珀酸酐改性后,可以得到不同黏度的辛烯基琥珀酸淀粉酯,具有良好的冻融稳定性。在鸡肉灌肠中应用时,加入早籼米辛烯基琥珀酸淀粉酯的鸡肉灌肠与加入木薯变性淀粉的鸡肉灌肠相比较,其硬度、弹性和咀嚼性都有不同程度的提高(p〈0.05)。扫描电子显微镜分析显示,添加木薯变性淀粉的样品,内部结构比较蓬松,而添加早籼米OSA-H6的样品,其内部组织则相对紧实细腻。该研究表明,辛烯基琥珀酸酐改性淀粉(烯基琥珀酸淀粉酸)可以改善肉制品的质构特性,在肉制品中具有潜在的应用价值。%Octenyl succinic anhydride (OSA) modified starches with different viscosities were prepared from early indica rice starch in aqueous slurry systems. The pasting property and freeze-thaw stability of the products were analyzed and their application in chicken sausages was evaluated. The results showed that acid hydrolysis of starch followed by OSA modification produced OSA modified starch, which had better freeze-thaw stability than its native counterpart. The texture of sausages with added OSA modified indica rice starch was improved in hardness, springiness and chewiness when compared to sausages with added modified tapioca starch (P 〈 0.05). SEM observations revealed that sausages with the addition of tapioca modified starch had large pores in its structure and fluffy texture, while sausages with the addition of OSA modified indica rice starch was compact in texture. In summary, OSA modified starch can improve texture characteristics of meat products and consequently holds potential for applications in meat products.

  16. Tetrahydrofuran Unit Adopting Davy's Latest Maleic Anhydride Technology to Come Online

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ The 1,4-butanediol (BDO)/tetrahydrofuran (THF) project constructed by the Blue Star (Nanjing) New Chemical Ma-terials Co., Ltd. adopting a whole package of the world's latest patented technology will come on-stream by the end of 2008. It is told that by that time Blue Star will rank among the global leaders in terms of quality of BDO and THF products, which can substitute for around 40% of imported high-quality products.

  17. Maleic-anhydride grafted EPM as compatibilising agent in NR/BR/EPDM blends

    NARCIS (Netherlands)

    Zhang, H.; Datta, R.N.; Talma, A.G.; Noordermeer, J.W.M.

    2010-01-01

    Incorporation of approximately 30 phr Ethylene–Propylene–Diene rubber (EPDM) into natural rubber (NR)/butadiene rubber (BR) is a means to achieve non-staining ozone resistance for tire sidewall applications. However, due to incompatibility of the elastomers and heterogeneous filler distribution in e

  18. PSD Applicability for Ashland Chemical's Maleic Anhydride Plant in Neal, West Virginia

    Science.gov (United States)

    This document may be of assistance in applying the New Source Review (NSR) air permitting regulations including the Prevention of Significant Deterioration (PSD) requirements. This document is part of the NSR Policy and Guidance Database. Some documents in the database are a scanned or retyped version of a paper photocopy of the original. Although we have taken considerable effort to quality assure the documents, some may contain typographical errors. Contact the office that issued the document if you need a copy of the original.

  19. Modification of wheat starch with succinic acid/acetic anhydride and azelaic acid/acetic anhydride mixtures I. Thermophysical and pasting properties.

    Science.gov (United States)

    Subarić, Drago; Ačkar, Durđica; Babić, Jurislav; Sakač, Nikola; Jozinović, Antun

    2014-10-01

    The aim of this research was to investigate the influence of modification with succinic acid/acetic anhydride and azelaic acid/acetic anhydride mixtures on thermophysical and pasting properties of wheat starch. Starch was isolated from two wheat varieties and modified with mixtures of succinic acid and acetic anhydride, and azelaic acid and acetic anhydride in 4, 6 and 8 % (w/w). Thermophysical, pasting properties, swelling power, solubility and amylose content of modified starches were determined. The results showed that modifications with mixtures of afore mentioned dicarboxylic acids with acetic anhydride decreased gelatinisation and pasting temperatures. Gelatinisation enthalpy of Golubica starch increased, while of Srpanjka starch decreased by modifications. Retrogradation after 7 and 14 day-storage at 4 °C decreased after modifications of both starches. Maximum, hot and cold paste viscosity of both starches increased, while stability during shearing at high temperatures decreased. % setback of starches modified with azelaic acid/acetic anhydride mixture decreased. Swelling power and solubility of both starches increased by both modifications.

  20. 丁二酸酐性能及各种生产工艺介绍%The Properties and Various Production Technology of Succinic Anhydride

    Institute of Scientific and Technical Information of China (English)

    潘玉莹; 李江; 胡利娜; 肖鹏飞

    2014-01-01

    Succinic anhydride was a kind of widely used and important fine chemical raw materials , especially its derivatives of high value -added fine chemical products , succinic anhydride production process in all the world mainly divided into succinic acid dehydration and maleic anhydride hydrogenated to succinic anhydride .The properties, the application and production technology of succinic anhydride , and comparison of production technology , maleic anhydride melting catalytic hydrogenated to succinic anhydride were mainly introduced , which was one of the most competitive and promising development method due to the cost of production and the comprehensive energy consumption was low .%丁二酸酐是一种重要的精细化工原料,用途广泛,尤其它的衍生物更是附加值高的精细化工产品,全球丁二酸酐的生产工艺主要有丁二酸脱水法、顺丁烯二酸酐催化加氢法。本文章主要介绍了丁二酸酐的性能、用途和生产工艺技术,并对生产工艺技术进行了比较,顺丁烯二酸酐熔融催化加氢法由于生产成本和综合能耗较低,是最具竞争力,发展前景看好的一种方法。

  1. METRONIDAZOLE- LOADED CHITOSAN/ POLY(MALEIC ANHYDRIDEALT-VINYL ACETATE HYDROGELS FOR DENTAL TREATMENTS

    Directory of Open Access Journals (Sweden)

    Delia Mihaela RAŢĂ

    2016-06-01

    Full Text Available A new approach to prepare polymeric hydrogels was developed to obtain an efficient controlled release system for dental treatments. Hydrogels were prepared by a method of condensation through amidation, using a natural (chitosan and a synthetic polymer - poly(maleic anhydride-alt-vinyl acetate. The influence of different reaction parameters on hydrogels properties was investigated. Infrared spectroscopy studies confirmed the crosslinking by the presence of amide bonds, formed between the two polymers chains. In addition, these hydrogels presented a good release capacity, which was influenced by the reaction parameters used in the study (molar ratio between the two polymers. The cytotoxicity of these materials was investigated on human dermal fibroblasts.

  2. XPS depth profiling of derivatized amine and anhydride plasma polymers: Evidence of limitations of the derivatization approach

    Science.gov (United States)

    Manakhov, Anton; Michlíček, Miroslav; Felten, Alexandre; Pireaux, Jean-Jacques; Nečas, David; Zajíčková, Lenka

    2017-02-01

    The quantitative analysis of the chemistry at the surface of functional plasma polymers is highly important for the optimization of their deposition conditions and, therefore, for their subsequent applications. The chemical derivatization of amine and carboxyl-anhydride layers is a well-known technique already applied by many researchers, notwithstanding the known drawback of the derivatization procedures like side or uncomplete reactions that could lead to "unreliable" results. In this work, X-ray photoelectron spectroscopy (XPS) combined with depth profiling with argon clusters is applied for the first time to study derivatized amine and carboxyl-anhydride plasma polymer layers. It revealed an additional important parameter affecting the derivatization reliability, namely the permeation of the derivatizing molecule through the target analysed layer, i.e. the composite effect of the probe molecule size and the layer porosity. Amine-rich films prepared by RF low pressure plasma polymerization of cyclopropylamine were derivatized with trifluoromethyl benzaldehide (TFBA) and it was observed by that the XPS-determined NH2 concentration depth profile is rapidly decreasing over top ten nanometers of the layer. The anhydride-rich films prepared by atmospheric plasma co-polymerization of maleic anhydride and C2H2 have been reacted with, parafluoroaniline and trifluoroethyl amine. The decrease of the F signal in top surface layer of the anhydride films derivatized by the "large" parafluoroaniline was observed similarly as for the amine films but the derivatization with the smaller trifluoroethylamine (TFEA) led to a more homogenous depth profile. The data analysis suggests that the size of the derivatizing molecule is the main factor, showing that the very limited permeation of the TFBA molecule can lead to underestimated densities of primary amines if the XPS analysis is solely carried out at a low take-off angle. In contrast, TFEA is found to be an efficient

  3. WPCs-based Bamboo Powder Modified by the Compatilizer%相容剂改性竹粉基木塑复合材料

    Institute of Scientific and Technical Information of China (English)

    黄铠盛; 陈国华

    2012-01-01

    比较了MA-g-LDPE和MA-g-EVA两种相容剂对木塑复合材料的性能影响效果.结果表明:当马来酸酐接枝物的加入量为10~ 15份时,木塑复合材料的综合性能最好.利用MA-g-LDPE改性时,复合材料的拉伸强度、弯曲强度和耐热性较好,而利用MA-g-EVA改性时,复合材料在冲击强度、流动性和耐水性方面则提高较多.%The properties of bamboo powder and polypropylene composite which was modified by two kinds of maleic anhydride-grafted polymers were compared. The result showed when the compatilizer content was added in the range of 10 to 15 phr,the comprehensive properties of WPCs were optimal. With regard to compatilizer modified WPCs,anhydride-grafted LDPE made the composite better in tensile strength , flexural property and heat-resistance property than those of anhydride-grafted EVA,which exhibited enhancing impact strength,flowability and water resistance property.

  4. SYNTHESIS OF POLYURETHANE MODIFIED BISMALEIMIDE(UBMI)AND POLYURETHANE-IMIDE ELASTOMER

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Urethane modified bismaleimide(UBMI)was synthesized by the reaction of maleic anhydride(MA)with NCO group terminated polyurethane prepolymer(PUP)in presence of acetone.The product was determined by infrared analysis.Then ultrasonic assistant process was introduced into the solvent removal of the prepolymer mixture of UBMI and PUP.Polyurethane-imide(PUI)elastomer was synthesized from the above PUP-UBMI prepolymer mixture by the infusion technology with 2,5-dimethyl-2,5-bis(tert-butylperoxy)-hexane(B25)as liquid initiator at 120℃.The thermal properties and stress-strain behavior of PUI elastomer was characterised by thermogravimetric(TG)analysis and tensile testing apparatus,respectively.Compared with pure polyurethane elastomer,the PUI elastomer composite showed the better thermal stability.

  5. Antiviral activity of 3-hydroxyphthalic anhydride-modified ovalbumin against herpes simplex virus 2 in vitro%邻苯二甲酸酐修饰卵清蛋白体外抗单纯疱疹病毒Ⅱ型的活性研究

    Institute of Scientific and Technical Information of China (English)

    何丽丽; 段江曼; 裘佳寅; 于飞; 刘叔文; 李琳

    2011-01-01

    目的 研究邻苯二甲酸酐修饰卵清蛋白(3-Hydroxyphthalic anhydride-modified ovalbumin,HP-OVA)体外对抗单纯疱疹病毒Ⅱ型(HSV-2)的活性.方法 采用化学修饰的方法将3-羟基.邻苯二甲酸酐(HP)修饰卵清蛋白(OVA),合成酸酐修饰蛋白HP-OVA;选用HSV-2 333病毒株及非洲绿猴肾细胞(vero 细胞)靶细胞,采用MTT比色法检测HP-OVA的体外抗HSV-2病毒活性及其对Vero细胞的体外细胞毒性;镜检观察HP-OVA对17株阴道收集的乳酸杆菌的抑菌作用.结果 酸酐修饰卵清蛋白HP-OVA对HSV-2病毒具有明显抑制作用,其IC50为23.56±8.33 μg/ml,且其对病毒作用靶细胞毒性较低,CC50>1 mg/ml,对17株阴道乳酸杆菌均无明显抑制作用,MIC>1 mg/ml.结论 酸酐修饰蛋白HP-OVA体外有较好的抗HSV-2病毒的活性,有望被开发为预防性传播性疾病的候选杀微生物剂.%Objective To investigate the antiviral activity of 3-hydroxyphthalic anhydride-modified ovalbumin (HP-OVA) against herpes simplex virus 2 (HSV-2) in vitro. Methods By chemical modification, ovalbumin (OVA) was treated with 3-hydroxyphthalic anhydride (HP) to prepare HP-OVA. The anti-HSV-2 activity against HSV-2 333 virus in vitro and the cytotoxicity of HP-OVA in African green monkey kidney cells (Vero cells) were detected by MTT colorimetric assay. The inhibitory effects of HP-OVA on 17 strains of vaginal lactobacilli were observed by microscopy. Results Anhydride-modified ovalbumin significantly inhibited the infection by HSV-2 with an Igo of 23.56±8.33 μg/ ml. HP-OVA showed only low cytotoxicity to the host cells with a CC50over 1 mg/ml. HP-OVA did not produce significant inhibitory effect on the 17 strains of vaginal lactobacilli (MIC>1 mg/ml). Conclusion Anhydride-modified protein HP-OVA exhibits potent anti-HSV-2 activity in vitro and can be a good microbicide candidate for prevention of sexually transmitted diseases.

  6. Optimization of the dilute maleic acid pretreatment of wheat straw

    NARCIS (Netherlands)

    Kootstra, A.M.J.; Beeftink, H.H.; Scott, E.L.; Sanders, J.P.M.

    2009-01-01

    Background - In this study, the dilute maleic acid pretreatment of wheat straw is optimized, using pretreatment time, temperature and maleic acid concentration as design variables. A central composite design was applied to the experimental set up. The response factors used in this study are: (1) glu

  7. Dual-Functional Hydrazide-Reactive and Anhydride-Containing Oligomeric Hydrogel Building Blocks.

    Science.gov (United States)

    Kascholke, Christian; Loth, Tina; Kohn-Polster, Caroline; Möller, Stephanie; Bellstedt, Peter; Schulz-Siegmund, Michaela; Schnabelrauch, Matthias; Hacker, Michael C

    2017-02-08

    Biomimetic hydrogels are advanced biomaterials that have been developed following different synthetic routes. Covalent postfabrication functionalization is a promising strategy to achieve efficient matrix modification decoupled of general material properties. To this end, dual-functional macromers were synthesized by free radical polymerization of maleic anhydride with diacetone acrylamide (N-(1,1-dimethyl-3-oxobutyl)acrylamide) and pentaerythritol diacrylate monostearate. Amphiphilic oligomers (Mn 40%). Efficient hydrazide/hydrazine immobilization depending on solution pH, hydrogel ketone content as well as ligand concentration for bioconjugation was shown and reversibility of hydrazone formation was indicated by physiologically relevant hydrazide release over 7 days. Proof-of-concept experiments with hydrazido-functionalized hyaluronan demonstrated potential for covalent aECM immobilization. The presented dual-functional macromers have perspective as reactive hydrogel building blocks for various biomedical applications.

  8. Process Optimization for Synthesis of Octenyl Succinic Anhydride Modified Oxidized Sweet Potato Starch by Response Surface Analysis%响应面法优化氧化辛烯基琥珀酸甘薯淀粉酯的制备工艺

    Institute of Scientific and Technical Information of China (English)

    刘强; 邬应龙; 何靖柳

    2011-01-01

    以氧化甘薯淀粉(oxidation sweet potato starch,OSPS)为原料,制备氧化辛烯基琥珀酸甘薯淀粉酯(octenylsuccinate anhydride-oxidation sweet potato starch,OSA-OSPS)。运用响应面分析(response surface method analysis,RSA)辛烯基琥珀酸酐(octenyl succinate anhydride,OSA)添加量、pH值、温度和时间对OSA-OSPS取代度(degreeof substitution,DS)的影响,得出最佳制备工艺:酸酐添加量7%、pH8.40、温度40℃,反应时间10h。采用快速黏度分析仪(rapid viscosity analyzer,RVA)分析表明:氧化甘薯淀粉峰值黏度较低,而经过OSA酯化后,峰值黏度又会有一定程度的提高,且随DS的增加呈上升趋势。%Oxidized sweet potato starch was used as the raw material to prepare octenyl succinic anhydride(OSA) modified oxidized sweet potato starch.The effects of OSA amount,pH,temperature and reaction time on degree of substitution(DS) of OSA-modified oxidized sweet potato starch were studied employing response surface analysis.The optimum process conditions determined were as follows: OSA amount 7%,pH 8.40,temperature 40 ℃,and reaction time 10 h.Rapid viscosity analyzer(RVA) analysis showed that the peak viscosity of sweet potato starch decreased after oxidation,and increased after furthermodification with OSA with a positive correlation with DS.

  9. Performance of epoxy resin-anhydride pouring materials modified with hyperbranched polyester%超支化聚酯改性环氧-酸酐浇注树脂及性能研究

    Institute of Scientific and Technical Information of China (English)

    井丰喜; 石兆从; 张道洪

    2016-01-01

    The epoxy pouring resin was prepared by using the hydroxyl-terminated hyperbranched polyester, epoxy resin, methyl tetrahydrophthalic anhydride and silica powder as the main materials. The effects of hyperbranched polyester as the addictive on the viscosity, settleability, heat-resistance, mechanical and electrical properties of the cured pouring resin were in detail studied. The results showed that hyperbranched polyester not only increased the heat-resistance, mechanical and electrical properties of the cured pouring resin, but also effectively dispersed the silica powder into the pouring resin and improved the evenness of the mixing system.%采用端羟基超支化聚酯、环氧树脂、甲基四氢苯酐和活性硅微粉为主要材料制备了高性能环氧浇注树脂。研究了超支化聚酯对体系黏度、沉降性、耐温指数、机械性能和电性能的影响及其规律。结果表明,超支化聚酯可有效分散硅微粉,提高混合体系的均匀度,提高浇筑树脂的耐热性、机械强度和电性能。

  10. wet oxidation of maleic acid by a pumice supported copper

    African Journals Online (AJOL)

    Mgina

    materials were tested in a wet oxidation of maleic acid using air or hydrogen peroxide as an oxidant. Results ... textile, pharmaceuticals, paper and pulp .... Fourier Transform Infrared (FTIR). The ... to analysis and then run at room temperature.

  11. Crosslinking of PVA Pervaporation Membrane by Maleic Acid

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Maleic acid (MA) crosslinked polyvinyl alcohol (PVA) membrane is prepared using a high temperature esterification reaction between PVA and MA in the presence of sulfuric acid as a catalyst. The crosslinking reaction mechanism is investigated using FT-IR spectral analysis. The results indicate that maleic acid reacts with hydroxyl groups in PVA to form mono- and bis-ester in a two-step process.

  12. Preparation and Characterization of Polycarbonate Modified Multiple-walled Carbon Nanotubes

    Institute of Scientific and Technical Information of China (English)

    YU Jin-Gang; HUANG Ke-Long; LIU Su-Qin; TANG Jin-Chun

    2008-01-01

    To prepare polymer/carbon nanotube composites, polycarbonate was chosen to modify multiple-walled carbon nanotubes. Poly[(propylene oxide)-(carbon dioxide)-(ε-caprolactone)], poly(butylene-co-ε-caprolactone carbonate),and poly[(propylene oxide)-co-(carbon dioxide)-co-(maleic anhydride)] were the polycarbonates which were used to modify multiple-walled carbon nanotubes, but only soluble poly[(propylene oxide)-(carbon dioxide)-(ε-caprolactone)] modified multiple-walled carbon nanotubes could be obtained. Thermogravimetric analysis clearly indicated that more polycarbonates were attached to soluble poly[(propylene oxide)-(carbon dioxide)-(ε-caprolactone)] modified multiple-walled carbon nanotubes. The formation of surface functional groups and changes of nanotube structures and morphology were monitored by infrared spectroscopy, scanning electron microscopy and transmission electron microscopy, respectively. Because of their solubility and bioactive moieties,poly[(propylene oxide)-(carbon dioxide)-(ε-caprolactone)] modified multiple-walled carbon nanotubes may find their potential use in drug delivery.

  13. Hydrolysis of Acetic Anhydride in a CSTR

    Directory of Open Access Journals (Sweden)

    Veronica N. Coraci

    2016-05-01

    Full Text Available To find the optimal reactor volume and temperature for the hydrolysis of acetic anhydride at the lowest possible cost with a 90% conversion of acetic anhydride, a formula for the total cost of the reaction was created. Then, the first derivative was taken to find a value for the temperature. This value was then inputted into the second derivative of the equation to find the sign of the value which would indicate whether that point was a minima or maxima value. The minima value would then be the lowest total cost for the optimum reaction to take place.

  14. 马来酸酐改性蓖麻油制备耐光性聚氨酯复鞣剂--乳液性能研究%Preparation of Sunproof Polyurethane Retanning Agents with Maleic Anhydride Modified Castor Oil--Study of the Emulsions Properties

    Institute of Scientific and Technical Information of China (English)

    鲍利红; 兰云军; 张淑芬

    2006-01-01

    用马来酸酐改性蓖麻油(MCO)合成了一系列不同组成的耐光性聚氨酯复鞣剂水乳液(MC-PUR),研究了复鞣剂中-COOH质量分数、n(NCO)/n(OH)、m(MCO)/m(PEG1000)对乳液电导率、黏度、临界聚沉值(CC.C)、耐酸稳定性的影响.结果表明,随-COOH质量分数从3%增大到7%,电导率从1 556 μs/cm增大到3 435 μs/cm,黏度先从168 mPa · s增大到224 mPa · s,后又降低到85 mPa · s,当w(-COOH)=5%时,黏度达到最大值;随n(NCO)/n(OH)从0.5增大到0.9,电导率从2 943 μs/cm降到2 464 μs/cm,黏度从428 m Pa · s降到224 mPa · s;随m(MCO): m(PEG1000)从1: 1增大到3: 0,黏度从224 mPa · s降到67 mPa · s;CC.C随-COOH质量分数增加和m(MCO)/m(PEG1000)增大而降低;耐酸稳定性结果证明,当w(-COOH)=3%~5%,m(MCO): m(PEG1000)=1: 1,n(NCO)/n(OH)=0.5~0.9时,MC-PUR适用于皮革复鞣工序.

  15. Morphological studies on block copolymer modified PA 6 blends

    Science.gov (United States)

    Poindl, M.; Bonten, C.

    2014-05-01

    Recent studies show that compounding polyamide 6 (PA 6) with a PA 6 polyether block copolymers made by reaction injection molding (RIM) or continuous anionic polymerization in a reactive extrusion process (REX) result in blends with high impact strength and high stiffness compared to conventional rubber blends. In this paper, different high impact PA 6 blends were prepared using a twin screw extruder. The different impact modifiers were an ethylene propylene copolymer, a PA PA 6 polyether block copolymer made by reaction injection molding and one made by reactive extrusion. To ensure good particle matrix bonding, the ethylene propylene copolymer was grafted with maleic anhydride (EPR-g-MA). Due to the molecular structure of the two block copolymers, a coupling agent was not necessary. The block copolymers are semi-crystalline and partially cross-linked in contrast to commonly used amorphous rubbers which are usually uncured. The combination of different analysis methods like atomic force microscopy (AFM), transmission electron microscopy (TEM) and scanning electron microscopy (SEM) gave a detailed view in the structure of the blends. Due to the partial cross-linking, the particles of the block copolymers in the blends are not spherical like the ones of ethylene propylene copolymer. The differences in molecular structure, miscibility and grafting of the impact modifiers result in different mechanical properties and different blend morphologies.

  16. Morphological studies on block copolymer modified PA 6 blends

    Energy Technology Data Exchange (ETDEWEB)

    Poindl, M., E-mail: marcus.poindl@ikt.uni-stuttgart.de, E-mail: christian.bonten@ikt.uni-stuttgart.de; Bonten, C., E-mail: marcus.poindl@ikt.uni-stuttgart.de, E-mail: christian.bonten@ikt.uni-stuttgart.de [Institut für Kunststofftechnik, University of Stuttgart (Germany)

    2014-05-15

    Recent studies show that compounding polyamide 6 (PA 6) with a PA 6 polyether block copolymers made by reaction injection molding (RIM) or continuous anionic polymerization in a reactive extrusion process (REX) result in blends with high impact strength and high stiffness compared to conventional rubber blends. In this paper, different high impact PA 6 blends were prepared using a twin screw extruder. The different impact modifiers were an ethylene propylene copolymer, a PA PA 6 polyether block copolymer made by reaction injection molding and one made by reactive extrusion. To ensure good particle matrix bonding, the ethylene propylene copolymer was grafted with maleic anhydride (EPR-g-MA). Due to the molecular structure of the two block copolymers, a coupling agent was not necessary. The block copolymers are semi-crystalline and partially cross-linked in contrast to commonly used amorphous rubbers which are usually uncured. The combination of different analysis methods like atomic force microscopy (AFM), transmission electron microscopy (TEM) and scanning electron microscopy (SEM) gave a detailed view in the structure of the blends. Due to the partial cross-linking, the particles of the block copolymers in the blends are not spherical like the ones of ethylene propylene copolymer. The differences in molecular structure, miscibility and grafting of the impact modifiers result in different mechanical properties and different blend morphologies.

  17. Application of modified styrene-acrylate latex as surface sizing agent%改性苯丙乳液表面施胶剂的应用

    Institute of Scientific and Technical Information of China (English)

    曹辉波; 何静; 朱磊; 全晟

    2012-01-01

    By using functional monomer maleic anhydride, modified hydroxy-ethyl methacrylate emulsion, and taking styrene, methyl methacrylate, ethyl acrylate as main monomers, polystyrene-methyl methacrylate-ethyl acrylate-maleic anhydride (PSMEM), polystyrene-methyl methacrylate-ethyl acrylate-hydroxy-ethyl methacrylate (PSMEH) polymer surface sizing agent has been synthesized respectively. Application results indicate that after dried, and sized with the 70% emulsion on the paper surface, the testing paper reached the best physical properties; PSMEH was superior to PSMEM in wet strength of the paper. PSMEH and PSMEM both made the paper good hydrophobicity.%利用功能单体马来酸酐、甲基丙烯酸羟乙酯改性苯丙乳液,苯乙烯、甲基丙烯酸甲酯、丙烯酸乙酯为主单体,分别合成聚苯乙烯-甲基丙烯酸甲酯-丙烯酸乙酯-马来酸酐(PSMEM)、聚苯乙烯-甲基丙烯酸甲酯-丙烯酸乙酯-甲基丙烯酸羟乙酯(PSMEH)聚合物表面施胶剂.应用表明:选择纸样烘干后70%乳液涂布法进行施胶对纸张的物理性质作用效果最优;PSMEH对纸张湿强度的影响优于PSMEM;PSMEH、PSMEM可使纸张具有很好的憎水性.

  18. 双环戊二烯-马来酸酐自由基共聚%Dicyclopentadiene- Maleic Anhydride Freeradical Copolymerization

    Institute of Scientific and Technical Information of China (English)

    张旭; 王小梅; 王芳; 闫卫东

    2005-01-01

    用过氧化苯甲酰(BPO)引发双环戊二烯(DCPD)与马来酸酐(MA)于70℃下进行自由基共聚,控制共聚时间使共聚转化率低于10%.用电位滴定法测定共聚物中MA的含量,测定结果与13C核磁共振(NMR)法的测定结果相吻合,相对偏差为-0.77%.13CNMR法的测定结果表明,参与自由基共聚的DCPD单元中降冰片烯与环戊烯的摩尔比为7.143.采用Fineman-Ross法测定单体的竞聚率(r),rMA=0.006 4,rDCPD=0.676 0.研究了共聚物中DCPD与MA单元的链段序列分布.

  19. P(CTFE-VAc-MAH)的合成%Synthesis of chlorotrifluoroethylene-vinyl acetate-maleic anhydride copolymer

    Institute of Scientific and Technical Information of China (English)

    刘敏; 卓虎; 侯丽华; 张书香

    2013-01-01

      要: 以超临界CO2为反应介质,制备了三氟氯乙烯(CTFE)-乙酸乙烯酯(VAc)-马来酸酐(MAH)共聚物[P(CTFE-VAc-MAH)]。考察了单体配比对聚合反应及聚合物结构、性能的影响,研究了聚合物的自乳化性能及交联反应。结果表明:在m(VAc)/m(CTFE)为6∶14的聚合体系中,增加MAH单体的比例,聚合物颗粒逐渐减小,产物中的氟含量逐渐降低;通过溶液法可使P(CTFE-VAc-MAH)共聚物形成自乳化乳液,乳胶粒的粒径随着聚合物中MAH比例的增大而变小;此共聚物在一定条件下可与多元醇或多元胺类发生交联反应。%The chlorotrifluoroethylene (CTFE)-vinyl acetate (VAc)-maleic anhydride (MAH) copolymer [P(CTFE-VAc-MAH)] was produced in supercritical carbon dioxide. The effect of monomer ratio on the polymerization and the structure and properties of the polymer was investigated, and the self-emulsifying property and the cross-linking reaction of the polymer were studied. The results show that the polymer particles become smaller and the fluorine content in the polymer gets lower gradually with increasing the amount of MAH monomer when the mass ratio of VAc to CTFE is 6∶14. P(CTFE-VAc-MAH) self-emulsifying latex can be obtained by solution method, and the sizes of the latex particles become smaller with the increase in the content of MAH in the polymer. The polymer can take place the cross-linking reaction with polyamine and polyol on certain conditions.

  20. THE STUDY AND PREPARATION OFMALEIC ANHYDRIDE GRAFTED POLYETHYLENE WAX%马来酸酐接枝聚乙烯蜡的研制

    Institute of Scientific and Technical Information of China (English)

    李颜; 杨国明; 李燕

    2000-01-01

    The influences of the kinds and amount of initiators, the amount of maleic anhydride, the temperature and time of reaction, the molecular structure of polyetylene wax on the grafting ratio, the grafting effectiveness, the odour, the colour and the crossing -linkage of maleic anhydride grafted polyethylene wax were studied. It was showed that the di -tert -butyl peroxide was an excellent initiator for the grafted reaction. The grafting ratio could reach over 1. 5 % under the amount of the initiator of 0. 2%, the amount of the maleic anlyoride of 4%, the reaction temperature of 150~160 and reation time of 3 h. The grafted wax could be used as a novel coupling agent in the plastic filler.%考察了引发剂种类用量、马来酸酐加量、反应温度、反应时间、聚乙烯蜡分子结构等因素对马来酸酐接枝聚乙烯蜡的接枝率、接枝效率、气味、颜色、交联程度的影响。结果表明二叔丁基过氧化物是一种优良的接枝反应引发剂,在引发剂加量 0.2%,马来酸酐加量4%,反应温度150~160 C,反应时间3 h的条件下,接枝率大于1.5%,该接枝蜡可作为一种新型偶联剂应用在塑料填充料中。

  1. Acetylation of barnyardgrass starch with acetic anhydride under iodine catalysis.

    Science.gov (United States)

    Bartz, Josiane; Goebel, Jorge Tiago; Giovanaz, Marcos Antônio; Zavareze, Elessandra da Rosa; Schirmer, Manoel Artigas; Dias, Alvaro Renato Guerra

    2015-07-01

    Barnyardgrass (Echinochloa crus-galli) is an invasive plant that is difficult to control and is found in abundance as part of the waste of the paddy industry. In this study, barnyardgrass starch was extracted and studied to obtain a novel starch with potential food and non-food applications. We report some of the physicochemical, functional and morphological properties as well as the effect of modifying this starch with acetic anhydride by catalysis with 1, 5 or 10mM of iodine. The extent of the introduction of acetyl groups increased with increasing iodine levels as catalyst. The shape of the granules remained unaltered, but there were low levels of surface corrosion and the overall relative crystallinity decreased. The pasting temperature, enthalpy and other gelatinisation temperatures were reduced by the modification. There was an increase in the viscosity of the pastes, except for the peak viscosity, which was strongly reduced in 10mM iodine.

  2. Introduction of Double Loop Pentadiene Modified Unsaturated Polyester Resin Production Process%浅谈双环戊二烯改性不饱和聚酯树脂的生产工艺

    Institute of Scientific and Technical Information of China (English)

    许军

    2014-01-01

    采用双环戊二烯改性不饱和聚酯树脂,使得不饱和聚酯树脂具有很多独特的优异性能。主要介绍以双环戊二烯与顺丁烯二酸酐合成双环戊二烯马来酸单酯为基础,经进一步扩链(加入多元醇酯化)之后得到不饱和聚酯树脂的合成过程。剖析了生产设备、生产工艺流程。%Based on dicyclopentadiene modified unsaturated polyester resin, unsaturated polyester resin had many unique excellent performance.The synthesis of dicyclopentadiene and maleic anhydride dicyclopentadiene maleic acid monoester as the foundation was introduced, by further expanding chain ( adding polyolsesterification) after obtaining the unsaturated polyester resin synthetic process.The production equipment and production process were analyzed.

  3. Maleic acid treatment of biologically detoxified corn stover liquor

    Science.gov (United States)

    Elimination of microbial and/or enzyme inhibitors from pretreated lignocellulose is critical for effective cellulose conversion and yeast fermentation of liquid hot-water (LHW) pretreated corn stover. In this study, xylan oligomers were hydrolyzed using either maleic acid or hemicellulases. Other so...

  4. Microwave Characterization of Propiolic Sulfuric Anhydride and Two Conformers of Acrylic Sulfuric Anhydride

    Science.gov (United States)

    Smith, CJ; Huff, Anna; Mackenzie, Becca; Leopold, Ken

    2017-06-01

    Sulfur trioxide reacts with propiolic acid and acrylic acid to form propiolic sulfuric anhydride (HC\\equivC-COOSO_{2}OH) and acrylic sulfuric anhydride (H_{2}C=CH-COOSO_{2}OH), respectively. Both species have been observed by chirped-pulse and conventional cavity microwave spectroscopy. In the case of acrylic acid, two conformers derived from the cis and trans form of the acid have been observed. The reaction mechanism and energetics are investigated by density functional theory and CCSD calculations. These results add to a growing body of evidence that establishes carboxylic sulfuric anhydrides, RCOOSO_{2}OH, as a class of molecules formed readily from SO_{3} + RCOOH in the gas phase and which, therefore, may be of significance in the nucleation and growth of atmospheric aerosol particles.

  5. Estudo da capacidade de complexação de íons Cu2+ em solução aquosa usando celulose modificada com anidrido succínico e com poliaminas Study of copper removal from aqueous solutions using modified celluloses with succinic anhydride and polyamines

    Directory of Open Access Journals (Sweden)

    Gabriela S. Corti

    2004-12-01

    Full Text Available Nesse trabalho foi realizada a preparação de novos materiais, a partir da celulose, para complexar íons de metais pesados em solução aquosa e assim, descontaminar águas poluídas por tais metais. Na primeira parte foi realizada a modificação química da celulose usando o anidrido succínico. As funções carboxílicas introduzidas no material foram usadas para ancorar poliaminas produzindo-se três celuloses modificadas inéditas. Todos os materiais obtidos foram caracterizados por espectroscopia no infravermelho (IV e submetidos à análise elementar. A segunda parte do trabalho foi constituída da avaliação do poder de adsorção das celuloses modificadas obtidas em relação aos íons Cu2+ em solução aquosa. O estudo foi realizado usando a titulometria, um método analítico tradicional. Os vários materiais mostraram uma capacidade máxima de complexação variando entre 141 e 263 mg de Cu2+ por grama do material modificado. A eficiência na complexação dos íons Cu2+ mostrou-se proporcional ao número de funções aminas introduzidas na celulose.This work describes the preparation of new materials, derived from cellulose, to be used as complexing agents for heavy metal ions in aqueous solutions and, hence, to decontaminate waters polluted by such metals. The first part deals with the chemical modification of the cellulose using succinic anhydride. The carboxylic acid functions introduced in the material were used to anchor polyamines resulting in three novel modified celluloses. The materials obtained were characterized by elemental analysis and infrared spectroscopy (IR. The second part of the work features the evaluation of the adsorption capacity of the modified celluloses in relation to Cu2+ ions in aqueous solutions. The study was accomplished by titration, a traditional analytical method. The various materials showed a maximum complexing capacity ranging from 141 to 263 mg of Cu2+ per gram of the modified material. The

  6. CHARACTERIZATION AND THERMAL STABILITY OF PMR POLYIMIDES USING 7-OXA-BICYCLO[2,2,1]HEPT-5-ENE-2, 3-DICARBOXYLIC ANHYDRIDE AS END CAPS

    Institute of Scientific and Technical Information of China (English)

    Chen-liang Gong; Yan-feng Li; Hai-xia Yang; Xiao-long Wang; Shu-jiang Zhang; Shi-yong Yanga

    2011-01-01

    An anhydride monomer containing ether oxide bridge,7-oxa-bicyclo[2,2,1]hept-5-ene-2,3-dicarboxylic anhydride (ONA),was successfully synthesized by Diels-Alder reaction of furan and maleic anhydride.The ONA was also studied as an end-cap for the polymerization of monomer reactant (PMR) type polyimides.Three molecular weight levels of the ONA end-capped PMR resins were evaluated.The effects of process conditions of these novel PMR resins on thermal and mechanical properties were investigated.It was demonstrated that the imidized prepolymers using the end-cap have good processability,and the cured polyimide specimens exhibited good thermal stability.The initial decomposition temperature,Td (ca.580℃) and glass transition temperature,Tg (330℃) of the novel resin (PI-20),prepared under optimum process conditions,compare favorably with the Td (ca.620℃) and Tg (ca.348℃) of the state-of-the-art resin (PI'-20),respectively.

  7. Microwave synthesis and thermal properties of polyacrylate derivatives containing itaconic anhydride moieties

    Directory of Open Access Journals (Sweden)

    Osman Sameh M

    2012-08-01

    Full Text Available Abstract Background Microwave irradiation as an alternative heat source is now a well-known method in synthetic chemistry. Microwave heating has emerged as a powerful technique to promote a variety of chemical reactions, offering reduced pollution, low cost and offer high yields together with simplicity in processing and handling. On the other hand, copolymers containing both hydrophilic and hydrophobic segments are drawing considerable attention because of their possible use in biological systems. Various copolymer compositions can produce a very large number of different arrangements, producing materials of varying chemical and physical properties. Thus, the hydrophilicity of copolymers can be modified by changing the amount of incorporated itaconic anhydride. Results A series of methyl methacrylate (MMA and acrylamide (AA copolymers containing itaconic anhydride (ITA were synthesized by microwave irradiation employing a multimode reactor (Synthos 3000 Aton Paar, GmbH, 1400 W maximum magnetron as well as conventional method. The thermal properties of the copolymers were evaluated by different techniques. Structure-thermal property correlation based on changing the itaconic anhydride ratio was demonstrated. Results revealed that the incorporation of itaconic anhydride into the polymeric backbone of all series affect the thermal stability of copolymers. In addition, the use of the microwave method offers high molecular weight copolymers which lead eventually to an increase in thermal stability. Conclusions Microwave irradiation method showed advantages for the produced copolymers compared to that prepared by conventional method, where it can offer a copolymer in short time, high yield, more pure compounds and more thermally stable copolymers, rather than conventional method. Also, microwave irradiation method gives higher molecular weight due to prevention of the chain transfer. Moreover, as the itaconic anhydride content increases the thermal

  8. 桐油改性双环戊二烯不饱和树脂的合成研究%Study on the synthesis of tung oil modified dicyclopentadiene unsaturated polyester resin

    Institute of Scientific and Technical Information of China (English)

    崔竞方; 谭卫红; 刘承果; 周永红

    2013-01-01

    利用缩聚反应后期桐油与双环戊二烯不饱和聚酯(DCPD-UPR)主链上不饱和双键的Diels-Alder(D-A)反应合成了桐油改性DCPD-UPR,研究了各种原料用量对桐油改性DCPD-UPR其浇注体力学性能的影响.结果表明:当顺酐与苯酐的物质的量比为2∶1 ~3∶1,双环戊二烯与顺酐物质的量比为0.6~0.8∶1,1,2-丙二醇与二甘醇物质的量比2∶1,缩聚反应后期加入10%(质量分数)桐油,苯乙烯质量分数为35%~40%时,获得的桐油改性DCPD-UPR粘度适中,浇注体的断裂伸长率提高了78.2%,冲击强度提高了82.0%.%The tung oil modified dicyclopentadiene unsaturated polyester resin (DCPD -UPR) was synthesized by the Diels - Alder (D - A) reaction between tung oil and the double bond of DCPD - UPR main chain in the later stage of polycondensation. The effects of various raw material dosages on the mechanical properties of UPRs and their castings were investigated. The results showed that the tung oil modified DCPD - UPR with moderate viscosity was obtained as the conditions as followed: molar ratio of maleic anhydride to phthalic anhydride , DCPD to maleic anhydride and 1,2- propanediol to diethylene glycol 2-3:1,0. 6-0. 8:1 and 2:1, respectively, adding 10% tung oil in the late polycondensation and mass fraction of styrene 35% -40%. The elongation at break and impact strength of the castings were increased by 78. 2% and 82. 0% , respectively.

  9. Comparison of pH-sensitive degradability of maleic acid amide derivatives.

    Science.gov (United States)

    Kang, Sunyoung; Kim, Youngeun; Song, Youngjun; Choi, Jin Uk; Park, Euddeum; Choi, Wonmin; Park, Jeongseon; Lee, Yan

    2014-05-15

    We synthesized five maleic acid amide derivatives (maleic, citraconic, cis-aconitic, 2-(2'-carboxyethyl) maleic, 1-methyl-2-(2'-carboxyethyl) maleic acid amide), and compared their degradability for the future development of pH-sensitive biomaterials with tailored kinetics of the release of drugs, the change of charge density, and the degradation of scaffolds. The degradation kinetics was highly dependent upon the substituents on the cis-double bond. Among the maleic acid amide derivatives, 2-(2'-carboxyethyl) maleic acid amide with one carboxyethyl and one hydrogen substituent showed appropriate degradability at weakly acidic pH, and the additional carboxyl group can be used as a pH-sensitive linker.

  10. Synthesis of the Biomimetic Polymer: Aliphatic Diamine and RGDS Modified Poly(d,l-lactic acid)

    Institute of Scientific and Technical Information of China (English)

    Xu Feng NIU; Yuan Liang WANG; Yan Feng LUO; Jun PAN; Juan Fang SHANG; Li Xia GUO

    2005-01-01

    A novel poly(d,l-lactic acid) (PDLLA) based biomimetic polymer was synthesized by grafting maleic anhydride, butanediamine and arg-gly-asp-ser (RGDS) peptides onto the backbone of PDLLA, aiming to overcome the acidity and auto-accelerating degradation of PDLLA during degradation and to improve its biospecificity and biocompatibility. The synthetic copolymer was characterized by FTIR, 13C NMR and amino acid analyzer (AAA).

  11. Preparation and characterisation of acrylamide/maleic acid hydrogel

    Directory of Open Access Journals (Sweden)

    Klinpituksa, P.

    2005-09-01

    Full Text Available Acrylamide/maleic acid hydrogel, a superabsorbent polymer, was prepared by free radical polymerization in aqueous solution of acrylamide (AAm and maleic acid (MA : monomer and comonomer, respectively. Potassium persulfate and N,N,N’,N’-tetramethylethylenediamine were used as an initiator system. Also, ethylene glycol dimethacrylate (EGDMA and N,N’-methylenebisacrylamide (MBA were used as crosslinkers. Different compositions of acrylamide, maleic acid and crosslinkers were employed. Water swelling, equilibrium water content and swelling power of the hydrogel formed were determined. The result showed that the swelling in water at equilibrium of hydrogels was in the range of 8,420-10,300% and 3,160- 3,560%, equilibrium water content was in the range of 0.9880-0.9902 and 0.9630-0.9727 and swelling power was in the range of 84-103 and 31-36 using 1%EGDMA and 1%MBA as crosslinkers, respectively. The diffusion of water into hydrogel followed non-Fickian character based on swelling power.

