Kinetics of waterborne fluoropolymers prepared by one-step semi-continuous emulsion polymerization of chlorotrifluoroethylene, vinyl acetate, butyl acrylate and Veova 10

Science.gov (United States)

Liu, H. Z.; Wang, M. H.; Wang, Z. F.; Bian, J. M.

2018-01-01

Due to using gaseous fluorine monomer with toxicity, waterborne fluoropolymers are synthesized by semi-continuous high-pressure emulsion polymerization method which differs from free-pressure emulsion polymerization. To dates, the research on preparing process and kinetics for high-pressure emulsion polymerization is reported relatively less, which hinders researchers from understanding of mechanisms for monomer-fluorinated emulsion polymerization. The paper also provides a new method by element auxiliary analysis to calculate kinetics parameters of high-pressure emulsion polymerization. Based on aforementioned consideration, waterborne fluoropolymers were prepared by copolymerization of chlorotrifluoroethylene (CTFE), vinyl acetate (VAc), butyl acrylate (BA) and vinyl ester of versatic acid (Veova 10) using potassium persulfate as initiator and mixed surfactants. The kinetics of emulsion polymerization of waterborne fluoropolymers was then investigated. Effects of emulsifier concentration, initiator concentration, and polymerization temperature on polymerization rate (Rp) were evaluated, and relationship was described as Rp∝[I]0.10 and Rp∝[E]0.12. The apparent activation energy was determined to be 33.61 kJ·mol-1. Moreover, the relative conversion rate of CTFE with the other monomers was observed, and results indicated that CTFE monomer more uniformly copolymerized with the other monomers. The resulting emulsion properties and pressure change in an autoclave were evaluated at different stirring rates. The initial reaction time, defined as the beginning time of dropwise addition, was determined by the change in solid content and particle size of emulsion.

Microstructural characterization of a novel methyl acrylate-ethyl acrylate copolymer system

Energy Technology Data Exchange (ETDEWEB)

Olivares, M.; Castano, V.M. [Instituto de Fisica, UNAM, A.P. 1-1010, Queretaro, Mexico (Mexico); Molina, J.P.; Vazquez, F. [Facultad de Quimica UAEMex, Paseo Tollocan esq. Paseo Colon, Toluca, Estado de Mexico (Mexico)

1998-12-31

A number of different compositions of a novel methyl acrylate-ethyl acrylate copolymer were prepared by emulsion polymerization with potassium persulfate as initiator. The compositions synthesized were: 100/0, 75/25, 50/50, 25/75 and 0/100 on weight of methyl acrylate/ethyl acrylate at different temperatures and concentrations of initiators. The effect of other conditions were also studied. The samples were analyzed by Transmission Electron Microscopy. It was found that the size of aggregates and dispersion on sizes are controlled by the synthesis conditions, result partially supported by light scattering. (Author)

Microstructural characterization of a novel methyl acrylate-ethyl acrylate copolymer system

International Nuclear Information System (INIS)

Olivares, M.; Castano, V.M.; Molina, J.P.; Vazquez, F.

1998-01-01

A number of different compositions of a novel methyl acrylate-ethyl acrylate copolymer were prepared by emulsion polymerization with potassium persulfate as initiator. The compositions synthesized were: 100/0, 75/25, 50/50, 25/75 and 0/100 on weight of methyl acrylate/ethyl acrylate at different temperatures and concentrations of initiators. The effect of other conditions were also studied. The samples were analyzed by Transmission Electron Microscopy. It was found that the size of aggregates and dispersion on sizes are controlled by the synthesis conditions, result partially supported by light scattering. (Author)

Radiation crosslinking of poly(butyl acrylate) during polymerization and grafted copolymerization with Cr(III) crosslinked collagen

International Nuclear Information System (INIS)

Pietrucha, K.; Kroh, J.

1984-01-01

Enhanced crosslinking of synthetic polymer simultaneous with grafting and homopolymerization processes have been observed in irradiated leather tanned with Cr(III) and embedded with aqueous emulsions of butyl acrylate. Extent of poly(butyl acrylate) crosslinking during copolymerization was found to be approximately one order higher than in the case of radiation polymerization of butyl acrylate in emulsion. New method for isolation of grafted copolymer based on degradation of collagen has been developed. The extent of crosslinking was calculated from the swelling data. (author)

On-line monitoring and composition control of the emulsion copolymerization of VeoVA 9 and butyl acrylate by Raman spectroscopy

NARCIS (Netherlands)

van den Brink, H.J.T.; Pepers, M.L.H.; Herk, van A.M.; German, A.L.

2001-01-01

The batch and semi-continuous emulsion copolymn. of Bu acrylate and vinyl neononanoate (VeoVA 9) were monitored by remote online Raman spectroscopy. Monomer concns. were calcd. in real-time by a classical least squares (CLS) approach using the vinyl regions of the Raman spectra. During the batch

Radiation crosslinking of poly(butyl acrylate) during polymerization and grafted copolymerization with Cr(III) crosslinked collagen

International Nuclear Information System (INIS)

Pietrucha, K.; Kroh, J.

1986-01-01

Enhanced crosslinking of synthetic polymer simultaneously with grafting and homopolymerization processes has been observed in irradiated leather tanned with Cr(III) and embedded with aqueous emulsions of butyl acrylate. The extent of poly(butyl acrylate) crosslinking during copolymerization was found to be approximately one order higher than in the case of radiation polymerization of butyl acrylate in emulsion. A new method for isolation of grafted copolymer based on degradation of collagen has been developed. The extent of crosslinking was calculated from the swelling data. (author)

Preparation of Fe 3O 4/poly(styrene-butyl acrylate-[2-(methacryloxy)ethyl]trimethylammonium chloride) by emulsifier-free emulsion polymerization and its interaction with DNA

Science.gov (United States)

Li, Xiaolong; Liu, Guoqiang; Yan, Wei; Chu, Paul K.; Yeung, Kelvin W. K.; Wu, Shuilin; Yi, Changfeng; Xu, Zushun

2012-04-01

Cationic magnetic polymer particles Fe3O4/poly(styrene-butyl acrylate-[2-(methacryloxy)ethyl]trimethylammonium chloride), a type of potential gene carrier, were prepared by emulsifier-free emulsion polymerization with oleic acid modified magnetite Fe3O4, styrene, butyl acrylate and [2-(methacryloxy)ethyl]trimethylammonium chloride) (METAC). The morphology of the particles was characterized by transmission electron microscopy and the composites of particles were characterized by FT-IR spectroscopy, X-ray diffraction. These results showed that magnetic particles were well dispersed in polymers with the content of about 15%(wt/wt). The composites exhibited superparamagnetism and possessed a certain level of magnetic response. The interactions between the particles with calf-thymus DNA (ct DNA) were confirmed by zeta potential measurement, UV-vis spectroscopy and fluorescence spectroscopy. The DNA-binding capacity determined by the agarose gel electrophoresis showed good binding capacity of the emulsion to DNA. These results suggested the potential of the cationic magnetic polymer emulsion as gene target delivery carrier.

EFFECTS OF ω-ACRYLOYL POLY(ETHYLENE OXIDE) MACROMONOMER ON EMULSIFIER-FREE EMULSION COPOLYMERIZATION OF METHYL METHACRYLATE AND n-BUTYL ACRYLATE

Institute of Scientific and Technical Information of China (English)

无

1998-01-01

Well-defined nonionic hydrophilic ω-acryloyl poly(ethylene oxide) macromonomer (PEO-A) has been prepared by living anionic polymerization of ethylene oxide with diphenyl methyl potassium as the initiator and acryloyl chloride as the reaction terminating agent. The polymer was characterized by FTIR and SEC. The emulsifier-free emulsion polymerization of methyl methacrylate (MMA) and n-butyl acrylate (BA) containing various concentrations of PEO-A was studied. In all cases stable emulsion coplymerizations of MMA and BA were obtained. The stabilizing effect was found to be dependent on the molecular weight and the feed amount of the macromonomer.

Emulsion Polymerization of Etyl Acrylate: The Effect of Surfactant, Initiator Concentration and PolymerizationTechnique on Particle Size Distribution

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Nitri Arinda

2009-04-01

Full Text Available Emulsion polymerization was conducted using ethyl acrylate monomer. Theeffect of sodium lauryl sulfate concentration, ammonium persulfate concentration, the various of polymerizationtechniques and feeding time to the conversion, particle size and its distribution were observed. The purpose of thisresearch is to obtain the optimum condition of ethyl acrylate homopolymer with particle size around 100 nm, to get theparticle size distribution monodisperse and to get solid content value of the experiment closed to its theoretical value.The optimum condition then could be applied in shell polymerization of core-shell polymers. The results of the researchshowed that semicontinuous technique obtained optimum sodium lauryl sulfate concentration at 20 CMC (criticalmicelle concentration and ammonium persulfate concentration is 3%. By using batch technique that the biggestparticle size is 123 nm with conversion 95.8% and monodisperse. The shorter of feeding time the more monomer ofethyl acrylate being polymerized, it is showed by the higher conversion up to 94.4% and the bigger particle size is107.9 nm.

Improvement in Wood Bonding Strength of Poly (Vinyl Acetate-Butyl Acrylate Emulsion by Controlling the Amount of Redox Initiator

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Yun Zhang

2018-01-01

Full Text Available Polyvinyl acetate emulsion adhesive has been widely used due to its good bonding performance and environmentally friendly properties. Indeed, the bonding performance can be further improved by copolymerizing with other monomers. In this study, the effect of the adjunction of redox initiator (hydrogen peroxide–tartaric acid, H2O2–TA on the properties of the poly (vinyl acetate-butyl acrylate (P (VAc–BA emulsion adhesive was investigated. With increasing dosage, the reaction became more complete and the obtained film was more compact, as identified via SEM. The core-shell structure of the emulsion particles was confirmed via TEM. Results indicate that while the initiator content increased from 0.5 to 1.0%, a clearer core-shell structure was obtained and the bonding strength of the plywood improved from 2.34 to 2.97 MPa. With the further incorporation of H2O2–TA (i.e., 1.5%, the bonding performance deteriorated. The optimum wood bonding strength (2.97 MPa of the prepared P (VAc-BA emulsion adhesive was even better than that (2.55 MPa of a commercial PVAc emulsion adhesive, suggesting its potential application for the wood industry.

Effect of monomer concentration on the kinetics of emulsifier-free emulsion polymerization of Vinyl Acetate and Methyl Acrylate

International Nuclear Information System (INIS)

Mohammad Beigi, H. R.

2001-01-01

The effect of monomer concentration on the kinetics of the emulsifier-free emulsion polymerization of vinyl acetate and methyl acrylate were studied. The polymerizations were carried out using potassium persulfate as the initiator. Form the electron micrographs of the resulting lattices, monodisperse PVAc and PMA lattices with particle diameters varying between 149-443 mm and 112-497 nm, respectively were processed. Uniformity of particle size indicated that nucleation of stable particle occurs early in the polymerization process. The polymerization rate was found to be proportional to the 0.88 and 1.5 power of the initial monomer concentration of vinyl acetate and methyl acrylate, respectively. Higher monomer concentration results in fewer particles and larger final particle diameter. With increasing monomer solubility in water the size of particle decreases and its distribution broadens

STABILITY OF EMULSIFIER-FREE EMULSION COPOLYMERIZATION OF METHYL METHACRYLATE/ BUTYL ACRYLATE/SODIUM MONO(ETHYL POLYOXYETHYLENE) MALEATE

Institute of Scientific and Technical Information of China (English)

Mao-gen Zhang; Zhi-xue Weng; Zhi-ming Huang; Zu-ren Pan

1999-01-01

A series of new water-soluble bifunctional comonomers having both carboxyl and alkyl polyoxyethylene groups, such as sodium mono(ethyl polyoxyethylene) maleate (ZE series) with various molecular weights of polyoxyethylene ethyl ether, were synthesized and characterized. The effects of the structural factor, the amount and feeding mode of the comonomers, the initiator concentration and polymerization temperature on the stability of emulsifier-free emulsion copolymerization of methyl methacrylate (MMA) and butyl acrylate (BA) in the presence of a small amount of ZE with potassium persulfate as initiator were investigated. Stable, almost monodispersed MMA/BA/ZE emulsifier-free latex particles were prepared.

Preparation of Fe3O4/poly(styrene-butyl acrylate-[2-(methacryloxy)ethyl]trimethylammonium chloride) by emulsifier-free emulsion polymerization and its interaction with DNA

International Nuclear Information System (INIS)

Li Xiaolong; Liu Guoqiang; Yan Wei; Chu, Paul K.; Yeung, Kelvin W.K.; Wu Shuilin; Yi Changfeng; Xu Zushun

2012-01-01

Cationic magnetic polymer particles Fe 3 O 4 /poly(styrene-butyl acrylate-[2-(methacryloxy)ethyl]trimethylammonium chloride), a type of potential gene carrier, were prepared by emulsifier-free emulsion polymerization with oleic acid modified magnetite Fe 3 O 4 , styrene, butyl acrylate and [2-(methacryloxy)ethyl]trimethylammonium chloride) (METAC). The morphology of the particles was characterized by transmission electron microscopy and the composites of particles were characterized by FT-IR spectroscopy, X-ray diffraction. These results showed that magnetic particles were well dispersed in polymers with the content of about 15%(wt/wt). The composites exhibited superparamagnetism and possessed a certain level of magnetic response. The interactions between the particles with calf-thymus DNA (ct DNA) were confirmed by zeta potential measurement, UV–vis spectroscopy and fluorescence spectroscopy. The DNA-binding capacity determined by the agarose gel electrophoresis showed good binding capacity of the emulsion to DNA. These results suggested the potential of the cationic magnetic polymer emulsion as gene target delivery carrier. - Highlights: ► A new type of cationic magnetic polymer particles was synthesized by emulsifier-free emulsion polymerization. ► Structural, morphological, and magnetic properties of the composite were evaluated. ► The interaction between cationic magnetic polymer particles with DNA was confirmed by zeta potential measurements. ► UV–vis spectrophotometry, fluorescent spectroscopy and agarose gel electrophoresis. ► This process may have potential applications to gene carrier and DNA separation.

Synthesis and characterization of waterborne polyurethane acrylate copolymers

International Nuclear Information System (INIS)

Sultan, Misbah; Bhatti, Haq Nawaz; Zuber, Mohammad; Barikani, Mehdi

2013-01-01

Polyurethane acrylate copolymers were synthesized by emulsion polymerization process. To reduce the environmental hazards, organic solvents were replaced by eco-friendly aqueous system. Concentration of polyurethane and acrylate monomer was varied to investigate the effect of chemical composition on performance properties of copolymers. FTIR spectroscopy was used as a key tool to record the chemical synthesis route. The synthesized copolymer emulsions were characterized by evaluating their particle size, viscosity, dry weight content, chemical and water resistance. Thermal decomposition was studied by thermogravimetric analysis. Scanning electron microscope was used to visualize the morphological structure of copolymers. The experimental results indicate better polyurethane acrylate compatibility till the ratio of 30/70. However, these copolymers exhibited synergistic effects between the two polymers and revealed a remarkable improvement in numerous coating properties

The Emulsion Polymerization of Each of Vinyl Acetate and Butyl Acrylate Monomers Using bis (2-ethylhexyl) Maleate for Improving the Physicomechanical Properties of Paints and Adhesive Films

International Nuclear Information System (INIS)

Shaffei, K.A.; Moustafa, A.B.; Hamed, A.I.

2009-01-01

Improving the water sensitivity of polyvinyl acetate PVAc films as well as pressure sensitivity, adhesion and washability of poly butyl acrylate were achieved by using bis (2-ethylhexyl) maleate (BEHM). The emulsion polymerization kinetics of vinyl acetate and butyl acrylate in presence of BEHM was studied. The order of the polymerization reaction with respect to the BEHM in presence of each of vinyl acetate and butyl acrylate was studied. The physicomechanical properties of the polyvinyl acetate films and vinyl acetate-butyl acrylate copolymer films were studied in presence of BEHM and the obtained results were matched with those prepared in the presence of pluronic F 108 and showed superior values. The obtained mean average molecular weights were found to be smaller in presence of BEHM assuring the presence of chain transfer reaction.

The Emulsion Polymerization of Each of Vinyl Acetate and Butyl Acrylate Monomers Using bis (2-ethylhexyl Maleate for Improving the Physicomechanical Properties of Paints and Adhesive Films

Directory of Open Access Journals (Sweden)

K. A. Shaffei

2009-01-01

Full Text Available Improving the water sensitivity of polyvinyl acetate PVAc films as well as pressure sensitivity, adhesion and washability of polybutyl acrylate were achieved by using bis (2-ethylhexyl maleate (BEHM. The emulsion polymerization kinetics of vinyl acetate and butyl acrylate in presence of BEHM was studied. The order of the polymerization reaction with respect to the BEHM in presence of each of vinyl acetate and butyl acrylate was studied. The physicomechanical properties of the polyvinyl acetate films and vinyl acetate-butyl acrylate copolymer films were studied in presence of BEHM and the obtained results were matched with those prepared in the presence of pluronic F 108 and showed superior values. The obtained mean average molecular weights were found to be smaller in presence of BEHM assuring the presence of chain transfer reaction.

Strippable core-shell polymer emulsion for decontamination of radioactive surface contamination

International Nuclear Information System (INIS)

Hwang, Ho-Sang; Seo, Bum-Kyoung; Lee, Kune-Woo

2011-01-01

In this study, the core-shell composite polymer for decontamination from the surface contamination was synthesized by the method of emulsion polymerization and blends of polymers. The strippable polymer emulsion is composed of the poly(styrene-ethyl acrylate) [poly(St-EA)] composite polymer, poly(vinyl alcohol) (PVA) and polyvinylpyrrolidone (PVP). The morphology of the poly(St-EA) composite emulsion particle was core-shell structure, with polystyrene (PS) as the core and poly(ethyl acrylate) (PEA) as the shell. Core-shell polymers of styrene (St)/ethyl acrylate (EA) pair were prepared by sequential emulsion polymerization in the presence of sodium dodecyl sulfate (SDS) as an emulsifier using ammonium persulfate (APS) as an initiator. Related tests and analysis confirmed the success in synthesis of composite polymer. The products are characterized by FT-IR spectroscopy, TGA that were used, respectively, to show the structure, the thermal stability of the prepared polymer. Two-phase particles with a core-shell structure were obtained in experiments where the estimated glass transition temperature and the morphologies of emulsion particles. Decontamination factors of the strippable polymeric emulsion were evaluated with the polymer blend contents. (author)

Synthesis of porous poly(styrene-co-acrylic acid) microspheres through one-step soap-free emulsion polymerization: whys and wherefores.

Science.gov (United States)

Yan, Rui; Zhang, Yaoyao; Wang, Xiaohui; Xu, Jianxiong; Wang, Da; Zhang, Wangqing

2012-02-15

Synthesis of porous poly(styrene-co-acrylic acid) (PS-co-PAA) microspheres through one-step soap-free emulsion polymerization is reported. Various porous PS-co-PAA microspheres with the particle size ranging from 150 to 240 nm and with the pore size ranging from 4 to 25 nm are fabricated. The porous structure of the microspheres is confirmed by the transmission electron microscopy measurement and Brunauer-Emmett-Teller (BET) analysis. The reason for synthesis of the porous PS-co-PAA microspheres is discussed, and the phase separation between the encapsulated hydrophilic poly(acrylic acid) segment and the hydrophobic polystyrene domain within the PS-co-PAA microspheres is ascribed to the pore formation. The present synthesis of the porous PS-co-PAA microspheres is anticipated to be a new and convenient way to fabricate porous polymeric particles. Copyright © 2011 Elsevier Inc. All rights reserved.

Emulsion templated scaffolds with tunable mechanical properties for bone tissue engineering.

Science.gov (United States)

Owen, Robert; Sherborne, Colin; Paterson, Thomas; Green, Nicola H; Reilly, Gwendolen C; Claeyssens, Frederik

2016-02-01

Polymerised High Internal Phase Emulsions (PolyHIPEs) are manufactured via emulsion templating and exhibit a highly interconnected microporosity. These materials are commonly used as thin membranes for 3D cell culture. This study uses emulsion templating in combination with microstereolithography to fabricate PolyHIPE scaffolds with a tightly controlled and reproducible architecture. This combination of methods produces hierarchical structures, where the microstructural properties can be independently controlled from the scaffold macrostructure. PolyHIPEs were fabricated with varying ratios of two acrylate monomers (2-ethylhexyl acrylate (EHA) and isobornyl acrylate (IBOA)) and varying nominal porosity to tune mechanical properties. Young's modulus, ultimate tensile stress (UTS) and elongation at failure were determined for twenty EHA/IBOA compositions. Moduli ranged from 63.01±9.13 to 0.36±0.04MPa, UTS from 2.03±0.33 to 0.11±0.01MPa and failure strain from 21.86±2.87% to 2.60±0.61%. Selected compositions were fabricated into macro-porous woodpile structures, plasma treated with air or acrylic acid and seeded with human embryonic stem-cell derived mesenchymal progenitor cells (hES-MPs). Confocal and two-photon microscopy confirmed cell proliferation and penetration into the micro- and macro-porous architecture. The scaffolds supported osteogenic differentiation of mesenchymal cells and interestingly, the stiffest IBOA-based scaffolds that were plasma treated with acrylic acid promoted osteogenesis more strongly than the other scaffolds. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Synthesis and characterization of poly (n-butyl acrylate)-poly (methyl methacrylate) latex interpenetrating polymer networks by radiation-induced seeded emulsion polymerization

Energy Technology Data Exchange (ETDEWEB)

Yu Haibo [Department of Applied Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 (China); Peng Jing [Department of Applied Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 (China)], E-mail: jpeng@pku.edu.cn; Zhai Maolin; Li Jiuqiang; Wei Genshuan [Department of Applied Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 (China); Qiao Jinliang [Department of Applied Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 (China); SINOPEC Beijing Research Institute of Chemical Industry, Beijing 100013 (China)

2007-11-15

A series of latex interpenetrating polymer networks (LIPNs) were prepared via a two-stage emulsion polymerization of methyl methacrylate (MMA) or mixture of MMA and n-butyl acrylate (n-BA) on crosslinked poly(n-butyl acrylate)(PBA) seed latex using {sup 60}Co {gamma}-ray radiation. The particles of resultant latex were produced with diameters between 150 and 250 nm. FTIR spectra identified the formation of crosslinked copolymers of PMMA or P(MMA-co-BA). Dynamic light scattering (DLS) showed that with increasing n-BA concentration in second-stage monomers, the particle size of LIPN increased. Transmission electron microscope(TEM) photographs showed that the morphology of resultant acrylate interpenetrating polymer network (IPN) latex varied from the distinct core-shell structure to homogenous particle structure with the increase of n-BA concentration, and the morphology was mainly controlled by the miscibility between crosslinked PBA seed and second-stage copolymers and polarity of P(MMA-co-BA)copolymers. In addition, differential scanning calorimeter (DSC) measurements indicated the existence of reinforced miscibility between PBA seed and P(MMA-co-BA)copolymer in prepared LIPNs.

Acoustic Performance of Resilient Materials Using Acrylic Polymer Emulsion Resin.

Science.gov (United States)

Kim, Haseog; Park, Sangki; Lee, Seahyun

2016-07-19

There have been frequent cases of civil complaints and disputes in relation to floor impact noises over the years. To solve these issues, a substantial amount of sound resilient material is installed between the concrete slab and the foamed concrete during construction. A new place-type resilient material is made from cement, silica powder, sodium sulfate, expanded-polystyrene, anhydrite, fly ash, and acrylic polymer emulsion resin. Its physical characteristics such as density, compressive strength, dynamic stiffness, and remanent strain are analyzed to assess the acoustic performance of the material. The experimental results showed the density and the dynamic stiffness of the proposed resilient material is increased with proportional to the use of cement and silica powder due to the high contents of the raw materials. The remanent strain, related to the serviceability of a structure, is found to be inversely proportional to the density and strength. The amount of reduction in the heavyweight impact noise is significant in a material with high density, high strength, and low remanent strain. Finally, specimen no. R4, having the reduction level of 3 dB for impact ball and 1 dB for bang machine in the single number quantity level, respectively, is the best product to obtain overall acoustic performance.

Acoustic Performance of Resilient Materials Using Acrylic Polymer Emulsion Resin

Directory of Open Access Journals (Sweden)

Haseog Kim

2016-07-01

Full Text Available There have been frequent cases of civil complaints and disputes in relation to floor impact noises over the years. To solve these issues, a substantial amount of sound resilient material is installed between the concrete slab and the foamed concrete during construction. A new place-type resilient material is made from cement, silica powder, sodium sulfate, expanded-polystyrene, anhydrite, fly ash, and acrylic polymer emulsion resin. Its physical characteristics such as density, compressive strength, dynamic stiffness, and remanent strain are analyzed to assess the acoustic performance of the material. The experimental results showed the density and the dynamic stiffness of the proposed resilient material is increased with proportional to the use of cement and silica powder due to the high contents of the raw materials. The remanent strain, related to the serviceability of a structure, is found to be inversely proportional to the density and strength. The amount of reduction in the heavyweight impact noise is significant in a material with high density, high strength, and low remanent strain. Finally, specimen no. R4, having the reduction level of 3 dB for impact ball and 1 dB for bang machine in the single number quantity level, respectively, is the best product to obtain overall acoustic performance.

Engineered Multifunctional Fluorinated Film Based on Semicontinuous Emulsion Polymerization Using Polymerizable Quaternary Ammonium Emulsifiers

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Hongzhu Liu

2018-01-01

Full Text Available Along with society’s progress, high-quality coatings are widely used. Although fluorinated polymers were successfully prepared by semicontinuous emulsion polymerization with surfactants, chlorotrifluoroethylene (CTFE, and acrylate monomers, the optimization collocation of surfactants still has room for improvement. The traditional emulsifiers are physically absorbed onto the surface of latex particles. The latex film generated by latex particles is unstable in water, which limits its application. Herein, a novel series of cationic quaternary ammonium polymerizable surfactant was selected because it can react with CTFE and acrylate monomers and can become a part of the polymers. We also studied the effects of emulsifier type on resultant emulsion properties. In addition, wonderful weatherability, water resistance, and antibacterial and antifouling of the multifunctional fluorinated films were observed, which would open up a bright future for coating industries.

Synthesis and Characterization of Encapsulated Nanosilica Particles with an Acrylic Copolymer by in Situ Emulsion Polymerization Using Thermoresponsive Nonionic Surfactant

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Daryoosh Vashaee

2013-08-01

Full Text Available Nanocomposites of encapsulated silica nanoparticles were prepared by in situ emulsion polymerization of acrylate monomers. The synthesized material showed good uniformity and dispersion of the inorganic components in the base polymer, which enhances the properties of the nanocomposite material. A nonionic surfactant with lower critical solution temperature (LCST was used to encapsulate the silica nanoparticles in the acrylic copolymer matrix. This in situ method combined the surface modification and the encapsulation in a single pot, which greatly simplified the process compared with other conventional methods requiring separate processing steps. The morphology of the encapsulated nanosilica particles was investigated by dynamic light scattering (DLS and transmission electron microscopy (TEM, which confirmed the uniform distribution of the nanoparticles without any agglomerations. A neat copolymer was also prepared as a control sample. Both the neat copolymer and the prepared nanocomposite were characterized by Fourier transform infrared spectroscopy (FTIR, thermal gravimetric analyses (TGA, dynamic mechanical thermal analysis (DMTA and the flame resistance test. Due to the uniform dispersion of the non-agglomerated nanoparticles in the matrix of the polymer, TGA and flame resistance test results showed remarkably improved thermal stability. Furthermore, DMTA results demonstrated an enhanced storage modulus of the nanocomposite samples compared with that of the neat copolymer, indicating its superior mechanical properties.

Preparation of Fe{sub 3}O{sub 4}/poly(styrene-butyl acrylate-[2-(methacryloxy)ethyl]trimethylammonium chloride) by emulsifier-free emulsion polymerization and its interaction with DNA

Energy Technology Data Exchange (ETDEWEB)

Li Xiaolong; Liu Guoqiang; Yan Wei [Ministry-of-Education Key Laboratory for the Green Preparation and Application of Functional Materials, Hubei University, Wuhan (China); Chu, Paul K. [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon (Hong Kong); Yeung, Kelvin W.K. [Division of Spine Surgery, Department of Orthopaedics and Traumatology, The University of Hong Kong, Pokfulam (Hong Kong); Wu Shuilin; Yi Changfeng [Ministry-of-Education Key Laboratory for the Green Preparation and Application of Functional Materials, Hubei University, Wuhan (China); Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon (Hong Kong); Division of Spine Surgery, Department of Orthopaedics and Traumatology, The University of Hong Kong, Pokfulam (Hong Kong); Xu Zushun, E-mail: zushun25@yahoo.com.cn [Ministry-of-Education Key Laboratory for the Green Preparation and Application of Functional Materials, Hubei University, Wuhan (China); Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon (Hong Kong); Division of Spine Surgery, Department of Orthopaedics and Traumatology, University of Hong Kong, Pokfulam (Hong Kong)

2012-04-15

Cationic magnetic polymer particles Fe{sub 3}O{sub 4}/poly(styrene-butyl acrylate-[2-(methacryloxy)ethyl]trimethylammonium chloride), a type of potential gene carrier, were prepared by emulsifier-free emulsion polymerization with oleic acid modified magnetite Fe{sub 3}O{sub 4}, styrene, butyl acrylate and [2-(methacryloxy)ethyl]trimethylammonium chloride) (METAC). The morphology of the particles was characterized by transmission electron microscopy and the composites of particles were characterized by FT-IR spectroscopy, X-ray diffraction. These results showed that magnetic particles were well dispersed in polymers with the content of about 15%(wt/wt). The composites exhibited superparamagnetism and possessed a certain level of magnetic response. The interactions between the particles with calf-thymus DNA (ct DNA) were confirmed by zeta potential measurement, UV-vis spectroscopy and fluorescence spectroscopy. The DNA-binding capacity determined by the agarose gel electrophoresis showed good binding capacity of the emulsion to DNA. These results suggested the potential of the cationic magnetic polymer emulsion as gene target delivery carrier. - Highlights: Black-Right-Pointing-Pointer A new type of cationic magnetic polymer particles was synthesized by emulsifier-free emulsion polymerization. Black-Right-Pointing-Pointer Structural, morphological, and magnetic properties of the composite were evaluated. Black-Right-Pointing-Pointer The interaction between cationic magnetic polymer particles with DNA was confirmed by zeta potential measurements. Black-Right-Pointing-Pointer UV-vis spectrophotometry, fluorescent spectroscopy and agarose gel electrophoresis. Black-Right-Pointing-Pointer This process may have potential applications to gene carrier and DNA separation.

Preparation of Paraffin@Poly(styrene-co-acrylic acid) Phase Change Nanocapsules via Combined Miniemulsion/Emulsion Polymerization.

Science.gov (United States)

Zhang, Feng; Liu, Tian-Yu; Hou, Gui-Hua; Guan, Rong-Feng; Zhang, Jun-Hao

2018-06-01

The fast development of solid-liquid phase change materials calls for nanomaterials with large specific surface area for rapid heat transfer and encapsulation of phase change materials to prevent potential leakage. Here we report a combined miniemulsion/emulsion polymerization method to prepare poly(styrene-co-acrylic acid)-encapsulated paraffin (paraffin@P(St-co-AA)) nanocapsules. The method could suppress the shortcomings of common miniemulsion polymerization (such as evaporation of monomer and decomposition of initiator during ultrasonication). The paraffin@P(St-co-AA) nanocapsules are uniform in size and the polymer shell can be controlled by the weight ratio of St to paraffin. The phase change behavior of the nanocapsules is similar to that of pure paraffin. We believe our method can also be utilized to synthesize other core-shell phase change materials.

Radiation vulcanization of natural rubber latex using irradiation n-butyl acrylate aqueous emulsion as sensitizer

International Nuclear Information System (INIS)

Vo Van Thien; Nguyen Quoc Hien; Keizo Makuuchi; Fumio Yoshii

2000-01-01

Natural rubber latex was vulcanized by gamma radiation with n-butyl acrylate aqueous emulsion irradiated at dose of 1.5 kGy as sensitizer. The total solid content of latex increases on the irradiation dose. The viscosity of latex on the standing time was investigated and became stable after one month of storage. The gel content of latex films increasing with irradiation dose and attained more than 94% at dose of 10 kGy. Tensile strength of films reached the values of 31MPa; 30 Mpa and 25 Mpa at vulcanization doses of 20 kGy, 15 kGy and 8 kGy for the concentrations of sensitizer 7 phr, 9 phr and 13 phr respectively. Elongation at break decreases as increasing dose. Tear strength of rubber films was from 30-40 N/mm. The tackiness of latex films decreases and smell of vulcanized latex is almost negligible. (author)

Polyurethane acrylate networks including cellulose nanocrystals: a comparison between UV and EB- curing

International Nuclear Information System (INIS)

Furtak-Wrona, K.; Kozik-Ostrówka, P.; Jadwiszczak, K.; Maigret, J.E.; Aguié-Béghin, V.; Coqueret, X.

2018-01-01

A water-based polyurethane (PUR) acrylate water emulsion was selected as a radiation curable matrix for preparing nanocomposites including cellulose nanocrystals (CNC) prepared by controlled hydrolysis of Ramie fibers. Cross-linking polymerization of samples prepared in the form of films or of 1 mm-thick bars was either initiated by exposure to the 395 nm light of a high intensity LED lamp or by treatment with low energy electron beam (EB). The conversion level of acrylate functions in samples submitted to increasing radiation doses was monitored by Fourier Transform Infrared Spectroscopy (FTIR). Differential Scanning Calorimetry (DSC) and Dynamic Mechanical Analysis (DMA) were used to characterize changes in the glass transition temperature of the PUR-CNC nanocomposites as a function of acrylate conversion and of CNC content. Micromechanical testing indicates the positive effect of 1 wt% CNC on Young's modulus and on the tensile strength at break (σ) of cured nanocomposites. The presence of CNC in the PUR acrylate matrix was shown to double the σ value of the nanocomposite cured to an acrylate conversion level of 85% by treatment with a 25 kGy dose under EB, whereas no increase of σ was observed in UV-cured samples exhibiting the same acrylate conversion level. The occurrence of grafting reactions inducing covalent linkages between the polysaccharide nanofiller and the PUR acrylate matrix during the EB treatment is advanced as an explanation to account for the improvement observed in samples cured under ionizing radiation. - Highlights: • Nanocomposites were prepared from o/w PUR acrylate emulsion and CNC suspension. • Nanocomposite and reference materials were cured to the same conversion by UV or EB. • Introducing 1 wt% CNC in EB-cured composites doubles the tensile strength. • UV-cured nanocomposites did not show significant improvement in tensile strength.

TiO2 supported over porous silica photocatalysts for pesticide degradation using solar light: Part 2. Silica prepared using acrylic acid emulsion

International Nuclear Information System (INIS)

Phanikrishna Sharma, Mangalampalli V.; Durga Kumari, Valluri; Subrahmanyam, Machiraju

2010-01-01

An acrylic acid emulsion mixture is used for synthesis of novel porous silica (E-Si) material. The photocatalytic activity of TiO 2 under solar light irradiation for isoproturon (herbicide) degradation is drastically increased when dispersed over E-Si support using solid state dispersion (SSD) technique. The composite material is characterized by XRD, nitrogen adsorption-desorption isotherms, UV-vis DRS, SEM and TEM measurements. The photocatalytic activities of the composite catalysts are evaluated for different parameters. The 5 wt% TiO 2 /E-Si is found to be highly active for isoproturon degradation.

Modeling of emulsion copolymer microstructure

NARCIS (Netherlands)

van Doremaele, G.H.J.; Herk, van A.M.; German, A.L.

1992-01-01

A model is developed to describe stages II and III of batch emulsion copolymn., and its predictive capabilities are investigated by application to the system styrene-Me acrylate. The main reaction site is the monomer-swollen polymer particle. Copolymn. rate and copolymer microstructure (molar

A Potentiometric Formaldehyde Biosensor Based on Immobilization of Alcohol Oxidase on Acryloxysuccinimide-modified Acrylic Microspheres

Directory of Open Access Journals (Sweden)

Lee Yook Heng

2010-11-01

Full Text Available A new alcohol oxidase (AOX enzyme-based formaldehyde biosensor based on acrylic microspheres has been developed. Hydrophobic poly(n-butyl acrylate-N-acryloxy-succinimide [poly(nBA-NAS] microspheres, an enzyme immobilization matrix, was synthesized using photopolymerization in an emulsion form. AOX-poly(nBA-NAS microspheres were deposited on a pH transducer made from a layer of photocured and self-plasticized polyacrylate membrane with an entrapped pH ionophore coated on a Ag/AgCl screen printed electrode (SPE. Oxidation of formaldehyde by the immobilized AOX resulted in the production of protons, which can be determined via the pH transducer. Effects of buffer concentrations, pH and different amount of immobilization matrix towards the biosensor’s analytical performance were investigated. The formaldehyde biosensor exhibited a dynamic linear response range to formaldehyde from 0.3–316.2 mM and a sensitivity of 59.41 ± 0.66 mV/decade (R2 = 0.9776, n = 3. The lower detection limit of the biosensor was 0.3 mM, while reproducibility and repeatability were 3.16% RSD (relative standard deviation and 1.11% RSD, respectively (n = 3. The use of acrylic microspheres in the potentiometric formaldehyde biosensor improved the biosensor’s performance in terms of response time, linear response range and long term stability when compared with thick film immobilization methods.

TiO{sub 2} supported over porous silica photocatalysts for pesticide degradation using solar light: Part 2. Silica prepared using acrylic acid emulsion

Energy Technology Data Exchange (ETDEWEB)

Phanikrishna Sharma, Mangalampalli V.; Durga Kumari, Valluri [Inorganic and Physical Chemistry Division, Indian Institute of Chemical Technology, Tarnaka, Hyderabad 500607, Andhra Pradesh (India); Subrahmanyam, Machiraju, E-mail: subrahmanyam@iict.res.in [Inorganic and Physical Chemistry Division, Indian Institute of Chemical Technology, Tarnaka, Hyderabad 500607, Andhra Pradesh (India)

2010-03-15

An acrylic acid emulsion mixture is used for synthesis of novel porous silica (E-Si) material. The photocatalytic activity of TiO{sub 2} under solar light irradiation for isoproturon (herbicide) degradation is drastically increased when dispersed over E-Si support using solid state dispersion (SSD) technique. The composite material is characterized by XRD, nitrogen adsorption-desorption isotherms, UV-vis DRS, SEM and TEM measurements. The photocatalytic activities of the composite catalysts are evaluated for different parameters. The 5 wt% TiO{sub 2}/E-Si is found to be highly active for isoproturon degradation.

Palm oil based polyols for acrylated polyurethane production

International Nuclear Information System (INIS)

Rida Tajau; Mohd Hilmi Mahmood; Mek Zah Salleh; Khairul Zaman Mohd Dahlan; Rosley Che Ismail

2006-01-01

Palm oil becomes important renewable resources for the production of polyols for the polyurethane manufacturing industry. The main raw materials used for the production of acrylated polyurethane are polyols, isocyanates and hydroxyl terminated acrylate compounds. In these studies, polyurethane based natural polymer (palm oil), i.e., POBUA (Palm Oil Based Urethane Acrylate) were prepared from three different types of palm oil based polyols i.e., epoxidised palm oil (EPOP), palm oil oleic acid and refined, bleached and deodorized (RBD) palm olein based polyols. The performances of these three acrylated polyurethanes when used for coatings and adhesives were determined and compared with each other. (Author)

Monitoring emulsion homopolymerization reactions using FT-Raman spectroscopy

Directory of Open Access Journals (Sweden)

M. M. Reis

2005-03-01

Full Text Available The present work describes a methodology for estimation of monomer concentration during homopolymerization reactions by Raman spectroscopy. The estimation is done using linear models based on two different approaches: a univariate approach and a multivariate approach (with principal component regression, PCR, or partial least squares regression, PLS. The linear models are fitted with data from spectra collected from synthetic samples, i.e., samples prepared by dispersing a known concentration of monomer in polymer emulsions. Homopolymerizations of butyl acrylate and of vinyl acetate were monitored by collecting samples from the reactor, and results show that the methodology is efficient for the model fitting and that Raman spectroscopy is a promising technique for on-line monitoring of the emulsion polymerization process.

Oil-Acrylic hybrid latexes as binders for waterborne coatings

NARCIS (Netherlands)

Hamersveld, E.M.S.; Es, van J.J.G.S.; German, A.L.; Cuperus, F.P.; Weissenborn, P.; Hellgren, A.C.

1999-01-01

The combination of the characteristics of oil, or alkyd, emulsions and acrylic latexes in a waterborne binder has been the object of various studies in the past. Strategies for combining the positive properties of alkyds, e.g. autoxidative curing, gloss and penetration in wood, with the fast drying

Oil-acrylic hybrid latexes as binders for waterborne coatings

NARCIS (Netherlands)

Hamersveld, van E.M.S.; Es, van J.; German, A.L.; Cuperus, F.P.; Weissenborn, P.; Hellgren, A.C.

1999-01-01

The combination of the characteristics of oil, or alkyd, emulsions and acrylic latexes in a waterborne binder has been the object of various studies in the past. Strategies for combining the positive properties of alkyds, e.g. autoxidative curing, gloss and penetration in wood, with the fast drying

Preparation of nanoparticles from acrylated palm oil microemulsion using radiation technique

International Nuclear Information System (INIS)

Rida Tajau; Wan Mohd Zin Wan Yunus; Khairul Zaman Mohd Dahlan; Mohd Hilmi Mahmood; Kamaruddin Hashim; Mohd Yusof Hamzah

2011-01-01

The use of microemulsion in the development of nanoparticle based on acrylated palm oil product is demonstrated. Acrylated palm oil microemulsions were prepared using ionic surfactant. Combination methods of emulsion polymerization and radiation crosslinking were applied to the microemulsion system for synthesizing nanoparticle. The ionizing radiation technique was introduced to generate a crosslinking reaction in the development of nanoparticle. The nanoparticle was evaluated in terms of particle diameter, surface charge, pH and conductance. Their image was captured using Transmission electron microscopy (TEM). Results show that the size, charge and shape of the particles are influenced by concentration of surfactants, monomer concentration, radiation dose and time of storage. The study showed a promising method to produced nanoparticle. This nano-sized product has the potential to be utilized as controlled-drug-release-carrier. (Author)

Wettability modification of rock cores by fluorinated copolymer emulsion for the enhancement of gas and oil recovery

Energy Technology Data Exchange (ETDEWEB)

Feng Chunyan [State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao 266555 (China); Kong Ying, E-mail: yingkong1967@yahoo.com.cn [State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao 266555 (China); Jiang Guancheng [MOE Key Laboratory of Petroleum Engineering, China University of Petroleum, Beijing 102249 (China); Yang Jinrong; Pu Chunsheng [State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao 266555 (China); Zhang Yuzhong [Key Lab of Hollow Fibre Membrane Materials and Membrane Process, Tianjin Polytechnic University, Tianjin 300160 (China)

2012-07-01

The fluorine-containing acrylate copolymer emulsion was prepared with butyl acrylate, methacrylic acid and 1H, 1H, 2H, 2H-perfluorooctyl acrylate as monomers. Moreover, the structure of the copolymer was verified by Fourier transform infrared (FTIR), nuclear magnetic resonance ({sup 1}H NMR and {sup 19}F NMR) and X-ray photoelectron spectroscopy (XPS) analyses. The results showed that all the monomers had been copolymerized and the presence of fluorine moieties. The contact angle (CA) analyses, capillary rise and imbibition spontaneous tests were used to estimate the influence of the copolymer emulsion on the wettability of gas reservoirs. It was observed that the rock surface was of large contact angles of water, oilfield sewage, hexadecane and crude oil after treatment with the emulsion. The capillary rise results indicated that the contact angles of water/air and oil/air systems increased from 60 Degree-Sign and 32 Degree-Sign to 121 Degree-Sign and 80 Degree-Sign , respectively, due to the emulsion treatment. Similarly, because of wettability alteration by the fluoropolymer, the imbibition of water and oil in rock core decreased significantly. Experimental results demonstrated that the copolymer emulsion can alter the wettability of porous media from strong liquid-wetting to gas-wetting. This work provides a cost-effective method to prepare the fluoropolymer which can increase gas deliverability by altering the wettability of gas-condensate reservoirs and mitigating the water block effect.

Enhancing saltiness in emulsion based foods

Directory of Open Access Journals (Sweden)

Lad Mita

2012-07-01

Full Text Available Abstract Background The concept of enhancing saltiness perception in emulsions and a liquid food formulated with the emulsions (ambient vegetable soup through increasing salt concentration in the continuous phase while retaining the fat content of the (aqueous continuous product was evaluated. This was accomplished by increasing the droplet phase volume using duplex emulsion technology. Viscosity and droplet size distribution was measured. Saltiness evaluation was based on simple paired comparison testing (2-Alternate Forced Choice tests, BS ISO 5495:2007. Results Single and duplex emulsions and emulsion-based products had comparable mean oil droplet diameters (25 to 30 μm; however, viscosity of the duplex emulsion systems was considerably higher. Sensory assessment of saltiness of emulsion pairs (2AFC indicated duplex technology enhanced saltiness perception compared to a single emulsion product at the same salt content (6.3 g/100 g in both simple emulsions and the formulated food product (P = 0.0596 and 0.0004 respectively although assessors noted the increased viscosity of the duplex systems. The formulated food product also contained pea starch particles which may have aided product mixing with saliva and thus accelerated tastant transport to the taste buds. Lowering salt content in the duplex systems (to levels of aqueous phase salt concentration similar to the level in the single systems resulted in duplex systems being perceived as less salty than the single system. It appears that the higher viscosity of the duplex systems could not be “overruled” by enhanced mixing through increased droplet phase volume at lowered salt content. Conclusions The results showed that salt reduction may be possible despite the added technology of duplex systems increasing the overall measured viscosity of the product. The changes in viscosity behavior impact mouthfeel, which may be exploitable in addition to the contribution towards salt

Polyurethane acrylate networks including cellulose nanocrystals: a comparison between UV and EB- curing

Science.gov (United States)

Furtak-Wrona, K.; Kozik-Ostrówka, P.; Jadwiszczak, K.; Maigret, J. E.; Aguié-Béghin, V.; Coqueret, X.

2018-01-01

A water-based polyurethane (PUR) acrylate water emulsion was selected as a radiation curable matrix for preparing nanocomposites including cellulose nanocrystals (CNC) prepared by controlled hydrolysis of Ramie fibers. Cross-linking polymerization of samples prepared in the form of films or of 1 mm-thick bars was either initiated by exposure to the 395 nm light of a high intensity LED lamp or by treatment with low energy electron beam (EB). The conversion level of acrylate functions in samples submitted to increasing radiation doses was monitored by Fourier Transform Infrared Spectroscopy (FTIR). Differential Scanning Calorimetry (DSC) and Dynamic Mechanical Analysis (DMA) were used to characterize changes in the glass transition temperature of the PUR-CNC nanocomposites as a function of acrylate conversion and of CNC content. Micromechanical testing indicates the positive effect of 1 wt% CNC on Young's modulus and on the tensile strength at break (σ) of cured nanocomposites. The presence of CNC in the PUR acrylate matrix was shown to double the σ value of the nanocomposite cured to an acrylate conversion level of 85% by treatment with a 25 kGy dose under EB, whereas no increase of σ was observed in UV-cured samples exhibiting the same acrylate conversion level. The occurrence of grafting reactions inducing covalent linkages between the polysaccharide nanofiller and the PUR acrylate matrix during the EB treatment is advanced as an explanation to account for the improvement observed in samples cured under ionizing radiation.

Bond strength test of acrylic artificial teeth with prosthetic base

Directory of Open Access Journals (Sweden)

Erna Kurnikasari

2008-07-01

Full Text Available Denture consists of acrylic artificial teeth and acrylic prothesis base bond chemically with a bond strength of 315 kgF/cm2. Most of the commercial acrylic artificial teeth do not specify their specifications and all of those acrylic artificial teeth do not include mechanical data (bond strength. The aim of this study is to discover which acrylic artificial teeth meet ADA specification no. 15. This study is a descriptive analytic study performed to 5 acrylic artificial teeth posterior brands commonly used by dentists and technicians. From each brand, 3 sample teeth were taken. The acrylic artificial teeth were prepared into a rectangular shape and were attached between acrylic prothesis base simulation and jigs. The sample was given tensile load using a Universal Testing Machine. The amount of force that causes the teeth to be fractured was recorded and the bond strength was calculated. The results of the study show that the average value for the five acrylic artificial teeth for the five brands were as followed: Brand A, 125.993 kgF/cm2; B, 188.457 kgF/cm2; C, 175.880 kgF/cm2; D, 153.373 kgF/cm2; E, 82.839 kgF/cm2. The data can be tested statistically by using One Way ANOVA test and Dunnett test (alpha = 0.05. From the study, it is concluded that the five acrylic artificial teeth have a bond strength below the ADA specification no. 15.

Development of O/W emulsions containing Euterpe oleracea extract and evaluation of photoprotective efficacy

Directory of Open Access Journals (Sweden)

Cláudia Cecilio Daher

2014-09-01

Full Text Available Euterpe oleraceaMart. is a palm tree popularly known as açai, which is primarily found in northern Brazil. The açai's fruits contain anthocyanins, a class of polyphenols to which antioxidant properties have been attributed. The aim of this work was to develop O/W sunscreens emulsions containing açai glycolic extract (AGE and to evaluate both their physical stability and photoprotective efficacy. Emulsions containing AGE and sunscreens were formulated using different types and concentrations of polymeric surfactant (acrylates/C 10-30 alkyl acrylate crosspolymer and sodium polyacrylate. The influence of two rheology modifiers (polyacrylamide (and C13-14/isoparaffin (and Laureth-7 and Carbomer on the stability was also investigated. Physical stability was evaluated by preliminary and accelerated studies. Emulsions with 1.0% sodium polyacrylate were stable and exhibited non-newtonian pseudoplastic behavior and thixotropy. Photoprotective efficacy was evaluated by in vivo Sun Protection Factor (SPF and determination of Protection Factor of UVA (PF-UVA. When AGE was added to the sunscreen emulsion, no significant increase in the in vivo SPF value was observed. The emulsion containing AGE showed PF-UVA = 14.97, 1.69 of the SPF/PF-UVA ratio and a critical wavelength value of 378 nm, and may therefore be considered a sunscreen with UVA and UVB protection.

Simulation of emulsion copolymerization reactions in a continuous pulsed sieve-plate column reactor

OpenAIRE

C. Sayer; R. Giudici

2004-01-01

This work addressed the viability of using a pulsed sieve-plate column reactor to carry out continuous vinyl acetate/butyl acrylate emulsion copolymerization reactions. A rigorous mathematical model of emulsion copolymerization reactions in a tubular reactor with axial dispersion was used for this purpose. Operational conditions were defined to attain high monomer conversions at the reactor outlet in a relatively short residence time and, at the same time, produce a copolymer with a more homo...

Effect of ionizing radiation on properties of acrylic pressure sensitive adhesives

International Nuclear Information System (INIS)

Panta, P.P.; Zimek, Z.A.; Giuszewski, W.; Kowalewski, R.; Wojtynska, E.; Wnuk, A.

1998-01-01

Pressure-sensitive adhesives for technical application are widely produced. The biological properties of adhesives depend on the type of monomers used. The available literature data as experience of the authors of this study in the area of pressure-sensitive acrylic adhesive, polymers used in medicine, polymerisation in aqueous media, radiation sterilization, permit to make an assumption that it is possible to elaborate the technology of production of pressure-sensitive adhesives in aqueous emulsion for medical applications. Identification of phenomena influencing the adhesive properties, especially its adhesion, cohesion, tack and durability is of great importance. The control of polymer structure is performed by means of adequate selection of conditions of synthesis and parameters of radiation processing. The authors investigate the influence on the final products of such factors as the type and amount of monomers used, their mutual ratio, as well as the ratio monomers and the dose of ionising radiation. There is no available literature information concerning the investigation of resistance of acrylic emulsion adhesive to sterilisation by electron beam. It is known from unpublished research that some adhesives are resistant to radiation, while others undergo destruction. It probably depends on the composition of emulsion, specifically on the additives which modify adhesives. Simultaneous achievement of good cohesion and adhesion in the case of such types of pressure sensitive adhesives is very difficult pressure sensitive adhesives is very difficult

Studies on the effect of nano-TiO{sub 2} on vinyl acetate-butyl acrylate latex-based surface coating

Energy Technology Data Exchange (ETDEWEB)

Suma, K.K. [Dept. of Polymer Science and Rubber Technology, Cochin University of Science and Technology, Kochi 22, Kerala (India); Dept. of Chemistry, Maharaja' s College, Ernakulam, Kerala (India); Jacob, Sinto [Dept. of Polymer Science and Rubber Technology, Cochin University of Science and Technology, Kochi 22, Kerala (India); Joseph, Rani, E-mail: rani@cusat.ac.i [Dept. of Polymer Science and Rubber Technology, Cochin University of Science and Technology, Kochi 22, Kerala (India)

2010-04-15

Vinyl acetate-butyl acrylate (VAc-BuA) copolymer latex was prepared by emulsion polymerization. The polymerization conditions and the composition were optimized. The 85/15 wt.% (vinyl acetate/butyl acrylate) gave good tensile strength of the order of 15.6 MPa and a glass transition temperature (T{sub g}) value of -6.49 deg. C. This copolymer was used as a binder in the paint formulation. In this formulation nanosized TiO{sub 2} sol was used as a pigment instead of conventional rutile TiO{sub 2}. Nanosized TiO{sub 2} is prepared by wet process. These nanosized TiO{sub 2} rutile colloidal sol has improved properties such as photostability, UV shielding, dispersion stability, etc. The surface properties of paint were found to be superior compared to commercially used paint.

Kinetic advantages of using microwaves in the emulsion polymerization of MMA

Energy Technology Data Exchange (ETDEWEB)

Costa, C. [Departamento de Engenharia Quimica, Universidade Federal de Santa Catarina, Campus Universitario, CEP: 88040-900, Florianopolis, SC (Brazil); Santos, A.F.; Fortuny, M. [Programa de Mestrado em Engenharia de Processos, Universidade Tiradentes, Instituto de Tecnologia e Pesquisa, Av. Murilo Dantas, 300, CEP: 49032-490, Aracaju, SE (Brazil); Araujo, P.H.H. [Departamento de Engenharia Quimica, Universidade Federal de Santa Catarina, Campus Universitario, CEP: 88040-900, Florianopolis, SC (Brazil); Sayer, C. [Departamento de Engenharia Quimica, Universidade Federal de Santa Catarina, Campus Universitario, CEP: 88040-900, Florianopolis, SC (Brazil)], E-mail: csayer@enq.ufsc.br

2009-03-01

Microwave irradiation has been an interesting alternative for heating systems and several chemical reactions. In polymerization processes, microwaves can enhance reaction rates or improve specific characteristics of the formed polymer. In this work, the use of microwave irradiation in emulsion polymerization reactions has been studied, using a commercial microwave reactor, which is able to perform syntheses under controlled conditions of temperature and power. Methyl methacrylate emulsion polymerization reactions were faster, resulting in smaller polymer particles, in comparison to the conventional heating method (reactions in a jacketed reactor). Different effects were observed in the emulsion polymerization of butyl acrylate. To study the effect of high power microwave irradiation upon the emulsion polymerization, a pulsed irradiation strategy was developed, in which the samples were repeatedly heated within short intervals of time (about 27 s) at the maximum microwave power. A significant reduction of the total time of irradiation was observed in reactions carried out under the pulsed scheme, showing the kinetic advantages of using microwaves in emulsion polymerization processes.

Simulation of emulsion copolymerization reactions in a continuous pulsed sieve-plate column reactor

Directory of Open Access Journals (Sweden)

Sayer C.

2004-01-01

Full Text Available This work addressed the viability of using a pulsed sieve-plate column reactor to carry out continuous vinyl acetate/butyl acrylate emulsion copolymerization reactions. A rigorous mathematical model of emulsion copolymerization reactions in a tubular reactor with axial dispersion was used for this purpose. Operational conditions were defined to attain high monomer conversions at the reactor outlet in a relatively short residence time and, at the same time, produce a copolymer with a more homogeneous composition.

UV-crosslinkable photoreactive self-adhesive hydrogels based on acrylics

Directory of Open Access Journals (Sweden)

Czech Zbigniew

2016-06-01

Full Text Available Hydrogels are a unique class of macromolecular networks that can hold a large fraction of an aqueous solvent within their structure. They are suitable for biomedical area including controlled drug delivery and for technical applications as self-adhesive materials for bonding of wet surfaces. This paper describes photoreactive self-adhesive hydrogels based on acrylics crosslinked using UV radiation. They are prepared in ethyl acetate through radical polymerization of monomers mixture containing 2-ethylhexyl acrylate (2-EHA, butyl acrylate (BA, acrylic acid (AA and copolymerizable photoinitiator 4-acryloyloxy benzophenone (ABP at presence of radical starter 2.2’-azobis-diisobutyronitrile AIBN. The synthesized acrylic copolymers were determined by viscosity and GPC analysis and later modified using ethoxylated amines. 4-acryloyloxy benzophenone (ABP was used as crosslinking monomer. After UV crosslinking the properties of these novel synthesized hydrogels, such as tack, peel adhesion, shears strength, elongation and water adsorption were also studied.

Preparation and characterization of emulsifier-free polyphenylsilsesquioxane-poly (styrene–butyl acrylate) hybrid particles

Energy Technology Data Exchange (ETDEWEB)

Bai, Ruiqin; Qiu, Teng, E-mail: qiuteng@mail.buct.edu.cn; Han, Feng; He, Lifan; Li, Xiaoyu, E-mail: lixy@mail.buct.edu.cn

2013-10-01

The core–shell polyphenylsilsesquioxane-poly (styrene–butyl acrylate) hybrid latex paticles with polyphenylsilsesquioxane as core and poly (styrene–butyl acrylate) as shell were successfully synthesized by seeded emulsion polymerization using polyphenylsisesquioxane (PPSQ) latex particles as seeds. X-ray diffraction (XRD) indicated that the polyphenylsilsesquioxane (PPSQ) had ladder structure, and PPSQ had incorporated into the hybrid latex particles. Transmission electron microscopy (TEM) confirmed that the resultant hybrid latex particles had the core–shell structure. TEM and dynamic light scattering (DLS) analysis indicated that the polyphenylsisesquioxane latex particles and obtained core–shell hybrid latex particles were uniform and possessed narrow size distributions. X-ray photoelectron spectroscopy (XPS) analysis also indicated that the PPSQ core particles were enwrapped by the polymer shell. In addition, compared with pure poly (styrene–butyl acrylate) latex film, the polyphenylsilsesquioxane-poly (styrene–butyl acrylate) hybrid latex film exhibited lower water uptake, higher pencil hardness and better thermal stability.

Extraction of metal cations by polyterephthalamide microcapsules containing a poly(acrylic acid) gel.

Science.gov (United States)

Laguecir, A; Ernst, B; Frère, Y; Danicher, L; Burgard, M

2002-01-01

Polyterephthalamide microcapsules containing a poly(acrylic acid) gel as a macromolecular ligand (PAA-CAPS) were prepared using an original two step polymerization process in a water-in-oil inverse emulsion system. A polyamide microcapsule containing acrylic acid, initiator and cross-linking agent, is formed by interfacial polycondensation of terephthaloyl dichloride with hexamethylenediamine. In situ radical polymerization of the microcapsule core acrylic acid is initiated to obtain encapsulated poly(acrylic acid) gel. Reference polyamide microcapsules, i.e. without ligand (CAPS), were also synthesized. The mean diameter of synthesized microcapsules was 210 microm, and the microcapsule wall thickness was evaluated by SEM and TEM observations of microcapsule cross-section cuts. The microcapsule water content was determined by thermogravimetric experiments. The extractabilities of Cu(II), Ni(II), Co(II) and Zn(II) into PAA-CAPS were examined. The stripping of the various cations can be promoted in diluted hydrochloric acid solutions.

Structure- and oil type-based efficacy of emulsion adjuvants.

Science.gov (United States)

Jansen, Theo; Hofmans, Marij P M; Theelen, Marc J G; Manders, Frans; Schijns, Virgil E J C

2006-06-29

Oil-based emulsions are well-known immunopotentiators for inactivated, "killed" vaccines. We addressed the relationship between emulsion structure and levels of in vivo antibody formation to inactivated New Castle Disease virus (NDV) and Infectious Bronchitis virus (IBV) as antigens in 3-week-old chickens. The use of a polymeric emulsifier allowed for direct comparison of three types of emulsions, water-in-oil (W/O), oil-in-water (O/W) and W/O-in-water (W/O/W), while maintaining an identical content of components for each vehicle. They were prepared with either non-metabolizable, mineral oil or metabolizable, Miglyol 840. In addition, we assessed the inherent release capacity of each emulsion variant in vitro. Remarkably, we noted that W/O-type emulsions induced the best immune responses, while they released no antigen during 3 weeks. In general, mineral oil vaccines showed superior efficacy compared to Miglyol 840-based vaccines.

Minimum pressure for sustained combustion in AN-based emulsions

Energy Technology Data Exchange (ETDEWEB)

Goldthorp, S.; Turcotte, R.; Badeen, C.M. [Natural Resources Canada, Ottawa, ON (Canada). Canadian Explosives Research Laboratory; Chan, S.K. [Orica Canada Inc., Brownsburg-Chatham, PQ (Canada)

2008-04-15

AN-based emulsions have been involved in a relatively high number of accidental explosions related to pumping operations during their manufacture, transfer and handling. The minimum burning pressure (MBP) of emulsions is used to estimate safe operating pressures for pumping and mixing equipment. This study examined testing protocols conducted to measure MBP values. Factors contributing to uncertainties in MBP data were examined, and a measurement methodology designed to incorporate the uncertainties was presented. MBP measurements obtained for 5 different AN-based emulsions in high pressure vessels were also provided, and the impact of various ingredients on MBP values was discussed. Bench-scale experiments and time current pulse tests were conducted to examine thermal ignition behaviour. The emulsions exhibited MBP values that ranged from 580 to 6510 kPa. Results of the study suggested that ingredients play a significant role on MBP values. A relatively high energy flux was required to induce stable combustion fronts in the emulsions. Large air voids containing flammable atmospheres were able to provide sufficient energy to ignite the emulsions. It was concluded that a knowledge of the MBP of emulsions is needed to ensure that corresponding pumping operations are conducted at pressures below the MBP. 11 refs., 2 tabs., 8 figs.

Core–corona PSt/P(BA–AA) composite particles by two-stage emulsion polymerization

Energy Technology Data Exchange (ETDEWEB)

Xie, Delong; Ren, Xiaolin; Zhang, Xinya, E-mail: cexyzh@scut.edu.cn; Liao, Shijun [South China University of Technology, School of Chemistry and Chemical Engineering (China)

2016-03-15

Raspberry-shaped composite particles with polystyrene (PSt) as core and poly(n-butyl acrylate-co-acrylic acid) (P(BA–AA)) as corona were synthesized via emulsion polymerization. The random copolymer, P(BA–AA), was pre-prepared and used as a polymeric surfactant, its emulsifying properties adjusted by changing the mass ratio of BA and AA. The morphology of the resulting core–corona composite particles, P(St/P(BA–AA)), could be regulated and controlled by varying the concentrations of P(BA–AA) or the mass ratio of BA:AA in P(BA–AA). The experimental results indicate that 3.0–6.0 wt% of P(BA–AA) is required to obtain stable composite emulsions, and P(BA–AA) with a mass ratio of BA:AA = 1:2 is able to generate distinct core–corona structures. A mechanism of composite particle formation is proposed based on the high affinity between the PSt core and the hydrophobic segments of P(BA–A). The regular morphology of the colloidal film is expected to facilitate potential application of core–corona particles in the field of light scattering. Furthermore, the diversity of core–corona particles can be expanded by replacing P(BA–AA) corona particles with other amphiphilic particles.

Dermal oncogenicity bioassays of monofunctional and multifunctional acrylates and acrylate-based oligomers.

Science.gov (United States)

DePass, L R; Maronpot, R R; Weil, C S

1985-01-01

Several important components of photocurable coatings were studied for dermal tumorigenic activity by repeated application to the skin of mice. The substances tested were 2-ethylhexyl acrylate (EHA) and methylcarbamoyloxyethyl acrylate (MCEA) (monomers); neopentyl glycol diacrylate (NPGDA), esterdiol-204-diacrylate (EDDA), and pentaerythritol tri(tetra)acrylate (PETA) (cross-linkers); and three acrylated urethane oligomers. For each bioassay, 40 C3H/HeJ male mice were dosed 3 times weekly on the dorsal skin for their lifetime with the highest dose of the test agent that caused no local irritation or reduction in body weight gain. Two negative control groups received acetone (diluent) only. A positive control group received 0.2% methylcholanthrene (MC). NPGDA and EHA had significant tumorigenic activity with tumor yields of eight and six tumor-bearing mice (three and two malignancies), respectively. The MC group had 34 mice with carcinomas and 1 additional mouse with a papilloma. MCEA had no dermal tumorigenic activity but resulted in early mortality. No skin tumors in the treatment area were observed in the other groups. Additional studies will be necessary to elucidate possible relationships between structure and tumorigenic activity for the acrylates.

Analysis and Testing of Bisphenol A-Free Bio-Based Tannin Epoxy-Acrylic Adhesives

OpenAIRE

Jahanshahi , Shayesteh; Pizzi , Antonio; Abdulkhani , Ali; Shakeri , Alireza

2016-01-01

International audience; A tannin-based epoxy acrylate resin was prepared from glycidyl ether tannin (GET) and acrylic acid. The influence of the reaction condition for producing tannin epoxy acrylate was studied by FT-MIR, C-13-NMR, MALDI-TOF spectroscopy and shear strength. The best reaction conditions for producing tannin epoxy acrylate resin without bisphenol A was by reaction between GET and acrylic acid in the presence of a catalyst and hydroquinone at 95 degrees C for 12 h. FT-MIR, C-13...

Development of palm oil-based UV-curable epoxy acrylate and urethane acrylate resins for wood coating application

International Nuclear Information System (INIS)

Rida Tajau; Nurulhuda Mohd Yunus; Mohd Hilmi Mahmood; Mek Zah Salleh; Nik Ghazali Nik Salleh

2013-01-01

Full-text: The trend of using renewable sources such as palm oil as raw material in radiation curing is growing due to the demand from the market to produce a more environmental friendly product. In this study, the radiation curable process was done using epoxy acrylate and urethane acrylate resins which are known as epoxidized palm olein acrylate (EPOLA) and palm oil based urethane acrylate (POBUA), respectively. The purpose of the study was to investigate curing properties and the application of this UV-curable palm oil resins for wood coating. Furthermore, the properties of palm oil based coatings are compared with the petrochemical-based compound such as ebecryl (EB) for example EB264 and EB830. From the experiment done, the resins from petrochemical-based compounds resulted higher degree of crosslinking (up to 80 %) than the palm oil based compounds (up to 70 %), where the different is around 10-15 %. The hardness property from this two type coatings can reached until 50 % at the lower percentage of the oligomer. However, the coatings from petrochemical-based have a high scratch resistance as it can withstand at least up to 3.0 Newton's (N) compared to the palm oil-based compounds which are difficult to withstand the load up to 1.0 N. Finally, the test on the rubber wood substrate showed that the coatings containing benzophenone photo initiator give higher adhesion property and their also showed a higher glossiness property on the glass substrate compared to the coatings containing irgacure-819 photo initiator. This study showed that the palm oil coatings can be a suitable for the replacement of petrochemicals compound for wood coating. The palm oil coatings can be more competitive in the market if the problems of using high percentage palm oil oligomer can be overcome as the palm oil price is cheap enough. (author)

Development of palm oil-based UV-curable epoxy acrylate and urethane acrylate resins for wood coating application

International Nuclear Information System (INIS)

Tajau, Rida; Mahmood, Mohd Hilmi; Salleh, Mek Zah; Salleh, Nik Ghazali Nik; Ibrahim, Mohammad Izzat; Yunus, Nurulhuda Mohd

2014-01-01

The trend of using renewable sources such as palm oil as raw material in radiation curing is growing due to the demand from the market to produce a more environmental friendly product. In this study, the radiation curable process was done using epoxy acrylate and urethane acrylate resins which are known as epoxidised palm olein acrylate (EPOLA) and palm oil based urethane acrylate (POBUA), respectively. The purpose of the study was to investigate curing properties and the application of this UV-curable palm oil resins for wood coating. Furthermore, the properties of palm oil based coatings are compared with the petrochemical-based compound such as ebecryl (EB) i.e. EB264 and EB830. From the experiment done, the resins from petrochemical-based compounds resulted higher degree of crosslinking (up to 80%) than the palm oil based compounds (up to 70%), where the different is around 10-15%. The hardness property from this two type coatings can reached until 50% at the lower percentage of the oligomer. However, the coatings from petrochemical-based have a high scratch resistance as it can withstand at least up to 3.0 Newtons (N) compared to the palm oil-based compounds which are difficult to withstand the load up to 1.0 N. Finally, the test on the rubber wood substrate showed that the coatings containing benzophenone photoinitiator give higher adhesion property and their also showed a higher glosiness property on the glass substrate compared to the coatings containing irgacure-819 photoinitiator. This study showed that the palm oil coatings can be a suitable for the replacement of petrochemicals compound for wood coating. The palm oil coatings can be more competitive in the market if the problems of using high percentage palm oil oligomer can be overcome as the palm oil price is cheap enough

Development of palm oil-based UV-curable epoxy acrylate and urethane acrylate resins for wood coating application

Energy Technology Data Exchange (ETDEWEB)

Tajau, Rida; Mahmood, Mohd Hilmi; Salleh, Mek Zah; Salleh, Nik Ghazali Nik [Radiation Processing Technology Division, Malaysian Nuclear Agency (Nuclear Malaysia), Bangi, 43000 Kajang, Selangor (Malaysia); Ibrahim, Mohammad Izzat [Faculty of Science, University of Malaya (UM), 50603 Kuala Lumpur (Malaysia); Yunus, Nurulhuda Mohd [Faculty of Science and Technology, National University Malaysia (UKM), 43600 Bangi, Selangor (Malaysia)

2014-02-12

The trend of using renewable sources such as palm oil as raw material in radiation curing is growing due to the demand from the market to produce a more environmental friendly product. In this study, the radiation curable process was done using epoxy acrylate and urethane acrylate resins which are known as epoxidised palm olein acrylate (EPOLA) and palm oil based urethane acrylate (POBUA), respectively. The purpose of the study was to investigate curing properties and the application of this UV-curable palm oil resins for wood coating. Furthermore, the properties of palm oil based coatings are compared with the petrochemical-based compound such as ebecryl (EB) i.e. EB264 and EB830. From the experiment done, the resins from petrochemical-based compounds resulted higher degree of crosslinking (up to 80%) than the palm oil based compounds (up to 70%), where the different is around 10-15%. The hardness property from this two type coatings can reached until 50% at the lower percentage of the oligomer. However, the coatings from petrochemical-based have a high scratch resistance as it can withstand at least up to 3.0 Newtons (N) compared to the palm oil-based compounds which are difficult to withstand the load up to 1.0 N. Finally, the test on the rubber wood substrate showed that the coatings containing benzophenone photoinitiator give higher adhesion property and their also showed a higher glosiness property on the glass substrate compared to the coatings containing irgacure-819 photoinitiator. This study showed that the palm oil coatings can be a suitable for the replacement of petrochemicals compound for wood coating. The palm oil coatings can be more competitive in the market if the problems of using high percentage palm oil oligomer can be overcome as the palm oil price is cheap enough.

An update on safety and immunogenicity of vaccines containing emulsion-based adjuvants.

Science.gov (United States)

Fox, Christopher B; Haensler, Jean

2013-07-01

With the exception of alum, emulsion-based vaccine adjuvants have been administered to far more people than any other adjuvant, especially since the 2009 H1N1 influenza pandemic. The number of clinical safety and immunogenicity evaluations of vaccines containing emulsion adjuvants has correspondingly mushroomed. In this review, the authors introduce emulsion adjuvant composition and history before detailing the most recent findings from clinical and postmarketing data regarding the effects of emulsion adjuvants on vaccine immunogenicity and safety, with emphasis on the most widely distributed emulsion adjuvants, MF59® and AS03. The authors also present a summary of other emulsion adjuvants in clinical development and indicate promising avenues for future emulsion-based adjuvant development. Overall, emulsion adjuvants have demonstrated potent adjuvant activity across a number of disease indications along with acceptable safety profiles.

Effects of a fish oil-based emulsion on rat hepatoma cell invasion in culture.

Science.gov (United States)

Hagi, Akifumi; Nakayama, Mitsuo; Miura, Yutaka; Yagasaki, Kazumi

2007-01-01

Total parenteral nutrition containing a lipid emulsion is often employed after surgical tumor resection. This study investigated the effects of a fish oil-based infusion on rat hepatoma cell invasion. Rat ascites hepatoma cell line AH109A was precultured with a fish oil-based or safflower oil-based emulsion for 48 h. Changes in membranous fatty acid composition were evaluated by gas chromatography. The invasiveness of hepatoma cells was assessed by coculturing with mesentery-derived mesothelial cells. To examine ex vivo effects of the fish oil-based infusion on hepatoma invasion, sera were prepared from rats infused with fish oil- or safflower oil-based emulsion and the effects of these sera were assessed. To clarify the mechanism of inhibition of invasion by the fish oil-based emulsion, the effects of prostaglandin (PG) E(2) and PGE(3) on invasion were examined. Pretreatment with the fish oil-based emulsion reduced invasiveness without affecting growth compared with the safflower oil-based emulsion. Pretreatment with the sera from rats infused with the fish oil-based emulsion also reduced invasiveness compared with the sera from rats infused with the safflower oil-based emulsion. The addition of PGE(2) eliminated the inhibitory effect of the fish oil-based emulsion, and the addition of PGE(3) reduced the invasiveness of hepatoma cells pretreated with the safflower oil-based emulsion. These results suggest that the fish oil-based emulsion may have anti-invasive effects. Changes in the membranous fatty acid composition and consequent changes in the prostaglandins produced may be involved in this inhibitory effect.

Preparation of poly(acrylonitrile-butyl acrylate) gel electrolyte for lithium-ion batteries

International Nuclear Information System (INIS)

Tian Zheng; He Xiangming; Pu Weihua; Wan Chunrong; Jiang Changyin

2006-01-01

Poly(acrylonitrile-butyl acrylate) gel polymer electrolyte was prepared for lithium ion batteries. The preparation started with synthesis of poly(acrylonitrile-butyl acrylate) by radical emulsion polymerization, followed by phase inversion to produce microporous membrane. Then, the microporous gel polymer electrolytes (MGPEs) was prepared with the microporous membrane and LiPF 6 in ethylene carbonate/diethyl carbonate. The dry microporous membrane showed a fracture strength as high as 18.98 MPa. As-prepared gel polymer electrolytes presented ionic conductivity in excess of 3.0 x 10 -3 S cm -1 at ambient temperature and a decomposition voltage over 6.6 V. The results showed that the as-prepared gel polymer electrolytes were promising materials for Li-ion batteries

Superhydrophobic cellulose-based bionanocomposite films from Pickering emulsions

Science.gov (United States)

Bayer, Ilker S.; Steele, Adam; Martorana, Philip J.; Loth, Eric; Miller, Lance

2009-04-01

Inherently superhydrophobic and flexible cellulose-based bionanocomposites were fabricated from solid stabilized (Pickering) emulsions. Emulsions were formed by dispersing cyclosiloxanes in water stabilized by layered silicate particles and were subsequently modified by blending into a zinc oxide nanofluid. The polymer matrix was a blend of cellulose nitrate and fluoroacrylic polymer (Zonyl 8740) precompatibilized in solution. Coatings were spray cast onto aluminum substrates from polymer blends dispersed in modified Pickering emulsions. No postsurface treatment was required to induce superhydrophobicity. Effect of antiseptic additives on bionanocomposite superhydrophobicity is also discussed. Replacing cellulose nitrate with commercial liquid bandage solutions produced identical superhydrophobic coatings.

Development of soy lecithin based novel self-assembled emulsion hydrogels.

Science.gov (United States)

Singh, Vinay K; Pandey, Preeti M; Agarwal, Tarun; Kumar, Dilip; Banerjee, Indranil; Anis, Arfat; Pal, Kunal

2015-03-01

The current study reports the development and characterization of soy lecithin based novel self-assembled emulsion hydrogels. Sesame oil was used as the representative oil phase. Emulsion gels were formed when the concentration of soy lecithin was >40% w/w. Metronidazole was used as the model drug for the drug release and the antimicrobial tests. Microscopic study showed the apolar dispersed phase in an aqueous continuum phase, suggesting the formation of emulsion hydrogels. FTIR study indicated the formation of intermolecular hydrogen bonding, whereas, the XRD study indicated predominantly amorphous nature of the emulsion gels. Composition dependent mechanical and drug release properties of the emulsion gels were observed. In-depth analyses of the mechanical studies were done using Ostwald-de Waele power-law, Kohlrausch and Weichert models, whereas, the drug release profiles were modeled using Korsmeyer-Peppas and Peppas-Sahlin models. The mechanical analyses indicated viscoelastic nature of the emulsion gels. The release of the drug from the emulsion gels was diffusion mediated. The drug loaded emulsion gels showed good antimicrobial activity. The biocompatibility test using HaCaT cells (human keratinocytes) suggested biocompatibility of the emulsion gels. Copyright © 2015 Elsevier Ltd. All rights reserved.

Determining color difference thresholds in denture base acrylic resin.

Science.gov (United States)

Ren, Jiabao; Lin, Hong; Huang, Qingmei; Zheng, Gang

2015-11-01

In restorative prostheses, color is important, but the choice of color difference formula used to quantify color change in acrylic resins is not straightforward. The purpose of this in vitro study was to choose a color difference formula that best represented differences between the calculated color and the observed imperceptible to unacceptable color and to determine the corresponding perceptibility and acceptability threshold of color stability for denture base acrylic resins. A total of 291 acrylic resin denture base plates were fabricated and subjected to radiation tests from zero to 42 hours in accordance with ISO 7491:2000. Color was measured with a portable spectrophotometer, and color differences were calculated with 3 International Commission on Illumination (CIE) formulas: CIELab, CMC(1:1), and CIEDE2000. Thirty-four observers with no deficiencies in color perception participated in psychophysical perceptibility and acceptability assessments under controlled conditions in vitro. These 2 types of assessments were regressed to each observer by each formula to generate receiver operator characteristic (ROC) curves. Areas under the curves (AUCs) were then calculated and analyzed to exclude observers with poor color discrimination. AUCs were subjected to 1-way ANOVA (α=.05) to deter the statistical significance of discriminability among the 3 formulas in terms of perceptibility and acceptability judgments. Student-Newman-Keuls tests (α=.05) were used for post hoc comparison. CMC(1:1) and CIEDE2000 formulas performed better for imperceptible to unacceptable color differences, with corresponding CMC(1:1) and CIEDE2000 values for perceptibility of 2.52 and 1.72, respectively, and acceptability thresholds of 6.21 and 4.08, respectively. Formulas CMC(1:1) and CIEDE2000 possess higher discriminability than that of CIELab in the assessment of perceptible color difference threshold of denture base acrylic resin. A statistically significant difference exists

Synthesis of Radiation Curable Palm Oil-Based Epoxy Acrylate: NMR and FTIR Spectroscopic Investigations.

Science.gov (United States)

Salih, Ashraf M; Ahmad, Mansor Bin; Ibrahim, Nor Azowa; Dahlan, Khairul Zaman Hj Mohd; Tajau, Rida; Mahmood, Mohd Hilmi; Yunus, Wan Md Zin Wan

2015-08-04

Over the past few decades, there has been an increasing demand for bio-based polymers and resins in industrial applications, due to their potential lower cost and environmental impact compared with petroleum-based counterparts. The present research concerns the synthesis of epoxidized palm oil acrylate (EPOLA) from an epoxidized palm oil product (EPOP) as environmentally friendly material. EPOP was acrylated by acrylic acid via a ring opening reaction. The kinetics of the acrylation reaction were monitored throughout the reaction course and the acid value of the reaction mixture reached 10 mg KOH/g after 16 h, indicating the consumption of the acrylic acid. The obtained epoxy acrylate was investigated intensively by means of FTIR and NMR spectroscopy, and the results revealed that the ring opening reaction was completed successfully with an acrylation yield about 82%. The UV free radical polymerization of EPOLA was carried out using two types of photoinitiators. The radiation curing behavior was determined by following the conversion of the acrylate groups. The cross-linking density and the hardness of the cured EPOLA films were measured to evaluate the effect of the photoinitiator on the solid film characteristics, besides, the thermal and mechanical properties were also evaluated.

Preparation of poly(acrylonitrile-butyl acrylate) gel electrolyte for lithium-ion batteries

Energy Technology Data Exchange (ETDEWEB)

Tian Zheng [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); He Xiangming [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China)]. E-mail: hexm@tsinghua.edu.cn; Pu Weihua [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Wan Chunrong [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Jiang Changyin [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China)

2006-10-25

Poly(acrylonitrile-butyl acrylate) gel polymer electrolyte was prepared for lithium ion batteries. The preparation started with synthesis of poly(acrylonitrile-butyl acrylate) by radical emulsion polymerization, followed by phase inversion to produce microporous membrane. Then, the microporous gel polymer electrolytes (MGPEs) was prepared with the microporous membrane and LiPF{sub 6} in ethylene carbonate/diethyl carbonate. The dry microporous membrane showed a fracture strength as high as 18.98 MPa. As-prepared gel polymer electrolytes presented ionic conductivity in excess of 3.0 x 10{sup -3} S cm{sup -1} at ambient temperature and a decomposition voltage over 6.6 V. The results showed that the as-prepared gel polymer electrolytes were promising materials for Li-ion batteries.

Compliant gel polymer electrolyte based on poly(methyl acrylate-co-acrylonitrile)/poly(vinyl alcohol) for flexible lithium-ion batteries

International Nuclear Information System (INIS)

Ma, Xianguo; Huang, Xinglan; Gao, Jiandong; Zhang, Shu; Deng, Zhenghua; Suo, Jishuan

2014-01-01

Highlights: •Compliant gel polymer electrolyte based on P(MA-co-AN)/PVA is facilely prepared for flexible lithium-ion batteries. •The compliant gel polymer electrolyte displays high ionic conductivity, self-standing and mechanical flexible. •The compliant gel polymer electrolyte exhibits excellent chemical and electrochemical performances. -- Abstract: In this report, mechanically compliant gel polymer electrolyte (GPE) for flexible lithium-ion batteries is facilely fabricated. The GPE that based on the poly(methyl acrylate-co-acrylonitrile)/poly(vinyl alcohol) (P(MA-co-AN)/PVA) was prepared via emulsion polymerization. Herein, the P(MA-co-AN) copolymer is anticipated to exert beneficial for the bendability of the GPE, as well as swollen with the liquid electrolyte to provide a facile pathway for ion movement. The PVA serves as a stabilizer during the emulsion polymerization and a mechanical framework for the compliant polymer membrane. Performance benefits of the mechanically compliant membrane are elucidated in terms of mechanical behavior, thermostability and ionic conductivity. The GPE is still self-standing and mechanical flexible after swollen with liquid electrolyte. The GPE displays a conductivity of 0.98 mS cm −1 with the uptake electrolyte up to 150% of its own weight at 30 °C, excellent electrochemical stability window (5.2 V vs. Li/Li + ) and favorable interfacial characteristics. When used in flexible lithium-ion batteries, such a GPE demonstrates satisfactory compatibility with LiCoO 2 and graphite electrodes

Encapsulation of Polymethoxyflavones in Citrus Oil Emulsion-Based Delivery Systems.

Science.gov (United States)

Yang, Ying; Zhao, Chengying; Chen, Jingjing; Tian, Guifang; McClements, David Julian; Xiao, Hang; Zheng, Jinkai

2017-03-01

The purpose of this work was to elucidate the effects of citrus oil type on polymethoxyflavone (PMF) solubility and on the physicochemical properties of PMF-loaded emulsion-based delivery systems. Citrus oils were extracted from mandarin, orange, sweet orange, and bergamot. The major constituents were determined by GC/MS: sweet orange oil (97.4% d-limonene); mandarin oil (72.4% d-limonene); orange oil (67.2% d-limonene); and bergamot oil (34.6% linalyl acetate and 25.3% d-limonene). PMF-loaded emulsions were fabricated using 10% oil phase (containing 0.1% w/v nobiletin or tangeretin) and 90% aqueous phase (containing 1% w/v Tween 80) using high-pressure homogenization. Delivery systems prepared using mandarin oil had the largest mean droplet diameters (386 or 400 nm), followed by orange oil (338 or 390 nm), bergamot oil (129 or 133 nm), and sweet orange oil (122 or 126 nm) for nobiletin- or tangeretin-loaded emulsions, respectively. The optical clarity of the emulsions increased with decreasing droplet size due to reduced light scattering. The viscosities of the emulsions (with or without PMFs) were similar (1.3 to 1.4 mPa·s), despite appreciable differences in oil phase viscosity. The loading capacity and encapsulation efficiency of the emulsions depended on carrier oil type, with bergamot oil giving the highest loading capacity. In summary, differences in the composition and physical characteristics of citrus oils led to PMF-loaded emulsions with different encapsulation and physicochemical characteristics. These results will facilitate the rational design of emulsion-based delivery systems for encapsulation of PMFs and other nutraceuticals in functional foods and beverages.

Analysis and Testing of Bisphenol A—Free Bio-Based Tannin Epoxy-Acrylic Adhesives

Directory of Open Access Journals (Sweden)

Shayesteh Jahanshahi

2016-04-01

Full Text Available A tannin-based epoxy acrylate resin was prepared from glycidyl ether tannin (GET and acrylic acid. The influence of the reaction condition for producing tannin epoxy acrylate was studied by FT-MIR, 13C-NMR, MALDI-TOF spectroscopy and shear strength. The best reaction conditions for producing tannin epoxy acrylate resin without bisphenol A was by reaction between GET and acrylic acid in the presence of a catalyst and hydroquinone at 95 °C for 12 h. FT-MIR, 13C-NMR and MALDI-TOF analysis have confirmed that the resin has been prepared under these conditions. The joints bonded with this resin were tested for block shear strength. The results obtained indicated that the best strength performance was obtained by the bioepoxy-acrylate adhesive resin prepared at 95 °C for a 12-h reaction.

Mitigation of biofilm formation on corrugated cardboard fresh produce packaging surfaces using a novel thiazolidinedione derivative integrated in acrylic emulsion polymers

Directory of Open Access Journals (Sweden)

Michael eBrandwein

2016-02-01

Full Text Available Various surfaces associated with the storage and packing of food are known to harbor distinct bacterial pathogens. Conspicuously absent among the plethora of studies implicating food packaging materials and machinery is the study of corrugated cardboard packaging, the worldwide medium for transporting fresh produce. In this study, we observed the microbial communities of three different store-bought fruits and vegetables, along with their analogue cardboard packaging using high throughput sequencing technology. We further developed an anti-biofilm polymer meant to coat corrugated cardboard surfaces and mediate bacterial biofilm growth on said surfaces. Integration of a novel thiazolidinedione derivative into the acrylic emulsion polymers was assessed using Energy Dispersive X-ray Spectrometry analysis and surface topography was visualized and quantified on corrugated cardboard surfaces. Biofilm growth was measured using q-PCR targeting the gene encoding 16s rRNA. Additionally, architectural structure of the biofilm was observed using SEM. The uniform integration of the thiazolidinedione derivative TZD-6 was confirmed, and it was determined via q-PCR to reduce biofilm growth by ~80% on tested surfaces. A novel and effective method for reducing microbial load and preventing contamination on food packaging is thereby proposed.

Mitigation of Biofilm Formation on Corrugated Cardboard Fresh Produce Packaging Surfaces Using a Novel Thiazolidinedione Derivative Integrated in Acrylic Emulsion Polymers.

Science.gov (United States)

Brandwein, Michael; Al-Quntar, Abed; Goldberg, Hila; Mosheyev, Gregory; Goffer, Moshe; Marin-Iniesta, Fulgencio; López-Gómez, Antonio; Steinberg, Doron

2016-01-01

Various surfaces associated with the storage and packing of food are known to harbor distinct bacterial pathogens. Conspicuously absent among the plethora of studies implicating food packaging materials and machinery is the study of corrugated cardboard packaging, the worldwide medium for transporting fresh produce. In this study, we observed the microbial communities of three different store-bought fruits and vegetables, along with their analog cardboard packaging using high throughput sequencing technology. We further developed an anti-biofilm polymer meant to coat corrugated cardboard surfaces and mediate bacterial biofilm growth on said surfaces. Integration of a novel thiazolidinedione derivative into the acrylic emulsion polymers was assessed using Energy Dispersive X-ray Spectrometry (EDS) analysis and surface topography was visualized and quantified on corrugated cardboard surfaces. Biofilm growth was measured using q-PCR targeting the gene encoding 16s rRNA. Additionally, architectural structure of the biofilm was observed using SEM. The uniform integration of the thiazolidinedione derivative TZD-6 was confirmed, and it was determined via q-PCR to reduce biofilm growth by ~80% on tested surfaces. A novel and effective method for reducing microbial load and preventing contamination on food packaging is thereby proposed.

Influences of Electrolytes on the Soap-free Emulsion Copolymerization of St-MMA-AA

Institute of Scientific and Technical Information of China (English)

Rong Long LI; Cheng You KAN; Yi DU; Ze Ping LI

2006-01-01

Monodisperse functional polymer microspheres with different particle size and with clean surface were prepared by batch soap-free emulsion polymerization of styrene, methyl methacrylate and acrylic acid in the presence of salts, and the influences of type and amount of electrolytes on polymerization process and particle morphology were investigated. Results showed that there was a critical concentration for different electrolyte to make polymerization process and the resultant emulsion stable, and the particle size increased with the increase of electrolyte concentration. The effect of metal ions was Ca2+＞＞K+＞Na+＞Li+, and the effect of haloids was Br-＞Cl-＞F-.

Instant polysaccharide-based emulsions: impact of microstructure on lipolysis.

Science.gov (United States)

Torcello-Gómez, Amelia; Foster, Timothy J

2017-06-21

The development of emulsion-based products through optimisation of ingredients, reduction in energy-input during manufacture, while fulfilling healthy attributes, are major objectives within the food industry. Instant emulsions can meet these features, but comprehensive studies are necessary to investigate the effect of the initial formulation on the final microstructure and, in turn, on the in vitro lipolysis, comprising the double aim of this work. The instant emulsion is formed within 1.5-3 min after pouring the aqueous phase into the oil phase which contains a mixture of emulsifier (Tween 20), swelling particles (Sephadex) and thickeners (hydroxypropylmethylcellulose, HPMC, and guar gum, GG) under mild shearing (180 rpm). The creation of oil-in-water emulsions is monitored in situ by viscosity analysis, the final microstructure visualised by microscopy and the release of free fatty acids under simulated intestinal conditions quantified by titration. Increasing the concentration and molecular weight (M w ) of GG leads to smaller emulsion droplets due to increased bulk viscosity upon shearing. This droplet size reduction is magnified when increasing the M w of HPMC or swelling capacity of viscosifying particles. In addition, in the absence of the emulsifier Tween 20, the sole use of high-Mw HPMC is effective in emulsification due to combined increased bulk viscosity and interfacial activity. Hence, optimisation of the ingredient choice and usage level is possible when designing microstructures. Finally, emulsions with larger droplet size (>20 μm) display a slower rate and lower extent of lipolysis, while finer emulsions (droplet size ≤20 μm) exhibit maximum rate and extent profiles. This correlates with the extent of emulsion destabilisation observed under intestinal conditions.

High-impact strength acrylic denture base material processed by autoclave.

Science.gov (United States)

Abdulwahhab, Salwan Sami

2013-10-01

To investigate the effect of two different cycles of autoclave processing on the transverse strength, impact strength, surface hardness and the porosity of high-impact strength acrylic denture base material. High Impact Acryl was the heat-cured acrylic denture base material included in the study. A total of 120 specimens were prepared, the specimens were grouped into: control groups in which high-impact strength acrylic resins processed by conventional water-bath processing technique (74°C for 1.5 h then boil for 30 min) and experimental groups in which high-impact strength acrylic resins processed by autoclave at 121°C, 210 kPa .The experimental groups were divided into (fast) groups for 15 min, and (slow) groups for 30 min. To study the effect of the autoclave processing (Tuttnauer 2540EA), four tests were conducted transverse strength (Instron universal testing machine), impact strength (Charpy tester), surface hardness (shore D), and porosity test. The results were analyzed to ANOVA and LSD test. In ANOVA test, there were highly significant differences between the results of the processing techniques in transverse, impact, hardness, and porosity test. The LSD test showed a significant difference between control and fast groups in transverse and hardness tests and a non-significant difference in impact test and a highly significant difference in porosity test; while, there were a highly significant differences between control and slow groups in all examined tests; finally, there were a non-significant difference between fast and slow groups in transverse and porosity tests and a highly significant difference in impact and hardness tests. In the autoclave processing technique, the slow (long) curing cycle improved the tested physical and mechanical properties as compared with the fast (short) curing cycle. The autoclave processing technique improved the tested physical and mechanical properties of High Impact Acryl. Copyright © 2013 Japan Prosthodontic Society

Tannin-based monoliths from emulsion-templating

International Nuclear Information System (INIS)

Szczurek, A.; Martinez de Yuso, A.; Fierro, V.; Pizzi, A.; Celzard, A.

2015-01-01

Highlights: • Efficient preparation procedures are presented for new and “green” tannin-based organic polyHIPEs. • Highest homogeneity and strength are obtained at an oil fraction near the close-packing value. • Structural and mechanical properties abruptly change above such critical value. - Abstract: Highly porous monoliths prepared by emulsion-templating, frequently called polymerised High Internal Phase Emulsions (polyHIPEs) in the literature, were prepared from “green” precursors such as Mimosa bark extract, sunflower oil and ethoxylated castor oil. Various oil fractions, ranging from 43 to 80 vol.%, were used and shown to have a dramatic impact on the resultant porous structure. A critical oil fraction around 70 vol.% was found to exist, close to the theoretical values of 64% and 74% for random and compact sphere packing, respectively, at which the properties of both emulsions and derived porous monoliths changed. Such change of behaviour was observed by many different techniques such as viscosity, electron microscopy, mercury intrusion, and mechanical studies. We show and explain why this critical oil fraction is the one leading to the strongest and most homogeneous porous monoliths

[Acrylic resin removable partial dentures].