  12. Inorganic-organic hybrid polymer electrolyte based on polysiloxane/poly(maleic imide-co-styrene) network

    Energy Technology Data Exchange (ETDEWEB)

    Kuo, P.-L.; Jheng, W.-H.; Chen, W.-F. [Department of Chemical Engineering, National Cheng Kung University, Tainan City 70101 (China); Liang, W.-J. [Fire Protection and Safety Research Center, National Cheng Kung University, Tainan City (China)

    2010-10-01

    Covalently cross-linked nonfluorinated hydrocarbon ionomers are synthesized by introducing sulfonate groups and a siloxane cross-linker through thermally and chemically stable imide bonding on poly(styrene-co-maleic anhydride). The three-dimensional polysiloxane framework, which does not only act as a robust scaffold but also provide sites for the hydrogen bonding with water, contribute to the increase in bound water degree, higher proton conductivity at lower ion exchange capacity, and greatly decreased methanol permeability. The spherical-shaped ionic clusters produce a comparable proton conductivity (10{sup -1} S cm{sup -1} above 60 C) to Nafion-117. The conductivity of the hybrid ionomer does not decrease to gain its selectivity, but instead increased. Methanol permeability is {proportional_to}70% lower than that of Nafion-117, but has a higher water uptake and IEC. The membrane with IEC values of 1.1 mequiv. g{sup -1} exhibits a constant conductivity for 200 h in hydrolytic stability test, and produce a power density 20% higher than Nafion-117 in single DMFC operation. (author)

  13. 烯基琥珀酸酐改性瓜尔胶的合成及其凝胶破胶性能研究%Synthesis and Property Study of Gel and Gel Breaking for Guar Gum Modified by Alkenyl Succinic Anhydride

    Institute of Scientific and Technical Information of China (English)

    薛贝; 沈一丁; 杨晓武; 李培枝; 王健

    2012-01-01

    A novel guar gum modified by alkenyl succinic anhydride (ASA) was synthesized by dry preparation method when the catalyst was NaHCO3. The optimum reaction condition of the gum was obtained as follows: guar gum and ASA in mass ratio 7:1, 60℃ reaction temperature, 10 hrs reaction time and 0.4% NaHCO3dosage. The surface tension of 0.4% modified guar gum solution was of 35.29 raN/m, and that of the gelout solution, which was broken by ammonium persulfate, was of 29.65 mN/m. The interf~ial tension of gelout solution and kerosene was of 2.27 raN/m, and the residue content was of 300 mg/L. It was showed that the properties of temperature and shear resistance were improved after the guar gum modified. When the shearing rate or temperature was low, the viscosity of modified gum decreased, which was beneficial to reduce the flowing friction of fluid in pipeline. On the contrary, when the shearing rate or temperature was high, the viscosity increased, which was conducive to bring sand fracturing in later process.%以碳酸氢钠为催化剂,采用干法制备烯基琥珀酸酐(ASA)改性瓜尔胶。瓜尔胶与ASA反应的最佳条件为:瓜尔胶原粉、ASA质量比7:1,反应温度60℃,反应时间10h,碳酸氢钠质量分数0.4%。0.4%的ASA改性瓜尔胶水溶液的表面张力为35.29mN/m。用过硫酸铵破胶后破胶液的表面张力为29.65mN/m,煤油/冻胶破胶液的界面张力为2.27mN/m,残渣含量为300mg/L。与瓜尔胶原粉相比,改性瓜尔胶制备冻胶的耐温性、耐剪切性提高。在低剪切速率或温度较低时,改性瓜尔胶黏度降低,有利于减少流体在管道中流动的摩阻;而在高剪切速率或温度较高时,改性瓜尔胶黏度增加,有利于后期的携沙造缝。图8表1参13

  14. Exposure to cyclic anhydrides in welding: a new allergen-chlorendic anhydride.

    Science.gov (United States)

    Pfäffli, Pirkko; Hämeilä, Mervi; Keskinen, Helena; Wirmoila, Ritva

    2002-11-01

    Respiratory effects associated with welding fumes have been manifested in welders as occupational asthma. Previous studies have concerned mainly the effects of metal fume exposure, although it has also been suggested that asthma may develop as a result of exposure to contaminants generated from painted metals. To determine whether welding fumes contain irritating and sensitizing anhydrides, air samples were collected during the repair welding of forest harvesters, which were painted with chlorinated polyester paint. Samples were collected with an assembly of a spiral glass trap inserted between a filter holder with a Teflon filter and a Tenax sampling tube. Sample analyses were with GC-MS and GC-ECD. Sensitizing anhydrides released from the paint into the air were primarily chlorendic anhydride (paint films are electrical insulators, the film around the welding seam was removed before arc welding. Removal of paint with an abrasive wheel caused the least exposure to HCl (paint coating be removed from an area around the seam with an abrasive wheel, not by burning, before welding.

  15. Research on the Preparation and Performance of Binary Modified Maltodextrin Water-Reducing Agent

    Directory of Open Access Journals (Sweden)

    Jingzhi Wu

    2016-01-01

    Full Text Available Using maltodextrin (MD of different dextrose equivalent (DE values, 1,3-propanesultone, and maleic anhydride as raw materials, a novel binary modified maltodextrin (BMMD was synthesized and further applied as a water-reducing agent. Its structure was characterized by Fourier transform infrared (FT-IR and UV. The rheological behavior of the sample solution and strengths for concrete were also determined and the adsorption was tested by TOC. The influence of the process parameters to degree of substitution (DS and the dosage on the fluidity of cement paste were investigated. The results show that the optimal conditions of sulfonation were the MD of DE 15, m (sulfonated agent/m (MD of 1.4, the catalyst amount of 1% by mass MD, and the reaction time of 12 h; the optimal conditions of esterification were m (esterified agent/m (SMD of 0.6, the reaction temperature of 90°C, and the reaction time of 4 h. The optimal dosages of sulfonated maltodextrin (SMD and BMMD were 0.475% and 0.45%, respectively. In this dosage, the main dispersion capacity of BMMD attributes to two kinds of anchoring groups (SO3-  &  COO- and the appropriate molecular weight of MD.

  16. Anhydride formation is not a valid mechanism for peptide cleavage by carboxypeptidase-A: a semiempirical reaction pathway study

    Science.gov (United States)

    Vardi-Kilshtain, Alexandra; Shoham, Gil; Goldblum, Amiram

    The mechanism of action of zinc metalloproteinases has been studied by following the direct nucleophilic pathway, which has been frequently suggested but not yet examined by computational methods, and comparing it to other pathways. We computed the reaction enthalpies for the direct nucleophilic attack by Glu270 in the active site model of carboxypeptidase-A on a model substrate's peptide carbonyl and followed this pathway through mixed anhydride formation and subsequent anhydride cleavage by water. The starting molecular coordinates originate in our own high-resolution crystal structure and the computations have been conducted with the minimal neglect of differential overlap (MNDO) Hamiltonian, modified to include the d-orbitals of zinc and the effects of multiple hydrogen bonding, thus labelled MNDO/d/H. Compared to our recent results for two other candidate pathways for this mechanism, both of the General-Acid-General-Base type, we conclude that the direct nucleophilic or 'anhydride' pathway has a much higher energy barrier at the rate determining step, which is a proton transfer, than previously calculated paths. We argue that the 'anhydride' pathway is thus not a valid one for the cleavage of peptides by carboxypeptidase-A.

  17. Maleic acid treatment of biologically detoxified corn stover liquor.

    Science.gov (United States)

    Kim, Daehwan; Ximenes, Eduardo A; Nichols, Nancy N; Cao, Guangli; Frazer, Sarah E; Ladisch, Michael R

    2016-09-01

    Elimination of microbial and enzyme inhibitors from pretreated lignocellulose is critical for effective cellulose conversion and yeast fermentation of liquid hot water (LHW) pretreated corn stover. In this study, xylan oligomers were hydrolyzed using either maleic acid or hemicellulases, and other soluble inhibitors were eliminated by biological detoxification. Corn stover at 20% (w/v) solids was LHW pretreated LHW (severity factor: 4.3). The 20% solids (w/v) pretreated corn stover derived liquor was recovered and biologically detoxified using the fungus Coniochaeta ligniaria NRRL30616. After maleic acid treatment, and using 5 filter paper units of cellulase/g glucan (8.3mg protein/g glucan), 73% higher cellulose conversion from corn stover was obtained for biodetoxified samples compared to undetoxified samples. This corresponded to 87% cellulose to glucose conversion. Ethanol production by yeast of pretreated corn stover solids hydrolysate was 1.4 times higher than undetoxified samples, with a reduction of 3h in the fermentation lag phase.

  18. Characterization of differently sized granule fractions of yellow pea, cowpea and chickpea starches after modification with acetic anhydride and vinyl acetate

    NARCIS (Netherlands)

    Huang, J.; Schols, H.A.; Jin, Z.; Sulmann, E.; Voragen, A.G.J.

    2007-01-01

    The effect of reagent type on the properties of acetylated starches was studied for yellow pea, cowpea and chickpea starches after modification with acetic anhydride and vinyl acetate. Samples modified with vinyl acetate showed higher swelling volume and peak viscosity than those acetylated with

  19. Characterization of differently sized granule fractions of yellow pea, cowpea and chickpea starches after modification with acetic anhydride and vinyl acetate

    NARCIS (Netherlands)

    Huang, J.; Schols, H.A.; Jin, Z.; Sulmann, E.; Voragen, A.G.J.

    2007-01-01

    The effect of reagent type on the properties of acetylated starches was studied for yellow pea, cowpea and chickpea starches after modification with acetic anhydride and vinyl acetate. Samples modified with vinyl acetate showed higher swelling volume and peak viscosity than those acetylated with ace

  20. Utilization of α-olefins obtained by pyrolysis of waste high density polyethylene to synthesize α-olefin-succinic-anhydride based cold flow improvers

    Institute of Scientific and Technical Information of China (English)

    Norbert MISKOLCZI; Richard SAGI; László BARTHA; Lívia FORCEK

    2009-01-01

    A new route of utilization of α-olefin rich hydrocarbon fractions obtained by waste polymer pyrolysis was investigated. α-olefin-succinic-anhydride intermediate-based pour point depressant additives for diesel fuel were synthesized, in which reactions needed α-olefins were obtained by pyrolysis of waste high-density polyethylene (HDPE). Fraction of α-olefins was produced by the de-polymerization of plastic waste in a tube reactor at 500℃ in the absence of catalysts and air. C17~22 range of mixtures of olefins and paraffins were separated for synthesis and then, these hydrocarbons were reacted with maleic-anhydride (MA) for formation of α-olefin-succinic-anhydride intermediates. The olefin-rich hydrocarbon fraction contained approximately 60% of olefins, including 90%~95% α-olefins. Other intermediates were produced in the same way by using commercial C20 α-olefin instead of C17~22 olefin mixture. The two different experimental intermediates with number average molecular weights of 1850g/mol and 1760g/mol were reacted with different alcohols: 1-butanol, 1-hexanol, 1-octanol, i-butanol, and c-hexanol to produce their ester derivatives. The synthesized ten experimental pour point depressants were added in different concentrations to conventional diesel fuel, which had no other additive content before. The structure and efficiency of experimental additives were followed by different standardized and non-standardized methods. Results showed that the experimental additives on the basis of the product of waste pyrolysis were able to decrease not only the pour but also the cloud point and cold filter plugging point (CFPP) of diesel fuel, whose effects could be observed even if the concentration of additives was low. Furthermore, all additives had anti-wear and anti-friction effects in diesel fuel.

  1. XRD study of intercalation in statically annealed composites of ethylene copolymers and organically modified montmorillonites. 2. One-tailed organoclays

    Directory of Open Access Journals (Sweden)

    Sara Filippi

    2014-01-01

    Full Text Available Ethylene copolymers with different polar comonomers, such as vinyl acetate, methyl acrylate, glycidyl methacrylate, and maleic anhydride, were used for the preparation of polymer/clay nanocomposites by statically annealing their mechanical mixtures with different commercial or home-made organically modified montmorillonites containing only one long alkyl tail. The nanostructure of the products was monitored by X-ray diffraction, and the dispersion of the silicate particles within the polymer matrix was qualitatively evaluated through microscopic analyses. The effect of the preparation conditions on the structure and the morphology of the composites was also addressed through the characterization of selected samples with similar composition prepared by melt compounding. In agreement with the findings reported in a previous paper for the composites filled with two-tailed organoclays, intercalation of the copolymer chains within the tighter galleries of the one-tailed clays occurs easily, independent of the application of a mechanical stress. However, the shear-driven break-up of the intercalated clay particles into smaller platelets (exfoliation seems more hindered. A collapse of the organoclay interlayer spacing was only observed clearly for a commercial one-tailed organoclay – Cloisite® 30B – whereas the same effect was almost negligible for a home-made organoclay with similar structure.

  2. Hydration of AN Acid Anhydride: the Water Complex of Acetic Sulfuric Anhydride

    Science.gov (United States)

    Smith, CJ; Huff, Anna; Mackenzie, Becca; Leopold, Ken

    2017-06-01

    The water complex of acetic sulfuric anhydride (ASA, CH_{3}COOSO_{2}OH) has been observed by pulsed nozzle Fourier transform microwave spectroscopy. ASA is formed in situ in the supersonic jet via the reaction of SO_{3} and acetic acid and subsequently forms a complex with water during the expansion. Spectra of the parent and fully deuterated form, as well as those of the species derived from CH_{3}^{13}COOH, have been observed. The fitted internal rotation barrier of the methyl group is 219.599(21), \\wn indicating the complexation with water lowers the internal rotation barrier of the methyl group by 9% relative to that of free ASA. The observed species is one of several isomers identified theoretically in which the water inserts into the intramolecular hydrogen bond of the ASA. Aspects of the intermolecular potential energy surface are discussed.

  3. Method for epoxy foam production using a liquid anhydride

    Science.gov (United States)

    Celina, Mathias [Albuquerque, NM

    2012-06-05

    An epoxy resin mixture with at least one epoxy resin of between approximately 50 wt % and 100 wt %, an anhydride cure agent of between approximately 0 wt % and approximately 50 wt %, a tert-butoxycarbonyl anhydride foaming agent of between proximately 0.1-20 wt %, a surfactant and an imidazole or similar catalyst of less than approximately 2 wt %, where the resin mixture is formed from at least one epoxy resin with a 1-10 wt % tert-butoxycarbonyl anhydride compound and an imidazole catalyst at a temperature sufficient to keep the resin in a suitable viscosity range, the resin mixture reacting to form a foaming resin which in the presence of an epoxy curative can then be cured at a temperature greater than 50.degree. C. to form an epoxy foam.

  4. Poly(methyl vinyl ether-alt-maleic acid)-functionalized porous silicon nanoparticles for enhanced stability and cellular internalization.

    Science.gov (United States)

    Shahbazi, Mohammad-Ali; Almeida, Patrick V; Mäkilä, Ermei; Correia, Alexandra; Ferreira, Mónica P A; Kaasalainen, Martti; Salonen, Jarno; Hirvonen, Jouni; Santos, Hélder A

    2014-03-01

    Currently, developing a stable nanocarrier with high cellular internalization and low toxicity is a key bottleneck in nanomedicine. Here, we have developed a successful method to covalently conjugate poly(methyl vinyl ether-co-maleic acid) (PMVE-MA) copolymer on the surface of (3-aminopropyl)triethoxysilane-functionalized thermally carbonized porous silicon nanoparticles (APSTCPSi NPs), forming a surface negatively charged nanovehicle with unique properties. This polymer conjugated NPs could modify surface smoothness, charge, and hydrophilicity of the developed NPs, leading to considerable improvement in the colloidal and plasma stabilities via enhanced suspensibility and charge repulsion. Furthermore, despite the surface negative charge of the polymer-conjugated NPs, the cellular internalization was increased in both MDA-MB-231 and MCF-7 breast cancer cells. These results provide a proof-of-concept evidence that such polymer-based PSi nanocomposite can be extensively used as a promising candidate for intracellular drug delivery.

  5. Preparation and Characterization of Sulfonic Acid Functionalized Silica and Its Application for the Esterification of Ethanol and Maleic Acid

    Science.gov (United States)

    Sirsam, Rajkumar; Usmani, Ghayas

    2016-04-01

    The surface of commercially available silica gel, 60-200 mesh size, was modified with sulfonic acid through surface activation, grafting of 3-Mercaptopropyltrimethoxysilane, oxidation and acidification of 3-Mercaptopropylsilica. Sulfonic Acid Functionalization of Silica (SAFS) was confirmed by Fourier Transform Infra-red (FTIR) spectroscopy and thermal gravimetric analysis. Acid-base titration was used to estimate the cation exchange capacity of the SAFS. Catalytic activity of SAFS was judged for the esterification of ethanol with maleic acid. An effect of different process parameters viz. molar ratio, catalyst loading, speed of agitation and temperature were studied and optimized by Box Behnken Design (BBD) of Response Surface Methodology (RSM). Quadratic model developed by BBD-RSM reasonably satisfied an experimental and predicted values with correlation coefficient value R2 = 0.9504.

  6. Characterization and in vitro degradation of salicylate-derived poly(anhydride-ester microspheres).

    Science.gov (United States)

    Yeagy, Brian A; Prudencio, Almudena; Schmeltzer, Robert C; Uhrich, Kathryn E; Cook, Thomas J

    2006-09-01

    The aim of this study was to investigate how glass transition temperature (Tg) influenced polymer microsphere formation and degradation of three chemically, similar novel salicylatebased poly(anhydride-esters): poly[1,6-bis(o-carboxyphenoxy)hexanoate] (CPH), Tg = 59 degrees C; poly[1,8-bis(o-carboxyphenoxy)octanoate] (CPO), Tg = 30 degrees C; and poly[1,10-bis(ocarboxyphenoxy) decanoate] (CPD), Tg = 27 degrees C. Microspheres of these polymers were prepared using a modified oil-in-water solvent evaporation method and processed by either resuspension or washed by centrifugation. The morphology of the microspheres determined by scanning electron microscopy (SEM) revealed that an extra washing step appears to increase aggregation as the Tg decreases; whereas only limited aggregation occurred in the polymer with the lowest Tg, CPD, in those not washed by centrifugation. Residual polyvinyl alcohol apparently affected the drug release rates from the microspheres by a stabilization process that produced an 8 h lag time and a 5% decrease in the amount of drug released over a 7 day period compared to microspheres washed free of PVA. These results demonstrate that salicylate-based poly(anhydride-esters) with sufficiently high Tgs, can be processed into microspheres that release salicylate over a time period amenable for drug delivery applications.

  7. Mechanical Force Induced Functionalization of High Density Polyethylene with Maleic Anhydride%机械力引发马来酸酐官能化PE-HD研究

    Institute of Scientific and Technical Information of China (English)

    韩颖; 张云灿

    2005-01-01

    采用机械力引发方法研究了马来酸酐(MAH)熔融接枝高密度聚乙烯(PE-HD)的官能化反应,并考察了接枝产物对PE-HD/PA66及PE-HD/GF材料力学性能的影响.结果表明:通过控制引发剂含量和提高双螺杆挤出机的螺杆转速可抑制PE-HD在接枝过程中的交联副反应,制得具有较高接枝率(Gd=0.75~1.34%),较好熔体流动性(0.3~0.6 g/10 min)和较低凝胶含量(≤0.9%)的接枝产物;该方法所得产物可使PE-HD/PA66共混材料的缺口冲击强度提高至6.5倍以上,使PE-HD/GF复合材料的拉伸、弯曲和缺口冲击强度显著增大.

  8. Effect of using batch or semi-batch reactor on the chemical composition distribution of styrene-maleic anhydride-acrylonitrile terpolymers

    OpenAIRE

    Cunha, Regina de J. S.; Ailton S. Gomes

    1997-01-01

    Texto completo: acesso restrito. p.595-600 The influence of the reactor type on distribution of chemical composition of STY AN/MA terpolymers obtained by free-radical polymerization is shown. When a batch reactor was used we have obtained polymers with broad chemical composition distribution. However, if a semi-batch reactor with appropriate addition protocol was used it can be possible to synthesize terpolymers with homogeneous chemical composition.

  9. Dynamic mechanical analysis of binary and ternary polymer blends based on nylon copolymer/EPDM rubber and EPM grafted maleic anhydride compatibilizer

    Directory of Open Access Journals (Sweden)

    2007-10-01

    Full Text Available The dynamic mechanical properties such as storage modulus, loss modulus and damping properties of blends of nylon copolymer (PA6,66 with ethylene propylene diene (EPDM rubber was investigated with special reference to the effect of blend ratio and compatibilisation over a temperature range –100°C to 150°C at different frequencies. The effect of change in the composition of the polymer blends on tanδ was studied to understand the extent of polymer miscibility and damping characteristics. The loss tangent curve of the blends exhibited two transition peaks, corresponding to the glass transition temperature (Tg of individual components indicating incompatibility of the blend systems. The morphology of the blends has been examined by using scanning electron microscopy. The Arrhenius relationship was used to calculate the activation energy for the glass transition of the blends. Finally, attempts have been made to compare the experimental data with theoretical models.

  10. 氯化聚乙烯接枝马来酸酐胶粘剂的研究%Study on Chlorinated Polyethylene Graft Maleic Anhydride Adhesive

    Institute of Scientific and Technical Information of China (English)

    邢方亮; 白洪才; 边兴海

    2002-01-01

    本文介绍了改性聚丙烯(PP)基泡沫材料用的水溶性胶粘剂的研制.该胶粘剂不影响泡沫材料的阻燃性能和吸声性能,并有较好的热稳定性和储存性以及优化的耐水性.

  11. Characterization of polyethylene wax grafted with maleic anhydride by solution method%溶液法聚乙烯蜡接枝马来酸酐的表征

    Institute of Scientific and Technical Information of China (English)

    朱德钦; 王剑峰; 张丽珍; 林铭前; 林增祥; 王碧玮

    2007-01-01

    以溶液法合成了聚乙烯蜡接枝马来酸酐(PEW-g-MAH).利用酸碱中和滴定法测定PEW-g-MAH中酸酐含量,借助红外光谱分析证明接枝物的存在,探讨了取样量、滴定温度对测试结果的影响,得到表征PEW-g-MAH的优化实验方法.结果表明,在温度70℃下取样量达到1.5g-2g时,能得到较稳定的接枝率测试数据.

  12. Maleic anhydride grafted chlorinated polyethylene by melt blending%马来酸酐熔融接枝氯化聚乙烯

    Institute of Scientific and Technical Information of China (English)

    陈尔凡; 李中浩; 马驰; 吴波; 裴群

    2015-01-01

    以过氧化二异丙苯、过氧化二苯甲酰、偶氮二异丁腈为引发剂,研究了引发剂及马来酸酐用量对熔融接枝氯化聚乙烯的接枝率、硫化工艺性及力学性能的影响,并用红外光谱表征研究了接枝结构及机理.制备了马来酸酐接枝氯化聚乙烯/聚乙烯共混物,通过共混物的性能考察了马来酸酐接枝氯化聚乙烯的自黏性,并采用差示扫描量热法、热重分析法和扫描电镜对共混物进行了热行为和形态的分析.结果表明,过氧化二苯甲酰引发马来酸酐接枝氯化聚乙烯的效果较好,组分最优配伍时(过氧化二苯甲酰1.6份,马来酸酐8份)接枝物的硫化工艺性、力学性能和热性能明显改善,硫化出现了典型的平坦区,拉伸强度达到16.7 MPa.共混物的力学性能和耐热性能均有所提高,接枝后氯化聚乙烯的自黏性有较大程度的改善.

  13. 苯乙烯/马来酸酐接枝聚乙烯蜡的研究%Research of maleic anhydride and styrene grafted polyethylene wax

    Institute of Scientific and Technical Information of China (English)

    黄军左; 李道通; 李国远

    2009-01-01

    用溶液法制备了马来酸酐和马来酸酐/苯乙烯双单体接枝的聚乙烯蜡,考察了反应时间、温度、引发荆、单体用量对产物接枝率的影响.结果表明二叔丁基过氧化物是一种优良的接枝反应引发剂,在ω(引发剂)=0.4%、ω(马来酸酐)=6.0%、ω(苯乙烯)=4.0%、反应温度143℃、反应时间2.5 h的条件下,聚乙烯蜡接枝率为3.4%.并对产品进行了红外光谱分析、热分析表征.

  14. Study on maleic anhydride grafted low molecular weight polyethylene%低分子量聚乙烯熔融接枝马来酸酐的研究

    Institute of Scientific and Technical Information of China (English)

    王洪梅; 张海霞; 郝立辉; 沈立新; 张振林

    2008-01-01

    研究了吉林石化高密度聚乙烯装置副产低分子量聚乙烯与马来酸酐(MAH)的融熔接枝反应,考察了单体、引发剂用量、反应时间、温度对接枝率的影响.马来酸酐接枝低分子量聚乙烯应用于PE/CaCO3体系的性能测试结果表明,接枝物可以起到偶联剂的作用,改善体系的性能.

  15. Solid-Phase Grafting of Maleic Anhydride onto Polyethylene%聚乙烯和顺丁烯二酸酐的固相接枝共聚

    Institute of Scientific and Technical Information of China (English)

    周立庆; 沈宁祥; 刘国友; 刘超

    2000-01-01

    采用固相接枝共聚法在聚乙烯大分子链上接枝顺丁烯二酸酐,研究了其表面的极性和结晶行为参数.固相接枝反应的接枝率与单体浓度和引发剂浓度有关,当反应温度为105℃,反应时间为2h,单体和引发剂的质量分数均为8%左右时,接枝率最大.接枝物的Tm、Tc、△Hm和△Hc值均比聚乙烯低.

  16. Two novel R- and S-malato-bridged coordination polymers by reacting lanthanide chloride and maleic anhydride, 1,10-phenanthroline at hydrothermal condition

    Science.gov (United States)

    Zhang, Li-Ping; Huang, Liang; Qu, Ling-bo; Peng, Hua; Zhao, Yu-Fen

    2006-04-01

    Two less common lanthanide coordination polymers, [Ln 2(fum)(malate) 2(phen) 2] n· n1.25H 2O (Ln=Eu, 1; Pr, 2. fum=fumarate, phen=1,10-phenanthroline) were synthesized and characterized by IR spectra and X-ray crystallography. Single crystal X-ray diffraction analysis shows that complex 1 is isostructural with complex 2. In the two complexes, we found a pair of enantiomers ( R-malate and S-malate) which are obtained by addition reaction between maleate and water and fumarate which result from configurational tranformation of maleate. The two structures consist of coordination polymer chains along the c-axis which are held together solely through hydrogen bonding and π-π stacking. Three-dimension supramolecular structures are formed through the two types of weak interaction. The IR data are also described and compared with those of other similar complexes.

  17. Promotional Effect of Bismuth as Dopant in Bi-Doped Vanadyl Pyrophosphate Catalysts for Selective Oxidation of n-Butane to Maleic Anhydride

    Institute of Scientific and Technical Information of China (English)

    Y.H.Taufiq-Yap; Y.Kamiya; K.P.Tan

    2006-01-01

    Bismuth-promoted (1% and 3%) vanadyl pyrophosphate catalysts were prepared by refluxing creased the surface area and lowered the overall V oxidation state. Profiles of temperature programmed reduction (TPR) in H2 show a significant shift of the maxima of major reduction peaks to lower temperatures for the Bi-promoted catalysts. A new peak was also observed at the low temperature region for the catalyst with 3% of Bi dopant. The addition of Bi also increased the total amount of oxygen removed from the catalysts. The reduction pattern and reactivity information provide fundamental insight into the catalytic properties of the catalysts. Bi-promoted catalysts were found to be highly active (71% and 81%conversion for 1% and 3% Bi promoted catalysts, respectively, at 703 K), as compared to the unpromoted material (47% conversion). The higher activity of the Bi-promoted catalysts is due to that these catalysts possess highly active and labile lattice oxygen. The better catalytic performance can also be attributed to the larger surface area.

  18. 聚烯烃接枝马来酸酐的反应挤出研究%STUDY ON REACTIVE EXTRUSION OF POLYOLEFIN GRAFTED MALEIC ANHYDRIDE

    Institute of Scientific and Technical Information of China (English)

    张广成

    2002-01-01

    研究了聚乙烯(PE)、聚丙烯(PP)接枝马来酸酐(MAH)的反应挤出,进行了反应体系的热分析,讨论了引发剂过氧化二异丙苯(DCP)对PE/DCP和PP/DCP体系的影响,以及DCP、MAH和电子给予体(EDA)对LDPE/DCP/MAH和PP/DCP/MAH两种接枝体系的影响.

  19. In vitro methane production and quality of corn silage treated with maleic acid

    Directory of Open Access Journals (Sweden)

    Kanber Kara

    2015-12-01

    Full Text Available This study aimed to determine the effects of maleic acid (MA addition to corn at ensiling on silage quality and in vitro methane and total gas production, metabolisable energy (ME, and organic matter digestibility (OMD parameters by using in vitro gas production techniques. Forage corn was ensiled either without (control group: MA 0 or with three different dosages of maleic acid, 0.5% (MA 0.5, 1.0% (MA 1.0, and 1.5% (MA 1.5 w/w of the fresh material for 60 days. As a result of this study, neutral detergent fibre level was decreased in the MA 1.5 group (P<0.05. The 0.5, 1.0, and 1.5% addition of maleic acid to forage corn at ensiling increased lactic acid concentration (P<0.05 in silage and reduced propionic acid (P<0.05. Iso-valeric acid concentration in the organic acids of the silage was decreased with maleic acid addition (P<0.05. The maleic acid addition decreased in vitro ruminal methane production (P<0.01. The silage pH value, and acetic, butyric and isobutyric acid concentrations and in vitro total gas production, OMD, and ME values did not change by MA addition (P>0.05. It was concluded that MA addition could reduce methane emission without any negative effects on silage nutrient composition or in vitro ruminal fermentation parameters.

  20. Substituted Phthalic Anhydrides from Biobased Furanics: A New Approach to Renewable Aromatics.

    Science.gov (United States)

    Thiyagarajan, Shanmugam; Genuino, Homer C; Śliwa, Michał; van der Waal, Jan C; de Jong, Ed; van Haveren, Jacco; Weckhuysen, Bert M; Bruijnincx, Pieter C A; van Es, Daan S

    2015-09-21

    A novel route for the production of renewable aromatic chemicals, particularly substituted phthalic acid anhydrides, is presented. The classical two-step approach to furanics-derived aromatics via Diels-Alder (DA) aromatization has been modified into a three-step procedure to address the general issue of the reversible nature of the intermediate DA addition step. The new sequence involves DA addition, followed by a mild hydrogenation step to obtain a stable oxanorbornane intermediate in high yield and purity. Subsequent one-pot, liquid-phase dehydration and dehydrogenation of the hydrogenated adduct using a physical mixture of acidic zeolites or resins in combination with metal on a carbon support then allows aromatization with yields as high as 84 % of total aromatics under relatively mild conditions. The mechanism of the final aromatization reaction step unexpectedly involves a lactone as primary intermediate.

  1. Microwave-assisted addition of azomethines to isatoic anhydride

    Indian Academy of Sciences (India)

    E Dominic Jacob; Lopez Mathew; Baby Thomas

    2007-01-01

    Diels-Alder addition of azomethines to isatoic anhydride in a solvent-free and eco-friendly condition is investigated using a microwave oven. The product is exclusively 2,3-diaryl-2,3-dihydroquinazolin-4(1H)-ones 4a-d. HOMO-LUMO energy of the iminoketene and the dienophiles were calculated using semi-empirical AM1 calculations.

  2. 21 CFR 872.3490 - Carboxymethylcellulose sodium and/or polyvinylmethylether maleic acid calcium-sodium double salt...

    Science.gov (United States)

    2010-04-01

    ... polyvinylmethylether maleic acid calcium-sodium double salt denture adhesive. 872.3490 Section 872.3490 Food and Drugs... DENTAL DEVICES Prosthetic Devices § 872.3490 Carboxymethylcellulose sodium and/or polyvinylmethylether maleic acid calcium-sodium double salt denture adhesive. (a) Identification. A carboxymethylcellulose...

  3. Thermal analysis of polypropylene modified by gamma irradiation composites under outdoor conditions

    Energy Technology Data Exchange (ETDEWEB)

    Komatsu, Luiz G.H.; Oliani, Washington L.; Lugao, Ademar B.; Parra, Duclerc F., E-mail: dfparra@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    This work reports the influence of the clay in the degradation process of the HMSPP.The polypropylene (PP) was irradiated under acetylene atmosphere in gamma irradiation source ({sup 60}Co) to obtain the HMSPP (high melt strength polypropylene). Composites of HMSPP were processed in twin-screw extruder with clay Cloisite 20A and Maleic Anhydride (PP-g-MA) as coupling agent. The obtained composites were exposed under outdoor conditions for 6 months. The ageing effects were characterized by Differential Scanning Calorimetry (DSC), Thermogravimetry Analysis (TGA). Chemical oxidation was evaluated by Carbonyl Index (IC) through infrared Spectroscopy (FT-IR). The results showed correlation between carbonyl index and ageing time. (author)

  4. Determination of maleic hydrazide residues in garlic bulbs by HPLC.

    Science.gov (United States)

    Mamani Moreno, Claudia; Stadler, Teodoro; da Silva, Antônio Alberto; Barbosa, Luiz C A; de Queiroz, Maria Eliana L R

    2012-01-30

    In recent years, the release of information about the preventative and curative properties of garlic on different diseases and their benefits to human health has led to an increase in the consumption of garlic. To meet the requirements of international markets and reach competitiveness and profitability, farmers seek to extend the offer period of fresh garlic by increasing post-harvest life. As a result, the use of maleic hydrazide (1,2-dihydropyridazine-3,6-dione) [MH], a plant growth regulator, has been widespread in various garlic growing regions of the world. The present work was undertaken to develop and validate a new analytical procedure based on MH extraction from garlic previously frozen by liquid nitrogen and submitted to low temperature clean-up. The applicability of the method by analysis of garlic samples from a commercial plantation was also demonstrated. The influence of certain factors on the performance of the analytical methodology were studied and optimized. The approach is an efficient extraction, clean-up and determination alternative for MH residue-quantification due to its specificity and sensitivity. The use of liquid nitrogen during the sample preparation prevents the degradation of the analyte due to oxidation reactions, a major limiting factor. Moreover, the method provides good linearity (r(2): 0.999), good intermediate precision (coefficient of variation (CV): 8.39%), and extracts were not affected by the matrix effect. Under optimized conditions, the limit of detection (LOD) (0.33 mg kg(-1)) was well below the maximum residue level (MRL) set internationally for garlic (15 mg kg(-1)), with excellent rates of recovery (over 95%), good repeatability and acceptable accuracy (CV averaged 5.74%), since garlic is a complex matrix. The analytical performance of the methodology presented was compared with other techniques already reported, with highly satisfactory results, lower LOD and higher recoveries rates. In addition, the extraction

  5. Acylation Modification of Antheraea pernyi Silk Fibroin Using Succinic Anhydride and Its Effects on Enzymatic Degradation Behavior

    Directory of Open Access Journals (Sweden)

    Xiufang Li

    2013-01-01

    Full Text Available The degradation rate of tissue engineering scaffolds should match the regeneration rate of new tissues. Controlling the degradation behavior of silk fibroin is an important subject for silk-based tissue engineering scaffolds. In this study, Antheraea pernyi silk fibroin was successfully modified with succinic anhydride and then characterized by zeta potential, ninhydrin method, and FTIR. In vitro, three-dimensional scaffolds prepared with modified silk fibroin were incubated in collagenase IA solution for 18 days to evaluate the impact of acylation on the degradation behavior. The results demonstrated that the degradation rate of modified silk fibroin scaffolds was more rapid than unmodified ones. The content of the β-sheet structure in silk fibroin obviously decreased after acylation, resulting in a high degradation rate. Above all, the degradation behavior of silk fibroin scaffolds could be regulated by acylation to match the requirements of various tissues regeneration.

  6. A facile and efficient synthetic method for 4-phenylethynylphthalic anhydride

    Institute of Scientific and Technical Information of China (English)

    Di Feng Wu; Mei Jia Yang; Yang Wang; Guo Wei Gao; Jian Men

    2011-01-01

    A novel approach to the synthesis of 4-phenylethynylphthalic anhydride has been described. The target compound was synthesized by Pd/Cu catalyzed Sonogashira coupling reaction between phenylacetylene and 4-bromophthalic acid which was for the first time employed as start material, followed by dehydration of 4-phenylethynylphthalic acid. Compared with traditional synthetic routes, this method provides several advantages such as readily available raw materials, convenient manipulation and high yield. The products were characterized by IR, 1H NMR, 13C NMR, MS and elemental analysis, respectively.

  7. TRIMELLITIC ANHYDRIDE-INDUCED EOSINOPHILIA IN A MURINE MODEL OF OCCUPATIONAL ASTHMA

    Science.gov (United States)

    TRIMELLITIC ANHYDRIDE-INDUCED EOSINOPHILIA IN A MURINE MODEL OF OCCUPATIONAL ASTHMA. J F Regal, ME Mohrman, E Boykin and D Sailstad. Dept. of Pharmacology, University of Minnesota, Duluth, MN, USA and NHEERL, ORD, US EPA, RTP, NC, USA.Trimellitic anhydride (TMA) is a small m...

  8. Investigations on organolead compounds III. The reaction of organolead compounds with ketene. (Triphenylplumbyl)acetic anhydride

    NARCIS (Netherlands)

    Willemsens, L.C.; Kerk, G.J.M. van der

    1965-01-01

    The reaction of ketene with triphenyllead hydroxide in diethyl ether gave (triphenylplumbyl)acetic anhydride, (Ph3PbCH2CO)2O, the first anhydride-substituted organolead compound known. The reaction of ketene with triphenyllead acetate in absolute ethanol gave ethyl (triphenylplumbyl)acetate, Ph3PbCH

  9. Preparation of epoxy/zirconia hybrid materials via in situ polymerization using zirconium alkoxide coordinated with acid anhydride

    Energy Technology Data Exchange (ETDEWEB)

    Ochi, Mitsukazu, E-mail: mochi@ipcku.kansai-u.ac.jp [Faculty of Chemistry, Materials and Bioengineering, Kansai University, 3-3-35 Suita-shi, Osaka 564-8680 (Japan); Nii, Daisuke; Harada, Miyuki [Faculty of Chemistry, Materials and Bioengineering, Kansai University, 3-3-35 Suita-shi, Osaka 564-8680 (Japan)

    2011-09-15

    Highlights: {yields} Novel epoxy/zirconia hybrid materials were synthesized via in situ polymerization using zirconium alkoxide coordinated with acid anhydride. {yields} The half-ester compound of acid anhydride desorbed from zirconium played as curing agent of epoxy resin. {yields} The zirconia was uniformly dispersed in the epoxy matrix on the nanometer or sub-nanometer scale by synchronizing the epoxy curing and sol-gel reactions. {yields} The refractive indices of the hybrid materials significantly improved with an increase in the zirconia content. - Abstract: Novel epoxy/zirconia hybrid materials were synthesized using a bisphenol A epoxy resin (diglycidyl ether of bisphenol A; DGEBA), zirconium(IV)-n-propoxide (ZTNP), and hexahydrophthalic anhydride (HHPA) via in situ polymerization. HHPA played two roles in this system: it acted as a modifier to control the hydrolysis and condensation reactions of zirconium alkoxide and also as a curing agent - the half-ester compound of HHPA desorbed from zirconium reacted with the epoxy resin to form the epoxy network. As a result, both the sol-gel reaction and epoxy curing occurred simultaneously in a homogeneous solution, and organic-inorganic hybrid materials were readily obtained. Further, the zirconia produced by the in situ polymerization was uniformly dispersed in the epoxy matrix on the nanometer or sub-nanometer scale; thus, hybrid materials that exhibited excellent optical transparency were obtained. Furthermore, the heat resistance of the hybrid materials could be improved by hybridization with zirconia. And, the refractive indices of the hybrid materials significantly improved with an increase in the zirconia content.

  10. Imide modified epoxy matrix resins

    Science.gov (United States)

    Scola, D. A.

    1984-01-01

    The results of a program designed to develop tough imide modified epoxy resins cured by bisimide amine (BIA) hardeners are described. State-of-the-art epoxides MY720 and DER383 were used, and four bismide amines were evaluated. These were the BIA's derived from the 6F anhydride (4,4'-(hexafluoroisopropylidene) bis(phthalic anhydride) and the diamines 3,3'-diaminodiphynyl sulfone, 4,4'-oxygianiline, 4,4'-methylene dianiline, and 1,12-dodecane diamine. A key intermediate, designated 6F anhydride, is required for the synthesis of the bisimide amines. Reaction parameters to synthesize a precursor to the 6F anhydride (6FHC) in high yields were investigated. The catalyst trifluoromethane sulfonic acid was studied. Although small scale runs yielded the 6FHC in 50 percent yield, efforts to ranslate these results to a larger scale synthesis gave the 6FHC in only 9 percent yield. Results show that the concept of using bisimide amine as curing agents to improve the toughness properties of epoxies is valid.

  11. Chemical modification with phthalic anhydride and chitosan: Viable options for the stabilization of raw starch digesting amylase from Aspergillus carbonarius.

    Science.gov (United States)

    Nwagu, Tochukwu Nwamaka; Okolo, Bartholomew; Aoyagi, Hideki; Yoshida, Shigeki

    2017-06-01

    The raw starch digesting type of amylase (RSDA) presents greater opportunities for process efficiency at cheaper cost and shorter time compared to regular amylases. Chemical modification is a simple and rapid method toward their stabilization for a wider application. RSDA from Aspergillus carbonarius was modified with either phthalic anhydride (PA) or chitosan. Activity retention was 87.3% for PA-modified and 80.9% for chitosan-modified RSDA. Optimum pH shifted from 5 to 7 after PA-modification. Optimum temperature changed from 30°C (native) to 30-40°C and 60°C for PA-modified and chitosan-modified, respectively. Activation energy (kJmol(-1)) for hydrolysis was 13.5, 12.7, and 10.2 while the activation energy for thermal denaturation was 32.8, 80.3, 81.9 for free, PA-modified and chitosan-modified, respectively. The specificity constants (Vmax/Km) were 73.2 for PA-modified, 63.1 for chitosan-modified and 77.1 for native RSDA. The half-life (h) of the RSDA at 80°C was increased from 6.1 to 25.7 for the PA-modified and 138.6 for the chitosan derivative. Modification also led to increase in D value, activation enthalpy and Gibbs free energy of enzyme deactivation. Fluorescence spectra showed that center of spectral mass decreased for the PA-modified RSDA but increased for chitosan modified RSDA. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Anhydride functionalised calcium ferrite nanoparticles: a new selective magnetic material for enrichment of lead ions from water and food samples.

    Science.gov (United States)

    Pirouz, Mojgan Jafari; Beyki, Mostafa Hossein; Shemirani, Farzaneh

    2015-03-01

    In this research a sonochemistry route for manufacture of uniform nanocrystalline CaFe2O4 and its anhydride functionalisation were reported. The potential of raw and modified material as a magnetically separable sorbent in selective enrichment of lead ions from water and food samples is outlined. This material was characterised using FT-IR, XRD, SEM and VSM techniques. The SEM and VSM results indicated that the calcium ferrite nanoparticles are sphere-like particles possessing superparamagnetic properties with an average diameter of 40 nm. Various analytical parameters, including pH, contact time, type and concentration of eluent, adsorption capacity, sample volume and interference of ions, were optimised. Following a modification by anhydride, calcium ferrite selectivity toward lead ions was raised more than twofold compared to the unmodified nanoparticles. Finally a pre-concentration procedure was applied for determination of trace Pb(II) in canned tuna fish, canned tomato paste, parsley, milk and well-water samples with satisfactory results.

  13. Aluminum pigment encapsulated by in situ copolymerization of styrene and maleic acid

    Science.gov (United States)

    Liu, Hui; Ye, Hongqi; Tang, Xinde

    2007-11-01

    To improve its anticorrosion property, aluminum pigment was encapsulated by in situ copolymerization of styrene (St) and maleic acid (MA). It was found that the conversion of monomers (C), the percentage of grafting (PG) and the grafting efficiency (GE) could attain 92%, 12%, 25%, respectively, when m(BPO)/ m(St + MA) = 10% and m(St + MA)/ m(Al) = 10%. The optimum condition for protection factor was studied according to an orthogonal testing. When m(St + MA)/ m(Al) was 20%, the encapsulated aluminum pigment simultaneously showed good anticorrosion property and luster. FTIR, SEM and particle size analysis indicated that aluminum pigment had been successfully encapsulated with styrene-maleic acid copolymer by in situ copolymerization, which remarkably improved its anticorrosion property and the chelate complex formed between SMA and Al(III) was possibly the actual corrosion inhibitor.

  14. Swelling characterization of gamma-radiation induced crosslinked acrylamide/maleic acid hydrogels in urea solutions

    Energy Technology Data Exchange (ETDEWEB)

    Karadag, Erdener [Department of Chemistry, Fen-Edebiyat Faculty, Adnan Menderes University, TR09010 Aydin (Turkey)]. E-mail: ekaradag@adu.edu.tr; Uzuem, Omer Baris [Department of Chemistry, Fen-Edebiyat Faculty, Adnan Menderes University, TR09010 Aydin (Turkey); Saraydin, Dursun [Department of Chemistry, Cumhuriyet University, 58140 Sivas (Turkey); Gueven, Olgun [Department of Chemistry, Hacettepe University, 06532 Beytepe, Ankara (Turkey)

    2006-07-01

    Swelling behaviors of crosslinked acrylamide/maleic acid (CAMA) hydrogels synthesized by gamma-radiation crosslinking of acrylamide and maleic acid in aqueous urea solutions were investigated. CAMA hydrogels containing different amounts of maleic acid were obtained in the form of rods via a radiation technique. Swelling experiments were performed in two different urea concentrations at 25 {sup o}C, gravimetrically. The hydrogels showed enormous swelling in aqueous medium and displayed swelling characteristics that were highly dependent on the chemical composition of the hydrogels and irradiation dose. Diffusion behavior and some swelling kinetics parameters were investigated. The values of the swelling percent of CAMA hydrogels were between 935% and 5212%, while the values of the swelling percent of acrylamide hydrogels were between 669% and 923%. The difference of the concentrations of urea solutions was not affected by the swelling properties of the hydrogel systems. Urea/water diffusion into hydrogels was found to be non-Fickian in character. Equilibrium urea/water contents of the hydrogel systems were changed between 0.8699 and 0.9812.

  15. Whole slurry saccharification and fermentation of maleic acid-pretreated rice straw for ethanol production.

    Science.gov (United States)

    Jung, Young Hoon; Park, Hyun Min; Kim, Kyoung Heon

    2015-09-01

    We evaluated the feasibility of whole slurry (pretreated lignocellulose) saccharification and fermentation for producing ethanol from maleic acid-pretreated rice straw. The optimized conditions for pretreatment were to treat rice straw at a high temperature (190 °C) with 1 % (w/v) maleic acid for a short duration (3 min ramping to 190 °C and 3 min holding at 190 °C). Enzymatic digestibility (based on theoretical glucose yield) of cellulose in the pretreated rice straw was 91.5 %. Whole slurry saccharification and fermentation of pretreated rice straw resulted in 83.2 % final yield of ethanol based on the initial quantity of glucan in untreated rice straw. These findings indicate that maleic acid pretreatment results in a high yield of ethanol from fermentation of whole slurry even without conditioning or detoxification of the slurry. Additionally, the separation of solids and liquid is not required; therefore, the economics of cellulosic ethanol fuel production are significantly improved. We also demonstrated whole slurry saccharification and fermentation of pretreated lignocellulose, which has rarely been reported.