Science.gov (United States)

de Baat, C; Witter, D J; Creugers, N H J

2011-01-01

An acrylic resin removable partial denture is distinguished from other types of removable partial dentures by an all-acrylic resin base which is, in principle, solely supported by the edentulous regions of the tooth arch and in the maxilla also by the hard palate. When compared to the other types of removable partial dentures, the acrylic resin removable partial denture has 3 favourable aspects: the economic aspect, its aesthetic quality and the ease with which it can be extended and adjusted. Disadvantages are an increased risk of caries developing, gingivitis, periodontal disease, denture stomatitis, alveolar bone reduction, tooth migration, triggering of the gag reflex and damage to the acrylic resin base. Present-day indications are ofa temporary or palliative nature or are motivated by economic factors. Special varieties of the acrylic resin removable partial denture are the spoon denture, the flexible denture fabricated of non-rigid acrylic resin, and the two-piece sectional denture. Furthermore, acrylic resin removable partial dentures can be supplied with clasps or reinforced by fibers or metal wires.

Generation of colloidal granules and capsules from double emulsion drops

Science.gov (United States)

Hess, Kathryn S.

Assemblies of colloidal particles are extensively used in ceramic processing, pharmaceuticals, inks and coatings. In this project, the aim was to develop a new technique to fabricate monodispersed colloidal assemblies. The use of microfluidic devices and emulsion processing allows for the fabrication of complex materials that can be used in a variety of applications. A microfluidic device is used to create monodispersed water/oil/water (w/o/w) double emulsions with interior droplets of colloidal silica suspension ranging in size from tens to hundreds of microns. By tailoring the osmotic pressure using glycerol as a solute in the continuous and inner phases of the emulsion, we can control the final volume size of the monodispersed silica colloidal crystals that form in the inner droplets of the double emulsion. Modifying the ionic strength in the colloidal dispersion can be used to affect the particle-particle interactions and crystal formation of the final colloidal particle. This w/o/w technique has been used with other systems of metal oxide colloids and cellulose nanocrystals. Encapsulation of the colloidal suspension in a polymer shell for the generation of ceramic-polymer core-shell particles has also been developed. These core-shell particles have spawned new research in the field of locally resonant acoustic metamaterials. Systems and chemistries for creating cellulose hydrogels within the double emulsions have also been researched. Water in oil single emulsions and double emulsions have been used to create cellulose hydrogel spheres in the sub-100 micron diameter range. Oil/water/oil double emulsions allow us to create stable cellulose capsules. The addition of a second hydrogel polymer, such as acrylate or alginate, further strengthens the cellulose gel network and can also be processed into capsules and particles using the microfluidic device. This work could have promising applications in acoustic metamaterials, personal care products, pharmaceuticals

Synthesis and Characterization of Core-Shell Acrylate Based Latex and Study of Its Reactive Blends

Directory of Open Access Journals (Sweden)

Ying Nie

2008-03-01

Full Text Available Techniques in resin blending are simple and efficient method for improving the properties of polymers, and have been used widely in polymer modification field. However, polymer latex blends such as the combination of latexes, especially the latexes with water-soluble polymers, were rarely reported. Here, we report a core-shell composite latex synthesized using methyl methacrylate (MMA, butyl acrylate (BA, 2-ethylhexyl acrylate (EHA and glycidyl methacrylate (GMA as monomers and ammonium persulfate and sodium bisulfite redox system as the initiator. Two stages seeded semi-continuous emulsion polymerization were employed for constructing a core-shell structure with P(MMA-co-BA component as the core and P(EHA-co-GMA component as the shell. Results of Transmission Electron Microscopy (TEM and Dynamics Light Scattering (DLS tests confirmed that the particles obtained are indeed possessing a desired core-shell structural character. Stable reactive latex blends were prepared by adding the latex with waterborne melamine-formaldehyde resin (MF or urea-formaldehyde resin (UF. It was found that the glass transition temperature, the mechanical strength and the hygroscopic property of films cast from the latex blends present marked enhancements under higher thermal treatment temperature. It was revealed that the physical properties of chemically reactive latexes with core-shell structure could be altered via the change of crosslinking density both from the addition of crosslinkers and the thermal treatment.

Study on Tough Blends of Polylactide and Acrylic Impact Modifier

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Xiaoli Song

2014-02-01

Full Text Available Acrylic impact modifiers (ACRs with different soft/hard monomer ratios (mass ratios were prepared by semi-continuous seed emulsion copolymerization using the soft monomer butyl acrylate and the hard monomer methyl methacrylate, which were used to toughen polylactide (PLA. The effect of soft/hard ACR monomer ratio on the mechanical properties of PLA/ACR blends was investigated. The results showed that the impact strength and the elongation at break of PLA/ACR blends increased with increasing soft/hard ACR monomer ratio, while the tensile and flexural strengths of PLA had little change. The impact strength of PLA/ACR blends could be increased about 4 times more than that of pure PLA when the soft/hard monomer ratio of ACR was 90/10, which was the optimal ratio for good mechanical properties of PLA. Additionally, the possible mechanism of ACR toughening in PLA was discussed through impact fracture phase morphology analysis.

Performance and behaviour of bitumen emulsion treated road bases in South Africa.

CSIR Research Space (South Africa)

Horak, E

1992-08-01

Full Text Available Emulsion treatment of granular bases is used mostly as a rehabilitation option in South Africa. Emulsion treated bases (ETBs) have been used on an ad hoc basis in South Africa in the past. Considerable work has gone into the mix design of ETBs...

Preparation of an Adhesive in Emulsion for Maxillofacial Prosthetic

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Joaquín Palacios-Alquisira

2010-10-01

Full Text Available Maxillofacial prostheses is a dental medicine specialty aimed at restoring anatomical facial defects caused by cancer, trauma or congenital malformations through an artificial device, which is commonly attached to the skin with the help of an adhesive. The purpose of our research was to develop a pressure-sensitive adhesive (PSA based on acrylic monomers, characterizing and determining its drying kinetics, that is to say the time it takes to lose 50 to 90% of its moisture. The adhesive synthesis was realized by means of emulsion polymerization; the composition of formulations was: (AA‑MMA‑EA and (AA‑MMA‑2EHA with different molar ratios. The formulation based on (AA‑MMA‑2EHA with 50 w% of solids, presented good adhesive properties such as tack, bond strength, and short drying time. We propose this formulation as a PSA, because it offers an alternative for systemically compromised patients, by less irritation compared to organic solvent-based adhesives.

Comparative analysis of skin sensitization potency of acrylates (methyl acrylate, ethyl acrylate, butyl acrylate, and ethylhexyl acrylate) using the local lymph node assay.

Science.gov (United States)

Dearman, Rebecca J; Betts, Catherine J; Farr, Craig; McLaughlin, James; Berdasco, Nancy; Wiench, Karin; Kimber, Ian

2007-10-01

There are currently available no systematic experimental data on the skin sensitizing properties of acrylates that are of relevance in occupational settings. Limited information from previous guinea-pig tests or from the local lymph node assay (LLNA) is available; however, these data are incomplete and somewhat contradictory. For those reasons, we have examined in the LLNA 4 acrylates: butyl acrylate (BA), ethyl acrylate (EA), methyl acrylate (MA), and ethylhexyl acrylate (EHA). The LLNA data indicated that all 4 compounds have some potential to cause skin sensitization. In addition, the relative potencies of these acrylates were measured by derivation from LLNA dose-response analyses of EC3 values (the effective concentration of chemical required to induce a threefold increase in proliferation of draining lymph node cells compared with control values). On the basis of 1 scheme for the categorization of skin sensitization potency, BA, EA, and MA were each classified as weak sensitizers. Using the same scheme, EHA was considered a moderate sensitizer. However, it must be emphasized that the EC3 value for this chemical of 9.7% is on the borderline between moderate (10%) categories. Thus, the judicious view is that all 4 chemicals possess relatively weak skin sensitizing potential.

Ca (OH)2Nanoparticles Based on Acrylic Copolymers for the consolidation and protection of Ancient Egypt Calcareous Stone Monuments

Science.gov (United States)

Al-Dosari, Mohammad A.; Darwish, Sawsan S.; Adam, Mahmoud A.; Elmarzugi, Nagib A.; Al-Mouallimi, Nadia; Ahmed, Sayed M.

2017-04-01

The deterioration of calcareous stones materials used in artistic/architectural field is one of the most serious problems facing conservation today. The aim of this study was to evaluate the effectiveness of nanosized particles of calcium hydroxide (slaked lime) as a consolidation and protection material dispersed in acrylic copolymer, poly ethylmethacrylate/methylacrylate (70:30) (Poly (EMA/MA), for calcareous stone monuments and painted surfaces affected by different kinds of decay. The synthesis process of Ca (OH)2 nanoparticles/polymer nanocomposites have been prepared by in situ emulsion polymerization system. The prepared nanocomposite containing 5% of Ca (OH)2 nanoparticles showed obvious transparency features and represent nanocomposites coating technology with hydrophobic, consolidating and well protection properties.

Ca (OH)2Nanoparticles Based on Acrylic Copolymers for the consolidation and protection of Ancient Egypt Calcareous Stone Monuments

International Nuclear Information System (INIS)

Al-Dosari, Mohammad A.; Ahmed, Sayed M.; Darwish, Sawsan S.; Adam, Mahmoud A.; Elmarzugi, Nagib A.; Al-Mouallimi, Nadia

2017-01-01

The deterioration of calcareous stones materials used in artistic/architectural field is one of the most serious problems facing conservation today. The aim of this study was to evaluate the effectiveness of nanosized particles of calcium hydroxide (slaked lime) as a consolidation and protection material dispersed in acrylic copolymer, poly ethylmethacrylate/methylacrylate (70:30) (Poly (EMA/MA), for calcareous stone monuments and painted surfaces affected by different kinds of decay. The synthesis process of Ca (OH) 2 nanoparticles/polymer nanocomposites have been prepared by in situ emulsion polymerization system. The prepared nanocomposite containing 5% of Ca (OH) 2 nanoparticles showed obvious transparency features and represent nanocomposites coating technology with hydrophobic, consolidating and well protection properties. (paper)

Elastic modulus and flexural strength comparisons of high-impact and traditional denture base acrylic resins

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Nour M. Ajaj-ALKordy

2014-01-01

Conclusion: Within the limitations of this study, it can be concluded that the high-impact acrylic resin is a suitable denture base material for patients with clinical fracture of the acrylic denture.

Fabrication of magnetic hydroxypropyl cellulose-g-poly(acrylic acid) porous spheres via Pickering high internal phase emulsion for removal of Cu(2+) and Cd(2.).

Science.gov (United States)

Zhu, Yongfeng; Zheng, Yian; Zong, Li; Wang, Feng; Wang, Aiqin

2016-09-20

A series of magnetic hydroxypropyl cellulose-g-poly(acrylic acid) porous spheres were prepared via O/W Pickering high internal phase emulsions (HIPEs) integrated precipitation polymerization. The structure and composition of modified Fe3O4 and porous structures were characterized by TEM, XRD, TGA and SEM. The results indicated that the silanized Fe3O4 can influence greatly the pore structure of magnetic porous sphere in addition to non-negligible impacts of the proportion of mixed solvent and co-surfactant. The adsorption experiment demonstrated that the adsorption equilibrium can be reached within 40min and the maximal adsorption capacity was 300.00mg/g for Cd(2+) and 242.72mg/g for Cu(2+), suggesting its fast adsorption kinetics and high adsorption capacity. After five adsorption-desorption cycles, no significant changes in the adsorption capacity were observed, suggesting its excellent reusability. The magnetic porous sphere can be easily separated from the solution and then find its potential as a recyclable material for highly efficient removal of heavy metals. Copyright © 2016 Elsevier Ltd. All rights reserved.

Stability of poly(N-isopropylacrylamide-co-acrylic acid polymer microgels under various conditions of temperature, pH and salt concentration

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Zahoor H. Farooqi

2017-03-01

Full Text Available This research article describes the colloidal stability of poly(N-isopropylacrylamide-co-acrylic acid [P(NIPAM-co-AAc] polymer microgels with different acrylic acid contents in aqueous medium under various conditions of temperature, pH and sodium chloride concentrations. Three samples of multi-responsive P(NIPAM-co-AAc polymer microgels were synthesized using different amounts of acrylic acid by free radical emulsion polymerization. Dynamic laser light scattering was used to investigate the responsive behavior and stability of the prepared microgels under various conditions of pH, temperature and ionic strength. The microgels were found to be stable at all pH values above the pKa value of acrylic acid moiety in the temperature range from 15 to 60 °C in the presence and absence of sodium chloride. Increase in temperature, salt concentration and decrease in pH causes aggregation and decreases the stability of microgels due to the decrease in hydrophilicity.

A comparison of properties between carboxylated acrylic rubbers prepared by γ-ray irradiation and chemical method

International Nuclear Information System (INIS)

Wang Weiwei; Chang Zhenqi; Wang Mozhen; Zhang Zhicheng; Lv Pin

2006-01-01

Acrylic rubbers (ACM) carboxylated by acrylic acid or itaconic acid were prepared by 60 Co γ-ray or chemical-initiator (K 2 S 2 O 8 ) induced emulsion copolymerization. The polymers were characterized by Fourier transform infrared spectroscopy (FT-IR). Acid value, molecular weight and polydispersity index (PDI) of the polymers were determined by non-aqueous titration method and gel permeation chromatography (GPC), respectively. Vulcanization and mechanical properties of the filled ACM were studied by rheometric measurement, gel fraction analysis, mechanical property tests and dynamic mechanical thermal analysis (DMTA). The results show that the ACMs prepared by γ-ray irradiation have lower acid value, higher molecular weight and narrower PDI than chemically prepared ACMs of the same compositions. The itaconic acid carboxylated ACM has better cure characteristics and mechanical properties than the acrylic acid carboxylated ACM. The itaconic acid carboxylated ACM prepared by γ-ray irradiation has higher gel fraction and better cure characteristics as well as mechanical properties than that prepared by chemical method. (authors)

Hot-wire ignition of AN-based emulsions

Energy Technology Data Exchange (ETDEWEB)

Turcotte, Richard; Goldthorp, Sandra; Badeen, Christopher M. [Canadian Explosives Research Laboratory, Natural Resources Canada, Ottawa, Ontario, K1A 0G1 (Canada); Chan, Sek Kwan [Orica Canada Inc., Brownsburg-Chatham, Quebec (Canada)

2008-12-15

Emulsions based on ammonium nitrate (AN) and water locally ignited by a heat source do not undergo sustained combustion when the pressure is lower than some threshold value usually called the Minimum Burning Pressure (MBP). This concept is now being used by some manufacturers as a basis of safety. However, before a technique to reliably measure MBP values can be designed, one must have a better understanding of the ignition mechanism. Clearly, this is required to avoid under ignitions which could lead to the erroneous interpretation of failures to ignite as failures to propagate. In the present work, facilities to prepare and characterize emulsions were implemented at the Canadian Explosives Research Laboratory. A calibrated hot-wire ignition system operated in a high-pressure vessel was also built. The system was used to study the ignition characteristics of five emulsion formulations as a function of pressure and ignition source current. It was found that these mixtures exhibit complicated pre-ignition stages and that the appearance of endotherms when the pressure is lowered below some threshold value correlates with the MBP. Thermal conductivity measurements using this hot-wire system are also reported. (Abstract Copyright [2008], Wiley Periodicals, Inc.)

Highly tailorable thiol-ene based emulsion-templated monoliths

DEFF Research Database (Denmark)

Lafleur, J. P.; Kutter, J. P.

2014-01-01

The attractive surface properties of thiol-ene polymers combined with their ease of processing make them ideal substrates in many bioanalytical applications. We report the synthesis of highly tailorable emulsion-templated porous polymers and beads in microfluidic devices based on off-stoichiometr......The attractive surface properties of thiol-ene polymers combined with their ease of processing make them ideal substrates in many bioanalytical applications. We report the synthesis of highly tailorable emulsion-templated porous polymers and beads in microfluidic devices based on off......-stoichiometry thiolene chemistry. The method allows monolith synthesis and anchoring inside thiol-ene microchannels in a single step. Variations in the monomer stoichiometric ratios and/or amount of porogen used allow for the creation of extremely varied polymer morphologies, from foam-like materials to dense networks...

Systematic investigation of the synthesis of core-shell poly(styrene-co-acrylic acid) colloids with varying shell thickness and core diameter

DEFF Research Database (Denmark)

Hinge, Mogens; Keiding, Kristian

2006-01-01

the morphology of the material for an specific application is going on. It is known from SFEP of styrene that the final colloidal size can be controlled by adjusting the ionic strength of the synthesis feed [1] and it is suggested that adding acrylic acid to the synthesis will result in a change...... in polymerization locus from the core to the surface [2]. There is at present not performed a systematically investigation in controlling the core size and shell thickness of poly(styrene-co-acrylic acid) core-shell colloids  (poly(ST-co-AA)).   Poly(ST-co-AA) colloids were synthesized by free-radical surfactant......-free emulsion co-polymerization (SFECP) at 70°C, using styrene as monomer and acrylic acid as co-monomer. Different batches of poly(ST-co-AA) colloids were synthesized with varying ionic strength and acrylic acid concentrations in the synthesis feed. The produced poly(ST-co-AA) colloids were analysed...

Construction and optimization of an efficient breathing-based isothermal emulsion amplification method

Energy Technology Data Exchange (ETDEWEB)

Shen, Yanting, E-mail: shenyanting798@126.com [Research Center for Learning Science, Southeast University, Sipailou Road no. 2, Nanjing, Jiangsu Province 210096 (China); State Key Laboratory of Bioelectronics, Southeast University, Sipailou Road no. 2, Nanjing, Jiangsu Province 210096 (China); Tian, Fei, E-mail: 642807827@qq.com [Research Center for Learning Science, Southeast University, Sipailou Road no. 2, Nanjing, Jiangsu Province 210096 (China); Tu, Jing, E-mail: jtu@seu.edu.cn [State Key Laboratory of Bioelectronics, Southeast University, Sipailou Road no. 2, Nanjing, Jiangsu Province 210096 (China); Li, Rui, E-mail: lirui901113@163.com [Research Center for Learning Science, Southeast University, Sipailou Road no. 2, Nanjing, Jiangsu Province 210096 (China); Chen, Zhenzhu, E-mail: zzchen_seu@163.com [Research Center for Learning Science, Southeast University, Sipailou Road no. 2, Nanjing, Jiangsu Province 210096 (China); Bai, Yunfei, E-mail: whitecf@seu.edu.cn [State Key Laboratory of Bioelectronics, Southeast University, Sipailou Road no. 2, Nanjing, Jiangsu Province 210096 (China); Ge, Qinyu, E-mail: geqinyu@seu.edu.cn [State Key Laboratory of Bioelectronics, Southeast University, Sipailou Road no. 2, Nanjing, Jiangsu Province 210096 (China); Lu, Zuhong, E-mail: zhlu@seu.edu.cn [State Key Laboratory of Bioelectronics, Southeast University, Sipailou Road no. 2, Nanjing, Jiangsu Province 210096 (China)

2017-06-22

The reaction temperature is one of the main factors that affect the stability of emulsion PCR (emPCR). Focusing on this point, we applied the “DNA breathing” mechanism in BEAMing (Bead, Emulsion, Amplification, and Magnetic) and proposed a more stable emulsion amplification method. Compared to the conventional emPCR, this method provided excellent results. Firstly, more stable emulsion system resulted in higher percentage of single-molecular amplifications (73.17%). Secondly, an ordinary temperature-controlling device was enough. Our outcome showed that the reaction temperature of this method was not strict so that the ordinary temperature-controlling device was enough for it (the heat block sets vs. the PCR instrument: 13.140 ± 0.110 vs. 13.008 ± 0.039, P = 0.120). Thirdly, the single-biotinylated emP{sub 1} coated streptavidin beads were stable enough to be used for this method (the control temperature vs. the reaction temperature: 2967.91 ± 409.045 vs. 3026.22 ± 442.129, P = 0.334), which could replace the double-biotinylated emP{sub 1} coated beads and was benefit for saving cost. In conclusion, the method presented here with stable emulsion system, simplified temperature-controlling device, and decreased investment would be a highly streamlined and inexpensive option for future single-molecular amplification based researches. - Highlights: • A breathing-based isothermal emulsion amplification (BIEA) method was developed. • BIEA showed excellent properties compared with conventional amplification method. • Terminal breathing of DNA duplex was firstly used in emulsion amplification.

Different magnesium release profiles from W/O/W emulsions based on crystallized oils.

Science.gov (United States)

Herzi, Sameh; Essafi, Wafa

2018-01-01

Water-in-oil-in-water (W/O/W) double emulsions based on crystallized oils were prepared and the release kinetics of magnesium ions from the internal to the external aqueous phase was investigated at T=4°C, for different crystallized lipophilic matrices. All the emulsions were formulated using the same surface-active species, namely polyglycerol polyricinoleate (oil-soluble) and sodium caseinate (water-soluble). The external aqueous phase was a lactose or glucose solution at approximately the same osmotic pressure as that of the inner droplets, in order to avoid osmotic water transfer phenomena. We investigated two types of crystallized lipophilic systems: one based on blends of cocoa butter and miglyol oil, exploring a solid fat content from 0 to 90% and the other system based on milk fat fractions for which the solid fat content varies between 54 and 86%. For double emulsions based on cocoa butter/miglyol oil, the rate of magnesium release was gradually lowered by increasing the % of fat crystals i.e. cocoa butter, in agreement with a diffusion/permeation mechanism. However for double emulsions based on milk fat fractions, the rate of magnesium release was independent of the % of fat crystals and remains the one at t=0. This difference in diffusion patterns, although the solid content is of the same order, suggests a different distribution of fat crystals within the double globules: a continuous fat network acting as a physical barrier for the diffusion of magnesium for double emulsions based on cocoa butter/miglyol oil and double globule/water interfacial distribution for milk fat fractions based double emulsions, through the formation of a crystalline shell allowing an effective protection of the double globules against diffusion of magnesium to the external aqueous phase. Copyright © 2017 Elsevier Inc. All rights reserved.

Effect of long-term water immersion or thermal shock on mechanical properties of high-impact acrylic denture base resins.

Science.gov (United States)

Sasaki, Hirono; Hamanaka, Ippei; Takahashi, Yutaka; Kawaguchi, Tomohiro

2016-01-01

The purpose of this study was to investigate the effect of long-term water immersion or thermal shock on the mechanical properties of high-impact acrylic denture base resins. Two high-impact acrylic denture base resins were selected for the study. Specimens of each denture base material tested were fabricated according to the manufacturers' instructions (n=10). The flexural strength at the proportional limit, the elastic modulus and the impact strength of the specimens were evaluated. The flexural strength at the proportional limit of the high-impact acrylic denture base resins did not change after six months' water immersion or thermocycling 50,000 times. The elastic moduli of the high-impact acrylic denture base resins significantly increased after six months' water immersion or thermocycling 50,000 times. The impact strengths of the high-impact acrylic denture base resins significantly decreased after water immersion or thermocycling as described above.

Modification of natural leather by grafting emulsion copolymerization technique

International Nuclear Information System (INIS)

Badran, A.S.; Nasr, H.E.; El-Halawany, N.R.; Mohamed, W.S.

2005-01-01

Grafting emulsion copolymerization of methyl methacrylate (MMA) with butyl acrylate of different molar ratios onto natural leather with different molar ratios was carried out using developed redox initiation system of potassium persulphate (PPS) as an oxidizing agent and some sodium bisulphite adducts as reducing agent, as well as sodium dodecyl sulphate (SDS) was used as an anionic emulsifier. The grafted leather was characterized via FTIR, SEM and thermal gravimetric analysis. Moreover, the grafted leather was evaluated through water absorption, tensile strength, dyeing performance and hardness measurements. The obtained results revealed that the physical and mechanical properties of the modified leather were enhanced

Radiation curing applications of palm oil acrylates

International Nuclear Information System (INIS)

Mohd Hilmi Mahmood; Khairul Zaman; Rida, Anak Tajau; Mek Zah Salleh; Rosley Che Ismail

2007-01-01

Various palm oil based urethan acrylate prepolymers (UP) were prepared from palm oil based polyols, diisocyanate compounds and hydroxyl terminated acrylate monomers by following procedure derived from established methods. The products were compared with each other in term of their molecular weights (MW), viscosities, curing speed by UV irradiation, gel contents and film hardness. The molecular structure of diisocyanate compounds and hydroxyl acrylate monomers were tend to determine the molecular weights and hence viscosities of the final products of urethan acrylate prepolymers (UP), whereas, the MW of the UP has no direct effects on the UV curing properties of the prepolymers. (author)

Preparation of a Fluorocarbon Polymerizable Surfactant and Its Application in Emulsion Polymerization of Fluorine-Containing Acrylate

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Meng Zhao

2017-11-01

Full Text Available A novel polymerizable fluorocarbon surfactant, perfluoro (4–methyl–3, 6–dioxaoct–7–ene sodium sulfonate (PSVNa, was synthesized and characterized. The fluorocarbon surfactant PSVNa and its mixture PSVNa/SDS were used as emulsifiers during the emulsion polymerization of DFHMA/MMA. The investigation of polymerization kinetics, particle size, and stability of the emulsions revealed that PSVNa has excellent emulsifying properties. The NMR spectrum of the copolymer and the detection of residual PSVNa show that more than 95% of the fluorocarbon surfactants have been linked to the polymer chains by radical polymerization, which will greatly reduce the environmental pollution caused by fluorinated surfactants.

Stability Proxies for Water-in-Oil Emulsions and Implications in Aqueous-based Enhanced Oil Recovery

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Mehrnoosh Moradi

2011-07-01

Full Text Available Several researchers have proposed that mobility control mechanisms can positively contribute to oil recovery in the case of emulsions generated in Enhanced-Oil Recovery (EOR operations. Chemical EOR techniques that use alkaline components or/and surfactants are known to produce undesirable emulsions that create operational problems and are difficult to break. Other water-based methods have been less studied in this sense. EOR processes such as polymer flooding and LoSalTM injection require adjustments of water chemistry, mainly by lowering the ionic strength of the solution or by decreasing hardness. The decreased ionic strength of EOR solutions can give rise to more stable water-in-oil emulsions, which are speculated to improve mobility ratio between the injectant and the displaced oil. The first step toward understanding the connection between the emulsions and EOR mechanisms is to show that EOR conditions, such as salinity and hardness requirements, among others, are conducive to stabilizing emulsions. In order to do this, adequate stability proxies are required. This paper reviews commonly used emulsion stability proxies and explains the advantages and disadvantage of methods reviewed. This paper also reviews aqueous-based EOR processes with focus on heavy oil to contextualize in-situ emulsion stabilization conditions. This context sets the basis for comparison of emulsion stability proxies.

Synthesis of Covalently Cross-Linked Colloidosomes from Peroxidized Pickering Emulsions

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Nadiya Popadyuk

2016-10-01

Full Text Available A new approach to the formation of cross-linked colloidosomes was developed on the basis of Pickering emulsions that were stabilized exclusively by peroxidized colloidal particles. Free radical polymerization and a soft template technique were used to convert droplets of a Pickering emulsion into colloidosomes. The peroxidized latex particles were synthesized in the emulsion polymerization process using amphiphilic polyperoxide copolymers poly(2-tert-butylperoxy-2-methyl-5-hexen-3-ine-co-maleic acid (PM-1-MAc or poly[N-(tert-butylperoxymethylacrylamide]-co-maleic acid (PM-2-MAc, which were applied as both initiators and surfactants (inisurfs. The polymerization in the presence of the inisurfs results in latexes with a controllable amount of peroxide and carboxyl groups at the particle surface. Peroxidized polystyrene latex particles with a covalently grafted layer of inisurf PM-1-MAc or PM-2-MAc were used as Pickering stabilizers to form Pickering emulsions. A mixture of styrene and/or butyl acrylate with divinylbenzene and hexadecane was applied as a template for the synthesis of colloidosomes. Peroxidized latex particles located at the interface are involved in the radical reactions of colloidosomes formation. As a result, covalently cross-linked colloidosomes were obtained. It was demonstrated that the structure of the synthesized (using peroxidized latex particles colloidosomes depends on the amount of functional groups and pH during the synthesis. Therefore, the size and morphology of colloidosomes can be controlled by latex particle surface properties.

Effects of Temperature and pH on Immobilized Laccase Activity in Conjugated Methacrylate-Acrylate Microspheres

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Siti Zulaikha Mazlan

2017-01-01

Full Text Available Immobilization of laccase on the functionalized methacrylate-acrylate copolymer microspheres was studied. Poly(glycidyl methacrylate-co-n-butyl acrylate microspheres consisting of epoxy groups were synthesized using facile emulsion photocuring technique. The epoxy groups in poly(GMA-co-nBA microspheres were then converted to amino groups. Laccase immobilization is based on covalent binding via amino groups on the enzyme surface and aldehyde group on the microspheres. The FTIR spectra showed peak at 1646 cm−1 assigned to the conformation of the polymerization that referred to GMA and nBA monomers, respectively. After modification of the polymer, intensity of FTIR peaks assigned to the epoxy ring at 844 cm−1 and 904 cm−1 was decreased. The results obtained from FTIR exhibit a good agreement with the epoxy content method. The activity of laccase-immobilized microspheres increased upon increasing the epoxy content. Furthermore, poly(GMA-co-nBA microspheres revealed uniform size below 2 µm that contributes to large surface area of the microspheres to be used as a matrix, thus increasing the enzyme capacity and enzymatic reaction. Immobilized enzyme also shifted to higher pH and temperature compared to free enzyme.

Synthesis and Characterization of Solution and Melt Processible Poly(Acrylonitrile-Co-Methyl Acrylate) Statistical Copolymers

Science.gov (United States)

Pisipati, Padmapriya

Polyacrylonitrile (PAN) and its copolymers are used in a wide variety of applications ranging from textiles to purification membranes, packaging material and carbon fiber precursors. High performance polyacrylonitrile copolymer fiber is the most dominant precursor for carbon fibers. Synthesis of very high molecular weight poly(acrylonitrile-co-methyl acrylate) copolymers with weight average molecular weights of at least 1.7 million g/mole were synthesized on a laboratory scale using low temperature, emulsion copolymerization in a closed pressure reactor. Single filaments were spun via hybrid dry-jet gel solution spinning. These very high molecular weight copolymers produced precursor fibers with tensile strengths averaging 954 MPa with an elastic modulus of 15.9 GPa (N = 296). The small filament diameters were approximately 5 im. Results indicated that the low filament diameter that was achieved with a high draw ratio, combined with the hybrid dry-jet gel spinning process lead to an exponential enhancement of the tensile properties of these fibers. Carbon fibers for polymer matrix composites are currently derived from polyacrylonitrile copolymer fiber precursors where solution spinning accounts for ˜40 % of the total fiber production cost. To expand carbon fiber applications into the automotive industry, the cost of the carbon fiber needs to be reduced from 8 to ˜3-5. In order to develop an alternative melt processing route several benign plasticizers have been investigated. A low temperature, persulfate-metabisulfite initiated emulsion copolymerization was developed to synthesize poly(acrylonitrile-co-methyl acrylate) copolymers with acrylonitrile contents between 91-96 wt% with a molecular weight range of 100-200 kg/mol. This method was designed for a potential industrial scale up. Furthermore, water was investigated as a potential melting point depressant for these copolymers. Twenty-five wt% water lead to a decrease in the Tm of a 93/7 wt/wt % poly

Nano ZnO/amine composites antimicrobial additives to acrylic paints

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H.B. Kamal

2015-12-01

Full Text Available Nano ZnO has been widely used as an antimicrobial agent not only for food packaging purposes but also in many coating processes. The present work is meant to enhance such functions through the preparation of sustainable and safe conduct of nano ZnO composites with amine derivatives that are characterized by their antimicrobial and anti-fouling functional activities. The results obtained revealed a more comprehensive approach to the antimicrobial function based on the reported active oxide species role. The oxide/amine composites and the acrylic emulsion paint were characterized chemically and structurally through FT-IR, TGA and TEM supported by biological assessment of each ZnO/amine composite action. Results of the study concluded that equilibrium between the nano ZnO particles size, their dispersion form, and amine ability to stabilize the actively produced oxygen species responsible for the antimicrobial function, should all be accounted for when persistence of antimicrobial agent efficiency is regarded.

Plant oil-based shape memory polymer using acrylic monolith

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T. Tsujimoto

2015-09-01

Full Text Available This article deals with the synthesis of a plant oil-based material using acrylic monolith. An acrylic monolith bearing oxirane groups was prepared via simple technique that involved the dissolution of poly(glycidyl methacrylate-comethyl methacrylate (PGMA in ethanolic – aqueous solution by heating and subsequent cooling. The PGMA monolith had topologically porous structure, which was attributed to the phase separation of the polymer solution. The PGMA monolith was impregnated by epoxidized soybean oil (ESO containing thermally-latent catalyst, and the subsequent curing produced a crosslinked material with relatively good transparency. The Young’s modulus and the tensile strength of polyESO/PGMA increased compared with the ESO homopolymer. The strain at break of polyESO/PGMA was larger than that of the ESO homopolymer and crosslinked PGMA. Furthermore, polyESO/PGMA exhibited good shape memory-recovery behavior.

[Matrix transdermal systems for caffeine delivery based on polymer and emulsion compounds].

Science.gov (United States)

Kuznetsova, E G; Kuryleva, O M; Salomatina, L A; Sevast'ianov, V I

2008-01-01

The goal of this work was to develop and test transdermal therapeutic systems for caffeine delivery. In vitro experiments showed that the rate of caffeine diffusion through untreated rabbit skin from a transdermal therapeutic systems based on polymer compound containing 50 mg medicine was 67.2 (9.1 microg/cm2h; for a system based on emulsion compound it was 173 (19 microg/cm2h. Methods for studying the caffeine release rate and quantitative measurement of caffeine content in the emulsion-based transdermal therapeutic system were developed. These methods are required to obtain data for standard drug documentation. The results of in vivo experiments in rabbits showed the absence of irritating effect of the emulsion-based transdermal therapeutic system. The obtained data on the specific efficiency of the transdermal therapeutic systems for caffeine delivery (50 mg) in healthy volunteers showed that this medicine could be used as a nonnarcotic psychoactivator for improving mental and physical activities and attention concentration.

Gelatin-hydroxypropyl methylcellulose water-in-water emulsions as a new bio-based packaging material.

Science.gov (United States)

Esteghlal, Sara; Niakosari, Mehrdad; Hosseini, Seyed Mohammad Hashem; Mesbahi, Gholam Reza; Yousefi, Gholam Hossein

2016-05-01

Gelatin and hydroxypropyl methylcellulose (HPMC) are two incompatible and immiscible biopolymers which cannot form homogeneous composite films using usual methods. In this study, to prevent phase separation, gelatin-HPMC water-in-water (W/W) emulsion was utilized to from transparent composite films by entrapment the HPMC dispersed droplets in gelatin continuous network. The physicochemical and mechanical properties of emulsion-based films containing different amounts (5-30%) of dispersed phase were determined and compared with those of individual polymer-based films. Incorporating HPMC into W/W emulsion-based films had no significant effect on the tensile strength. The flexibility of composite films decreased at HPMC concentrations below 20%. The depletion layer at the droplets interface reduced the diffusion of water vapor molecules because of its hydrophobic nature, so the water vapor permeability remained constant. Increasing the HPMC content in the emulsion films increased the swelling and decreased the transparency. The entrapment of HPMC in continuous gelatin phase decreased its solubility. Therefore, W/W emulsions are capable of holding two incompatible polymers alongside each other within a homogeneous film network without weakening the physical properties. Copyright © 2016 Elsevier B.V. All rights reserved.

Enzymatically interesterified fats based on mutton tallow and walnut oil suitable for cosmetic emulsions.

Science.gov (United States)

Kowalska, M; Mendrycka, M; Zbikowska, A; Stawarz, S

2015-02-01

Formation of emulsion systems based on interesterified fats was the objective of the study. Enzymatic interesterification was carried out between enzymatic mutton tallow and walnut oil in the proportions 2 : 3 (w/w) to produce fats not available in nature. At the beginning of the interesterification process, the balance between the interesterification and fat hydrolysis was intentionally disturbed by adding more water to the catalyst (Lipozyme IR MR) of the reaction to produce more of the polar fraction monoacylglycerols [MAGs] and diacylglycerols [DAGs]. To obtain a greater quantity of MAGs and DAGs in the reaction environment via hydrolysis, water was added (11, 13, 14, 16 w-%) to the enzymatic preparation. The obtained fats were used to form emulsions. The emulsions were evaluated with respect to sensory and skin moisturizing properties by 83 respondents. Determination of emulsion stability using temperature and centrifugal tests was carried out. Morphology and the type of emulsions were determined. The respondents described the skin to which the emulsions in testing were applied as smooth, pleasant to touch and adequately moisturized. The work has demonstrated that interesterification of a mutton tallow and walnut oil blend resulted in new fats with very interesting characteristics of triacylglycerols that are not present in the environment. The results of the present work indicate the possibility of application of fats with the largest quantity of MAGs and DAGs as a fat base of emulsions in the cosmetic industries. The hypothesis assumed in this work of producing additional quantities of MAGs and DAGs (in the process of enzymatic interesterification) responsible for the stability of the system was confirmed. It should be pointed out that the emulsions based on interesterified fats exhibited a greater level of moisturization of the skin than the emulsions containing non-interesterified fat. Also, in the respondents' opinion, the emulsion containing fat, which

Preparation of nano composite latex of poly(butyl acrylate-co-methyl methacrylate) P (BA-co-MMA) and layered double hydroxide (LDH) by mini emulsion polymerization; Preparacao de latex nanocomposito de poli(acrilato de butila-co-metacrilato de metila) P (BA-co-MMA) e hidroxido duplo lamelar (HDL) por meio da tecnica de polimerizacao em miniemulsao

Energy Technology Data Exchange (ETDEWEB)

Silva, Rodrigo D; Lona, Liliane M.F., E-mail: liliane@feq.unicamp.br [Universidade Estadual de Campinas - Unicamp, Faculdade de Engenharia Quimica, SP (Brazil); Dube, Marc A [Universidade de Ottawa. Departamento de Engenharia Quimica e Biologica, Ottawa, ON (Canada)

2011-07-01

In the present work, the synthesis of polymeric nonconsumption (PNCs) of P(BA-coMMA) and layered LDH through mini emulsion polymerization (MEP) was studied. The commercial organically modified LDH Perkalite F100S was used as filler and octadecyl acrylate (ODA) as costabilizer of the mini emulsions. Two types of surfactant, a cationic and nonionic one, were investigated and the cationic one could not stabilize the system when the LDH was present. The polymerization kinetics was not significantly affected by the presence of LDH which kept the pH of the system constant during the reaction. The dispersion of the inorganic material in the polymeric matrix was evaluated by X-ray diffraction which suggested exfoliation of the LDH. (author)

Creating nanoscale emulsions using condensation.

Science.gov (United States)

Guha, Ingrid F; Anand, Sushant; Varanasi, Kripa K

2017-11-08

Nanoscale emulsions are essential components in numerous products, ranging from processed foods to novel drug delivery systems. Existing emulsification methods rely either on the breakup of larger droplets or solvent exchange/inversion. Here we report a simple, scalable method of creating nanoscale water-in-oil emulsions by condensing water vapor onto a subcooled oil-surfactant solution. Our technique enables a bottom-up approach to forming small-scale emulsions. Nanoscale water droplets nucleate at the oil/air interface and spontaneously disperse within the oil, due to the spreading dynamics of oil on water. Oil-soluble surfactants stabilize the resulting emulsions. We find that the oil-surfactant concentration controls the spreading behavior of oil on water, as well as the peak size, polydispersity, and stability of the resulting emulsions. Using condensation, we form emulsions with peak radii around 100 nm and polydispersities around 10%. This emulsion formation technique may open different routes to creating emulsions, colloidal systems, and emulsion-based materials.

Radiation grafting processes and properties of leathers modified with butyl acrylate

International Nuclear Information System (INIS)

Pietrucha, K.

1982-01-01

Conditions for radiation induced grafting with butyl acrylate dispersed in water emulsion onto chrome-tanned pig skins have been worked out for γ-rays and electron beam irradiations. The highest yield of grafting was observed at monomer concentration approximately 25% (w/w), dose equal to 25 kGy and dose rate not exceeding 10 MGy/h. At these conditions the yield of grafting attained a value approximately 25% and content of homopolymer in the leather amounted to 6%. The efficiency of monomer to polymer conversion decreases when the concentration of monomer in emulsion and dose rate increases. Yield of homopolymer is independent of the dose rate. An explanation of the observed relations has been proposed. The physical and used properties of grafted leathers were tested. Radiation processed leathers were found superior to samples finished by traditional methods. One has to point to better tolerance against chemical cleaning and reduced water take-up without loss of high permeability of water vapour, responsible for good hygienic properties of leather products. Recommendations for industrial scale radiation grafting are given. (author)

[Acrylic resin removable partial dentures

NARCIS (Netherlands)

Baat, C. de; Witter, D.J.; Creugers, N.H.J.

2011-01-01

An acrylic resin removable partial denture is distinguished from other types of removable partial dentures by an all-acrylic resin base which is, in principle, solely supported by the edentulous regions of the tooth arch and in the maxilla also by the hard palate. When compared to the other types of

Steel Protective Coating Based on Plasticized Epoxy Acrylate Formulation Cured by Electron Beam Irradiation

International Nuclear Information System (INIS)

Ibrahim, M.S.; Said, H.M.; Mohamed, I.M.; Mohamed, H.A.; Kandile, N.G.

2011-01-01

Electron beam (EB) was used to cure coatings based on epoxy acrylate oligomer (EA) and different plasticizers such as epoxidized soybean oil, glycerol and castor oil. The effect of irradiation doses (10, 25, 50 kGy) on the curing epoxy acrylate formulations containing plasticizers was studied. In the addition, the effect of the different plasticizers on the end use performance properties of epoxy acrylate coatings such as hardness, bending, adhesion, acid and alkali resistance tests were investigated. It was observed that the incorporation of castor oil in epoxy acrylate, diluted by 1,6 hexandiol diacrylate monomer (HD) with a ratio (EA 70%, HD 20%, castor oil 10%) under the dose 10 kGy improved the physical, chemical and mechanical properties of cured films than the other plasticizers. On the other hand, sunflower free fatty acids were epoxidized in-situ under well established conditions and then was subjected to react with aniline in sealed ampoules under inert atmosphere at 140 degree C. The produced adduct was added at different concentrations to epoxy acrylate coatings under certain EB irradiation dose and then evaluated as corrosion inhibitors for carbon steel surfaces in terms of weight loss measurements and corrosion resistance tests. It was observed that the formula containing 0.4 gm of aniline adduct / 100 gm epoxy acrylate resin gave the best corrosion protection for carbon steel

Features of the incorporation of single and double based powders within emulsion explosives

Science.gov (United States)

Ribeiro, J. B.; Mendes, R.; Tavares, B.; Louro, C.

2014-05-01

In this work, features of the thermal and detonation behaviour of compositions resulting from the mixture of single and double based powders within ammonium nitrate based emulsion explosives are shown. Those features are portrayed through results of thermodynamic-equilibrium calculations of the detonation velocity, the chemical compatibility assessment through differential thermal analysis [DTA] and thermo gravimetric analysis [TGA], the experimental determination of the detonation velocity and a comparative evaluation of the shock sensitivity using a modified version of the "gap-test". DTA/TGA results for the compositions and for the individual components overlap until the beginning of the thermal decomposition which is an indication of the absence of formation of any new chemical species and so of the compatibility of the components of the compositions. After the beginning of the thermal decomposition it can be seen that the rate of mass loss is much higher for the compositions with powder than for the one with sole emulsion explosive. Both, theoretical and experimental, values of the detonation velocity have been shown to be higher for the powdered compositions than for the sole emulsion explosive. Shock sensitivity assessments have ended-up with a slightly bigger sensitivity for the compositions with double based powder when compared to the single based compositions or to the sole emulsion.

Features of the incorporation of single and double based powders within emulsion explosives

International Nuclear Information System (INIS)

Ribeiro, J B; Mendes, R; Tavares, B; Louro, C

2014-01-01

In this work, features of the thermal and detonation behaviour of compositions resulting from the mixture of single and double based powders within ammonium nitrate based emulsion explosives are shown. Those features are portrayed through results of thermodynamic-equilibrium calculations of the detonation velocity, the chemical compatibility assessment through differential thermal analysis [DTA] and thermo gravimetric analysis [TGA], the experimental determination of the detonation velocity and a comparative evaluation of the shock sensitivity using a modified version of the g ap-test . DTA/TGA results for the compositions and for the individual components overlap until the beginning of the thermal decomposition which is an indication of the absence of formation of any new chemical species and so of the compatibility of the components of the compositions. After the beginning of the thermal decomposition it can be seen that the rate of mass loss is much higher for the compositions with powder than for the one with sole emulsion explosive. Both, theoretical and experimental, values of the detonation velocity have been shown to be higher for the powdered compositions than for the sole emulsion explosive. Shock sensitivity assessments have ended-up with a slightly bigger sensitivity for the compositions with double based powder when compared to the single based compositions or to the sole emulsion.

Olive Oil Based Emulsions in Frozen Puff Pastry Production

Science.gov (United States)

Gabriele, D.; Migliori, M.; Lupi, F. R.; de Cindio, B.

2008-07-01

Puff pastry is an interesting food product having different industrial applications. It is obtained by laminating layers of dough and fats, mainly shortenings or margarine, having specific properties which provides required spreading characteristic and able to retain moisture into dough. To obtain these characteristics, pastry shortenings are usually saturated fats, however the current trend in food industry is mainly oriented towards unsatured fats such as olive oil, which are thought to be safer for human health. In the present work, a new product, based on olive oil, was studied as shortening replacer in puff pastry production. To ensure the desired consistency, for the rheological matching between fat and dough, a water-in-oil emulsion was produced based on olive oil, emulsifier and a hydrophilic thickener agent able to increase material structure. Obtained materials were characterized by rheological dynamic tests in linear viscoelastic conditions, aiming to setup process and material consistency, and rheological data were analyzed by using the weak gel model. Results obtained for tested emulsions were compared to theological properties of a commercial margarine, adopted as reference value for texture and stability. Obtained emulsions are characterized by interesting rheological properties strongly dependent on emulsifier characteristics and water phase composition. However a change in process temperature during fat extrusion and dough lamination seems to be necessary to match properly typical dough rheological properties.

Effect of High Pressure Homogenization on the Physicochemical Properties of Natural Plant-based Model Emulsion Applicable for Dairy Products

Science.gov (United States)

Park, Sung Hee; Min, Sang-Gi; Jo, Yeon-Ji; Chun, Ji-Yeon

2015-01-01

In the dairy industry, natural plant-based powders are widely used to develop flavor and functionality. However, most of these ingredients are water-insoluble; therefore, emulsification is essential. In this study, the efficacy of high pressure homogenization (HPH) on natural plant (chocolate or vanilla)-based model emulsions was investigated. The particle size, electrical conductivity, Brix, pH, and color were analyzed after HPH. HPH significantly decreased the particle size of chocolate-based emulsions as a function of elevated pressures (20-100 MPa). HPH decreased the mean particle size of chocolate-based emulsions from 29.01 μm to 5.12 μm, and that of vanilla-based emulsions from 4.18 μm to 2.44 μm. Electrical conductivity increased as a function of the elevated pressures after HPH, for both chocolate- and vanilla-based model emulsions. HPH at 100 MPa increased the electrical conductivity of chocolate-based model emulsions from 0.570 S/m to 0.680 S/m, and that of vanilla-based model emulsions from 0.573 S/m to 0.601 S/m. Increased electrical conductivity would be attributed to colloidal phase modification and dispersion of oil globules. Brix of both chocolate- and vanilla-based model emulsions gradually increased as a function of the HPH pressure. Thus, HPH increased the solubility of plant-based powders by decreasing the particle size. This study demonstrated the potential use of HPH for enhancing the emulsification process and stability of the natural plant powders for applications with dairy products. PMID:26761891

Studies on the antifungal activities of the novel synthesized chelating co-polymer emulsion lattices and their silver complexes

Directory of Open Access Journals (Sweden)

Abd-El-Ghaffar M.A.

2008-01-01

Full Text Available The novel binary chelating co-polymers of butyl acrylate with itaconic and maleic acids were prepared by emulsion polymerization process. The chelating co-polymers of butyl acrylate-co-itaconic acid (BuA/IA and butyl acrylate-co-maleic acid (BuA/MA and their silver complexes were characterized and identified using IR spectroscopy and differential scanning calorimetry (DSC measurements. The biological activities of these compounds were studied against various types of fungal species. The dose and the rate of leached silver ions were controlled by the type of the co-polymers used and the solubility in the medium. The results provided laboratory support for the concept that the polymers containing chemically bound biocide are useful for controlling microbial growth. The silver uptake by strains of different fungal species was studied to determine their difference in behavior to the antifungal activities of these compounds. The uptake strategy was examined by transmission electron microscopy (TEM.

Structured emulsion-based delivery systems: controlling the digestion and release of lipophilic food components.

Science.gov (United States)

McClements, David Julian; Li, Yan

2010-09-15

There is a need for edible delivery systems to encapsulate, protect and release bioactive and functional lipophilic constituents within the food and pharmaceutical industries. These delivery systems could be used for a number of purposes: controlling lipid bioavailability; targeting the delivery of bioactive components within the gastrointestinal tract; and designing food matrices that delay lipid digestion and induce satiety. Emulsion technology is particularly suited for the design and fabrication of delivery systems for lipids. In this article we provide an overview of a number of emulsion-based technologies that can be used as edible delivery systems by the food and other industries, including conventional emulsions, nanoemulsions, multilayer emulsions, solid lipid particles, and filled hydrogel particles. Each of these delivery systems can be produced from food-grade (GRAS) ingredients (e.g., lipids, proteins, polysaccharides, surfactants, and minerals) using relatively simple processing operations (e.g., mixing, homogenizing, and thermal processing). The structure, preparation, and utilization of each type of delivery system for controlling lipid digestion are discussed. This knowledge can be used to select the most appropriate emulsion-based delivery system for specific applications, such as encapsulation, controlled digestion, and targeted release. Copyright 2010 Elsevier B.V. All rights reserved.

Quantitative Analysis of Micro-Structure in Meat Emulsions from Grating-Based Multimodal X-Ray Tomography

DEFF Research Database (Denmark)

Einarsdottir, Hildur; Nielsen, Mikkel Schou; Miklos, Rikke

2013-01-01

Using novel X-ray techniques, based on grating-interferometry, new imaging modalities can be obtained simultaneously with absorption computed tomography (CT). These modalities, called phase contrast and dark field imaging, measure the electron density and the diffusion length of the sample....... Enhanced contrast capabilities of this X-ray technique makes studies on materials with similar attenuation properties possible. In this paper the focus is set on processing grating-based X-ray tomograms of meat emulsions to quantitatively measure micro-structural changes due to heat treatment. The emulsion...... samples were imaged both in a raw and cooked state. Additionally, different fat types were used in the emulsions in order to compare micro-structural differences when either pork fat or sunflower oil was used. From the reconstructed tomograms the different ingredients in the emulsions were segmented using...

Shear force bond analysis between acrylic resin bases and retention framework (open- and mesh-type)

Science.gov (United States)

Royhan, A.; Indrasari, M.; Masulili, C.

2017-08-01

Occlusions between teeth and the activity of the muscles around an artificial tooth during mastication create a force on dentures. This force causes friction between acrylic resin bases and retention frameworks that can lead to the complete loss of the acrylic resin base from the framework. The purpose of this study was to analyze the design of retention frameworks and determine which ones have a better resistance to shear forces in order to prevent the loss of heat cured acrylic resin base (HCARB). Six samples each of open-and mesh-type retention frameworks, both types made of Co-Cr material, and HCARB, were shear tested by means of a universal testing machine. The average shear force required to release the HCARB for mesh-type retention frameworks was 28.84 kgf, and the average for the open-type was 26.52 kgf. There was no significant difference between the shear forces required to remove HCARB from open- and mesh-type retention frameworks.

Automatic read out system for superheated emulsion based neutron detector

International Nuclear Information System (INIS)

Meena, J.P.; Parihar, A.; Vaijapurkar, S.G.; Mohan, Anand

2010-01-01

Full text: Defence Laboratory, Jodhpur (DLJ) has developed superheated emulsion technology for neutron and gamma measurements. The laboratory has attempted to develop reader system to display neutron dose and dose rate based on acoustic technique. The paper presents a microcontroller based automatic reader system for neutron measurements using indigenously developed superheated emulsion detector. The system is designed for real time counting of bubbles formed in superheated emulsion detector. A piezoelectric transducer is used for sensing bubble acoustic. The front end of system is mainly consisting of specially designed signal conditioning unit consisted of piezoelectric transducer, an amplifier, a high-pass filter, a differentiator, a comparator and monostable multivibrator. The system is based on PIC 18F6520 microcontroller having large internal SRAM, 10-bit internal ADC, I 2 C interface, UART/USART modules. The paper also describes the design of following peripheral units interfaced to microcontroller temperature and battery monitoring, display, keypad and a serial communication. The reader system measures and displays neutron dose and dose rate, number of bubble and elapsed time. The developed system can be used for detecting very low neutron leakage in the accelerators, nuclear reactors and nuclear submarines. The important features of system are compact, light weight, cost effective and high neutron sensitivity. The prototype was tested and evaluated by exposing to 241 Am-Be neutron source and results have been reported

New acrylic resin composite with improved thermal diffusivity.

Science.gov (United States)

Messersmith, P B; Obrez, A; Lindberg, S

1998-03-01

Studies have shown that physical characteristics of denture base materials may affect patient acceptance of denture prostheses by altering sensory experience of food during mastication. Thermal diffusivity is one material property that has been cited as being important in determining gustatory response, with denture base acrylic resins having low thermal diffusivity compared with denture base metal alloys. This study prepared and characterized experimental acrylic resin composite material with increased thermal diffusivity. Sapphire (Al2O3) whiskers were added to conventional denture base acrylic resin during processing to achieve loadings of 9.35% and 15% by volume. Cylindrical test specimens containing an embedded thermocouple were used to determine thermal diffusivity over a physiologic temperature range (0 degree to 70 degrees C). Thermal diffusivities of the sapphire containing composites were found to be significantly higher than the unmodified acrylic resin. Thermal diffusivity was found to increase in proportion to the volume percentage of sapphire filler, which suggested that the high aspect ratio ceramic particles formed a pathway for heat conduction through the insulating polymer matrix. The thermal diffusivity of denture base acrylic resin was increased by the addition of thermally conducting sapphire whiskers.

Preparation and magnetic properties of polymer magnetic composites based on acrylate resin filled with nickel plating graphite nanosheets

Energy Technology Data Exchange (ETDEWEB)

Zhang Yi, E-mail: zhangyi520love@yahoo.com.cn [Department of Applied Chemistry, School of Science, Northwestern Polytechnical University, Xi' an 710072 (China); Qi Shuhua; Zhang Fan; Yang Yongqing; Duan Guochen [Department of Applied Chemistry, School of Science, Northwestern Polytechnical University, Xi' an 710072 (China)

2011-11-01

Nickel plating graphite nanosheets (Ni/GNs) were prepared by electroless plating method using graphite nanosheets (GNs). Then a novel polymer magnetic composites based on acrylate pressure-sensitive adhesive (acrylate PSA) filled with Ni/GNs were fabricated by solution blend method. The Ni/GNs and acrylate PSA/Ni/GNs composites were characterized by scanning electron microscope (SEM)/energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), vibrating sample magnetometer (VSM) and transmission electron microscope (TEM). All results showed that relatively uniform and compact Ni layer is successfully coated onto GNs under the given conditions, furthermore, Ni/GNs are homogeneously dispersed in acrylate PSA. The VSM results showed that the saturation magnetization of acrylate PSA/Ni/GNs composites increases with an increasing content of Ni/GNs while the coercivity decreases with an increasing content of Ni/GNs. When the content of GNs is 20 wt%, acrylate PSA/Ni/GNs composites exhibites good mechanical properties.

Preparation and magnetic properties of polymer magnetic composites based on acrylate resin filled with nickel plating graphite nanosheets

International Nuclear Information System (INIS)

Zhang Yi; Qi Shuhua; Zhang Fan; Yang Yongqing; Duan Guochen

2011-01-01

Nickel plating graphite nanosheets (Ni/GNs) were prepared by electroless plating method using graphite nanosheets (GNs). Then a novel polymer magnetic composites based on acrylate pressure-sensitive adhesive (acrylate PSA) filled with Ni/GNs were fabricated by solution blend method. The Ni/GNs and acrylate PSA/Ni/GNs composites were characterized by scanning electron microscope (SEM)/energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), vibrating sample magnetometer (VSM) and transmission electron microscope (TEM). All results showed that relatively uniform and compact Ni layer is successfully coated onto GNs under the given conditions, furthermore, Ni/GNs are homogeneously dispersed in acrylate PSA. The VSM results showed that the saturation magnetization of acrylate PSA/Ni/GNs composites increases with an increasing content of Ni/GNs while the coercivity decreases with an increasing content of Ni/GNs. When the content of GNs is 20 wt%, acrylate PSA/Ni/GNs composites exhibites good mechanical properties.

Kinetics of Waterborne Alkyd/Acrylic Hybrid Resin Free Radical Polymerization by Two Systems of Redox and Thermal Initiators

OpenAIRE

shirin Madadi; ali akbar Yousefi; elham Keshmirizadeh

2012-01-01

Kinetics of radical polymerizations of waterborne alkyd/acrylic hybrid resin via batch mini-emulsion technique was studied using redox initiators (TBHP/Fe2+/EDTA/AsAc  and  TBHP/Fe2+/EDTA/SFS) at relatively low temperatures and thermal initiators (BPO, KPS and AIBN) at higher temperatures to seek the most suitable initiator system. At the end of all reactions the unreacted monomer content was reduced using post-polymerization technique; consequently, leading to increased monomer conversion an...

Effect of structure and molecular weight on properties of pressure sensitive adhesives (PSA) formulated from palm oil based urethane acrylate (POBUA)

International Nuclear Information System (INIS)

Mohd Hilmi Mahmood; Shahrol Najmin Baharom; Rida Tajau; Mek Zah Salleh; Khairul Zaman Mohd Dahlan; Rosley Che Ismail

2004-01-01

Various palm oil (RBD Palm Olein) based urethane acrylate prepolymers (UPs) having different structures and molecular weight were synthesized from palm oil based polyols, diisocyanate compounds and hydroxyl terminated acrylate monomers by following established synthesis procedures described elsewhere. The products (UPs) were compared with each other in term of their molecular weight (MW), viscosities and UV curing performances of pressure sensitive adhesives (PSA) UP based formulations. The molecular structure of diisocyanate compounds and hydroxyl acrylate monomers tend to determine the molecular weight and hence viscosities of the final products of urethane acrylate prepolymers (UP), whereas, the MW of the UP has no direct effects on the coatings and adhesive properties of UV curable UP based PSA. (Author)

Synthesis and Properties of IPN Hydrogels Based on Konjac Glucomannan and Poly(acrylic acid)

Institute of Scientific and Technical Information of China (English)

Bing LIU; Zhi Lan LIU; Ren Xi ZHUO

2006-01-01

Novel interpenetrating polymer network (IPN) hydrogels based on konjac glucomannan (KGM) and poly(acrylic acid) (PAA) were prepared by polymerization and cross-linking of acrylic acid (AA) in the pre-fabricated KGM gel. The IPN gel was analyzed by FT-IR. The studies on the equilibrium swelling ratio of IPN hydrogels revealed their sensitive response to environmental pH value. The results of in vitro degradation showed that the IPN hydrogels retain the enzymatic degradation character of KGM.

Novel epoxy-benzoxazine water-based emulsions with reactive benzoxazine surfactants for coatings

Directory of Open Access Journals (Sweden)

M. Krajnc

2014-08-01

Full Text Available Novel epoxy-benzoxazine emulsions designed for water-based coatings were prepared and investigated. Bisphenol A-based epoxy resins with molar weights of 340, 377 and 1750 g/mol along with epoxidized soybean oil were emulsified using mono- and bi-functional benzoxazine surfactants, which are able to react with epoxy resins at their cure temperature. The structure of synthesized surfactants carrying one or two polyether chains was confirmed using Fourier transform infrared spectroscopy, 1H nuclear magnetic resonance and differential scanning calorimetry. Stability of emulsions was verified by particle diameters measurements. Coatings, made directly from emulsions, were dried and cured at elevated temperature using 3,3'-dimetoxybenzidine as curing agent to ensure a highly cross-linked structure of thermosetting films. Curing process, thermal properties and hardness of cured films were investigated. It was found that benzoxazine molecules were well incorporated into the epoxy network upon curing, which ensures no void structure of cured copolymer and enhanced coating properties.

The potential applications in heavy oil EOR with the nanoparticle and surfactant stabilized solvent-based emulsion

Energy Technology Data Exchange (ETDEWEB)

Qiu, F. [Texas A and M Univ., College Station, TX (United States)

2010-07-01

The main challenges in developing the heavy oil reservoirs in the Alaska North Slope (ANS) include technical challenges regarding thermal recovery; sand control and disposal; high asphaltene content; and low in-situ permeability. A chemical enhanced oil recovery method may be possible for these reservoirs. Solvent based emulsion flooding provides mobility control; oil viscosity reduction; and in-situ emulsification of heavy oil. This study evaluated the potential application of nano-particle-stabilized solvent based emulsion injection to enhance heavy oil recovery in the ANS. The optimized micro-emulsion composition was determined using laboratory tests such as phase behaviour scanning, rheology studies and interfacial tension measurements. The optimized nano-emulsions were used in core flooding experiments to verify the recovery efficiency. The study revealed that the potential use of this kind of emulsion flooding is a promising enhanced oil recovery process for some heavy oil reservoirs in Alaska, Canada and Venezuela. 4 refs., 2 tabs., 10 figs.

Preparation, characterization, and antibacterial activity studies of silver-loaded poly(styrene-co-acrylic acid) nanocomposites.

Science.gov (United States)

Song, Cunfeng; Chang, Ying; Cheng, Ling; Xu, Yiting; Chen, Xiaoling; Zhang, Long; Zhong, Lina; Dai, Lizong

2014-03-01

A simple method for preparing a new type of stable antibacterial agent was presented. Monodisperse poly(styrene-co-acrylic acid) (PSA) nanospheres, serving as matrices, were synthesized via soap-free emulsion polymerization. Field-emission scanning electron microscopy micrographs indicated that PSA nanospheres have interesting surface microstructures and well-controlled particle size distributions. Silver-loaded poly(styrene-co-acrylic acid) (PSA/Ag-NPs) nanocomposites were prepared in situ through interfacial reduction of silver nitrate with sodium borohydride, and further characterized by transmission electron microscopy and X-ray diffraction. Their effects on antibacterial activity including inhibition zone, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and bactericidal kinetics were evaluated. In the tests, PSA/Ag-NPs nanocomposites showed excellent antibacterial activity against both gram-positive Staphylococcus aureus and gram-negative Escherichia coli. These nanocomposites are considered to have potential application in antibacterial coatings on biomedical devices to reduce nosocomial infection rates. Copyright © 2013 Elsevier B.V. All rights reserved.

Preparation of Photoresponsive Functionalized Acrylic Nanoparticles Cantaining Carbazole Groups for Smart Cellulosic Papers

Directory of Open Access Journals (Sweden)

Jaber Keyvan Rad

2017-11-01

Full Text Available Photoresponsive functionalized polymer nanoparticles were prepared as useful materials for preparation of smart papers. Such polymer nanoparticles have wide applications in several fields including papers, sensors, bioimaging and biomedicine. First, carbazole as a photosensitive compound was modified with 2-bromoethanol through substitution nucleation reaction to its hydroxyl derivative (N-(2-hydroxyethyl carbazole, CzEtOH. The synthesis of 2-N-carbazolylethyl acrylate (CzEtA monomer was carried out by modification reaction of CzEtOH with acryloyl chloride and the chemical structures of the products were characterized. Next, CzEtA, methyl methacrylate (MMA and butyl acrylate were copolymerized to prepare photoresponsive functionalized polymer nanoparticles through mini-emulsion polymerization in order to form a hydrophobic core. This was followed by copolymerization of MMA and glycidyl methacrylate by seeded emulsion polymerization to give a functionalized outer layer on the latex particles. Absorption characteristics, size, size distribution (narrow size distribution and morphology of the nanoparticles were studied by ultraviolet-visible (UV-Vis spectroscopy, dynamic laser light scattering (DLS analysis and scanning electron microscopy (SEM micrographs, respectively. Finally, due to the importance of photoresponsive smart papers and their wide applications, cellulosic fibers were reacted with the prepared functionalized latex particles for preparation of smart papers. Morphology of the fibers was investigated with respect to the surface-immobilized polymers on the cellulosic paper and their smart behavior was evaluated by UV irradiation at 254 nm. The results revealed fast color changes and the obtained cellulosic papers became violet upon irradiation. This work shows some promising feature of these materials for preparation of anti-counterfeiting papers, where the safety becomes a major concern.

Hydrophilic Surface Modification of PDMS Microchannel for O/W and W/O/W Emulsions

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Shazia Bashir

2015-09-01

Full Text Available A surface modification method for bonded polydimethylsiloxane (PDMS microchannels is presented herein. Polymerization of acrylic acid was performed on the surface of a microchannel using an inline atmospheric pressure dielectric barrier microplasma technique. The surface treatment changes the wettability of the microchannel from hydrophobic to hydrophilic. This is a challenging task due to the fast hydrophobic recovery of the PDMS surface after modification. This modification allows the formation of highly monodisperse oil-in-water (O/W droplets. The generation of water-in-oil-in-water (W/O/W double emulsions was successfully achieved by connecting in series a hydrophobic microchip with a modified hydrophilic microchip. An original channel blocking technique to pattern the surface wettability of a specific section of a microchip using a viscous liquid comprising a mixture of honey and glycerol, is also presented for generating W/O/W emulsions on a single chip.

Rheology of unstable mineral emulsions

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Sokolović Dunja S.

2013-01-01

Full Text Available In this paper, the rheology of mineral oils and their unstable water emulsion were investigated. The oil samples were domestic crude oil UA, its fractions UA1, UA4 and blend semi-product UP1, while the concentration of oil in water emulsions was in the range from 1 up to 30%. The results were analyzed based on shear stress. The oil samples UA, UA1 and UP1 are Newtonian fluids, while UA4 is pseudoplastic fluid. The samples UA and UA4 show higher value of shear stress (83.75 Pa, 297 Pa, then other two samples UA1 and UP1 (18.41 Pa, 17.52 Pa. Rheology of investigated oils due to its complex chemical composition should be analyzed as a simultaneous effect of all their components. Therefore, structural composition of the oils was determined, namely content of paraffins, naphthenes, aromatics and asphaltenes. All samples contain paraffins, naphthenes and aromatics but only oils UA and UA4 contain asphaltenes as well. All investigated emulsions except 30% EUA4 are Newtonian fluids. The EUA4 30% emulsion shows pseudoplastic behaviour, and it is the only 30% emulsion among investigated ones that achieves lower shear stress then its oil. The characteristics of oil samples that could have an influence on their properties and their emulsion rheology, were determined. These characteristics are: neutralization number, interfacial tension, dielectric constant, and emulsivity. Oil samples UA and UA4 have significantly higher values of neutralization number, dielectric constants, and emulsivity. The sample UA has the lowest value of interface tension and the greatest emulsivity, indicating that this oil, among all investigated, has the highest preference for building emulsion. This could be the reason why 20% and 30% emulsions of the oil UA achieve the highest shear stress among all investigated emulsions.

Synthesis and characterization of nano-SiO{sub 2} modified fluorine-containing polyacrylate emulsifier-free emulsion

Energy Technology Data Exchange (ETDEWEB)

Zhou, Jianhua, E-mail: zhoujianh@21cn.com [College of Resource and Environment, Shaanxi University of Science and Technology, Xi’an 710021 (China); Shaanxi Research Institute of Agricultural Products Processing Technology, Xi’an 710021 (China); Chen, Xin; Duan, Hao; Ma, Jianzhong; Ma, Yurong [College of Resource and Environment, Shaanxi University of Science and Technology, Xi’an 710021 (China)

2015-03-15

Graphical abstract: Nano-SiO{sub 2} modified fluorine-containing polyacrylate emulsifier-free emulsion was synthesized by emulsifier-free emulsion polymerization and sol–gel process using ethyl silicate as precursor for nano-SiO{sub 2}. - Highlights: • Nano-SiO{sub 2} modified fluorine-containing polyacrylate emulsifier-free emulsion was successfully synthesized by emulsion polymerization using surfmer and sol–gel process. • The contact angle results showed that the finished fabric had an excellent water and oil repellency. • The nano-SiO{sub 2} modified fluorine-containing polyacrylate emulsifier-free emulsion proved to be highly solvent-resistant and water-resistant. • The transmission electron microscopy (TEM) indicated that the nano-SiO{sub 2} presented on the surface of latex particles. • The atomic force microscope (AFM) and energy dispersive X-ray spectrometer (EDX) confirmed that the hybrid film had a rough surface and the organic fluorine segment could migrate onto the film–air interface. - Abstract: Nano-SiO{sub 2} modified fluorine-containing polyacrylate emulsifier-free emulsion, consisting of methyl methacrylate, butyl acrylate, dodecafluoroheptyl methacrylate and ethyl silicate, was successfully synthesized by emulsion polymerization using surfmer and sol–gel process. When increasing ethyl silicate content, the latex centrifugal stability decreased, and the latex particle size increased. The contact angle results showed that the finished fabric had an excellent water and oil repellency. Furthermore, compared with fluorine-containing polyacrylate emulsifier-free emulsion, the obtained nano-SiO{sub 2} modified fluorine-containing polyacrylate emulsifier-free emulsion proved to be highly solvent-resistant and water-resistant. In addition, the transmission electron microscopy (TEM) indicated that the nano-SiO{sub 2} presented on the surface of latex particles. The atomic force microscope (AFM) and energy dispersive X-ray spectrometer

Dynamical mechanical analysis of photocrosslinked hyperbranched urethane acrylates

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BRANKO DUNJIC

2004-06-01

Full Text Available A series of acrylate functionalized samples based on hyperbranched hydroxy-terminated polyesters with different molecular weights and different degrees of acrylation were synthesized. The obtained urethane acrylates were slightly yellow viscose liquids. Their composition was characterized by FTIR and 1H-NMR spectroscopy and their molecular weights were measured by GPC. All the synthesized samples were diluted with 25 wt.% 1,4-butanediol dimethacrylate (BDDM. The rheological properties of the uncured samples and the dynamic mechanical properties of the UV cured samples were examined. All the samples exhibit Newtonian behavior, which indicates the absence of physical entanglements in these polymers. The viscosity increases with increasing number of acrylic groups per molecule. The glass transition temperature of the UV cured samples increases with increasing the number of acrylic groups per molecule. The value of the storage modulus in the rubber-elastic plateau and the cross-link density increase with increasing number of acrylic groups per molecule. The formed networks are inhomogeneous and the residual unsaturation is the highest in the samples with the largest number of acrylic groups per molecule.

Perubahan warna basis akrilik setelah penggunaan pasta pembersih gigitiruan rosella (The changes of acrylic base color after using roselle pasta denture cleanser)

OpenAIRE

Evan G. Tunggal; Moh. Dharmautama; Eri H. Jubhari

2015-01-01

This clinical experimental study was aimed to determine the effect of roselle denture cleanser paste usage on acrylic base color degradation. Acrylic base color degradation was assessed by providing roselle denture cleanser to 5 subjects to be used every day. In month 3, 6 and 9, data collection were performed by a professional photographer and assessed by CIELab system. Data were analyzed using Wilcoxon and friedman two ways. Acrylic base color, before and after pasta using, show...

Organic Based Glutinous Corn (Zea maize Supplemented With Seaweeds Emulsion

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Jayrome S. Butay

2017-11-01

Full Text Available The study was therefore design to generate scientific information that are vital for organic farming advocates as it uses natural organic farm inputs in the production of corn. It was conducted because of the insurmountable rising cost of inorganic fertilizers perspective the farmers have to look for alternative measures to sustain the profitability of their farming business by evaluating the efficacy of seaweeds emulsion (Carrageenan as nutrient supplement to organic fertilizer on glutinous corn production, a study was conducted at the Cagayan State University – Lal-lo, Cagayan from July 17 to September 25, 2016with the following treatments: T1- Control, T2 – 3 tons Organic Fertilizer, T3 - 1.5 liters Seaweeds Emulsion ha-1 , T4 - 3 liters Seaweeds Emulsion ha-1 , T5 - 4.5 liters Seaweeds Emulsion ha-1 and T6 - 6 liters Seaweeds Emulsion ha-1 arranged in Randomized Complete Block Design with three replications. The treatments have no significant effect on plant height. Application of seaweed emulsion affected the grain development as manifested by longer and heavier corn ear. Higher rates (3-6 li ha-1 proved to more efficient as indicated by the bigger ear, highest yield and ROI of 909.62 percent. The study revealed that 3 tons Organic Fertilizer with liters of seaweed emulsion improved glutinous corn production. Further study is recommended to validate the result and come up with a more reliable conclusion.

Development of High Sensitivity Nuclear Emulsion and Fine Grained Emulsion

Science.gov (United States)

Kawahara, H.; Asada, T.; Naka, T.; Naganawa, N.; Kuwabara, K.; Nakamura, M.

2014-08-01

Nuclear emulsion is a particle detector having high spacial resolution and angular resolution. It became useful for large statistics experiment thanks to the development of automatic scanning system. In 2010, a facility for emulsion production was introduced and R&D of nuclear emulsion began at Nagoya university. In this paper, we present results of development of the high sensitivity emulsion and fine grained emulsion for dark matter search experiment. Improvement of sensitivity is achieved by raising density of silver halide crystals and doping well-adjusted amount of chemicals. Production of fine grained emulsion was difficult because of unexpected crystal condensation. By mixing polyvinyl alcohol (PVA) to gelatin as a binder, we succeeded in making a stable fine grained emulsion.

Development of High Sensitivity Nuclear Emulsion and Fine Grained Emulsion

International Nuclear Information System (INIS)

Kawahara, H.; Asada, T.; Naka, T.; Naganawa, N.; Kuwabara, K.; Nakamura, M.

2014-01-01

Nuclear emulsion is a particle detector having high spacial resolution and angular resolution. It became useful for large statistics experiment thanks to the development of automatic scanning system. In 2010, a facility for emulsion production was introduced and R and D of nuclear emulsion began at Nagoya university. In this paper, we present results of development of the high sensitivity emulsion and fine grained emulsion for dark matter search experiment. Improvement of sensitivity is achieved by raising density of silver halide crystals and doping well-adjusted amount of chemicals. Production of fine grained emulsion was difficult because of unexpected crystal condensation. By mixing polyvinyl alcohol (PVA) to gelatin as a binder, we succeeded in making a stable fine grained emulsion

Features of the Valorization of Single and Double Based Powders for Codetonation in Emulsion Explosives

Science.gov (United States)

Ribeiro, Jose; Mendes, Ricardo; Tavares, Bruno; Louro, Cristina

2013-06-01

In this work, features of the thermal and detonation behavior of compositions resulting from the mixture of single and double based gun powder within ammonium nitrate (AN) based emulsion explosives are shown. That includes results of thermodynamic-equilibrium calculations of the detonation velocity, the chemical compatibility assessment through differential scanning calorimetry [DSC] and thermo gravimetric analysis [TGA], the experimental determination of the detonation velocity and a comparative evaluation of the shock sensitivity using a modified version of the ``gap-test''. DSC/TGA results for the compositions and for the individual components overlap until the beginning of the thermal decomposition which is an indication of the absence of formation of any new chemical specimens and so of the capability of the composition components. After the beginning of the thermal decomposition it can be seen that the rate of mass loss is much higher for the compositions with gun powder than for the sole emulsion explosive. Both, theoretical and experimental, values of the detonation velocity have shown to be higher for the powdered compositions than for the pure emulsion explosive. Shock sensitivity assessment have ended-up with a slightly bigger sensitivity for the compositions with double based gun powder when compared to the single based compositions or to the pure emulsion.

Artificial saliva effect on toxic substances release from acrylic resins

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Kostić Milena

2015-01-01

Full Text Available Background/Aim. Acrylic-based resins are intensively used in dentistry practice as restorative or denture-base materials. The purpose of this study was to analyze the surface structure of denture base resins and the amount of released potentially toxic substances (PTS immediately upon polymerization and incubation in different types of artificial saliva. Methods. Storage of acrylic samples in two models of artificial saliva were performed in a water bath at the temperature of 37 ± 1°C. Analysis of the surface structure of samples was carried out using scanning electronic microscopy analysis immediately after polymerization and after the 30-day incubation. The amounts of PTS per day, week and month extracts were measured using high-pressure liquid chromatography. Results. Surface design and amount of PTS in acrylic materials were different and depended on the types and duration of polymerization. The surfaces of tested acrylates became flatter after immersing in solutions of artificial saliva. The degree of acrylic materials release was not dependent on the applied model of artificial saliva. Conclusion. In order to improve biological features of acrylic resin materials, it was recommended that dentures lined with soft or hard coldpolymerized acrylates should be kept at least 1 to 7 days in water before being given to a patient. So, as to reach high degree of biocompatibility preparation of prosthetic restorations from heat-polymerized acrylate was unnecessary. [Projekat Ministarstva nauke Republike Srbije, br. 41017

Self-assembly formation of palm-based esters nano-emulsion: A molecular dynamics study

Science.gov (United States)

Abdul Rahman, Mohd. Basyaruddin; Huan, Qiu-Yi; Tejo, Bimo A.; Basri, Mahiran; Salleh, Abu Bakar; Rahman, Raja Noor Zaliha Abdul

2009-10-01

Palm-oil esters (POEs) are unsaturated and non-ionic esters that can be prepared by enzymatic synthesis from palm oil. Their nano-emulsion properties possess great potential to act as drug carrier for transdermal drug delivery system. A ratio of 75:5:20 (water/POEs/Span20) was chosen from homogenous region in the phase diagram of our previous experimental work to undergo molecular dynamics simulation. A 15 ns molecular dynamics simulation of nano-emulsion system (water/POEs/Span20) was carried out using OPLS-AA force field. The aggregations of the oil and surfactant molecules are observed throughout the simulation. After 8 ns of simulation, the molecules start to aggregate to form one spherical micelle where the POEs molecules are surrounded by the non-ionic surfactant (Span20) molecules with an average size of 4.2 ± 0.05 nm. The size of the micelle and the ability of palm-based nano-emulsion to self-assemble suggest that this nano-emulsion can potentially use in transdermal drug delivery system.

Technology of Anticorrosive Protection of Steel Constructions by Coatings Based on Rapid-Hardening Bitumen-Latex Emulsion

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Nykyforchyn, H.M.

2016-01-01

Full Text Available The recipes of rapid-hardening bitumen-latex emulsions and coatings on its base are created, in-laboratory tests of their physical, chemical and anticorrosive properties are carried out. The technology of anticorrosive protection and the installation technical documentation for making of aqueous bitumen-latex emulsion is developed, installation is mounted and a pilot lot of rapid-hardening emulsion is produced. Experimental-industrial approbation of the technology of coating formation on pipes in oil and gas industry is carried out.

Experimental study of solvent-based emulsion injection to enhance heavy oil recovery in Alaska North Slope area

Energy Technology Data Exchange (ETDEWEB)

Qiu, F.; Mamora, D. [Texas A and M Univ., College Station, TX (United States)

2010-07-01

This study examined the feasibility of using a chemical enhanced oil recovery method to overcome some of the technical challenges associated with thermal recovery in the Alaska North Slope (ANS). This paper described the second stage research of an experimental study on nano-particle and surfactant-stabilized solvent-based emulsions for the ANS area. Four successful core flood experiments were performed using heavy ANS oil. The runs included water flooding followed by emulsion flooding; and pure emulsion injection core flooding. The injection rate and core flooding temperature remained constant and only 1 PV micro-emulsion was injected after breakthrough under water flooding or emulsion flooding. Oil recovery increased by 26.4 percent from 56.2 percent original oil in place (OOIP) with waterflooding to 82.6 percent OOIP with injection of emulsion following water flooding. Oil recovery was slightly higher with pure emulsion flooding, at 85.8 percent OOIP. The study showed that low permeability generally resulted in a higher shear rate, which is favourable for in-situ emulsification and higher displacement efficiency. 11 refs., 4 tabs., 20 figs.

Acrylate Systemic Contact Dermatitis.

Science.gov (United States)

Sauder, Maxwell B; Pratt, Melanie D

2015-01-01

Acrylates, the 2012 American Contact Dermatitis Society allergen of the year, are found in a range of products including the absorbent materials within feminine hygiene pads. When fully polymerized, acrylates are nonimmunogenic; however, if not completely cured, the monomers can be potent allergens.A 28-year-old woman is presented, who had her teeth varnished with Isodan (Septodont, Saint-Maur-des-Fossés, France) containing HEMA (2-hydroxyethyl methacrylate) with no initial reaction. Approximately 1 month later, the patient developed a genital dermatitis secondary to her feminine hygiene pads. The initial reaction resolved, but 5 months later, the patient developed a systemic contact dermatitis after receiving a second varnishing.The patient was dramatically patch test positive to many acrylates. This case demonstrates a reaction to likely unpolymerized acrylates within a feminine hygiene pad, as well as broad cross-reactivity or cosensitivity to acrylates, and possibly a systemic contact dermatitis with systemic re-exposure to unpolymerized acrylates.

Dairy-Based Emulsions: Viscosity Affects Fat Difference Thresholds and Sweetness Perception.

Science.gov (United States)

Zahn, Susann; Hoppert, Karin; Ullrich, Franziska; Rohm, Harald

2013-11-27

In complex emulsions, viscosity or viscosity-associated sensory attributes such as creaminess are important for quality assessment and product differentiation. Two sets of emulsions with fat or locust bean gum content being varied at seven levels were developed; the two emulsions at each level had similar apparent viscosity. Additionally, sugar concentration was kept constant either with respect to total emulsion, or with respect to the aqueous phase. Series of two-alternative forced choice tests were performed with one constant stimulus, and just noticeable differences were calculated using probability regression. The results show that, when viscosity was not compensated, it was easy for the subjects to (a) distinguish emulsions with different fat content when the fat content was addressed in the question, and to (b) distinguish emulsions with different fat or locust bean gum content when creaminess was addressed. For the latter descriptor, it is of minor importance whether viscosity is altered by fat content or a thickener. Weber fractions that were calculated for viscosity were approximately 0.20. The quantitative effects of viscosity on sweetness, however, depend on how product rheology was modified.

Fat emulsions based on structured lipids (1,3-specific triglycerides): an investigation of the in vivo fate.

Science.gov (United States)

Hedeman, H; Brøndsted, H; Müllertz, A; Frokjaer, S

1996-05-01

Structured lipids (1,3-specific triglycerides) are new chemical entities made by enzymatic transesterification of the fatty acids in the 1,3 positions of the triglyceride. The purpose of this study is to characterize structured lipids with either short chain fatty acids or medium chain fatty acids in the 1,3 positions with regard to their hydrophobicity, and investigate the in vivo fate in order to evaluate the potential of structured lipids as core material in fat emulsions used as parenteral drug delivery system. The lipids were characterized by employing reversed phase high performance liquid chromatography. The biodistribution of radioactively labeled emulsions was studied in rats. By employing high performance liquid chromatography a rank order of the hydrophobicities of the lipids could be given, with the triglycerides containing long chain fatty acids being the most hydrophobic and the structured lipid with short chain fatty acids in the 1,3 positions the least. When formulated as fat emulsions, the emulsion based on structured lipids with short fatty acids in the 1,3 positions was removed slower from the general blood circulation compared to emulsions based on lipids with long chain fatty acids in the 1,3 positions. The type of core material influences the in vivo circulation time of fat emulsions.

Emulsion-Based RIR-MAPLE Deposition of Conjugated Polymers: Primary Solvent Effect and Its Implications on Organic Solar Cell Performance.

Science.gov (United States)

Ge, Wangyao; Li, Nan K; McCormick, Ryan D; Lichtenberg, Eli; Yingling, Yaroslava G; Stiff-Roberts, Adrienne D

2016-08-03

Emulsion-based, resonant infrared matrix-assisted pulsed laser evaporation (RIR-MAPLE) has been demonstrated as an alternative technique to deposit conjugated polymer films for photovoltaic applications; yet, a fundamental understanding of how the emulsion target characteristics translate into film properties and solar cell performance is unclear. Such understanding is crucial to enable the rational improvement of organic solar cell (OSC) efficiency and to realize the expected advantages of emulsion-based RIR-MAPLE for OSC fabrication. In this paper, the effect of the primary solvent used in the emulsion target is studied, both experimentally and theoretically, and it is found to determine the conjugated polymer cluster size in the emulsion as well as surface roughness and internal morphology of resulting polymer films. By using a primary solvent with low solubility-in-water and low vapor pressure, the surface roughness of deposited P3HT and PCPDTBT polymer films was reduced to 10 nm, and the efficiency of P3HT:PC61BM OSCs was increased to 3.2% (∼100 times higher compared to the first MAPLE OSC demonstration [ Caricato , A. P. ; Appl. Phys. Lett. 2012 , 100 , 073306 ]). This work unveils the mechanism of polymer film formation using emulsion-based RIR-MAPLE and provides insight and direction to determine the best ways to take advantage of the emulsion target approach to control film properties for different applications.

Effect of different solutions on color stability of acrylic resin-based dentures

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Marcelo Coelho Goiato

2014-01-01

Full Text Available The aim of this study was to evaluate the effect of thermocycling and immersion in mouthwash or beverage solutions on the color stability of four different acrylic resin-based dentures (Onda Cryl, OC; QC20, QC; Classico, CL; and Lucitone, LU. The factors evaluated were type of acrylic resin, immersion time, and solution (mouthwash or beverage. A total of 224 denture samples were fabricated. For each type of resin, eight samples were immersed in mouthwashes (Plax-Colgate, PC; Listerine, LI; and Oral-B, OB, beverages (coffee, CP; cola, C; and wine, W, and artificial saliva (AS; control. The color change (DE was evaluated before (baseline and after thermocycling (T1, and after immersion in solution for 1 h (T2, 3 h (T3, 24 h (T4, 48 h (T5, and 96 h (T6. The CIE Lab system was used to determine the color changes. The thermocycling test was performed for 5000 cycles. Data were submitted to three-way repeated-measures analysis of variance and Tukey's test (p < 0.05. When the samples were immersed in each mouthwash, all assessed factors, associated or not, significantly influenced the color change values, except there was no association between the mouthwash and acrylic resin. Similarly, when the samples were immersed in each beverage, all studied factors influenced the color change values. In general, regardless of the solution, LU exhibited the greatest DE values in the period from T1 to T5; and QC presented the greatest DE values at T6. Thus, thermocycling and immersion in the various solutions influenced the color stability of acrylic resins and QC showed the greatest color alteration.

Effect of different solutions on color stability of acrylic resin-based dentures.

Science.gov (United States)

Goiato, Marcelo Coelho; Nóbrega, Adhara Smith; dos Santos, Daniela Micheline; Andreotti, Agda Marobo; Moreno, Amália

2014-01-01

The aim of this study was to evaluate the effect of thermocycling and immersion in mouthwash or beverage solutions on the color stability of four different acrylic resin-based dentures (Onda Cryl, OC; QC20, QC; Classico, CL; and Lucitone, LU). The factors evaluated were type of acrylic resin, immersion time, and solution (mouthwash or beverage). A total of 224 denture samples were fabricated. For each type of resin, eight samples were immersed in mouthwashes (Plax-Colgate, PC; Listerine, LI; and Oral-B, OB), beverages (coffee, CP; cola, C; and wine, W), and artificial saliva (AS; control). The color change (DE) was evaluated before (baseline) and after thermocycling (T1), and after immersion in solution for 1 h (T2), 3 h (T3), 24 h (T4), 48 h (T5), and 96 h (T6). The CIE Lab system was used to determine the color changes. The thermocycling test was performed for 5000 cycles. Data were submitted to three-way repeated-measures analysis of variance and Tukey's test (p<0.05). When the samples were immersed in each mouthwash, all assessed factors, associated or not, significantly influenced the color change values, except there was no association between the mouthwash and acrylic resin. Similarly, when the samples were immersed in each beverage, all studied factors influenced the color change values. In general, regardless of the solution, LU exhibited the greatest DE values in the period from T1 to T5; and QC presented the greatest DE values at T6. Thus, thermocycling and immersion in the various solutions influenced the color stability of acrylic resins and QC showed the greatest color alteration.

Fabrication, Rheology and Antioxidant Activity of Palm Esters-based Emulsions Loaded with Tocotrienol

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S.H NG

2014-06-01

The yield stress of the emulsions increased with increasing acoustic amplitudes. The viscoelasticity of the emulsions were enhanced by the increase in the oil and surfactant concentrations. The emulsions with higher oil phase concentration [30% (w/w] showed greater elasticity which implied strong dynamic rigidity of the emulsions. The cohesive energy increased significantly with surfactant concentration especially for the emulsions with 30% (w/w oil phase concentration. The palm oil esters emulsions containing tocotrienol gave higher Trolox equivalent antioxidant capacity values which implied higher antioxidant capability. The tocotrienol in emulsion with 30% (w/w dispersed phase showed that they were the most stable with longest shelf life and exhibited greater inhibitory effects on the ABTS".

Characterization of flaxseed oil emulsions.

Science.gov (United States)

Lee, Pei-En; Choo, Wee-Sim

2015-07-01

The emulsifying capacity of surfactants (polysorbate 20, polysorbate 80 and soy lecithin) and proteins (soy protein isolate and whey protein isolate) in flaxseed oil was measured based on 1 % (w/w) of emulsifier. Surfactants showed significantly higher emulsifying capacity compared to the proteins (soy protein isolate and whey protein isolate) in flaxseed oil. The emulsion stability of the flaxseed oil emulsions with whey protein isolate (10 % w/w) prepared using a mixer was ranked in the following order: 1,000 rpm (58 min) ≈ 1,000 rpm (29 min) ≈ 2,000 rpm (35 min) >2,000 rpm (17.5 min). The emulsion stability of the flaxseed oil emulsions with whey protein isolate (10 % w/w) prepared using a homogenizer (Ultra Turrax) was independent of the speed and mixing time. The mean particle size of the flaxseed oil emulsions prepared using the two mixing devices ranged from 23.99 ± 1.34 μm to 47.22 ± 1.99 μm where else the particle size distribution and microstructure of the flaxseed oil emulsions demonstrated using microscopic imaging were quite similar. The flaxseed oil emulsions had a similar apparent viscosity and exhibited shear thinning (pseudoplastic) behavior. The flaxseed oil emulsions had L* value above 70 and was in the red-yellow color region (positive a* and b* values).

Emulsion-Based Intradermal Delivery of Melittin in Rats

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Sang Mi Han

2017-05-01

Full Text Available Bee venom (BV has long been used as a traditional medicine. The aim of the present study was to formulate a BV emulsion with good rheological properties for dermal application and investigate the effect of formulation on the permeation of melittin through dermatomed rat skin. A formulated emulsion containing 1% (w/v BV was prepared. The emulsion was compared with distilled water (DW and 25% (w/v N-methyl-2-pyrrolidone (NMP in DW. Permeation of melittin from aqueous solution through the dermatomed murine skin was evaluated using the Franz diffusion cells. Samples of receptor cells withdrawn at pre-determined time intervals were measured for melittin amount. After the permeation study, the same skin was used for melittin extraction. In addition, a known amount of melittin (5 μg/mL was added to stratum corneum, epidermis, and dermis of the rat skin, and the amount of melittin was measured at pre-determined time points. The measurement of melittin from all samples was done with HPLC-MS/MS. No melittin was detected in the receptor phase at all time points in emulsion, DW, or NMP groups. When the amount of melittin was further analyzed in stratum corneum, epidermis, and dermis from the permeation study, melittin was still not detected. In an additional experiment, the amount of melittin added to all skin matrices was corrected against the amount of melittin recovered. While the total amount of melittin was retained in the stratum corneum, less than 10% of melittin remained in epidermis and dermis within 15 and 30 min, respectively. Skin microporation with BV emulsion facilitates the penetration of melittin across the stratum corneum into epidermis and dermis, where emulsified melittin could have been metabolized by locally-occurring enzymes.

Emulsion-Based Intradermal Delivery of Melittin in Rats.

Science.gov (United States)

Han, Sang Mi; Kim, Se Gun; Pak, Sok Cheon

2017-05-19

Bee venom (BV) has long been used as a traditional medicine. The aim of the present study was to formulate a BV emulsion with good rheological properties for dermal application and investigate the effect of formulation on the permeation of melittin through dermatomed rat skin. A formulated emulsion containing 1% ( w / v ) BV was prepared. The emulsion was compared with distilled water (DW) and 25% ( w / v ) N -methyl-2-pyrrolidone (NMP) in DW. Permeation of melittin from aqueous solution through the dermatomed murine skin was evaluated using the Franz diffusion cells. Samples of receptor cells withdrawn at pre-determined time intervals were measured for melittin amount. After the permeation study, the same skin was used for melittin extraction. In addition, a known amount of melittin (5 μg/mL) was added to stratum corneum, epidermis, and dermis of the rat skin, and the amount of melittin was measured at pre-determined time points. The measurement of melittin from all samples was done with HPLC-MS/MS. No melittin was detected in the receptor phase at all time points in emulsion, DW, or NMP groups. When the amount of melittin was further analyzed in stratum corneum, epidermis, and dermis from the permeation study, melittin was still not detected. In an additional experiment, the amount of melittin added to all skin matrices was corrected against the amount of melittin recovered. While the total amount of melittin was retained in the stratum corneum, less than 10% of melittin remained in epidermis and dermis within 15 and 30 min, respectively. Skin microporation with BV emulsion facilitates the penetration of melittin across the stratum corneum into epidermis and dermis, where emulsified melittin could have been metabolized by locally-occurring enzymes.

Innovative Natural Ingredients-Based Multiple Emulsions: The Effect on Human Skin Moisture, Sebum Content, Pore Size and Pigmentation

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Ugne Cizauskaite

2018-06-01

Full Text Available The increased interest in natural cosmetics has resulted in a higher market demand for preservative-free products based on herbal ingredients. An innovative W/O/W type emulsions containing herbal extracts were prepared directly; its cation form was induced by an ethanolic rosemary extract and stabilized using weak herbal gels. Due to the wide phytochemical composition of herbal extracts and the presence of alcohol in the emulsion system, which can cause skin irritation, sensitization or dryness when applied topically, the safety of the investigated drug delivery system is necessary. The aim of our study was to estimate the potential of W/O/W emulsions based on natural ingredients for skin irritation and phototoxicity using reconstructed 3D epidermis models in vitro and to evaluate in vivo its effect on human skin moisture, sebum content and pigmentation by biomedical examination using a dermatoscopic camera and corneometer. According to the results obtained after in vitro cell viability test the investigated emulsion was neither irritant nor phototoxic to human skin keratinocytes. W/O/W emulsion did not cause skin dryness in vivo, despite the fact that it contained ethanol. We can conclude that the emulsion is safe for use as a leave-on product due to the positive effect on human skin characteristics or as a semisolid pharmaceutical base where active compounds could be encapsulated.