  16. Multifunctional electroactive electrospun nanofiber structures from water solution blends of PVA/ODA-MMT and poly(maleic acid-alt-acrylic acid): effects of Ag, organoclay, structural rearrangement and NaOH doping factors

    Science.gov (United States)

    Şimşek, Murat; Rzayev, Zakir M. O.; Bunyatova, Ulviya

    2016-06-01

    Novel multifunctional colloidal polymer nanofiber electrolytes were fabricated by green reactive electrospinning nanotechnology from various water solution/dispersed blends of poly (vinyl alcohol-co-vinyl acetate) (PVA)/octadecyl amine-montmorillonite (ODA-MMT) as matrix polymer nanocomposite and poly(maleic acid-alt-acrylic acid) (poly(MAc-alt-AA) and/or its Ag-carrying complex as partner copolymers. Polymer nanofiber electrolytes were characterized using FTIR, XRD, thermal (DSC, TGA-DTG), SEM, and electrical analysis methods. Effects of partner copolymers, organoclay, in situ generated silver nanoparticles (AgNPs), and annealing procedure on physical and chemical properties of polymer composite nanofibers were investigated. The electrical properties (resistance, conductivity, activation energy) of nanofibers with/without NaOH doping agent were also evaluated. This work presented a structural rearrangement of nanofiber mats by annealing via decarboxylation of anhydride units with the formation of new conjugated double bond sites onto partner copolymer main chains. It was also found that the semiconductor behaviors of nanofiber structures were essentially improved with increasing temperature and fraction of partner copolymers as well as presence of organoclay and AgNPs in nanofiber composite.

  17. Granular size of potato starch affects structural properties, octenylsuccinic anhydride modification and flowability.

    Science.gov (United States)

    Wang, Chan; Tang, Chuan-He; Fu, Xiong; Huang, Qiang; Zhang, Bin

    2016-12-01

    Native potato starch (PS) granules were separated into three size fractions: larger than 30μm (P-L), 15-30μm (P-M), and smaller than 15μm (P-S). The morphological and crystalline structure of fractionated potato starches were investigated by light and scanning electron microscopy (SEM), X-ray diffraction (XRD) and differential scanning calorimetry (DSC). The P-L fraction showed ellipsoidal shape and B-type X-ray pattern, whereas the P-S fraction had spherical shape and A-type pattern. The fluorophore-assisted capillary electrophoresis data showed that the P-L fraction had more B2 chains and less short A and B1 chains than the P-S counterparts. Smaller granules with larger specific surface area had higher degree of substitution when reacted with octenylsuccinic anhydride (OSA), and showed more uniform distribution of octenylsuccinate substituents. Both OSA modified and unmodified P-S samples showed higher flowability compared with the P-L counterparts.

  18. 红外光谱法测定顺丁烯二酸硬脂酸聚氧乙烯酯单酯二乙醇酰胺含量%The maleic acid poloyxyethylene fatty acide ester monoester diethanolamine assay in infrared spectroscopy

    Institute of Scientific and Technical Information of China (English)

    沈芳; 赵志明

    2013-01-01

      以顺丁烯二酸酐,硬脂酸聚氧乙烯酯为原料制备顺丁烯二酸硬脂酸聚氧乙烯酯单酯,提纯后再与二乙醇胺反应,制备顺丁烯二酸硬脂酸聚氧乙烯酯单酯二乙醇酰胺,提纯后制备酰胺标准物.选择硫氰酸钾为内标物,采用红外光谱法对顺丁烯二酸硬脂酸聚氧乙烯酯单酯二乙醇酰胺与内标物的混合样品进行测试.以酰胺与硫氰酸钾的质量比为横坐标,所对应的峰高比为纵坐标绘制标准曲线.得到的线性回归方程为y=0.3203x-0.0034,相关系数为R2=0.9991,方法的相对标准偏差为0.48%,回收率为91.67%~103.85%.%On this paper the maleic acid polyoxyethylene fatty acid ester monoester diethanolamide was quantitative analysisd by Infrared spectra. First, prepare maleic aicd poloyxyethylene fatty c monoester with maleic anhydride and stearic ester polyoxye , purification and reactact with diethanolamine, than prepare maleic aicd poloyxyethylene fatty ester monoester diethanolamine amide purified preparation of standard. Choose potassium thiocyanate as internal stangard, grinding with amide simples together ,and test with infrared compression method. Make the mass ration amide and potassium thiocyanate of x-coodinate, conresponding to the peak hight ration of the vertical coodinate to map stsndard curve. Linear ression equation is y=0.3203x-0.0034, the correlation cofficient R2=0.9991, and determinade the precision and recovery of the infrared spectroscopy,is to say,the relative standard deviation equal 0.48%, recovery equal 91.67%~101.0%.

  19. Highly efficient peptide formation from N-acetylaminoacyl-AMP anhydride and free amino acid

    Science.gov (United States)

    Mullins, D. W., Jr.; Lacey, J. C., Jr.

    1983-01-01

    The kinetics of formation of the N-blocked dipeptide, N-acetylglycylglycine, from N-acetylglycyl adenylate anhydride and glycine in aqueous solution at 25 C, and at various PH's are reported. The reaction is of interest in that over a physiologically relevant pH range (6-8), peptide synthesis proceeds more rapidly than hydrolysis, even at those pH's at which this compound becomes increasingly susceptible to base-catalyzed hydrolysis. Under similar conditions, the corresponding unblocked aminoacyl adenylate anhydrides are considerably more unstable, and undergo appreciable hydrlysis in the presence of free amino acid. Because N-blocked aminoacyl adenylate anhydrides serve as model compounds of peptidyl adenylate anhydrides, these results suggest that primitive amino acid polymerization systems may have operated by cyclic reactivation of the peptidyl carboxyl group, rather than that of the incoming amino acid.

  20. TRIMELLITIC ANHYDRIDE (TMA) HYPERSENSITIVITY IN MICE AFTER DERMAL AND INTRATRACHAEL (IT) EXPOSURES

    Science.gov (United States)

    ABSTRACT for 2001 DMS213TRIMELLITIC ANHYDRIDE (TMA) HYPERSENSITIVITY INMICE AFTER DERMAL AND INTRATRACHEAL (IT) EXPOSURES. E Boykin, M Ward, MJ Selgrade, and D Sailstad. NHEERL, ORD, US EPA, RTP, NC, USA.TMA causes respiratory hypersensitivity (RH) responses. W...

  1. Determination of the Preferred Structure, Dynamics, and Planarity of Substituted Anhydrides by Cp-Ftmw

    Science.gov (United States)

    McMahon, Timothy J.; Bailey, Josiah R.; Bird, Ryan G.; Pratt, David

    2016-06-01

    The planarity of five-membered rings is derived from a competition between ring-angle strain and stability of the torsional angles. The planar form maximizes the already stressed, smaller-than-normal, C-C bond angles, while puckering reduces the unfavorable eclipsed interactions. The structure, dynamics, and planarity of three anhydrides, succinic, methylsuccinic, and methylene (itaconic) anhydride, were studied and compared using chirped-pulse Fourier transform microwave spectroscopy.

  2. Evaluation of Surface Free Energy of Maleopimaric Anhydride Modified 2 K-WPU by Contact Angle Goniometry%接触角法测量马来海松酸改性双组分水性聚氨酯的表面能

    Institute of Scientific and Technical Information of China (English)

    司红燕; 商士斌; 刘鹤; 王丹; 廖圣良; 宋湛谦

    2016-01-01

    将亲水改性的多异氰酸酯分别与马来海松酸改性聚酯多元醇( MPP)、聚酯多元醇( PP)和Bayhydrol D270聚酯多元醇水分散体进行复合交联制得MPP-2K-WPU、PP-2K-WPU和D270-2K-WPU,并采用FT-IR和DSC对产物进行表征。利用接触角法研究了n(—NCO)∶n(—OH)及多元醇组分种类对2K-WPU涂膜接触角、表面能和耐水性的影响,并采用Equation of State法和Owens-Wendt-Rabel-Kaelble法对试验数据进行分析。结果表明,与甲酰胺系列(甲酰胺、甲酰胺-二碘甲烷)检测液体相比,水系列(水、水-二碘甲烷)检测液体能更好地对2K-WPU涂膜表面性能进行描述;随着n(—NCO)∶n(—OH)的增加,MPP-2K-WPU的表面能先减小后增大,耐水性呈现先增强后减弱的趋势,当n(—NCO)∶n(—OH)为1.5∶1时其表面能最小、耐水性最强;与2种对照样( PP-2K-WPU和D270-2K-WPU)相比,MPP-2K-WPU的表面能最小且耐水性最强。%MPP-2K-WPU, PP-2K-WPU and D270-2K-WPU were prepared by crosslinking of hydrophilic-modified polyisocyanate with maleopimaric acid modified polyester polyol ( MPP) , polyester polyol ( PP) and Bayhydrol D270 polyester polyol dispersion, respectively. The products were characterized by FT-IR and DSC. The influences of n(—NCO)∶n(—OH) and type of polyol component on contact angle, surface free energy and water resistance of 2K-WPU films were investigated. The experimental data were analyzed using Equation of State method and Owens-Wendt-Rabel-Kaelble method. The results showed that water series test liquid (water, water-diiodomethane) was better to describe the surface properties of 2K-WPU, if it was compared with formamide series test liquid ( formamide, formamide-diiodomethane) . With increasing of n(—NCO)∶n(—OH) , the surface free energy of MPP-2K-WPU decreased firstly and then increased, and the water resistance increased firstly and then decreased. MPP-2K-WPU exhibited the minimum surface free energy and the

  3. Design of a multi-dopamine-modified polymer ligand optimally suited for interfacing magnetic nanoparticles with biological systems.

    Science.gov (United States)

    Wang, Wentao; Ji, Xin; Na, Hyon Bin; Safi, Malak; Smith, Alexandra; Palui, Goutam; Perez, J Manuel; Mattoussi, Hedi

    2014-06-03

    We have designed a set of multifunctional and multicoordinating polymer ligands that are optimally suited for surface functionalizing iron oxide and potentially other magnetic nanoparticles (NPs) and promoting their integration into biological systems. The amphiphilic polymers are prepared by coupling (via nucleophilic addition) several amine-terminated dopamine anchoring groups, poly(ethylene glycol) moieties, and reactive groups onto a poly(isobutylene-alt-maleic anhydride) (PIMA) chain. This design greatly benefits from the highly efficient and reagent-free one-step reaction of maleic anhydride groups with amine-containing molecules. The availability of several dopamine groups in the same ligand greatly enhances the ligand affinity, via multiple coordination, to the magnetic NPs, while the hydrophilic and reactive groups promote colloidal stability in buffer media and allow subsequent conjugation with target biomolecules. Iron oxide nanoparticles ligand exchanged with these polymer ligands have a compact hydrodynamic size and exhibit enhanced long-term colloidal stability over the pH range of 4-12 and in the presence of excess electrolytes. Nanoparticles ligated with terminally reactive polymers have been easily coupled to target dyes and tested in live cell imaging with no measurable cytotoxicity. Finally, the resulting hydrophilic nanoparticles exhibit large and size-dependent r2 relaxivity values.

  4. Grafting of chitosan as a biopolymer onto wool fabric using anhydride bridge and its antibacterial property.

    Science.gov (United States)

    Ranjbar-Mohammadi, Marziyeh; Arami, Mokhtar; Bahrami, Hajir; Mazaheri, Firoozmehr; Mahmoodi, Niyaz Mohammad

    2010-04-01

    Weak binding of chitosan on the wool constitutes the main problem in its application. In this paper, the surface modification of wool fabric using anhydrides to graft the chitosan was studied. Weight gain, antibacterial and antifelting properties of the chitosan grafted-acylated wool fabric were investigated. Wool fabrics were acylated with two anhydrides, succinic anhydride (SA) and phthalic anhydride (PA), using different solvents (dimethylsulfoxide (DMSO) and N,N-dimethyl formamide (DMF)). The effects of anhydrides, solvents, anhydride concentration, liquor ratio (L:R) and reaction time on acylation of wool were investigated. Chitosan was grafted to the acylated wool and the effects of pH, chitosan concentration, and reaction time on chitosan grafting of acylated wool were evaluated. Fourier transform infra-red (FTIR), scanning electron microscope (SEM), differential scanning colorimetry (DSC) and weight gain analyses provided evidence that chitosan was grafted on to the acylated wool through the formation of new covalent bonds. The grafted samples have antibacterial potential due to existence of the antibacterial property of chitosan. In addition, the chitosan grafted-acylated wool samples have antifelting property. The findings of this research support the potential production of new environmentally friendly textile fabrics. Copyright (c) 2009 Elsevier B.V. All rights reserved.

  5. Convergence of Biological Nitration and Nitrosation via Symmetrical Nitrous Anhydride

    Science.gov (United States)

    Vitturi, Dario A.; Minarrieta, Lucia; Salvatore, Sonia R.; Postlethwait, Edward M.; Fazzari, Marco; Ferrer-Sueta, Gerardo; Lancaster, Jack R.; Freeman, Bruce A.; Schopfer, Francisco J.

    2015-01-01

    Current perspective holds that the generation of secondary signaling mediators from nitrite (NO2−) requires acidification to nitrous acid (HNO2) or metal catalysis. Herein, the use of stable isotope-labeled NO2− and LC-MS/MS analysis of products revealed that NO2− also participates in fatty acid nitration and thiol S-nitrosation at neutral pH. These reactions occur in the absence of metal centers and are stimulated by nitric oxide (•NO) autoxidation via symmetrical dinitrogen trioxide (nitrous anhydride, symN2O3) formation. While theoretical models have predicted physiological symN2O3 formation, its generation is now demonstrated in aqueous reaction systems, cell models and in viv, with the concerted reactions of •NO and NO2− shown to be critical for symN2O3 formation. These results reveal new mechanisms underlying the NO2− propagation of •NO signaling and the regulation of both biomolecule function and signaling network activity via NO2−-dependent nitrosation and nitration reactions. PMID:26006011

  6. Modification of pineapple peel fiber as metal ion adsorbent through reaction with succinic anhydride in pyridine and dimethyl sulfoxide solvents.

    Science.gov (United States)

    Hu, Xiuyi; Zhao, Mouming; Huang, Huihua

    2010-08-01

    Reactions between saponified pineapple peel fiber (SPPF) and succinic anhydride were performed in refluxed pyridine and dimethyl sulfoxide to obtain modified pineapple peel fiber in pyridine (MPPF-PY) and modified pineapple peel fiber in dimethyl sulfoxide at room temperature (MPPF-DMRT) and at 70 degrees C (MPPF-DM70) as novel metal ionic adsorbents. The modified pineapple peel fibers were characterized by Fourier transform infrared (FTIR) and X-ray diffraction (XRD). The MPPF-PY, MPPF-DMRT, and MPPF-DM70 showed higher Cu2+, Cd2+, and Pb2+ adsorption capacity than raw pineapple peel fiber (RPPF) and SPPF. Dimethyl sulfoxide favored introduction of a carboxylic function group into pineapple peel fiber compared with pyridine. The elevated reaction temperature of dimethyl sulfoxide could increase the adsorption capacity of the modified pineapple fiber. Optimum pH values for Cu2+, Cd2+, and Pb2+ removal by MPPF-DM70 were pH 5.5, 7.5, and 5.5, respectively. The Cu2+, Cd2+, and Pb2+ adsorptions by MPPF-DM70 followed the pseudo second-order kinetics model and Langmuir model.

  7. Equilibrium of Extraction of Succinic,Malic,Maleic and Fumaric Acids with Trioctylamine

    Institute of Scientific and Technical Information of China (English)

    LIZhenyu; QINWei; 等

    2002-01-01

    Extraction equilibrium features of succinic acid,malic acid,maleic acid and fumaric acid were investigated systematically with trioctylamine (TOA) in chloroform,4-methyl-2-pentanone (MIBK) and 1-octanol.Fourier transform-infrared(FTIR) spectroscopic analysis of organic samples loaded with the acid show that amine forms 1:1 complex of ion-pair association with succinic acid,malic acid and maleic acid,and 1:1,2:1 complex of ion-pair association with fumaric acid.It is proposed that the complex forms depend on the second dissociation constant of the dibasic acid,pKa2.Results of equilibrium experiments show that diluents affects extraction behavior,and depend on the solute concentration.Protic diluents,chloroform and 1-octanol,are more effective than the others when the equilibrium solute concentration.Protic diluents,chloroform and 1-octanol,are more effective tthan the others when the equilibrium solute concentration is lower than 1:1 stoichiometry of TOA to acid,otherwise the extraction ability shows that MIBK>1-octanol>chloroform for malic and maleic acids,and 1-octanol>MIBK>chloroform for succinic acid.Overloading(Solute concentration in organic phase is lager than TOA concentration) appears for all of the studied acids, and the sequence of overloading amount is the same as that of distribution constant of diluent.The results show that the sequence of extraction ability of different acid is the same as that of acidity at low equilibrium solute concentrations,while it is the same as the sequence of hydrophobicity at high equilibrium concentrations.

  8. Factors influencing catalytic wet peroxide oxidation of maleic acid in aqueous phase over copper/micelle templated silica-3-aminopropyltrimethoxysilane catalyst.

    Science.gov (United States)

    Daniel, Lilian; Katima, Jamidu H Y

    2009-01-01

    Catalytic wet peroxide oxidation (CWPO) of initial maleic acid feed concentration (0.005 to 0.03 M) was carried out in a temperature range of 20-50 degrees Celsius, on micelle templated silica-3-aminopropyltrimethoxysilane (MTS-AMP) supported copper catalyst. The influence of various operating parameters such as initial feed concentration of maleic acid, temperature, catalyst loading and the stability of the catalyst were investigated. CWPO reactions were performed in a stirred batch reactor at an atmospheric pressure in the presence of H(2)O(2) as an oxidant. Total conversion of maleic acid into acetic acid was obtained under mild conditions (i.e. atmospheric pressure and 40 degrees Celsius). Blank experiments showed no measurable maleic acid conversion (i.e. only approximately 0.5% conversion of initial maleic acid), indicating that a significant oxidation reaction of maleic acid is enhanced by the presence of a catalyst. Copper on micelle templated silica-3-aminopropyltrimethoxysilane catalyst therefore was found to be suitable for aqueous phase oxidation of maleic acid with 100% of maleic acid conversion.

  9. Teratologic assessment of maleic hydrazide and daminozide, and formulations of ethoxyquin, thiabendazole and naled in rats.

    Science.gov (United States)

    Khera, K S; Whalen, C; Trivett, G; Angers, G

    1979-01-01

    Teratogenicity studies were conducted in rats treated orally from days 6-15 of gestation with single daily doses of 400-1600 mg/kg of maleic hydrazide, 300-1000 mg/kg daminozide, 125-500 mg/kg ethoxyquin or thiabendazole, or 25-100 mg/kg naled. Dams were killed on the 22nd day of gestation, and fetuses were evaluated by routine teratologic methods. No adverse effect was related to any treatment other than an increased incidence of anomalous fetuses at the highest dose (500 mg/kg) of thiabendazole.

  10. Synthesis and Characteristic Study on Complexes of Europium(Ⅲ) and Maleic Acid Doped with Non-Fluorescent Ions

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Complex of europium (Ⅲ) with maleic acid, and binuclear complexes of europium(Ⅲ)with maleic acid doped with non-fluorescent ions gadolinium, lanthanum and yttrium, were synthesized. The compositions and structures of complexes were characterized with elemental analysis, single crystal X-ray diffraction, IR and DSC-TG. Fluorescent properties were studied with fluorescence spectrum. The results indicated that the strongest fluorescent complexes were obtained when the ratio of europium and non-fluorescent ion was 8: 2. The order of Eu3+ fluorescence strengthened by three doped rare earths was Gd3+>La3+>Y3+.

  11. Modified and Unmodified Zinc Oxide as Coagent in Elastomer Compounds

    Directory of Open Access Journals (Sweden)

    Kołodziejczak-Radzimska Agnieszka

    2014-09-01

    Full Text Available The aim of this work was to study the activity of unmodified and modified ZnO in the peroxide crosslinking of hydrogenated acrylonitrile-butadiene elastomer (HNBR and ethylene-propylene copolymer (EPM. In the first step, zinc oxide was obtained by emulsion precipitation. Maleic acid was introduced onto the surface of ZnO using an in situ method. The unmodified and modified zinc oxide was characterized using dispersive and morphological analysis, BET surface area analysis, and elemental, spectroscopic and thermal analysis. In the second stage of the research, the ZnO/MA systems were incorporated into the structure of elastomer compounds improving the kinetic and mechanical properties of vulcanizates. The proposed modification method had a favorable effect on the physicochemical properties of the zinc oxide and on the kinetic and mechanical properties of the vulcanizates. This study demonstrated that modification of zinc oxide by maleic acid is a promising technique.

  12. Biological effect of maleic acid hydrazide on Yellow Nutsedge (Cyperus esculentus L.

    Directory of Open Access Journals (Sweden)

    Bohren, Christian

    2014-02-01

    Full Text Available Yellow Nutsedge (Cyperus esculentus L. belongs to the family of Cyperaceae. It propagates exclusively with tubers in the ground. Its abundance has strongly increased in Switzerland in the last two decades. Main reasons for this increase are changing land use and production systems, a difficult herbicide control and a low awareness level among the farmers. The actual invasion is enhanced by unintended dislocation of tubers by machines or crops/crop waste, lack of knowledge of infested fields and missing supporting measures. An obligation to announce infested fields and to control Yellow Nutsedge is currently discussed in Switzerland. Such an obligation would help contractors and buyers of crops to reduce unintended dislocation of tubers. Cleaning up infested plots is quickly expensive and complex. Maleic acid hydrazide is actually used for preventing potato tubers to germinate in stock. We tested Fazor (maleic acid hydrazide and Asulox (asulam for its efficacy on preventing germination of Yellow Nutsedge tubers. The results of our pot trial in the greenhouse are clear. The expected efficiency was not observed. Furthermore the complexity of problems with this species in agriculture is discussed and some ideas for a control strategy are given in this paper.

  13. Meiotic changes in Vicia faba L. subsequent to treatments of hydrazine hydrate and maleic hydrazide

    Directory of Open Access Journals (Sweden)

    Shaheen Husain

    2013-01-01

    Full Text Available Assessing the impact of mutagens for creating variations in crops like faba bean (Vicia faba L. is an important criterion in the contemporary world where food insecurity and malnutrition is alarming at the doors of various nations. Impact of two chemical mutagens viz. hydrazine hydrate (HZ and maleic hydrazide (MH on the two varieties (NDF-1 and HB-405 of Vicia faba were analysed in terms of meiotic behavior and pollen sterility. Since there are not enough data about the effect of these mutagens on the chromosomal behaviors of Vicia faba, this study presents the role of hydrazine hydrate and maleic hydrazide as well as various types of chromosomal aberrations in crop improvement. The lower concentration of mutagens showed less pollen sterility compared to the higher concentrations. Manipulation of plant structural component to induce desirable alternations provides valuable material for the breeders and could be used favorably for increasing mutation rate and obtaining a desirable spectrum of mutation in faba beans based on preliminary studies of cell division.

  14. Influence of maleic acid copolymers on calcium orthophosphates crystallization at low temperature

    Science.gov (United States)

    Pelin, Irina M.; Popescu, Irina; Suflet, Dana M.; Aflori, Magdalena; Bulacovschi, Victor

    2013-08-01

    The goal of this study was to investigate the maleic acid copolymers role on calcium orthophosphates crystallization at low temperature. In this respect, two maleic acid copolymers with different structures [poly(sodium maleate-co-vinyl acetate) and poly(sodium maleate-co-methyl methacrylate)] were used. The syntheses of the calcium orthophosphates in the absence and in the presence of the copolymers were performed through the wet chemical method using calcium nitrate, ammonium dihydrogen phosphate and ammonium hydroxide as reactants. The syntheses were monitored in situ by potentiometric and conductometric measurements. To ensure the transformation of less thermodynamically stable calcium orthophosphates into more stable forms, the samples were aged 30 days in mother solutions, at room temperature. The presence of the copolymers in the final products was evidenced by FTIR spectroscopy and thermogravimetric analysis. Scanning and transmission electron microscopy and laser light scattering measurements gave information about the composites morphology and the size of the formed structures. X-ray diffraction evidenced that, as a function of comonomer structure and of copolymer concentration, the products could contain hydroxyapatite with low crystallinity, calcium-deficient or carbonated hydroxyapatite. At high concentration of poly(sodium maleate-co-methyl methacrylate) the transformation of brushite into apatitic structures was inhibited.

  15. 顺酐加氢产物精制丁二酸的工艺研究%Purifying Technology of Succinic Acid from Product of M aleic Anhydride Hydrogenation

    Institute of Scientific and Technical Information of China (English)

    田丹; 霍稳周; 吕清林; 乔凯; 孟宪革; 李守田

    2013-01-01

    The process of succinic acid purifying from product of maleic anhydride hydrogenation was studied .The effects of distillation pressure ,temperature and reflux ratio on the process of vacuum distillation were investigated ;it also discussed the effects of reaction time and molar ratio of water to succinic anhydride on hydrolysis ;meanwhile ,the effect of temperature on the crystallization was concerned . The pure succinic acid was acquired through vacuum distillation , hydrolyzation and crystallization .The process conditions of purifying technology of succinic acid were detemined .The results show that the yield of succinic acid is more than 70% and purity of the product can reach 99 .5% even more under the conditions of vaccum distillation temperature 75~85 ℃ ,distillation pressure 200~300 Pa ,hydrolysis temperature 100 ℃ ,molar ratio of water to succinic anhydride 4~5 ,reaction time 2 h .%对顺酐加氢产物精制丁二酸的工艺进行了研究。考察了蒸馏压力、蒸馏温度及回流比对减压蒸馏过程的影响;考察了水解时间、水与酸酐物质的量比对水解过程的影响;考察了结晶温度对结晶过程的影响。确定了顺酐加氢产物减压蒸馏后水解结晶精制丁二酸的方法及工艺条件。结果表明,在减压蒸馏温度为75~85℃,蒸馏压力为200~300 Pa ,水解温度为100℃,水与丁二酸酐物质的量比为4~5,水解时间为2 h的条件下,得到的丁二酸产品收率≥70%,纯度≥99.5%。

  16. Study on Curing Reaction of Epoxidized Linseed Oil with Anhydrides%环氧亚麻油与酸酐固化反应研究

    Institute of Scientific and Technical Information of China (English)

    董宇; 裴帆; 石春韬; 王雪; 许艳玲; 李萍

    2015-01-01

    Epoxidized linseed oil is a type of epoxy resin synthesized by the epoxidation reaction of linsee d oil. Thermosetting epoxy resin-based polymer composites with a variety of properties can be prepared after the reaction of epoxy resin and curing agents, which can be used in many fields. In this work, the curing reaction of epoxidized linseed oil was studied and the optimized reaction conditions were also obtained by the application of orthogonal experimental method based on the best selection of curing agent and accelerator. Fourier transform infrared spectroscopy(FT-IR)and differential scanning calorimetry (DSC)techniques were applied to investigate the curing reaction process and characterization. The results show that a mixture of maleic anhydride and phthalic anhydride (molar ratio 0.83﹕0.17) was the best curing agent while N, N-dimethylbenzylamine was the best accelerator. The factors impacting curing reaction were in the order of mixed anhydride/epoxy ratio > temperature >amount of accelerator > time. Curing degree of the final product could reach 97.13% under the following optimized conditions:mixed anhydride / epoxy ratio was 1.2﹕1.0 (molar ratio), the amount of accelerator was 2.5%, the temperature and time were 120 ℃ and 4 h,respectively. IR characteristic absorption of epoxy and anhydride gradually disappeared as the proceeding of the reaction and the curing reaction tended to be complete. Curing reaction of epoxidized linseed oil with mixed anhydride is an exothermic one with peak temperature at 182.6 ℃ and reaction enthalpy is -130.2 J/g.%环氧亚麻油是亚麻油通过环氧化反应合成的环氧树脂,其可进一步与固化剂反应,制备具有多种性能的热固性环氧树脂基复合材料,在多种领域具有广泛应用。文中研究了环氧亚麻油的固化反应,在选择最佳固化剂和促进剂的基础上,用正交试验优化反应条件,红外光谱表征固化反应过程,差示扫描量热法(DSC

  17. Curing behaviors and properties of an extrinsic toughened epoxy/anhydride system and an intrinsic toughened epoxy/anhydride system

    Energy Technology Data Exchange (ETDEWEB)

    Fan, Mengjin; Liu, Jialin; Li, Xiangyuan [Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing University of Chemical Technology, Beijing 100029 (China); Cheng, Jue, E-mail: chengjue@mail.buct.edu.cn [Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing University of Chemical Technology, Beijing 100029 (China); Zhang, Junying, E-mail: zjybuct@gmail.com [Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing University of Chemical Technology, Beijing 100029 (China)

    2013-02-20

    Highlights: ► Two curing systems (ETRS and ITRS) with similar chemical composite were prepared. ► The curing kinetics of the ETRS and the novel ITRS were comparatively studied. ► Crosslinking density can affect the kinetic schemes of the two curing systems. ► Their mechanical properties and thermal stabilities were also comparatively studied. ► Crosslinking density may play an influential role in mechanical properties. - Abstract: The curing kinetics of an extrinsic toughened epoxy (mixture of diglycidyl ether of bisphenol-A and 1,4-butanediol epoxy resin, DGEBA/DGEBD) and an intrinsic toughened epoxy (ethoxylated bisphenol-A epoxy resin with two oxyethylene units, DGEBAEO-2) using hexahydrophthalic anhydride (HHPA) as curing agent and tris-(dimethylaminomethyl) phenol (DMP-30) as accelerator were comparatively studied by non-isothermal DSC with a model-fitting Málek approach and a model-free advanced isoconversional method of Vyazovkin. The dynamic mechanical properties and thermal stabilities of the cured materials were investigated by DMTA and TGA, respectively. The results showed that Šesták–Berggren model can generally simulate well the reaction rates of these two systems. The activation energy of DGEBA/DGEBD/HHPA/DMP-30 at high fractional conversion changed much higher than that of DGEBAEO-2/HHPA/DMP-30, indicating the increased steric hindrance mainly affected the reaction kinetic scheme of DGEBA/DGEBD/HHPA/DMP-30. The T{sub g} and storage moduli of cured DGEBAEO-2/HHPA/DMP-30 were lower than those of cured DGEBA/DGEBD/HHPA/DMP-30 according to DMTA while TGA showed that the thermal stabilities of these two cured systems were similar.

  18. Morphology and mechanical properties of poly(butylene adipate-co-terephthalate)/potato starch blends in the presence of synthesized reactive compatibilizer or modified poly(butylene adipate-co-terephthalate).

    Science.gov (United States)

    Wei, Dafu; Wang, Hao; Xiao, Huining; Zheng, Anna; Yang, Yang

    2015-06-01

    The biodegradable poly(butylene adipate-co-terephthalate)(PBAT)/thermoplastic starch (TPS) composite has received considerable attention because of the environmental concerns raised by solid waste disposal. However, the application of PBAT/TPS blends was limited due to the poor mechanical properties originating from the incompatibility between PBAT and TPS. In this work, two approaches were developed to improve the mechanical properties of PBAT/TPS blends. One approach is to use compatibilizers, including the synthesized reactive compatibilizer - a styrene-maleic anhydride-glycidyl methacrylate (SMG) terpolymer, and the commercial compatibilizer (Joncryl-ADR-4368). The chemical structures of SMG were analyzed with (1)H NMR and FT-IR. The other approach is to use the modified PBAT (M-PBAT) to replace part of PBAT in the PBAT/TPS blends. M-PBATs with higher molecular weight were obtained via reactive extrusion of PBAT in the presence of a chain extender. The better dispersion of TPS in PBAT was observed in SEM images when using M-PBAT, leading to the higher tensile strength and elongation at break of PBAT/TPS blends. However, the elongation at break decreased in the presence of compatibilizer (SMG or 4368), though the tensile strength remained in a similar level or slightly higher. Overall, the tensile strength and the elongation at break of the resulting biodegradable PBAT/M-PBAT/TPS blends (TPS=40wt%) were above 27.0MPa and 500%, respectively, which is promising for various applications, including packaging and agricultural mulching films.

  19. 40 CFR 721.6477 - Alkyl polycarboxylic acids, esters with ethoxylated fatty alcohols, reaction products with maleic...

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Alkyl polycarboxylic acids, esters... Alkyl polycarboxylic acids, esters with ethoxylated fatty alcohols, reaction products with maleic... identified generically as alkyl polycarboxylic acids, esters with ethoxylated fatty alcohols, reaction...

  20. Synthesis of Caffeine/Maleic Acid Co-crystal by Ultrasound-assisted Slurry Co-crystallization.

    Science.gov (United States)

    Apshingekar, Prafulla P; Aher, Suyog; Kelly, Adrian L; Brown, Elaine C; Paradkar, Anant

    2017-01-01

    A green approach has been used for co-crystallization of noncongruent co-crystal pair of caffeine/maleic acid using water. Ultrasound is known to affect crystallization; hence, the effect of high power ultrasound on the ternary phase diagram has been investigated in detail using a slurry co-crystallization approach. A systematic investigation was performed to understand how the accelerated conditions during ultrasound-assisted co-crystallization will affect different regions of the ternary phase diagram. Application of ultrasound showed considerable effect on the ternary phase diagram, principally on caffeine/maleic acid 2:1 (disappeared) and 1:1 co-crystal (narrowed) regions. Also, the stability regions for pure caffeine and maleic acid in water were narrowed in the presence of ultrasound, expanding the solution region. The observed effect of ultrasound on the phase diagram was correlated with solubility of caffeine and maleic acid and stability of co-crystal forms in water. Copyright © 2016. Published by Elsevier Inc.

  1. Synthesis of first row transition metal carboxylate complexes by ring opening reactions of cyclic anhydrides

    Indian Academy of Sciences (India)

    Jubaraj Bikash Baruah

    2011-03-01

    Hydrolytic and solvolytic ring opening reactions of phthalic anhydride, pyromellitic dianhydride and 2,3-pyridine dicarboxylic anhydride in the presence of various transition metal salts with or without a ancillary ligands were studied. The reactions were found to be dependent on stoichiometry of ligand and types of anhydride used. In the case of pyromellitic dianhydride selective ring opening reaction by cobalt(II) ions gave 1,3-benzene dicarboxylate derivatives, whereas use of copper(II) ions gave 1,4-benzene dicarboxylate derivatives. Preference for methanolysis was seen in the case of copper (II) promoted reactions of pyromellitic dianhydride in the presence of 1:1 metal to 1,10-phenanthroline ratio.

  2. The impact of epoxy acrylate-modified on the properties waterborne alkyd resin%环氧丙烯酸酯改性对水性醇酸树脂性能的影响∗

    Institute of Scientific and Technical Information of China (English)

    袁腾; 刘文济; 赵韬; 周显宏; 王锋; 涂伟萍

    2015-01-01

    以亚麻油、甘油、苯酐、顺酐为原料合成醇酸树脂,并利用环氧树脂、苯乙烯以及丙烯酸单体对所合成的醇酸树脂进行改性,得到一种环氧丙烯酸改性水性醇酸树脂。采用红外光谱表征了合成过程中每一步骤所得到的产物的结构,证明了成功在醇酸树脂链段上引入了改性链段;以热重分析和凝胶色谱考察了改性前后的醇酸树脂的性能,结果表明,偏酐与环氧丙烯酸改性后的醇酸树脂分子量及分散度都有所增加,其中环氧/AA/St改性的醇酸树脂分子量最大,分子量分布最宽,环氧/AA/St 改性的醇酸树脂耐热性能得到了改善。最后对漆膜性能进行比较,结果表明,在水分散性方面,环氧/AA/St 改性醇酸略弱于偏酐改性醇酸,产物粘度也相对较大,但是其稳定性、漆膜的附着力、耐水性以及耐盐水性能等与偏酐改性醇酸相比都明显得到了提高。%Waterborne alkyd resin(WAR )was synthesized by linsee d oil,glycerol,phthalic anhydride,maleic anhydride used as raw materials,while epoxy resin,styrene and acrylic monomers were used to modify the waterborne alkyd res-in,a epoxy acrylate modified waterborne alkyd resin was prepared.The structure of the products synthesized in each step were characterized with infrared spectroscopy,which proved that epoxy acrylate modified segment was introduced to the alkyd resin segment successfully.The properties of the waterborne alkyd resins before and after modified were stud-ied with Thermogravimetric Analysis and Gel Permeation Chromatography,the results showed that the molecular weight and the dispersity of the alkyd resin modified by TMA and epoxy acrylate had increased to some extent,respec-tively.the molecular weight of the alkyd resin modified by epoxy/AA/St was largest,and the molecular weight distri-bution was widest,while the heat resistance had improved greatly.Finally,the film properties of these three

  3. ULTRASONIC BEHAVIOR OF EPOXY RESINS/POLY (ETHYLENE OXIDE)BLENDS CURED WITH PHTHALIC ANHYDRIDE

    Institute of Scientific and Technical Information of China (English)

    ZHENG Sixun; WANG Haiqian; LUO Xiaolie; ZHANG Naibin; MA Dezhu; ZHU Changfei; HU Jiankai

    1995-01-01

    By means of ultrasonic attenuation apparatus, the ultrasonic velocity and attenuation of anhydride-cured epoxy resins (EP)/poly(ethylene oxide)(PEO)blends were measured on the basis of pulse-echo method. It was found that the sonic velocity of the blends decreased as the temperature increased, but attenuation coefficient increased and possessed a peak value. Larger velocity and smaller attenuation coefficient(α)can be obtained from perfect crosslinking network structures of pure DGEBA cured with phthalic anhydride (PA). As for cured DGEBA/PEO blend systems,sonic velocity decreased as a function of PEO concentration,but attenuation coefficient (α) increased.

  4. CATALYSIS OF POLYSTYRENE N-HYDROXYL SULFONAMIDE FOR ESTERIFICATION OF BUTANOL WITH ACETIC ANHYDRIDE

    Institute of Scientific and Technical Information of China (English)

    LI Shufeng; LI Qian; YANG Xinlin; HUANG Wenqiang

    2004-01-01

    Polystyrene N-hydroxyl sulfonamide resin 1 was prepared and used to catalyze the esterification of n-butanol and acetic anhydride. The mechanism of catalytic esterification proved by IR spectra of the resins was found that O-H and N-H of the N-hydroxyl sulfonamide resin reacted with the acetic anhydride respectively to form the active intermediate polystyrene N,O-diacetyl sulfonamate which was cleaved by n-butanol to produce butyl acetate. The catalytic esterification by resin 1 was in good agreement with the kinetic model of "bi-bi-ping-pong" mechanism.

  5. Preparation, characterization and luminescent properties of dense nano-silica hybrids loaded with 1,8-naphthalic anhydride.

    Science.gov (United States)

    Wang, Jinpeng; Sun, Jihong; Li, Yuzhen; Wang, Feng

    2014-03-01

    Novel luminescent dense nano-silica hybrid materials (DNSS) modified with different amounts of (3-aminopropyl)triethoxysilane (APTES) and 1,8-naphthalic anhydride (NA) were successfully synthesized via two steps combined with post-grafting methods. Powder X-ray diffraction (XRD), N2-sorption analysis, Fourier transform infrared (FT-IR) spectroscopy, transmission electron microscopy (TEM), thermogravimetric analysis (TGA), photoluminescence (PL) spectroscopy and elemental analysis, as well as time-resolved decays were employed to characterize the resultant hybrid materials. The results revealed that luminescent organic molecules had been successfully loaded onto the amine-modified surface of nano-silica spheres. In addition, their fluorescence intensity and characteristic peak of emission spectra changed with increasing amount of APTES and NA additive. In particular, the characteristic peak showed a red shift from 390 to 450 nm, however, this was inconsistent with results calculated on the basis of the elemental analysis data, most probably because of the dispersion behaviors of NA molecules from the aggregating to the monolayer state. These observations demonstrated the existence of a quantum confinement effectiveness of NA-DNSS samples, and therefore a possible mechanism was put forward.

  6. The guanidine and maleic acid (1:1) complex. The additional theoretical and experimental studies

    Science.gov (United States)

    Drozd, Marek; Dudzic, Damian

    2012-04-01

    On the basis of experimental literature data the theoretical studies for guanidinium and maleic acid complex with using DFT method are performed. In these studies the experimental X-ray data for two different forms of investigated crystal were used. During the geometry optimization process one equilibrium structure was found, only. According to this result the infrared spectrum for one theoretical molecule was calculated. On the basis of potential energy distribution (PED) analysis the clear-cut assignments of observed bands were performed. For the calculated molecule with energy minimum the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) were obtained and graphically illustrated. The energy difference (GAP) between HOMO and LUMO was analyzed. Additionally, the nonlinear properties of this molecule were calculated. The α and β (first and second order) hyperpolarizability values are obtained. On the basis of these results the title crystal was classified as new second order NLO generator.

  7. Triflic Anhydride-Mediated Beckmann Rearrangement Reaction of Β-Oximyl Amides: Access to 5-Iminooxazolines

    Indian Academy of Sciences (India)

    MANGFEI YU; QIAN ZHANG; JIA WANG; PENG HUANG; PENGFEI YAN; RUI ZHANG; DEWEN DONG

    2016-06-01

    Facile and efficient synthesis of 5-iminooxazolines fromΑ, Α-disubstituted Β-oximyl amidesmediated by triflic anhydride $(Tf_{2}O)$ in the presence of 1,8-diazabicyclo(5.4.0)undec-7-ene (DBU) indichloromethane at room temperature is developed, and a mechanism involving tandem Beckmann rearrangementand intramolecular cyclization reaction is proposed.

  8. Molecular characterization of trimellitic anhydride-induced respiratory allergy in Brown Norway rats

    NARCIS (Netherlands)

    Kuper, C.F.; Heijne, W.H.; Dansen, M.; Verhoeckx, K.C.; Boorsma, A.; Radonjic, M.; Bruijntjes, J.; Stierum, R.; Muijser, H.; Arts, J.H.

    2008-01-01

    To contribute to the hazard identification of low molecular weight (LMW) respiratory allergens, respiratory allergy induced by trimellitic anhydride (TMA) was characterized by whole genome analysis of lung tissue and blood proteomics in Brown Norway rats. Dermal sensitization (50% and 25% w/v) with

  9. Controlled release from aspirin based linear biodegradable poly(anhydride esters) for anti-inflammatory activity.

    Science.gov (United States)

    Dasgupta, Queeny; Movva, Sahitya; Chatterjee, Kaushik; Madras, Giridhar

    2017-08-07

    This work reports the synthesis of a novel, aspirin-loaded, linear poly (anhydride ester) and provides mechanistic insights into the release of aspirin from this polymer for anti-inflammatory activity. As compared to conventional drug delivery systems that rely on diffusion based release, incorporation of bioactives in the polymer backbone is challenging and high loading is difficult to achieve. In the present study, we exploit the pentafunctional sugar alcohol (xylitol) to provide sites for drug (aspirin) attachment at its non-terminal OH groups. The terminal OH groups are polymerized with a diacid anhydride. The hydrolysis of the anhydride and ester bonds under physiological conditions release aspirin from the matrix. The resulting poly(anhydride ester) has high drug loading (53%) and displays controlled release kinetics of aspirin. The polymer releases 8.5 % and 20%, of the loaded drug in one and four weeks, respectively and has a release rate constant of 0.0035h(-0.61). The release rate is suitable for its use as an anti-inflammatory agent without being cytotoxic. The polymer exhibits good cytocompatibility and anti-inflammatory properties and may find applications as injectable or as an implantable bioactive material. The physical insights into the release mechanism can provide development of other drug loaded polymers. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. SELECTIVE HYDROGENATION OF ANHYDRIDES TO LACTONES UNDER SUPERCRITICAL CARBON DIOXIDE MEDIUM

    Science.gov (United States)

    Selective Hydrogenation of Anhydrides to Lactones Under Supercritical Carbon Dioxide MediumEndalkachew Sahle-Demessie Unnikrishnan R PillaiU.S. EPA , 26 W. Martin Luther King Dr. Cincinnati, OH 45268 Phone: 513-569-7739Fax: 513-569-7677Abstract:Hydrogenat...

  11. TRIMELLITIC ANHYDRIDE (TMA) HYPERSENSITIVITY IN MICE AFTER MULTIPLE INTRATRACHAEL (IT) EXPOSURE

    Science.gov (United States)

    SOT 2001 DMS214TRIMELLITIC ANHYDRIDE (TMA) HYPERSENSITIVITY INMICE AFTER MULTIPLE INTRATRACHEAL (IT) EXPOSURES. D Sailstad, E Boykin, M Ward, and MJ Selgrade. NHEERL, ORD, US EPA, RTP, NC, USA.TMA causes Th2 related respiratory hypersensitivity (RH) responses. W...