Synthesis of acrylic prepolymer

International Nuclear Information System (INIS)

Hussin bin Mohd Nor; Dahlan bin Haji Mohd; Mohamad Hilmi bin Mahmood.

1988-04-01

An acrylic prepolymer was synthesized from glycidyl methacrylate (GMA), butyl methacrylate (BMA), methyl methacrylate (MMA) and acrylic acid (AA). Butyl acetate (BAc), benzoyl peroxide (BzO), 4-methoxyphenol (MPh) and triethylamine (TEA) were used as solvent, initiator, inhibitor and catalyst respectively. Observations of the synthesis leading to the formation of acrylic prepolymer are described. (author)

Automatic readout system for superheated emulsion based neutron detector

International Nuclear Information System (INIS)

Meena, J.P.; Parihar, A.; Vaijapurkar, S.G.; Mohan, Anand

2011-01-01

The paper presents a microcontroller based automatic reader system for neutron measurement using indigenously developed superheated emulsion detector. The system is designed for real time counting of bubbles formed in superheated emulsion detector. A piezoelectric transducer is used for sensing bubble acoustic during the nucleation. The front end of system is mainly consisting of specially designed signal conditioning unit, piezoelectric transducer, an amplifier, a high-pass filter, a differentiator, a comparator and monostable multivibrator. The system is based on PlC 18F6520 microcontroller having large internal SRAM, 10-bit internal ADC, I 2 C interface, UART/USART modules. The paper also describes the design of following microcontroller peripheral units viz temperature monitoring, battery monitoring, LCD display, keypad and a serial communication. The reader system measures and displays neutron dose and dose rate, number of bubble and elapsed time. The developed system can be used for detecting very low neutron leakage in the accelerators, nuclear reactors and nuclear submarines. The important features of system are compact, light weight, cost effective and high neutron sensitivity. The prototype was tested and evaluated by exposing to 241 Am-Be neutron source and results have been reported. (author)

Dairy-Based Emulsions: Viscosity Affects Fat Difference Thresholds and Sweetness Perception

Directory of Open Access Journals (Sweden)

Susann Zahn

2013-11-01

Full Text Available In complex emulsions, viscosity or viscosity-associated sensory attributes such as creaminess are important for quality assessment and product differentiation. Two sets of emulsions with fat or locust bean gum content being varied at seven levels were developed; the two emulsions at each level had similar apparent viscosity. Additionally, sugar concentration was kept constant either with respect to total emulsion, or with respect to the aqueous phase. Series of two-alternative forced choice tests were performed with one constant stimulus, and just noticeable differences were calculated using probability regression. The results show that, when viscosity was not compensated, it was easy for the subjects to (a distinguish emulsions with different fat content when the fat content was addressed in the question, and to (b distinguish emulsions with different fat or locust bean gum content when creaminess was addressed. For the latter descriptor, it is of minor importance whether viscosity is altered by fat content or a thickener. Weber fractions that were calculated for viscosity were approximately 0.20. The quantitative effects of viscosity on sweetness, however, depend on how product rheology was modified.

Steroidal Compounds in Commercial Parenteral Lipid Emulsions

Science.gov (United States)

Xu, Zhidong; Harvey, Kevin A.; Pavlina, Thomas; Dutot, Guy; Hise, Mary; Zaloga, Gary P.; Siddiqui, Rafat A.

2012-01-01

Parenteral nutrition lipid emulsions made from various plant oils contain steroidal compounds, called phytosterols. During parenteral administration of lipid emulsions, phytosterols can reach levels in the blood that are many fold higher than during enteral administration. The elevated phytosterol levels have been associated with the development of liver dysfunction and the rare development of liver failure. There is limited information available in the literature related to phytosterol concentrations in lipid emulsions. The objective of the current study was to validate an assay for steroidal compounds found in lipid emulsions and to compare their concentrations in the most commonly used parenteral nutrition lipid emulsions: Liposyn® II, Liposyn® III, Lipofundin® MCT, Lipofundin® N, Structolipid®, Intralipid®, Ivelip® and ClinOleic®. Our data demonstrates that concentrations of the various steroidal compounds varied greatly between the eight lipid emulsions, with the olive oil-based lipid emulsion containing the lowest levels of phytosterols and cholesterol, and the highest concentration of squalene. The clinical impression of greater incidences of liver dysfunction with soybean versus MCT/LCT and olive/soy lipid emulsions may be reflective of the levels of phytosterols in these emulsions. This information may help guide future studies and clinical care of patients with lipid emulsion-associated liver dysfunction. PMID:23016123

Steroidal compounds in commercial parenteral lipid emulsions.

Science.gov (United States)

Xu, Zhidong; Harvey, Kevin A; Pavlina, Thomas; Dutot, Guy; Hise, Mary; Zaloga, Gary P; Siddiqui, Rafat A

2012-08-01

Parenteral nutrition lipid emulsions made from various plant oils contain steroidal compounds, called phytosterols. During parenteral administration of lipid emulsions, phytosterols can reach levels in the blood that are many fold higher than during enteral administration. The elevated phytosterol levels have been associated with the development of liver dysfunction and the rare development of liver failure. There is limited information available in the literature related to phytosterol concentrations in lipid emulsions. The objective of the current study was to validate an assay for steroidal compounds found in lipid emulsions and to compare their concentrations in the most commonly used parenteral nutrition lipid emulsions: Liposyn(®) II, Liposyn(®) III, Lipofundin(®) MCT, Lipofundin(®) N, Structolipid(®), Intralipid(®), Ivelip(®) and ClinOleic(®). Our data demonstrates that concentrations of the various steroidal compounds varied greatly between the eight lipid emulsions, with the olive oil-based lipid emulsion containing the lowest levels of phytosterols and cholesterol, and the highest concentration of squalene. The clinical impression of greater incidences of liver dysfunction with soybean versus MCT/LCT and olive/soy lipid emulsions may be reflective of the levels of phytosterols in these emulsions. This information may help guide future studies and clinical care of patients with lipid emulsion-associated liver dysfunction.

Matrix normalized MALDI-TOF quantification of a fluorotelomer-based acrylate polymer.

Science.gov (United States)

Rankin, Keegan; Mabury, Scott A

2015-05-19

The degradation of fluorotelomer-based acrylate polymers (FTACPs) has been hypothesized to serve as a source of the environmental contaminants, perfluoroalkyl carboxylates (PFCAs). Studies have relied on indirect measurement of presumed degradation products to evaluate the environmental fate of FTACPs; however, this approach leaves a degree of uncertainty. The present study describes the development of a quantitative matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry method as the first direct analysis method for FTACPs. The model FTACP used in this study was poly(8:2 FTAC-co-HDA), a copolymer of 8:2 fluorotelomer acrylate (8:2 FTAC) and hexadecyl acrylate (HDA). Instead of relying on an internal standard polymer, the intensities of 40 poly(8:2 FTAC-co-HDA) signals (911-4612 Da) were normalized to the signal intensity of a matrix-sodium cluster (659 Da). We termed this value the normalized polymer response (P(N)). By using the same dithranol solution for the sample preparation of poly(8:2 FTAC-co-HDA) standards, calibration curves with coefficient of determinations (R(2)) typically >0.98 were produced. When poly(8:2 FTAC-co-HDA) samples were prepared with the same dithranol solution as the poly(8:2 FTAC-co-HDA) standards, quantification to within 25% of the theoretical concentration was achieved. This approach minimized the sample-to-sample variability that typically plagues MALDI-TOF, and is the first method developed to directly quantify FTACPs.

A Comparative Study of the Physicochemical Properties of a Virgin Coconut Oil Emulsion and Commercial Food Supplement Emulsions

Directory of Open Access Journals (Sweden)

Yih Phing Khor

2014-07-01

Full Text Available Food manufacturers are interested in developing emulsion-based products into nutritional foods by using beneficial oils, such as fish oil and virgin coconut oil (VCO. In this study, the physicochemical properties of a VCO oil-in-water emulsion was investigated and compared to other commercial oil-in-water emulsion products (C1, C2, C3, and C4. C3 exhibited the smallest droplet size of 3.25 µm. The pH for the emulsion samples ranged from 2.52 to 4.38 and thus were categorised as acidic. In a texture analysis, C2 was described as the most firm, very adhesive and cohesive, as well as having high compressibility properties. From a rheological viewpoint, all the emulsion samples exhibited non-Newtonian behaviour, which manifested as a shear-thinning property. The G'G'' crossover illustrated by the VCO emulsion in the amplitude sweep graph but not the other commercial samples illustrated that the VCO emulsion had a better mouthfeel. In this context, the VCO emulsion yielded the highest zeta potential (64.86 mV, which was attributed to its strong repulsive forces, leading to a good dispersion system. C2 comprised the highest percentage of fat among all emulsion samples, followed by the VCO emulsion, with 18.44% and 6.59%, respectively.

Does lactobionic acid affect the colloidal structure and skin moisturizing potential of the alkyl polyglucoside-based emulsion systems?

Science.gov (United States)

Tasic-Kostov, M Z; Reichl, S; Lukic, M Z; Jaksic, I N; Savic, S D

2011-11-01

Moisturizing creams are the most prescribed products in dermatology, essential in maintaining healthy skin as well as in the topical treatment of some diseases. The irritation potential of commonly used emulsifiers and moisturizing ingredients, but also their mutual interactions, could affect the functionality and safety of those dermopharmaceutics. The aim of this study was to promote moisturizing alkyl polyglucoside (APG)-based emulsion as vehicle for lactobionic acid (LA), advantageous representative of the alphahydroxyacids (AHAs)-multifunctional moisturizers, assessing the safety for use (in vitro acute skin irritation test using cytotoxicity assay compared with in vivo data obtained using skin bioengineering methods) and in vivo moisturizing capacity (bioengineering of the skin). In order to investigate possible interactions between APG mild natural emulsifier-based emulsion and LA, a deeper insight into the colloidal structure of the placebo and the emulsion with LA was given using polarization and transmission electron microscopy, rheology, thermal and texture analysis. This study showed that APG-based emulsions could be promoted as safe cosmetic/dermopharmaceutical vehicles and carriers for extremely acidic and hygroscopic AHA class of actives (specifically LA); prospective safety for human use of both APG and LA with the correlation between in vivo and in vitro findings was shown. However, it was revealed that LA strongly influenced the colloidal structure of the emulsion based on APGs and promoted the formation of lamellar structures which reflects onto the mode of water distribution within the cream. The advantageous skin hydrating potential of LA-containing emulsion vs. placebo was unlikely to be achieved, pointing that emulsions stabilized by lamellar liquid crystalline structures probably are not satisfying carriers for highly hygroscopic actives in order to reach the full moisturizing potential. Safe and effective use on dry skin is presumed.

Kinetics of Waterborne Alkyd/Acrylic Hybrid Resin Free Radical Polymerization by Two Systems of Redox and Thermal Initiators

Directory of Open Access Journals (Sweden)

shirin Madadi

2012-12-01

Full Text Available Kinetics of radical polymerizations of waterborne alkyd/acrylic hybrid resin via batch mini-emulsion technique was studied using redox initiators (TBHP/Fe2+/EDTA/AsAc  and  TBHP/Fe2+/EDTA/SFS at relatively low temperatures and thermal initiators (BPO, KPS and AIBN at higher temperatures to seek the most suitable initiator system. At the end of all reactions the unreacted monomer content was reduced using post-polymerization technique; consequently, leading to increased monomer conversion and flm formation with improved properties. The kinetics of mini-emulsion polymerization showed that in all redox initiator systems (Fe2+ catalyst + EDTA chelating agent, the radials are produced at relatively low temperature with more effcient control of the reactor temperature. It was found that at 45°C TBHP/Fe2+/EDTA/SFS redox initiator system leads to 98% monomer conversion, a much higher rate than that of systems involved thermal initiators.

Influence of non-migratory metal-chelating active packaging film on food quality: impact on physical and chemical stability of emulsions.

Science.gov (United States)

Tian, Fang; Decker, Eric A; McClements, D Julian; Goddard, Julie M

2014-05-15

Previously, we developed a novel metal-chelating packaging film (PP-g-PAA) by grafting acrylic acid (AA) monomer from polypropylene (PP) film surface, and demonstrated its potential in controlling iron-promoted lipid oxidation. Herein, we further established the industrial practicality of this active film. Specifically, the influence of film surface area-to-product volume ratio (SA/V) and product pH on the application of the film was investigated using an oil-in-water emulsion system. The films equally inhibited lipid oxidation throughout the range of SA/V ratios tested (2-8 cm(2)/ml). PP-g-PAA films were most effective at pH 7.0, and the activity decreased with decreasing pH. The particle size examination of emulsions indicated no adverse influence from the active film on the stability of this emulsion system. FTIR analysis suggested a non-migratory nature of PP-g-PAA films. These results provide fundamental knowledge that will facilitate the application of this effective and economical active packaging film in the food industry. Copyright © 2013 Elsevier Ltd. All rights reserved.

Recent Emulsion Technologies

International Nuclear Information System (INIS)

Ariga, A.

2011-01-01

Emulsion technologies are very much developed in the last decade and still developing in both the emulsion gel and the data taking. Emulsion detectors are suitable for the neutrino experiments because they can distinguish all 3 flavors of neutrino. The OPERA experiment, a recent pillar in the emulsion experiments aiming at the first observation of the neutrino oscillation in CNGS beam in appearance mode, is running, showing the good capability to separate 3 flavor neutrino interactions. In this poster, the recent developments and prospects of the emulsions for the next generation experiments are reported.

Long-Chain Diacrylate Crosslinkers and Use of PEG Crosslinks in Poly(potassium acrylate-acrylic acid)/Kaolin Composite Superabsorbents

OpenAIRE

Koroush Kabiri; Siavash Nafisi; Mohammad jalaledin Zohuriaan-Mehr; Ali Akbar Yousefi

2013-01-01

Long-chain diacrylate crosslinkers based on linear α,ω-diols were synthesized and characterized using FTIR and 1H NMR spectroscopy. The highest reaction yield (99.5%) was due to polyethylene glycol diacrylate 1000 (PEGDA-1000). Then, kaolin-containing poly(potassium acrylate-acrylic acid) superabsorbent composites and kaolin-free counterparts were synthesized using PEGDA-1000.The effect of the crosslinker concentration on swelling, rheological and thermo-mechanical properties was investigated...

Tunable volatile release from organogel-emulsions based on the self-assembly of β-sitosterol and γ-oryzanol.

Science.gov (United States)

Chen, Xiao-Wei; Chen, Ya-Jun; Wang, Jin-Mei; Guo, Jian; Yin, Shou-Wei; Yang, Xiao-Quan

2017-04-15

A current challenge in the area of food emulsion is the design of microstructure that provides controlled release of volatile compounds during storage and consumption. Here, a new strategy addressed this problem at the fundamental level by describing the design of organogel-based emulsion from the self-assembly of β-sitosterol and γ-oryzanol that are capable of tuning volatile release. The results showed that the release rate (v 0 ), maximum headspace concentrations (C max ) and partition coefficients (k a / e ) above structured emulsions were significantly lower than unstructured emulsions and controlled release doing undergo tunable though the self-assembled interface and core fine microstructure from internal phase under dynamic and static condition. This result provides an understanding of how emulsions can behave as delivery system to better design novel food products with enhanced sensorial and nutritional attributes. Copyright © 2016 Elsevier Ltd. All rights reserved.

A field application of nanoparticle-based invert emulsion drilling fluids

Energy Technology Data Exchange (ETDEWEB)

Borisov, Alexey S.; Husein, Maen, E-mail: mhusein@ucalgary.ca [University of Calgary, Department of Chemical & Petroleum Engineering (Canada); Hareland, Geir [Oklahoma State University, Department of Chemical Engineering (United States)

2015-08-15

Application of nanotechnology in drilling fluids for the oil and gas industry has been a focus of several recent studies. A process for the in situ synthesis of nanoparticles (NPs) into drilling fluids has been developed previously in our group and showed that calcium-based NPs (CNPs) and iron-based NPs (INPs), respectively, with concentrations of 0.5–2.0 wt% can dramatically improve filtration properties of commercial drilling fluids in a laboratory environment. In this work, a modified process for the emulsion-based synthesis of NPs on a 20 m{sup 3} volume and its subsequent full-scale field testing are presented. Comparison between NP carrier fluids prepared under controlled environment in the laboratory and those prepared on a large scale in a mixing facility revealed very little variation in the main characteristics of the drilling fluid; including the size of the solid constituents. Transmission electron microscopy photographs suggest an average CNP particle size in the carrier fluid of 51 ± 11 nm. Results from the full-scale field test showed that total mud losses while drilling with CNP-based invert emulsion were on average 27 % lower than in the case of conventional fluids. This loss prevention falls within the range observed in the laboratory.

Steroidal Compounds in Commercial Parenteral Lipid Emulsions

Directory of Open Access Journals (Sweden)

Rafat A. Siddiqui

2012-08-01

Full Text Available Parenteral nutrition lipid emulsions made from various plant oils contain steroidal compounds, called phytosterols. During parenteral administration of lipid emulsions, phytosterols can reach levels in the blood that are many fold higher than during enteral administration. The elevated phytosterol levels have been associated with the development of liver dysfunction and the rare development of liver failure. There is limited information available in the literature related to phytosterol concentrations in lipid emulsions. The objective of the current study was to validate an assay for steroidal compounds found in lipid emulsions and to compare their concentrations in the most commonly used parenteral nutrition lipid emulsions: Liposyn^® II, Liposyn^® III, Lipofundin^® MCT, Lipofundin^® N, Structolipid^®, Intralipid^®, Ivelip^® and ClinOleic^®. Our data demonstrates that concentrations of the various steroidal compounds varied greatly between the eight lipid emulsions, with the olive oil-based lipid emulsion containing the lowest levels of phytosterols and cholesterol, and the highest concentration of squalene. The clinical impression of greater incidences of liver dysfunction with soybean versus MCT/LCT and olive/soy lipid emulsions may be reflective of the levels of phytosterols in these emulsions. This information may help guide future studies and clinical care of patients with lipid emulsion-associated liver dysfunction.

Regulation of the Contribution of Integrin to Cell Attachment on Poly(2-Methoxyethyl Acrylate (PMEA Analogous Polymers for Attachment-Based Cell Enrichment.

Directory of Open Access Journals (Sweden)

Takashi Hoshiba

Full Text Available Cell enrichment is currently in high demand in medical engineering. We have reported that non-blood cells can attach to a blood-compatible poly(2-methoxyethyl acrylate (PMEA substrate through integrin-dependent and integrin-independent mechanisms because the PMEA substrate suppresses protein adsorption. Therefore, we assumed that PMEA analogous polymers can change the contribution of integrin to cell attachment through the regulation of protein adsorption. In the present study, we investigated protein adsorption, cell attachment profiles, and attachment mechanisms on PMEA analogous polymer substrates. Additionally, we demonstrated the possibility of attachment-based cell enrichment on PMEA analogous polymer substrates. HT-1080 and MDA-MB-231 cells started to attach to poly(butyl acrylate (PBA and poly(tetrahydrofurfuryl acrylate (PTHFA, on which proteins could adsorb well, within 1 h. HepG2 cells started to attach after 1 h. HT-1080, MDA-MB-231, and HepG2 cells started to attach within 30 min to PMEA, poly(2-(2-methoxyethoxy ethyl acrylate-co-butyl acrylate (30:70 mol%, PMe2A and poly(2-(2-methoxyethoxy ethoxy ethyl acrylate-co-butyl acrylate (30:70 mol%, PMe3A, which suppress protein adsorption. Moreover, the ratio of attached cells from a cell mixture can be changed on PMEA analogous polymers. These findings suggested that PMEA analogous polymers can be used for attachment-based cell enrichment.

Development and characterization of novel antimicrobial bilayer films based on Polylactic acid (PLA)/Pickering emulsions.

Science.gov (United States)

Zhu, Jun-You; Tang, Chuan-He; Yin, Shou-Wei; Yang, Xiao-Quan

2018-02-01

Biodegradable food packaging is sustainable and has a great application prospect. PLA is a promising alternative for petroleum-derived polymers. However, PLA packaging suffers from poor barrier properties compared with petroleum-derived ones. To address this issue, we designed bilayer films based on PLA and Pickering emulsions. The formed bilayer films were compact and uniform and double layers were combined firmly. This strategy enhanced mechanical resistance, ductility and moisture barrier of Pickering emulsion films, and concomitantly enhanced the oxygen barrier for PLA films. Thymol loadings in Pickering emulsion layer endowed them with antimicrobial and antioxidant activity. The release profile of thymol was well fitted with Fick's second law. The antimicrobial activity of the films depended on film types, and Pickering emulsion layer presented larger inhibition zone than PLA layer, hinting that the films possessed directional releasing role. This study opens a promising route to fabricate bilayer architecture creating synergism of each layer. Copyright © 2017 Elsevier Ltd. All rights reserved.

Organic Thin Films Deposited by Emulsion-Based, Resonant Infrared, Matrix-Assisted Pulsed Laser Evaporation: Fundamentals and Applications

Science.gov (United States)

Ge, Wangyao

Thin film deposition techniques are indispensable to the development of modern technologies as thin film based optical coatings, optoelectronic devices, sensors, and biological implants are the building blocks of many complicated technologies, and their performance heavily depends on the applied deposition technique. Particularly, the emergence of novel solution-processed materials, such as soft organic molecules, inorganic compounds and colloidal nanoparticles, facilitates the development of flexible and printed electronics that are inexpensive, light weight, green and smart, and these thin film devices represent future trends for new technologies. One appealing feature of solution-processed materials is that they can be deposited into thin films using solution-processed deposition techniques that are straightforward, inexpensive, high throughput and advantageous to industrialize thin film based devices. However, solution-processed techniques rely on wet deposition, which has limitations in certain applications, such as multi-layered film deposition of similar materials and blended film deposition of dissimilar materials. These limitations cannot be addressed by traditional, vacuum-based deposition techniques because these dry approaches are often too energetic and can degrade soft materials, such as polymers, such that the performance of resulting thin film based devices is compromised. The work presented in this dissertation explores a novel thin film deposition technique, namely emulsion-based, resonant infrared, matrix-assisted pulsed laser evaporation (RIR-MAPLE), which combines characteristics of wet and dry deposition techniques for solution-processed materials. Previous studies have demonstrated the feasibility of emulsion-based RIR-MAPLE to deposit uniform and continuous organic, nanoparticle and blended films, as well as hetero-structures that otherwise are difficult to achieve. However, fundamental understanding of the growth mechanisms that govern

Rheology and microstructure of gluten and soya-based o/w emulsions

Energy Technology Data Exchange (ETDEWEB)

Bengoechea, Carlos; Cordobes, Felipe; Guerrero, Antonio [Universidad de Sevilla, Departamento de Ingenieria Quimica, Sevilla (Spain)

2006-10-15

Highly concentrated oil-in-water (o/w) emulsion stabilised by means of gluten and soya protein isolate (SPI) at low pH have been characterized by means of linear dynamic viscoelasticity and droplet size distribution analysis (DSD). The microstructure of these emulsions has been characterized at a colloidal level by using confocal laser scanning microscopy (CLSM) and light microscopy (LM). These emulsions always exhibited a behaviour characteristic of highly flocculated emulsions with a mechanical spectrum showing a well-developed plateau region. DSD results generally showed log normal bimodal profiles. Microstructure images revealed occurrence of a close packing of droplets with a broad distribution of sizes participating in the formation of a three dimensional flocculated network. The Mason model of elasticity of compressed emulsions has been used to correlate viscoelastic and microstructural parameters giving adequate fitting but underestimating the elastic properties obtained for the highest concentration of gluten. These deviations may be explained in terms of an enhancement of the elastic network formed in the aqueous phase in which the glutenin fraction must play an important role. (orig.)

Demulsification based on the thermal treatment (cooling and heating of W/O emulsions

Directory of Open Access Journals (Sweden)

Rajaković Vladana N.

2004-01-01

Full Text Available An important step in waste water treatment is the removal of oil from an O/W emulsion and the separation of oil and water into two phases, a process usually called demulsification. Modern methods of oil removal from waste water were described in the present study. Typical demulsification techniques include thermal, electrical, chemical, acoustic, or mechanical methods of emulsion treatment. The freeze/thaw process was found to be very effective for demulsification. In the freeze/thaw process, water removal from the W/O emulsion depends on the initial oil content, freezing temperature, freezing time, thawing rate and temperature. The described method is a non-destructive and physical method of emulsion treatment and because there is no addition of chemical agents there is no problem of further waste water treatment, which usually exists when chemicals are applied for demulsification. Different methods for oil content determination in the O/W emulsion were also applied and compared in this study (gravimetric, volumetric, measurement of oxygen consumption and emulsion pH, IR analysis of the emulsion, electro analytical measurement.

Synthetic Polymers at Interfaces: Monodisperse Emulsions Multiple Emulsions and Liquid Marbles

Science.gov (United States)

Sun, Guanqing

The adsorption of polymeric materials at interfaces is an energetically favorable process which is investigated in much diversified fields, such as emulsions, bubbles, foams, liquid marbles. Pickering emulsion, which is emulsion stabilized by solid particles has been investigated for over one century and preparation of Pickering emulsion with narrow size distribution is crucial for both the theoretical study of the stabilization mechanism and practical application, such as templated fabrication of colloidosomes. The precise control over the size and functionality of polymer latices allows the preparation of monodisperse Pickering emulsions with desired sizes through SPG membrane emulsification at rather rapid rate compared to microfludic production. Double or multiple emulsions have long been investigated but its rapid destabilization has always been a major obstacle in applying them into practical applications. The modern living polymerization techniques allow us to prepare polymers with designed structure of block copolymers which makes it possible to prepare ultra-stable multiple emulsions. The precise tuning of the ratio of hydrophobic part over the hydrophilic can unveil the stabilization mechanism. Liquid marble is a new type of materials of which liquid droplets are coated by dry particles. The coating of an outer layer of dry particles renders the liquid droplets non-sticky at solid surface which is useful in transportation of small amount of liquid without leakage at extreme low friction force. The property of liquid marbles relies largely on the stabilizers and the drying condition of polymeric latices is shown to have great influence on the property of liquid marbles. Firstly, an introduction to the interfacial and colloidal science with special attention to topics on emulsions, multiple emulsion and liquid marbles is given in Chapter 1. The unique features of an interface and a discussion on the definition of colloids are introduced prior to the

Control of particle size by feed composition in the nanolatexes produced via monomer-starved semicontinuous emulsion copolymerization.

Science.gov (United States)

Sajjadi, Shahriar

2015-05-01

Conventional batch and semicontinuous emulsion copolymerizations often produce large particles whose size cannot be easily correlated with the comonomer feed compositions, and are to some degree susceptible to composition drift. In contrast, we found that copolymer nanolatexes made via semicontinuous monomer-starved emulsion copolymerizations are featured with an average nanoparticle size being controlled by the feed composition, a high conversion achieved, and a high degree of particle composition uniformity. This was achieved because the rate of particle growth, during nucleation, was controlled by the rate of comonomer addition, and the copolymer composition, surfactant parking area on the particles, and nucleation efficiency determined by the comonomer feed composition. Two model systems, methyl methacrylate/styrene and vinyl acetate/butyl acrylate, with significant differences in water solubility were studied. Monomers were added to the aqueous solution of sodium dodecylsulfate and potassium persulfate at a low rate to achieve high instantaneous conversions. Copyright © 2015 Elsevier Inc. All rights reserved.

Effect of microwave cured acrylic resin on candidal growth in complete denture

International Nuclear Information System (INIS)

Rasmy, A.H.M.

2009-01-01

This study was conducted to evaluate the effect of heat-cured acrylic resin denture base and microwave-cured acrylic resin denture base on candidal growth . Seven completely edentulous male patients with on history of denture wearing participated in this study. all the selected patients were re-habilitated by mucosa supported complete dentures .The dentures were constructed from conventional heat-cured acrylic resin denture base following monoplane concept of occlusion. Before dismissing the patients and one month after denture insertion, salivary samples were collected according to oral rinse technique. one month resting period was allowed so as candidal count can reach to normal, then dentures were re based using microwave-cured acrylic denture base, before denture insertion and one month after denture insertion, salivary sample were collected before and one month following the same oral rinse technique.

Preparation, characterization, and antibacterial activity studies of silver-loaded poly(styrene-co-acrylic acid) nanocomposites

Energy Technology Data Exchange (ETDEWEB)

Song, Cunfeng [Department of Materials Science and Engineering, College of Materials, Xiamen University, Xiamen 361005 (China); Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005 (China); Chang, Ying; Cheng, Ling; Xu, Yiting [Department of Materials Science and Engineering, College of Materials, Xiamen University, Xiamen 361005 (China); Chen, Xiaoling, E-mail: tinachen0628@163.com [Department of Endodontics, Xiamen Stomatology Hospital, Teaching Hospital of Fujian Medical University, Xiamen 361003 (China); Zhang, Long; Zhong, Lina [Department of Materials Science and Engineering, College of Materials, Xiamen University, Xiamen 361005 (China); Dai, Lizong, E-mail: lzdai@xmu.edu.cn [Department of Materials Science and Engineering, College of Materials, Xiamen University, Xiamen 361005 (China)

2014-03-01

A simple method for preparing a new type of stable antibacterial agent was presented. Monodisperse poly(styrene-co-acrylic acid) (PSA) nanospheres, serving as matrices, were synthesized via soap-free emulsion polymerization. Field-emission scanning electron microscopy micrographs indicated that PSA nanospheres have interesting surface microstructures and well-controlled particle size distributions. Silver-loaded poly(styrene-co-acrylic acid) (PSA/Ag-NPs) nanocomposites were prepared in situ through interfacial reduction of silver nitrate with sodium borohydride, and further characterized by transmission electron microscopy and X-ray diffraction. Their effects on antibacterial activity including inhibition zone, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and bactericidal kinetics were evaluated. In the tests, PSA/Ag-NPs nanocomposites showed excellent antibacterial activity against both gram-positive Staphylococcus aureus and gram-negative Escherichia coli. These nanocomposites are considered to have potential application in antibacterial coatings on biomedical devices to reduce nosocomial infection rates. - Highlights: • A new type of antibacterial agent (PSA/Ag-NPs nanocomposites) was synthesized. • The antibacterial activity against S. aureus and E. coli was studied. • Inhibition zone, MIC, MBC, and bactericidal kinetics were evaluated. • PSA/Ag-NPs nanocomposites showed excellent antibacterial activity.

Acrylic and metal based Y-branch plastic optical fiber splitter with optical NOA63 polymer waveguide taper region

Science.gov (United States)

Ehsan, Abang Annuar; Shaari, Sahbudin; Rahman, Mohd Kamil Abd.

2011-01-01

We proposed a simple low-cost acrylic and metal-based Y-branch plastic optical fiber (POF) splitter which utilizes a low cost optical polymer glue NOA63 as the main waveguiding medium at the waveguide taper region. The device is composed of three sections: an input POF waveguide, a middle waveguide taper region and output POF waveguides. A desktop high speed CNC engraver is utilized to produce the mold inserts used for the optical devices. Short POF fibers are inserted into the engraved slots at the input and output ports. UV curable optical polymer glue NOA63 is injected into the waveguide taper region and cured. The assembling is completed when the top plate is positioned to enclose the device structure and connecting screws are secured. Both POF splitters have an average insertion loss of 7.8 dB, coupling ratio of 55: 45 and 57: 43 for the acrylic and metal-based splitters respectively. The devices have excess loss of 4.82 and 4.73 dB for the acrylic and metal-based splitters respectively.

The sensitizing capacity of multifunctional acrylates in the guinea pig.

Science.gov (United States)

Björkner, B

1984-10-01

The multifunctional acrylates used in ultraviolet (UV) curable resins act as cross-linkers and "diluents". They are usually based on di(meth)acrylate esters of dialcohols or tri- and tetra-acrylate esters of polyalcohols. In UV-curable coatings, the most commonly used are pentaerythritol triacrylate (PETA), trimethylolpropane triacrylate (TMPTA) and 1,6-hexanediol diacrylate (HDDA). In other uses, such as dental composite resin materials, the dimethacrylic monomers based on n-ethylene glycol are the most useful. The sensitizing capacity of various multifunctional acrylates and their cross-reactivity pattern have been investigated with the guinea pig maximization test. The tests show that BUDA (1,4-butanediol diacrylate) and HDDA are moderate to strong sensitizers and that they probably cross-react with each other. The n-ethylene glycol diacrylates and methacrylates tested are weak or non-sensitizers. Tripropylene glycol diacrylate (TPGDA) is a moderate and neopentyl glycol diacrylate (NPGDA) a strong sensitizer, whereas neopentyl glycol dimethacrylate is a non-sensitizer. The commercial PETA is a mixture of pentaerythritol tri- and tetra-acrylate (PETA-3 and PETA-4). PETA-3 is a much stronger sensitizer than PETA-4. Simultaneous reactions were seen between PETA-3, PETA-4 and TMPTA. The oligotriacrylate OTA 480 is a moderate sensitizer, but no concomitant reactions were seen with PETA-3, PETA-4 or TMPTA. Of the multifunctional acrylates tested, the di- and triacrylic compounds should be regarded as potent sensitizers. The methacrylated multifunctional acrylic compounds are weak or non-sensitizers.

Acrylic vessel cleaning tests

International Nuclear Information System (INIS)

Earle, D.; Hahn, R.L.; Boger, J.; Bonvin, E.

1997-01-01

The acrylic vessel as constructed is dirty. The dirt includes blue tape, Al tape, grease pencil, gemak, the glue or residue form these tapes, finger prints and dust of an unknown composition but probably mostly acrylic dust. This dirt has to be removed and once removed, the vessel has to be kept clean or at least to be easily cleanable at some future stage when access becomes much more difficult. The authors report on the results of a series of tests designed: (a) to prepare typical dirty samples of acrylic; (b) to remove dirt stuck to the acrylic surface; and (c) to measure the optical quality and Th concentration after cleaning. Specifications of the vessel call for very low levels of Th which could come from tape residues, the grease pencil, or other sources of dirt. This report does not address the concerns of how to keep the vessel clean after an initial cleaning and during the removal of the scaffolding. Alconox is recommended as the cleaner of choice. This acrylic vessel will be used in the Sudbury Neutrino Observatory

Immunomodulatory and Physical Effects of Oil Composition in Vaccine Adjuvant Emulsions

Science.gov (United States)

Fox, Christopher B.; Baldwin, Susan L.; Duthie, Malcolm S.; Reed, Steven G.; Vedvick, Thomas S.

2011-01-01

Squalene-based oil-in-water emulsions have been used for years in some seasonal and pandemic influenza vaccines. However, concerns have been expressed regarding squalene source and potential biological activities. Little information is available regarding the immunomodulatory activity of squalene in comparison with other metabolizable oils in the context of oil-in-water emulsions formulated with vaccines. The present work describes the manufacture and physical characterization of emulsions composed of different classes of oils, including squalene, long chain triglycerides, a medium chain triglyceride, and a perfluorocarbon, all emulsified with egg phosphatidylcholine. Some differences were apparent among the non-squalene oils in terms of emulsion stability, including higher size polydispersity in the perfluorocarbon emulsion, more rapid visual instability at 60 °C for the long-chain triglyceride and perfluorocarbon emulsions, and an increased creaming rate in the medium-chain triglyceride emulsion at 60 °C as detected by laser scattering optical profiling. The biological activity of each of these emulsions was compared when formulated with either a recombinant malaria antigen or a split-virus inactivated influenza vaccine. Overall, vaccines containing the squalene emulsion elicited higher antibody titers and more abundant long-lived plasma cells than vaccines containing emulsions based on other oils. Since squalene-based emulsions show higher adjuvant potency compared to the other oils tested, non-squalene oils may be more suitable as carriers of amphiphilic or hydrophobic immunostimulatory molecules (such as TLR agonists) rather than as stand-alone adjuvants. PMID:21906648

Stabilization Improves Theranostic Properties of Lipiodol{sup ®}-Based Emulsion During Liver Trans-arterial Chemo-embolization in a VX2 Rabbit Model

Energy Technology Data Exchange (ETDEWEB)

Deschamps, F., E-mail: frederic.deschamps@gustaveroussy.fr; Farouil, G. [Université Paris-Saclay, Département de radiologie Interventionnelle, Gustave Roussy (France); Gonzalez, W.; Robic, C. [Guerbet France, Guerbet (France); Paci, A.; Mir, L. M. [Université Paris-Saclay, UMR 8203 (France); Tselikas, L.; Baère, T. de [Université Paris-Saclay, Département de radiologie Interventionnelle, Gustave Roussy (France)

2017-06-15

PurposeTo demonstrate that stability is a crucial parameter for theranostic properties of Lipiodol{sup ®}-based emulsions during liver trans-arterial chemo-embolization.Materials and MethodsWe compared the theranostic properties of two emulsions made of Lipiodol{sup ®} and doxorubicin in two successive animal experiments (One VX2 tumour implanted in the left liver lobe of 30 rabbits). Emulsion-1 reproduced one of the most common way of preparation (ratio of oil/water: 1/1), and emulsion-2 was designed to obtain a water-in-oil emulsion with enhanced stability (ratio of oil/water: 3/1, plus an emulsifier). The first animal experiment compared the tumour selectivity of the two emulsions: seven rabbits received left hepatic arterial infusion (HAI) of emulsion-1 and eight received HAI of emulsion-2. 3D-CBCT acquisitions were acquired after HAI of every 0.1 mL to measure the densities’ ratios between the tumours and the left liver lobes. The second animal experiment compared the plasmatic and tumour doxorubicin concentrations after HAI of 1.5 mg of doxorubicin administered either alone (n = 3) or in emulsion-1 (n = 6) or in emulsion-2 (n = 6).ResultsEmulsion-2 resulted in densities’ ratios between the tumours and the left liver lobes that were significantly higher compared to emulsion-1 (up to 0.4 mL infused). Plasmatic doxorubicin concentrations (at 5 min) were significantly lower after HAI of emulsion-2 (19.0 μg/L) than emulsion-1 (275.3 μg/L, p < 0.01) and doxorubicin alone (412.0 μg/L, p < 0.001), and tumour doxorubicin concentration (day-1) was significantly higher after HAI of emulsion-2 (20,957 ng/g) than in emulsion-1 (8093 ng/g, p < 0.05) and doxorubicin alone (2221 ng/g, p < 0.01).ConclusionStabilization of doxorubicin in a water-in-oil Lipiodol{sup ®}-based emulsion results in better theranostic properties.

Use of olive oil-in-water gelled emulsions in model turkey breast emulsions

Science.gov (United States)

Serdaroğlu, M.; Öztürk, B.

2017-09-01

Today, gelled emulsion systems offer a novel possibility in lipid modification of meat products. In this study, we aimed to investigate the quality characteristics of model turkey emulsions that were prepared with olive oil-in-water gelled emulsion (GE) as partial or total beef fat replacer. The results indicated that while most of the GE treatments showed equivalent emulsion characteristics in terms of emulsion stability, water-holding capacity and cook yield, utilization of 100% GE as the lipid source could increase total expressible fluid of the model turkey emulsion and thus negatively affect the quality. Utilization of GE was effective in total fat reduction, as the model turkey emulsions formulated with more than 50% GE had significantly lower fat content compared to full-beef fat control model emulsion. However, beef fat replacement with GE produced considerable changes in colour parameters. Finally, it was concluded that utilization of GE as a partial beef fat replacer has good potential to enhance stability and reduce total fat in turkey meat emulsion products.

Fracture toughness of heat cured denture base acrylic resin modified with Chlorhexidine and Fluconazole as bioactive compounds.

Science.gov (United States)

Al-Haddad, Alaa; Vahid Roudsari, Reza; Satterthwaite, Julian D

2014-02-01

This study investigated the impact of incorporating Chlorhexidine and Fluconazole as bioactive compounds on the fracture toughness of conventional heat cured denture base acrylic resin material (PMMA). 30 single edge-notched (SEN) samples were prepared and divided into three groups. 10% (mass) Chlorhexidine and 10% (mass) Diflucan powder (4.5% mass Fluconazole) were added to heat cured PMMA respectively to create the two study groups. A third group of conventional heat cured PMMA was prepared as the control group. Fracture toughness (3-point bending test) was carried out for each sample and critical force (Fc) and critical stress intensity factor (KIC) values measured. Data were subject to parametric statistical analysis using one-way ANOVA and Post hoc Bonferroni test (p=0.05). Fluconazole had no significant effect on the fracture toughness of the PMMA while Chlorhexidine significantly reduced the KIC and therefore affected the fracture toughness. When considering addition of a bioactive material to PMMA acrylic, Chlorhexidine will result in reduced fracture toughness of the acrylic base while Fluconazole has no effect. Copyright © 2013 Elsevier Ltd. All rights reserved.

Protective effect of conditioning agents on Afro-ethnic hair chemically treated with thioglycolate-based straightening emulsion.

Science.gov (United States)

Dias, Tania Cristina de Sá; Baby, André Rolim; Kaneko, Telma Mary; Velasco, Maria Valéria Robles

2008-06-01

Straightening is a chemical process by which excessively curly hair is straightened in an irreversible way. Generally, products are formulated as emulsions with high pH value (9.0-12.0), which, after applied on hair, cause considerable damage, making it dry and fragile. This research work evaluated the protective effect of lauryl PEG/PPG-18/18 methicone, cyclopentasiloxane (and) PEG-12 dimethicone cross-polymer, jojoba oil, and aqua (and) cystine bis-PG propyl silanetriol, as conditioning agents, on Afro-ethnic hair locks treated with thioglycolate-based straightening emulsions by protein loss, combability, and traction to rupture. Standard Afro-ethnic hair locks were prepared following a protocol for straightening emulsion application. Considering the assays performed, the addition of conditioning agents to the straightening emulsion with ammonium thioglycolate benefited the hair fiber, thus diminishing protein loss, protecting the hair thread, and improving resistance to breakage. Jojoba oil and lauryl PEG/PPG-18/18 methicone were the conditioning agents that presented the best results. Straightening emulsions with ammonium thioglycolate containing aqua (and) cystine bis-PG propyl silanetriol and cyclopentasiloxane (and) PEG-12 dimethicone cross-polymer were the ones that provided higher breakage resistance of the thread.

Structured triglyceride emulsions in parenteral nutrition.

Science.gov (United States)

Chambrier, C; Lauverjat, M; Bouletreau, P

2006-08-01

Over the past 3 decades, various concepts for IV fat emulsions (IVFE) have been developed. A randomized, structured-lipid emulsion based on an old technology has recently become available. This structured-lipid emulsion is produced by mixing medium-chain triglycerides and long-chain triglycerides, then allowing hydrolysis to form free fatty acids, followed by random transesterification of the fatty acids into mixed triglyceride molecules. Studies in animals have shown an improvement in nitrogen balance with the use of these lipid emulsions. Only 8 human clinical studies with these products have been performed. The results of these human clinical studies have been less promising than the animal studies; however, an improvement in nitrogen balance and lipid metabolism exceeds results associated with infusion of long-chain triglycerides (LCT) or a physical mixture of long-chain triglycerides and medium-chain triglycerides (LCT-MCT). Structured-lipid emulsion seems to induce less elevation in serum liver function values compared with standard IVFEs. In addition, structured-lipid emulsions have no detrimental effect on the reticuloendothelial system. Further studies are necessary in order to recommend the use of structured-lipid emulsions. The clinical community hopes that chemically defined structured triglycerides will make it possible to determine the distribution of specific fatty acids on a specific position on the glycerol core and therefore obtain specific activity for a specific clinical situation.

Decarboxylation-based traceless linking with aroyl acrylic acids

DEFF Research Database (Denmark)

Nielsen, John

1998-01-01

beta-Keto carboxylic acids are known to decarboxylate readily. In our pursuit to synthesize beta-indolinyl propiophenones, we have exploited this chemistry as a mean of establishing a traceless handle. 2-Aroyl acrylic acids have been esterified to a trityl resin, after which Michael-type addition...

α-Tocopherol/chitosan-based nanoparticles: characterization and preliminary investigations for emulsion systems application

Science.gov (United States)

Aresta, Antonella; Calvano, Cosima Damiana; Trapani, Adriana; Zambonin, Carlo Giorgio; De Giglio, Elvira

2014-02-01

The processes of lipids oxidation represent a great concern for the consumer health because they are one of the major causes of quality deterioration in fat-containing products. One of the most effective methods of delaying lipid oxidation consists in incorporating antioxidants. The present investigation describes the formulation of chitosan and novel glycol chitosan nanoparticles (NPs) loaded with α-Tocopherol (αToc-NPs). The obtained NPs were characterized by various techniques, such as particle size (showing mean diameters in the range 335-503 nm) and zeta potential measurements, X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy. The NPs were, then, added in the preparation of oil-in-water simple emulsion both to make the lipophilic αToc available in an aqueous medium and to prevent emulsion oxidation. For this purpose, a new highly sensitive, simple and solvent-free method based on a solid phase microextraction (SPME) coupled to gas chromatography mass spectrometry was developed for the determination of αToc in aqueous medium. All the parameters influencing SPME, including fiber coating, time and temperature extraction, pH, ionic strength and desorption conditions, have been carefully screened. The method was successfully applied to the determination of vitamin in the αToc-NPs and its release from NPs-enriched simple emulsion formulations. SPME provided high recovery yields and the limits of detection and of quantification in emulsion were 0.1 and 0.5 μg/mg, respectively. The precision of the method has been also estimated. The delay of the lipid oxidation by the proposed formulations has been evaluated exploiting the Kreis test on αToc-NPs-enriched emulsions.

Emulsion-based encapsulation and delivery of nanoparticles for the controlled release of alkalinity within the subsurface environment

Science.gov (United States)

Ramsburg, C. A.; Muller, K.; Gill, J.

2012-12-01

Many current approaches to managing groundwater contamination rely on further advances in amendment delivery in order to initiate and sustain contaminant degradation or immobilization. In fact, limited or ineffective delivery is often cited when treatment objectives are not attained. Emulsions, specifically oil-in-water emulsions, have demonstrated potential to aid delivery of remediation amendments. Emulsions also afford opportunities to control the release of active ingredients encapsulated within the droplets. Our research is currently focused on the controlled release of nanoparticle-based buffering agents using oil-in-water emulsions. This interest is motivated by the fact that chemical and biological processes employed for the remediation and stewardship of contaminated sites often necessitate control of pH during treatment and, in some cases, long thereafter. Alkalinity-release nanoparticles (e.g., CaCO3, MgO) were suspended within soybean oil and subsequently encapsulated by through the creation of oil-in-water emulsions. These oil-in-water emulsions are designed to have physical properties which are favorable for subsurface delivery (nominal properties: 1 g/mL density; 10 cP viscosity; and 1.5 μm droplet diameter). Buffer capacity titrations suggest that MgO particles are moderately more accessible within the oil phase and nearly twice as effective (on a per mass basis) at releasing alkalinity (as compared to the CaCO3 particles). Results from experiments designed to assess the release kinetics suggest that a linear driving force model is capable of describing the release process and mass transfer coefficients are constant through the reactive life of the emulsion. The release kinetics in emulsions containing MgO particles were found to be three orders of magnitude faster than those quantified for emulsions containing CaCO3. The slower release kinetics of the emulsions containing CaCO3 particles may prove beneficial when considering pH control at sites

Rheology of attractive emulsions.

Science.gov (United States)

Datta, Sujit S; Gerrard, Dustin D; Rhodes, Travers S; Mason, Thomas G; Weitz, David A

2011-10-01

We show how attractive interactions dramatically influence emulsion rheology. Unlike the repulsive case, attractive emulsions below random close packing, φ(RCP), can form soft gel-like elastic solids. However, above φ(RCP), attractive and repulsive emulsions have similar elasticities. Such compressed attractive emulsions undergo an additional shear-driven relaxation process during yielding. Our results suggest that attractive emulsions begin to yield at weak points through the breakage of bonds, and, above φ(RCP), also undergo droplet configurational rearrangements.

Design of an Emulsion-based Personal Detergent through a Model-based Chemical Product Design Methodology

DEFF Research Database (Denmark)

Mattei, Michele; Hill, Michael; Kontogeorgis, Georgios

2013-01-01

An extended systematic methodology for the design of emulsion-based Chemical products is presented. The methodology consists of a model-based framework involving seven sequential hierarchical steps: starting with the identification of the needs to be satisfied by the product and then adding one-b...... to obtain one or more candidate formulations. A conceptual casestudy representing a personal detergent is presented to highlight the methodology....

Design of an Emulsion-based Personal Detergent through a Model-based Chemical Product Design Methodology

DEFF Research Database (Denmark)

Mattei, Michele; Hill, Michael; Kontogeorgis, Georgios

2013-01-01

An extended systematic methodology for the design of emulsion-based Chemical products is presented. The methodology consists of a model-based framework involving seven sequential hierarchical steps: starting with the identification of the needs to be satisfied by the product and then adding one...... to obtain one or more candidate formulations. A conceptual casestudy representing a personal detergent is presented to highlight the methodology....

Bonding auto-polymerising acrylic resin to acrylic denture teeth.

LENUS (Irish Health Repository)

Nagle, Susan

2009-09-01

This study investigated the effect of surface treatments on the shear bond strength of an auto-polymerising acrylic resin cured to acrylic denture teeth. The surface treatments included a combination of grit-blasting and\\/or wetting the surface with monomer. Samples were prepared and then stored in water prior to shear testing. The results indicated that the application of monomer to the surface prior to bonding did not influence the bond strength. Grit blasting was found to significantly increase the bond strength.

Mixing Time, Inversion and Multiple Emulsion Formation in a Limonene and Water Pickering Emulsion

Directory of Open Access Journals (Sweden)

Laura Sawiak

2018-05-01

Full Text Available It has previously been demonstrated that particle-stabilized emulsions comprised of limonene, water and fumed silica particles exhibit complex emulsification behavior as a function of composition and the duration of the emulsification step. Most notably the system can invert from being oil-continuous to being water-continuous under prolonged mixing. Here we investigate this phenomenon experimentally for the regime where water is the majority liquid. We prepare samples using a range of different emulsification times and we examine the final properties in bulk and via confocal microscopy. We use the images to quantitatively track the sizes of droplets and clusters of particles. We find that a dense emulsion of water droplets forms initially which is transformed, in time, into a water-in-oil-in-water multiple emulsion with concomitant changes in droplet and cluster sizes. In parallel we carry out rheological studies of water-in-limonene emulsions using different concentrations of fumed silica particles. We unite our observations to propose a mechanism for inversion based on the changes in flow properties and the availability of particles during emulsification.

Radiation-induced graft copolymerization of methyl acrylate and acrylic acid onto rubber wood fiber

International Nuclear Information System (INIS)

Saliza Jam; Mansor Ahmad; Wan Md Zin Wan Yunus; Khairul Zaman Mohd Dahlan

2001-01-01

Graft copolymerization of methyl acrylate and acrylic acid monomers onto rubber wood fiber (RWF) was carried out by simultaneous radiation-induced technique. The parameters affecting the grafting reaction were investigated and the optimum conditions for both monomers obtained are as follows: impregnation time = 16 hours, total dose = 30 kGy, methanol : water ratio, 3:1, monomers concentration = 40 v/v % and sulphuric acid concentration = 0.1 mol/L. Fourier Transform Infrared (FTIR), thermogravimetry analysis (TGA), and scanning electron microscope (SEM) analyses used to characterize graft copolymers. The structural investigation by x-ray diffraction (XRD) shows the degree of crystallinity of rubber wood fiber decreased with the incorporation of poly(methyl acrylate) and poly(acrylic acid) grafts. (Author)

A comparison of the stability of beverage cloud emulsions formulated with different gum acacia- and starch-based emulsifiers.

Science.gov (United States)

Reiner, S J; Reineccius, G A; Peppard, T L

2010-06-01

The performance of several hydrocolloids (3 gum acacias, 1 modified gum acacia, and 3 modified starches) in stabilizing beverage emulsions and corresponding model beverages was investigated employing different core materials, emulsifier usage levels, and storage temperatures. Concentrated emulsions were prepared using orange terpenes or Miglyol 812 (comprising medium-chain triglycerides, MCT) weighted 1:1 with ester gum, stored at 25 or 35 degrees C, and analyzed on days 0, 1, and 3. On day 3, model beverages were made from each emulsion, stored at both temperatures, and analyzed weekly for 4 wk. Stability of concentrated emulsions was assessed by measuring mean particle size and by visual observations of ringing; beverage stability was judged similarly and also by loss of turbidity. Particle size measurements showed concentrated emulsions containing gum acacia or modified gum acacia with either core material were stable over 3 d storage at both temperatures whereas those made with modified starches were not, destabilization being faster at 35 degrees C. Beverages based on orange terpenes, in contrast to Miglyol, yielded smaller mean particle sizes, both on manufacture and during storage, regardless of hydrocolloid used. Visual observations of ringing generally supported this finding. Modified gum acacia was evaluated at both recommended and higher usage levels, stability increasing in the latter case. In general, all gum acacia and modified gum acacia emulsifiers were superior in stability to those based on modified starches, at either temperature, for orange terpene-based beverages. In Miglyol-based beverages, similar results were seen, except 1 modified starch performed as well as the gum acacia products.

Endocytosis of Corn Oil-Caseinate Emulsions In Vitro: Impacts of Droplet Sizes

Science.gov (United States)

Fan, Yuting; Yokoyama, Wally; Yi, Jiang

2017-01-01

The relative uptake and mechanisms of lipid-based emulsions of three different particle diameters by Caco-2 cells were studied. The corn oil-sodium caseinate emulsions showed little or no cytotoxicity even at 2 mg/mL protein concentration for any of the three droplet size emulsions. Confocal laser scanning microscopy (CLSM) of Nile red containing emulsions showed that the lipid-based emulsions were absorbed by Caco-2 cells. A negative correlation between the mean droplet size and cellular uptake was observed. There was a time-dependent and energy-dependent uptake as shown by incubation at different times and treatment with sodium azide a general inhibitor of active transport. The endocytosis of lipid-based emulsions was size-dependent. The internalization of nanoemulsion droplets into Caco-2 cells mainly occurred through clathrin- and caveolae/lipid raft-related pathways, while macropinocytosis route played the most important role for 556 nm emulsion endocytosis as shown by the use of specific pathway inhibitors. Permeability of the emulsion through the apical or basal routes also suggested that active transport may be the main route for lipid-based nanoemulsions. The results may assist in the design and application of lipid-based nanoemulsions in nutraceuticals and pharmaceuticals delivery. PMID:29072633

Endocytosis of Corn Oil-Caseinate Emulsions In Vitro: Impacts of Droplet Sizes

Directory of Open Access Journals (Sweden)

Yuting Fan

2017-10-01

Full Text Available The relative uptake and mechanisms of lipid-based emulsions of three different particle diameters by Caco-2 cells were studied. The corn oil-sodium caseinate emulsions showed little or no cytotoxicity even at 2 mg/mL protein concentration for any of the three droplet size emulsions. Confocal laser scanning microscopy (CLSM of Nile red containing emulsions showed that the lipid-based emulsions were absorbed by Caco-2 cells. A negative correlation between the mean droplet size and cellular uptake was observed. There was a time-dependent and energy-dependent uptake as shown by incubation at different times and treatment with sodium azide a general inhibitor of active transport. The endocytosis of lipid-based emulsions was size-dependent. The internalization of nanoemulsion droplets into Caco-2 cells mainly occurred through clathrin- and caveolae/lipid raft-related pathways, while macropinocytosis route played the most important role for 556 nm emulsion endocytosis as shown by the use of specific pathway inhibitors. Permeability of the emulsion through the apical or basal routes also suggested that active transport may be the main route for lipid-based nanoemulsions. The results may assist in the design and application of lipid-based nanoemulsions in nutraceuticals and pharmaceuticals delivery.

Synthesis of Poly(styrene-acrylates-acrylic acid Microspheres and Their Chemical Composition towards Colloidal Crystal Films

Directory of Open Access Journals (Sweden)

Luis A. Ríos-Osuna

2016-01-01

Full Text Available In this paper, polystyrene colloidal microspheres have been prepared using hexyl acrylate (HA, ethylhexyl acrylate (EHA, isooctyl acrylate (IOA, butyl acrylate (BA, or isobutyl acrylate (IBA as comonomers. Microspheres with diameters from 212 to 332 nm and with a polystyrene content of 65–78% were prepared. The particles prepared in this work do not present the typical core-shell structure; as a consequence, DSC analysis showed that the microspheres exhibited only one Tg. TEM images show that the particles with comonomer content below ~30% were spherical and regular. Microspheres containing comonomer between 21 to 25% produced the less brittle films showing very iridescent colors. The films prepared from microspheres containing hexyl, ethylhexyl, and isooctyl acrylate as comonomers are firmly attached to the substrate due to their adhesive properties. The large decrease of the fragility observed in these films makes them much more attractive materials in sensing applications.

Advances in acrylic-alkyd hybrid synthesis and characterization

Science.gov (United States)

Dziczkowski, Jamie

2008-10-01

performance. Reversible-addition fragmentation polymerization techniques were employed to create a new class of acrylic-alkyd hybrid materials. Medium and long oil alkyds made from the monoglyceride process using soybean oil, glycerol, and phthalic anhydride were modified with a RAFT chain transfer agent. The alkyd macro-RAFT agents were reached by end-capping a medium oil soya-based alkyd with a carboxy-functional trithiocarbonate. The alkyd macro-RAFT agents were then used to create acrylic-alkyd block structures by polymerizing different acrylic monomers, including both acrylates and methacrylates in the presence of the macro-RAFT agent and 2, 2'-azobisisobutyronitrile (AIBN). Co-acrylic segments were reached by complete polymerization of one monomer followed by the addition of a second monomer and additional free radical initiator. The alkyds, macro-RAFT agents and, acrylic-alkyd blocks were characterized by size-exclusion chromatography (SEC), FTIR, and 1H-NMR. Pseudo-first-order kinetics behavior and conversion vs. molecular weight plots show that the RAFT-mediated reaction afforded a more controlled process for the synthesis of acrylated-alkyd materials. Preliminary coatings tests showed that material properties of acrylated-alkyds achieved by RAFT polymerization exhibit good overall coatings properties including adhesion, gloss, hardness, and impact resistance.

Mathematical Approach in Rheological Characterizing of Asphalt Emulsion Residues

Directory of Open Access Journals (Sweden)

Seong Hwan Cho

2015-01-01

Full Text Available Three different emulsion residues, such as SS1HP, HFE90, and SS-1VH (trackless, and a base asphalt binder (PG 64-22 are compared to characterize rheological properties by using DSR test. In order to capture the emulsion properties, different frequencies (from 1 to 100 rad/sec at a 10% constant shear rate and temperatures (from −45°C to 75°C with 15°C increments were applied. Then, a master curve for shear modulus was plotted for each emulsion. The transition of the HFE90 emulsion from viscous to elastic behavior occurs at lower temperatures, compared to the other materials. This emulsion is known for performing in a wider temperature range as shown in the results. The trackless emulsion presents an elastic behavior at intermediate temperatures. This product is known as having very fast setting and high resistance to shear stresses. The trackless emulsion presents the highest viscous and elastic modulus, followed by the PG 64-22 binder, SS1HP, and HFE90 emulsion. Shear strength test results show a behavior between trackless emulsion and SS1HP similar to the frequency sweep test results performed by DSR.

[Nasal submicron emulsion of Scutellariae Radix extract preparation technology research based on phase transfer of solute technology].

Science.gov (United States)

Shi, Ya-jun; Shi, Jun-hui; Chen, Shi-bin; Yang, Ming

2015-07-01

Based on the demand of nasal drug delivery high drug loadings, using the unique phase transfer of solute, integrating the phospholipid complex preparation and submicron emulsion molding process of Scutellariae Radix extract, the study obtained the preparation of the high drug loadings submicron emulsion of Scutellariae Radix extract. In the study of drug solution dispersion method, the uniformity of drug dispersed as the evaluation index, the traditional mixing method, grinding, homogenate and solute phase transfer technology were investigated, and the solute phase transfer technology was adopted in the last. With the adoption of new technology, the drug loading capacity reached 1.33% (phospholipid complex was 4%). The drug loading capacity was improved significantly. The transfer of solute method and timing were studied as follows,join the oil phase when the volume of phospholipid complex anhydrous ethanol solution remaining 30%, the solute phase transfer was completed with the continued recycling of anhydrous ethanol. After drug dissolved away to oil phase, the preparation technology of colostrum was determined with the evaluation index of emulsion droplet form. The particle size of submicron emulsion, PDI and stability parameters were used as evaluation index, orthogonal methodology were adopted to optimize the submicron emulsion ingredient and main influential factors of high pressure homogenization technology. The optimized preparation technology of Scutellariae Radix extract nasal submicron emulsion is practical and stable.

Phase behaviour and microstructure of the micro-emulsions composed of cholinium-based ionic liquid, Triton X-100 and water

International Nuclear Information System (INIS)

Pei, Yuanchao; Huang, Yanjie; Li, Lin; Wang, Jianji

2014-01-01

Highlights: • The microemulsions composed of cholinium-based ionic liquid, Triton X-100 and water have been prepared and characterised. • Ternary phase diagrams of the microemulsions have been established at T = 298.15 K. • The microemulsions exhibit IL-in-water, bicontinuous and water-in-IL microstructures. • Droplets with the size smaller than 20 nm are formed in these IL-based microemulsions. - Abstract: In this paper, micro-emulsions composed of cholinium-based ionic liquids (ILs), octylphenol ethoxylate (Triton X-100) and water were prepared. These ternary systems were found to be stable over 12 months at room temperature. Their phase behaviour was investigated by using cloud titrations, and their microstructures were characterised by means of cyclic voltammetry and electrical conductance measurements at T = 298.15 K. It was shown that the micro-emulsions exhibited IL-in-water, bi-continuous and water-in-IL microstructures. Dynamic light scattering data suggest that Triton X-100 forms micelles in water, which were swelled by the ILs added. Droplets with the size about 20 nm were formed in these IL-based micro-emulsions, and the droplet size increased with the increase of the IL concentrations. These IL-based micro-emulsions may have potential in drug delivery, chemical reactions and nanomaterial preparation as a new type of nanoreactors

Antimicrobial activity of poly(acrylic acid) block copolymers

Energy Technology Data Exchange (ETDEWEB)

Gratzl, Günther, E-mail: guenther.gratzl@jku.at [Johannes Kepler University Linz, Institute for Chemical Technology of Organic Materials, Altenberger Str. 69, 4040 Linz (Austria); Paulik, Christian [Johannes Kepler University Linz, Institute for Chemical Technology of Organic Materials, Altenberger Str. 69, 4040 Linz (Austria); Hild, Sabine [Johannes Kepler University Linz, Institute of Polymer Science, Altenberger Str. 69, 4040 Linz (Austria); Guggenbichler, Josef P.; Lackner, Maximilian [AMiSTec GmbH and Co. KG, Leitweg 13, 6345 Kössen, Tirol (Austria)

2014-05-01

The increasing number of antibiotic-resistant bacterial strains has developed into a major health problem. In particular, biofilms are the main reason for hospital-acquired infections and diseases. Once formed, biofilms are difficult to remove as they have specific defense mechanisms against antimicrobial agents. Antimicrobial surfaces must therefore kill or repel bacteria before they can settle to form a biofilm. In this study, we describe that poly(acrylic acid) (PAA) containing diblock copolymers can kill bacteria and prevent from biofilm formation. The PAA diblock copolymers with poly(styrene) and poly(methyl methacrylate) were synthesized via anionic polymerization of tert-butyl acrylate with styrene or methyl methacrylate and subsequent acid-catalyzed hydrolysis of the tert-butyl ester. The copolymers were characterized via nuclear magnetic resonance spectroscopy (NMR), size-exclusion chromatography (SEC), Fourier transform infrared spectroscopy (FTIR), elemental analysis, and acid–base titrations. Copolymer films with a variety of acrylic acid contents were produced by solvent casting, characterized by atomic force microscopy (AFM) and tested for their antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. The antimicrobial activity of the acidic diblock copolymers increased with increasing acrylic acid content, independent of the copolymer-partner, the chain length and the nanostructure. - Highlights: • Acrylic acid diblock copolymers are antimicrobially active. • The antimicrobial activity depends on the acrylic acid content in the copolymer. • No salts, metals or other antimicrobial agents are needed.

Antimicrobial activity of poly(acrylic acid) block copolymers

International Nuclear Information System (INIS)

Gratzl, Günther; Paulik, Christian; Hild, Sabine; Guggenbichler, Josef P.; Lackner, Maximilian

2014-01-01

The increasing number of antibiotic-resistant bacterial strains has developed into a major health problem. In particular, biofilms are the main reason for hospital-acquired infections and diseases. Once formed, biofilms are difficult to remove as they have specific defense mechanisms against antimicrobial agents. Antimicrobial surfaces must therefore kill or repel bacteria before they can settle to form a biofilm. In this study, we describe that poly(acrylic acid) (PAA) containing diblock copolymers can kill bacteria and prevent from biofilm formation. The PAA diblock copolymers with poly(styrene) and poly(methyl methacrylate) were synthesized via anionic polymerization of tert-butyl acrylate with styrene or methyl methacrylate and subsequent acid-catalyzed hydrolysis of the tert-butyl ester. The copolymers were characterized via nuclear magnetic resonance spectroscopy (NMR), size-exclusion chromatography (SEC), Fourier transform infrared spectroscopy (FTIR), elemental analysis, and acid–base titrations. Copolymer films with a variety of acrylic acid contents were produced by solvent casting, characterized by atomic force microscopy (AFM) and tested for their antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. The antimicrobial activity of the acidic diblock copolymers increased with increasing acrylic acid content, independent of the copolymer-partner, the chain length and the nanostructure. - Highlights: • Acrylic acid diblock copolymers are antimicrobially active. • The antimicrobial activity depends on the acrylic acid content in the copolymer. • No salts, metals or other antimicrobial agents are needed

A Hydrogen Ion-Selective Sensor Based on Non-Plasticised Methacrylic-acrylic Membranes

Directory of Open Access Journals (Sweden)

Musa Ahmad

2002-08-01

Full Text Available A methacrylic-acrylic polymer was synthesised for use as a non-plasticised membrane for hydrogen ion-selective sensor incorporating tridodecylamine as an ionophore. The copolymer consisted of methyl methacrylate and n-butyl acrylate monomers in a ratio of 2:8. Characterisation of the copolymer using FTNMR demonstrated that the amount of each monomer incorporated during solution polymerisation was found to be similar to the amount used in the feed before polymerisation. The glass transition temperature of the copolymer determined by differential scanning calorimetry was -30.9 ºC. Potentiometric measurements conducted showed a linear pH response range of 4.3 – 9.6 with the response slope of 56.7 mV/decade. The selectivity of the sensors towards hydrogen ions was similar to other plasticiser based membrane electrodes and the logarithmic selectivity coefficients for discrimination against interference cations is close to –9.7. However, the incorporation of a lipophilic anion as membrane additive is essential in ensuring optimum performance of the hydrogen ion sensor.

Preparation of poly(acrylamide-co-acrylic acid)-grafted gum and its flocculation and biodegradation studies.

Science.gov (United States)

Mittal, H; Mishra, Shivani B; Mishra, A K; Kaith, B S; Jindal, R; Kalia, S

2013-10-15

Biodegradation studies of Gum ghatti (Gg) and acrylamide-co-acrylic acid based flocculants [Gg-cl-poly(AAm-co-AA)] have been reported using the soil composting method. Gg-cl-poly(AAm-co-AA) was found to degrade 89.76% within 60 days. The progress of biodegradation at each stage was monitored through FT-IR and SEM. Polymer was synthesized under pressure using potassium persulphate-ascorbic acid as a redox initiator and N,N'-methylene-bis-acrylamide as a crosslinker. Synthesized polymer was found to show pH, temperature and ionic strength of the cations dependent swelling behavior. Gg-cl-poly(AAm-co-AA) was utilized for the selective absorption of saline from different petroleum fraction-saline emulsions. The flocculation efficiency of the polymer was studied as a function of polymer dose, temperature and pH of the solution. Gg-cl-poly(AAm-co-AA) showed maximum flocculation efficiency with 20 mol L(-1) polymer dose in acidic medium at 50 °C. Copyright © 2013. Published by Elsevier Ltd.

Fabrication and Properties of polyacrylic acid by ionic surfactant disturbance method

Science.gov (United States)

Lawan, S.; Osotchan, T.; Chuajiw, W.; Subannajui, K.

2017-09-01

The formation of polymeric materials can be achieved by several methods such as melting and casting, screw extrusion, cross-linking of resin or rubber in a mold, and so on. In this work, the polyacrylic acid is formed by using the emulsion disturbance method. Despite extensively used in the colour painting and coating industries, acrylic emulsion can be processed into a foam and powder configuration by a reaction between acrylic emulsion and salt. The solidification hardly changes the volume between liquid emulsion and solidified polymer which means the final structure of polyacrylic acid is filled with opened air cells. The opened air cell structure is confirmed by the result from scanning electron microscopy. The chemical analysis and crystallography of acrylic powder and foam are examined by Fourier-transform infrared spectroscopy and X-ray diffraction respectively. The phase transformation and Thermal stability are studied by differential scanning calorimetry and thermo gravimetric analysis. Moreover, the mechanical properties of acrylic foam were observed by tensile, compressive and hardness test. In addition to the basic property analysis, acrylic foam was also used in the particle filtration application.

Quantifying Asphalt Emulsion-Based Chip Seal Curing Times Using Electrical Resistance Measurements.

Science.gov (United States)

2017-04-15

Chip sealing typically consists of covering a pavement surface with asphalt emulsion into which aggregate chips are embedded. The asphalt emulsion cures through the evaporation of water, thus providing mechanical strength to adhere to the pavement wh...

Poly(lauryl acrylate) and poly(stearyl acrylate) grafted multiwalled carbon nanotubes for polypropylene composites

DEFF Research Database (Denmark)

Daugaard, Anders Egede; Jankova Atanasova, Katja; Hvilsted, Søren

2014-01-01

Two new polymer grafts on an industrial grade multiwalled carbon nanotube (MWCNT) were prepared through a non-oxidative pathway employing controlled free radical polymerization for surface initiated polymer grafting. After photochemical introduction of an ATRP initiator onto the MWCNT......, polymerizations of lauryl or stearyl acrylate were performed, resulting in two novel polymer modifications on the MWCNT (poly(lauryl acrylate) or poly(stearyl acrylate)). The method was found to give time dependent loading of polymers as a function of time (up to 38 wt% for both acrylates), and showed a plateau...... in loading after 12 h of polymerization. The modified nanomaterials were melt mixed into polypropylene composites with very low filler loading (0.3 wt%), whereafter both the thermal and electrical properties were investigated by DSC and dielectric resonance spectroscopy. The electrical properties were found...

Lipid oxidation in base algae oil and water-in-algae oil emulsion: Impact of natural antioxidants and emulsifiers.

Science.gov (United States)

Chen, Bingcan; Rao, Jiajia; Ding, Yangping; McClements, David Julian; Decker, Eric Andrew

2016-07-01

The impact of natural hydrophilic antioxidants, metal chelators, and hydrophilic antioxidant/metal chelator mixture on the oxidative stability of base algae oil and water-in-algae oil emulsion was investigated. The results showed that green tea extract and ascorbic acid had greatest protective effect against algae oil oxidation and generated four day lag phase, whereas rosmarinic acid, grape seed extract, grape seed extract polymer, deferoxamine (DFO), and ethylenediaminetetraacetic acid (EDTA) had no significant protective effect. Besides, there was no synergistic effect observed between natural antioxidants and ascorbic acid. The emulsifiers are critical to the physicochemical stability of water-in-algae oil emulsions. Polyglycerol polyricinoleate (PGPR) promoted the oxidation of emulsion. Conversely, the protective effect on algae oil oxidation was appreciated when defatted soybean lecithin (PC 75) or defatted lyso-lecithin (Lyso-PC) was added. The role of hydrophilic antioxidants in emulsion was similar to that in algae oil except EDTA which demonstrated strong antioxidative effect in emulsion. The results could provide information to build up stable food products containing polyunsaturated fatty acids (PUFA). Copyright © 2016 Elsevier Ltd. All rights reserved.

40 CFR 721.405 - Polyether acrylate.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Polyether acrylate. 721.405 Section... § 721.405 Polyether acrylate. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a polyether acrylate (PMN P-95-666) is subject to...

Brown Coal Dewatering Using Poly (Acrylamide-Co-Potassium Acrylic Based Super Absorbent Polymers

Directory of Open Access Journals (Sweden)

Sheila Devasahayam

2015-09-01

Full Text Available With the rising cost of energy and fuel oils, clean coal technologies will continue to play an important role during the transition to a clean energy future. Victorian brown coals have high oxygen and moisture contents and hence low calorific value. This paper presents an alternative non evaporative drying technology for high moisture brown coals based on osmotic dewatering. This involves contacting and mixing brown coal with anionic super absorbent polymers (SAP which are highly crossed linked synthetic co-polymers based on a cross-linked copolymer of acryl amide and potassium acrylate. The paper focuses on evaluating the water absorption potential of SAP in contact with 61% moisture Loy Yang brown coal, under varying SAP dosages for different contact times and conditions. The amount of water present in Loy Yang coal was reduced by approximately 57% during four hours of SAP contact. The extent of SAP brown coal drying is directly proportional to the SAP/coal weight ratio. It is observed that moisture content of fine brown coal can readily be reduced from about 59% to 38% in four hours at a 20% SAP/coal ratio.

Charm studies in emulsion

CERN Document Server

Kalinin, Sergey

Neutrino-nucleon scattering is an effective way to investigate the inner structure of the nucleon, to extract the Standard Model parameters and to explore heavy quarks production dynamics. In the last decades, several experiments have been constructed to study weak interactions of neutrinos with nucleons. One of them was CERN-WA95 experiment operated by the CHORUS collaboration. It is based on a hybrid detector with nuclear emulsion as a target followed by electronic devices. Nuclear emulsion provides three dimensional spatial information with an outstanding resolution of the order of one micron. Therefore, it is ideal to detect short-lived particles. A special technique has been developed to reconstruct events in the emulsion which allows to perform a detailed investigation of events such as charmed hadrons production by neutrinos. As a result, the backround in the selected charm sample is up to six times lower compared to similar experiments. Such a method also permits to make direct measurements of some qu...

Histidine-functionalized carbon-based dot-Zinc(II) nanoparticles as a novel stabilizer for Pickering emulsion synthesis of polystyrene microspheres.

Science.gov (United States)

Ruiyi, Li; Zaijun, Li; Junkang, Liu

2017-05-01

Carbon-based dots (CDs) are nanoparticles with size-dependent optical and electronic properties that have been widely applied in energy-efficient displays and lighting, photovoltaic devices and biological markers. However, conventional CDs are difficult to be used as ideal stabilizer for Pickering emulsion due to its irrational amphiphilic structure. The study designed and synthesized a new histidine-functionalized carbon dot-Zinc(II) nanoparticles, which is termed as His-CD-Zn. The His-CD was made via one-step hydrothermal treatment of histidine and maleic acid. The His-CD reacted with Zn 2+ to form His-CD-Zn. The as-prepared His-CD-Zn was used as a solid particle surfactant for stabilizing styrene-in-water emulsion. The Pickering emulsion exhibits high stability and sensitive pH-switching behaviour. The introduction of S 2 O 8 2- triggers the emulsion polymerization of styrene. The resulted polystyrene microsphere was well coated with His-CDs on the surface. It was successfully used as an ideal adsorbent for removal of heavy metallic ions from water with high adsorption capacity. The study also provides a prominent approach for fabrication of amphiphilic carbon-based nanoparticles for stabilizing Pickering emulsion. Copyright © 2017 Elsevier Inc. All rights reserved.

Structural degradation of acrylic bone cements due to in vivo and simulated aging.

Science.gov (United States)

Hughes, Kerry F; Ries, Michael D; Pruitt, Lisa A

2003-05-01

Acrylic bone cement is the primary load-bearing material used for the attachment of orthopedic devices to adjoining bone. Degradation of acrylic-based cements in vivo results in a loss of structural integrity of the bone-cement-prosthesis interface and limits the longevity of cemented orthopedic implants. The purpose of this study is to investigate the effect of in vivo aging on the structure of the acrylic bone cement and to develop an in vitro artificial aging protocol that mimics the observed degradation. Three sets of retrievals are examined in this study: Palacos brand cement retrieved from hip replacements, and Simplex brand cement retrieved from both hip and knee replacement surgeries. In vitro aging is performed using oxidative and acidic environments on three acrylic-based cements: Palacos, Simplex, and CORE. Gel permeation chromatography (GPC) and Fourier transform infrared spectroscopy (FTIR) are used to examine the evolution of molecular weight and chemical species within the acrylic cements due to both in vivo and simulated aging. GPC analysis indicates that molecular weight is degraded in the hip retrievals but not in the knee retrievals. Artificial aging in an oxidative environment best reproduces this degradation mechanism. FTIR analysis indicates that there exists a chemical evolution within the cement due to in vivo and in vitro aging. These findings are consistent with scission-based degradation schemes in the cement. Based on the results of this study, a pathway for structural degradation of acrylic bone cement is proposed. The findings from this investigation have broad applicability to acrylic-based cements and may provide guidance for the development of new bone cements that resist degradation in the body. Copyright 2003 Wiley Periodicals, Inc.

Radiation Synthesis of PEGDA and Acrylated Palm Oil Nanosized Gel for Bioactives Immobilization

International Nuclear Information System (INIS)

Hamzah, M.Y.; Tajau, R.; Dahlan, K.Z. Mohd; Mahmood, M.H.; Hashim, K.

2010-01-01

The use of microemulsion in the development of nanosized gel based on polyethylene glycol diacrylate (PEGDA) and acrylated palm oil (APO) is demonstrated. PEGDA was solubilized in n-heptane with use of AOT at 0.15M concentration to form reverse micelles, while APO was solubilized with SDS in water to form direct micelles. Both of these systems were depicted by means of ternary phase diagram. These micelles were than irradiated at 1,3,5,10,15 and 30kGy using gamma irradiation or EB to crosslink the entrapped polymer in the micelles. Ionizing radiation was imparted to the emulsions to generate crosslinking reactions in the micelles formed. The nanosized gel was evaluated in terms of particle diameter using dynamic light scattering and the images of the nanosized gel were studied using transmission electron microscopy (TEM). Results show that the size, charge and shape of the particles are influenced by concentration of surfactants and radiation dose. This study showed that this method can be utilized to produce nanosized gel. Future work include the attachment of functional group to the nano sized gel, loading of drug such as curcumin and further characterization using dynamic light scattering. (author)

Radiation Synthesis of PEGDA and Acrylated Palm Oil Nanosized Gel for Bioactives Immobilization

Energy Technology Data Exchange (ETDEWEB)

Hamzah, M. Y.; Tajau, R.; Dahlan, K.Z. Mohd; Mahmood, M. H.; Hashim, K., E-mail: m_yusof@nuclearmalaysia.gov.my [Makmal Nanoteknologi, Blok 64, BTS, Jafan Denghil, Agensi Nuklear Malaysia, Bangi 43000 Kajang, Selangor (Malaysia)

2010-07-01

The use of microemulsion in the development of nanosized gel based on polyethylene glycol diacrylate (PEGDA) and acrylated palm oil (APO) is demonstrated. PEGDA was solubilized in n-heptane with use of AOT at 0.15M concentration to form reverse micelles, while APO was solubilized with SDS in water to form direct micelles. Both of these systems were depicted by means of ternary phase diagram. These micelles were than irradiated at 1,3,5,10,15 and 30kGy using gamma irradiation or EB to crosslink the entrapped polymer in the micelles. Ionizing radiation was imparted to the emulsions to generate crosslinking reactions in the micelles formed. The nanosized gel was evaluated in terms of particle diameter using dynamic light scattering and the images of the nanosized gel were studied using transmission electron microscopy (TEM). Results show that the size, charge and shape of the particles are influenced by concentration of surfactants and radiation dose. This study showed that this method can be utilized to produce nanosized gel. Future work include the attachment of functional group to the nano sized gel, loading of drug such as curcumin and further characterization using dynamic light scattering. (author)

In-situ Fabrication of a Freestanding Acrylate-based Hierarchical Electrolyte for Lithium-sulfur Batteries

International Nuclear Information System (INIS)

Liu, M.; Jiang, H.R.; Ren, Y.X.; Zhou, D.; Kang, F.Y.; Zhao, T.S.

2016-01-01

Graphical abstract: We present a freestanding acrylate-based hierarchical electrolyte. This quasi-solid electrolyte is assembled by in-situ gelation of a pentaerythritol tetraacrylate (PETEA)-based gel polymer electrolyte (GPE) into a polymethyl methacrylate (PMMA)-based electrospun network. The prepared polymer battery renders a suppressed shuttle effect and much enhanced cycle life. - Highlights: • A freestanding Acrylate-based Hierarchical Electrolyte was in-situ crafted. • The high conductivity is due to strong uptake ability and elimination of separator. • The polymer battery renders a superior high rate capability and excellent retention. • First-principle calculations prove anchoring ability of ester functional groups. • Cell modeling shows geometric design effectively suppresses polysulfide flux. - Abstract: A number of methods have been attempted to suppress the shuttle effect in lithium-sulfur (Li-S) batteries to improve battery performance. Conventional methods, however, reduce the ionic conductivity, sacrifice the overall energy density and increase the cost of production. Here, we report a facile synthesis of an acrylate-based hierarchical electrolyte (AHE). This quasi-solid electrolyte is assembled by in-situ gelation of a pentaerythritol tetraacrylate (PETEA)-based gel polymer electrolyte (GPE) into a polymethyl methacrylate (PMMA)-based electrospun network. The structural similarity and synergetic compatibility between the electrospun network and GPE provide the AHE an ester-rich robust structure with a high ionic conductivity of 1.02 × 10 −3 S cm −1 due to the strong uptake ability and the elimination of commercial separator. The S/AHE/Li polymer battery also renders a high rate capability of 645 mAh g −1 at 3C, while maintaining excellent retention at both high and low current densities (80.3% after 500 cycles at 0.3C and 91.9% after 500 cycles at 3C). First-principle calculations reveal that the reduced shuttle effect can be

The evolution of palm oil acrylates within 20 years in Nuclear Malaysia

International Nuclear Information System (INIS)

Mek Zah Salleh; Rida Tajau; Nurul Huda Mudri

2016-01-01

Acrylated palm oil was synthesized from epoxidized palm oil (EPOP), in early 1989, through acrylation/methacrylation process at Radiation Technology Division laboratory. The acrylated products namely Epoxidized Palm Oil Acrylate/Methacrylate (EPOLA/ EPOMA), with the molecular weight around 2000-3000 g/mol, was found curable when subjected to UV or EB irradiations. Isocyanation of EPOLAs resulted in a resin called Palm Oil Based Urethane Acrylate (POBUA). POBUA possess certain advantages over EPOLA such as much higher molecular weight between 5000 to 20000 g/ mol, better curing speed, crosslinking density, higher abrasion resistance and also higher pendulum hardness. Hyper branched polyurethane acrylate (HBPUA) from palm oil oleic was synthesized by a three-step reaction in 2012. The reaction was confirmed by several analytical data; hydroxyl value (OHV), FTIR, GPC and NMR spectroscopy analyses. The thermal decomposition of HBPUA formulations shows good thermal stability up to 450 degree Celsius. (author)

Chemical modification of magnetite nanoparticles and preparation of acrylic-base magnetic nanocomposite particles via miniemulsion polymerization

Energy Technology Data Exchange (ETDEWEB)

Mahdieh, Athar; Mahdavian, Ali Reza, E-mail: a.mahdavian@ippi.ac.ir; Salehi-Mobarakeh, Hamid

2017-03-15

Nowadays, magnetic nanocomposite particles have attracted many interests because of their versatile applications. A new method for chemical modification of Fe{sub 3}O{sub 4} nanoparticles with polymerizable groups is presented here. After synthesis of Fe{sub 3}O{sub 4} nanoparticles by co-precipitation method, they were modified sequentially with 3-aminopropyl triethoxysilane (APTES), acryloyl chloride (AC) and benzoyl chloride (BC) and all were characterized by FTIR, XRD, SEM and TGA analyses. Then the modified magnetite nanoparticles with unsaturated acrylic groups were copolymerized with methyl methacrylate (MMA), butyl acrylate (BA) and acrylic acid (AA) through miniemulsion polymerization. Although several reports exist on preparation of magnetite-base polymer particles, but the efficiency of magnetite encapsulationwith reasonable content and obtaining final stable latexes with limited aggregation ofFe{sub 3}O{sub 4} are still important issues. These were considered here by controlling reaction parameters. Hence, a seriesofmagneticnanocomposites latex particlescontaining different amounts of Fe{sub 3}O{sub 4} nanoparticles (0–10 wt%) were prepared with core-shell morphology and diameter below 200 nm and were characterized by FT-IR, DSC and TGA analyses. Their morphology and size distribution were studied by SEM, TEM and DLS analyses too. Magnetic properties of all products were also measuredby VSM analysis and the results revealed almost superparamagnetic properties for the obtained nanocomposite particles. - Highlights: • Chemical modification of magnetite nanoparticles. • Encapsulation of modified magnetite with acrylic copolymer. • Superparamagnetic Fe3O4/polyacrylic nanocomposite particles.

Self-Assembled Colloidal Particle Clusters from In Situ Pickering-Like Emulsion Polymerization via Single Electron Transfer Mechanism.

Science.gov (United States)

Yuan, Jinfeng; Zhao, Weiting; Pan, Mingwang; Zhu, Lei

2016-08-01

A simple route is reported to synthesize colloidal particle clusters (CPCs) from self-assembly of in situ poly(vinylidene fluoride)/poly(styrene-co-tert-butyl acrylate) [PVDF/P(St-co-tBA)] Janus particles through one-pot seeded emulsion single electron transfer radical polymerization. In the in situ Pickering-like emulsion polymerization, the tBA/St/PVDF feed ratio and polymerization temperature are important for the formation of well-defined CPCs. When the tBA/St/PVDF feed ratio is 0.75 g/2.5 g/0.5 g and the reaction temperature is 35 °C, relatively uniform raspberry-like CPCs are obtained. The hydrophobicity of the P(St-co-tBA) domains and the affinity of PVDF to the aqueous environment are considered to be the driving force for the self-assembly of the in situ formed PVDF/P(St-co-tBA) Janus particles. The resultant raspberry-like CPCs with PVDF particles protruding outward may be promising for superhydrophobic smart coatings. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Novel high dielectric constant hybrid elastomers based on glycerol-insilicone emulsions

DEFF Research Database (Denmark)

Mazurek, Piotr Stanislaw; Skov, Anne Ladegaard

2016-01-01

Novel hybrid elastomers were prepared by speedmixing of two virtually immiscible liquids – glycerol and polydimethylsiloxane (PDMS) prepolymer. Upon crosslinking ofthe PDMS phase of the resulting glycerol-in-silicone emulsion freestanding films were obtained. In this way glycerol became uniformly...... elastomeractuators. Conductivities of samples based on various PDMS compositions with different loadings of embedded glycerol were thoroughly investigated providing useful information about the dielectric behavior....

Development of radiation curable surface coating based on soybean oil. part I. preparation and characterization of acrylated oil

International Nuclear Information System (INIS)

Ibrahim, M.S.; Said, H.M.; Moussa, I.M.

2005-01-01

An epoxy acrylate was synthesized from epoxidized soybean oil (ESOL) by using acrylic acid monomer. Triethyl amine (TEA) and hydroquinone were used as catalyst and inhibitor respectively. The epoxidized soybean oil acrylate (ESOLA) is done by introducing acrylic acid into oxirane groups of the epoxidized oil (ESOL). This reaction was confirmed by analytical data in terms of oxirane oxygen content, acid value, viscosity and spectroscopically analysis

Fish Oil-Based Fat Emulsion Reduces Acute Kidney Injury and Inflammatory Response in Antibiotic-Treated Polymicrobial Septic Mice

Directory of Open Access Journals (Sweden)

Juey-Ming Shih

2016-03-01

Full Text Available Acute kidney injury (AKI is a common complication in sepsis. This study compared the effects of a fish oil-based with a mixed oil fat emulsion on remote renal injury in an antibiotic-treated septic murine model. Mice were randomly assigned to a normal control (NC group and three septic groups. Sepsis was induced by cecal ligation and puncture (CLP. The antibiotic was injected intraperitoneally (IP after CLP and then daily till the time of sacrifice. Three hours after antibiotic treatment, one of the septic groups was injected IP with a fish oil-based emulsion (FO, while the other two groups were given either a mixed oil emulsion (MO or saline (SC. The septic groups were further divided into two separate time groups, with blood and kidneys samples collected at 24 h or 72 h post-CLP. The results showed that sepsis leads to the activation of neutrophils, T helper (Th1/Th-2/Th-17 and Treg cells (p < 0.05. Plasma NGAL and mRNA expressions of renal MyD88 and TLR4 were also enhanced (p < 0.05. Compared to the SC group, the group given the fish oil-based emulsion had decreased plasma NGAL by 22% and Treg by 33%. Furthermore, renal gene expressions of MyD88 and TLR4 reduced by 46% and 62%, respectively, whereas heat shock protein 70 and peroxisome proliferator-activated receptor-γ increased by 158% and 69%, respectively (p < 0.05, at Day 3 after CLP. These results suggest that administration of a fish oil-based emulsion has favorable effects, maintaining blood T cell percentage, downregulating Treg expression, attenuating systemic and local inflammation and offering renal protection under conditions of antibiotic-treated polymicrobial sepsis.

Beeswax–chitosan emulsion coated paper with enhanced water vapor barrier efficiency

International Nuclear Information System (INIS)

Zhang, Weiwei; Xiao, Huining; Qian, Liying

2014-01-01

Graphical abstract: - Highlights: • The water vapor barrier efficiency of paper was enhanced via green-based emulsion coating. • Extremely high lipid content in the emulsion coating layer was firstly utilized to reduce WVTR in emulsion-based film. • A controlled WVTR of beeswax–chitosan emulsion coating could be obtained by dying at specific temperature. - Abstract: For lipid–hydrocolloid emulsion based film, the increase of lipid amount would improve its water vapor barrier property, but also reduce the mechanical strength of the film in the meantime thus leading to a compromised lipid content in the film. However, when the emulsion is coated on paper surface, more lipid could be used for emulsion preparation to enhance the moisture resistance without considering the weakened strength of the film induced by lipid, because the mechanical properties of emulsion coated paper is mainly governed by the strength of base paper instead of the coating layer. In this study, beeswax–chitosan emulsion was first prepared and then coated on paper surface to improve paper's water vapor barrier and water resistance properties. The range and variance analysis of orthogonal test design showed that the order of priorities of the factors accordingly was beeswax solid content, drying temperature and chitosan concentration. The effect of drying temperature on water vapor transmission rate (WVTR) and water contact angle of coated paper was further investigated using 1.2 wt% chitosan and 96% beeswax solid content in the coating layer. The results indicated that water vapor barrier property was in accordance with the density of the coating layer. Atomic force microscope (AFM) was also used to characterize the surface morphology and explain the hydrophobicity of beeswax–chitosan coated paper. It was found that surface beeswax particles melted to wrinkle at high drying temperatures, while roughness values maintained at micro-scale over the temperature range investigated

Altering the level of calcium changes the physical properties and digestibility of casein-based emulsion gels.

Science.gov (United States)

McIntyre, Irene; O Sullivan, Michael; O Riordan, Dolores

2017-04-19

Casein-based emulsion gels prepared with different types of lipid (i.e. milk fat or rapeseed oil) were formulated with high (774 mg Ca per 100 g) or low (357 mg Ca per 100 g) calcium levels by blending acid and rennet casein. Their physicochemical characteristics (i.e. composition, texture, microstructure & water mobility) and in vitro digestibility were compared to conventionally formulated high-calcium (723 mg Ca per 100 g) emulsion gels made from rennet casein with calcium chelating salts (CCS). CCS-free, high-calcium emulsion gels were significantly (p ≤ 0.05) softer than those with low calcium levels (possibly due to their shorter manufacture time and higher pH) and showed the highest rates of disintegration during simulated gastric digestion. Despite having a higher moisture to protein ratio, the high-calcium emulsion gels containing CCS had broadly similar hardness values to those of high-calcium concentration prepared without CCS, but had higher cohesiveness. The high-calcium matrices containing CCS had quite a different microstructure and increased water mobility compared to those made without CCS and showed the slowest rate (p ≤ 0.05) of disintegration in the gastric environment. Gastric resistance was not affected by the type of lipid phase. Conversely, fatty acid release was similar for all emulsion gels prepared from milk fat, however, high-calcium emulsion gels (CCS-free) prepared from rapeseed oil showed higher lipolysis. Results suggest that food matrix physical properties can be modified to alter resistance to gastric degradation which may have consequences for the kinetics of nutrient release and delivery of bioactives sensitive to the gastric environment.

Sulfonated macro-RAFT agents for the surfactant-free synthesis of cerium oxide-based hybrid latexes.

Science.gov (United States)

Garnier, Jérôme; Warnant, Jérôme; Lacroix-Desmazes, Patrick; Dufils, Pierre-Emmanuel; Vinas, Jérôme; van Herk, Alex

2013-10-01

Three types of amphiphatic macro-RAFT agents were employed as compatibilizers to promote the polymerization reaction at the surface of nanoceria for the synthesis of CeO2-based hybrid latexes. Macro-RAFT copolymers and terpolymers were first synthesized employing various combinations of butyl acrylate as a hydrophobic monomer and acrylic acid (AA) and/or 2-acrylamido-2-methylpropane sulfonic acid (AMPS) as hydrophilic monomers. After characterizing the adsorption of these macro-RAFT agents at the cerium oxide surface by UV-visible spectrometry, emulsion copolymerization reactions of styrene and methyl acrylate were then carried out in the presence of the surface-modified nanoceria. Dynamic Light Scattering and cryo-Transmission Electron Microscopy were employed to confirm the hybrid structure of the final CeO2/polymer latexes, and proved that the presence of acrylic acid units in amphiphatic macro-RAFT agents enabled an efficient formation of hybrid structures, while the presence of AMPS units, when combined with AA units, resulted in a better distribution of cerium oxide nanoclusters between latex particles. Copyright © 2013 Elsevier Inc. All rights reserved.