  12. Study of Swelling Properties and Thermal Behavior of Poly(N,N-Dimethylacrylamide-co-Maleic Acid Based Hydrogels

    Directory of Open Access Journals (Sweden)

    Sadjia Bennour

    2014-01-01

    Full Text Available Hydrogels copolymers N,N-dimethylacrylamide (DMA and maleic acid (MA were prepared by free-radical polymerization at 56°C in aqueous solution, using N,N-methylenebisacrylamide (NMBA as cross-linking agent and potassium persulfate (KPS as initiator. The effects of comonomer composition, cross-linker content, and variation of pH solutions on the swelling behavior of polymers were investigated. The obtained results showed an increase of the swelling of poly(N,N-dimethylacrylamide-co-maleic acid (P(DMA-MAx as the content of maleic acid increases in the polymeric matrix, while they indicate a great reduction of the degree of swelling as the cross-linking agent ratio increases. It was also shown that the swelling of copolymer hydrogels increased with the increase of pH and the maximum extent was reached at pH 8.7 in all compositions. Fourier transform infrared spectroscopy (FTIR revealed the existence of hydrogen bonding interactions between the carboxylic groups of MA and the carbonyl groups of DMA. Differential scanning calorimetry analysis (DSC showed an increase of the glass-transition temperature (Tg as concentrations of MA and NMBA increased. Thermogravimetric analysis (TGA of copolymers was performed to investigate the degradation mechanism.

  13. Membrane protein extraction and purification using styrene-maleic acid (SMA) copolymer: effect of variations in polymer structure.

    Science.gov (United States)

    Morrison, Kerrie A; Akram, Aneel; Mathews, Ashlyn; Khan, Zoeya A; Patel, Jaimin H; Zhou, Chumin; Hardy, David J; Moore-Kelly, Charles; Patel, Roshani; Odiba, Victor; Knowles, Tim J; Javed, Masood-Ul-Hassan; Chmel, Nikola P; Dafforn, Timothy R; Rothnie, Alice J

    2016-12-01

    The use of styrene-maleic acid (SMA) copolymers to extract and purify transmembrane proteins, while retaining their native bilayer environment, overcomes many of the disadvantages associated with conventional detergent-based procedures. This approach has huge potential for the future of membrane protein structural and functional studies. In this investigation, we have systematically tested a range of commercially available SMA polymers, varying in both the ratio of styrene and maleic acid and in total size, for the ability to extract, purify and stabilise transmembrane proteins. Three different membrane proteins (BmrA, LeuT and ZipA), which vary in size and shape, were used. Our results show that several polymers, can be used to extract membrane proteins, comparably to conventional detergents. A styrene:maleic acid ratio of either 2:1 or 3:1, combined with a relatively small average molecular mass (7.5-10 kDa), is optimal for membrane extraction, and this appears to be independent of the protein size, shape or expression system. A subset of polymers were taken forward for purification, functional and stability tests. Following a one-step affinity purification, SMA 2000 was found to be the best choice for yield, purity and function. However, the other polymers offer subtle differences in size and sensitivity to divalent cations that may be useful for a variety of downstream applications. © 2016 The Author(s); published by Portland Press Limited on behalf of the Biochemical Society.

  14. Linear, Mannitol-Based Poly(anhydride-esters) with High Ibuprofen Loading and Anti-Inflammatory Activity.

    Science.gov (United States)

    Stebbins, Nicholas D; Yu, Weiling; Uhrich, Kathryn E

    2015-11-09

    Sugar alcohols, such as mannitol and xylitol, are biocompatible polyols that have been used to make highly cross-linked polyester elastomers and dendrimers for tissue engineering and drug delivery. However, research that utilizes the secondary hydroxyl groups as sites for pendant bioactive attachment and subsequent polymerization is limited. This work is the first report of a linear, completely biodegradable polymer with a sugar alcohol backbone and chemically incorporated pendant bioactives that exhibits sustained bioactive release and high bioactive loading (∼70%). With four pendant esters per repeat unit, this poly(anhydride-ester) has high loading and biodegrades into three biocompatible products: bioactive, sugar alcohol, and alkyl-based diacid. Ibuprofen serves as a representative bioactive, whereas mannitol is a representative polyol. Polymerization was achieved through reaction with (trimethylsilyl)ethoxyacetylene. Drug release via polymer degradation was quantified by high performance liquid chromatography. Additionally, a cytocompatibility study with fibroblast cells was performed to elucidate the polymer's suitability for in vivo use and a cyclooxygenase-2 (COX-2) assay was performed on the degradation media to ensure that released ibuprofen retained its anti-inflammatory activity. This work enables the future development of novel, biodegradable polymers exhibiting two key features: (i) polymer backbones with easily modified pendant groups, such as targeting moieties, and (ii) high drug loading using a multitude of bioactive classes.

  15. Preparation and characterization of new succinic anhydride grafted Posidonia for the removal of organic and inorganic pollutants

    Energy Technology Data Exchange (ETDEWEB)

    Chadlia, Aguir, E-mail: aguirc@yahoo.ca [Unite de Recherche de Chimie Appliquee et Environnement, Faculte des Sciences de Monastir, 5000 (Tunisia); Mohamed, Khalfaoui [Unite de Recherche de Physique Quantique, Faculte des Sciences de Monastir, 5000 (Tunisia); Najah, Laribi; Farouk, M' henni Mohamed [Unite de Recherche de Chimie Appliquee et Environnement, Faculte des Sciences de Monastir, 5000 (Tunisia)

    2009-12-30

    The present work describes the preparation of new chelating materials derived from Posidonia for adsorption of heavy metal ions and dye in aqueous solution. The first part of this report deals with the chemical modification of Posidonia with succinic anhydride. Thus, we have obtained materials with various succinyl groups contents (from 29.8 to 39.2%). The obtained materials were characterized by infrared and CP/MAS {sup 13}C-RMN spectroscopy. The rate of succinyl content of the modified Posidonia was determined by saponification. The second part is devoted to the evaluation of the adsorption capacity of metal ions such as Pb{sup 2+} and dye such as direct red 75 (DR75) for raw and modified Posidonia materials. Two possible ways for the adsorption of these pollutants are studied: adsorption of each pollutant alone onto these supports, and cumulative adsorption of both metal ions and dye on the same supports. In the last case, the pollutant is adsorbed successively from two different solutions. The effects of pollutants concentration, support dose, pH, contact time and temperature on adsorption of each pollutant were evaluated. The results showed that the raw and modified Posidonia show a high capacity for Pb{sup 2+} adsorption. The capacity of modified Posidonia saturated with Pb{sup 2+} to adsorb DR75 was found 147.12 mg g{sup -1}. While the adsorption capacity of the nonsaturated modified Posidonia was equal to 81.63 mg g{sup -1}. The pseudo-second-order model was the best to represent adsorption kinetics of DR75. The pseudo-first-order model would be better for fitting the adsorption kinetic process of Pb{sup 2+} onto raw and modified Posidonia. The adsorption isotherms of Pb{sup 2+} could be described by the Jossens equation model. Any of the tested models can describe the adsorption of DR75 onto the studied materials. These results confirm that the adsorption of DR75 from aqueous solution was multilayer.

  16. Facile and Efficient Acetylation of Primary Alcohols and Phenols with Acetic Anhydride Catalyzed by Dried Sodium Bicarbonate

    National Research Council Canada - National Science Library

    Fulgentius Nelson Lugemwa; Koonj Shaikh; Edwin Hochstedt

    2013-01-01

      A variety of primary alcohols and phenols were reacted with acetic anhydride at room temperature in the presence of sodium bicarbonate to produce corresponding esters in good to excellent yields...

  17. Ruthenium-catalyzed decarbonylative addition reaction of anhydrides with alkynes: a facile synthesis of isocoumarins and α-pyrones.

    Science.gov (United States)

    Prakash, Rashmi; Shekarrao, Kommuri; Gogoi, Sanjib; Boruah, Romesh C

    2015-06-21

    A novel ruthenium catalyzed straightforward and efficient synthesis of isocoumarin and α-pyrone derivatives has been accomplished by the decarbonylative addition reaction of anhydrides with alkynes under thermal conditions.

  18. Kinetics and Mechanism for Formation of Olefin Complexes in the Reaction between Palladium(II) and Maleic Acid.

    Science.gov (United States)

    Shi, Tiesheng; Elding, Lars I.

    1998-10-19

    Complex formation between Pd(H(2)O)(4)(2+) and maleic acid (H(2)A) has been studied at 25 degrees C and 2.00 M ionic strength in acidic aqueous solution. Reaction takes place with 1:1 stoichiometry. The kinetics has been followed by use of stopped-flow spectrophotometry under pseudo-first-order conditions with maleic acid in excess. In the concentration ranges 0.01 C where, in addition, both steps contain contributions from parallel reactions. The amplitude of the first phase increases with increasing [H(2)A](tot) and with decreasing [H(+)]. Multiwavelength global analysis of the kinetic traces and the UV-vis spectral changes suggest that a monodentate oxygen-bonded hydrogen maleate complex, [Pd(H(2)O)(3)OOCCH=CHCOOH](+), B, with stability constant K(2) = 205 +/- 40 M(-)(1) is formed as an intermediate in this first step via two parallel reversible reactions in which Pd(H(2)O)(4)(2+) reacts with maleic acid and hydrogen maleate, respectively. In the following step, B --> C, slow intramolecular ring closure with a rate constant of 0.8 +/- 0.1 s(-)(1) at 25 degrees C gives the reaction product C, which is concluded to be a 4.5-membered olefin-carboxylato chelate complex on the basis of stoichiometry and UV-vis/NMR spectra. Parallel and irreversible attack by maleic acid and hydrogen maleate acting as olefins on the intermediate B also leads to formation of C. C is stable for at least 20 h for concentrations of maleic acid. Neither a steady-state approximation nor a rapid preequilibrium assumption can be used for the kinetics data treatment. Exact rate expressions for the fast and slow phases have been used to derive all rate constants involved. Olefins are inefficient nucleophiles toward palladium(II), even less efficient than carboxylic acids and carboxylates.

  19. 聚乙烯熔融法接枝马来酸酐的制备及表征%Preparation of Maleic Anhydride Grafted Polyethylene Using Melt Method and Its Characterization

    Institute of Scientific and Technical Information of China (English)

    禄秋艺; 罗筑; 杨乐; 娄金分

    2014-01-01

    研究了加工工艺及环氧树脂的加入对聚乙烯接枝马来酸酐(PE-g-MAH)接枝反应的影响.结果表明:当引发剂浓度较低时,随着温度的提高,PE-g-MAH的接枝率增大,但其熔体流动速率降低;引发剂用量超过0.5 phr后,随着温度的提高,PE-g-MAH的接枝率及熔体流动速率基本保持不变.随着环氧树脂用量的增加,PE-g-MAH的接枝率增大,当环氧树脂用量为1.2 phr时,接枝率达到量大,熔体流动速率降至最低.环氧树脂的加入促进了马来酸酐的接枝,在PE大分子链上引入了新的极性基团.与PE相比,PE-g-MAH的结晶峰温提高,结晶度降低.

  20. EFFECT OF MALEIC ANHYDRIDE-GRAFTED ON COMPATIBILITY OF PP/PA6 BLENDS%马来酸酐接枝物对PE/PA6共混物相容性的影响

    Institute of Scientific and Technical Information of China (English)

    伍玉娇; 王珏; 杨红军; 骆丁胜; 丁兴艳

    2007-01-01

    采用熔融共混法制备了PP/PA6/POE-g-MAH和PP/PA6/PP-g-MAH共混物.通过扫描电子显微镜(SEM)、差示扫描量热(DSC)仪分析和力学性能测试研究了增容剂POE-g-MAH和PP-g-MAH对PP/PA6共混物相容性、形态结构和宏观力学性能的影响.结果表明,在PP/PA6共混体系中分别加入POE-g-MAH和PP-g-MAH不仅能显著改善两相界面的相容性,减小分散相的粒径,而且能使共混物的力学性能显著提高.当增客剂的用量为5份时,PP/PA6共混物有较好的综合力学性能.POE-g-MAH和PP-g-MAH增容PP/PA6共混体系非等温结晶行为的研究表明,POE-g-MAH和PP-g-MAH均能促进PA6对PP基体的异相成核作用.

  1. Study on PA66/EVA Copolymer Grafted Maleic Anhydride Blends%尼龙/乙烯-醋酸乙烯酯共聚物接枝马来酸酐共混体系的研究

    Institute of Scientific and Technical Information of China (English)

    张军; 陈民杰; 万吴军; 殷会玉

    2003-01-01

    通过双螺杆挤出机利用熔融挤出法制备了增韧的尼龙66/乙烯-醋酸乙烯酯共聚物接枝马来酸酐共混物(PA66/EVA-g-MAH).实验结果表明,未经接枝改性的EVA与PA66是不相容的,对增韧PA66几乎没有贡献,而EVA-g-MAH则出现了明显的增韧效果.在熔融挤出过程中,PA66与EVA-g-MAH发生了原位化学反应,生成了PA66-EVA共聚物.这种共聚物细化了分散相尺寸,使得分散相在PA66基体中分散得更均匀,提高了两相的相容性.同时增强了两相界面间的结合力,使得应力能够在两相间有效地传递,这种界面形态的改善直接影响到共混物力学性能的变化.随着EVA-g-MAH含量的增加,PA66/EVA-g-MAH共混物的冲击强度提高,当PA66/EVA-g-MAH的共混比为70/30(质量比)时,体系发生了脆韧转变,冲击强度达到了最大,比纯PA66、PA66/EVA(70/30)共混物提高了12倍.和PE-g-MAH、PP-g-MAH相比,EVA-g-MAH对PA66的增韧效果最好.

  2. Study on aluminum pigment encapsulated by in situ copolymerization of styrene-maleic anhydride%苯乙烯-马来酸酐原位共聚包覆铝颜料的研究

    Institute of Scientific and Technical Information of China (English)

    刘辉; 叶红齐; 林丹; 何显达

    2007-01-01

    研究了苯乙烯-马来酸酐原位共聚包覆铝颜料的最佳反应条件,探讨了m(St+MAn)/m(Al)对颜料铝粉耐腐蚀性能与光泽度的影响.结果表明,最佳反应条件是:反应温度为80℃;反应时间为4h;引发剂用量为0.075g;n(St)∶n(MAn)为1∶1.当m(St+MAn)/m(Al)为0.1时,包覆得到的产物同时具有良好的光泽度与耐腐蚀性.运用IR、光学显微镜、SEM、粒度分析等手段对包覆样品进行了分析与表征.

  3. The Graft Copolymer of Low-Density Polyethylene with Maleic Anhydride and Their Polyblend with Kaolin%低密度聚乙烯接枝马来酸酐及与高岭土复合

    Institute of Scientific and Technical Information of China (English)

    苏介生; 林松柏

    1993-01-01

    研究低密度聚乙烯接枝马来酸酐,其接枝物用红外光谱证实.用正交设计法研究接枝物的接枝度与单体、溶剂、引发剂、反应时间和温度的影响规律,找出最佳接枝条件.对接枝物与定量高岭土进行复合,初步探讨它们与抗张强度的关系.

  4. Study on grafting of polyethylene wax with maleic anhydride by melting method%熔融法聚乙烯蜡接枝马来酸酐的研究

    Institute of Scientific and Technical Information of China (English)

    马宇辉; 王桂香; 禹雪晴; 张端; 王润珩

    2003-01-01

    研究了熔融法聚乙烯蜡接枝马来酸酐的工艺过程和影响反应的主要因素.以丙酮为溶剂,将MAH和聚合引发剂配成溶液滴加反应,引发剂和MAH的质量分数各为12%,反应温度165 ℃左右,接枝率可达15.6%.经红外谱图分析证明聚乙烯蜡与马来酸酐发生了接枝反应.在热熔胶的制备中,发现使用接枝聚乙烯蜡比使用未接枝聚乙烯蜡的粘接强度(PVC/木材)提高了约90%.

  5. 聚乙烯马来酸酐接枝物合成环氧树脂的研究%Study on synthesis of epoxy resin from polyethylene grafted maleic anhydride

    Institute of Scientific and Technical Information of China (English)

    苏桂明; 刘津瑞; 关建宁; 魏无际; 龚丽芳

    2010-01-01

    以低密度聚乙烯接枝马来酸酐(LDPE-g-MAH)为原料与环氧氯丙烷反应合成一种以聚乙烯为主要结构的固态环氧树脂-聚乙烯酯型环氧树脂(LDPE-g-MAH-g-ECH),并利用FT-IR光谱表征了该环氧树脂的化学结构.采用化学分析法研究了反应物料配比、反应温度、反应时间、催化剂用量、碱的用量与浓度等因素对合成反应的影响,确定了合成该环氧树脂的最佳反应条件.该树脂为淡褐色透明粉末,采用化学分析方法测得其环氧值0.24~0.27mmol/g,酸值<0.5mg/g.

  6. Application of Ultrasonc Wave to Study of PP and Maleic Anhydride Solid-grafting%超声波在聚丙烯固相接枝马来酸酐研究中的应用

    Institute of Scientific and Technical Information of China (English)

    杜慷慨; 吴翠玲

    2000-01-01

    本文利用超声波的分散原理,研究聚丙烯(PP)固相接枝马来酸酐(MAH)的反应,考察反应温度,超声波作用时间,过氧化苯甲酰(BPO)用量,MAH使用量等因素对接枝率的影响,并用红外光谱对接枝产物加以证实.结果表明,PP固相接枝MAH反应:随着温度的升高、超声波作用时间的延长、MAH用量的增加,接枝率提高;随着BPO用量的增加,接枝率先增加,后略有降低.在实验条件下,可得到接枝率为8.5%的PP-MAH接枝产物.

  7. Development and Application of Stearic Acid Diethanolamide Acrylate Ester/Styrene/Maleic Anhydride (SSM) Copolymer as Diesel Depressant%SSM共聚物柴油降凝剂的研制及应用

    Institute of Scientific and Technical Information of China (English)

    赵晓非; 毕立娜; 王晶镱; 田春雨; 李贵学

    2009-01-01

    采用溶液聚合法合成降凝剂,研究了单体配比、引发剂用量、聚合温度和聚合时间对聚合物助滤效果的影响.红外光谱对化合物的分子结构进行了表征,结果表明,合成的分子结构和设计目标分子结构相符.此降凝剂可使大庆0#柴油的凝点降低6℃,对其他柴油也有一定的降凝效果.

  8. The effect of active carbon to Cu/ZnO catalyst of maleic anhydride hydrogenation%活性炭对顺酐加氢催化剂Cu/ZnO的影响

    Institute of Scientific and Technical Information of China (English)

    陈亿新; 王江兵; 古凤强; 陈国术; 陈胜洲; 刘自力

    2011-01-01

    研究了Cu/ZnO、Cu/ZnO-C和Cu/ZnO-Al2O3 催化剂.采用XRD、TPR、BET、SEM等方法对催化剂进行表征,考察了它们的催化反应性能,发现Cu/Zn0催化剂中添加活性炭可以使顺酐气相加氢合成γ-丁内酯(GBL)的反应温度降低.在250℃,液体空速为0.1 h-1,氢酐摩尔比为50:1的条件下,顺酐转化率达到100%,GBL选择性超过90%.对Cu/ZnO-C催化剂的失活因素进行了分析,结果表明,催化剂的烧结与积炭是导致催化剂失活的主要原因.

  9. 顺酐加氢合成γ-丁内酯的Cu-ZnO/C催化剂研究%Study on Cu-Zno/C Catalysts for Maleic Anhydride Hydrogenation to γ-Butyrolactone

    Institute of Scientific and Technical Information of China (English)

    王江兵; 古凤强; 梁海波; 周美兰; 陈国术; 陈亿新

    2010-01-01

    采用XRD、TPR、BET等方法对几种Cu/Zn催化剂进行表征,考察了催化剂活性与寿命.发现Cu/Zn催化剂添加活性炭可使顺酐常压气相加氢合成γ-丁内酯(GBL)的反应温度降低至240℃.在优化条件下:液体空速为0.1 h-1,氢酐摩尔比为50:1,顺酐转化率100%,GBL选择性为93.28%,催化剂寿命达2 000 h以上.

  10. Research on Non-noble Metal/Palladium Catalyst for Hydrogenation of Maleic Anhydride%非贵金属/钯顺酐加氢催化剂的研究

    Institute of Scientific and Technical Information of China (English)

    张建国; 王海京; 阮济之

    2003-01-01

    以γ-丁内酯(GBL)为模型化合物,考察了Cu、Zn、Mn、Al 4种非贵金属元素对Pd系顺酐加氢催化剂在中压条件下对GBL和顺酐(MA)加氢的影响,发现4种非贵金属元素的组合加入对Pd系顺酐加氢催化剂的加氢性能有显著影响,其中Mn、Al的加入有利于提高催化剂的加氢活性,Cu、Zn的加入有利于提高GBL到四氢呋喃(THF)的转化.研制的PdCuZnMnAl/C催化剂在6.0 MPa的中压条件下,对顺酐进行加氢,MA转化率为100%,THF选择性达72.8%.催化剂的TEM、XRD、XPS分析表明非贵金属Cu、Zn、Mn、Al和贵金属Pd之间有明显的相互作用.

  11. SMA增容吸水膨胀橡胶的制备及其性能%Preparation and properties of a water-swellable rubber compatibilized by styrene-maleic anhydride copolymer

    Institute of Scientific and Technical Information of China (English)

    辛华; 马凤博; 田凯; 赵星; 朱万诚

    2016-01-01

    以自制苯乙烯-马来酸酐共聚物SMA为增容剂,通过物理方法将吸水树脂PAAS与氯丁橡胶CR共混制备吸水膨胀橡胶WSR.重点研究PAAS用量、SMA用量、S用量对WSR主要性能指标(吸水倍率及其力学性能)的影响,结果表明:WSR吸水能力随着PAAS用量增大而提高,随着SMA、S用量的增大先提高后降低;WSR力学性能随着PAAS、SMA、S用量增大先增强后降低;在本研究体系中,三者较佳的用量为30 phr、5 phr、1 phr.硫化胶断面扫描电镜观察表明SMA在CR和PAAS两组分间起到了良好的增容作用.

  12. THE EFFECT OF MALEIC ANHYDRIDE GRAFTING RATIO OF POE ON TOUGHNESS OF PA11/POE/POE- G-MAH BLENDS%接枝率对尼龙11/POE/POE-g-MAH韧性的影响

    Institute of Scientific and Technical Information of China (English)

    高彧; 吕坤; 李齐方

    2001-01-01

    研究了含不同马来酸酐接枝率的POE-g-MAH对尼龙11/POE/POE-g-MAH(POE为乙烯-辛烯共聚物)共混物的影响,考察了共混物的缺口冲击强度.结果表明:增加POE-g-MAH的用量可以提高共混物的缺口冲击强度;共混物缺口冲击强度与POE的马来酸酐接枝率密切相关,缺口冲击强度随着接枝率的增大而增大;共混物的缺口冲击强度和马来酸酐接枝率之间的变化关系在较宽的温度范围内(-40℃~25℃)存在.

  13. The Use of Maleic Hydrazide for Effective Hybridization of Setaria viridis.

    Directory of Open Access Journals (Sweden)

    Govinda Rizal

    Full Text Available An efficient method for crossing green foxtail (Setaria viridis is currently lacking. S. viridis is considered to be the new model plant for the study of C4 system in monocots and so an effective crossing protocol is urgently needed. S. viridis is a small grass with C4-NADP (ME type of photosynthesis and has the advantage of having small genome of about 515 Mb, small plant stature, short life cycle, multiple tillers, and profuse seed set, and hence is an ideal model species for research. The objectives of this project were to develop efficient methods of emasculation and pollination, and to speed up generation advancement. We assessed the response of S. viridis flowers to hot water treatment (48°C and to different concentrations of gibberellic acid, abscisic acid, maleic hydrazide (MH, and kinetin. We found that 500 μM of MH was effective in the emasculation of S. viridis, whilst still retaining the receptivity of the stigma to pollination. We also report effective ways to accelerate the breeding cycle of S. viridis for research through the germination of mature as well as immature seeds in optimized culture media. We believe these findings will be of great interest to researchers using Setaria.

  14. The Use of Maleic Hydrazide for Effective Hybridization of Setaria viridis.

    Science.gov (United States)

    Rizal, Govinda; Karki, Shanta; Garcia, Richard; Larazo, Nikki; Alcasid, Michael; Quick, William Paul

    2015-01-01

    An efficient method for crossing green foxtail (Setaria viridis) is currently lacking. S. viridis is considered to be the new model plant for the study of C4 system in monocots and so an effective crossing protocol is urgently needed. S. viridis is a small grass with C4-NADP (ME) type of photosynthesis and has the advantage of having small genome of about 515 Mb, small plant stature, short life cycle, multiple tillers, and profuse seed set, and hence is an ideal model species for research. The objectives of this project were to develop efficient methods of emasculation and pollination, and to speed up generation advancement. We assessed the response of S. viridis flowers to hot water treatment (48°C) and to different concentrations of gibberellic acid, abscisic acid, maleic hydrazide (MH), and kinetin. We found that 500 μM of MH was effective in the emasculation of S. viridis, whilst still retaining the receptivity of the stigma to pollination. We also report effective ways to accelerate the breeding cycle of S. viridis for research through the germination of mature as well as immature seeds in optimized culture media. We believe these findings will be of great interest to researchers using Setaria.

  15. Covalent Immobilization of Lipase on Poly ( acrylonitrile-co-maleic acid) Ultrafiltration Hollow Fiber Membrane

    Institute of Scientific and Technical Information of China (English)

    YE Peng; XU Zhi-kang; WU Jian; DENG Hong-tao; SETA Patrick

    2005-01-01

    Lipase from Candida rugosa was covalently immobilized on the surface of an ultrafiltration hollow fiber membrane fabricated from poly (acrylonitrile-co-maleic acid) (PANCMA) in which the carboxyl groups were activated with 1-ethyl-3-(dimethylaminopropyl) carbodiimide hydrochloride (EDC) and dicyclohexyl carbodiimide (DCC)/N-hydroxyl succinimide(NHS), respectively. The properties of the immobilized lipase were assayed and compared with those of the free enzyme. The maximum activities were observed in a relatively broader pH value range at high temperatures for the immobilized lipase compared to the free one. It was also found that the thermal and pH stabilities of lipase were improved upon immobilization and at 50 ℃ the thermal inactivation rate constant values are 2.1×10-2 for the free lipase, 3.2×10-3 for the immobilized lipase on the EDC-activated PANCMA membrane and 3.5×10-3 for the immobilized lipase on the DCC/NHS-activated PANCMA membrane, respectively.

  16. Polymorphs of acyclovir-maleic acid salt and their reversible phase transition

    Science.gov (United States)

    Wang, Lianyan; Zhao, Yumei; Zhang, Zhengfeng; Wang, Jianming; Wang, Qiang; Zheng, Zhibing; Deng, Zongwu; Zhang, Hailu

    2017-01-01

    Acyclovir is a commonly used antiviral drug while its solubility is far from satisfied. It was reported that 1:1 acyclovir-maleic acid salt (ACV-MAL) possesses much higher maximum apparent solubility. In this contribution, a new crystal structure of ACV-MAL was solved at room temperature. This new crystal structure and previously reported structure at low temperature can transform to each other via a reversible solid phase transformation, which has been confirmed by single-crystal X-ray diffraction, solid state NMR and cycling differential scanning calorimetry tests. The phase change temperature is ca. 283-293 K (10-20 °C), which is slightly lower than room temperature (298 ± 2 K/25 ± 2 °C), but is in the range of ambient temperature. This kind of near room temperature phase transformation is less concerned and tends to be neglected. This case report reminds that more attention should be paid to the polymorphism of pharmaceuticals at such temperature range due to its fundamental and practical significance.

  17. 1-Butyl-3-methylimidazolium Salts as New Catalysts to Produce Epoxy-anhydride Polymers with Improved Properties

    OpenAIRE

    Mikhail S. Fedoseev; Gruzdev, Matvey S.; Lubov F. Derzhavinskaya

    2014-01-01

    We report the curing process of epoxy oligomers by using isomethyltetrahydrophthalic anhydride catalyzed with 1-butyl-3-methylimidazolium salts. Catalytic action has been ascertained to be dependent on the nature of anion. Salts with (Br-) and (PO4-) anions appeared to be most active. Formation of salt adducts with epoxy resin and anhydride is shown. Polymers having higher values of strength and glass transition temperature—as compared with similar epoxy systems cured in the presence of terti...

  18. Electron paramagnetic resonance and FT-IR spectroscopic studies of glycine anhydride and betaine hydrochloride

    Science.gov (United States)

    Halim Başkan, M.; Kartal, Zeki; Aydın, Murat

    2015-12-01

    Gamma irradiated powders of glycine anhydride and betaine hydrochloride have been investigated at room temperature by electron paramagnetic resonance (EPR). In these compounds, the observed paramagnetic species were attributed to the R1 and R2 radicals, respectively. It was determined that the free electron interacted with environmental protons and 14N nucleus in both radicals. The EPR spectra of gamma irradiated powder samples remained unchanged at room temperature for two weeks after irradiation. Also, the Fourier Transform Infrared (FT-IR), FT-Raman and thermal analyses of both compounds were investigated. The functional groups in the molecular structures of glycine anhydride and betaine hydrochloride were identified by vibrational spectroscopies (FT-IR and FT-Raman).

  19. Preparation and Physical Properties of Chitosan Benzoic Acid Derivatives Using a Phosphoryl Mixed Anhydride System

    Directory of Open Access Journals (Sweden)

    Kyu Yun Chai

    2012-02-01

    Full Text Available Direct benzoylation of the two hydroxyl groups on chitosan was achieved using a phosphoryl mixed anhydride system, derived from trifluoroacetic anhydride (TFAA, benzoic acids (BAs, and phosphoric acid (PA. The reaction is operated as a one pot process under mild conditions that does not require neither an inert atmosphere nor dry solvents. The structures of the synthesized compounds were confirmed by NMR and IR spectroscopy. Solubility tests on the products revealed that they were soluble in organic solvents such as N,N-dimethylformamide (DMF, dimethylsulfoxide (DMSO, and acetone. In the meantime, a morphological study by scanning electron microscopy (SEM evidently indicated that the chitosan benzoates underwent significant structural changes after the benzoylation.

  20. Effect of Hyperbranched Polyester on Modification of Epoxy Resins Cured with Anhydride

    Institute of Scientific and Technical Information of China (English)

    Xiu Xia WANG; Zhi Gang JIANG; Yi Feng ZHANG

    2006-01-01

    The synthesis and characterization of hyperbranched polyester (HBP) with different molecular weight are studied. The effect of HBP on the modification of epoxy resins cured with anhydride is mainly discussed. The characteristics of HBP and the morphologies of cured system are determined by nuclear magnetic resonance spectroscopy (NMR), gel permeation chromatography (GPC) and scanning electron microscope (SEM). The impact strength of cured system is detected and Fourier transform infrared (FTIR) measurements were used to pursue the curing process. The investigation shows that HBP can improve the toughness by forming copolymer networks between epoxy resins, HBP and anhydride. Moreover, when the molecular weight of HBP is 1342g/mol the toughening effect is the best, and the changes of toughness are small with the increase of molecular weight of HBP to 3500 g/mol.

  1. PLA branching with anhydrides and tri-functional aziridine

    Science.gov (United States)

    Gu, Liangliang; Xu, Yuewen; Naredla, Rajasekhar; Hoye, Thomas; Macosko, Christopher

    Branched PLA was prepared by melt blending with tri-functional aziridine (T-Az) and pyromellitic dianhydride (PMDA). 1HNMR, gel permeation chromatography (GPC) and rheology were used to characterize the topological structures of branched PLA. Fast reaction between PLA carboxyl end group and T-Az resulted in 3-arm stars and increased the molecular weight. However, the 3-arm stars did not show strain hardening behavior under extensional flow. After modifying PLA hydroxyl end group with PMDA, PLA can react with T-Az on both chain ends and form long chain branched structure, which showed strain hardening in extension. It was found that that only 10% of the PLA hydroxyl end groups reacted with PMDA. This work is supported by Center for Sustainable Polymers.

  2. Synthesis and Characterization of Organic Impurities in Bortezomib Anhydride Produced by a Convergent Technology

    Science.gov (United States)

    Ivanov, Andrey S.; Shishkov, Sergey V.; Zhalnina, Anna A.

    2012-01-01

    A profile of impurities in bortezomib anhydride, produced by a recently developed convergent technology, has been characterized. HPLC-MS analysis of the drug essence revealed three impurities: an epimer of bortezomib, resulting from partial racemization of l-phenylalanine’s stereogenic center during the chemical synthesis, and two epimeric products of oxidative degradation of bortezomib, in which boron is replaced by the OH group. The impurities were obtained by chemical synthesis and characterized by physical methods. PMID:22396904

  3. Dodecenylsuccinic Anhydride Derivatives of Gum Karaya (Sterculia urens): Preparation, Characterization, and Their Antibacterial Properties

    OpenAIRE

    Padil, V.V.T.; Senan, Chandra; Cernik, M

    2015-01-01

    Esterifications of the tree-based gum, gum karaya (GK), using dodecenylsuccinic anhydride (DDSA) were carried out in aqueous solutions. GK was deacetylated using alkali treatment to obtain deacetylated gum karaya (DGK). The DGK and its DDSA derivative were characterized using gel permeation chromatography/multiangle laser light scattering (GPC/MALLS), attenuated total reflectance–Fourier transform infrared spectroscopy (ATR-FTIR), scanning electron microscopy (SEM), proton nuclear magnetic re...

  4. Perylene anhydride fused porphyrins as near-infrared sensitizers for dye-sensitized solar cells

    KAUST Repository

    Jiao, Chongjun

    2011-07-15

    Two perylene anhydride fused porphyrins 1 and 2 have been synthesized and employed successfully in dye-sensitized solar cells (DSCs). Both compounds showed broad incident monochromatic photon-to-current conversion efficiency spectra covering the entire visible spectral region and even extending into the near-infrared (NIR) region up to 1000 nm, which is impressive for ruthenium-free dyes in DSCs. © 2011 American Chemical Society.

  5. Effect of Textured Surfactant Brushes on Polymer-Layered Silicate Nanocomposite Morphology

    Science.gov (United States)

    2004-02-01

    melt processing a mixture of stearylammonium-exchanged montmorillonite, maleic anhydride -modified polypropylene oligomer, and homopolypropylene (29–31...molecular weights was performed using both the XMASS (Bruker) and Polymerix (Sierra Analytics) software packages. Surfactant nomenclature and...properties are recorded in table 1. The nomenclature used is such that for any surfactant it provides information about its approximate molecular weight

  6. Techno-economic analysis of unsaturated polyester production from waste PET

    OpenAIRE

    Drah, Abdusalam; Rusmirović, Jelena D.; Milošević, Milena; Kalifa, Mustafa; Stojiljković, Ivana; Rančić, Milica; Aleksandar D. Marinković

    2016-01-01

    Unsaturated polyester resins (UPe) were synthesized from maleic anhydride and products of glycolysis, obtained by polyethylene terephthalate (PET) depolymerization with dipropylene glycol (DPG) in the presence of tetrabutyl titanate catalyst. Waste PET glycolyzed product and UPes were characterized by FTIR and NMR spectroscopy, elemental analysis, acid value (AV), hydroxyl value (HV) and iodine value. Nanocomposites, based on unsaturated polyester resins and hexamethyldisilazane modified sili...

  7. Reinforcement of polypropylene by annual plant fibers: optimisation of the coupling agent efficiency

    NARCIS (Netherlands)

    Snijder, M.H.B.; Bos, H.L.

    2000-01-01

    Annual growth agrofibers like flax and jute can compete with glass fibers, considering their intrinsic mechanical properties. This paper discusses reinforcement of polypropylene (PP) homopolymer with flax bast fibers. Maleic Anhydride modified PP (MAPP) grades are screened on coupling efficiency. Th

  8. Effect of Multiple Extrusions on the Impact Properties of Polypropylene/Clay Nanocomposites

    DEFF Research Database (Denmark)

    Klitkou, Rasmus; Jensen, Erik Appel; Christiansen, Jesper de Claville

    2012-01-01

    Polypropylene (PP)-based polymer nanocomposites containing organically modified montmorillonite (OMMT) with and without maleic anhydride grafted PP, were compounded by twin-screw extrusion. The extrusion process was repeated various numbers of times to increase the extruder residence time (TR) and...

  9. Preparation and controlled release effect of soybean protein/multicarboxylic acids modified cotton fabric%大豆蛋白/复合羧酸改性棉织物的制备及其缓释效果

    Institute of Scientific and Technical Information of China (English)

    许云辉; 王晓明; 张晓丽

    2013-01-01

    To develop an eco-friendly and multifunctional cotton fabric,the modification treatment of cotton fabric was undertaken using citric acid,maleic acid and soybean protein so that the chemical bonding between soybean protein and cotton fabric was formed through the bridging function of multicarboxylic acids.Effects of treating conditions on the weighting percentage of cotton fabric were analyzed and the optimized process parameters were obtained.The characterization of infrared spectra and X-ray photoelectron spectrometry showed that the esterification crosslinking occurred between multicarboxylic acids and macromolecules of cotton fiber according to ring-anhydride mechanism,while the soybean protein was adhered to the cotton fabric with amido bond by the bridging function of multicarboxylic acids.The breaking strength of soybean protein modified cotton fabric slightly decreased,whereas the anti-ultraviolet-ray property of the modified cotton fabric after cactus extract treatment improved remarkably.Furthermore,the drug controlled release test showed that when soybean protein modified cotton fabric was used as the carrier for cactus extract,good controlled release effect was achieved.%为开发生态多功能棉织物,采用柠檬酸、马来酸、大豆蛋白对棉织物进行改性处理,通过复合羧酸的桥联作用,使大豆蛋白与棉织物形成化学键交联结合,研究处理条件对棉织物增重率的影响,并得出最优工艺参数.红外光谱和光电子能谱测试表明,复合羧酸与棉纤维大分子按环酐机制产生酯化交联,大豆蛋白借助复合羧酸的桥联作用以酰胺键共价结合在棉织物上.大豆蛋白改性棉织物的断裂强力略有下降,再经仙人掌提取物处理的大豆蛋白改性棉织物抗紫外线性能明显提高,药物缓释试验显示,大豆蛋白改性棉织物作为药物载体对仙人掌提取物的缓释效果良好.

  10. Anticlastogenic effect of Spirulina maxima extract on the micronuclei induced by maleic hydrazide in Tradescantia.

    Science.gov (United States)

    Ruiz Flores, L Elvia; Madrigal-Bujaidar, Eduardo; Salazar, María; Chamorro, Germán

    2003-02-07

    The aim of this investigation was to determine if extracts of Spirulina maxima reduce the genotoxic damage induced by maleic hydrazide (MH) using the Tradescantia biosssay. Two types of extracts from the alga were prepared: an aqueous extract with two different concentrations, 100 and 500 mg/ml, and a second one, the extract of a 1% solution of dimethyl sulfoxide (DMSO) which corresponded to 100 mg/ml of the alga. The capacity of MH to induce micronuclei (MN) was initially established by administering 0.005, 0.01, and 0.015 mg/ml of the chemical to the Tradescantia inflorescences, and observing its effect after 24 h.The results of this experiment showed a significant MN increase with the two high concentrations tested, although no dose-response effect was observed. For the anticlastogenic assay, the extracts of Spirulina were applied to the inflorescences alone or immediately before the application of MH (0.01 mg/ml) and the induced MN were observed 24 h later. We found that none of the extracts increased the MN level with respect to the untreated plants; also, that MH more or less doubled the basal micronuclei frequency, and finally, that all tested extracts reduced the genotoxic damage caused by MH. The inhibitory indices obtained for the aqueous extracts (100 and 500 mg/ml) and for the DMSO extract were respectively 59, 85, and 56.3%. These data indicate that Spirulina is an anticlastogenic agent and suggest that it is advisable to extend studies on this matter using other biological models.

  11. Maleic Acid--but Not Structurally Related Methylmalonic Acid--Interrupts Energy Metabolism by Impaired Calcium Homeostasis.

    Directory of Open Access Journals (Sweden)

    Ali Tunç Tuncel

    Full Text Available Maleic acid (MA has been shown to induce Fanconi syndrome via disturbance of renal energy homeostasis, though the underlying pathomechanism is still under debate. Our study aimed to examine the pathomechanism underlying maleic acid-induced nephrotoxicity. Methylmalonic acid (MMA is structurally similar to MA and accumulates in patients affected with methymalonic aciduria, a defect in the degradation of branched-chain amino acids, odd-chain fatty acids and cholesterol, which is associated with the development of tubulointerstitial nephritis resulting in chronic renal failure. We therefore used MMA application as a control experiment in our study and stressed hPTECs with MA and MMA to further validate the specificity of our findings. MMA did not show any toxic effects on proximal tubule cells, whereas maleic acid induced concentration-dependent and time-dependent cell death shown by increased lactate dehydrogenase release as well as ethidium homodimer and calcein acetoxymethyl ester staining. The toxic effect of MA was blocked by administration of single amino acids, in particular L-alanine and L-glutamate. MA application further resulted in severe impairment of cellular energy homeostasis on the level of glycolysis, respiratory chain, and citric acid cycle resulting in ATP depletion. As underlying mechanism we could identify disturbance of calcium homeostasis. MA toxicity was critically dependent on calcium levels in culture medium and blocked by the extra- and intracellular calcium chelators EGTA and BAPTA-AM respectively. Moreover, MA-induced cell death was associated with activation of calcium-dependent calpain proteases. In summary, our study shows a comprehensive pathomechanistic concept for MA-induced dysfunction and damage of human proximal tubule cells.

  12. THE THERMAL AND ABLATIVE DEGRADATION OF SOME EPOXY RESINS CURED WITH METHYL BICYCLO(2.2.1)HEPTENE-2,3-DICARBOXYLIC ANHYDRIDE (NMA).

    Science.gov (United States)

    ABLATION), (* EPOXY RESINS , (*PYROLYSIS, EPOXY RESINS ), CYCLOALKENES, ANHYDRIDES, CATALYSTS, ADDITIVES, CROSSLINKING(CHEMISTRY), REACTION KINETICS, DEGRADATION, AGING(MATERIALS), INFRARED SPECTRA, CHROMATOGRAPHIC ANALYSIS.

  13. Importance of relative humidity in the oxidative ageing of organic aerosols: case study of the ozonolysis of maleic acid aerosol

    Directory of Open Access Journals (Sweden)

    P. J. Gallimore

    2011-12-01

    Full Text Available Many important atmospheric aerosol processes depend on the chemical composition of the aerosol, e.g. water uptake and particle cloud interactions. Atmospheric ageing processes, such as oxidation reactions, significantly and continuously change the chemical composition of aerosol particles throughout their lifetime. These ageing processes are often poorly understood. In this study we utilize an aerosol flow tube set up and an ultra-high resolution mass spectrometer to explore the effect of relative humidity (RH in the range of <5–90% on the ozonolysis of maleic acid aerosol which is employed as model organic aerosol system. Due to the slow reaction kinetics relatively high ozone concentrations of 160–200 ppm were used to achieve an appreciable degree of oxidation of maleic acid. The effect of oxidative ageing on the hygroscopicity of maleic acid particles is also investigated using an electrodynamic balance and thermodynamic modelling. RH has a profound effect on the oxidation of maleic acid particles. Very little oxidation is observed at RH < 50% and the only observed reaction products are glyoxylic acid and formic acid. In comparison, when RH > 50% there are about 15 oxidation products identified. This increased oxidation was observed even when the particles were exposed to high humidities long after a low RH ozonolysis reaction. This result might have negative implications for the use of water as an extraction solvent for the analysis of oxidized organic aerosols. These humidity-dependent differences in the composition of the ozonolyzed aerosol demonstrate that water is both a key reactant in the oxidation scheme and a determinant of particle phase and hence diffusivity. The measured chemical composition of the processed aerosol is used to model the hygroscopic growth, which compares favourably with water uptake results from the electrodynamic balance measurements. A reaction mechanism is presented which takes into account the RH dependent

  14. Enzyme-catalyzed Synthesis of Vitamin E Succinate Using a Chemically Modified Novozym-435%化学修饰Novozym-435酶催化合成维生素E琥珀酸酯的研究

    Institute of Scientific and Technical Information of China (English)

    尹春华; 张聪; 高明

    2011-01-01

    Vitamin E succinate was synthesized in organic solvents using a modified Novozym-435 as catalyst. In order to improve the catalytic performance of Novozym-435, the enzyme was modified using acetic anhydride, propionic anhydride and succinic anhydride separately. We found that both the hydrolytic activity and the thermal stability of the modified Novozym-435 were enhanced compared with the unmodified enzyme. The modified Novozym-435 catalysts were used to synthesize the succinate derivative of vitamin E. Compared with the native Novozym-435, the catalytic activity of the modified novozym-435 in promoting the synthesis of vitamin E succinate was dramatically increased, with the novozym-435 modified with succinic anhydride (N435-S) as the most active catalyst. Conditions for the synthesis of vitamin E succinate were also optimized. A mixture of tert-butanol and DMSO (volume ratio of 2: 3) was the most suitable medium for the reaction, whereas the appropriate molar ratio of vitamin E to succinic anhydride and reaction temperature were 1: 5 and 40 ℃, respectively. Under these reaction conditions, the yield of vitamin E succinate reached 94.4%. N435-S could be reused for five batches.

  15. Optimisation of octinyl succinic anhydride starch stablised w1/o/w2 emulsions for oral destablisation of encapsulated salt and enhanced saltiness.

    Science.gov (United States)

    Chiu, Natalie; Tarrega, Amparo; Parmenter, Christopher; Hewson, Louise; Wolf, Bettina; Fisk, Ian D

    2017-08-01

    Sodium (salt) was encapsulated within the inner water phase of w1/o/w2 food emulsions externally stabilised by starch particles with the ultimate aim of enhancing saltiness perception. The physical properties of the starch particles were modified by octenyl succinic anhydride (OSA) treatment (0-3%) to vary the degree of hydrophobicity of the emulsifying starch. During oral processing native salivary amylase hydrolysed the starch and destabilised the o/w emulsion releasing the inner w/o phase and subsequently sodium into the oral cavity, resulting in a salty taste. Whilst increasing OSA treatment levels increased the stability of the emulsion, intermediate or low levels of starch modification resulted in enhanced saltiness. It is therefore proposed that 1.5% OSA modified starch is optimal for sodium delivery and 2% OSA modified starch is optimal for sodium delivery in systems that require greater process stability. It is also shown that sodium release was further enhanced by oral processing and was positively correlated with native amylase activity. The results demonstrate a promising new approach for the reduction of salt or sugar in emulsion based foods.

  16. 界面改性剂对PE基木塑复合材料性能的影响%Effects of Interfacial Modifiers on Properties of PE Based Wood Plastic Composites

    Institute of Scientific and Technical Information of China (English)

    张克宏; 肖慧

    2012-01-01

    以高密度聚乙烯(HDPE)和木粉为主要原料、马来酸酐接枝聚乙烯(MAPE)和硅烷偶联剂(KH570)为界面改性剂,采用压制成型法制备了PE基木塑复合材料.研究了界面改性剂MAPE和KH570用量对复合材料力学性能的影响,并采用FT-IR和SEM对复合材料的微观结构进行了表征.结果表明:界面改性剂MAPE和KH570可以显著改善木塑复合材料的拉伸强度、冲击强度和弯曲强度,当木粉、HDPE、MAPE、KH570质量比为40∶36∶24∶5时,木塑复合材料的综合力学性能最佳;FT-IR和SEM表明:在界面改性剂MAPE和KH570的作用下,木粉在塑料基体中的分散均匀,相容性提高,并发生了一定程度的化学键合.%The PE based wood-plastic composites(WPC)were prepared via compression molding using high density polyethylene(HDPE) and wood powder as the main raw material,maleic anhydride grafted polyethylene (MAPE) and silane coupling agent(KH-570) as interfacial modifiers.The effects of the content of interfacial modifiers MAPE and KH-570 on the mechanical properties of WPC were investigated.The microstructure of the composites was characterized by means of SEM and FT-IR.The results showed that the MAPE and KH-570 can significantly improve the tensile strength,the impact strength and the flexural strength of WPC.When the mass ratio of wood powder,HDPE,MAPE and KH-570 was 40:36=24:5,WPC had excellent comprehensive mechanical properties.Based on the analysis of FT-IR and SEM,the phenomenon that wood powder dispersed homogeneously in the PE matrix was observed.There were certain extent chemistry linkages between the constituents of WPC.

  17. Quantification of free sphingosine in cultured cells by acylation with radioactive acetic anhydride.

    Science.gov (United States)

    Ohta, H; Ruan, F; Hakomori, S; Igarashi, Y

    1994-11-01

    A simple and sensitive method for quantification of sphingosine in cellular lipid extracts was developed. The assay is based on quantitative conversion of sphingosine to N-[3H]acetylated sphingosine ([3H]C2-ceramide) by N-acylation with [3H]acetic anhydride under certain conditions. Sphingosine was extracted from cultured cells with chloroform and methanol and then treated with base to remove interfering glycerolipids having reactive amino groups (e.g., phosphatidylethanolamine or phosphatidylserine). Sphingosine was acylated with [3H]acetic anhydride in the presence of 0.004 N NaOH. Acylation was complete in 1 h at 37 degrees C when sphingosine was present in the picomole range. After the acylation, samples were treated with NaOH to reduce background radioactivity by removing the remaining [3H]acetic anhydride and hydrolyzing any ester linkages formed during the acylation and resolved by thin-layer chromatography. [3H]C2-ceramide converted from sphingosine with the acylation was detected with radioautography and quantitated by scraping the corresponding band and counting its radioactivity with a scintillation counter. [3H]C2-ceramide formed was quantitatively measured. This assay allows quantification of sphingosine over a range of 10 to 1500 pmol. The amount of sphingosine in lipid extracts from cultured cells was proportional to the number of cells. Sphingosine levels in human gastric cancer KATO III cells, human promyelocytic leukemic HL60 cells, and human monoblastic U937 cells, determined by this method, were 26.6 +/- 2.2, 6.3 +/- 0.4, and 6.8 +/- 0.6 pmol per 10(6) cells, respectively. Our new procedure allows quantification of sphingosine levels present in the low picomole range in lipid extracts from biological samples.

  18. Co(Ⅲ)-Modified SBA-15: Preparation, Characterization and Catalytic Performance for Epoxidation of Cyclohexene%Co(Ⅲ)官能化SBA-15的制备、表征及其催化环己烯环氧化

    Institute of Scientific and Technical Information of China (English)

    高鹏飞; 张铁明; 周媛; 赵永祥

    2011-01-01

    通过环戊二烯基修饰的SBA-15(SBA-15-Cp)与马来酸酐的Diels-Alder反应及水解合成了邻二羧酸官能化的SBA-15,并将原位生成的Co(Ⅲ)络合物负载于其上制得Co(Ⅲ)官能化SBA-15样品SBA-15-Co(Ⅲ).傅里叶变换红外光谱、元素分析和X射线光电子能谱法结果证实羧酸官能团和Co(Ⅲ)成功地引入到介孔材料中.X射线粉末衍射、N2物理吸附-脱附和高分辨透射电镜等表征结果表明,在制备过程中,材料仍较好地保持SBA-15的孔结构.以异丁醛为牺牲剂,乙腈为溶剂,氧气流速5 ml/min,在40℃反应6 h时,SBA-15-Co(Ⅲ)在环己烯环氧化反应中表现出较高的活性和稳定性,环氧环己烷产率和选择性分别达58%和63.7%,且经过6次循环后,仍分别可达51.6%和56.5%.%A Co(Ⅲ)-modified mesoporous material (SBA-15-Co(Ⅲ)) was prepared by supporting an in situ formed Co(Ⅲ) complex on o-dicarboxylic acid modified SBA-I5 (SBA-15-(COOH)2) that was synthesized by first the Diels-Alder reaction between maleic anhydride and cyclopentadienyl-modified SBA-15 (SBA-15-Cp) and then the hydrolysis of resulting anhydride. Fourier transform infrared spectroscopy, elemental analysis (ICP-AES), and X-ray photoelectron spectroscopy confirmed the successful incorporation of carboxyl and Co(Ⅲ) in the mesopores. The results of X-ray powder diffraction, N2-sorption, and high resolution transmission electron microscopy showed that SBA-I5-Co(Ⅲ) well maintained the mesostructure of SBA-15. In the presence of isobutyraldehyde, SBA-I5-Co(Ⅲ) showed moderate activity and stability in the epoxidation of cyclohexene when the flow rate of O2 was 5 ml/min. the solvent was acetonitrile. the reaction temperature was 40 ℃, and time was 6 h. The yield and selectivity of cyclohexene oxide could reach 58% and 63.7%, respectively. The yield and selectivity of cyclohexene oxide could still maintained 5 1.6% and 56.5% after six catalytic cycles.

  19. Perfluoroalkylation of Unactivated Alkenes with Acid Anhydrides as the Perfluoroalkyl Source.

    Science.gov (United States)

    Kawamura, Shintaro; Sodeoka, Mikiko

    2016-07-18

    An efficient perfluoroalkylation of unactivated alkenes with perfluoro acid anhydrides was developed. Copper salts play a crucial role as a catalyst to achieve allylic perfluoroalkylation with the in situ generated bis(perfluoroacyl) peroxides. Furthermore, carboperfluoroalkylation of alkene bearing an aromatic ring at an appropriate position on the carbon side chain was found to proceed under metal-free conditions to afford carbocycles or heterocycles bearing a perfluoroalkyl group. This method, which makes use of readily available perfluoroalkyl sources, offers a convenient and powerful tool for introducing a perfluoroalkyl group onto an sp(3) carbon to construct synthetically useful skeletons.

  20. Crystal structure of γ-ethyl-l-glutamate N-carb-oxy anhydride.

    Science.gov (United States)

    Kanazawa, Hitoshi; Inada, Aya

    2015-01-01

    In the title compound (alternative name N-carboxy-l-glutamic anhydride γ-ethyl ester), C8H11NO5, the oxazolidine ring is essentially planar, with a maximum deviation of 0.019 (2) Å. In the crystal, mol-ecules are linked by N-H⋯O hydrogen bonds between the imino group and the carbonyl O atom in the ethyl ester group, forming a tape structure along the c-axis direction. The oxazolidine rings of adjacent tapes are arranged into a layer parallel to the ac plane. This arrangement is favourable for the polymerization of the title compound in the solid state.

  1. Screening and assignment of phenylboronic acid and its anhydride formation by NMR spectroscopy

    Science.gov (United States)

    Chaudhari, Sachin R.

    2015-08-01

    The study discusses an approach that allows simultaneous determination of boronic acid and its anhydride without the need for tedious physical separation of the mixture. The assignment of the proton spectra of monomer, dimer and trimer was achieved by combining utility of 1D and 2D experimental techniques including 2D DOSY. The differential intensities of NMR peaks and supplementary resonances were detected in low polar solvents, such as, chloroform, toluene and in a non-polar solvent benzene. A fascinating phenomenon is observed at lower temperature where there is a formation of aryl boronic acid with the disappearance of boraxine formation.

  2. POLYMER—SUPPORTED RHODIUM CATALYSTS FOR CARBONYLATION OF METHYL ACETATE TO ACETIC ANHYDRIDE

    Institute of Scientific and Technical Information of China (English)

    CHENDean; HUANGShizhuan; 等

    1993-01-01

    Two kinds of rhodium catalysts supported on cross-linked styrene-divinylbenzene copolymers containing bipyridine or o-phenylene diamine have been prepared and found to display high activity for methyl acetate carbonylation to form acetic anhydride,the activities are even higher than their homogeneous counterparts. XPS analysis was used to characterize the synthetic catalysts.The apparent activation parameters were determined to be Eα=73.3KJ/mol,ΔH≠=66.3KJ/mol,ΔS≠=-28.6eu.These parameters are very close to those in methanol carbonylation and imply to have analogous mechanism in both cases.

  3. Styromal based polymer films modified with copper microparticles

    Directory of Open Access Journals (Sweden)

    Viktor F. Vargalyuk

    2016-12-01

    Full Text Available A method for the synthesis of polymeric film based on a copolymer of styrene and maleic anhydride (stiromal and oligodiol was suggested. Block copolymer of ethylene glycol and propylene glycol was used as oligodiol. It was shown that synthesized materials have moderate water swelling capacity in and ion-exchange properties. Static exchange capacity in 0.1 mol/L NaOH aqueous solution is within the interval of 1.44–1.76 mmol/g. At air-dry state films have a tensile strength of 4–6.6 MPa and an elongation at break tensile 38–61 %. The effect of stiromal molecular weight and oligodiol type, and conditions of film formation on ion-exchange and physical-mechanical properties of the films was studied. The synthesized material appeared to be able to sorb Cu2+-ions from neutral and acidic solutions. The distribution coefficient in case of sorption from slightly acidic solution with Cu2+ concentration of 50 mg/L was 48–50. Composite material with a metal submicroparticles uniformly distributed in the polymeric matrix was obtained by chemical reduction of copper ions sorbed. It was found that the film acquires electric conductivity, as a result of filling of metal particles, which allows copper electrodeposition on the film surface.

  4. Preparation and characterization of poly(maleic acid)-grafted cross-linked chitosan microspheres for Cd(II) adsorption.

    Science.gov (United States)

    Yu, Zhenzhen; Dang, Qifeng; Liu, Chengsheng; Cha, Dongsu; Zhang, Haifeng; Zhu, Wenjing; Zhang, Qianqian; Fan, Bing

    2017-09-15

    A novel adsorbent, composed of poly(maleic acid)-grafted cross-linked chitosan microspheres (PMACCMs), was prepared via cross-linking with glutaraldehyde and modification by grafting maleic acid. FTIR, zeta potential, elemental analysis, (13)C NMR, DTG, laser particle size analysis, SEM, and BET methods were applied to characterize PMACCMs, exhibiting a successful fabrication, good thermostability, and well-defined surface microstructure beneficial to Cd(II) adsorption. The effects of pH, contact time, and initial concentration on Cd(II) adsorption were also investigated, and the maximum adsorption capacity was 39.2mgg(-1), indicating a great improvement as compared with that (14.5mgg(-1)) of cross-linked chitosan microspheres. The experimental data were well fitted with pseudo-second-order kinetic and Langmuir isotherm models. Five-cycle reusability tests demonstrated PMACCMs could be repeatedly used with a small adsorption capacity loss (<15%). Additionally, the adsorption mechanism was proposed. All the results confirmed that PMACCMs, which presented outstanding adsorption capability and reusability, could be a good candidate for wastewater purification. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Chromium(III, VI) speciation analysis with preconcentration on a maleic acid-functionalized XAD sorbent

    Energy Technology Data Exchange (ETDEWEB)

    Yalcin, Sibel; Apak, Resat

    2004-03-03

    Chromium may exist in environmental waters as Cr(III) and Cr(IV), the latter being the toxic and carcinogenic form. Since atomic absorption spectrometry (AAS) and inductively coupled plasma atomic emission spectrometry can only yield information on total Cr concentration, a polymer resin bearing O,O-donor chelating groups such as the maleic acid-functionalized XAD-(CO)CH-CH-COOH resin was synthesized to selectively retain Cr(III) at pH 4.0-5.5. The dynamic breakthrough capacity of the resin for Cr(III) at pH 5.0 was 7.52 mg g{sup -1}, and the preconcentration factor extended to 250-300. Chromium(III) in the presence of 250-fold Cr(VI)--which was not retained--could be effectively preconcentrated on the NH{sub 4}{sup +}-form of the resin and determined by AAS or diphenylcarbazide (DPC) spectrophotometry. When Cr(VI) was reduced to Cr(III) with Na{sub 2}SO{sub 3} solution brought to pH 1 by the addition of 1 M H{sub 2}SO{sub 4}, and preconcentrated on the resin, total Cr could be determined. The developed method was validated with a blended coal sample CRM-1632. Since the adsorption behavior as a function of pH of possible interferent metal ions, e.g. Ni(II), Co(II), Cu(II), Cd(II), Zn(II), Pb(II) and Fe(III), was similar to that of Cr(III), selective elution of Cr(III) from the resin was realized using a mixture of 1 wt.% H{sub 2}O{sub 2}+1 M NH{sub 3}. The eluate containing Cr as chromate could be directly analyzed by diphenyl carbazide spectrophotometry without any adverse effect from the common interferents of this method, i.e. Fe(III), Cu(II) Hg(II), VO{sub 3}{sup -}, MoO{sub 4}{sup 2-} and WO{sub 4}{sup 2-}. Various synthetic waste solutions typical of electroplating bath effluents containing Cr, Cu, Ni, Zn, Na, Ca, cyanide (and chemical oxidation demand (COD), achieved by glucose addition) were subjected to pretreatment procedures such as hypochlorite oxidation (of cyanide) and catalytic oxidation (of COD) with peroxodisulfate. Chromium determination gave

  6. Soluble Synthetic Analogs of Malaria Pigment: Structure of Mesohematin Anhydride [FeIII(MP-IX)]2 and Solution Interaction with Chloroquine

    Energy Technology Data Exchange (ETDEWEB)

    D Bohle; E Dodd; A Kosar; L Sharma; P Stephens; L Suarez; D Tazoo

    2011-12-31

    Changing the vinyl groups of hematin anhydride to either ethyl or hydrogen groups results in increased solubility (Por=porphyrin). Determination of the weak binding constants of the antimalarial drug chloroquine to dimers of these hematin anhydride analogues suggests that solution-phase heme/drug interactions alone are unlikely to be the origin of the action of the drug.

  7. One-pot odourless synthesis of thioesters via in situ generation of thiobenzoic acids using benzoic anhydrides and thiourea

    Directory of Open Access Journals (Sweden)

    Mohammad Abbasi

    2015-07-01

    Full Text Available An efficient and odourless procedure for a one-pot synthesis of thioesters by the reaction of benzoic anhydrides, thiourea and various organic halides (primary, allylic, and benzylic or structurally diverse, electron-deficient alkenes (ketones, esters, and nitriles in the presence of Et3N has been developed. In this method, thiobenzoic acids were in situ generated from the reaction of thiourea with benzoic anhydrides, which were subjected to conjugate addition with electron-deficient alkenes or a nucleophilic displacement reaction with alkyl halides.

  8. 1-Butyl-3-methylimidazolium Salts as New Catalysts to Produce Epoxy-anhydride Polymers with Improved Properties

    Directory of Open Access Journals (Sweden)

    Mikhail S. Fedoseev

    2014-01-01

    Full Text Available We report the curing process of epoxy oligomers by using isomethyltetrahydrophthalic anhydride catalyzed with 1-butyl-3-methylimidazolium salts. Catalytic action has been ascertained to be dependent on the nature of anion. Salts with (Br- and (PO4- anions appeared to be most active. Formation of salt adducts with epoxy resin and anhydride is shown. Polymers having higher values of strength and glass transition temperature—as compared with similar epoxy systems cured in the presence of tertiary amines as catalysts—are prepared.

  9. Efficient photochemical generation of peroxycarboxylic nitric anhydrides with ultraviolet light emitting diodes

    Directory of Open Access Journals (Sweden)

    N. D. Rider

    2015-01-01

    Full Text Available Photochemical sources of peroxycarboxylic nitric anhydrides (PANs are utilized in many atmospheric measurement techniques for calibration or to deliver an internal standard. Conventionally, such sources rely on phosphor-coated low-pressure mercury (Hg lamps to generate the UV light necessary to photo-dissociate a dialkyl ketone (usually acetone in the presence of a calibrated amount of nitric oxide (NO and oxygen (O2. In this manuscript, a photochemical PAN source in which the Hg lamp has been replaced by arrays of ultraviolet light-emitting diodes (UV-LEDs is described. The output of the UV-LED source was analyzed by gas chromatography (PAN-GC and thermal dissociation cavity ring-down spectroscopy (TD-CRDS. Using acetone, diethyl ketone (DIEK, diisopropyl ketone (DIPK, or di-n-propyl ketone (DNPK, respectively, the source produces peroxyacetic (PAN, peroxypropionic (PPN, peroxyisobutanoic (PiBN, or peroxy-n-butanoic nitric anhydride (PnBN from NO in high yield (> 90%. Box model simulations with a subset of the Master Chemical Mechanism (MCM were carried out to rationalize products yields and to identify side products. The use of UV-LED arrays offers many advantages over conventional Hg lamp setups, including greater light output over a narrower wavelength range, lower power consumption, and minimal generation of heat.

  10. Gelatin-based biomaterial engineering with anhydride-containing oligomeric cross-linkers.

    Science.gov (United States)

    Loth, Tina; Hötzel, Rudi; Kascholke, Christian; Anderegg, Ulf; Schulz-Siegmund, Michaela; Hacker, Michael C

    2014-06-01

    Chemically cross-linked gelatin hydrogels are versatile cell-adhesive hydrogel materials that have been established for a variety of biomedical applications. The most prominent cross-linker is glutaraldehyde, which, however, has been described to cause compatibility problems and loss of microscopic but relevant structural features. A recently developed oligomeric cross-linker that contains anhydride functionalities was evaluated as cross-linker for the fabrication of gelatin-based hydrogels and microparticles. In a fast curing reaction, hydrogels composed of gelatin and oligomeric cross-linker were fabricated with good conversion over a wide concentration range of constituents and with cross-linkers of different anhydride contents. Hydrogel properties, such as dry weight and mechanics, could be controlled by hydrogel composition and rheological properties correlated to elastic moduli from 1 to 10 kPa. The gels were shown to be cytocompatible and promoted cell adhesion. In soft formulations, cells migrated into the hydrogel bulk. Gelatin microparticles prepared by a standard water-in-oil emulsion technique were also treated with the novel oligomers, and cross-linking degrees matching those obtained with glutaraldehyde were obtained. At the same time, fewer interparticular cross-links were observed. Fluorescein-derivatized cross-linkers yielded labeled microparticles in a concentration-dependent manner. The oligomeric cross-linkers are presented as an efficient and possibly more functional and compatible alternative to glutaraldehyde. The engineered hydrogel materials hold potential for various biomedical applications.

  11. Lysine adducts between methyltetrahydrophthalic anhydride and collagen in guinea pig lung.

    Science.gov (United States)

    Jönsson, B A; Wishnok, J S; Skipper, P L; Stillwell, W G; Tannenbaum, S R

    1995-11-01

    The formation of adducts between methyltetrahydrophthalic anhydride (MTHPA), an important industrial chemical and potent allergen, and collagen from guinea pig lung tissue was investigated. Collagen peptides were obtained from the lung tissue by homogenization, defatting, washing, and digestion with collagenase. In experiments in vitro, lung tissue was exposed to 8.4 mumol (50 microCi) of 14C MTHPA. The amount of adducts was 97 nmol MTHPA/g of wet tissue as determined from the bound radioactivity. In a study in vivo, four guinea pigs were injected intratracheally with 8.4 mumol of 14C MTHPA each. The amount of adducts was 0-1.2 nmol MTHPA/g of wet tissue (determined by bound radioactivity). N epsilon-methyltetrahydrophthaloyl-L-lysine (MTHPL) was synthesized and characterized by NMR, UV, and mass spectrometry (MS). A method to analyze MTHPL, after derivatization with methanol and pentafluorobenzoyl chloride, using gas chromatography-MS was developed. Analysis of Pronase-digested MTHPA-exposed lung tissue showed a concentration of 19 nmol MTHPL/g wet lung in vitro and between 0 and 0.15 nmol MTHPL/g wet lung in vivo. Thus, 20% in vitro and 12-15% in vivo of the bound radioactivity was found as adducts with lysine. These results are a first step toward studies of allergenic epitopes in proteins and methods for biological monitoring of exposure to acid anhydrides.

  12. Polycondensation of Tetrahydrofuran with Phthalic Anhydride Induced By a Proton Exchanged Montmorillonite Clay

    Directory of Open Access Journals (Sweden)

    Mohammed Belbachir

    2003-05-01

    Full Text Available Abstract: “Maghnite” a montmorillonite sheet silicate clay, exchanged with protons to produce “H-Maghnite” is an efficient catalyst for polymerization of many vinylic and heterocyclic monomers (Belbachir, M. U.S. Patent. 066969.0101 –2001. The structure compositions of both “Maghnite” and “H-Maghnite” have been developed. This catalyst was used for the polycondensation of the tetrahydrofuran with phthalic anhydride. The polymerization was performed under suitable conditions at temperature (40°C, in presence of acetic anhydride. Experiments revealed that polymerization induced by “H-Maghnite”, proceed in bulk and the conversion increases with increasing “H-Maghnite” proportion.

  13. Catalytic behavior of Sn/Bi metal powder in anhydride-based epoxy curing.

    Science.gov (United States)

    Jang, Keon-Soo; Eom, Yong-Sung; Moon, Jong-Tae; Oh, Yong-Soo; Nam, Jae-Do

    2009-12-01

    In this paper, we report the catalytic activity of the Sn/Bi alloy beads and its acceleration of the exothermic epoxy curing reactions in various thermal conditions and bead compositions. As being used as low-melting solder balls in electronic interconnection processes with various epoxy systems, it was found that the Sn/Bi beads substantially lowered the exothermic peak temperature of the diglycidyl ether of bisphenol A (DGEBA)/anhydride systems in up to ca. 140 degrees C depending on different types of anhydride curing agents. The catalytic activation of Sn/Bi powder was initiated with a small amount of Sn/Bi powder, for example, lowering ca. 50 degrees C of the exothermic peak temperature by adding only 0.1 vol% of Sn/Bi powder. The catalytic capability of the powder was increased by using smaller sized beads corresponding to larger catalytic surface area at the same volume fraction. Exhibiting a latent catalytic effect, the catalytic activity of Sn/Bi powder was remained latent at temperatures lower than 100 degrees C in isothermal conditions.

  14. Investigação da cinética de cura por calorimetria diferencial exploratória (DSC de resinas epóxi preparadas a partir de óleo de soja epoxidado com diferentes anidridos e aminas terciárias Investigation of the kinetics of cure by differential scanning calorimetry (DSC of epoxy resins prepared from epoxidized soybean oil with different anhydrides and tertiary amines

    Directory of Open Access Journals (Sweden)

    Ana P. O. Costa

    2011-01-01

    Full Text Available No presente trabalho, utilizou-se a calorimetria diferencial exploratória (DSC para investigar a cinética da reação de cura de resinas epóxi produzidas a partir da reação do óleo de soja epoxidado (ESO, com os anidridos dodecenilsuccínico (DDS, maleico (MAL, ftálico (FTA, succínico (SUC e hexahidroftálico (CH, atuando como agentes de cura, e na presença de aminas terciárias como a trietilamina (TEA, a N,N'-dimetilanilina (ARO e a 1,4- diazobiciclo [2,2,2] octano (DABCO, atuando como catalisadores. A taxa de aquecimento, a natureza química e a estrutura do anidrido e das aminas influenciaram a reação de cura. Os métodos dinâmicos de Kissinger, Ozawa e de Barrett foram utilizados para calcular a energia de ativação dos sistemas onde se variou o anidrido. Observou-se que os anidridos mais reativos foram o DDS e maleico que apresentaram os menores valores de energias de ativação. No estudo da influência do catalisador, utilizou-se o método de Barrett para determinar as energias de ativação das reações com as diferentes aminas. A amina cicloaliafática (DABCO foi a mais reativa obtendo-se o menor valor de energia de ativação (Ea = 51 kJ.mol-1 e fator pré-exponencial (ln A0 = 9 s-1.In the present work, differential scanning calorimetry (DSC was used to investigate the curing reaction kinetics of epoxy resins produced from reaction of epoxidized soybean oil (ESO with cyclic anhydrides dodecenylsuccinic (DDS, maleic (MAL, phthalic (PA, succinic (SUC and hexahydrophthalic (CH, in the presence of tertiary amines such as triethylamine (TEA, N,N-dimethylaniline (ARO and 1,4-diazabicyclo [2,2,2] octane (DABCO. The heating rate, the nature and structure of anhydrides and amines were found to affect the curing reaction. The dynamic methods of Kissinger, Ozawa and Barrett were used to calculate the activation energy of the reactions where different anhydrides were used. DDS and maleic anhydrides were more reactive than the others

  15. Mixture Genotoxicity of 2,4-Dichlorophenoxyacetic Acid, Acrylamide, and Maleic Hydrazide on Human Caco-2 Cells Assessed with Comet Assay

    DEFF Research Database (Denmark)

    Syberg, Kristian; Binderup, Mona-Lise; Cedergreen, Nina;

    2015-01-01

    ), and maleic hydrazide (MH), in an experiment with a fixed ratio design setup. The genotoxic effects were assessed with the single-cell gel electrophoresis assay (comet assay) for both single chemicals and the ternary mixture. The concentration ranges used were 0-1.4, 0-20, and 0-37.7 mM for 2,4-D, AA, and MH...

  16. Infrared spectroscopic studies of the heterogeneous reaction of ozone with dry maleic and fumaric acid aerosol particles.

    Science.gov (United States)

    Nájera, Juan J; Percival, Carl J; Horn, Andrew B

    2009-10-28

    Dicarboxylic acids, either directly emitted or formed in chemical processes, are found to be a significant component of tropospheric aerosols. To assess any potential chemical transformation of short unsaturated dicarboxylic acids in tropospheric heterogeneous chemistry, maleic and fumaric acid were selected as surrogates in this study. A novel aerosol flow tube apparatus is employed to perform kinetic studies of the oxidation of these organic compounds by gas-phase ozone. The system consists of a particle generation system, a vertically oriented glass flow tube and an infrared observation White cell with a Fourier transform infrared (FTIR) spectrometer for the detection system. A flow of single component organic aerosols with mean diameters ranging between 0.7 and 1.1 microm is introduced in a flow tube, in which the particles are subsequently exposed to a known concentration of ozone for a controlled period of time. A band assignment of infrared vibrational frequencies for dry maleic and fumaric acid aerosol spectra is presented. These studies are complemented with off-line analysis on the reaction products. The reaction exhibited pseudo-first-order kinetics on gas product formation, and the pseudo-first-order rate coefficients displayed a Langmuir-Hinshelwood dependence on gas-phase ozone concentration for both materials. By assuming a Langmuir-Hinshelwood behaviour, the following parameters were obtained: for the reaction of maleic acid aerosols, K(O3) = (3.3 + 0.5) x 10(-16) cm3 molecule(-1) and k(I)(max) = (0.038 + 0.004) s(-1); for the reaction of fumaric acid aerosols, K(O3) = (1.6 + 0.5) x 10(-16) cm3 molecule(-1) and k(I)(max) = (0.048 + 0.007) s(-1), where K(O3) is a parameter that describes the partitioning of ozone to the particle surface and k is the maximum pseudo-first-order coefficient at high ozone concentrations. Apparent reactive uptake coefficients were estimated from the pseudo-first-order rate coefficient and a trend of decreasing uptake

  17. EFFECT OF SUBSTITUTION POSITION OF HYDROXY GROUP AT BENZOIC ACID ON THE LUMINESCENT AND DEGRADATION PROPERTIES OF POLY[DI(CARBOXYPHENYL) SUCCINATE-co-SEBACIC ANHYDRIDE]S

    Institute of Scientific and Technical Information of China (English)

    Jun Fan; Hong-liang Jiang; Kang-jie Zhu

    2007-01-01

    In this work, two new diacids, di(m-carboxyphenyl) succinate (m-dCPS) and di(o-carboxyphenyl) succinate (o-dCPS), were synthesized by reaction of m-, o-hydroxy benzoic acid with succinic chloride, respectively. Their corresponding copolymers with sebacic acid (SA), P(m-dCPS:SA) and P(o-dCPS:SA), were prepared by melt copolycondensation and characterized by NMR, UV and DSC methods. Compared with inherently fluorescent poly[di(p-carboxyphenyl) succinateco-sebacic anhydride] (P(p-dCPS:SA)), P(m-dCPS:SA) and P(o-dCPS:SA) displayed different luminescent properties. P(m-dCPS:SA) could emit fluorescence under the excitation of both visible and UV light, while P(o-dCPS:SA) could only emit fluorescence when excited with UV light. Degradation rate of the two new copolyanhydrides increased with the increase of SA fraction in the copolymers. In addition, P(o-dCPS:SA) degraded more rapidly than P(m-dCPS:SA) with the same composition. Typical surface-degradation characteristics of these copolyanhydrides were observed.

  18. Impact behaviour of nylon-rubber blends: 5. Influence of the mechanical properties of the elastomer

    OpenAIRE

    Borggreve, R.J.M.; Gaymans, R.J.; Schuijer, J.

    1989-01-01

    Blends of 90wt% nylon-6 and 10wt% impact modifier were prepared. As impact modifiers were used: EPDM (ethylene propylene diene monomer) rubber, EPM (ethylene propylene monomer) rubber, polyethylene, four poly(ether esters) and some commercial impact modifers. EPDM, EPM and polyethylene were functionalized with maleic anhydride. The mechanical properties of the impact modifiers were tested with both a torsion pendulum test and a tensile test. The notched impact strength of the blends was measu...

  19. Kinetics of Hydrolysis of Acetic Anhydride by In-Situ FTIR Spectroscopy: An Experiment for the Undergraduate Laboratory

    Science.gov (United States)

    Haji, Shaker; Erkey, Can

    2005-01-01

    A reaction kinetics experiment for the chemical engineering undergraduate laboratory course was developed in which in-situ Fourier Transfer Infrared spectroscopy was used to measure reactant and product concentrations. The kinetics of the hydrolysis of acetic anhydride was determined by experiments carried out in a batch reactor. The results…

  20. RAFT copolymerization of itaconic anhydride and 2-methoxyethyl acrylate: a multifunctional scaffold for preparation of “clickable” gold nanoparticles

    DEFF Research Database (Denmark)

    Javakhishvili, Irakli; Kasama, Takeshi; Jankova, Katja Atanasova

    2013-01-01

    RAFT copolymerization of 2-methoxyethyl acrylate and itaconic anhydride – a monomer derived from renewable resources – is carried out in a controlled fashion. The copolymer allows preparation of gold nanoparticles with abundant surficial carboxyl and alkyne functional groups that are dendronized ...... via Cu(i)-mediated “click” reaction....

  1. Nanoparticle self-assembly in mixtures of phospholipids with styrene/maleic acid copolymers or fluorinated surfactants

    Science.gov (United States)

    Vargas, Carolyn; Arenas, Rodrigo Cuevas; Frotscher, Erik; Keller, Sandro

    2015-12-01

    Self-assembling nanostructures in aqueous mixtures of bilayer-forming lipids and micelle-forming surfactants are relevant to in vitro studies on biological and synthetic membranes and membrane proteins. Considerable efforts are currently underway to replace conventional detergents by milder alternatives such as styrene/maleic acid (SMA) copolymers and fluorinated surfactants. However, these compounds and their nanosized assemblies remain poorly understood as regards their interactions with lipid membranes, particularly, the thermodynamics of membrane partitioning and solubilisation. Using 19F and 31P nuclear magnetic resonance spectroscopy, static and dynamic light scattering, and isothermal titration calorimetry, we have systematically investigated the aggregational state of a zwitterionic bilayer-forming phospholipid upon exposure to an SMA polymer with a styrene/maleic acid ratio of 3 : 1 or to a fluorinated octyl phosphocholine derivative called F6OPC. The lipid interactions of SMA(3 : 1) and F6OPC can be thermodynamically conceptualised within the framework of a three-stage model that treats bilayer vesicles, discoidal or micellar nanostructures, and the aqueous solution as distinct pseudophases. The exceptional solubilising power of SMA(3 : 1) is reflected in very low membrane-saturating and solubilising polymer/lipid molar ratios of 0.10 and 0.15, respectively. Although F6OPC saturates bilayers at an even lower molar ratio of 0.031, this nondetergent does not solubilise lipids even at >1000-fold molar excess, thus highlighting fundamental differences between these two types of mild membrane-mimetic systems. We rationalise these findings in terms of a new classification of surfactants based on bilayer-to-micelle transfer free energies and discuss practical implications for membrane-protein research.Self-assembling nanostructures in aqueous mixtures of bilayer-forming lipids and micelle-forming surfactants are relevant to in vitro studies on biological and

  2. Functionalyzed Polyampholytes on the Basis of Copolymers of N,N-Diallyl-N,N-dimethylammonium Chloride and Maleic Acid

    DEFF Research Database (Denmark)

    Vlasov, Petr; Chernyy, Sergey; Domnina, Nina

    2010-01-01

    Polyampholytes were prepared by radical copolymerization of N,N-diallyl-N,N-dimethylammonium chloride and maleic acid. The esterification and subsequent hydrazinolysis permitted to introduce hydrazide groups capable of formation of the coordination bond with copper ions. The formation of complex...... between the hydrazide groups of polyampholyte and Cu2+ ions was established by electronic spectroscopy. It was shown that the coordination of two hydrazide groups in the complex was hampered because of the polymeric nature of the ligand. It is shown that the created functionalized polyampholytes exhibit...... fungiostatic activity. The highest inhibiting effect on the growth of the pathogenic fungus Fusarium oxysporumis observed for complexes of the hydrazide-containing polyampholytes with Cu2+ ions....

  3. Laser-induced photochemical reaction of aqueous maleic acid solutions containing H{sub 2}O{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, Yuichi; Kawanishi, Shunichi; Suzuki, Nobutake [Japan Atomic Energy Research Inst., Neyagawa, Osaka (Japan). Osaka Lab. for Radiation Chemistry

    1995-03-01

    Hydroxy acid such as glycolic, tartaric and malic acids was directly produced by XeF-laser irradiation of the N{sub 2}-saturated maleic acid aqueous solution containing H{sub 2}O{sub 2}. The selectivities of these products at the maximum of tartaric acid were 71, 4, and 2% at H{sub 2}O{sub 2} feeding rate of 3.2 ml h{sup -1}, respectively. On the other hand, the irradiation of maleates such as dipotassium, calcium, and disodium greatly enhanced the selectivities of tartaric acid formation to 19%, and of malic acid formation to 13%, respectively, for dipotassium maleate. It may be considered from these results that the stability of the hydroxylated intermediate radical plays an important role for the efficient formations of tartaric and malic acids. (author).

  4. 界面改性剂对木橡塑混合物料流变特性的影响%Effects of interfacial modifier on rheological properties of wood/rubber/HDPE mixed materials

    Institute of Scientific and Technical Information of China (English)

    陈玲; 孙妍; 刘秀娟; 周秉亮; 程明娟; 徐信武

    2016-01-01

    To investigate the influence of coupling agents on the flow performance of wood/rubber/HDPE mixed raw ma⁃terials in manufacture of composites, maleic anhydride grafted polyethylene ( MAPE) and silane coupling agents ( Si69) were applied to modify the interface of the wood/rubber/HDPE composites. The adding amount of MAPE were 3%, 5%and 8%, and Si69 was 0.5%, 1%, 3% and 5%. The results showed significant influences of the two coupling agents on the rheological properties of the mixed raw materials and significant interactive effects between the two kinds of coupling agents. With 5% MAPE used alone, the mixed materials showed minimum shear stress and apparent viscosity, which means an optimal processing performance. When used together, 3% MAPE and 3% Si69 were proved to be the best com⁃bination.%为研究偶联剂对木粉、废旧橡胶和塑料组成的木橡塑三元混合物料流动性能的影响,分别采用3%、5%、8%的马来酸酐接枝聚乙烯( MAPE)和0.5%、1%、3%、5%的橡胶专用硅烷偶联剂( Si69)对三元混合物料进行表面处理。结果表明:两种偶联剂对复合物料体系的流变特性均具有显著影响,且二者之间存在显著的交互作用;单独使用MAPE,其质量分数在5%时混合物料的剪切应力和表观黏度值最小,加工性能最优;MAPE和Si69同时使用时,混合体系的流变性以MAPE质量分数和Si69质量分数均为3%的配合为最佳。

  5. 水性紫外光固化十三氟辛醇改性环氧树脂的合成与性能%Synthesis and properties of water-based UV-curable tridecafluorooctanol modified epoxy resin

    Institute of Scientific and Technical Information of China (English)

    吴业辉; 张力; 肖逸兴; 周子愉

    2013-01-01

    A water-based UV-curable tridecafluorooctanol modified epoxy resin prepolymer (F13-EMA) was synthesized by solution polymerization with E-44 epoxy resin, 2-(perfluorohexyl)ethanol, 2,4-toluene diisocyanate (TDI), and maleic anhydride (MA), and characterized by FT-IR. The thermal, optical, and mechanical properties as well as the hydrophobicity and oleophobicity of the F13-EMA were studied and compared with the fluorine-free epoxy maleate (EMA). The results indicated that as compared with the EMA, the F13-EMA has a nearly the same curing time, slightly decreased hardness and adhesion strength, but higher thermal stability. The impact strength of F13-EMA was improved from 75 kg·cm to 120 kg·cm, the surface energy reduced from 45.6 mN/m to 17.1 mN/m, and the contact angle increased from 40° to 104° for water and from 35° to 65° for glycol. The hydrophobicity and oleophobicity of the water-based UV-cured F13-EMA film are enhanced remarkably.%以E-44环氧树脂、十三氟辛醇、2,4-甲苯二异氰酸酯(TDI)和马来酸酐(MA)为原料,通过溶液聚合法合成了水性UV固化氟醇改性环氧树脂预聚体(F13-EMA),利用 FT-IR 对其结构进行了表征。与不含氟环氧顺丁烯酸酯(EMA)进行比较,研究了F13-EMA的热学、光学与力学性能以及疏水、疏油性能。结果表明,与 EMA 相比,F13-EMA 光固化时间近似,硬度和附着力稍有下降,但热稳定性提高,其冲击强度由75 kg·cm提高到120 kg·cm,表面自由能由45.6 mN/m降低到17.1 mN/m,对水、乙二醇的接触角分别由40°、35°增大到104°和65°。水性 UV固化F13-EMA膜的疏水、疏油性能大大提高。

  6. Synthesis of Poly(aryl amide imide)s Derived from o-diphenyltrimellitic Anhydride

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The synthesis and characterization of a series of novel poly(aryl amide imide)s based on o-diphenyltrimellitic anhydride are described.The poly(aryl amide-imide)s having inherent viscosities of 0.39-1.43dL/g in N-methyl-2-pyrrolidinone at 30℃,were prepared by polymerization with aromatic diamines in N,N-dimethylacetamide and subsequent chemical imidization.All the polymers were amorphous,readily soluble in aprotic polar solvents such as DMAC,NMP,DMF,DMSO,and m-cresol,and could be cast to form flexible and tough films.The glass trsanition temperatures were in the range of 284-336℃,and the temperatures for 5% weight loss in nitrogen were above 468℃.

  7. One-pot synthesis of thermoplastic mixed paramylon esters using trifluoroacetic anhydride.

    Science.gov (United States)

    Shibakami, Motonari; Tsubouchi, Gen; Sohma, Mitsugu; Hayashi, Masahiro

    2015-03-30

    Mixed paramylon esters prepared from paramylon (a storage polysaccharide of Euglena), acetic acid, and a long-chain fatty acid by one-pot synthesis using trifluoroacetic anhydride as a promoter and solvent were shown to have thermoplasticity. Size exclusion chromatography indicated that the mixed paramylon esters had a weight average molecular weight of approximately 4.9-6.7×10(5). Thermal analysis showed that these esters were stable in terms of the glass transition temperature (>90°C) and 5% weight loss temperature (>320°C). The degree of substitution of the long alkyl chain group, a dominant factor determining thermoplasticity, was controlled by tuning the feed molar ratio of acetic acid and long-chain fatty acid to paramylon. These results implied that the one-pot synthesis is useful for preparing structurally-well defined thermoplastic mixed paramylon esters with high molecular weight. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Effects of Amine and Anhydride Curing Agents on the VARTM Matrix Processing Properties

    Science.gov (United States)

    Grimsley, Brian W.; Hubert, Pascal; Song, Xiaolan; Cano, Roberto J.; Loos, Alfred C.; Pipes, R. Byron

    2002-01-01

    To ensure successful application of composite structure for aerospace vehicles, it is necessary to develop material systems that meet a variety of requirements. The industry has recently developed a number of low-viscosity epoxy resins to meet the processing requirements associated with vacuum assisted resin transfer molding (VARTM) of aerospace components. The curing kinetics and viscosity of two of these resins, an amine-cured epoxy system, Applied Poleramic, Inc. VR-56-4 1, and an anhydride-cured epoxy system, A.T.A.R.D. Laboratories SI-ZG-5A, have been characterized for application in the VARTM process. Simulations were carried out using the process model, COMPRO, to examine heat transfer, curing kinetics and viscosity for different panel thicknesses and cure cycles. Results of these simulations indicate that the two resins have significantly different curing behaviors and flow characteristics.

  9. Enhanced Activity of Nanocrystalline Beta Zeolite for Acylation of Veratrole with Acetic Anhydride.

    Science.gov (United States)

    Aisha Mahmood Abdulkareem, Al-Turkustani; Selvin, Rosilda

    2016-04-01

    Friedel-Craft acylation of veratrole using homogeneous acid catalysts such as AlCl3, FeCl3, ZnCl2, and HF etc. produces acetoveratrone, (3',4'-dimethoxyacetophenone), which is the intermediate for synthesis of papavarine alkaloids. The problems associated with these homogeneous catalysts can be overcome by using heterogeneous solid catalysts. Since acetoveratrone is a larger molecule, large pore Beta zeolites with smaller particle sizes are beneficial for the liquid-phase acylation of veratrole, for easy diffusion of reactants and products. The present study aims in the acylation of veratrole with acetic anhydride using nanocrystalline Beta Zeolite catalyst. A systematic investigation of the effects of various reaction parameters was done. The catalysts were characterized for their structural features by using XRD, TEM and DLS analyses. The catalytic activity of nanocrystalline Beta zeolite was compared with commercial Beta zeolite for the acylation and was found that nanocrystalline Beta zeolite possessed superior activity.

  10. Polycondensation of Tetrahydrofuran with Phthalic Anhydride Induced By a Proton Exchanged Montmorillonite Clay

    OpenAIRE

    Mohammed Belbachir; Mohammed Issam Ferrahi

    2003-01-01

    Abstract: “Maghnite†a montmorillonite sheet silicate clay, exchanged with protons to produce “H-Maghnite†is an efficient catalyst for polymerization of many vinylic and heterocyclic monomers (Belbachir, M. U.S. Patent. 066969.0101 –2001). The structure compositions of both “Maghnite†and “H-Maghnite†have been developed. This catalyst was used for the polycondensation of the tetrahydrofuran with phthalic anhydride. The polymerization was performed un...

  11. Crystal structure of O-benzyl-l-tyrosine N-carb-oxy anhydride.

    Science.gov (United States)

    Inada, Aya; Kanazawa, Hitoshi

    2017-04-01

    In the title compound, C17H15NO4 (alternative name; O-benzyl-l-tyrosine N-carb-oxy anhydride), the oxazolidine ring is planer, with an r.m.s. deviation of 0.039 Å. The benz-yloxy and benzyl rings are almost coplanar, making a dihedral angle of 0.078 (10)°, and are inclined to the oxazolidine ring by 59.16 (11) and 58.42 (11)°, respectively. In the crystal, mol-ecules are linked by N-H⋯O and C-H⋯O hydrogen bonds, forming ribbons propagating along [010]. The ribbons are linked by C-H⋯π inter-actions, forming a three-dimensional supra-molecular structure. The oxazolidine rings of adjacent ribbons are arranged into a layer parallel to the ab plane. This arrangement is favourable for the polymerization of the compound in the solid state.

  12. Poly(anhydride-esters) comprised exclusively of naturally occurring antimicrobials and EDTA: antioxidant and antibacterial activities.