How emulsions composition and structure affect sensory perception of low-viscosity model emulsions

NARCIS (Netherlands)

Vingerhoeds, M.H.; Wijk, de R.A.; Zoet, F.D.; Nixdorf, R.R.; Aken, van G.A.

2008-01-01

The oral residence time of low-viscosity emulsions, like milk, is relatively short. Despite this short residence time, people can easily perceive differences between these emulsions. Our research is dedicated to unravel the oral behaviour of emulsions in relation to sensory perception. The aim of

Physicochemical properties of peanut oil-based diacylglycerol and their derived oil-in-water emulsions stabilized by sodium caseinate.

Science.gov (United States)

Long, Zhao; Zhao, Mouming; Liu, Ning; Liu, Daolin; Sun-Waterhouse, Dongxiao; Zhao, Qiangzhong

2015-10-01

High purity peanut oil-based diacylglycerol (PO-DAG) (94.95 wt%) was prepared via enzymatic glycerolysis from peanut oil (PO). The resulting dominance of DAGs was proven to greatly influence the properties of corresponding fresh or frozen-thawed emulsions. Stable fresh oil-in-water emulsions were produced using either PO-DAG or PO, with stability enhanced by increased concentrations of Na-CN. The lower equilibrium interfacial tension along with greater negative ζ-potential of PO revealed that Na-CN was preferentially adsorbed to the PO interface. Adding 0.05 mol/L NaCl to the PO emulsions minimized depletion flocculation caused by the unadsorbed Na-CN, but further NaCl addition increased oil droplet size and concomitant coalescence. For the PO-DAG emulsions, adding 0.2 mol/L NaCl did not significantly (p>0.05) affect their ζ-potential but adding 0.05 or 0.1 mol/L NaCl lowered ζ-potential, although NaCl at these concentrations increased oil droplet size and coalescence. Freezing-thawing process considerably weakened the stability of PO-DAG emulsions. Copyright © 2015 Elsevier Ltd. All rights reserved.

Thermodynamics of swelling of latex particles with two monomers

NARCIS (Netherlands)

Maxwell, I.A.; Kurja, J.; van Doremaele, G.H.J.; German, A.L.

1992-01-01

The partitioning of 2 monomers between the latex particle, monomer droplet, and aq. phases of an emulsion polymer latex are measured at satn. swelling of the latex particle phase (corresponding to intervals I and II of an emulsion polymn.). The monomer (Me acrylate, Bu acrylate, styrene) and polymer

Fouling reduction by ozone-enhanced backwashing process in ultrafiltration of petroleum-based oil in water emulsion

Science.gov (United States)

Aryanti, Nita; Prihatiningtyas, Indah; Kusworo, Tutuk Djoko

2017-06-01

Ultrafiltration membrane has been successfully applied for oily waste water treatment. However, one significant drawback of membrane technology is fouling which is responsible for permeate flux decline as well as reducing membrane performance. One method commonly used to reduce fouling is a backwashing process. The backwashing is carried out by a push of reversed flow from permeate side to the feed side of a membrane to remove fouling on the membrane pore and release fouling release fouling layer on the external side. However, for adsorptive fouling, the backwashing process was not effective. On the other hand, Ozone demonstrated great performance for reducing organics fouling. Hence this research was focused on backwashing process with ozone for removing fouling due to ultrafiltration of petroleum based oil emulsion. Gasoline and diesel oil were selected as dispersed phase, while as continuous phase was water added with Tween 80 as a surfactant. This research found that the Ozone backwashing was effective to improve flux recovery. In ultrafiltration of gasoline emulsion, the flux recovery after Ozone backwashing was in the range of 42-74%. For ultrafiltration of diesel oil emulsion, the permeate flux recovery was about 35-84%. In addition, foulant deposition was proposed and predicting that foulant deposition for ultrafiltration of gasoline-in-water emulsion was surfactant as the top layer and the oil was underneath the surfactant. On the other hand, for ultrafiltration of diesel oil-in-water emulsion, the oil was predicted as a top layer above the surfactant foulant.

40 CFR 721.8082 - Polyester polyurethane acrylate.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Polyester polyurethane acrylate. 721... Substances § 721.8082 Polyester polyurethane acrylate. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as polyester polyurethane acrylate...

A Biosensor for Urea from Succinimide-Modified Acrylic Microspheres Based on Reflectance Transduction

Directory of Open Access Journals (Sweden)

Musa Ahmad

2011-08-01

Full Text Available New acrylic microspheres were synthesised by photopolymerisation where the succinimide functional group was incorporated during the microsphere preparation. An optical biosensor for urea based on reflectance transduction with a large linear response range to urea was successfully developed using this material. The biosensor utilized succinimide-modified acrylic microspheres immobilized with a Nile blue chromoionophore (ETH 5294 for optical detection and urease enzyme was immobilized on the surface of the microspheres via the succinimide groups. No leaching of the enzyme or chromoionophore was observed. Hydrolysis of the urea by urease changes the pH and leads to a color change of the immobilized chromoionophore. When the color change was monitored by reflectance spectrophotometry, the linear response range of the biosensor to urea was from 0.01 to 1,000 mM (R2 = 0.97 with a limit of detection of 9.97 mM. The biosensor response showed good reproducibility (relative standard deviation = 1.43%, n = 5 with no interference by major cations such as Na+, K+, NH4+ and Mg2+. The use of reflectance as a transduction method led to a large linear response range that is better than that of many urea biosensors based on other optical transduction methods.

Synthesis of Poly (Butyl Methacrylate/Butyl Acrylate) Highly Absorptive Resin Using Glow Discharge Electrolysis

International Nuclear Information System (INIS)

Li Yan; Yao Mengqi; Liao Ruirui; Yang Wu; Gao Jinzhang; Ren Jie

2014-01-01

A highly absorptive resin poly (butyl methacrylate (BMA)-co-butyl acrylate (BA)) was prepared by emulsion polymerization, which was initiated by glow discharge electrolysis plasma (GDEP). The effects of discharge voltage, discharge time, monomer ratio and the amounts of cross-linking agent were examined and discussed in detail. The chemical structure of the obtained resin was characterized by means of attenuated total reflectance Fourier transform infrared spectroscopy, thermogravimetric analysis, and scanning electron microscopy. The optimal conditions were obtained as: discharge voltage was 600 V, discharge time was 8 min, the ratios of BMA:BA being 2:1 for chloroform and 3:1 for xylene, with 2% N, N'-methylenebis. Under optimal conditions, the oil absorbency was 70 g/g for chloroform and 46 g/g for xylene. Moreover, the absorptive dynamical behavior of the resulting resin was also investigated

Bulk-loaded emulsion explosives technology

Energy Technology Data Exchange (ETDEWEB)

Borg, D.G. [Blasting Analysis International, Inc., Allentown, PA (United States)

1995-01-01

The largest use of emulsion explosives and emulsion-Anfo blends is in surface mining operations. An emulsion explosive is a two-phase system: the inner phase is madeup of an oxidizer solution; the outer phase is made up of oils or an oil/wax blend. Emulsion Anfo blends have been used to expand drill patterns, increase fragmentation, and provide extra energy for blast casting. 3 tabs.

Ultrasonic velocities, densities, and excess molar volumes of binary mixtures of N,N-dimethyl formamide with methyl acrylate, or ethyl acrylate, or butyl acrylate, or 2-ethyl hexyl acrylate at T = 308.15 K

Energy Technology Data Exchange (ETDEWEB)

Kondaiah, M. [Department of Physics, Acharya Nagarjuna University, Nagarjuna Nagar 522510, Andhra Pradesh (India); Sravana Kumar, D. [Dr. V.S. Krishna Govt. Degree College, Visakhapatnam, Andhra Pradesh (India); Sreekanth, K. [Department of Physics, Acharya Nagarjuna University, Nagarjuna Nagar 522510, Andhra Pradesh (India); Krishna Rao, D., E-mail: krdhanekula@yahoo.co.in [Department of Physics, Acharya Nagarjuna University, Nagarjuna Nagar 522510, Andhra Pradesh (India)

2011-12-15

Highlights: > Positive values of V{sub m}{sup E}, indicate dispersion forces between acrylic esters and DMF. > V{sub m}{sup E} values compared with Redlich-Kister polynomial. > Partial molar volumes data conclude that weak interactions exist in the systems. > Measured velocity values compared with theoretical values obtained by polynomials. - Abstract: Ultrasonic velocities, u, densities, {rho}, of binary mixtures of N,N-dimethyl formamide (DMF) with methyl acrylate (MA), ethyl acrylate (EA), butyl acrylate (BA), and 2-ethyl hexyl acrylate (EHA), including pure liquids, over the entire composition range have been measured at T = 308.15 K. Using the experimental results, the excess molar volume, V{sub m}{sup E}, partial molar volumes, V-bar {sub m,1}, V-bar{sub m,2}, and excess partial molar volumes, V-bar{sub m,1}{sup E}, V-bar{sub m,2}{sup E} have been calculated. Molecular interactions in the systems have been studied in the light of variation of excess values of calculated properties. The excess properties have been fitted to Redlich-Kister type polynomial and the corresponding standard deviations have been calculated. The positive values of V{sub m}{sup E} indicate the presence of dispersion forces between the DMF and acrylic ester molecules. Further theoretical values of sound velocity in the mixtures have been evaluated using various theories and have been compared with experimental sound velocities to verify the applicability of such theories to the systems studied. Theoretical ultrasonic velocity data have been used to study molecular interactions in the binary systems investigated.

Emulsion Science Basic Principles

CERN Document Server

Leal-Calderon, Fernando; Schmitt, Véronique

2007-01-01

Emulsions are generally made out of two immiscible fluids like oil and water, one being dispersed in the second in the presence of surface-active compounds.They are used as intermediate or end products in a huge range of areas including the food, chemical, cosmetic, pharmaceutical, paint, and coating industries. Besides the broad domain of technological interest, emulsions are raising a variety of fundamental questions at the frontier between physics and chemistry. This book aims to give an overview of the most recent advances in emulsion science. The basic principles, covering aspects of emulsions from their preparation to their destruction, are presented in close relation to both the fundamental physics and the applications of these materials. The book is intended to help scientists and engineers in formulating new materials by giving them the basics of emulsion science.

Reduced Fat Food Emulsions: Physicochemical, Sensory, and Biological Aspects.

Science.gov (United States)

Chung, Cheryl; Smith, Gordon; Degner, Brian; McClements, David Julian

2016-01-01

Fat plays multiple important roles in imparting desirable sensory attributes to emulsion-based food products, such as sauces, dressings, soups, beverages, and desserts. However, there is concern that over consumption of fats leads to increased incidences of chronic diseases, such as obesity, coronary heart disease, and diabetes. Consequently, there is a need to develop reduced fat products with desirable sensory profiles that match those of their full-fat counterparts. The successful design of high quality reduced-fat products requires an understanding of the many roles that fat plays in determining the sensory attributes of food emulsions, and of appropriate strategies to replace some or all of these attributes. This paper reviews our current understanding of the influence of fat on the physicochemical and physiological attributes of food emulsions, and highlights some of the main approaches that can be used to create high quality emulsion-based food products with reduced fat contents.

Effect of surface treatments on the bond strength of soft denture lining materials to an acrylic resin denture base.

Science.gov (United States)

Gundogdu, Mustafa; Yesil Duymus, Zeynep; Alkurt, Murat

2014-10-01

Adhesive failure between acrylic resin and resilient liner material is commonly encountered in clinical practice. The purpose of this study was to evaluate the effect of different surface treatments on the bond strength of 2 different resilient lining materials to an acrylic resin denture base. Ninety-six dumbbell-shaped specimens were fabricated from heat-polymerized acrylic resin, and 3 mm of the material was cut from the thin midsection. The specimens were divided into 6 groups according to their surface treatments: no surface treatment (control group), 36% phosphoric acid etching (acid group), erbium:yttrium-aluminum-garnet (Er:YAG) laser (laser group), airborne-particle abrasion with 50-μm Al2O3 particles (abrasion group), an acid+laser group, and an abrasion+laser group. The specimens in each group were divided into 2 subgroups according to the resilient lining material used: heat-polymerized silicone based resilient liner (Molloplast B) and autopolymerized silicone-based resilient liner (Ufi Gel P). After all of the specimens had been polymerized, they were stored in distilled water at 37°C for 1 week. A tensile bond strength test was then performed. Data were analyzed with a 2-way ANOVA, and the Sidak multiple comparison test was used to identify significant differences (α=.05). The effects of the surface treatments and resilient lining materials on the surface of the denture base resin were examined with scanning electron microscopy. The tensile bond strength was significantly different between Molloplast B and Ufi Gel P (P<.001). The specimens of the acid group had the highest tensile bond strength, whereas those of the abrasion group had the lowest tensile bond strength. The scanning electron microscopy observations showed that the application of surface treatments modified the surface of the denture base resin. Molloplast B exhibited significantly higher bond strength than Ufi Gel P. Altering the surface of the acrylic resin denture base with 36

Scintillation properties of acrylate based plastic scintillator by photoploymerization method

Energy Technology Data Exchange (ETDEWEB)

Kim, Sung Hwan [Dept. of Radiological Science, Cheongju University, Cheongju (Korea, Republic of); Lee, Joo Il [Dept. of of Radiology, Daegu Health College, Daegu (Korea, Republic of)

2016-12-15

In this study, we prepared and characterized a acrylate based UV-curable plastic scintillator. It was used co-polymers TMPTA, DHPA and Ultima GoldTM LLT organic scintillator. The emission spectrum of the plastic scintillator was located in the range of 380⁓520 nm, peaking at 423 nm. And the scintillator is more than 50% transparent in the range of 400⁓ 800 nm. The emission spectrum is well match to the quantum efficiency of photo-multiplier tube and the fast decay time of the scintillation is 12 ns, approximately. This scintillation material provides the possibility of combining 3D printing technology, and then the applications of the plastic scintillator may be expected in human dosimetry etc.

Preparation and Application of Water-in-Oil Emulsions Stabilized by Modified Graphene Oxide

Directory of Open Access Journals (Sweden)

Xiaoma Fei

2016-08-01

Full Text Available A series of alkyl chain modified graphene oxides (AmGO with different alkyl chain length and content was fabricated using a reducing reaction between graphene oxide (GO and alkyl amine. Then AmGO was used as a graphene-based particle emulsifier to stabilize Pickering emulsion. Compared with the emulsion stabilized by GO, which was oil-in-water type, all the emulsions stabilized by AmGO were water-in-oil type. The effects of alkyl chain length and alkyl chain content on the emulsion properties of AmGO were investigated. The emulsions stabilized by AmGO showed good stability within a wide range of pH (from pH = 1 to pH = 13 and salt concentrations (from 0.1 to 1000 mM. In addition, the application of water-in-oil emulsions stabilized by AmGO was investigated. AmGO/polyaniline nanocomposite (AmGO/PANi was prepared through an emulsion approach, and its supercapacitor performance was investigated. This research broadens the application of AmGO as a water-in-oil type emulsion stabilizer and in preparing graphene-based functional materials.

Radiation-initiated emulsion copolymerization of styrene and carboxylic acid monomers

International Nuclear Information System (INIS)

Egusa, S.; Makuuchi, K.

1982-01-01

The emulsion copolymerization of styrene and carboxylic acid monomers such as acrylic, methacrylic, and itaconic acids (AAc, MAAc, IAc) was studied by using 60 Co γ-rays as initiator and sodium dodecylsulfate as emulsifier. The polymerization behavior of these acid monomers was followed by simultaneous conductometric and potentiometric titrations for a latex sample taken in polymerization. The polymerization rate of these acid monomers increases in the following order of hydrophobicity: IAc < AAc < MAAc; this suggests that their polymerization sites are mainly the surface and/or subsurface regions of latex particles. The copolymerization rate of styrene and acid monomer increases with an increase in the acid monomer content for AAc and MAAc, whereas for IAc the rate decreases. The particle sizes determined by the stopped-flow method reveal that this variation of copolymerization rate cannot be explained by the number of growing particles and should be attributed to another factor; for instance, the transfer rate of styrene molecules from oil droplets to growing particles

Water-base acrylic terpolymer as a corrosion inhibitor for SAE1018 in simulated sour petroleum solution in stagnant and hydrodynamic conditions

International Nuclear Information System (INIS)

Vakili Azghandi, M.; Davoodi, A.; Farzi, G.A.; Kosari, A.

2012-01-01

Highlights: ► Corrosion inhibition of a water-base copolymer, ATP, was studied. ► Efficiency more than 90% was obtained with 0.8 mmol/L ATP in 2000 rpm. ► ATP obeys Langmuir isotherm in static and hydrodynamic conditions. ► With the presence of ATP, OM images showed a decrease in surface attack. - Abstract: The effect of static and hydrodynamic conditions (0–2000 rpm) on corrosion inhibition of a water-base acrylic terpolymer (ATP), methyl methacrylate/butyl acrylate/acrylic acid, for SAE1018 steel in simulated sour petroleum corrosive solution (NACE 1D196) were investigated by AC/DC electrochemical tests. Increase in rotation speed accelerates the corrosion rate; however the corrosion inhibitor efficiency increases. This was attributed to the enhanced mass transport of inhibitor molecules to the metal surface. OM examinations also demonstrate that in presence of ATP, a decrease in corrosion attacks is observed. Thermodynamic calculations also showed that ATP obeys Langmuir adsorption isotherm and adsorbs chemically into the surface.

Emulsion characteristics, chemical and textural properties of meat systems produced with double emulsions as beef fat replacers.

Science.gov (United States)

Serdaroğlu, Meltem; Öztürk, Burcu; Urgu, Müge

2016-07-01

In recent years, double emulsions are stated to have a promising potential in low-fat food production, however, there are very few studies on their possible applications in meat matrices. We aimed to investigate the quality of beef emulsion systems in which beef fat was totally replaced by double emulsions (W1/O/W2) prepared with olive oil and sodium caseinate (SC) by two-step emulsification procedure. Incorporation of W1/O/W2 emulsion resulted in reduced lipid, increased protein content, and modified fatty acid composition. W1/O/W2 emulsion treatments had lower jelly and fat separation, higher water-holding capacity and higher emulsion stability than control samples with beef fat. Increased concentrations of W1/O/W2 emulsions resulted in significant changes in texture parameters. TBA values were lower in W1/O/W2 emulsion treatments than control treatment after 60days of storage. In conclusion, our study confirms that double emulsions had promising impacts on modifying fatty acid composition and developing both technologically and oxidatively stable beef emulsion systems. Copyright © 2016 Elsevier Ltd. All rights reserved.

Asphalt emulsion; Asphalt nyuzai ni tsuite

Energy Technology Data Exchange (ETDEWEB)

Suzuki, T. [Toa Doro Kogyo Co. Ltd., Tokyo (Japan)

1994-12-28

The emulsification, manufacture, type, applications, etc. of asphalt emulsion were introduced. The emulsification of asphalt is obtained by mixing heated asphalt into an emulsification liquid where emulsifier is added to water and then agitating it. The emulsifier has both hydrophilic and lipophilic parts in the same molecule, prevents collision between asphalt particles after being arranged properly on the surface of asphalt particles, and prevent separation into water and asphalt. The emulsion is available for penetration and for mixing depending on applications and can be classified into cation emulsion, anion emulsion, and nonionic emulsion according to the property. The emulsion is mainly applied to road pavement, reaching approximately 90 % of the total manufactured emulsion. It is also used for other areas such as the filler of a slab race of each bullet train of Sanyo, Tohoku, and Jyoetsu and is also applied to the formation of a water-proof layer by spraying a high-concentration emulsion with rubber, agricultural water channels using asphalt emulsion and nonwoven cloth, etc. in civil engineering and agricultural fields. 2 refs., 13 figs., 8 tabs.

Large Acrylic Spherical Windows In Hyperbaric Underwater Photography

Science.gov (United States)

Lones, Joe J.; Stachiw, Jerry D.

1983-10-01

Both acrylic plastic and glass are common materials for hyperbaric optical windows. Although glass continues to be used occasionally for small windows, virtually all large viewports are made of acrylic. It is easy to uderstand the wide use of acrylic when comparing design properties of this plastic with those of glass, and glass windows are relatively more difficult to fabricate and use. in addition there are published guides for the design and fabrication of acrylic windows to be used in the hyperbaric environment of hydrospace. Although these procedures for fabricating the acrylic windows are somewhat involved, the results are extremely reliable. Acrylic viewports are now fabricated to very large sizes for manned observation or optical quality instrumen tation as illustrated by the numerous acrylic submersible vehicle hulls for hu, an occupancy currently in operation and a 3600 large optical window recently developed for the Walt Disney Circle Vision under-water camera housing.

Dynamically formed hydrous zirconium (IV) oxide-polyelectrolyte membranes. III: Poly(acrylic acid) and substituted poly(acrylic acid) homo, co and terpolymer membranes

International Nuclear Information System (INIS)

Van Reenen, A.J.; Sanderson, R.D.

1989-01-01

A series of acrylic acid and substituted acrylic acid homo, co and terpolymers was synthesised. These polymers were used as polyelectrolytes in dynamically formed hydrous zirconium (iv) oxide-polyelectrolyte membranes. Substitution of the acrylic acid α-hydrogen was done to increase the number of carboxylic acid groups per monomer unit and to change the acid strength of acrylic acid carboxylic acid group. None of these changes improved the salt rejection of these membranes over that of commercially used poly(acrylic acid). Improvement in rejection was found when a hydrophobic comonomer, vinyl acetate, was used in conjunction with acrylic acid in a copolymer dynamic membrane. 16 refs., 6 figs., 1 tab

ZETA POTENTIAL AND COLOR INVESTIGATIONS OF VEGETABLE OIL BASED EMULSIONS AS ECO-FRIENDLY LUBRICANTS

Directory of Open Access Journals (Sweden)

ROMICĂ CREŢU

2017-06-01

Full Text Available In the past 10 years, the need for biodegradable lubricants has been more and more emphasized. The use of vegetable oils as lubricants offers several advantages. The vegetable oils are biodegradable; thus, the environmental pollution is minimal either during or after their use. The aim of this paper is to presents a preliminary study concerning the influence of some preparation conditions on the stability of vegetable oil-in-water (O/W emulsions as eco-friendly lubricants stabilized by nonionic surfactant. In this context, vegetable oil-in-water emulsions characteristics where assessed using microscopically observation and zeta potential. In addition, the color of these emulsions can be evaluated. It can be observed that the emulsions tend to stabilize in time.

Relationships Between Base-Catalyzed Hydrolysis Rates or Glutathione Reactivity for Acrylates and Methacrylates and Their NMR Spectra or Heat of Formation

Directory of Open Access Journals (Sweden)

Yoshinori Kadoma

2012-05-01

Full Text Available The NMR chemical shift, i.e., the π-electron density of the double bond, of acrylates and methacrylates is related to the reactivity of their monomers. We investigated quantitative structure-property relationships (QSPRs between the base-catalyzed hydrolysis rate constants (k1 or the rate constant with glutathione (GSH (log k_GSH for acrylates and methacrylates and the ¹³C NMR chemical shifts of their α,β-unsaturated carbonyl groups (δC_α and δC_β or heat of formation (Hf calculated by the semi-empirical MO method. Reported data for the independent variables were employed. A significant linear relationship between k1 and δC_β, but not δC_α, was obtained for methacrylates (r² = 0.93, but not for acrylates. Also, a significant relationship between k1 and Hf was obtained for both acrylates and methacrylates (r² = 0.89. By contrast, log k_GSH for acrylates and methacrylates was linearly related to their δC_β (r² = 0.99, but not to Hf. These findings indicate that the ¹³C NMR chemical shifts and calculated Hf values for acrylates and methacrylates could be valuable for estimating the hydrolysis rate constants and GSH reactivity of these compounds. Also, these data for monomers may be an important tool for examining mechanisms of reactivity.

Interactions between Therapeutic Proteins and Acrylic Acid Leachable.

Science.gov (United States)

Liu, Dengfeng; Nashed-Samuel, Yasser; Bondarenko, Pavel V; Brems, David N; Ren, Da

2012-01-01

Leachables are chemical compounds that migrate from manufacturing equipment, primary containers and closure systems, and packaging components into biopharmaceutical and pharmaceutical products. Acrylic acid (at concentration around 5 μg/mL) was detected as leachable in syringes from one of the potential vendors (X syringes). In order to evaluate the potential impact of acrylic acid on therapeutic proteins, an IgG 2 molecule was filled into a sterilized X syringe and then incubated at 45 °C for 45 days in a pH 5 acetate buffer. We discovered that acrylic acid can interact with proteins at three different sites: (1) the lysine side chain, (2) the N-terminus, and (3) the histidine side chain, by the Michael reaction. In this report, the direct interactions between acrylic acid leachable and a biopharmaceutical product were demonstrated and the reaction mechanism was proposed. Even thought a small amount (from 0.02% to 0.3%) of protein was found to be modified by acrylic acid, the modified protein can potentially be harmful due to the toxicity of acrylic acid. After being modified by acrylic acid, the properties of the therapeutic protein may change due to charge and hydrophobicity variations. Acrylic acid was detected to migrate from syringes (Vendor X) into a therapeutic protein solution (at a concentration around 5 μg/mL). In this study, we discovered that acrylic acid can modify proteins at three different sites: (1) the lysine side chain, 2) the N-terminus, and 3) the histidine side chain, by the Michael reaction. In this report, the direct interactions between acrylic acid leachable and a biopharmaceutical product were demonstrated and the reaction mechanism was proposed.

Physical Stability of Whippable Oil-in-Water Emulsions

DEFF Research Database (Denmark)

Munk, Merete Bøgelund

Whippable emulsions based on vegetable fat are increasingly used as replacement for dairy whipping creams. One of the quality criteria of whippable emulsions is that it should be low-viscous prior to whipping, but sudden viscosity increase or even solidification during storage and transport...... the impact of ingredient composition, with focus on low-molecular-weight (LMW) emulsifiers. Three monoglyceride-based LMW-emulsifiers were selected: Lactic acid ester of saturated monoglyceride (LACTEM), unsaturated monoglyceride (GMU), and saturated monoglyceride (GMS). LMW-emulsifiers had major impact...

Durability of base courses with mineral-cement-emulsion mixes (MCEM)

Science.gov (United States)

Kukiełka, J.; Sybilski, D.

2018-05-01

Base courses with mineral-cement-emulsion mixes (MCEM) have been the subject of research, surveys and development of e.g. new requirements included in the Guidelines of 2014 [15]. In this paper the results of sample test and survey of road sections, assessment of transverse cracks and load-bearing capacity with FWD after 13 years of exploitation are presented. On the MCEM samples the following tests were carried out: resilient modulus using NAT, complex stiffness modulus (E*), phase shift angle at various temperatures and loading frequencies thereby obtaining master curves, fatigue life and low-temperature resistance by identifying the tensile stress restrained (TSRST) which allowed for general assessment of constructed base courses.

Comparison of the Retinal Straylight in Pseudophakic Eyes with PMMA, Hydrophobic Acrylic, and Hydrophilic Acrylic Spherical Intraocular Lens

Directory of Open Access Journals (Sweden)

Ya-wen Guo

2014-01-01

Full Text Available Purpose. To investigate the intraocular straylight value after cataract surgery. Methods. In this study, 76 eyes from 62 patients were subdivided into three groups. A hydrophobic acrylic, a hydrophilic acrylic, and a PMMA IOL were respectively, implanted in 24 eyes, 28 eyes, and 24 eyes. Straylight was measured using C-Quant at 1 week and 1 month postoperatively in natural and dilated pupils. Results. The hydrophilic acrylic IOLs showed significantly lower straylight values than those of the hydrophobic acrylic IOLs in dilated pupils at 1 week and 1 month after surgery (P0.05. Moreover, no significant difference was found in straylight between natural and dilated pupils in each group at 1 week and 1 month postoperatively (P>0.05. Conclusions. Although the hydrophobic acrylic IOL induced more intraocular straylight, straylight differences among the 3 IOLs were minimal. Pupil size showed no effect on intraocular straylight; the intraocular straylight was stable 1 week after surgery.

40 CFR 721.324 - Alkoxylated acrylate polymer (generic).

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Alkoxylated acrylate polymer (generic... Substances § 721.324 Alkoxylated acrylate polymer (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as alkoxylated acrylate polymer...

Molecular and functional assessment of multicellular cancer spheroids produced in double emulsions enabled by efficient airway resistance based selective surface treatment

Science.gov (United States)

Ma, Xiao; Leth Jepsen, Morten; Ivarsen, Anne Kathrine R.; Knudsen, Birgitta R.; Ho, Yi-Ping

2017-09-01

Multicellular spheroids have garnered significant attention as an in vitro three-dimensional cancer model which can mimick the in vivo microenvironmental features. While microfluidics generated double emulsions have become a potential method to generate spheroids, challenges remain on the tedious procedures. Enabled by a novel ‘airway resistance’ based selective surface treatment, this study presents an easy and facile generation of double emulsions for the initiation and cultivation of multicellular spheroids in a scaffold-free format. Combining with our previously developed DNA nanosensors, intestinal spheroids produced in the double emulsions have shown an elevated activities of an essential DNA modifying enzyme, the topoisomerase I. The observed molecular and functional characteristics of spheroids produced in double emulsions are similar to the counterparts produced by the commercially available ultra-low attachment plates. However, the double emulsions excel for their improved uniformity, and the consistency of the results obtained by subsequent analysis of the spheroids. The presented technique is expected to ease the burden of producing spheroids and to promote the spheroids model for cancer or stem cell study.

The effect of submersion denture base acrylic resin in a betel leaf ekstract solution against growth Candida albicans

Directory of Open Access Journals (Sweden)

Andi Izham

2016-06-01

Full Text Available Denture base is a protesa which replace some or all of the lost original teeth and surrounding tissues. The Pupose of making protesa is for restore the function, appearance, comfort and impaired health result lost teeth. One part of the denture base is base plate. Microorganisms are often found in the oral cavity is Candida albicans (C.albicans approximately 40% in the oral cavity.C.albicans can penetrate the acrylic resin that can infect the soft tissue and is the cause of denture stomatitis therefore the disinfection of denture base is a important factor that must be done. In general betel leaves contant up to 4.2% essential oil compounds and phenyl propanoid and tannin. These compounds is a antimicroba and antifungal which can inhibit the growth of several type of bacteria among others Escherichia coli, Salmonella sp, Staphylococcus aurens, Klebstella, Pasteurella and can turn off the C.albicans. The purpose of the research is to determine how the effect of submersion denture base acrylic resin in a betel leaf ekstract solution against growth C.albicans.Type of research is an experimental laboratory with a longitudinal design (follow-up study. The sampling method used is total sampling. The results showed that the number of C.albicans colonies n denture base acrylic resin which soaked betel leaf extract solution that the dilution 10-1  with consentration 2.5% total colony count is 2 and the results 2.0 x 101 CFU/ml, on a control solution that the dilution 10-2 total colony 355 and the result 3.55 x 104 CFU/ml, that the dilution  10-3 total colony 62 and the result 6.2 x 104 CFU/ml.

Synthesis of butyl acrylate-styrene block copolymers in emulsion by reversible addition-fragmentation chain transfer : effect of surfactant migration upon film formation

NARCIS (Netherlands)

Monteiro, M.J.; Sjöberg, M.; Göttgens, C.M.; Vlist, van der J.

2000-01-01

The synthesis of block copolymers in an environmentally friendly medium was carried out in emulsion polymerizations through the reversible addition-fragmentation chain transfer process, using a transfer active xanthate (MADIX) agent, under batch and starved-feed conditions. First, ab initio

Polyurethane-acrylate-based hydrophobic film: Facile fabrication, characterization, and application

Science.gov (United States)

Park, Jongsung; Nguyen, Bui Quoc Huy; Kim, Ji-Kwan; Shanmugasundaram, Arunkumar; Lee, Dong-Weon

2018-06-01

Polyurethane-acrylate (PUA) is a versatile UV-curable polymer with a short curing time at room temperature, whose surface structure can be flexibly modified by applying various micropatterns. In this paper, we propose a facile and cost-effective fabrication method for the continuous production of an optically transparent PUA-based superhydrophobic thin film. Poly(dimethylsiloxane) (PDMS) was employed as a soft mold for the fabrication of PUA films through the roll-to-roll technique. In addition, nanosilica was spray-coated onto the PUA surface to further improve the hydrophobicity. The fabricated PUA thin film showed the highest static water contact angle (WCA) of ∼140°. The high durability of the PUA film was also demonstrated through mechanical impacting tests. Furthermore, only ∼2% of voltage loss was observed in the solar panel covered with the PUA-based superhydrophobic film. These obtained results indicate the feasibility of applying the film as a protective layer in applications requiring a high transparency and a self-cleaning effect.

Optimization of cellulose acrylate and grafted 4-vinylpyridine and 1-vinylimidazole synthesis

Directory of Open Access Journals (Sweden)

Bojanić Vaso

2010-01-01

Full Text Available Optimization of cellulose acrylate synthesis by reaction with sodium cellulosate and acryloyl chloride was carried out. Optimal conditions for conducting the synthesis reaction of cellulose acrylate were as follows: the molar ratio of cellulose/potassium-t-butoxide/acryloyl chloride was 1:3:10 and the optimal reaction time was 10 h. On the basis of elemental analysis with optimal conditions for conducting the reaction of cellulose acrylate, the percentage of substitution of glucose units in cellulose Y = 80.7%, and the degree of substitution of cellulose acrylate DS = 2.4 was determined. The grafting reaction of acrylate vinyl monomers onto cellulose in acetonitrile with initiator azoisobutyronitrile (AIBN in a nitrogen atmosphere was performed, by mixing for 5 h at acetonitrile boiling temperature. Radical copolymerization of synthesized cellulose acrylate and 4-vinylpyridine, 1-vinylimidazole, 1-vinyl-2-pyrrolidinone and 9-vinylcarbazole, cellulose-poly-4-vinylpyridine (Cell-PVP, cellulose-poly-1- vinylimidazole (Cell-PVIm and cellulose-poly-1-vinyl-2-pyrrolidinone (Cell-P1V2P and cellulose-poly-9-vinylcarbazole (Cell-P9VK were synthesized. Acrylate cellulose and cellulose grafted copolymers were confirmed by IR spectroscopy, based on elementary analysis and the characteristics of grafted copolymers of cellulose were determined. The mass share of grafted copolymers, X, the relationship of derivative parts/cellulose vinyl group, Z, and the degree of grafting copolymers of cellulose (mass% were determined. In reaction of methyl iodide and cellulose-poly-4-vinylpyridine (Cell-PVP the cellulose-1-methyl-poly-4-vinylpyridine iodide (Cell-1-Me-PVPJ was synthesized. Cellulose acrylate and grafted copolymers were obtained with better thermal, electrochemical and ion-emulation properties for bonding of noble metals Au, Pt, Pd from water solutions. The synthesis optimization of cellulose acrylate was applied as a model for the synthesis of grafted

Radiation dosimetry and spectrometry with superheated emulsions

International Nuclear Information System (INIS)

D'Errico, Francesco

2001-01-01

Detectors based on emulsions of overexpanded halocarbon droplets in tissue equivalent aqueous gels or soft polymers, known as 'superheated drop detectors' or 'bubble (damage) detectors', have been used in radiation detection, dosimetry and spectrometry for over two decades. Recent technological advances have led to the introduction of several instruments for individual and area monitoring: passive integrating meters based on the optical or volumetric registration of the bubbles, and active counters detecting bubble nucleations acoustically. These advances in the instrumentation have been matched by the progress made in the production of stable and well-specified emulsions of superheated droplets. A variety of halocarbons are employed in the formulation of the detectors, and this permits a wide range of applications. In particular, halocarbons with a moderate degree of superheat, i.e. a relatively small difference between their operating temperature and boiling point, can be used in neutron dosimetry and spectrometry since they are only nucleated by energetic heavy ions such as those produced by fast neutrons. More recently, halocarbons with an elevated degree of superheat have been utilised to produce emulsions that nucleate with much smaller energy deposition and detect low linear energy transfer radiations, such as photons and electrons. This paper reviews the detector physics of superheated emulsions and their applications in radiation measurements, particularly in neutron dosimetry and spectrometry

21 CFR 177.1320 - Ethylene-ethyl acrylate copolymers.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ethylene-ethyl acrylate copolymers. 177.1320... Basic Components of Single and Repeated Use Food Contact Surfaces § 177.1320 Ethylene-ethyl acrylate copolymers. Ethylene-ethyl acrylate copolymers may be safely used to produce packaging materials, containers...

Iron-mediated lipid oxidation in 70% fish oil-in-ater emulsions

DEFF Research Database (Denmark)

Horn, Anna Frisenfeldt; Nielsen, Nina Skall; Jacobsen, Charlotte

2012-01-01

The objective of this study was to investigate the protective effect of five different emulsifiers on iron‐mediated lipid oxidation in 70% fish oil‐in‐water emulsions. The emulsifiers were either based on protein (whey protein isolate and sodium caseinate) or based on phospholipid (soy lecithin...... and two milk phospholipids with different phospholipid contents, MPL20 and MPL75). Lipid oxidation was studied at pH 4.5 and 7.0, and results were compared to lipid oxidation in neat fish oil. Results showed that all emulsions oxidised more than neat oil. Furthermore, emulsions prepared with proteins...

A novel and efficient water-based composite binder for LiCoO{sub 2} cathodes in lithium-ion batteries

Energy Technology Data Exchange (ETDEWEB)

Chu, Yung-Ju [Department of Materials and Mineral Resources Engineering, National Taipei University of Technology, Taipei (China); Peng, Xing-Wei [Institute of Materials Science and Engineering, National Taipei University of Technology, Taipei (China); Wang, Fu-Ming; Yang, Chang-Rung [Material and Chemical Research Laboratories, Industrial Technology Research Institute, Chutung, Hsinchu (China); Li, Chia-Chen [Department of Materials and Mineral Resources Engineering, National Taipei University of Technology, Taipei (China); Institute of Materials Science and Engineering, National Taipei University of Technology, Taipei (China); Lee, Jyh-Tsung

2007-11-15

The dispersion, adhesion strength, electrical, and electrochemical properties of LiCoO{sub 2} cathodes in lithium-ion batteries with the addition of a new composite binder composed of two acrylic emulsions, poly(butyl acrylate)-based (PBA) and polyacrylonitrile-based (PA) latex in a ratio of 3:7, were evaluated. PBA binder has a low-glass transition temperature of 10 C, which can improve the flexibility of the electrode. This new composite binder has a very good binding ability as same as the typical organic solvent-based binder, poly(vinylidene fluoride). The dispersions of the water-based cathode slurries with the composite binder were measured by analyzing the viscosity and sedimentation behaviors. The results show that the new composite binder can well disperse the LiCoO{sub 2}. Moreover, using the new composite binder could greatly improve the rate capabilities and the cycle stability of water-based LiCoO{sub 2} cathodes. (author)

Study of Some Technical Problems in Nuclear Emulsions

International Nuclear Information System (INIS)

Tarrega Tornero, M. P.

1967-01-01

A methodological study of various technical aspects of photographic emulsions is presented. This study enables the emulsion method to be used in certain physical problems, and can be summarized under the following headings. 1) Variation of different ionization indices with the degree of development. A measure of the degree of development is introduced. This measure called the α -mark, is based on the average width of tracks due to α-particles. Using the α-mack the influence of several factors such as the duration, temperature and concentration of the developing liquid are investigated. A comparative study of the sensitivity of llford C 2 and K 2 emulsions is given. (Author) 9 refs

21 CFR 177.1310 - Ethylene-acrylic acid copolymers.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ethylene-acrylic acid copolymers. 177.1310 Section... Basic Components of Single and Repeated Use Food Contact Surfaces § 177.1310 Ethylene-acrylic acid copolymers. The ethylene-acrylic acid copolymers identified in paragraph (a) of this section may be safely...

Radiation-induced grafting of acrylic acid onto polypropylene film and its biodegradability

Science.gov (United States)

Mandal, Dev K.; Bhunia, Haripada; Bajpai, Pramod K.; Chaudhari, C. V.; Dubey, K. A.; Varshney, L.

2016-06-01

Polypropylene based commodity polyolefins are widely used in packaging, manufacturing, electrical, pharmaceutical and other applications. The aim of the present work is to study the effect of grafting of acrylic acid on the biodegradability of acrylic acid grafted polypropylene. The effect of different conditions showed that grafting percentage increased with increase in monomer concentration, radiation dose and inhibitor concentration but decreased with increase in radiation dose rate. The maximum grafting of 159.4% could be achieved at optimum conditions. The structure of grafted polypropylene films at different degree of grafting was characterized by EDS, FTIR, TGA, DSC, SEM and XRD. EDS studies showed that the increase in acrylic acid grafting percentage increased the hydrophilicity of the grafted films. FTIR studies indicated the presence of acrylic acid on the surface of polypropylene film. TGA studies revealed that thermal stability decreased with increase in grafting percentage. DSC studies showed that melting temperature and crystallinity of the grafted polypropylene films lower than polypropylene film. SEM studies indicated that increase in acrylic acid grafting percentage increased the wrinkles in the grafted films. The maximum biodegradability could be achieved to 6.85% for 90.5% grafting. This suggested that microorganisms present in the compost could biodegrade acrylic acid grafted polypropylene.

Effects of Novel Structure Bonding Materials on Properties of Aeronautical Acrylic

Directory of Open Access Journals (Sweden)

LI Zhisheng

2017-06-01

Full Text Available Novel structure bonding materials, J-351 epoxy adhesive film with low curing temperature and liquid modified acrylate SY-50s adhesive were chosen and characterized. The effects of adhesives on the mechanical properties of acrylic were studied. The results reveal that both adhesives have excellent bonding properties to acrylic. The stress-solvent crazing value of J-351 is higher than that of SY-50s. With the application of adhesive on the surface, mechanical properties of acrylic are declined. Casting acrylic shows more drastic decline than that of oriented acrylic. Through the characterization of fracture surface, we find that fracture of tensile sample derives from the side with adhesive. Mechanical properties of acrylic are more sensitive to SY-50s, because the liquid adhesive presents integrate bonding interface with acrylic. The interface between J-351 and acrylic is clear, making acrylic insensitive to J-351 film. Edge attachment strength of samples bonded with J-351 are higher than that of samples bonded with SY-50s due to the effects of adhesives on acrylic. J-351 epoxy adhesive film presents preferable application performance in the structure bonding of aeronautical acrylic.

A Novel Submicron Emulsion System Loaded with Doxorubicin Overcome Multi-Drug Resistance in MCF-7/ADR Cells.

Science.gov (United States)

Zhou, W P; Hua, H Y; Sun, P C; Zhao, Y X

2015-01-01

The purpose of the present study was to develop the Solutol HS15-based doxorubicin submicron emulsion with good stability and overcoming multi-drug resistance. In this study, we prepared doxorubicin submicron emulsion, and examined the stability after autoclaving, the in vitro cytotoxic activity, the intracellular accumulation and apoptpsis of doxorubicin submicron emulsion in MCF-7/ADR cells. The physicochemical properties of doxorubicin submicron emulsion were not significantly affected after autoclaving. The doxorubicin submicron emulsion significantly increased the intracellular accumulation of doxorubicin submicron emulsion and enhanced cytotoxic activity and apoptotic effects of doxorubicin. These results may be correlated to doxorubicin submicron emulsion inhibitory effects on efflux pumps through the progressive release of intracellular free Solutol HS15 from doxorubicin submicron emulsion. Furthermore, these in vitro results suggest that the Solutol HS15-based submicron emulsion may be a potentially useful drug delivery system to circumvent multi-drug resistance of tumor cells.

Emulsions from Aerosol Sprays

Science.gov (United States)

Hengelmolen; Vincent; Hassall

1997-12-01

An electrostatic emulsification apparatus has been designed for the purpose of studying diffusion from oil droplets which have a mean size in the range of approximately 1.5-3.5 &mgr;m, with standard deviations of 40-50%. The emulsification technique involves the collection of a spray of electrically charged oil droplets onto a rotating water film which is sustained from a reservoir. In this way, emulsions with volume fractions of approximately 10(-3) are produced within several minutes at oil flow rates of around 10(-2) ml min-1. Phase-Doppler anemometry (PDA) was used to assess droplet size distributions for the sprays and emulsions. Results show that the mean emulsion droplet size was smaller than the mean spray droplet size by several orders of magnitude. At flow rates around 10(-2) ml min-1, the spray droplet size distribution was little affected by the applied potential between about -4.20 and -4.65 kV (mean droplet size between approximately 7.6 and 7.8 &mgr;m, with standard deviations of approximately 20%), whereas the mean droplet size of the corresponding emulsion decreased more rapidly with applied potential. Above an applied potential of approximately -4.30 kV, which corresponded to an emulsion droplet size below approximately 2 &mgr;m, the measured volume fraction of the emulsion decreased with respect to the volume fraction as calculated on the basis of total amount of injected oil. Copyright 1997 Academic Press. Copyright 1997Academic Press

Chemoembolization of Neuroendocrine Liver Metastases Using Streptozocin and Tris-acryl Microspheres: Embozar (EMBOsphere + ZAnosaR) Study

Energy Technology Data Exchange (ETDEWEB)

Pelage, Jean-Pierre, E-mail: pelage-jp@chu-caen.fr; Fohlen, Audrey [Caen University and Medical Center, Department of Diagnostic Imaging and Interventional Radiology (France); Mitry, Emmanuel [Hopital Ambroise Pare, Department of Hepatogastroenterology and Oncology (France); Lagrange, Christine [Hopital Ambroise Pare, Department of Radiology (France); Beauchet, Alain [Hopital Ambroise Pare, Department of Biostatistics and Public Health (France); Rougier, Philippe [Hopital Ambroise Pare, Department of Hepatogastroenterology and Oncology (France)

2017-03-15

PurposeThe purpose of this prospective observational study was to evaluate the efficacy and tolerability of transarterial chemoembolization (TACE) for neuroendocrine liver metastases using a combination of streptozocin, Lipiodol, and tris-acryl microspheres.Patients and MethodsA total of 16 men and 9 women aged 59.6 ± 11.3 years, all with predominant liver disease, underwent 54 courses of TACE using an emulsion of 1.5 g of streptozocin and 10 ml of Lipiodol. Additional embolization was performed using 300–500 µm tris-acryl microspheres. Morphological response was evaluated using the RECIST criteria on multi-detector computed tomography or MRI. Clinical efficacy was evaluated particularly in patients with carcinoid syndrome.ResultsThe primary tumor was located in the small bowel or pancreas in 21 (84%) patients. Eleven (44%) patients presented with a carcinoid syndrome. Nineteen (76%) patients presented with more than 10 liver nodules. One delayed case of ischemic cholecystitis was treated conservatively. After a median follow-up of 36.1 months, 1 (4%) patient had a complete response, 12 (48%) patients had a partial response, and 7 (28%) patients had a stable disease corresponding to a disease control rate of 80%. All patients with carcinoid syndrome had significant improvement. Median time to progression was 18.8 months and overall survival was 100, 100, and 92% at 1, 2, and 3 years, respectively. Seven patients presented with extrahepatic progression with abdominal lymphadenopathies or metastases to the brain, ovary, adrenal gland, or lung.ConclusionOptimized TACE using a combination of streptozocin, Lipiodol, and tris-acryl microspheres is effective and well tolerated.

Kinetics of Crystallization in Polydisperse Emulsions.