    Science.gov (United States)

    Carbone-Howell, Ashley L; Stebbins, Nicholas D; Uhrich, Kathryn E

    2014-05-12

    Carvacrol, thymol, and eugenol are naturally occurring phenolic compounds known to possess antimicrobial activity against a range of bacteria, as well as antioxidant activity. Biodegradable poly(anhydride-esters) composed of an ethylenediaminetetraacetic acid (EDTA) backbone and antimicrobial pendant groups (i.e., carvacrol, thymol, or eugenol) were synthesized via solution polymerization. The resulting polymers were characterized to confirm their chemical composition and understand their thermal properties and molecular weight. In vitro release studies demonstrated that polymer hydrolytic degradation was complete after 16 days, resulting in the release of free antimicrobials and EDTA. Antioxidant and antibacterial assays determined that polymer release media exhibited bioactivity similar to that of free compound, demonstrating that polymer incorporation and subsequent release had no effect on activity. These polymers completely degrade into components that are biologically relevant and have the capability to promote preservation of consumer products in the food and personal care industries via antimicrobial and antioxidant pathways.

  13. Stereodynamic control of star-epoxy/anhydride crosslinking actuated by liquid-crystalline phase transitions.

    Science.gov (United States)

    Pin, Jean-Mathieu; Mija, Alice; Sbirrazzuoli, Nicolas

    2017-02-07

    The epoxy/anhydride copolymerization kinetics of an original star-epoxy monomer (TriaEP) was explored in dynamic heating mode using a series of isoconversional methods. Negative values of the apparent activation energy (Eα) related to an anti-Arrhenius behavior were observed. The transition from Arrhenius to anti-Arrhenius behavior and vice versa depending on the Eα of polymerization was correlated with the dynamics of mesophasic fall-in/fall-out events, physically induced transition (PIT) and chemically induced transition (CIT). This self-assembly phenomenon induces the generation of an anisotropic crosslinked architecture exhibiting both nematic discotic (ND) and nematic columnar (NC) organization. Particular emphasis was placed on evaluating the juxtaposition/contribution of the liquid-crystalline transitions to crosslinking, considering both the reaction dynamics and the macromolecular vision.

  14. The influence of tertiary amine accelerators on the curing behaviors of epoxy/anhydride systems

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Tao; Zhang, Chongfeng; Zhang, Junying, E-mail: zjybuct@gmail.com; Cheng, Jue

    2014-02-10

    Highlights: • The influences of two types of accelerators (BDMA and DMP-30) on curing reaction of DGEBF/MeHHPA systems were studied comparatively. • The activation energy and kinetic parameters of DGEBF/MeHHPA systems with accelerator content of 0.2 phr and 0.5 phr were calculated, respectively. • The dependence of autocatalytic and non-autocatalytic curing reaction on the loading of accelerators was discussed. • The non-catalytic curing reaction dominated absolutely in the curing process of DGEBF/MeHHPA systems when the accelerator contents were 0.2 phr. - Abstract: Accelerators have significant effects on the curing behaviors of epoxy/anhydride (diglycidyl ether of bisphenol-F/methylhexahydrophthalic anhydride, DGEBF/MeHHPA) systems. Non-isothermal DSC was used to investigate the influence of dimethyl benzylamine (BDMA, 0.2 phr/0.5 phr) and Tris-(dimethyl aminomethyl) phenol (DMP-30, 0.2 phr/0.5 phr) on the curing behaviors of DGEBF/MeHHPA systems, respectively. When the amount of accelerators was kept constant, the activation energy calculated by Kissinger method changed slightly in the presence of either BDMA or DMP-30. And, with increasing the accelerator content from 0.2 phr to 0.5 phr, the value of activation energy decreased from 115 kJ/mol to 85 kJ/mol. Furthermore, the calculation results of Málek method identified that all systems in this study fitted Sesták–Berggren (SB) model and the corresponding model parameters, m and n, were obtained. It was found that the contribution of autocatalytic reaction with low accelerator content (0.2 phr) was far less than that with high accelerator content (0.5 phr)

  15. Highly dispersed ruthenium nanoparticle-embedded mesoporous silica as a catalyst for the production of gamma-butyrolactone from succinic anhydride.

    Science.gov (United States)

    Chung, Sang-Ho; Eom, Hee-Jun; Kim, Min-Sung; Lee, Myung Suk; Lee, Kwan-Young

    2013-11-01

    In this study, a novel, strategic method was developed for the synthesis of a mesoporous silica catalyst embedded with ruthenium nanoparticles (RuNPs/SiO2) by combining the polyol and modified sol-gel methods. By applying this new procedure, uniformly synthesized ruthenium nanoparticles with an average size of 3.8 nm and 95% spherical shape were highly dispersed in the mesoporous silica support material. Coordinated carbonyl groups of PVP remaining from the synthesis of the RuNPs were effectively removed by the thermal treatment (calcined at 573 K for 4 h) and the sythesized RuNPs/SiO2 catalysts were reduced under hydrogen at 20 bar for 2 h. These catalysts were analyzed using transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), N2 adsorption-desorption, and X-ray diffraction (XRD). After the thermal treatment and the reduction procedure, the size and shape of the embedded RuNPs were nearly unchanged, and the catalyst was active in the liquid-phase hydrogenation of succinic anhydride (SAN) to selectively form y-butyrolactone (GBL) with a maximum yield of 90.1%. This novel catalyst preparation is a potentially useful method for the synthesis of metal nanoparticles as heterogeneous catalysts.

  16. Comparison of the efficacy of ethylene diamine tetraacetic acid and maleic acid in the removal of three calcium hydroxide intra-canal dressings: A spiral computerized tomography volumetric analysis

    Directory of Open Access Journals (Sweden)

    Mohan Thomas Nainan

    2013-01-01

    Full Text Available Aim: To assess the efficacy of 17% ethylene diamine tetra acetic acid and 7% maleic acid in the removal of 3 calcium hydroxide preparations placed as intracanal medicaments. Materials and Methods: The root canals of 60 single rooted premolars were prepared with a step back technique and randomly assigned into 3 experimental groups (n = 20. Group A was filled with plain calcium hydroxide mixed with distilled water in which barium sulfate was added for radio opacity, Group B was filled with Apexcal and Group C was filled with Metapex. After 7 days each group was divided into 2 sub groups (n = 10. The medicaments were retrieved with 17% EDTA (first sub group and 7% maleic acid (second sub group. Along with the above irrigants manual and ultrasonic agitation was used. The pre and post removal volume of medicaments in root canals were measured using spiral computerized tomography. The percentage difference was calculated and statistically analyzed using Kruskal Wallis and Mann Whitney U test. Results: 17% EDTA and 7% maleic acid efficiently removed calcium hydroxide, distilled water mixture (P = 0.218 and Apexcal (P = 0.684, whereas 7% maleic acid showed better retrieval capability of Metapex than 17% EDTA (P = 0.002. Conclusion: Calcium hydroxide, distilled water mixture and polyethylene glycol based calcium hydroxide were efficiently removed by 17% EDTA and 7% maleic acid. 7% maleic acid removed silicone oil based calcium hydroxide preparation better than 17% EDTA.

  17. Applications of Microwave in Organic Synthesis: An Improved One-step Synthesis of Metallophthalocyanines and a New Modified Microwave Oven for Dry Reactions

    OpenAIRE

    Nathalie Bar; Messaoud Hachemi; Mohamed Hammadi; Didier Villemin

    2001-01-01

    Metallophthalocyanine complexes are obtained quickly and efficiently by the reaction of phthalodinitrile with hydrated metallic salts without solvent and under microwave irradiation. The use of a modified commercial microwave oven to perform this type of reactions under dry conditions is described. Metallophthalocyanines and metallododecachlorophthalocyanines of some divalent metals can be also obtained from phthalic or tetrachlorophthalic anhydrides with hydrated metallic salt and urea under...

  18. Plastic Trash goes Biohybrid"-Rapid and Selective Functionalization of Inert Plastic Surfaces with Biomolecules

    DEFF Research Database (Denmark)

    Schiller, Stefan M; Kambhampati, Dev; Stengel, Gudrun

    2010-01-01

    The covalent functionalization of "inert" polymers such as polypropylene with biomolecules for biocompatible or biosensor surfaces is challenging. Here we present a powerful approach to covalently modify "inert" macromolecular surfaces with biomacromolecules reusing old plastic material. A specia...... with a thin reactive plasma polymerized maleic anhydride nanolayer network, which can be subsequently modified with biomolecules for various applications, e.g., in tissue engineering and as biochips...

  19. Antagonistic effects of ethyl methanesulfonate and maleic hydrazide in inducing somatic mutations in the stamen hairs of Tradescantia clone BNL 4430

    OpenAIRE

    市川, 定夫

    1998-01-01

    Mutagenic interaction between ethyl methanesulfonate (EMS; a monofunctional alkylating agent) and maleic hydrazide (MH; a promutagen activated into a mutagen in plants highly likely by peroxidase) was studied in the stamen hairs of Tradescantia clone BNL 4430, a blue/pink heterozygote. Since EMS has been shown to act synergistically with X rays in inducing mutations, and mutagenic synergisms have also been observed between X rays and MH by exposing to X rays before MH treatments, EMS and MH w...

  20. A STUDY OF SILICA-SUPPORTED CROSS-LINKED POLY(MALEIC ACID-CO-STYRENE)-PLATINUM COMPLEX IN THE HYDROGENATION OF p-CRESOL

    Institute of Scientific and Technical Information of China (English)

    CHEN Chunwei; WANG Xin; HUANG Meiyu; JIANG Yingyan

    1996-01-01

    A silica-supported cross-linked poly(maleic acid -co- styrene)-platinum complex (PMSPt) has been prepared and found to be active in the hydrogenation of p-cresol under mild conditions (303-323K, 1.01 × 105Pa). In this hydrogenation system water serves as a solvent and p-cresol can be converted to 4-methylcyclohexanol quantitatively via 4-methylcyclohexanone as intermediate.

  1. Modular access to vicinally functionalized allylic (thio)morpholinonates and piperidinonates by substrate-controlled annulation of 1,3-azadienes with hexacyclic anhydrides.

    Science.gov (United States)

    Braunstein, Hannah; Langevin, Spencer; Khim, Monique; Adamson, Jonathan; Hovenkotter, Katie; Kotlarz, Lindsey; Mansker, Brandon; Beng, Timothy K

    2016-09-21

    A modular substrate-controlled hexannulation of inherently promiscuous 1,3-azadienes with hexacyclic anhydrides, which affords versatile vicinally functionalized allylic lactams, in high yields, regio- and stereoselectivities is described.

  2. Whole slurry fermentation of maleic acid-pretreated oil palm empty fruit bunches for ethanol production not necessitating a detoxification process.

    Science.gov (United States)

    Jung, Young Hoon; Kim, In Jung; Kim, Hyun Kyung; Kim, Kyoung Heon

    2014-04-01

    The yield of ethanol from oil palm empty fruit bunches (EFB) was increased on exploiting maleic acid pretreatment combined with fermentation of the pretreated whole slurry. The optimized conditions for pretreatment were to expose EFB to a high temperature (190 °C) with 1 % (w/v) maleic acid for a short time duration (3 min ramping to the set temperature with no holding) in a microwave digester. An enzymatic digestibility of 60.9 % (based on theoretical glucose yield) was exhibited using pretreated and washed EFB after 48 h of hydrolysis. Simultaneous saccharification and fermentation (SSF) of the whole slurry of pretreated EFB for 48 h resulted in 61.3 % theoretical yield of ethanol based on the initial amount of glucan in untreated EFB. These results indicate that maleic acid is a suitable catalyst not requiring detoxification steps for whole slurry fermentation of EFB for ethanol production, thus improving the process economics. Also, the whole slurry fermentation can significantly increase the biomass utilization by converting sugar from both solid and liquid phases of the pretreated slurry.

  3. A comparative evaluation of smear layer removal by using edta, etidronic acid, and maleic acid as root canal irrigants: An in vitro scanning electron microscopic study

    Science.gov (United States)

    Kuruvilla, Aby; Jaganath, Bharath Makonahalli; Krishnegowda, Sahadev Chickmagaravalli; Ramachandra, Praveen Kumar Makonahalli; Johns, Dexton Antony; Abraham, Aby

    2015-01-01

    Aim: The purpose of this study is to evaluate and compare the efficacy of 17% EDTA, 18% etidronic acid, and 7% maleic acid in smear layer removal using scanning electron microscopic image analysis. Materials and Methods: Thirty, freshly extracted mandibular premolars were used. The teeth were decoronated to obtain working length of 17mm and instrumentation up to 40 size (K file) with 2.5% NaOCl irrigation between each file. The samples were divided into Groups I (17% ethylenediaminetetraacetic acid (EDTA)), II (18% etidronic acid), and III (7% maleic acid) containing 10 samples each. Longitudinal sectioning of the samples was done. Then the samples were observed under scanning electron microscope (SEM) at apical, middle, and coronal levels. The images were scored according to the criteria: 1. No smear layer, 2. moderate smear layer, and 3 heavy smear layer. Statistical Analysis: Data was analyzed statistically using Kruskal–Wallis analysis of variance (ANOVA) followed by Mann-Whitney U test for individual comparisons. The level for significance was set at 0.05. Results: The present study showed that all the three experimental irrigants removed the smear layer from different tooth levels (coronal, middle, and apical). Final irrigation with 7% maleic acid is more efficient than 17% EDTA and 18% etidronic acid in the removal of smear layer from the apical third of root canal. PMID:26069414

  4. Application of matrix solid-phase dispersion to the propham and maleic hydrazide determination in potatoes by differential pulse voltammetry and HPLC.

    Science.gov (United States)

    Arribas, Alberto Sánchez; Bermejo, Esperanza; Chicharro, Manuel; Zapardiel, Antonio

    2007-01-15

    The application of the matrix solid-phase dispersion (MSPD) process as sample treatment in connection with the electrochemical detection is studied for the first time. For this purpose, a novel methodology is introduced for the extraction of propham and maleic hydrazide herbicides from potatoes samples based in the MSPD process prior to their electrochemical detection. Potato samples disruption was done by blending them with C(8) bonded-phase and selective herbicide extraction was achieved by successive treatment of the blended with 50mM phosphate buffer pH 7.4 (for maleic hydrazide) and methanol (for propham). The extraction procedure efficiency was estimated using differential pulse voltammetry in potato samples spiked with the herbicides yielding recovery values of 98% and 68% for propham and maleic hydrazide, respectively. No significant adverse effect of the MSPD process was observed on the herbicides electrochemical signals. For comparison, recovery studies using HPLC with UV detection were carried out and a good correlation in the results obtained by using both techniques was observed.

  5. Evaluation of genotoxic activity of maleic hydrazide, ethyl methane sulfonate, and N-nitroso diethylamine in Tradescantia

    Directory of Open Access Journals (Sweden)

    Alvarez-Moya Carlos

    2001-01-01

    Full Text Available Objective. To assess the genotoxic activity of N-nitroso diethylamine (NDEA, maleic hydrazide (MH, and ethyl methane sulfonate (EMS using two systems: the comet assay on nuclei from Tradescantia, and the pink mutation test on Tradescantia staminal hairs (clone 4430. Material and Methods. Tradescantia cups was obtained from Laboratorio de Citogenética y Mutagénesis del Centro de Ciencias de la Atmósfera de la Universidad Nacional Autónoma de México and treated with: N-nitroso diethylamine (NDEA at 1, 5, 10 mM, maleic hidrazide (MH at 1, 5, 10 mM and ethyl methane sulfonate (EMS at 15, 30 and 45 mM; and used in both pink mutation assay and comet assay using cellular nuclei from Tradescantia staminal hairs. The observation of staminal hair was realized along eight days (6-14 after treatment, flowers produced day 14 after treatment were utilized done according to Underbrink. In previous reports on plants, were comet assay was used, breaking cellular wall and separating by centrifugation gradient are necessary. Here, nuclei from staminal hairs were obtained by squashing the cells (is not necessary to utilize to break special procedure cellular wall, collected using a nylon mesh of 80Mm and next the comet assay was applied. Student's T test was the statistical test used for analyzing the comet assay data. Results. Both assays showed a great sensitivity to the studied mutagens. A relationship between the dose-pink event and the dose-tail length was evident. Even though the Tradescantia mutation assay is a sensitive test with MH and EMS, low doses of NDEA were not able to induce a significant increase in the pink event frequencies; however, the comet assay was able to detect the mutagenic effect of NDEA at the same dose. Thus, it is clear that the comet assay is highly sensitive to the lowest dose of chemical mutagens. Conclusions. The comet assay on nuclei from Tradescantia staminal hairs is a useful tool to monitor genotoxic agents; it is simple

  6. Facile and Efficient Acetylation of Primary Alcohols and Phenols with Acetic Anhydride Catalyzed by Dried Sodium Bicarbonate

    Directory of Open Access Journals (Sweden)

    Fulgentius Nelson Lugemwa

    2013-12-01

    Full Text Available A variety of primary alcohols and phenols were reacted with acetic anhydride at room temperature in the presence of sodium bicarbonate to produce corresponding esters in good to excellent yields. The acetylation of 4-nitrobenzyl alcohol was also carried out using other bicarbonates and carbonates. The reaction in the presence of cesium bicarbonate and lithium carbonate gave 4-nitrobenzyl acetate in excellent yield, while in the presence of Na2CO3, K2CO3, Cs2CO3, or KHCO3 the yield was in the range of 80%–95%. Calcium carbonate and cobaltous carbonate did not promote the acetylation of 4-ntirobenzyl alcohol using acetic anhydride. The acetylation of 4-nitrobenzyl alcohol was carried out using ethyl acetate, THF, toluene, diethyl ether, dichloromethane and acetonitrile, and gave good yields ranging from 75%–99%. Toluene was the best solvent for the reaction, while diethyl ether was the poorest.

  7. Ficusmicrochlorin A-C, two new methoxy lactone chlorins and an anhydride chlorin from the leaves of Ficus microcarpa.

    Science.gov (United States)

    Lin, Huan-You; Chiu, Hsi-Lin; Lu, Te-Ling; Tzeng, Chih-Ying; Lee, Tzong-Huei; Lee, Ching-Kuo; Shao, Yi-Yuan; Chen, Chiy-Rong; Chang, Chi-I; Kuo, Yueh-Hsiung

    2011-01-01

    Two new methoxy lactone chlorins ficusmicrochlorin A (1) and ficusmicrochlorin B (2), and one new anhydride chlorin ficusmicrochlorin C (3), along with eight known pheophytins were isolated from the leaves of Ficus microcarpa. Their structures were determined by the extensive 1D- and 2D-NMR techniques. New pheophytin compound was rarely obtained from natural sources. In the past ten years, only three new natural pheophytins were characterized.

  8. Relationship between global indices of reactivity, electrodonating and electroaccepting powers, and the hammet constant in isatoic anhydride derivatives

    Indian Academy of Sciences (India)

    J S Durand-Niconoff; L Cruz-Kuri; M H Matus; J Correa-Basurto; J S Cruz-Sánchez; F R Ramos-Morales

    2011-09-01

    The possible correlation between Hammett’s constant (p), a characteristic parameter of functional groups with electrodonating or electroaccepting properties, and two indices of global reactivity were calculated in the gas phase. Parameters associated to a set of 22 structural variants of isatoic anhydride (2-3, 1-benzoxazin-2,4(1)-dione, ISA), replaced with diverse functional groups, were explored applying linear and quadratic statistical models for numerical analysis of the results.

  9. The Reaction of Crotonic Anhydride with Scots and Corsican Pine: Investigation of Kinetic Profiles and Determination of Activation Energies

    OpenAIRE

    Özmen, Nilgül; ÇETİN, Nihat Sami

    2014-01-01

    The kinetics of the reaction of crotonic anhydride with Scots pine (Pinus sylvestris) and Corsican pine (Pinus nigra) using pyridine as catalyst/solvent was investigated and activation energies for the initial reaction determined. Activation energies were calculated from the Arrhenius equation using rate data obtained from time-course experiments repeated at several temperatures. In one method, reaction constants (k) were determined experimentally, while in the other method initial rates were...

  10. A NOVEL COPOLYMER-BOUND CIS- DICARBONYLRHODIUM COMPLEX FOR THE CARBONYLATION OF METHANOL TO ACETIC ACID AND ACETIC ANHYDRIDE

    Institute of Scientific and Technical Information of China (English)

    YUAN Guoqing; CHEN Yuying; CHEN Rongyao

    1989-01-01

    A series of porous microspheres of linear and ethylene diacrylate (M ') cross-linked copolymers of 2 - vinylpyridine (V) and methyl acrylate (M) reacted with tetracarbonyldichlorodirhodium to form a series of cis-dicarbonylrhodium chelate complex (MVRh and MVM 'Rh). They are thermally stable yet very reactive in the carbonylation of methanol to acetic acid, and of methanol - acetic acid mixture to acetic acid and acetic anhydride with a selectivity of 100% under relatively mild and anhydrous conditions.

  11. Mixed Anhydride Intermediates in the Reaction of 5(4H)‐Oxazolones with Phosphate Esters and Nucleotides

    Science.gov (United States)

    Liu, Ziwei; Rigger, Lukas; Rossi, Jean‐Christophe; Sutherland, John D.

    2016-01-01

    Abstract 5(4H)‐Oxazolones can be formed through the activation of acylated α‐amino acids or of peptide C termini. They constitute potentially activated intermediates in the abiotic chemistry of peptides that preceded the origin of life or early stages of biology and are capable of yielding mixed carboxylic‐phosphoric anhydrides upon reaction with phosphate esters and nucleotides. Here, we present the results of a study aimed at investigating the chemistry that can be built through this interaction. As a matter of fact, the formation of mixed anhydrides with mononucleotides and nucleic acid models is shown to take place at positions involving a mono‐substituted phosphate group at the 3’‐ or 5’‐terminus but not at the internal phosphodiester linkages. In addition to the formation of mixed anhydrides, the subsequent intramolecular acyl or phosphoryl transfers taking place at the 3’‐terminus are considered to be particularly relevant to the common prebiotic chemistry of α‐amino acids and nucleotides. PMID:27534830

  12. Locally delivered salicylic acid from a poly(anhydride-ester): impact on diabetic bone regeneration.

    Science.gov (United States)

    Wada, Keisuke; Yu, Weiling; Elazizi, Mohamad; Barakat, Sandrine; Ouimet, Michelle A; Rosario-Meléndez, Roselin; Fiorellini, Joseph P; Graves, Dana T; Uhrich, Kathryn E

    2013-10-10

    Diabetes mellitus (DM) involves metabolic changes that can impair bone repair, including a prolonged inflammatory response. A salicylic acid-based poly(anhydride-ester) (SA-PAE) provides controlled and sustained release of salicylic acid (SA) that locally resolves inflammation. This study investigates the effect of polymer-controlled SA release on bone regeneration in diabetic rats where enhanced inflammation is expected. Fifty-six Sprague-Dawley rats were randomly assigned to two groups: diabetic group induced by streptozotocin (STZ) injection or normoglycemic controls injected with citrate buffer alone. Three weeks after hyperglycemia development or vehicle injection, 5mm critical sized defects were created at the rat mandibular angle and treated with SA-PAE/bone graft mixture or bone graft alone. Rats were euthanized 4 and 12weeks after surgery, then bone fill percentage in the defect region was assessed by micro-computed tomography (CT) and histomorphometry. It was observed that bone fill increased significantly at 4 and 12weeks in SA-PAE/bone graft-treated diabetic rats compared to diabetic rats receiving bone graft alone. Accelerated bone formation in normoglycemic rats caused by SA-PAE/bone graft treatment was observed at 4weeks but not at 12weeks. This study shows that treatment with SA-PAE enhances bone regeneration in diabetic rats and accelerates bone regeneration in normoglycemic animals.

  13. Reaction of octenylsuccinic anhydride with a mixture of granular starch and soluble maltodextrin.

    Science.gov (United States)

    Bai, Yanjie; Shi, Yong-Cheng

    2013-11-06

    The reaction of octenylsuccinic anhydride (OSA) with a mixture of granular waxy maize starch and soluble maltodextrin was investigated. OSA was reacted with a 1:1 (w/w) mixture of the granular starch and maltodextrin at OSA levels of 1.5, 3, 9, and 15% (wt% based on starch weight). After the first 0.5h of the reaction, degree of substitution (DS) on maltodextrin reached 0.021, 0.030, 0.080, and 0.10 for 1.5, 3, 9, and 15% OSA, respectively, whereas DS for granular starch was only 0.0020, 0.0087, 0.014, and 0.016. At 2h of the reaction, the bound OS ratio of maltodextrin to granular starch was 10.8 when OSA concentration was 1.5% and the ratio decreased to ca. 5 at higher OSA concentrations. OSA preferred to react with maltodextrin than semi-crystalline granular starch when both existed in the system. OSA reacted with maltodextrin at a much faster rate and to a greater extent than with granular starch, but a significant amount of OSA reacted with granular starch at 3-15% OSA concentrations.

  14. Structural properties of pepsin-solubilized collagen acylated by lauroyl chloride along with succinic anhydride.

    Science.gov (United States)

    Li, Conghu; Tian, Zhenhua; Liu, Wentao; Li, Guoying

    2015-10-01

    The structural properties of pepsin-solubilized calf skin collagen acylated by lauroyl chloride along with succinic anhydride were investigated in this paper. Compared with native collagen, acylated collagen retained the unique triple helix conformation, as determined by amino acid analysis, circular dichroism and X-ray diffraction. Meanwhile, the thermostability of acylated collagen using thermogravimetric measurements was enhanced as the residual weight increased by 5%. With the temperature increased from 25 to 115 °C, the secondary structure of native and acylated collagens using Fourier transform infrared spectroscopy measurements was destroyed since the intensity of the major amide bands decreased and the positions of the major amide bands shifted to lower wavenumber, respectively. Meanwhile, two-dimensional correlation spectroscopy revealed that the most sensitive bands for acylated and native collagens were amide I and II bands, respectively. Additionally, the corresponding order of the groups between native and acylated collagens was different and the correlation degree for acylated collagen was weaker than that of native collagen, suggesting that temperature played a small influence on the conformation of acylated collagen, which might be concluded that the hydrophobic interaction improved the thermostability of collagen.

  15. An efficient acetylation of dextran using in situ activated acetic anhydride with iodine

    Directory of Open Access Journals (Sweden)

    MUHAMMAD A. HUSSAIN

    2010-02-01

    Full Text Available A facile, efficient, cost-effective and solvent-free acetylation method has been developed for the acetylation of dextran. Dextran acetates were successfully synthesized using different molar ratios of acetic anhydride in the presence of iodine as a catalyst without the use of any solvent. The reactions were realized at 50 °C for 3 h under stirring and nitrogen. This efficient method yielded highly pure and organosoluble dextran esters. The reaction appears highly effective for obtaining higher degrees of substitution (DS with great efficiency. Under solvent-free conditions, dextran triacetates were efficiently synthesized. It was also observed that the molar ratio can easily control the DS of pendant groups onto the polymer backbone. Hence, a range of products with varying DS were successfully designed, purified and characterized. Covalent attachment of the pendant groups onto the polymer backbone was verified by spectroscopic techniques. Thermogravimetric analysis indicated that the obtained dextran esters were thermally as stable as dextran. The DS of the pendant groups onto the polymer backbone was calculated using standard acid base titration after saponification. Furthermore, all products were thoroughly characterized by thermal analysis (TG and DTG, and FTIR and 1H-NMR spectroscopic analysis.

  16. Dodecenylsuccinic anhydride derivatives of gum karaya (Sterculia urens): preparation, characterization, and their antibacterial properties.

    Science.gov (United States)

    Padil, Vinod Vellora Thekkae; Senan, Chandra; Černík, Miroslav

    2015-04-15

    Esterifications of the tree-based gum, gum karaya (GK), using dodecenylsuccinic anhydride (DDSA) were carried out in aqueous solutions. GK was deacetylated using alkali treatment to obtain deacetylated gum karaya (DGK). The DGK and its DDSA derivative were characterized using gel permeation chromatography/multiangle laser light scattering (GPC/MALLS), attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), scanning electron microscopy (SEM), proton nuclear magnetic resonance spectroscopy ((1)H NMR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) analysis, and rheological studies. The degree of substitution was found to be 10.25% for DGK using (1)H NMR spectroscopy. The critical aggregation concentration of DDSA-DGK was determined using dye solubilization and surface tension methods. The antibacterial activity of the DDSA-DGK derivative was then investigated against Gram-negative Escherichia coli and Pseudomonas aeruginosa and Gram-positive Staphylococcus aureus. The DDSA-DGK derivative has the potential for use as a stabilizing agent in food and nonfood applications. It can also be developed as an antibacterial agent.

  17. Crystal structure of γ-methyl l-glutamate N-carb-oxy anhydride.

    Science.gov (United States)

    Kanazawa, Hitoshi; Inada, Aya; Sakon, Aya; Uekusa, Hidehiro

    2015-01-01

    In the title compound, C7H9NO5, alternative name N-carb-oxy-l-glutamic anhydride γ-methyl ester, the oxazolidine ring is essentially planar with a maximum deviation of 0.020 (3) Å. In the crystal, mol-ecules are linked by N-H⋯O hydrogen bonds between the imino group and the carbonyl O atom in the methyl ester group, forming a tape structure along the a-axis direction. The tapes are linked by C-H⋯O inter-actions into a sheet parallel to the ac plane. The tapes are also stacked along the b axis with short contacts between the oxazolidine rings [C⋯O contact distances = 2.808 (4)-3.060 (4) Å], so that the oxazolidine rings are arranged in a layer parallel to the ab plane. This arrangement of the oxazolidine rings is very preferable for the polymerization of the title compound in the solid state.

  18. RING OPENING COPOLYMERIZATION OF SUCCINIC ANHYDRIDE-ETHYLENE OXIDE BY Al (Ⅲ) ORGANOMETALLIC CATALYSTS

    Institute of Scientific and Technical Information of China (English)

    CHEN Xianhai; ZHANG Yifeng; SHEN Zhiquan

    1997-01-01

    Ring opening copolymerization of succinic anhydride (SA) with ethylene oxide (EO)was successfully carried out by using a series of aluminum-based catalyst in 1,4-dioxane at 62±2℃. The results showed that in-situ AlR3-H2O (R=ethyl, iso-butyl) catalysts gave higher molecular weight ((-M)w ~ 104), while Al(OR)3 catalysts gave the higher alternating copolymer structure with slightly lower molecular weight. The in-situ AlR3-H2O systems have been evaluated in more detail for the reaction which showed the optimum H2O/Al molar ratio to be 0.5. The copolymers with different composition (FSA/FEO = 36/64 to 45/55 mol/mol) were synthesized by using different monomer feed ratio. The melting point (Tm), glass transition temperature (Tg) and enthalpy of fusion (ΔHf) of these copolymers are depended on the copolymer composition and in the range of 87~ 102℃,-12 ~ -18℃, and 37 ~ 66J/g, respectively. The second heating scan of DSC also indicated that the higher alternating copolymer was more easily recrystallized. The onset decomposition temperature was more than 300℃ under nitrogen and influenced by the copolymer composition.

  19. Acetylation of Wood Flour from Four Wood Species Grown in Nigeria Using Vinegar and Acetic Anhydride

    Directory of Open Access Journals (Sweden)

    Yakubu Azeh

    2013-01-01

    Full Text Available Effect of acetylation on pretreated wood flour of four different wood species, Boabab (Adansonia digitata, Mahoganny (Daniella oliveri, African locust bean (Parkia biglobosa and Beech wood (Gmelina arborea, had been investigated. The first batch of wood species were acetylated using acetic anhydride while the second batch were acetylated with commercial vinegar. Both experiments were conducted in the presence of varying amount of CaCl2 as catalyst and at temperature of 120°C for 3 h. The success of acetylation was determined based on Weight Percent Gain for each sample treated with either chemicals used. FT-IR, a veritable tool was used for the analysis of both treated and untreated samples to further investigate the success of acetylation. The results showed the presence of important band such as carbonyl absorptions at 1743, 1744, 1746, 1731, 1718 and 1696 cm−1 as appeared separately in the spectra of acetylated samples, confirming esterification occurred. The purpose of this work was to investigate the applicability of vinegar for acetylation of lignocellulosic fibers. Blends/composites were prepared by solution casting and their kinetics investigated in distilled water. The results indicated they could be used in outdoor applications such as, decking and packaging.

  20. Apical microleakage of different root canal sealers after use of maleic acid and EDTA as final irrigants.

    Science.gov (United States)

    Ulusoy, Ozgür Ilke; Nayir, Yelda; Celik, Kezban; Yaman, Sis Darendeliler

    2014-01-01

    This study aimed to compare the effects of ethylenediaminetetraacetic acid (EDTA) and maleic acid (MA) on the sealing ability of various root canal sealers. Eighty root canals were instrumented and irrigated with either EDTA or MA. They were divided into eight experimental groups and obturated as follows: Group 1: MA + Hybrid Root SEAL/gutta-percha. Group 2: EDTA + Hybrid Root SEAL/gutta-percha. Group 3: MA + iRoot SP/gutta-percha. Group 4: EDTA + iRoot SP/gutta-percha. Group 5: MA + EndoREZ/EndoREZ points. Group 6: EDTA + EndoREZ/EndoREZ points. Group 7: MA + AH Plus/gutta-percha. Group 8: EDTA + AH Plus/gutta-percha. Another ten roots were used as negative and positive controls. The microleakage of each sample was measured at 2-min intervals for 8 min using the fluid filtration method. Data were statistically analyzed with one-way ANOVA, post-hoc Tukey, and paired-samples t tests. The minimum microleakage values were obtained from the teeth obturated with AH Plus and EndoREZ selaers (p EDTA in terms of microleakage (p EDTA. The type of final irrigation solution seems to influence the postobturation apical seal. Use of AH Plus and EndoREZ sealers showed better sealing ability compared with IRoot SP and Hybrid Root SEAL.

  1. COPOLYMERS OF 2-ACRYLAMIDO-2-METHYL-1-PROPANESULFONIC ACID/MALEIC ACID: SYNTHESIS, CHARACTERIZATION AND ANTIMICROBIAL ACTIVITY

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    2-Acrylamido-2-methyl-1-propanesulfonic acid (AMPS),and maleic acid (MA)copolymerized with different feed ratios using N,N-dimethylformamide as a solvent and benzoyl peroxide (Bz2O2) as an initiator at 70℃.Structure and composition of copolymers for a wide range of monomer feed were determined by elemental analysis (content of N for AMPS-units).Monomer reactivity ratios for AMPS(M1)-MA(M2) pair were determined by the application of conventional lineartion methods such as Fineman-Ross(F-R),Kelen-Tüd(o)s(KT)and Extended Kxtended Kelen-Tüd(o)s(EKT) and a nonlinear error invariable model method using a computer program RREVM.The characterizations were done by Fourier transform infrared spectroscopy (FTIR),differential scanning calorimetry (DSC) thermal gravimetry analysis (TGA),and and Ⅹ-ray diffraction.The antimicrobial effects of polymers were also tested on various bacteria,and yeast.

  2. Styrene-maleic acid-copolymer conjugated zinc protoporphyrin as a candidate drug for tumor-targeted therapy and imaging.

    Science.gov (United States)

    Fang, Jun; Tsukigawa, Kenji; Liao, Long; Yin, Hongzhuan; Eguchi, Kanami; Maeda, Hiroshi

    2016-01-01

    Previous studies indicated the potential of zinc protoporphyrin (ZnPP) as an antitumor agent targeting to the tumor survival factor heme oxygenase-1, and/or for photodynamic therapy (PDT). In this study, to achieve tumor-targeted delivery, styrene-maleic acid-copolymer conjugated ZnPP (SMA-ZnPP) was synthesized via amide bond, which showed good water solubility, having ZnPP loading of 15%. More importantly, it forms micelles in aqueous solution with a mean particle size of 111.6 nm, whereas it has an apparent Mw of 65 kDa. This micelle formation was not detracted by serum albumin, suggesting it is stable in circulation. Further SMA-ZnPP conjugate will behave as an albumin complex in blood with much larger size (235 kDa) by virtue of the albumin binding property of SMA. Consequently, SMA-ZnPP conjugate exhibited prolonged circulating retention and preferential tumor accumulation by taking advantage of enhanced permeability and retention (EPR) effect. Clear tumor imaging was thus achieved by detecting the fluorescence of ZnPP. In addition, the cytotoxicity and PDT effect of SMA-ZnPP conjugate was confirmed in human cervical cancer HeLa cells. Light irradiation remarkably increased the cytotoxicity (IC50, from 33 to 5 μM). These findings may provide new options and knowledge for developing ZnPP based anticancer theranostic drugs.

  3. Prolonged Hypocalcemic Effect by Pulmonary Delivery of Calcitonin Loaded Poly(Methyl Vinyl Ether Maleic Acid Bioadhesive Nanoparticles

    Directory of Open Access Journals (Sweden)

    J. Varshosaz

    2014-01-01

    Full Text Available The purpose of the present study was to design a pulmonary controlled release system of salmon calcitonin (sCT. Therefore, poly(methyl vinyl ether maleic acid [P(MVEMA] nanoparticles were prepared by ionic cross-linking method using Fe2+ and Zn2+ ions. Physicochemical properties of nanoparticles were studied in vitro. The stability of sCT in the optimized nanoparticles was studied by electrophoretic gel method. Plasma calcium levels until 48 h were determined in rats as pulmonary-free sCT solution or nanoparticles (25 μg·kg−1, iv solution of sCT (5 μg·kg−1, and pulmonary blank nanoparticles. The drug remained stable during fabrication and tests on nanoparticles. The optimized nanoparticles showed proper physicochemical properties. Normalized reduction of plasma calcium levels was at least 2.76 times higher in pulmonary sCT nanoparticles compared to free solution. The duration of hypocalcemic effect of pulmonary sCT nanoparticles was 24 h, while it was just 1 h for the iv solution. There was not any significant difference between normalized blood calcium levels reduction in pulmonary drug solution and iv injection. Pharmacological activity of nanoparticles after pulmonary delivery was 65% of the iv route. Pulmonary delivery of P(MVEMA nanoparticles of sCT enhanced and prolonged the hypocalcemic effect of the drug significantly.

  4. Synthesis, growth, structural, optical, thermal and mechanical properties of an organic Urea maleic acid single crystals for nonlinear optical applications

    Science.gov (United States)

    Vinothkumar, P.; Kumar, R. Mohan; Jayavel, R.; Bhaskaran, A.

    2016-07-01

    A potential organic urea maleic acid (UMA) was synthesized and single crystals were grown at room temperature by slow evaporation and seed rotation methods. The grown crystal has been subjected to single crystal XRD analysis and found to have been crystallized in a noncentrosymmetric monoclinic crystal system with Cc as space group. The High resolution X-ray diffraction analysis revealed that the specimen is free from structural grain boundaries. The transparency of the grown crystal was confirmed by optical absorption and transmittance spectra with lower cut-off wavelength of 285 nm. The microhardness test was carried out on different planes to study the load dependent hardness values. The dislocation density of the UMA crystal was estimated from the etching studies. The dielectric permittivity and dielectric loss of the grown crystal was carried out as a function of frequency for different temperatures along three crystallographic axes. Thermal properties of UMA crystals were studied by TG-DTA analysis and it is stable upto 112 °C. The laser induced surface damage threshold of the grown crystal was measured using Nd: YAG laser. The birefringence of the crystal measured in the visible region was found to vary with the wavelength. The particle size dependent SHG of the sample was measured with different input energies by Kurtz's powder method using Nd:YAG laser.

  5. Detection of unexpected frauds: Screening and quantification of maleic acid in cassava starch by Fourier transform near-infrared spectroscopy.

    Science.gov (United States)

    Fu, Hai-Yan; Li, He-Dong; Xu, Lu; Yin, Qiao-Bo; Yang, Tian-Ming; Ni, Chuang; Cai, Chen-Bo; Yang, Ji; She, Yuan-Bin

    2017-07-15

    Fourier transform near-infrared (FT-NIR) spectroscopy and chemometrics were adopted for the rapid analysis of a toxic additive, maleic acid (MA), which has emerged as a new extraneous adulterant in cassava starch (CS). After developing an untargeted screening method for MA detection in CS using one-class partial least squares (OCPLS), multivariate calibration models were subsequently developed using least squares support vector machine (LS-SVM) to quantitatively analyze MA. As a result, the OCPLS model using the second-order derivative (D2) spectra detected 0.6%(w/w) adulterated MA in CS, with a sensitivity of 0.954 and specificity of 0.956. The root mean squared error of prediction (RMSEP) was 0.192(w/w, %) by using the standard normal variate (SNV) transformation LS-SVM. In conclusion, the potential of FT-NIR spectroscopy and chemometrics was demonstrated for application in rapid screening and quantitative analysis of MA in CS, which also implies that they have other promising applications for untargeted analysis. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Investigation on the Cellular Structure and Mechanical Properties of SGF/PP Foam Composites Modified with PP-g-MAH%PP-g-MAH改性SGF/PP泡沫复合材料的结构与力学性能研究

    Institute of Scientific and Technical Information of China (English)

    杨继年; 李子全

    2012-01-01

    The short glass fiber (SGF)/polypropylene (PP) foam composites modified with maleic anhydride grafted PP (PP-g-MAH) were prepared via post-foaming process in designed dies. The influence of PP-g-MAH content on the cellular morphologies, microstructures and mechanical properties of composites were investigated. The results show that the outstanding improvement in foaming effect is realized by the addition of PP-g-MAH with a 35% reduction for average cell size and nearly four-fold increase in cell density. The compatibilities between SGF and PP are improved and their interfacial adhesion is enhanced significantly by the surface pretreatment of coupling agent as well as PP-g-MAH. The flexural strength of SGF/PP foam composites is increased first and then decreased. However, the impact strength exhibits the trend of rapid increasing and then moderating with the increase of PP-g-MAH.%采用型内二次发泡工艺制备了马来酸酐接枝聚丙烯(PP-g-MAH)共混改性短玻璃纤维(SGF)/聚丙烯(PP)泡沫复合材料,考察了PP-g-MAH的含量对复合材料的泡孔形貌、微观结构和力学性能的影响.结果表明:PP-g-MAH的引入改善了泡沫体的发泡效果,平均孔径减小了约35%,泡孔密度提高近4倍且分布均匀;偶联剂的表面包覆和PP-g-MAH的共同作用改善了SGF与PP的相容性,显著增强了两者的界面结合;随SGF含量增加,SGF/PP泡沫复合材料的抗弯强度先增大后减小,而冲击强度则呈现先急剧增加而后趋缓的变化趋势.

  7. Synthesis and properties of a novel bio-based polymer from modified soybean oil

    Science.gov (United States)

    Li, Y. T.; Yang, L. T.; Zhang, H.; Tang, Z. J.

    2017-02-01

    Maleated acrylated epoxidized soybean oil (MAESO) was prepared by acrylated epoxidized soybean oil (AESO) and maleic anhydride. AESO were obtained by the reaction of epoxidized soybean oil (ESO) with acrylic acid as the ring-opening reagent. The polymer was prepared by MAESO react with styrene. The structures of the products were studied by Fourier transformation infrared spectrometer (FT-IR), and were consistent with the theoretical structures. Swelling experiment indicated that the crosslinking degree increased with increasing epoxy value of ESO. Thermal properties was tested by thermo-gravimetric analysis (TG) and differential scanning calorimetry analysis (DSC), indicating that glass transition temperature (Tg) of the polymer increased with increasing epoxy value of ESO, and thermal stability of polymer have a good correlation with the crosslinking degree. Mechanical properties analysis presented that tensile strength and impact strength affected by epoxy value of ESO. With the increase of epoxy value, the tensile strength increase, while the impact strength decrease. The property of the polymer ranged from elastomer to plastic character depended on the functionality of the ESO.

  8. Efficient pollutants removal by amino-modified nanocellulose impregnated with iron oxide

    Directory of Open Access Journals (Sweden)

    Taleb Khaled A.

    2016-01-01

    Full Text Available A novel adsorbents NC-PEG, obtained by the modification of nanocellulose (NC with PEG-6-arm amino polyethylene glycol (PEG-NH2 via maleic anhydride (MA linker, was used for the removal of Cd2+ and Ni2+ from water. Subsequent precipitation of goethite (FO on NC-PEG produced NC-PEG/FO adsorbent which was used for As(V and As(III removal. In a batch test, the influence of pH, contact time, initial ion concentration and temperature on adsorption efficiency were studied. The maximum adsorption capacities found for Cd2+ and Ni2+, obtained by the use of Langmuir model, were 37.9 and 32.4 mg g−1 at 25 °C, respectively. Also, high As(V and As(III removal capacity of 26.0 and 23.6 mg g-1 were obtained. Thermodynamic parameters indicate endothermic, feasible and spontaneous nature of adsorption process. Kinetic study, i.e. fitting by Weber-Morris model predicted intra-particle diffusion as a rate-controlling step. Multi-cycle reusability of both NC-PEG and NC-PEG/FO, significantly affects the affordability of techno-economic indicators for consideration of their possible application. [Ministry of Education, Science and Technological developments of the Republic of Serbia, Project No. 172013, and University of Defence, Republic of Serbia, project VA-TT/4/16-18

  9. Preparation and Characterization of Films Extruded of Polyethylene/Chitosan Modified with Poly(lactic acid)

    Science.gov (United States)

    Quiroz-Castillo, Jesús Manuel; Rodríguez-Félix, Dora Evelia; Grijalva-Monteverde, Heriberto; Lizárraga-Laborín, Lauren Lucero; Castillo-Ortega, María Mónica; del Castillo-Castro, Teresa; Rodríguez-Félix, Francisco; Herrera-Franco, Pedro Jesús

    2014-01-01

    The use of mixtures of synthetic and natural polymers is a potential option to reduce the pollution by plastic waste. In this work, the method for the chemical modification of chitosan with poly(lactic acid) was developed; then, the preparation of films of blends of polyethylene and chitosan-poly(lactic acid) produced by an extrusion method using polyethylene-graft maleic anhydride as a compatibilizer. It was possible to obtain films with a maximum content of 20 wt% and 30 wt%, chitosan, with and without compatibilizer, respectively. Scanning electron microscope (SEM) analysis showed a homogeneous surface on all films. The addition of the compatibilizer had a significant effect on the mechanical properties of the films, such as an increase in Young’s modulus and a decrease in the elongation at break; additionally, the compatibilizer promotes thermal degradation in a single step and gives the film a slight increase in thermal resistance. These results are attributed to an improved interaction in the interface of polyethylene and chitosan-poly(lactic acid), promoted by the compatibilizer. PMID:28787928

  10. Preparation and Characterization of Films Extruded of Polyethylene/Chitosan Modified with Poly(lactic acid

    Directory of Open Access Journals (Sweden)

    Jesús Manuel Quiroz-Castillo

    2014-12-01

    Full Text Available The use of mixtures of synthetic and natural polymers is a potential option to reduce the pollution by plastic waste. In this work, the method for the chemical modification of chitosan with poly(lactic acid was developed; then, the preparation of films of blends of polyethylene and chitosan-poly(lactic acid produced by an extrusion method using polyethylene-graft maleic anhydride as a compatibilizer. It was possible to obtain films with a maximum content of 20 wt% and 30 wt%, chitosan, with and without compatibilizer, respectively. Scanning electron microscope (SEM analysis showed a homogeneous surface on all films. The addition of the compatibilizer had a significant effect on the mechanical properties of the films, such as an increase in Young’s modulus and a decrease in the elongation at break; additionally, the compatibilizer promotes thermal degradation in a single step and gives the film a slight increase in thermal resistance. These results are attributed to an improved interaction in the interface of polyethylene and chitosan-poly(lactic acid, promoted by the compatibilizer.

  11. Structural properties of pepsin-solubilized collagen acylated by lauroyl chloride along with succinic anhydride

    Energy Technology Data Exchange (ETDEWEB)

    Li, Conghu [The Key Laboratory of Leather Chemistry and Engineering of Ministry of Education, Sichuan University, Chengdu 610065 (China); College of Life Sciences, Anqing Normal University, Anqing 246011 (China); Tian, Zhenhua; Liu, Wentao [The Key Laboratory of Leather Chemistry and Engineering of Ministry of Education, Sichuan University, Chengdu 610065 (China); Li, Guoying, E-mail: liguoyings@163.com [The Key Laboratory of Leather Chemistry and Engineering of Ministry of Education, Sichuan University, Chengdu 610065 (China)

    2015-10-01

    The structural properties of pepsin-solubilized calf skin collagen acylated by lauroyl chloride along with succinic anhydride were investigated in this paper. Compared with native collagen, acylated collagen retained the unique triple helix conformation, as determined by amino acid analysis, circular dichroism and X-ray diffraction. Meanwhile, the thermostability of acylated collagen using thermogravimetric measurements was enhanced as the residual weight increased by 5%. With the temperature increased from 25 to 115 °C, the secondary structure of native and acylated collagens using Fourier transform infrared spectroscopy measurements was destroyed since the intensity of the major amide bands decreased and the positions of the major amide bands shifted to lower wavenumber, respectively. Meanwhile, two-dimensional correlation spectroscopy revealed that the most sensitive bands for acylated and native collagens were amide I and II bands, respectively. Additionally, the corresponding order of the groups between native and acylated collagens was different and the correlation degree for acylated collagen was weaker than that of native collagen, suggesting that temperature played a small influence on the conformation of acylated collagen, which might be concluded that the hydrophobic interaction improved the thermostability of collagen. - Highlights: • Acylated collagen retained the unique triple helix conformation. • Acylated collagen had stronger thermostability than native collagen. • Amide I was the most sensitive band to the temperature for acylated collagen. • Amide II was the most sensitive band to the temperature for native collagen. • Auto-peak at 1680 cm{sup −1} for acylated collagen disappeared at higher temperature.

  12. Trimellitic anhydride-conjugated serum albumin activates rat alveolar macrophages in vitro

    Directory of Open Access Journals (Sweden)

    Bloksma Nanne

    2006-06-01

    Full Text Available Abstract Background Occupational exposure to airborne low molecular weight chemicals, like trimellitic anhydride (TMA, can result in occupational asthma. Alveolar macrophages (AMs are among the first cells to encounter these inhaled compounds and were previously shown to influence TMA-induced asthma-like symptoms in the Brown Norway rat. TMA is a hapten that will bind to endogenous proteins upon entrance of the body. Therefore, in the present study we determined if TMA and TMA conjugated to serum albumin induced the production of the macrophage mediators nitric oxide (NO, tumour necrosis factor (TNF, and interleukin 6 (IL-6 in vitro using the rat AM cell line NR8383 and primary AMs derived from TMA-sensitized and naïve Brown Norway rats. Methods Cells were incubated with different concentrations of TMA, TMA conjugated to bovine serum albumin (BSA, and BSA as a control for 24 h and the culture supernatant was analyzed for mediator content. Results TMA alone was not able to induce the production of mediators by NR8383 cells and primary AMs from sensitized and sham-treated rats. TMA-BSA, on the contrary, dose-dependently stimulated the production of NO, TNF, and IL-6 by NR8383 cells and of NO and TNF, but not IL-6, by primary AMs independent of sensitization. Conclusion Results suggest that although TMA is a highly reactive compound, conjugation to a suitable protein is necessary to induce mediator production by AMs. Furthermore, the observation that effects of TMA-BSA were independent of sensitization suggests involvement of an immunologically non-specific receptor. In the discussion it is argued that a macrophage scavenger receptor is a likely candidate.

  13. Evaporative Derivatization of Phenols with 2-Sulfobenzoic Anhydride for Detection by MALDI-MS

    Science.gov (United States)

    Yao, Yuanyuan; Wang, Poguang; Giese, Roger

    2014-01-01

    RATIONALE Phenols are an important class of analytes, for example as bioactive environmental contaminants. Towards a goal of improving their detection by MALDI-TOF-MS or MALDI-TOF/TOF-MS, we studied their derivatization with 2-sulfobenzoic anhydride (SBA). We chose SBA for this purpose since it is commercially available, inexpensive, and forms an anionic derivative. METHODS In selected conditions developed here for phenols, a reaction mixture of one or more of such compounds in acetonitrile containing SBA and 4-dimethylaminopyridine (DMAP) is evaporated to a solid, heated at 60°C for 1 h, redissolved in 50% acetonitrile containing matrix, spotted onto a MALDI target, and subjected to negative ion MALDI-TOF/TOF-MS. RESULTS While conventional (solution-phase) reaction of 4-phenylphenol (model analyte) with SBA and DMAP only gave a 47% yield of SBA-tagged 4-phenylphenol, evaporative derivatization as above gave a 96% yield, and 25 pmol (4.3 ng) of 4-phenylphenol could be detected in this way by MALDI-TOF/TOF-MS at S/N = 260, whereas even 1 nmol of the nonderivatized phenol was not detected in the absence of derivatization. A wide range of responses was observed when a mixture of 15 phenols was derivatized, with the higher responses coming from phenols with a pKa value above 9. Without derivatization, phenols with pKa values below 5 were the most readily detected. CONCLUSION Evaporative derivatization with SBA (a convenient reagent) can improve the detection of phenols with relatively high pKa values (above 9) by negative ion MALDI-TOF-MS, and accomplish this in the absence of post-derivatization reaction cleanup. PMID:24519828

  14. Trimellitic anhydride (TMA) dust induces airway obstruction and eosinophilia in non-sensitized guinea pigs.

    Science.gov (United States)

    Larsen, Christen P; Regal, Jean F

    2002-09-02

    Trimellitic anhydride (TMA) causes asthma after a latency period of sensitization. In non-sensitized humans and animals, limited studies indicate that TMA exposure may also cause symptoms of asthma without a latency period. Our previous studies (J. Pharmacol. Exp. Ther. 296 (2001) 284) in a guinea pig model of TMA-induced asthma demonstrated that sensitization and the complement system were required for eosinophilia. TMA conjugated to guinea pig serum albumin (TMA-GPSA) was used to elicit the response. Since occupational exposure to TMA occurs by inhalation of dust, the present studies determined if exposure to TMA dust in a non-sensitized guinea pig elicited airway obstruction and inflammation, and whether a significantly greater response occurred after a latency period of sensitization. Guinea pigs were intradermally injected with either corn oil (non-sensitized animals) or 30% TMA (sensitized animals). Three weeks later they were challenged by intratracheal insufflation with 1 mg TMA dust or lactose dust (control) using a dry powder delivery device. Pulmonary resistance, dynamic lung compliance, mean arterial blood pressure and heart rate were monitored for 10 min. In non-sensitized guinea pigs, significant increases in pulmonary resistance and decreases in dynamic lung compliance and blood pressure occurred after TMA challenge. In sensitized animals, the same dose of TMA caused significantly greater effects compared to non-sensitized animals. In a separate experiment, cellular infiltration into the lung was determined 24 h after challenge with TMA dust or lactose dust. In both non-sensitized and sensitized animals, eosinophils in the lung tissue were increased after TMA dust challenge compared to controls. Thus, these studies suggest that the response in non-sensitized animals differs depending on whether TMA dust or TMA-GPSA is used to elicit the response. TMA dust elicits significant airway obstruction and eosinophilia in a non-sensitized animal, with even

  15. Modified cyanobacteria

    Science.gov (United States)

    Vermaas, Willem F J.

    2014-06-17

    Disclosed is a modified photoautotrophic bacterium comprising genes of interest that are modified in terms of their expression and/or coding region sequence, wherein modification of the genes of interest increases production of a desired product in the bacterium relative to the amount of the desired product production in a photoautotrophic bacterium that is not modified with respect to the genes of interest.

  16. Computer-Aided Design and Computer-Aided Manufacturing Hydroxyapatite/Epoxide Acrylate Maleic Compound Construction for Craniomaxillofacial Bone Defects.

    Science.gov (United States)

    Zhang, Lei; Shen, Shunyao; Yu, Hongbo; Shen, Steve Guofang; Wang, Xudong

    2015-07-01

    The aim of this study was to investigate the use of computer-aided design and computer-aided manufacturing hydroxyapatite (HA)/epoxide acrylate maleic (EAM) compound construction artificial implants for craniomaxillofacial bone defects. Computed tomography, computer-aided design/computer-aided manufacturing and three-dimensional reconstruction, as well as rapid prototyping were performed in 12 patients between 2008 and 2013. The customized HA/EAM compound artificial implants were manufactured through selective laser sintering using a rapid prototyping machine into the exact geometric shapes of the defect. The HA/EAM compound artificial implants were then implanted during surgical reconstruction. Color-coded superimpositions demonstrated the discrepancy between the virtual plan and achieved results using Geomagic Studio. As a result, the HA/EAM compound artificial bone implants were perfectly matched with the facial areas that needed reconstruction. The postoperative aesthetic and functional results were satisfactory. The color-coded superimpositions demonstrated good consistency between the virtual plan and achieved results. The three-dimensional maximum deviation is 2.12 ± 0.65  mm and the three-dimensional mean deviation is 0.27 ± 0.07  mm. No facial nerve weakness or pain was observed at the follow-up examinations. Only 1 implant had to be removed 2 months after the surgery owing to severe local infection. No other complication was noted during the follow-up period. In conclusion, computer-aided, individually fabricated HA/EAM compound construction artificial implant was a good craniomaxillofacial surgical technique that yielded improved aesthetic results and functional recovery after reconstruction.

  17. Tuning the size of styrene-maleic acid copolymer-lipid nanoparticles (SMALPs) using RAFT polymerization for biophysical studies.

    Science.gov (United States)

    Craig, Andrew F; Clark, Emily E; Sahu, Indra D; Zhang, Rongfu; Frantz, Nick D; Al-Abdul-Wahid, M Sameer; Dabney-Smith, Carole; Konkolewicz, Dominik; Lorigan, Gary A

    2016-11-01

    Characterization of membrane proteins is challenging due to the difficulty in mimicking the native lipid bilayer with properly folded and functional membrane proteins. Recently, styrene-maleic acid (StMA) copolymers have been shown to facilitate the formation of disc-like lipid bilayer mimetics that maintain the structural and dynamic integrity of membrane proteins. Here we report the controlled synthesis and characterization of StMA containing block copolymers. StMA polymers with different compositions and molecular weights were synthesized and characterized by size exclusion chromatography (SEC). These polymers act as macromolecular surfactants for 1-Palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC)/1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-(1'-rac-glycerol (POPG) lipids, forming disc like structures of the lipids with the polymer wrapping around the hydrophobic lipid edge. A combination of dynamic light scattering (DLS), solid-state nuclear magnetic resonance (SSNMR) spectroscopy, and transmission electron microscopy (TEM) was used to characterize the size of the nanoparticles created using these StMA polymers. At a weight ratio of 1.25:1 StMA to lipid, the nanoparticle size created is 28+1nm for a 2:1 ratio, 10+1nm for a 3:1 StMA ratio and 32+1nm for a 4:1 StMA ratio independent of the molecular weight of the polymer. Due to the polymer acting as a surfactant that forms disc like nanoparticles, we term these StMA based block copolymers "RAFT SMALPs". RAFT SMALPs show promise as a new membrane mimetic with different nanoscale sizes, which can be used for a wide variety of biophysical studies of membrane proteins. Copyright © 2016. Published by Elsevier B.V.

  18. Apical microleakage of different root canal sealers after use of maleic acid and EDTA as final irrigants

    Directory of Open Access Journals (Sweden)

    Özgür İlke ULUSOY

    2014-01-01

    Full Text Available This study aimed to compare the effects of ethylenediaminetetraacetic acid (EDTA and maleic acid (MA on the sealing ability of various root canal sealers. Eighty root canals were instrumented and irrigated with either EDTA or MA. They were divided into eight experimental groups and obturated as follows: Group 1: MA + Hybrid Root SEAL/gutta-percha. Group 2: EDTA + Hybrid Root SEAL/gutta-percha. Group 3: MA + iRoot SP/gutta-percha. Group 4: EDTA + iRoot SP/gutta-percha. Group 5: MA + EndoREZ/EndoREZ points. Group 6: EDTA + EndoREZ/EndoREZ points. Group 7: MA + AH Plus/gutta-percha. Group 8: EDTA + AH Plus/gutta-percha. Another ten roots were used as negative and positive controls. The microleakage of each sample was measured at 2-min intervals for 8 min using the fluid filtration method. Data were statistically analyzed with one-way ANOVA, post-hoc Tukey, and paired-samples t tests. The minimum microleakage values were obtained from the teeth obturated with AH Plus and EndoREZ selaers (p < 0.001. The samples with Hybrid Root SEAL showed the maximum leakage (p < 0.001. There were significant differences between the groups irrigated with MA or EDTA in terms of microleakage (p < 0.05. Use of MA resulted in higher microleakage values compared with those using EDTA. The type of final irrigation solution seems to influence the postobturation apical seal. Use of AH Plus and EndoREZ sealers showed better sealing ability compared with IRoot SP and Hybrid Root SEAL.

  19. Biocompatible photocrosslinked poly(ester anhydride) based on functionalized poly(epsilon-caprolactone) prepolymer shows surface erosion controlled drug release in vitro and in vivo.

    Science.gov (United States)

    Mönkäre, J; Hakala, R A; Vlasova, M A; Huotari, A; Kilpeläinen, M; Kiviniemi, A; Meretoja, V; Herzig, K H; Korhonen, H; Seppälä, J V; Järvinen, K

    2010-09-15

    Star-shaped poly(epsilon-caprolactone) oligomers functionalized with succinic anhydride were used as prepolymers to prepare photocrosslinked poly(ester anhydride) to evaluate their in vivo drug delivery functionality and biocompatibility. Thus, in this work, erosion, drug release and safety of the photocrosslinked poly(ester anhydride) were examined in vitro and in vivo. A small water-soluble drug, propranolol HCl (M(w) 296 g/mol, solubility 50 mg/ml), was used as the model drug in an evaluation of the erosion controlled release. Drug-free and drug-loaded (10-60% w/w) poly(ester anhydride) discoids eroded in vitro (pH 7.4 buffer, +37 degrees C) linearly within 24-48 h. A strong correlation between the polymer erosion and the linear drug release in vitro was observed, indicating that the release had been controlled by the erosion of the polymer. Similarly, in vivo studies (s.c. implantation of discoids in rats) indicated that surface erosion controlled drug release from the discoids (drug loading 40% w/w). Oligomers did not decrease cell viability in vitro and the implanted discoids (s.c., rats) did not evoke any cytokine activity in vivo. In summary, surface erosion controlled drug release and the safety of photocrosslinked poly(ester anhydride) were demonstrated in this study.

  20. An Examination of the Chemistry of Peroxycarboxylic Nitric Anhydrides and Related Volatile Organic Compounds During Texas Air Quality Study 2000 Using Ground-Based Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, James M.; Jobson, B Tom T.; Kuster, W. C.; Goldan, P. D.; Murphy, Paul; Williams, Eric; Frost, G. J.; Riemer, D.; Apel, Eric; Stroud, C.; Wiedinmyer, Christine; Fehsenfeld, Fred C.

    2003-08-19

    Measurements of peroxycarboxylic nitric anhydrides (PANs) along with related volatile organic compounds (VOCs) were made at the La Porte super site during the TexAQS 2000 Houston study. The PAN mixing ratios ranged up to 6.5 ppbv and were broadly correlated with O3, characteristic of a highly polluted urban environment. The anthropogenic PAN homologue concentrations were generally consistent with those found in other urban environments; peroxypropionic nitric anhydride (PPN) averaged 15%, and peroxyisobutyric nitric anhydride (PiBN) averaged 3% of PAN,. Some periods were noted where local petrochemical sources resulted in anomalous PANs chemistry. This effect was especially noticeable in the case of peroxyacrylic nitric anhydride (APAN) where local sources of 1,3-butadiene and acrolein resulted in APAN as high as 30% of PAN. Peroxymethacrylic nitric anhydride (MPAN) was a fairly minor constituent of the PANs except for two periods on 4 and 5 September when air masses from high biogenic hydrocarbons (BHC) areas were observed. BHC chemistry was not a factor in the highest ozone pollution episodes in Houston but may have an impact on daily average ozone levels in some circumstances.

  1. Enhancement of mechanical properties, microstructure, and antimicrobial activities of zein films cross-linked using succinic anhydride, eugenol, and citric Acid.

    Science.gov (United States)

    Khalil, Ashraf A; Deraz, Sahar F; Elrahman, Somia Abd; El-Fawal, Gomaa

    2015-08-18

    Zein constitutes about half of the endosperm proteins in corn. Recently, attempts have been made to utilize zein for food coatings and biodegradable materials, which require better physical properties, using chemical modification of zein. In this study, zein proteins were modified using citric acid, succinic anhydride, and eugenol as natural cross-linking agents in the wet state. The cross-linkers were added either separately or combined in increment concentrations (0.1, 0.2, 0.3, and 0.4%). The effects of those agents on the mechanical properties, microstructure, optical properties, infrared (IR) spectroscopy, and antibacterial activities of zein were investigated. The addition of cross-linking agents promoted changes in the arrangement of groups in zein film-forming particles. Regarding the film properties, incorporation of cross-linking agents into zein films prepared in ethanol resulted in two- to three-fold increases in tensile strength (TS) values. According to the Fourier-transform infrared (FTIR) spectra and Hunter parameters there were no remarkable changes in the structure and color of zein films. Transparency of zein films was decreased differentially according to the type and cross-linker concentration. The mechanical and optical properties of zein films were closely related to their microstructure. All cross-linked films showed remarkable antibacterial activities against Bacillus cereus ATCC 49064 and Salmonella enterica ATCC 25566. Food spoilage and pathogenic bacteria were affected in a film-dependent manner. Our experimental results show that even with partial cross-linking the mechanical properties and antipathogen activities of zein films were significantly improved, which would be useful for various industrial applications.

  2. Converting non-metallic printed circuit boards waste into a value added product

    OpenAIRE

    Shantha Kumari Muniyandi; Johan Sohaili; Azman Hassan; Siti Suhaila Mohamad

    2013-01-01

    The aim of this study was to investigate the feasibility of using nonmetallic printed circuit board (PCB) waste as filler in recycled HDPE (rHDPE) in production of rHDPE/PCB composites. Maleic anhydride modified linear low-density polyethylene (MAPE) was used as compatibilizer. In particular, the effects of nonmetallic PCB and MAPE on mechanical properties of the composites were assessed through tensile, flexural and impact testing. Scanning electron microscope (SEM) was used to study the dis...

  3. A new fabrication route for PVA/graphene platelets composites with enhanced functionalities

    Science.gov (United States)

    Lavecchia, Teresa; Tamburri, Emanuela; Angjellari, Mariglen; Savi, Damiano; Terranova, Maria Letizia

    2016-05-01

    This work deals with the synthesis and characterization of composites made of poly(vinyl alcohol) (PVA) and oxidized graphene platelets obtained from an ad hoc treatment of graphite. The composite is produced by a modified solution mixing procedure in which the in situ crosslinking of PVA with maleic anhydride has been carried out in the presence of the carbon filler. A complete characterization of the material is presented carried out by SEM, DTGA, Raman spectroscopy and I-V characteristics analysis.

  4. Polyethylene Maleate Copolyesters as Coating Materials for Piezoelectric Quartz Crystal-based Chemical Sensors

    OpenAIRE

    D. C. Gupta; C. Saxena; V. Dubey; P. K. Gutch; R. Asrey; K. D. Vyas

    2005-01-01

    Polyethylene maleate (PEM) was synthesised by direct polycondensation of maleic anhydride and ethylene glycol in toluene under reflux usingp-toluene sulphonic acid as a catalyst. Structure of PEM was further modified by varying nature of diols and acid components, chain length of glycols, incorporation of aromatic and fluorine groups in the chain. Formation of PEM was monitored by gas chromatography. The parameters like degree of polymerisation, number average molecular weight (Mn), and weigh...

  5. Continuous Preparation of 1:1 Haloperidol-Maleic Acid Salt by a Novel Solvent-Free Method Using a Twin Screw Melt Extruder.

    Science.gov (United States)

    Lee, Hung Lin; Vasoya, Jaydip M; Cirqueira, Marilia de Lima; Yeh, Kuan Lin; Lee, Tu; Serajuddin, Abu T M

    2017-03-10

    Salts are generally prepared by acid-base reaction in relatively large volumes of organic solvents, followed by crystallization. In this study, the potential for preparing a pharmaceutical salt between haloperidol and maleic acid by a novel solvent-free method using a twin-screw melt extruder was investigated. The pH-solubility relationship between haloperidol and maleic acid in aqueous medium was first determined, which demonstrated that 1:1 salt formation between them was feasible (pHmax 4.8; salt solubility 4.7 mg/mL). Extrusion of a 1:1 mixture of haloperidol and maleic acid at the extruder barrel temperature of 60 °C resulted in the formation of a highly crystalline salt. The effects of operating temperature and screw configuration on salt formation were also investigated, and those two were identified as key processing parameters. Salts were also prepared by solution crystallization from ethyl acetate, liquid-assisted grinding, and heat-assisted grinding and compared with those obtained by melt extrusion by using DSC, PXRD, TGA, and optical microscopy. While similar salts were obtained by all methods, both melt extrusion and solution crystallization yielded highly crystalline materials with identical enthalpies of melting. During the pH-solubility study, a salt hydrate form was also identified, which, upon heating, converted to anhydrate similar to that obtained by other methods. There were previous reports of the formation of cocrystals, but not salts, by melt extrusion. (1)H NMR and single-crystal X-ray diffraction confirmed that a salt was indeed formed in the present study. The haloperidol-maleic acid salt obtained was nonhygroscopic in the moisture sorption study and converted to the hydrate form only upon mixing with water. Thus, we are reporting for the first time a relatively simple and solvent-free twin-screw melt extrusion method for the preparation of a pharmaceutical salt that provides material comparable to that obtained by solution

  6. PREPARATION OF ISOMERIZED METHYL TETRAHYDROPHTHALIC ANHYDRIDE%异构化甲基四氢苯酐的研制

    Institute of Scientific and Technical Information of China (English)

    吴光杰

    2001-01-01

    Isomerized methyl tetrahydrophthalic anhydride with low viscosity,a curing agent of epoxy resin (N-570D),was prepared in this paper.Effect of some factors,such as catalyst,temperature et al on product gield and method of inhibitting side reaction were also discussed.%制备了低粘度环氧树脂固化剂(N-570D),即:异构化甲基四氢苯酐(MeTHPA),讨论催化剂等因素对收率的影响,并论述了抑制副反应的方法。

  7. KINETIC STUDY OF CARBONYLATION OF METHANOL TO ACETIC ACID AND ACETIC ANHYDRIDE OVER A NOVEL COPOLYMER- BOUND CIS- DICARBONYLRHODIUM COMPLEX

    Institute of Scientific and Technical Information of China (English)

    CHEN Yuying; YUAN Guoqing; CHEN Rongyao

    1989-01-01

    The kinetic study of carbonylation of methanol-acetic acid mixture to acetic acid and acetic anhydride over a cis-dicarbonylrhodium complex (MVM' Rh)coordinated with the ethylene diacrylate (M')crosslinked copolymer of methyl acrylate (M) and 2 - vinylpyridine (V) shows that the rate of reaction is zero order with respect to both reactants methanol and carbon monoxide, but first order in the concentrations of promoter methyl iodide and rhodium in the complex . Polar solvents can accelerate the reaction .Activation parameters were calculated from the experimental results, being comparable to that of the homogeneous system . A mechanism similar to that of soluble rhodium catalyst was proposed .

  8. Synthesis and characterization of hyperbranched poly(glycidol) modified with pH- and temperature-sensitive groups.

    Science.gov (United States)

    Kojima, Chie; Yoshimura, Kohei; Harada, Atsushi; Sakanishi, Yuichi; Kono, Kenji

    2009-05-20

    Hyperbranched poly(glycidol)s with varying degrees of polymerization were modified by reaction with succinic anhydride and isopropylamine to obtain novel pH- and thermosensitive polymers. These polymers exhibited phase transitions in response to decreasing pH and/or increasing temperature, depending on the degree of polymerization and the ratio of succinyl group to N-isopropylamide. It was possible to harvest a bioactive molecule, rose bengal, from solution using the phase transition of thermosensitive hyperbranched poly(glycidol).

  9. Investigation of the ageing effects on phenol-urea-formaldehyde binder and alkanol amine-acid anhydride binder coated mineral fibres

    DEFF Research Database (Denmark)

    Zafar, Ashar; Schjødt-Thomsen, Jan; Sodhi, R.;

    2013-01-01

    Phenol-Urea-Formaldehyde (PUF) binder coated mineral fibres' mechanical properties have been observed to degrade during ageing at elevated temperatures and humidity, while alkanol amine-acid anhydride binder based mineral fibres exhibited better ageing properties for same duration of ageing. X......-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS) were employed to identify the chemical changes occurring in the PUF binder coated mineral fibres and alkanol amine-acid anhydride binder coated mineral fibres during that ageing. The samples were aged in a climate...... of amide, methylene ether and methylene linkages between urea groups present in the PUF binder. In the case of the alkanol amine-acid anhydride binder coated mineral fibres, both XPS and ToF-SIMS techniques consistently showed that the surface chemical composition of the organic components of the alkanol...

  10. 琥珀酸酐生产新工艺探讨%The Study of New Technology of Producing Amber Anhydride

    Institute of Scientific and Technical Information of China (English)

    吕杨

    2012-01-01

    It introduced the properties of Amber Anhydride and widely used in every field.Introducing the major technology of producing Amber Anhydride.Reviewing new tecnology of producing Amber Anhydride and comparing the major technology with new technology to explaining the superiority of new technology.%介绍了琥珀酸酐的性质及在各个领域的广泛用途,介绍了目前国内琥珀酸酐的主要生产工艺技术方案,综述了琥珀酸酐生产新技术,并对目前国内琥珀酸酐的主要生产工艺和琥珀酸酐生产新工艺进行了比较,突出了新工艺的优势。

  11. Synthesis of comb-like copolymers from renewable resources: Itaconic anhydride, stearyl methacrylate and lactic acid

    Science.gov (United States)

    Shang, Shurui

    The synthesis and properties of comb-like copolymers and ionomers derived from renewable resources: itaconic anhydride (ITA), stearyl methacrylate (SM) and lactic acid (LA) are described. The copolymers based on ITA and SM (ITA-SM) were nearly random with a slight alternating tendency. The copolymers exhibited a nanophase-separated morphology, with the stearate side-chains forming a bilayer, semi-crystalline structure. The crystalline side-chains suppressed molecular motion of the main-chain, so that a glass transition temperature (Tg) was not resolved unless the ITA concentration was sufficiently high so that Tg > the melting point (Tm). The softening point and modulus of the copolymers increased with the increasing ITA concentration, but the thermal stability decreased. The ITA moiety along the main chain of the copolymers was neutralized with metal acetates to produce Na-, Ca- and Zn- random ionomers with comb-like architectures. In general, the incorporation of the ionic groups increased the Tg and suppressed the crystallinity of the side-chain packing. Ionomers with high SM side-chain density had two competing driving forces for self-assembled nano-phase separation: ionic aggregation and side-chain crystalline packing. Upon neutralization, a morphological transition from semi-crystalline lamella to spherical ionic aggregation was observed by small angle X-ray scattering (SAXS) analysis and transmission electron microscopy (TEM). Thermomechanical analysis revealed an increasing resistance to penetration deformation with an increasing degree of neutralization and an apparent rubbery plateau was observed above Tg. A controlled transesterification of PLA in glassware was an effective way to prepare a methacrylate functionalized PLA macromonomer with controlled molecular weight, which was used to synthesize a variety of copolymers. The copolymerization of this functionalized PLA macromonomer with ITA totally suppressed the side-chain crystallinity for the PLA chain

  12. Increased oral bioavailability of paclitaxel by its encapsulation through complex formation with cyclodextrins in poly(anhydride) nanoparticles.

    Science.gov (United States)

    Agüeros, M; Zabaleta, V; Espuelas, S; Campanero, M A; Irache, J M

    2010-07-01

    The aim of this work was to study the oral bioavailability in rats of paclitaxel (PTX) when encapsulated as a complex with cyclodextrins in poly(anhydride) nanoparticles (NP). For this purpose three different cyclodextrins were selected: beta-cyclodextrin (CD), 2-hydroxypropyl-beta-cyclodextrin (HPCD) and 6-monodeoxy-6-monoamino-beta-cyclodextrin (NHCD). A single dose of 10mg paclitaxel per kg body weight as PTX-cyclodextrin nanoparticles was used. Plasma curves were characterised by a plateau of paclitaxel concentration close to the C(max) from T(max) till 24h post-administration. For PTX-CD NP and PTX-HPCD NP, these sustained levels of the anticancer drug were found to be between 27 and 33-fold higher than the reported value of drug activity whereas the relative oral bioavailability of paclitaxel was calculated to be higher than 80%. These facts would be directly related with a synergistic effect obtained by the combination of the bioadhesive properties of poly(anhydride) nanoparticles and the inhibitory effect of cyclodextrins on the activity of P-glycoprotein and cythocrome P450.

  13. Synthesis and characterization of poly(maleic acid)-grafted crosslinked chitosan nanomaterial with high uptake and selectivity for Hg(II) sorption.

    Science.gov (United States)

    Ge, Huacai; Hua, Tingting

    2016-11-20

    Chitosan-poly(maleic acid) nanomaterial (PMACS) with the size of 400-900nm was synthesized by grafting poly(maleic acid) onto chitosan and then crosslinking with glutaraldehyde. The synthesis conditions were optimized. The structure and morphology of PMACS were characterized by FT-IR, XRD, SEM and TGA. PMACS was used to adsorb some heavy metal ions such as Hg(II), Pb(II), Cu(II), Cd(II), Co(II), and Zn(II). The results indicated that PMACS had selectivity for Hg(II) sorption. The effects of various variables for sorption of Hg(II) were further explored. The maximum capacity for Hg(II) sorption was found to be 1044mgg(-1) at pH 6.0, which could compare with the maximal value of the recently reported other sorbents. The sorption followed the pseudo-second-order kinetics and Langmuir isotherm models. The rising of temperature benefited the uptake and the sorption was a spontaneous chemical process. The sorbent could be reused with EDTA. Hence, the nanomaterial would be used as a selective and high uptake sorbent in the removal of Hg(II) from effluents. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. High Dielectric Performance of Polyamide 66/Poly(Vinylidene Fluoride Flexible Blends Induced by Interfacial Copolymer for Capacitors

    Directory of Open Access Journals (Sweden)

    Rui Li

    2015-12-01

    Full Text Available The copolymer VAMA was synthesized from vinyl acetic and maleic anhydride. A new all-polymeric blend with a high dielectric constant (ε has been developed by blending polyvinylidene fluoride (PVDF with vinyl acetic-maleic anhydride modified polyamide (PA66-g-VM. The blend shows high dielectric constants (εblend = 20 and excellent mechanical properties. The SEM investigations suggest that the enhanced dielectric behavior originates from significant interfacial interactions between polymers. The XRD demonstrates that the compatibilizer affects the crystalline behavior of each component. Furthermore, the stable dielectric constants of the all-polymeric blends can be tuned by adjusting the content of the compatibilizer. The created high-ε all-polymeric blends represent a novel type of material that is technologically simple, easy to process, and of a relatively high dielectric constant, with application for flexible electronics.

  15. A Linear Relationship between the Mechanical, Thermal and Gas Barrier Properties of MAPE Modified Rubber Toughened Nanocomposites

    Directory of Open Access Journals (Sweden)

    Nur Ayuni jamal

    2010-11-01

    Full Text Available Composites based on high density polyethylene (HDPE, ethylene propylene diene monomer (EPDM and organophilic montmorillonite (OMMT clays were prepared by melt compounding followed by compression molding. The addition of clay as well as compatibilizer agent (maleic anhydride polyethylene (MAPE considerably improved the tensile properties of nanocomposites systems. The largest improvement in mechanical and thermal properties occurred at clay loading levels of 4% (2-8 wt % with MAPE system. Interestingly, the increased in tensile properties also resulted in improve in thermal and barrier properties. Differential scanning calorimeter analysis (DSC revealed that the barrier property of nanocomposite was influenced by the crystalline percentage of nanocomposite. Along with crystalline percentage, the crystallization temperature, Tc and melting temperature, Tm were also improved with OMMT and MAPE agent. The d-spacings of the clay in nanocomposites were monitored using x-ray diffraction (XRD and the extent of delamination was examined by transmission electron microscope (TEM. The wide angle of XRD patterns showed the increased interplanar spacing, d of clay layers, indicating enhanced compatibility between polymer matrix and OMMT with the aid of MAPE agent. TEM photomicrographs illustrated the mixed intercalated and partial exfoliated structures of the nanocomposites with OMMT and MAPE agent.

  16. Influence of modified polyester on the material properties of collagen-based biocomposites and in vitro evaluation of cytocompatibility

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Chin-San, E-mail: t50008@cc.kyu.edu.tw

    2015-03-01

    The cytocompatibility of composite materials collagen (Col)/poly(hydroxyalkanoate) (PHA) and collagen/maleic anhydride-grafted PHA (PHA-g-MA) was investigated in this study. Col was homogeneously dispersed in the PHA-g-MA matrix as a result of condensation reactions. Mechanical characterisation indicated that the improved adhesion between Col and PHA-g-MA enhanced the tensile strength of the composite compared with that of PHA/Col. PHA-g-MA/Col composites were also more water-resistant than PHA/Col composites. Collagen and cell proliferation analysis indicated that PHA and PHA-g-MA and their composites were biocompatible with respect to FB proliferation. Cell-cycle and apoptosis assays by FBs on the PHA series composite samples were not affected by DNA content related to damage, i.e. rapid apoptosis/necrosis was not observed, demonstrating the potential of PHA/Col or PHA-g-MA/Col membranes for biomedical material applications. - Highlights: • Composites were prepared using polyester and collagen to explore their cytocompatibility. • The mechanical properties of the composite were significantly enhanced by the use of grafted polyester and collagen. • The polyester and collagen composites facilitated excellent cell viability and collagen production. • The cell cycle was not affected by DNA content related to damage, and it did not lead to rapid apoptosis or necrosis of the cells by the composite.

  17. Influence of modified polyester on the material properties of collagen-based biocomposites and in vitro evaluation of cytocompatibility.

    Science.gov (United States)

    Wu, Chin-San

    2015-03-01

    The cytocompatibility of composite materials collagen (Col)/poly(hydroxyalkanoate) (PHA) and collagen/maleic anhydride-grafted PHA (PHA-g-MA) was investigated in this study. Col was homogeneously dispersed in the PHA-g-MA matrix as a result of condensation reactions. Mechanical characterisation indicated that the improved adhesion between Col and PHA-g-MA enhanced the tensile strength of the composite compared with that of PHA/Col. PHA-g-MA/Col composites were also more water-resistant than PHA/Col composites. Collagen and cell proliferation analysis indicated that PHA and PHA-g-MA and their composites were biocompatible with respect to FB proliferation. Cell-cycle and apoptosis assays by FBs on the PHA series composite samples were not affected by DNA content related to damage, i.e. rapid apoptosis/necrosis was not observed, demonstrating the potential of PHA/Col or PHA-g-MA/Col membranes for biomedical material applications.

  18. Effect of organic additives on mechanical properties of SiC ceramics prepared by a modified gelcasting method

    Directory of Open Access Journals (Sweden)

    Feng Wang

    2016-12-01

    Full Text Available A novel and simple gel system of isobutylene and maleic anhydride (PIBM was used to prepare SiC ceramics. The rheological behaviour of the SiC slurries was investigated as function of organic additives. The SiC slurries with 0.2 wt.% PIBM and 0.2 wt.% tetramethylammonium hydroxide (TMAH showed low viscosity, which was favourable for casting SiC green bodies. In order to obtain homogeneous green bodies, polyvinyl alcohol (PVA was used to assist the dispersion of carbon black in the slurries, and polyethylene glycol (PEG was added to inhibit the surface exfoliation of green bodies. The content of PVA was controlled carefully to avoid the warpage of green bodies during the drying process. Finally, homogeneous defect-free SiC green bodies were successfully fabricated via aqueous gelcasting. The SiC ceramics sintered at 2100 °C (prepared from slurries with solid content of 60 wt.% showed an average flexural strength of 305.7 MPa with porosity of 19.92%.

  19. Greener Friedel-Crafts Acylation using Microwave-enhanced reactivity of Bismuth Triflate in the Friedel-Crafts Benzoylation of Aromatic Compounds with Benzoic Anhydride

    DEFF Research Database (Denmark)

    Tran, Phuong Hoang; Nguyen, hai Truong; Hansen, Poul Erik

    2017-01-01

    An efficient and facile bismuth trifluoromethanesulfonate-catalyzed benzoylation of aromatic compounds using benzoic anhydride under solvent-free microwave irradiation has been developed. The microwave-assisted Friedel-Crafts benzoylation results in good yields within short reaction times. Bismut...

  20. 40 CFR 721.3635 - Octadecanoic acid, ester with 1,2-propanediol, phosphate, anhydride with silicic acid (H4SiO4).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Octadecanoic acid, ester with 1,2..., ester with 1,2-propanediol, phosphate, anhydride with silicic acid (H4SiO4). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as octadecanoic acid,...

  1. An atom-economic approach to carboxylic acids via Pd-catalyzed direct addition of formic acid to olefins with acetic anhydride as a co-catalyst.

    Science.gov (United States)

    Wang, Yang; Ren, Wenlong; Shi, Yian

    2015-08-21

    An effective Pd-catalyzed hydrocarboxylation of olefins using formic acid with acetic anhydride as a co-catalyst is described. A variety of carboxylic acids are obtained in good yields with high regioselectivities under mild reaction conditions without the use of toxic CO gas.

  2. Chitosan: poly(N-vinylpyrrolidone-alt-itaconic anhydride) nanocapsules—a promising alternative for the lung cancer treatment

    Energy Technology Data Exchange (ETDEWEB)

    Raţă, Delia Mihaela, E-mail: iureadeliamihaela@yahoo.com [„Apollonia” University of Iasi, Faculty of Medical Dentistry, „Academician Ioan Haulică” Research Institute (Romania); Chailan, Jean-François, E-mail: chailan@univ-tln.fr [University of Sud Toulon-Var, « Matériaux-Polymères-Interfaces-Environnement Marin (MAPIEM) Laboratory (France); Peptu, Cătălina Anişoara, E-mail: catipeptu@yahoo.co.uk [“Gheorghe Asachi” Technical University of Iasi, Department of Natural and Synthetic Polymers, Faculty of Chemical Engineering and Environmental Protection (Romania); Costuleanu, Marcel, E-mail: mcostuleanu@yahoo.com [University of Medicine and Pharmacy “Grigore T. Popa”- Iaşi, Department of General Pathology, Faculty of Dental Medicine (Romania); Popa, Marcel, E-mail: marpopa2001@yahoo.fr [“Gheorghe Asachi” Technical University of Iasi, Department of Natural and Synthetic Polymers, Faculty of Chemical Engineering and Environmental Protection (Romania)

    2015-07-15

    This study reports the preparation of novel polymeric nanocapsules based on a natural polymer, chitosan and a synthetic one, poly(N-vinylpyrrolidone-alt-itaconic anhydride) [(poly(NVPAI)] using an interfacial condensation technique. The infrared spectroscopy studies confirmed the crosslinking through the presence of amide bonds, formed between the two polymers chains. The diameter of nanocapsules was found in the range of 126–214 nm and it was determined by dynamic light scattering method. Morphological characterization demonstrated their nano size, the spherical shape of the nanocapsules and the formation of hollow particles. The nanocapsules presented good swelling capacity in aqueous solutions. 5-Fluorouracil (5-FU) loading and release capacity was studied, the processes being controlled by the drug diffusion through the polymeric membrane. The obtained results were encouraging, showing that 5-FU-loaded nanocapsules had 70 % higher apoptotic effect on A549 tumour cells than the drug in free state or mixed with the nanocapsules.

  3. Synthesis of 1H-benzoxazine-2,4-diones from heterocyclic anhydrides: evaluation of antioxidant and antimicrobial activities

    Directory of Open Access Journals (Sweden)

    Juan I. Sarmiento-Sánchez

    2014-01-01

    Full Text Available A facile one-step synthesis of 1H-benzoxazine-2,4-diones from heterocyclic anhydrides and TMSA was described. This paper determines their antimicrobial activity against nine human bacterial pathogens by the broth microdilution method; antioxidant activity by DPPH• inactivation and a ferric-reducing power assay; and toxicity by a brine shrimp, Artemia salina, assay. The 1H-benzoxazine-2,4-dione yields were in the range of 57 to 98%. The novel compound 1H-pyrazino[2,3-][1,3]oxazine-2,4-dione 4c showed the highest antioxidant capacity (DPPH 35.4% and FRAP 0.063 µmol TEs/µmol.

  4. Deactivation properties of a high-productive vanadia-titania catalyst for oxidation of o-xylene to phthalic anhydride

    Directory of Open Access Journals (Sweden)

    A. T. Georgieva

    2008-06-01

    Full Text Available The behavior of a high-productive V2O5-TiO2 (anatase supported O 4-28 catalyst for oxidation of o-xylene to phthalic anhydride was investigated in the first three years of its exploitation in industry. By using a suitable mathematical model, an identification problem was solved and activation profiles of the catalyst along a fixed bed located in the tubes of an industrial reactor were determined. Experimental temperature regimes and yields of the main and side products for different periods of the catalyst life were used. The proper technological regimes providing for a maximum yield according to the requirements of the catalyst producer company were defined.

  5. Chitosan: poly( N-vinylpyrrolidone- alt-itaconic anhydride) nanocapsules—a promising alternative for the lung cancer treatment

    Science.gov (United States)

    Raţă, Delia Mihaela; Chailan, Jean-François; Peptu, Cătălina Anişoara; Costuleanu, Marcel; Popa, Marcel

    2015-07-01

    This study reports the preparation of novel polymeric nanocapsules based on a natural polymer, chitosan and a synthetic one, poly( N-vinylpyrrolidone- alt-itaconic anhydride) [(poly(NVPAI)] using an interfacial condensation technique. The infrared spectroscopy studies confirmed the crosslinking through the presence of amide bonds, formed between the two polymers chains. The diameter of nanocapsules was found in the range of 126-214 nm and it was determined by dynamic light scattering method. Morphological characterization demonstrated their nano size, the spherical shape of the nanocapsules and the formation of hollow particles. The nanocapsules presented good swelling capacity in aqueous solutions. 5-Fluorouracil (5-FU) loading and release capacity was studied, the processes being controlled by the drug diffusion through the polymeric membrane. The obtained results were encouraging, showing that 5-FU-loaded nanocapsules had 70 % higher apoptotic effect on A549 tumour cells than the drug in free state or mixed with the nanocapsules.

  6. Facile Formation of Acetic Sulfuric Anhydride in a Supersonic Jet: Characterization by Microwave Spectroscopy and Computational Chemistry

    Science.gov (United States)

    Huff, Anna; Smith, CJ; Mackenzie, Becca; Leopold, Ken

    2017-06-01

    Sulfur trioxide and acetic acid are shown to react under supersonic jet conditions to form acetic sulfuric anhydride, CH_{3}COOSO_{2}OH. Rotational spectra of the parent, ^{34}S, methyl ^{13}C, and fully deuterated isotopologues have been observed by chirped-pulse and conventional cavity microwave spectroscopy. A and E internal rotation states have been observed for each isotopologue studied and the methyl group internal rotation barriers have been determined (241.043(65) \\wn for the parent species). The reaction is analogous to that of our previous report on the reaction of sulfur trioxide and formic acid. DFT and CCSD calculations are also presented which indicate that the reaction proceeds via a π_{2} + π_{2} + σ_{2} cycloaddition reaction. These results support our previous conjecture that the reaction of SO_{3} with carboxylic acids is both facile and general. Possible implications for atmospheric aerosol formation are discussed.

  7. Effect of succinic anhydride as an electrolyte additive on electrochemical characteristics of silicon thin-film electrode

    Science.gov (United States)

    Han, Gi-Beom; Ryou, Myung-Hyun; Cho, Kuk Young; Lee, Yong Min; Park, Jung-Ki

    The effect of an electrolyte additive, succinic anhydride (SA), on the electrochemical performances of a silicon thin-film electrode, which is prepared by radio-frequency magnetron sputtering, is investigated. The introduction of SA into a liquid electrolyte consisting of ethylene carbonate/diethyl carbonate/1 M LiPF 6 significantly enhances the capacity retention and coulombic efficiency of the electrode. This improvement in the electrochemical performance of the electrode is attributed to modification of the solid/electrolyte interphase (SEI) layer by the introduction of SA. The differences in the characteristic properties of SEI layers, with or without SA, are explained by analysis with scanning electron microscopy, electrochemical impedance spectroscopy, and X-ray photoelectron spectroscopy.

  8. Effect of wood acetylation with vinyl acetate and acetic anhydride on the properties of wood-plastic composites

    Directory of Open Access Journals (Sweden)

    Nilgül Özmen

    2013-02-01

    Full Text Available Chemical modifications of Scots pine (Pinus slyvestris wood flour were performed with vinyl acetate (VA and acetic anhydride (AA in the presence of potassium carbonate as a catalyst. Scots pine wood flour samples were successfully acetylated with VA (19 wt% gain and AA (24 wt% gain. The effect of chemical modification of the Scots pine wood flour with AA and VA on the mechanical properties of wood high-density polyethylene composites (WPC were determined. It was observed that acetylation of wood flour allowed a significant increase in both the mechanical properties and the thermal stability of the WPCs. It was concluded that acetylation of lignocellulosic fibers improves thermal stability, dispersion in the polymer matrix, and compatibility with the polymer matrix.

  9. Changes in asthma-like responses after extended removal from exposure to trimellitic anhydride in the Brown Norway rat model.

    Science.gov (United States)

    Zhang, X D; Hubbs, A F; Siegel, P D

    2009-11-01

    Organic acid anhydride-induced occupational asthma is considered to be IgE-mediated. Airway and skin exposure are the two main routes of sensitization in the work place. Recently we developed an allergic asthmatic Brown Norway rat model sensitized by dermal exposure to trimellitic anhydride (TMA) using an occlusion patch application. The objectives of this study were (1) to develop a model of non-occluded dermal exposure leading to allergic sensitization and (2) to examine the effect of extended removal from exposure on persistence of both specific IgE and TMA aerosol-induced airway responses in this model. TMA powder (4 or 40 mg) was applied, unoccluded, to the skin of rats for 4 h, once/week for 4 weeks. Rats were given a 10-min aerosol challenge to 40 mg/m(3) TMA 2 weeks after the last dermal exposure (day 35). Another group was challenged on day 35 and again 18-24 months later. Respiratory enhanced pause (Penh), pulmonary histopathology and inflammation and specific IgE titres were measured. Rats produced dose-dependent specific IgE titres after exposure and developed early-phase (EAR) and late-phase airway responses (LAR) after airway challenge to TMA aerosol as well as airway eosinophilic inflammation. Specific airway responses were still manifested after a second TMA airway challenge given 18-24 months following the initial airway challenge. While persistent, airway inflammation, specific IgE and EAR were significantly attenuated following the second TMA challenge. LAR remained robust at 18-24 months and was not significantly different from the response on day 35. These results demonstrate the persistence of chemical sensitization and further suggest that IgE is not essential for LAR.

  10. Rapid microwaves synthesis of CoSi{sub x}/CNTs as novel catalytic materials for hydrogenation of phthalic anhydride

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Liangliang [School of Engineering and Technology, China University of Geosciences, Beijing 100083 (China); Chen, Xiao; Jin, Shaohua; Guan, Jingchao [Laboratory of Advanced Materials and Catalytic Engineering, Dalian University of Technology, Dalian 116024 (China); Williams, Christopher T. [Department of Chemical Engineering, University of South Carolina, Columbia, SC 29208 (United States); Peng, Zhijian, E-mail: pengzhijian@cugb.edu.cn [School of Engineering and Technology, China University of Geosciences, Beijing 100083 (China); Liang, Changhai, E-mail: changhai@dlut.edu.cn [Laboratory of Advanced Materials and Catalytic Engineering, Dalian University of Technology, Dalian 116024 (China)

    2014-09-15

    CoSi{sub x}/CNTs catalysts with different CoSi{sub x} phases (CoSi, CoSi{sub 2}) have been rapidly synthesized via a microwave-assisted route and applied for the liquid phase hydrogenation of phthalic anhydride. The synthesized catalysts were analyzed and characterized by X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy-energy dispersive X-ray spectroscopy, thermogravimetric/derivative thermogravimetric analysis. The reaction progress of cobalt silicides and the ratio of Co:Si were monitored at different microwave irradiation times by XRD, giving insight into the formation mechanism. Compared to the Co/CNTs catalyst, all the prepared CoSi{sub x}/CNTs catalysts exhibited excellent activity and good selectivity to phthalide under mild reaction conditions (180–220 °C and 4.0 MPa H{sub 2}). This novel methodology can be applied to the synthesis of other transition metal silicides such as FeSi, Ni{sub 2}Si, and Cu{sub 4}Si. - Graphical abstract: CoSi{sub x}/CNTs catalysts with different CoSi{sub x} phases (CoSi{sub 2}, CoSi) have been rapidly synthesized via microwave-assisted route, which involves the vaporization of CoCl{sub 2} and subsequent reaction of CoCl{sub 2} with Si. - Highlights: • CoSi{sub x}/CNTs catalysts have been rapid synthesized via microwave-assisted route. • The phases of CoSi{sub x} were controlled by varying microwave time and Co:Si ratio. • FeSi, Ni{sub 2}Si and Cu{sub 4}Si were also synthesized via microwave-assisted route. • CoSi{sub x}/CNTs catalysts can be applied in hydrogenation of phthalic anhydride.

  11. Effect of water absorption on mechanical properties of flax fibre reinforced composites

    CSIR Research Space (South Africa)

    Guduri, BBR

    2007-01-01

    Full Text Available flax fibre composites were prepared by compounding, extrusion and injection moulding techniques. Polypropylene-graft-Maleic anhydride (PP-g-MA, Grade: G-3015) and Polyethylene-graft-Maleic anhydride (PE-g-MA, Grade: G-2608) were used as compatibilizer...

  12. Photocurable bioactive bone cement based on hydroxyethyl methacrylate-poly(acrylic/maleic) acid resin and mesoporous sol gel-derived bioactive glass

    Energy Technology Data Exchange (ETDEWEB)

    Hesaraki, S., E-mail: S-hesaraki@merc.ac.ir

    2016-06-01

    This paper reports on strong and bioactive bone cement based on ternary bioactive SiO{sub 2}-CaO-P{sub 2}O{sub 5} glass particles and a photocurable resin comprising hydroxyethyl methacrylate (HEMA) and poly(acrylic/maleic) acid. The as-cured composite represented a compressive strength of about 95 MPa but it weakened during soaking in simulated body fluid, SBF, qua its compressive strength reached to about 20 MPa after immersing for 30 days. Biodegradability of the composite was confirmed by reducing its initial weight (~ 32%) as well as decreasing the molecular weight of early cured resin during the soaking procedure. The composite exhibited in vitro calcium phosphate precipitation in the form of nanosized carbonated hydroxyapatite, which indicates its bone bonding ability. Proliferation of calvarium-derived newborn rat osteoblasts seeded on top of the composite was observed during incubation at 37 °C, meanwhile, an adequate cell supporting ability was found. Consequently, it seems that the produced composite is an appropriate alternative for bone defect injuries, because of its good cell responses, high compressive strength and ongoing biodegradability, though more in vivo experiments are essential to confirm this assumption. - Highlights: • Light cure cement based on SiO{sub 2}-CaO-P{sub 2}O{sub 5} glass and polymer-like matrix was formed. • The matrix includes poly(acrylic/maleic acid) and poly(hydroxyethyl methacrylate). • The cement is as strong as polymethylmethacrylate bone cement. • The cement exhibits apatite formation ability in simulated body fluid. • The cement is biodegradable and supports proliferation of osteoblastic cells.

  13. Utilizing maleic acid as a novel fuel for synthesis of PbFe{sub 12}O{sub 19} nanoceramics via sol–gel auto-combustion route

    Energy Technology Data Exchange (ETDEWEB)

    Ansari, Fatemeh; Soofivand, Faezeh; Salavati-Niasari, Masoud, E-mail: salavati@kashanu.ac.ir

    2015-05-15

    PbFe{sub 12}O{sub 19} nanostructures were prepared in an aqueous solution by the sol–gel auto-combustion method using Pb(NO{sub 3}){sub 2} and Fe(NO{sub 3}){sub 3} as starting materials and various carboxylic acids, including oxalic acid, malonic acid, succinic acid and maleic acid as fuel and reducing and capping agents. The as-synthesized products were characterized by X- ray diffraction, scanning electron microscopy, and X-ray energy dispersive spectroscopy. The effect of carboxylic acid type, Pb{sup +} {sup 2} to carboxylic acid molar ratio, and calcination temperature was investigated on the morphology of the products and several experiments were carried out to obtain the optimal reaction conditions. It was found that the phase and the morphology of the products are influenced by the investigated parameters. Furthermore, vibrating sample magnetometer (VSM) was used to study the magnetic properties of PbFe{sub 12}O{sub 19} samples. - Graphical abstract: Display Omitted - Highlights: • PbFe{sub 12}O{sub 19} nanoceramics were synthesized from Fe(NO{sub 3}){sub 3} and Pb(NO{sub 3}){sub 2} via the sol–gel auto combustion method. • The maleic acid can be instead of common capping agent and fuel in auto-combustion sol–gel. • The synthesized PbFe{sub 12}O{sub 19} is a hard magnetic material. • The specific saturation magnetization and coercivity are 27 emu/g and 1900 Oe, respectively.

  14. The effectiveness of styrene-maleic acid (SMA) copolymers for solubilisation of integral membrane proteins from SMA-accessible and SMA-resistant membranes.

    Science.gov (United States)

    Swainsbury, David J K; Scheidelaar, Stefan; Foster, Nicholas; van Grondelle, Rienk; Killian, J Antoinette; Jones, Michael R

    2017-10-01

    Solubilisation of biological lipid bilayer membranes for analysis of their protein complement has traditionally been carried out using detergents, but there is increasing interest in the use of amphiphilic copolymers such as styrene maleic acid (SMA) for the solubilisation, purification and characterisation of integral membrane proteins in the form of protein/lipid nanodiscs. Here we survey the effectiveness of various commercially-available formulations of the SMA copolymer in solubilising Rhodobacter sphaeroides reaction centres (RCs) from photosynthetic membranes. We find that formulations of SMA with a 2:1 or 3:1 ratio of styrene to maleic acid are almost as effective as detergent in solubilising RCs, with the best solubilisation by short chain variants (SMA to solubilise RCs gradually declined when genetically-encoded coiled-coil bundles were used to artificially tether normally monomeric RCs into dimeric, trimeric and tetrameric multimers. The ability of SMA to solubilise reaction centre-light harvesting 1 (RC-LH1) complexes from densely packed and highly ordered photosynthetic membranes was uniformly low, but could be increased through a variety of treatments to increase the lipid:protein ratio. However, proteins isolated from such membranes comprised clusters of complexes in small membrane patches rather than individual proteins. We conclude that short-chain 2:1 and 3:1 formulations of SMA are the most effective in solubilising integral membrane proteins, but that solubilisation efficiencies are strongly influenced by the size of the target protein and the density of packing of proteins in the membrane. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  15. Applications of Microwave in Organic Synthesis: An Improved One-step Synthesis of Metallophthalocyanines and a New Modified Microwave Oven for Dry Reactions

    Directory of Open Access Journals (Sweden)

    Nathalie Bar

    2001-10-01

    Full Text Available Metallophthalocyanine complexes are obtained quickly and efficiently by the reaction of phthalodinitrile with hydrated metallic salts without solvent and under microwave irradiation. The use of a modified commercial microwave oven to perform this type of reactions under dry conditions is described. Metallophthalocyanines and metallododecachlorophthalocyanines of some divalent metals can be also obtained from phthalic or tetrachlorophthalic anhydrides with hydrated metallic salt and urea under microwave irradiation and without solvent.

  16. Effects of surface modification of talc on mechanical properties of polypropylene/talc composites

    Science.gov (United States)

    Liu, Keyan; Stadlbauer, Wolfgang; Zitzenbacher, Gernot; Paulik, Christian; Burgstaller, Christoph

    2016-03-01

    Low compatibility of polymer matrix and dispersed filler negatively affects the performance of polymeric composites. In order to improve the adhesion between the components in a compound the polymer matrix or/and the filler particles should be modified with a compatibilizer or/and a coupling agent. An overview of our current research on the effect of the addition of silane treated and untreated talc powders on the mechanical properties of polypropylene/talc composites is presented in this paper. Different silane coupling agents (3-aminopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane and 3-methacryloxypropyltrimethoxysilane) were used to improve the adhesion at the surface of talc powders. Maleic anhydride grafted polypropylene was utilized to increase the adhesion between the polypropylene matrix and talc powders. The content of maleic anhydride grafted polypropylene (MA-g-PP) was varied between 1 and 5 wt% in polypropylene/talc composites. The surface modification of talc powders has a significant effect on the interfacial structure and the mechanical properties such as tensile strength and impact strength of polypropylene/talc composites. The experiments show that polypropylene grafted with maleic anhydride together with silane surface treatment exhibits the highest potential for improvements in this field.

  17. Relationship between Surface Properties and In Vitro Drug Release from Compressed Matrix Containing Polymeric Materials with Different Hydrophobicity Degrees

    Directory of Open Access Journals (Sweden)

    Cristhian J. Yarce

    2017-01-01

    Full Text Available This work is the continuation of a study focused on establishing relations between surface thermodynamic properties and in vitro release mechanisms using a model drug (ampicillin trihydrate, besides analyzing the granulometric properties of new polymeric materials and thus establishing the potential to be used in the pharmaceutical field as modified delivery excipients. To do this, we used copolymeric materials derived from maleic anhydride with decreasing polarity corresponding to poly(isobutylene-alt-maleic acid (hydrophilic, sodium salt of poly(maleic acid-alt-octadecene (amphiphilic, poly(maleic anhydride-alt-octadecene (hydrophobic and the reference polymer hydroxyl-propyl-methyl-cellulose (HPMC. Each material alone and in blends underwent spectroscopic characterization by FTIR, thermal characterization by DSC and granulometric characterization using flow and compaction tests. Each tablet was prepared at different polymer ratios of 0%, 10%, 20%, 30% and 40%, and the surface properties were determined, including the roughness by micro-visualization, contact angle and water absorption rate by the sessile drop method and obtaining Wadh and surface free energy (SFE using the semi-empirical models of Young–Dupré and  Owens-Wendt-Rabel-Käelbe (OWRK, respectively. Dissolution profiles were determined simulating physiological conditions in vitro, where the kinetic models of order-zero, order-one, Higuchi and Korsmeyer–Peppas were evaluated. The results showed a strong relationship between the proportion and nature of the polymer to the surface thermodynamic properties and kinetic release mechanism.

  18. Modified Ureterosigmoidostomy

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective To introduce an operation procedure and evaluate the coutinence diversion results of the modified ureterosigmoidostomy after radical cystectomy. Methods Fourteen cases of bladder cancer or prostate carcinoma were operated on with modified Sigma pouch from Feb, 1998 to Dec, 1999. A longitudinal incision about 25 cm on the sigmoid uall was done to form a low pressure pouch. The vertex of the new pouch was fixed to sacrum. Both ends of ureters were anastomosed side to side and to form a big nipple and inserted into the top of pouch for 2 to 3 centimeters. Results It took about sixty five minutes to create a new low pressure pouch after radical cystectomy. Early complication of was found in two cases postoperatively, and cured with temporary colonostomy. Hydronephrosis and hypokalemia in one patient were cured by percutaneous anterograde ureter dilatation with balloon and oral replacement of potassium salt. All patients displayed urinary continence. No symptomatic renal infection or hypercholoraemic acidosis occurred. Conclusion Modified ureterosigmoidostomy is a safe procedure of urinary diversion and provides a big volume, low intravesical pressure pouch. The patients are free from the troublesome urine-bag, intermittert catheterization , and upper urinary tracts are protected effectively. The quality of life is satisfied.

  19. Investigation of the ageing effects on phenol-urea-formaldehyde binder and alkanol amine-acid anhydride binder coated mineral fibres

    DEFF Research Database (Denmark)

    Zafar, Ashar; Schjødt-Thomsen, Jan; Sodhi, R.

    2013-01-01

    . Principal Component Analysis (PCA) was applied on the positive and negative ToF-SIMS spectra of the PUF binder coated mineral fibres, showing a decrease in the concentration of the nitrogen containing peaks during ageing. This decrease was attributed to the depolymerisation of the binder due to hydrolysis......Phenol-Urea-Formaldehyde (PUF) binder coated mineral fibres' mechanical properties have been observed to degrade during ageing at elevated temperatures and humidity, while alkanol amine-acid anhydride binder based mineral fibres exhibited better ageing properties for same duration of ageing. X......-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS) were employed to identify the chemical changes occurring in the PUF binder coated mineral fibres and alkanol amine-acid anhydride binder coated mineral fibres during that ageing. The samples were aged in a climate...

  20. Efficient synthesis of zinc-containing mesoporous silicas by microwave irradiation method and their high activities in acetylation of 1,2-dimethoxybenzene with acetic anhydride

    Directory of Open Access Journals (Sweden)

    K. Bachari

    2016-09-01

    Full Text Available A series of acid zinc-containing mesoporous materials have been synthesized by microwave irradiation method with different Si/Zn ratios (Si/Zn = 100, 65, 15 and characterized by several spectroscopic techniques such as: N2 physical adsorption, ICP, XRD, TEM, FT-IR and a temperature-programmed-desorption (TPD of pyridine. The liquid phase of acetylation of 1,2-dimethoxybenzene with acetic anhydride has been investigated over this series of catalysts. In fact, the catalyst Zn-JLU-15 (15 showed bigger performance in the acid-catalyzed acetylation of 1,2-dimethoxybenzene employing acetic anhydride as an acylating agent. Furthermore, the kinetics of the acetylation of 1,2-dimethoxybenzene over these catalysts have also been investigated.

  1. Electronic Effects of Aluminum Complexes in the Copolymerization of Propylene Oxide with Tricyclic Anhydrides: Access to Well-Defined, Functionalizable Aliphatic Polyesters.

    Science.gov (United States)

    Van Zee, Nathan J; Sanford, Maria J; Coates, Geoffrey W

    2016-03-02

    The synthesis of well-defined and functionalizable aliphatic polyesters remains a key challenge in the advancement of emerging drug delivery and self-assembly technologies. Herein, we investigate the factors that influence the rates of undesirable transesterification and epimerization side reactions at high conversion in the copolymerization of tricyclic anhydrides with excess propylene oxide using aluminum salen catalysts. The structure of the tricyclic anhydride, the molar ratio of the aluminum catalyst to the nucleophilic cocatalyst, and the Lewis acidity of the aluminum catalyst all influence the rates of these side reactions. Optimal catalytic activity and selectivity against these side reactions requires a careful balance of all these factors. Effective suppression of undesirable transesterification and epimerization was achieved even with sterically unhindered monomers using a fluorinated aluminum salph complex with a substoichiometric amount of a nucleophilic cocatalyst. This process can be used to synthesize well-defined block copolymers via a sequential addition strategy.

  2. Mixed anhydrides (phosphoric-carboxyl) are also formed in the esterification of 5'-amp with n-acetylaminoacyl imidazolides - Implications regarding the origin of protein synthesis

    Science.gov (United States)

    Wickramasinghe, Nalinie S. M. D.; Lacey, James C., Jr.

    1992-01-01

    Procedure for the formation of aminoacyl esters of monoribonucleotides with aminoacyl imidazolides were first reported by Gottikh et al. (1970) and summarized in 1970. This reaction has been widely used by us and numbers of other workers as a convenient means of preparing aminoacyl esters of nucleotides. We have previously reported that, under conditions of excess imidazolide, large amounts of bis 2', 3' esters are formed in addition to the monoesters. However, to our knowledge, no one has reported that in addition to the esters, relatively large amounts of the mixed anhydride, with the amino acid carboxyl attached to the phosphate, are also formed at short reaction times. We report here on the relative amounts of anhydride and esters formed in this reaction of racemic mixtures of eleven N-acetyl amino acid imidazolides with 5'-AMP and discuss the relevance of the findings to the origin of protein synthesis.

  3. Synthesis of high molecular weight polylactic acid from aqueous lactic acid co-catalyzed by tin(II)chloride dihydrate and succinic anhydride

    Institute of Scientific and Technical Information of China (English)

    LEI Ziqiang; BAI Yanbin; WANG Shoufeng

    2005-01-01

    Polylactic acid was synthesized from commercial available cheap aqueous lactic acid (85%―90% w/w) using succinic anhydride and SnCl2·2H2O as catalyst in the absence of organic solvents. As a result, polylactic acid with a molecular weight of 60000 was prepared in 10 h. The new procedure is much simple, cheap and outstanding in that the start material is aqueous lactic acid; the catalytic system is environmentally benign.

  4. N-甲酰-L-天冬氨酸酐的合成%Synthesis of N-Formyl-L-aspartic Anhydride

    Institute of Scientific and Technical Information of China (English)

    冷一欣; 芮新生; 马江权; 孙豪义; 周宏斌

    2001-01-01

    N-Formyl-L-aspartic anhydride was prepared by the reaction of L-aspartic acid and formic acid with magnesium oxide catalyst in acetic anhydride solvent.Effects of temperature,operation time and molar ratio of formic acid and acetic anhydride were discussed.The optimum operation conditions were temperature 50 ℃,operation time 5 h, molar ratio of formic acid to L-aspartic acid 1.6∶1.0 and molar ratio of acetic anhydride to L-aspartic acid 2.3∶1.0.The yield was 90.35%.%在乙酸酐溶剂中,以氧化镁为催化剂,L-天冬氨酸与甲酸进行甲酰化反应并脱水生成N-甲酰-L-天冬氨酸酐。考察了温度、时间、甲酸和乙酸酐用量比对反应的影响,得到了优化的反应条件为:反应温度50 ℃,反应时间5 h,甲酸与L-天冬氨酸的物质的量比为1.6∶1.0,乙酸酐与L-天冬氨酸的物质的量比为2.3∶1.0,此时产物收率达90.35%。

  5. STUDY OF CARBONYLATION OF METHANOL TO ACETIC ACID AND ACETIC ANHYDRIDE OVER A BIDENTATE POLYMER BOUND CIS-DICARBONYLRHODIUM COMPLEX AS CATALYST

    Institute of Scientific and Technical Information of China (English)

    WANG Xiaojun; LIU Zhongyang; PAN Pinglai; YUAN Guoqing

    1996-01-01

    Copolymer of 2-vinylpyridine and vinylacetate coordinated with dicarbonylrhodium used as a catalyst for carbonylation of methanol to acetic acid and anhydride has been studied. The structural characteristics of the copolymer ligand and complex, and the influences of the reaction conditions on the carbonylation catalyzed by this polymer complex have been investigated. In comparison with small molecule catalyst of Rh complex, the bidentate copolymer coordinated complex has better thermal stability. The reaction mechanism of the carbonylation reaction is also illustrated.

  6. Butanol Alcoholysis of Succinic Anhydride Under Neutral Condition%中性条件下丁二酸酐的丁醇解

    Institute of Scientific and Technical Information of China (English)

    高艳萍; 张利萍

    2011-01-01

    Alcoholysis of succinic anhydride and n - butyl alcohol takes place without catalysts and the monobutyl succinie forms. The IR and MS spectra of the products are measured respectively. The factors such as the molar radio between succinic anhydride and n - butanol, raction time are discussed. The radio of succinic acid to n - butanol is 1:3 ,the reaction time is 2h, alcoholysis radio is up to 95.8% ;the reaction time is over 2.5h,succinic anhydride has been alcoholyzed and a little amount of dibutyl has formed.%丁二酸酐和正丁醇在无催化剂参与下,直接醇解生成丁二酸正丁单酯。用IR谱和MS谱分别对产物进行了结构表征。反应讨论了物质的量比、反应时间对醇解反应的影响。当酸酐与醇的物质的量比为1:3,反应2h时,酸酐醇解率已达到95.8%;反应2.5h以上时,酸酐完全醇解,并且有少量丁二酸二丁酯生成。

  7. Synthesis and Evaluation of Stearic Acid Diethanolamide Acrylate Ester/Maleic Anhydride/Vinyl Acetate (SMV) Copolymer Diesel Fuel Depressant%硬脂酸二乙醇酰胺丙烯酸单酯-马来酸酐-醋酸乙烯酯共聚物柴油降凝剂制备及评价

    Institute of Scientific and Technical Information of China (English)

    张艾秋; 刘侠; 韩艳双

    2011-01-01

    以硬脂酸二乙醇酰胺丙烯酸单酯、马来酸酐、醋酸乙烯酯为单体,采用溶液聚合法合成了硬脂酸二乙醇酰胺丙烯酸单酯-马来酸酐-醋酸乙烯酯降凝剂,考察了单体物质的量比、引发剂用量、聚合温度对降凝效果的影响.通过红外光谱对共聚物分子结构进行了表征,结果表明,合成的分子结构和设计目标分子结构相符.此降凝剂可使东营0#柴油的凝点降低7℃,与AH - BSF216型降凝剂复配后具有较好的降凝效果.

  8. 炭改性对Ni/Al2O3催化剂顺酐加氢合成γ-丁内酯反应性能的影响%Effect of Carbon Modification on Ni/Al2O3 Catalyst for Hydrogenation of Maleic Anhydride to Butyrolactone

    Institute of Scientific and Technical Information of China (English)

    李海涛; 张鸿喜; 陈昊然; 张因; 高春光; 赵永祥

    2010-01-01

    通过热解蔗糖/Al2O3前驱体的方法制备了炭包覆改性Al2O3(CCA)载体,并采用等体积浸渍制备了负载量17 %的镍基催化剂.对载体及相应催化剂进行了TPO-MS、N2物理吸附、TPR、XRD等测试表征,并考察了催化剂顺酐(MA)加氢合成γ-丁内酯(GBL)的反应性能.结果表明,适量炭的引入改变了载体Al2O3的表面性质,使金属-载体相互作用减弱,活性组分镍的分散度提高,催化剂在MA加氢反应中表现出高的GBL选择性.当Al2O3中引入8.9 %的炭时,催化剂表现出最高的催化活性,在210 ℃,5 MPa氢气压力下反应3 h时,MA转化率达98%以上,GBL选择性达91.71 %.

  9. Study on deactivation and regeneration of Cu-CeO2-Al2O3 catalyst for hydrogenation of maleic anhydride to γ-butyrolactone%顺酐加氢制γ-丁内酯Cu-CeO2-Al2O3催化剂失活与再生研究

    Institute of Scientific and Technical Information of China (English)

    邱爱玲

    2015-01-01

    采用共沉淀法制备了Cu-CeO2-Al2 O3 (CCA)催化剂,用于顺酐(MA)常压气相加氢制γ-丁内酯(GBL)反应,表现了很好的催化性能,MA的转化率和GBL的选择性均达到100%,然而催化剂容易失活.采用扫描电子显微镜、热失重、N2O分解和X射线粉末衍射表征研究了CCA催化剂的失活原因和中间产物琥珀酸酐(SA)对CCA催化剂失活的影响,并考察了N2-air-H2法对CCA催化剂的再生效果;同时,通过设计试验对CCA催化剂上MA加氢制GBL反应历程进行了分析.结果表明:CCA催化剂的失活主要是由于表面沉积物的生成覆盖了催化剂表面活性位,而表面沉积物的生成与SA的浓度有关;通过N2-air-H2再生法能够完全恢复CCA催化剂的催化性能.此外,给出了CCA催化剂上MA加氢制GBL可能的反应历程.

  10. Preparation and properties of polyamide 6-clay nanocomposites/ethylene-octene copolymer-grafted-maleic anhydride blends%尼龙-6/蒙脱土纳米复合材料用POE-g-MAH改性及性能研究

    Institute of Scientific and Technical Information of China (English)

    宋波; 黄锐; 魏刚

    2004-01-01

    制备了尼龙-6(PA6)/马来酸酐接枝乙烯-1-辛烯共聚物(POE-g-MAH)和PA6-蒙脱土纳米复合物(NCH)/POE-g-MAH两种复合材料,其脆韧转变点都是在POE-g-MAH质量分数为8%~10%.在脆韧转变点前,PA6/POE-g-MAH和NCH/POE-g-MAH的缺口冲击强度几乎相同;在脆韧转变点后,NCH/POE-g-MAH的冲击强度远高于PA6/POE-g-MAH.复合材料的拉伸强度都随POE-g-MAH的增加而线性下降,在相同POE-g-MAH含量时,NCH/POE-g-MAH的拉伸强度比PA6/POE-g-MAH的低4 MPa左右.

  11. Equilibrium of Extraction of Succinic, Malic, Maleic and Fumaric Acids with Trioctylamine%三辛胺萃取丁二酸、苹果酸、马来酸、富马酸特性的研究

    Institute of Scientific and Technical Information of China (English)

    李振宇; 秦炜; 汪敏; 黄焱; 戴猷元

    2002-01-01

    Extraction equilibrium features of succinic acid, malic acid, maleic acid and fumaric acid were investigated systematically with trioctylamine (TOA) in chloroform, 4-methyl-2-pentanone (MIBK) and 1-octanol. Fourier transform-infrared (FTIR) spectroscopic analysis of organic samples loaded with the acid shows that amine forms 1:1 complex of ion-pair association with succinic acid, malic acid and maleic acid, and 1:1, 2:1 complex of ion-pair association with fumaric acid. It is proposed that the complex forms depend on the second dissociation constant of the dibasic acid, pKa2. Results of equilibrium experiments show that diluents affect extraction behavior, and depend on the solute concentration. Protic diluents, chloroform and 1-octanol, are more effective than the others when the equilibrium solute concentration is lower than 1:1 stoichiometry of TOA to acid, otherwise the extraction ability shows that MIBK>l-octanol>chloroform for malic and maleic acids, and 1-octanol>MIBK>chloroform for succinic acid. Overloading (solute concentration in organic phase is lager than TOA concentration) appears for all of the studied acids, and the sequence of overloading amount is the same as that of distribution constant of diluent. The results show that the sequence of extraction ability of different acid is the same as that of acidity at low equilibrium solute concentrations, while it is the same as the sequence of hydrophobicity at high equilibrium concentrations.

  12. Development of a guided bone regeneration device using salicylic acid-poly(anhydride-ester) polymers and osteoconductive scaffolds.

    Science.gov (United States)

    Mitchell, Ashley; Kim, Brian; Cottrell, Jessica; Snyder, Sabrina; Witek, Lukasz; Ricci, John; Uhrich, Kathryn E; O'Connor, J Patrick

    2014-03-01

    Successful repair of craniofacial and periodontal tissue defects ideally involves a combined therapy that includes inflammation modulation, control of soft tissue infiltration, and bone regeneration. In this study, an anti-inflammatory polymer, salicylic acid-based poly(anhydride-ester) (SAPAE) and a three-dimensional osteoconductive ceramic scaffold were evaluated as a combined guided bone regeneration (GBR) system for concurrent control of inflammation, soft tissue ingrowth, and bone repair in a rabbit cranial defect model. At time periods of 1, 3, and 8 weeks, five groups were compared: (1) scaffolds with a solid ceramic cap (as a GBR structure); (2) scaffolds with no cap; (3) scaffolds with a poly(lactide-glycolide) cap; (4) scaffolds with a slow release SAPAE polymer cap; and (5) scaffolds with a fast release SAPAE polymer cap. Cellular infiltration and bone formation in these scaffolds were evaluated to assess inflammation and bone repair capacity of the test groups. The SAPAE polymers suppressed inflammation and displayed no deleterious effect on bone formation. Additional work is warranted to optimize the anti-inflammatory action of the SAPAE, GBR suppression of soft tissue infiltration, and stimulation of bone formation in the scaffolds and create a composite device for successful repair of craniofacial and periodontal tissue defects.

  13. Anhydride-functional silane immobilized onto titanium surfaces induces osteoblast cell differentiation and reduces bacterial adhesion and biofilm formation

    Energy Technology Data Exchange (ETDEWEB)

    Godoy-Gallardo, Maria, E-mail: maria.godoy.gallardo@upc.edu [Biomaterials, Biomechanics and Tissue Engineering Group, Department of Materials Science and Metallurgy, Technical University of Catalonia (UPC), ETSEIB, Av. Diagonal 647, 08028 Barcelona (Spain); Centre for Research in NanoEngineering (CRNE) — UPC, C/ Pascual i Vila 15, 08028 Barcelona (Spain); Guillem-Marti, Jordi, E-mail: jordi.guillem.marti@upc.edu [Biomaterials, Biomechanics and Tissue Engineering Group, Department of Materials Science and Metallurgy, Technical University of Catalonia (UPC), ETSEIB, Av. Diagonal 647, 08028 Barcelona (Spain); Centre for Research in NanoEngineering (CRNE) — UPC, C/ Pascual i Vila 15, 08028 Barcelona (Spain); Sevilla, Pablo, E-mail: psevilla@euss.es [Department of Mechanics, Escola Universitària Salesiana de Sarrià (EUSS), C/ Passeig de Sant Bosco, 42, 08017 Barcelona (Spain); Manero, José M., E-mail: jose.maria.manero@upc.edu [Biomaterials, Biomechanics and Tissue Engineering Group, Department of Materials Science and Metallurgy, Technical University of Catalonia (UPC), ETSEIB, Av. Diagonal 647, 08028 Barcelona (Spain); Centre for Research in NanoEngineering (CRNE) — UPC, C/ Pascual i Vila 15, 08028 Barcelona (Spain); Gil, Francisco J., E-mail: francesc.xavier.gil@upc.edu [Biomaterials, Biomechanics and Tissue Engineering Group, Department of Materials Science and Metallurgy, Technical University of Catalonia (UPC), ETSEIB, Av. Diagonal 647, 08028 Barcelona (Spain); Centre for Research in NanoEngineering (CRNE) — UPC, C/ Pascual i Vila 15, 08028 Barcelona (Spain); and others

    2016-02-01

    Bacterial infection in dental implants along with osseointegration failure usually leads to loss of the device. Bioactive molecules with antibacterial properties can be attached to titanium surfaces with anchoring molecules such as silanes, preventing biofilm formation and improving osseointegration. Properties of silanes as molecular binders have been thoroughly studied, but research on the biological effects of these coatings is scarce. The aim of the present study was to determine the in vitro cell response and antibacterial effects of triethoxysilypropyl succinic anhydride (TESPSA) silane anchored on titanium surfaces. X-ray photoelectron spectroscopy confirmed a successful silanization. The silanized surfaces showed no cytotoxic effects. Gene expression analyses of Sarcoma Osteogenic (SaOS-2) osteoblast-like cells cultured on TESPSA silanized surfaces reported a remarkable increase of biochemical markers related to induction of osteoblastic cell differentiation. A manifest decrease of bacterial adhesion and biofilm formation at early stages was observed on treated substrates, while favoring cell adhesion and spreading in bacteria–cell co-cultures. Surfaces treated with TESPSA could enhance a biological sealing on implant surfaces against bacteria colonization of underlying tissues. Furthermore, it can be an effective anchoring platform of biomolecules on titanium surfaces with improved osteoblastic differentiation and antibacterial properties. - Highlights: • TESPSA silane induces osteoblast differentiation. • TESPSA reduces bacterial adhesion and biofilm formation. • TESPSA is a promising anchoring platform of biomolecules onto titanium.

  14. In Vivo Evaluation of Nerve Guidance Conduits Comprised of a Salicylic Acid-based Poly(anhydride-ester) Blend

    Science.gov (United States)

    Lee, Yong Soo

    Unlike the central nervous system, peripheral nervous system can regenerate from injury. However, without surgical intervention, the results are often poor. Autologous nerve grafting is the golden standard for repairing peripheral nerve injury; but limited donor availability and donor site morbidity led researchers to seek alternative methods. Among the many alternative treatment options, synthetic nerve guidance conduits (NGCs) have been most actively developed. The goal of NGCs is to serve as a physical scaffold that aids the axonal regeneration process while preventing scar tissue formation that interferes with regeneration. Biocompatible and biodegradable NGCs would provide additional benefits: minimize foreign body reaction and avoid secondary surgeries to remove NGCs. We developed a unique NGC that incorporated the characteristics described above and can release an anti-inflammatory drug, salicylic acid. In this work, in vivo assays were performed to evaluate NGCs fabricated from a poly(anhydride-ester) blend. To further assist in the regeneration process, bovine native collagen type I hydrogel were inserted into the NGCs lumen which was then implanted in femoral nerve of mice for up to 16 weeks. These studies demonstrated in vivo biodegradability, biocompatibility, and axonal regeneration following an injury to the peripheral nerve. These studies provide greater insights into the importance of designing NGCs and how they aid in regeneration and functional recovery of subjects.

  15. Using monosaccharide anhydrides to estimate the impact of wood combustion on fine particles in the Helsinki Metropolitan Area

    Energy Technology Data Exchange (ETDEWEB)

    Saarnio, K.; Saarikoski, S. [Finnish Meteorological Institute, Helsinki (Finland); Niemi, J.V. [HSY Helsinki Region Environmental Services Authority, Helsinki (Finland)

    2012-11-01

    The spatiotemporal variation of ambient particles under the influence of biomass burning emissions was studied in the Helsinki Metropolitan Area (HMA) in selected periods during 2005-2009. Monosaccharide anhydrides (MAs; levoglucosan, mannosan and galactosan), commonly known biomass burning tracers, were used to estimate the wood combustion contribution to local particulate matter (PM) concentration levels at three urban background sites close to the city centre, and at three suburban sites influenced by local small-scale wood combustion. In the cold season (October-March), the mean MAs concentrations were 115-225 ng m{sup -3} and 83-98 ng m{sup -} {sup 3}at the suburban and urban sites, respectively. In the warm season, the mean MAs concentrations were low (19-78 ng m{sup -3}), excluding open land fire smoke episodes (222-378 ng m{sup -}3{sup )}. Regionally distributed wood combustion particles raised the levels over the whole HMA while particles from local wood combustion sources raised the level at suburban sites only. The estimated average contribution of wood combustion to fine particles (PM{sub 2.5}) ranged from 18% to 29% at the urban sites and from 31% to 66% at the suburban sites in the cold season. The PM measurements from ambient air and combustion experiments showed that the proportions of the three MAs can be utilised to separate the wildfire particles from residential wood combustion particles. (orig.)

  16. Interaction of ozone exposure with airway hyperresponsiveness and inflammation induced by trimellitic anhydride in sensitized guinea pigs

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Jian; Chung, K.Fan [National Heart & Lung Institute, London (United Kingdom)

    1997-09-01

    The effect of prior ozone (O{sub 3}) exposure on airway hyperresponsiveness and inflammation induced by trimellitic anhydride (TMA) has been investigated in TMA-sensitized guinea pigs. Airway responsiveness was measured as the concentration of acetylcholine needed to increase baseline lung resistance (RL) by 300% (PC300). Ozone (3 ppm, for 3 h) caused an increase in-log PC300 at 1 h after exposure, with return of -log PC300 to control levels at 8 h. Ozone also increased baseline RL at 8 h. TMA challenge increase -log PC300 in TMA-sensitized guinea pigs at 8 h after challenge from 3.85 {+-} 0.09 to 4.11 {+-} 0.09. Ozone exposure prior to TMA challenge prevented the induction of airway hyperresponsiveness with a mean -log PC300 of 3.51 {+-} 0.20, which was not different from that of control TMA-Sensitized group. Baseline RL was significantly higher in ozone-pretreated animals after TMA challenge when compared to those of either control or challenged with TMA alone. Ozone had no effect on TMA challenge-induced BAL eosinophilia and neutrophilia. We conclude that a single exposure to ozone inhibits the increase in airway responsiveness, but increases the bronchoconstrictor response induced by TMA in TMA-Sensitized guinea pigs; however, the inflammatory airway response to TMA is unchanged by preexposure to ozone. 29 refs., 2 figs., 1 tab.

  17. In vitro release of clomipramine HCl and buprenorphine HCl from poly adipic anhydride (PAA) and poly trimethylene carbonate (PTMC) blends.

    Science.gov (United States)

    Dinarvand, Rassoul; Alimorad, Mohammed Massoud; Amanlou, Massoud; Akbari, Hamid

    2005-10-01

    Controlled drug-delivery technology is concerned with the systematic release of a pharmaceutical agent to maintain a therapeutic level of the drug in the body for modulated and/or prolonged periods of time. This may be achieved by incorporating the therapeutic agent into a degradable polymer vehicle, which releases the agent continuously as the matrix erodes. In this study, poly trimethylene carbonate (PTMC), an aliphatic polycarbonate, and poly adipic anhydride (PAA), an aliphatic polyanhydride, were synthesized via melt condensation and ring-opening polymerization of trimethylene carbonate and adipic acid, respectively. The release of clomipramine HCl and buprenorphine HCl from discs prepared with the use of PTMC-PAA blends in phosphate buffer (pH 7.4) are also described. Clomipramine HCl and buprenorphine HCl were both used as hydrophilic drug models. Theoretical treatment of the data with the Peppas model revealed that release of clomipramine HCl (5%) in devices containing 70% PTMC or more followed a Fickian diffusion model. However, the releases of buprenorphine HCl (5%) in the same devices were anomalous. For devices containing 50% and more PAA, surface erosion may play a significant role in the release of both molecules.

  18. Immunosuppression of the Trimellitic Anhydride-Induced Th2 Response by Novel Nonanatural Products Mixture in Mice

    Directory of Open Access Journals (Sweden)

    Min-Jung Bae

    2013-01-01

    Full Text Available Many natural dietary products prevent or cure allergic inflammation; however, the ability of mixtures of these natural medicinals to suppress allergic skin inflammation is unknown. We examined the inhibitory effects of nonanatural products mixture (NPM-9, which provides immunoregulatory activation, on Th2-mediated skin allergic inflammation. Oral administration of NPM-9 in mice reduced ear thickness and specific IgE production in trimellitic anhydride- (TMA-induced contact hypersensitivity (CHS. NPM-9 also suppressed IL-4 and IL-1β production in splenocytes but prevented only TMA-induced IL-1β production in inflamed ears. To characterize the mechanism of this effect, we examined NPM-9 immunosuppression on an OVA-induced Th2 allergic state. Oral administration of NPM-9 inhibited Th2-mediated serum IgE overproduction. NPM-9 also downregulated the polarized Th2 response, whereas it upregulated Th1 response in splenocytes. These data suggest that NPM-9 may be a useful therapeutic agent for allergic inflammatory diseases through its suppression of the Th2-mediated allergic response.

  19. Microwave-Assisted Solvent-Free Acetylation of Cellulose with Acetic Anhydride in the Presence of Iodine as a Catalyst

    Directory of Open Access Journals (Sweden)

    Feng Xu

    2009-09-01

    Full Text Available In this work an optimization of the solvent-free acetylation of cellulose with acetic anhydride under microwave heating with iodine as a catalyst was performed. The optimized parameters included the microwave irradiation power from 300 W to 800 W, the reaction time between 5 to 40 min, the reaction temperature from 80 to 130 °C, and the amount of iodine from 1 to 15 mol%. The extent of the acetylation was measured by yield and the degree of substitution (DS, which was determined by a back-titration method. Acetylated cellulose was characterized by FT-IR, CP/MAS 13C-NMR, WRXD, and thermogravimetric analysis. The results showed that within the range of catalyst amounts studied, the DS increased as the amount of iodine used increased, however, it was barely affected by microwave output. It was also found that the reaction time and temperature had an active influence on the extent of acetylation, however, this did not mean that at the higher temperature a better acetylation of cellulose would be obtained. The optimal reaction time and temperature found in this work were 30 min and 130 °C.

  20. FTIR and color change of the modified wood as a result of artificial light irradiation.

    Science.gov (United States)

    Rosu, Dan; Teaca, Carmen-Alice; Bodirlau, Ruxanda; Rosu, Liliana

    2010-06-01

    The effect of UV-visible light irradiation on the changes in color and chemical composition of the surfaces of Abies alba L. (fir, a softwood), non-modified and chemically modified, was studied. Chemical modification of the wood was performed by reaction with succinic anhydride in xylene at different concentration values. The wood samples were irradiated in air using a rotative device equipped with a middle pressure mercury lamp. Analysis of the color changes in wood surfaces during photo-degradation was carried out by measuring CIELAB parameters. Fourier transform infrared spectroscopy was used to study chemical changes caused by light irradiation. Irradiation modified physical and chemical characteristics of wood surfaces and resulted in rapid color changes, degradation of lignin and increased content of chromophoric groups on the wood surfaces. Color changes (DeltaE(ab)) correlate well with degradation of lignin.