Science.gov (United States)

Kashchiev; Kaneko; Sato

1998-12-01

The kinetics of isothermal crystallization of the droplets in polydisperse emulsions are analyzed under the condition that each emulsion droplet gives birth to one nucleus only. Expressions are derived for the time dependences of the number of crystallized droplets and the fraction of crystallized droplet volume in the cases of either volume or surface nucleation of the crystals in the droplets. The time for half-crystallization is determined as a function of the emulsion polydispersity, and it is found that the more polydisperse the emulsion, the shorter this time in comparison with that for the corresponding monodisperse emulsion. Formulae are also obtained for the change of the velocity Kv of propagation of ultrasound through polydisperse emulsions during the time t of isothermal crystallization of the droplets in them. Good agreement is found between theory and experiment in an analysis of available Kv(t) data for crystallization in polydisperse palm oil-in-water and n-hexadecane-in-water emulsions. The results obtained are directly applicable to devitrification and polymorphic transformation of disperse solid phases. Copyright 1998 Academic Press.

Electrochemically driven emulsion inversion

Science.gov (United States)

Johans, Christoffer; Kontturi, Kyösti

2007-09-01

It is shown that emulsions stabilized by ionic surfactants can be inverted by controlling the electrical potential across the oil-water interface. The potential dependent partitioning of sodium dodecyl sulfate (SDS) was studied by cyclic voltammetry at the 1,2-dichlorobenzene|water interface. In the emulsion the potential control was achieved by using a potential-determining salt. The inversion of a 1,2-dichlorobenzene-in-water (O/W) emulsion stabilized by SDS was followed by conductometry as a function of added tetrapropylammonium chloride. A sudden drop in conductivity was observed, indicating the change of the continuous phase from water to 1,2-dichlorobenzene, i.e. a water-in-1,2-dichlorobenzene emulsion was formed. The inversion potential is well in accordance with that predicted by the hydrophilic-lipophilic deviation if the interfacial potential is appropriately accounted for.

Direct Synthesis of Hyperbranched Poly(acrylic acid-co-3-hydroxypropionate

Directory of Open Access Journals (Sweden)

Efkan Çatıker

2015-01-01

Full Text Available Hyperbranched poly(acrylic acid-co-3-hydroxypropionate (PAcHP was synthesized by base-catalyzed hydrogen transfer polymerization of acrylic acid through one step. The copolymers obtained through solution and bulk polymerization were insoluble in water and all organic solvents tried. Structural and compositional characterizations of hyperbranched PAcHP were performed by using FTIR, solid 13C-NMR, TGA, and titrimetric analysis. Acrylate fraction of the hyperbranched PAcHP obtained via bulk polymerization was determined as 60–65% by comparing TGA curves of hyperbranched PAcHP and pure poly(3-hydroxy propionate (PHP. However, analytical titration of the same sample revealed that acrylic acid units were about 47.3%. The results obtained from TGA and analytical titration were used to evaluate the chemical structure of the copolymer. Hyperbranched PAcHP exhibited hydrogel properties. Swelling behavior of the copolymer was investigated at a wide pH range and ionic strength. The dynamic swelling profiles of hyperbranched PAcHP exhibited a fast swelling behavior in the first hour and achieved the equilibrium state within 12 h in PBS. Depending on the conditions, the copolymers exhibited swelling ratios up to 2100%. As the copolymer has easily biodegradable propionate and versatile functional acrylic acid units, it can be used as not only biodegradable material in medical applications but also raw material in personal care commodities.

Homogeneous synthesis of cellulose acrylate-g-poly (n-alkyl acrylate) solid-solid phase change materials via free radical polymerization.

Science.gov (United States)

Qian, Yong-Qiang; Han, Na; Bo, Yi-Wen; Tan, Lin-Li; Zhang, Long-Fei; Zhang, Xing-Xiang

2018-08-01

A novel solid-solid phase change materials, namely, cellulose acrylate-g-poly (n-alkyl acrylate) (CA-g-PAn) (n = 14, 16 and 18) were successfully synthesized by free radical polymerization in N, N-dimethylacetamide (DMAc). The successful grafting was confirmed by fourier transform infrared spectra (FT-IR) and nuclear magnetic resonance (NMR). The properties of the CA-g-PAn copolymers were investigated by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA). The phase change temperatures and the melting enthalpies of CA-g-PAn copolymers are in the range of 10.1-53.2 °C and 15-95 J/g, respectively. It can be adjusted by the contents of poly (n-alkyl acrylate) and the length of alkyl side-chain. The thermal resistant temperatures of CA-g-PA14, 16 and 18 copolymers are 308 °C, 292 °C and 273 °C, respectively. It show that all of grafting materials exhibit good thermal stability and shape stability. Therefore, it is expected to be applied in the cellulose-based thermos-regulating field. Copyright © 2018 Elsevier Ltd. All rights reserved.

Emulsion design for the delivery of β-carotene in complex food systems.

Science.gov (United States)

Mao, Like; Wang, Di; Liu, Fuguo; Gao, Yanxiang

2018-03-24

β-Carotene has been widely investigated both in the industry and academia, due to its unique bioactive attributes as an antioxidant and pro-vitamin A. Many attempts were made to design delivery systems for β-carotene to improve its dispersant state and chemical stability, and finally to enhance the functionality. Different types of oil-in-water emulsions were proved to be effective delivery systems for lipophilic bioactive ingredients, and intensive studies were performed on β-carotene emulsions in the last decade. Emulsions are thermodynamically unstable, and emulsions with intact structures are preferable in delivering β-carotene during processing and storage. β-Carotene in emulsions with smaller particle size has poor stability, and protein-type emulsifiers and additional antioxidants are effective in protecting β-carotene from degradation. Recent development in the design of protein-polyphenol conjugates has provided a novel approach to improve the stability of β-carotene emulsions. When β-carotene is consumed, its bioaccessibility is highly influenced by the digestion of lipids, and β-carotene in smaller oil droplets containing long-chain fatty acids has a higher bioaccessibility. In order to better deliver β-carotene in complex food products, some novel emulsions with tailor-made structures have been developed, e.g., multilayer emulsions, solid lipid particles, Pickering emulsions. This review summarizes the updated understanding of emulsion-based delivery systems for β-carotene, and how emulsions can be better designed to fulfill the benefits of β-carotene in functional foods.

Physical and mechanical properties of pressure-molded and injection-molded denture base acrylics in different conditions

Directory of Open Access Journals (Sweden)

Yousef A Shibat Al Hamd

2014-01-01

Conclusion: The three tested denture base acrylics did not show any significant differences in processing shrinkage. However, ProBase Hot showed significantly lower bending deflection values than Lucitone 199 and SR-Ivocap. Compared to Lucitone 199 and SR-Ivocap, ProBase Hot is a tougher and a stiffer material. Hence, it is more likely to fracture readily if subjected to extreme loading conditions due to the accidental fall of the denture on a hard surface or if the denture wearer inadvertently bites on a particularly hard particle.

A study on the effect of the concentration of N,N-methylenebisacrylamide and acrylic acid toward the properties of Dioscorea hispida-starch-based hydrogel

Science.gov (United States)

Ashri, Airul; Lazim, Azwan

2014-09-01

The research investigated the effects of acrylic acid (monomer) and N,N,-methylenebisacrylamide, MBA (crosslinker) toward the percentage of gel content, swelling ratio and ionic strength of a starch-based hydrogel. Starch grafted on poly (sodium acrylate), St-g-PAANa hydrogel was prepared by incorporating starch extracted from Dioscorea hispida in NaOH/aqueous solution using different composition of acrylic acid (AA) and N,N-methylenebisacrylamide (MBA) in the presence of potassium persulfate (KPS) as chemical initiator. The highest gel content was observed at 1:30 ratio of starch to AA and 0.10 M of MBA. Results showed the highest swelling ratio was observed at 1:15 ratio of starch to acrylic acid and 0.02 M of MBA solution. The same results also gave the highest swelling ratio for the ionic strength study. The FTIR analysis was also conducted in order to confirm the grafting of AA onto starch backbone.

Influence of processing parameters on morphology of polymethoxyflavone in emulsions.

Science.gov (United States)

Ting, Yuwen; Li, Colin C; Wang, Yin; Ho, Chi-Tang; Huang, Qingrong

2015-01-21

Polymethoxyflavones (PMFs) are groups of compounds isolated from citrus peels that have been documented with wide arrays of health-promoting bioactivities. Because of their hydrophobic structure and high melting point, crystallized PMFs usually have poor systemic bioavailability when consumed orally. To improve the oral efficiency of PMFs, a viscoelastic emulsion system was formulated. Because of the crystalline nature, the inclusion of PMFs into the emulsion system faces great challenges in having sufficient loading capacity and stabilities. In this study, the process of optimizing the quality of emulsion-based formulation intended for PMF oral delivery was systematically studied. With alteration of the PMF loading concentration, processing temperature, and pressure, the emulsion with the desired droplet and crystal size can be effectively fabricated. Moreover, storage temperatures significantly influenced the stability of the crystal-containing emulsion system. The results from this study are a good illustration of system optimization and serve as a great reference for future formulation design of other hydrophobic crystalline compounds.

Study on some characteristics of nuclear emulsions

Energy Technology Data Exchange (ETDEWEB)

Yonglian, Liu; Jinqin, Han; Huichang, Liu [Academia Sinica, Beijing, BJ (China). Inst. of Atomic Energy

1993-11-01

The authors describe the variation of some characteristics of the nuclear emulsion such as sensitivity, fog density and latent image stability influenced by adding ascorbic acid into the finished emulsion N-4. A comparative study of latent image stability is made between Fuji ET-7B nuclear emulsion and authors' under different temperature and relative humidity. The result indicates that the addition of ascorbic acid obviously improves the latent image stability of the emulsion N-4. The Fuji ET-7B emulsion and the emulsion N-4 containing ascorbic acid have similar latent image fading quality at lower temperature while the Japanese sample does have better quality at room temperature.

Effect of Microwave Cured Acrylic Resin on Candidal Growth in Complete denture

International Nuclear Information System (INIS)

Rasmy, A.H.M.

2009-01-01

This study was conducted to evaluate the effect of heat-cured acrylic resin denture base and microwave-cured acrylic resin denture base on Candidal growth. Seven completely edentulous male patients with no history of denture wearing participated in this study. All the selected patients were re-habilitated by mucosa supported complete dentures. The dentures were constructed from conventional heat-cured acrylic resin denture base following monoplane concept of occlusion. Before dismissing the patients and one month after denture insertion, salivary samples were collected according to oral rinse technique. One month resting period was allowed so as Candidal count can reach to normal. Then dentures were re based using microwave-cured acrylic denture base, before denture insertion and one month after denture insertion, salivary sample were collected before and one month following the same oral rinse technique. In the oral rinse technique, the patients were instructed to rinse their mouths with 10 mL of sterile phosphate buffered saline for 60 seconds. The rinse was then expectorated into a universal container and immediately transported to the laboratory for concentration by centrifugation, then cultured on sabouraud's dextrose agar plates which were incubated at 37 degree C for 48 hours. Microscopic examination and germ tube test were carried out for laboratory investigations. In addition, the morphological features of the isolated Candida from the samples tested in this study, were investigated using the scanning electron microscope(SEM)

Deep UV patterning of acrylic masters for molding biomimetic dry adhesives

International Nuclear Information System (INIS)

Sameoto, D; Menon, C

2010-01-01

We present a novel fabrication method for the production of biomimetic dry adhesives that allows enormous variation in fiber shapes and sizes. The technology is based on deep-UV patterning of commercial acrylic with semi-collimated light available from germicidal lamps, and combined careful processing conditions, material selection and novel developer choices to produce relatively high-aspect-ratio fibers with overhanging caps on large areas. These acrylic fibers are used as a master mold for subsequent silicone rubber negative mold casting. Because the bulk acrylic demonstrates little inherent adhesion to silicone rubbers, the master molds created in this process do not require any surface treatments to achieve high-yield demolding of interlocked structures. Multiple polymers can be cast from silicone rubber negative molds and this process could be used to structure smart materials on areas over multiple square feet. Using direct photopatterning of acrylic allows many of the desired structures for biomimetic dry adhesives to be produced with relative ease compared to silicon-based molding processes, including angled fibers and hierarchical structures. Optimized fiber shapes for a variety of polymers can be produced using this process, and adhesion measurements on a well-characterized polyurethane, ST-1060, are used to determine the effect of fiber geometry on adhesion performance

Effects of composition and layer thickness of a butyl acrylate/acrylic acid copolymer on the adhesion properties

Energy Technology Data Exchange (ETDEWEB)

Ghim, Deoukchen; Kim, Jung Hyeun [University of Seoul, Seoul (Korea, Republic of)

2016-02-15

Acrylic pressure-sensitive adhesives are synthesized by solution copolymerization using n-butyl acrylate and acrylic acid (AA) in ethyl acetate anhydrous. The copolymer composition is controlled for good adhesive properties by varying AA content. The monomer conversion is measured by the gravimetric method and FTIR technique. The adhesive layer thickness is measured by scanning electron microscopy, and the adhesive properties are evaluated with loop tack, 180 .deg. peel, and holding time measurements. The peel force increases with increasing the AA content up to 3 wt% and decreases at the AA content higher than 3 wt%, but the tack force decreases with increasing the AA content. The holding time increases with increasing the AA content, and it shows a similar trend with the T{sub g} of adhesives. The increase of layer thickness improves tack and peel forces, but it weakens the holding power. A tape thickness of about 20 μm shows well-balanced properties at 3 wt% AA content in the acrylic copolymer system.

Effects of composition and layer thickness of a butyl acrylate/acrylic acid copolymer on the adhesion properties

International Nuclear Information System (INIS)

Ghim, Deoukchen; Kim, Jung Hyeun

2016-01-01

Acrylic pressure-sensitive adhesives are synthesized by solution copolymerization using n-butyl acrylate and acrylic acid (AA) in ethyl acetate anhydrous. The copolymer composition is controlled for good adhesive properties by varying AA content. The monomer conversion is measured by the gravimetric method and FTIR technique. The adhesive layer thickness is measured by scanning electron microscopy, and the adhesive properties are evaluated with loop tack, 180 .deg. peel, and holding time measurements. The peel force increases with increasing the AA content up to 3 wt% and decreases at the AA content higher than 3 wt%, but the tack force decreases with increasing the AA content. The holding time increases with increasing the AA content, and it shows a similar trend with the T g of adhesives. The increase of layer thickness improves tack and peel forces, but it weakens the holding power. A tape thickness of about 20 μm shows well-balanced properties at 3 wt% AA content in the acrylic copolymer system.

Concanavalin-A conjugated fine-multiple emulsion loaded with 6-mercaptopurine.

Science.gov (United States)

Khopade, A J; Jain, N K

2000-01-01

Fine-multiple (water-in-oil-in-water) emulsions were prepared by two-step emulsification using sonication. They were coated with concanavalin-A (Con-A) by three methods. The one involving covalent coupling of Con-A to the multiple emulsion incorporated anchor was better compared with lipid derivatized Con-A anchoring or the glutaraldehyde-based cross-linking method, as shown by the faster rate of dextran-induced aggregation. The selected multiple emulsions were characterized by physical properties such as droplet size, encapsulation efficiency, and zeta potential. Stability parameters such as droplet size, creaming, leakage, and aggregation as a function of relative turbidity were monitored over a 1-month period, which revealed good stability of the formulations. The release profile of 6-mercaptopurine followed zero-order kinetics. Pharmacokinetic studies showed an increase in half-life and bioavailability from multiple emulsion formulations administered intravenously. There was prolonged retention of drug in various tissues of rats when treated with Con-A-coated multiple emulsion as compared with uncoated one. Our study demonstrates the suitability of fine-multiple emulsion for intravenous administration and the potential for prolonged retention of drugs and targeting in biological systems.

Experimental use of emulsion solution on an oil base in the North Togap field

Energy Technology Data Exchange (ETDEWEB)

Kasperskiy, B V; Chumakov, V M; Satvaldyyev, Yu S; Shishkov, S N

1981-01-01

In drilling well 5 of northern Togap of the production association ''Kirgizneft''' in the productive seam (interval 1100-1200 m) represented by argillaceous-sandy Paleogene deposits, an oilbase emulsion solution (OBES) was tested. For fabrication for preparation of the OBES, standard drilling equipment of the unit BU-75 installed on the well was used. In addition to the intake vessel of the pump, a hydraulic disperser designed by the VNIIKRneft' with diameter of the attachments 18 mm was used. A calculated quantity of diesel fuel and oil was added to the intake vessel of the drilling pump. A solution of gossypol resin was added to it and it was carefully mixed by hydromonitors. At the same time a limestone-salt slurry was prepared in the clay mixture. It was then added on channels into the intake vessel with hydrocarbon base. The mixtures were mixed by hydromonitors until an emulsion was obtained which was sent in two cycles through the stream disperser under pressure 4.0-4.5 MPa. After this a calculated quantity of dissolvane was added to the emulsion and it was increased in weight until the assigned density. The additive of dissolvane, not causing a considerable rise in viscosity, promotes the production of a thixotropic solution with fairly high static shear stress. In drilling well 5, because of the advantage of drilling on the bit, the productive seam was stripped in one crushing instead of two as in drilling well 4, where an argillaceous solution on a water base was used. The average well output of well 5 was 6.2 T/day of oil versus 3.8 T/day for well 4.

Amylase catalyzed synthesis of glycosyl acrylates and their polymerization

NARCIS (Netherlands)

Kloosterman, Wouter M.J.; Jovanovic, Danijela; Brouwer, Sander; Loos, Katja

2014-01-01

The enzymatic synthesis of novel (di)saccharide acrylates from starch and 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate and 4-hydroxybutyl acrylate (2-HEA, 2-HEMA and 4-HBA) catalyzed by various commercially available amylase preparations is demonstrated. Both liquefaction and

Hydrodynamics of a continuous vertical settling tank of the plate type with separation of extractive emulsions

International Nuclear Information System (INIS)

Muratov, V.M.; Lyubimov, V.K.; Rakovets, S.M.; Kucharina, G.G.

1987-01-01

The authors present the results of an investigation of the continuous process of separation of extractive emulsion in a long vertical plate-like settling tank used in mixing-settling extractors. The object of study consisted of a section of the mixer-settler with pulsational mixing and a platelike settler 60 mm wide, 1000 mm long, and 300 mm high, made of acrylic plastic. The setup was used to demonstrate the circulation of each of the reagents (phases) in its own contour; they were injected into the mixing chamber by submersible centrifugal pumps, one placed in the volume with the light phase and the other in the volume with the heavy phase. After separation in the settling tank the liquid phases were each continuously poured into their own volume

Comparative Evaluation of Effect of Water Absorption on the Surface Properties of Heat Cure Acrylic: An in vitro Study

OpenAIRE

Chandu, G S; Asnani, Pooja; Gupta, Siddarth; Faisal Khan, Mohd.

2015-01-01

Background: Use of alkaline peroxide denture cleanser with different temperature of water could cause a change in surface hardness of the acrylic denture and also has a bleaching effect. The purpose of the study was to determine the effect of increased water content during thermal cycling of hot water-treated acrylic on the surface hardness of acrylic denture base when compared to warm water treated acrylic. And to compare the bleaching effect of alkaline peroxide solution on the acrylic dent...

Acrylated Palm Oil Resins for Radiation (UV) Curing of Over Print Varnish (OPV)

International Nuclear Information System (INIS)

Norshamsul Arif; Mohd Hilmi Mahmood; Khairul Zaman Mohd Dahlan; Rosley Che Ismail; Flora Sim; Sharilla Muhammad Faizal

2010-01-01

The purpose of this project was to determine the effects of Acrylated Epoxidized Palm Oil (EPOLA) on a radiation (UV) curing Over Print Varnish (OPV) application. The initial target was to produce an environmentally friendly resin (non-VOC) and reduce the dependence on petroleum (hydrocarbon) based products which are more toxic. Toxicity was determined via Acute Oral Toxicity (LD50), OECD 401 and Acute Toxicity (Dermal), OECD 402 technique whilst the reactivity, chemical resistance and other physical properties were obtained from actual printing application test. The developed EPOLA resin was combined with acrylated monomers, photo initiator(s) and additives in typical OPV formulation before being chemically converted into protective glossy printed film under Ultra Violet (UV-C) light. The gloss, flexibility and adhesion effects are significantly greater than conventional OPV epoxy based coupled with further extremely low irritancy to skin. The contributions of this project are twofold. First, the toxicity of developed acrylated Palm Oil resin is certainly lower than conventional epoxy acrylates resin. Secondly, the benefits towards radiation curing OPV applications were significantly demonstrated. (author)

Structural modification of swai-fish (Pangasius hypophthalmus)-based emulsions containing non-meat protein additives by ultra-high pressure and thermal treatments

Science.gov (United States)

Techarang, Jiranat; Apichartsrangkoon, Arunee; Phanchaisri, Boonrak; Pathomrungsiyoungkul, Pattavara; Sriwattana, Sujinda

2017-07-01

Swai-fish emulsions containing fermented soybeans (thua nao and rice-koji miso) were pressurized at 600 MPa for 20 min or heated at 72°C for 30 min. The fish batters were blended with soy protein isolate (SPI) or whey protein concentrate (WPC) to stabilize the emulsions. The processed fish emulsions were then subjected to physical, chemical and microbiological examinations. The results of gel strength and water-holding potential showed that SPI addition yielded higher impact on these properties than WPC addition, which was also confirmed by the interactions between SPI and native fish proteins depicted by electrophoregrams. The frequency profiles suggested that the heated gels had a greater storage and loss moduli than pressurized gels, while pressurized WPC set-gel displayed larger loss tangent (the predominance of viscous moiety) than those pressurized SPI set-gel. High bacteria and spore counts of B. subtilis (residual of the thua nao) were observed in both pressurized and heated fish-based emulsions.

Waterborne hyperbranched alkyd-acrylic resin obtained by miniemulsion polymerization

Directory of Open Access Journals (Sweden)

Edwin Murillo

Full Text Available Abstract Four waterborne hyperbranched alkyd-acrylic resins (HBRAA were synthesized by miniemulsion polymerization from a hyperbranched alkyd resin (HBR, methyl methacrylate (MMA, butyl acrylate (BA and acrylic acid (AA, by using benzoyl peroxide (BPO and ammonium persulfate (AP as initiators. The reaction between HBR and acrylic monomers was evidenced by differential scanning calorimetric (DSC, nuclear magnetic resonance (NMR and gel permeation chromatography (GPC. The conversion percentage, glass transition temperature (Tg, content of acrylic polymer (determined by soxhlet extraction and molecular weight increased with the content of acrylic monomers used in the synthesis. The main structure formed during the synthesis was the HBRAA. The analysis by dynamic light scattering (DLS showed that the particle size distribution of HBRAA2, HBRAA3 and HBRAA4 resins were mainly monomodal. The film properties (gloss, flexibility, adhesion and drying time of the HBRAA were good.

Development of novel zein-sodium caseinate nanoparticle (ZP)-stabilized emulsion films for improved water barrier properties via emulsion/solvent evaporation.

Science.gov (United States)

Wang, Li-Juan; Yin, Ye-Chong; Yin, Shou-Wei; Yang, Xiao-Quan; Shi, Wei-Jian; Tang, Chuan-He; Wang, Jin-Mei

2013-11-20

This work attempted to develop novel high barrier zein/SC nanoparticle (ZP)-stabilized emulsion films through microfluidic emulsification (ZPE films) or in combination with solvent (ethyl acetate) evaporation techniques (ZPE-EA films). Some physical properties, including tensile and optical properties, water vapor permeability (WVP), and surface hydrophobicity, as well as the microstructure of ZP-stabilized emulsion films were evaluated and compared with SC emulsion (SCE) films. The emulsion/solvent evaporation approach reduced lipid droplets of ZP-stabilized emulsions, and lipid droplets of ZP-stabilized emulsions were similar to or slightly lower than that of SC emulsions. However, ZP- and SC-stabilized emulsion films exhibited a completely different microstructure, nanoscalar lipid droplets were homogeneously distributed in the ZPE film matrix and interpenetrating protein-oil complex networks occurred within ZPE-EA films, whereas SCE films presented a heterogeneous microstructure. The different stabilization mechanisms against creaming or coalescence during film formation accounted for the preceding discrepancy of the microstructures between ZP-and SC-stabilized emulsion films. Interestingly, ZP-stabilized emulsion films exhibited a better water barrier efficiency, and the WVP values were only 40-50% of SCE films. A schematic representation for the formation of ZP-stabilized emulsion films was proposed to relate the physical performance of the films with their microstructure and to elucidate the possible forming mechanism of the films.

Flexural Strength of Acrylic Resin Denture Bases Processed by Two Different Methods

Directory of Open Access Journals (Sweden)

Jafar Gharechahi

2014-09-01

Full Text Available Background and aims. The aim of this study was to compare flexural strength of specimens processed by conventional and injection-molding techniques. Materials and methods. Conventional pressure-packed PMMA was used for conventional pressure-packed and injection-molded PMMA was used for injection-molding techniques. After processing, 15 specimens were stored in distilled water at room temperature until measured. Three-point flexural strength test was carried out. Statistical analysis was carried out by SPSS using t-test. Statistical significance was defined at P<0.05. Results. Flexural strength of injection-polymerized acrylic resin specimens was higher than that of theconventional method (P=0.006. This difference was statistically significant (P=0.006. Conclusion. Within the limitations of this study, flexural strength of acrylic resin specimens was influenced by the mold-ing technique.

Microfluidic methods to study emulsion formation

NARCIS (Netherlands)

Muijlwijk, Kelly

2017-01-01

Emulsions are dispersions of one liquid in another that are commonly used in various products, and methods such as high-pressure homogenisers and colloid mills are used to form emulsions. The size and size distribution of emulsion droplets are important for the final product properties and thus

Allergic contact dermatitis to acrylates in disposable blue diathermy pads.

Science.gov (United States)

Sidhu, S. K.; Shaw, S.

1999-01-01

We report 2 cases of elicitation of allergic contact dermatitis to acrylates from disposable blue diathermy pads used on patients who underwent routine surgery. Their reactions were severe, and took approximately 5 weeks to resolve. Both patients gave a prior history of finger tip dermatitis following the use of artificial sculptured acrylic nails, which is a common, but poorly reported, cause of acrylate allergy. Patch testing subsequently confirmed allergies to multiple acrylates present in both the conducting gel of disposable blue diathermy pads, and artificial sculptured acrylic nails. We advocate careful history taking prior to surgery to avoid unnecessary exposure to acrylates in patients already sensitized. Images Figure 1 Figure 2 PMID:10364952

Multi-plane photomicrography of 3-D objects in nuclear emulsions

International Nuclear Information System (INIS)

Baranov, V.I.

1994-01-01

A new method of photomicrographing charged particle tracks in nuclear emulsions is proposed. It is based on summarizing the inverse (dark field) object partial images, obtained at different emulsion layer depths on one negative. This method permits to get, for example, nuclear event stereo pictures with large image field depth. 5 refs., 5 figs

A new apparatus for track-analysis in nuclear track emulsion based on a CCD-camera device

International Nuclear Information System (INIS)

Ganssauge, E.

1993-01-01

A CCD camera-based, image-analyzing system for automatic evaluation of nuclear track emulsion chambers is presented. The stage of a normal microscope moves using three remote controlled stepping motors with a step size of 0.25 μm. A CCD-camera is mounted on tope of the microscope in order to register the nuclear emulsion. The camera has a resolution capable of differentiating single emulsion-grains (0.6 μm). The camera picture is transformed from analogue to digital signals and stored by a frame grabber. Some background-picture elements can be eliminated by applying cuts on grey levels. The central computer processes the picture, correlates the single picture points, the coordinates and the grey-levels, such that in the end one has a unique assignment of each picture point to an address on the hard disk for a given plate. After repetition of this procedure for several plates by means of an appropriate software (for instance our vertex program [1]). the coordinates of the points are combined to tracks, and a variety of distributions like pseudorapidity-distributions can be calculated and presented on the terminal. (author)

Amphiphilic copolymers based on PEG-acrylate as surface active water viscosifiers : Towards new potential systems for enhanced oil recovery

NARCIS (Netherlands)

Raffa, Patrizio; Broekhuis, Antonius A.; Picchioni, Francesco

2016-01-01

With the purpose of investigating new potential candidates for enhanced oil recovery (EOR), amphiphilic copolymers based on Poly(ethylene glycol) methyl ether acrylate (PEGA) have been prepared by Atom Transfer Radical Polymerization (ATRP). A P(PEGA) homopolymer, a block copolymer with styrene

Shear bond strength of a denture base acrylic resin and gingiva-colored indirect composite material to zirconia ceramics.

Science.gov (United States)

Kubochi, Kei; Komine, Futoshi; Fushiki, Ryosuke; Yagawa, Shogo; Mori, Serina; Matsumura, Hideo

2017-04-01

To evaluate the shear bond strengths of two gingiva-colored materials (an indirect composite material and a denture base acrylic resin) to zirconia ceramics and determine the effects of surface treatment with various priming agents. A gingiva-colored indirect composite material (CER) or denture base acrylic resin (PAL) was bonded to zirconia disks with unpriming (UP) or one of seven priming agents (n=11 each), namely, Alloy Primer (ALP), Clearfil Photo Bond (CPB), Clearfil Photo Bond with Clearfil Porcelain Bond Activator (CPB+Act), Metal Link (MEL), Meta Fast Bonding Liner (MFB), MR. bond (MRB), and V-Primer (VPR). Shear bond strength was determined before and after 5000 thermocycles. The data were analyzed with the Kruskal-Wallis test and Steel-Dwass test. The mean pre-/post-thermalcycling bond strengths were 1.0-14.1MPa/0.1-12.1MPa for the CER specimen and 0.9-30.2MPa/0.1-11.1MPa for the PAL specimen. For the CER specimen, the ALP, CPB, and CPB+Act groups had significantly higher bond strengths among the eight groups, at both 0 and 5000 thermocycles. For the PAL specimen, shear bond strength was significantly lower after thermalcycling in all groups tested. After 5000 thermocycles, bond strengths were significantly higher in the CPB and CPB+Act groups than in the other groups. For the PAL specimens, bond strengths were significantly lower after thermalcycling in all groups tested. The MDP functional monomer improved bonding of a gingiva-colored indirect composite material and denture base acrylic resin to zirconia ceramics. Copyright © 2016 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

Radiation-curing of acrylate composites including carbon fibres: A customized surface modification for improving mechanical performances

International Nuclear Information System (INIS)

Martin, Arnaud; Pietras-Ozga, Dorota; Ponsaud, Philippe; Kowandy, Christelle; Barczak, Mariusz; Defoort, Brigitte; Coqueret, Xavier

2014-01-01

The lower transverse mechanical properties of radiation-cured acrylate-based composites reinforced with carbon-fibre with respect to the thermosettable analogues was investigated from the viewpoint of chemical interactions at the interface between the matrix and the carbon material. XPS analysis of representative commercial carbon fibres revealed the presence of a significant amount of chemical functions potentially exerting an adverse effect on the initiation and propagation of the free radical polymerization initiated under high energy radiation. The EB-induced polymerization of n-butyl acrylate as a simple model monomer was conducted in the presence of various aromatic additives exhibiting a strong inhibiting effect, whereas thiols efficiently sensitize the initiation mechanism and undergo transfer reactions. A method based on the surface modification of sized fibres by thiomalic acid is proposed for overcoming the localized inhibition phenomenon and for improving the mechanical properties of the resulting acrylate-based composites. - Highlights: • Surface functions of C-fibres are analyzed for their effect on radical reaction. • Irradiation of nBu-acrylate in presence of aromatic additives reveals inhibition. • Thiol groups sensitize the radiation-initiated polymerization of nBu-acrylate. • Modification of C-fibres with thiomalic acid enhances composite properties

Modelling of Emulsion Flow in Porous Media

Energy Technology Data Exchange (ETDEWEB)

Abou-Kassem, J.H. [UAE University (United Arab Emirates); Farouq Ali, S.M. [UAE University (United Arab Emirates)

1995-06-01

Oil recovery methods predominantly involve emulsion formation. Oil recovery simulation requires the incorporation of emulsion characteristics and flow in porous media, in order to optimize oil recovery from petroleum reservoirs. This paper explored the nature and rheology of emulsions, and evaluated several models of flow of Newtonian and non-Newtonian fluids in porous media. It also summarized in situ emulsion formation in porous media. A model for both Newtonian and non-Newtonian emulsion fluid flow was proposed, with special emphasis on pore size, and tortuosity in the porous media.

Nanocellulose-stabilized Pickering emulsions and their applications.

Science.gov (United States)

Fujisawa, Shuji; Togawa, Eiji; Kuroda, Katsushi

2017-01-01

Pickering emulsion, which is an emulsion stabilized by solid particles, offers a wide range of potential applications because it generally provides a more stable system than surfactant-stabilized emulsion. Among various solid stabilizers, nanocellulose may open up new opportunities for future Pickering emulsions owing to its unique nanosizes, amphiphilicity, and other favorable properties (e.g. chemical stability, biodegradability, biocompatibility, and renewability). In this review, the preparation and properties of nanocellulose-stabilized Pickering emulsions are summarized. We also provide future perspectives on their applications, such as drug delivery, food, and composite materials.

Poly (ethylene oxide)-block-poly (n-butyl acrylate)-blockpoly (acrylic acid) triblock terpolymers with highly asymmetric hydrophilic blocks: synthesis and aqueous solution properties

OpenAIRE

Petrov, P. (Petar); Yoncheva, K. (Krassimira); Mokreva, P. (Pavlina); Konstantinov, S. (Spiro); Irache, J.M. (Juan Manuel); Müller, A.H.E. (Axel H.E.)

2013-01-01

The synthesis and aggregation behaviour in aqueous media of novel amphiphilic poly(ethylene oxide)- block-poly(n-butyl acrylate)-block-poly(acrylic acid) (PEO–PnBA–PAA) triblock terpolymers were studied. Terpolymers composed of two highly asymmetric hydrophilic PEO (113 monomer units) and PAA (10–17 units) blocks, and a longer soft hydrophobic PnBA block (163 or 223 units) were synthesized by atom transfer radical polymerisation (ATRP) of n-butyl acrylate and tert-butyl acrylate ...

Recovery of Acrylic Acid Using Calcium Peroxide Nanoparticles: Synthesis, Characterisation, Batch Study, Equilibrium, and Kinetics

Directory of Open Access Journals (Sweden)

B. S. De

2018-03-01

Full Text Available Recovery of acrylic acid from aqueous solution using low-cost CaO2 nanoparticles was investigated. CaO2 nanoparticles were synthesized by co-precipitation technique and characterised using XRD and FTIR. A mechanism was proposed for adsorption of acrylic acid onto CaO2 nanoparticles based on FTIR analysis. Acrylic acid recovery is highly dependent on contact time, CaO2 nanoparticle dosage, initial acrylic concentration, and temperature. Langmuir, Freundlich, Dubinin-Radushkevich, Tempkin, Hill, Redlich-Peterson, Sips and Toth isotherms were used and well represented by Redlich-Peterson isotherm (R2 = 0.9998 as compared to other isotherms. Kinetic studies revealed pseudo-second-order kinetics (k2 = 1.962·10–4 g mg–1 min–1 for adsorption of acrylic acid onto CaO2 nanoparticles. CaO2 nanoparticles exhibited high acrylic acid recovery over varied concentration ranges. The acrylic acid can be regenerated by desorption from the surface of adsorbent and utilised for numerous applications. The presented results may be useful for the design of adsorption system using nanoparticles, which can be extended to other systems.

Ethyl Ferulate, a Component with Anti-Inflammatory Properties for Emulsion-Based Creams

Directory of Open Access Journals (Sweden)

Ana C. Nazaré

2014-06-01

Full Text Available Ethyl ferulate (FAEE has been widely studied due to its beneficial heath properties and, when incorporated in creams, shows a high sun protection capacity. Here we aimed to compare FAEE and its precursor, ferulic acid (FA, as free radical scavengers, inhibitors of oxidants produced by leukocytes and the alterations in rheological properties when incorporated in emulsion based creams. The cell-free antiradical capacity of FAEE was decreased compared to FA. However, FAEE was more effective regarding the scavenging of reactive oxygen species produced by activated leukocytes. Stress and frequency sweep tests showed that the formulations are more elastic than viscous. The viscoelastic features of the formulations were confirmed in the creep and recovery assay and showed that the FAEE formulation was less susceptive to deformation. Liberation experiments showed that the rate of FAEE release from the emulsion was slower compared to FA. In conclusion, FAEE is more effective than FA as a potential inhibitor of oxidative damage produced by oxidants generated by leukocytes. The rheological alterations caused by the addition of FAEE are indicative of lower spreadability, which could be useful for formulations used in restricted areas of the skin.

Ethyl ferulate, a component with anti-inflammatory properties for emulsion-based creams.

Science.gov (United States)

Nazaré, Ana C; de Faria, Carolina M Q G; Chiari, Bruna G; Petrônio, Maicon S; Regasini, Luis O; Silva, Dulce H S; Corrêa, Marcos A; Isaac, Vera L B; da Fonseca, Luiz M; Ximenes, Valdecir F

2014-06-17

Ethyl ferulate (FAEE) has been widely studied due to its beneficial heath properties and, when incorporated in creams, shows a high sun protection capacity. Here we aimed to compare FAEE and its precursor, ferulic acid (FA), as free radical scavengers, inhibitors of oxidants produced by leukocytes and the alterations in rheological properties when incorporated in emulsion based creams. The cell-free antiradical capacity of FAEE was decreased compared to FA. However, FAEE was more effective regarding the scavenging of reactive oxygen species produced by activated leukocytes. Stress and frequency sweep tests showed that the formulations are more elastic than viscous. The viscoelastic features of the formulations were confirmed in the creep and recovery assay and showed that the FAEE formulation was less susceptive to deformation. Liberation experiments showed that the rate of FAEE release from the emulsion was slower compared to FA. In conclusion, FAEE is more effective than FA as a potential inhibitor of oxidative damage produced by oxidants generated by leukocytes. The rheological alterations caused by the addition of FAEE are indicative of lower spreadability, which could be useful for formulations used in restricted areas of the skin.

Synthesis and optimization of EA-MMA copolymer emulsion%EA-MMA共聚乳液合成工艺及优化

Institute of Scientific and Technical Information of China (English)

张成芬; 武玉民

2011-01-01

以丙烯酸乙酯(EA)和甲基丙烯酸甲酯(MMA)为共聚单体、过硫酸钾(KPS)为引发剂、十二烷基硫酸钠(SDS)和壬基酚聚氧乙烯醚(OP-10)为复合乳化剂,采用乳液聚合法合成出一种稳定的EA-MMA乳液.通过单因素试验法考察了乳化剂浓度、引发剂浓度、反应温度和反应时间等因素对乳液平均粒径和单体转化率的影响,并采用正交试验法进一步优选出制备EA-MMA乳液的最佳工艺条件.结果表明:当w(乳化剂)=2.0%、w(引发剂)=0.60%、反应时间为4 h和反应温度为80℃时,制成的EA-MMA乳液较稳定,并且单体转化率相对最高.%With ethyl acrylate(EA) and methyl methacrylate( MMA) as comonomers ,potassium persulfate(KPS)as initiator,and sodium dodecyl sulfate(SDS) and nonylphenol ethoxylates(OP-10) as composite emulsifier,a stable EA-MMA emulsion was synthesized by emulsion polymerization. The influences of some factor(such as emulsifier concentration,initiator concentration,reaction temperature and reaction time) on average particle size of emulsion and monomer conversion rate were investigated by single factor experiment method,then the optimal process conditions of preparing EA-MMA emulsion were preferred by orthogonal experiment method. The results showed that the EA-MMA emulsion had better stability and relatively highest monomer conversion rate when the mass fractions of emulsifier and initiator were 2.0％ and 0.60％ respectively,the reaction time and reaction temperature were 4 h and 80 ℃ respectively.

Analysis of poly(styrene-co-methyl acrylate) and poly(styrene-co-butyl acrylate) by high-performance liquid chromatography

NARCIS (Netherlands)

Sparidans, R.W.; Claessens, H.A.; van Doremaele, G.H.J.; Herk, van A.M.

1990-01-01

Poly(styrene—co-methyl acrylate) and poly(styrene—co-butyl acrylate) were separated according to their chemical composition by gradient elution. The chromatographic separation on silica was optimized for a gradient ranging from n-heptane as a non-solvent to dichloromethane containing a small amount

Freeze-Thaw Performance and Moisture-Induced Damage Resistance of Base Course Stabilized with Slow Setting Bitumen Emulsion-Portland Cement Additives

Directory of Open Access Journals (Sweden)

Mojtaba Shojaei Baghini

2015-01-01

Full Text Available Freeze-thaw (FT cycles and moisture susceptibility are important factors influencing the geotechnical characteristics of soil-aggregates. Given the lack of published information on the behavior of cement-bitumen emulsion-treated base (CBETB under environmental conditions, especially freezing and thawing, this study investigated the effects of these additives on the CBETB performance. The primary goal was to evaluate the resistance of CBETB to moisture damage by performing FT, Marshall conditioning, and AASHTO T-283 tests and to evaluate the long-term stripping susceptibility of CBETB while also predicting the liquid antistripping additives to assess the mixture’s durability and workability. Specimens were stabilized with Portland cement (0%–6%, bitumen emulsion (0%–5%, and Portland cement-bitumen emulsion mixtures and cured for 7 days, and their short- and long-term performances were studied. Evaluation results of both the Marshall stability ratio and the tensile strength ratio show that the additions of additives increase the resistance of the mixtures to moisture damage. Results of durability tests performed for determining the resistance of compacted specimens to repeated FT cycles indicate that the specimen with the 4% cement-3% bitumen emulsion mixture significantly improves water absorption, volume changes, and weight losses. This indicates the effectiveness of this additive as a road base stabilizer with excellent engineering properties for cold regions.

Studies of water-in-oil emulsions : testing of emulsion formation in OHMSETT

International Nuclear Information System (INIS)

Fingas, M.; Fieldhouse, B.

2001-01-01

A study was conducted to determine the stability of water-in-oil emulsions in the OHMSETT tank facility. The results were then compared with previous laboratory studies which suggested that the stability of emulsions can be grouped into four categories, stable, unstable, meso-stable and entrained. It has been determined that entrained emulsions can retain oil by viscous forces long enough for interfacial agents, resins and asphaltenes to stabilize the droplets. This paper also described the difference in viscosity between the 4 categories of emulsion stability. The OHMSETT tests were conducted in two series of one week each. The first series of tests were conducted in July and involved 12 experiments on 2 different types of oils which were placed at varying thicknesses on the water. The second set of tests were conducted in November and involved 12 experiments on 6 oils. The rheological properties of the oils were measured and compared to the same oils undergoing emulsification in the laboratory. The oils and water-in-oil states produced were found to have analogous properties between the laboratory and the first set of tests at the OHMSETT facility. All the oils tested produced entrained water-in-oil states in both the laboratory and the test tank. The energy in the two test conditions was found to be similar, with the OHMSETT emulsions similar to one produced in the laboratory at high energies. The second series of tests at OHMSETT did not result in the expected water in-oil- states. This unexpected result was most likely due to the residual surfactant from an earlier dispersant experiment. The study showed that the conditions for emulsion formation are analogous in the OHMSETT tank and in the laboratory tests. The level of energy is considered to be the major variant. It was concluded that the energy levels between the laboratory mixing experiments and the OHMSETT is similar. It was shown that surfactants left over from dispersant testing inhibited the formation

Emulsion stability measurements by single electrode capacitance probe (SeCaP) technology

International Nuclear Information System (INIS)

Schüller, R B; Løkra, S; Egelandsdal, B; Salas-Bringas, C; Engebretsen, B

2008-01-01

This paper describes a new and novel method for the determination of the stability of emulsions. The method is based on the single electrode capacitance technology (SeCaP). A measuring system consisting of eight individual measuring cells, each with a volume of approximately 10 ml, is described in detail. The system has been tested on an emulsion system based on whey proteins (WPC80), oil and water. Xanthan was added to modify the emulsion stability. The results show that the new measuring system is able to quantify the stability of the emulsion in terms of a differential variable. The whole separation process is observed much faster in the SeCaP system than in a conventional separation column. The complete separation process observed visually over 30 h is seen in less than 1.4 h in the SeCaP system

Food enrichment with marine phospholipid emulsions

DEFF Research Database (Denmark)

Lu, Henna Fung Sieng; Nielsen, Nina Skall; Baron, Caroline P.

marine PL emulsions with and without addition of fish oil. The oxidative stability of marine PL emulsions was significantly influenced by the chemical composition of marine PL used for emulsions preparation. For instance, emulsions with good oxidative stability could be obtained when using raw materials...... with high purity, low fish oil content and high PL, cholesterol and α-tocopherol content. In addition, non-enzymatic browning reactions may also affect the oxidative stability of the marine PL emulsion. These reactions included Strecker degradation and pyrrolization, and their occurrence were due......Many studies have shown that marine phospholipids (PL) provide more advantages than fish oil. They seem to have better bioavailability, better resistance towards oxidation and higher content of eicosapentaenoic acids and docosahexaenoic acids than fish oil, which essentially contains triglycerides...

Contact allergy to epoxy (meth)acrylates.

Science.gov (United States)

Aalto-Korte, Kristiina; Jungewelter, Soile; Henriks-Eckerman, Maj-Len; Kuuliala, Outi; Jolanki, Riitta

2009-07-01

Contact allergy to epoxy (meth)acrylates, 2,2-bis[4-(2-hydroxy-3-methacryloxypropoxy) phenyl]propane (bis-GMA), 2,2-bis[4-(2-hydroxy-3-acryloxypropoxy)phenyl]-propane (bis-GA), 2,2-bis[4-(methacryl-oxyethoxy)phenyl] propane (bis-EMA), 2,2-bis[4-(methacryloxy)phenyl]-propane (bis-MA), and glycidyl methacrylate (GMA) is often manifested together with contact allergy to diglycidyl ether of bisphenol A (DGEBA) epoxy resin. To analyse patterns of concomitant allergic reactions to the five epoxy (meth)acrylates in relation to exposure. We reviewed the 1994-2008 patch test files at the Finnish Institute of Occupational Health (FIOH) for reactions to the five epoxy (meth)acrylates, and examined the patients' medical records for exposure. Twenty-four patients had an allergic reaction to at least one of the studied epoxy (meth)acrylates, but specific exposure was found only in five patients: two bis-GMA allergies from dental products, two bis-GA allergies from UV-curable printing inks, and one bis-GA allergy from an anaerobic glue. Only 25% of the patients were negative to DGEBA epoxy resin. The great majority of allergic patch test reactions to bis-GMA, bis-GA, GMA and bis-EMA were not associated with specific exposure, and cross-allergy to DGEBA epoxy resin remained a probable explanation. However, independent reactions to bis-GA indicated specific exposure. Anaerobic sealants may induce sensitization not only to aliphatic (meth)acrylates but also to aromatic bis-GA.

21 CFR 177.1340 - Ethylene-methyl acrylate copolymer resins.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ethylene-methyl acrylate copolymer resins. 177.1340... Basic Components of Single and Repeated Use Food Contact Surfaces § 177.1340 Ethylene-methyl acrylate copolymer resins. Ethylene-methyl acrylate copolymer resins may be safely used as articles or components of...

Long-term toughness of photopolymerizable (meth)acrylate networks in aqueous environments.

Science.gov (United States)

Smith, Kathryn E; Trusty, Phillip; Wan, Beatrice; Gall, Ken

2011-02-01

Photopolymerizable (meth)acrylate networks are potentially advantageous biomaterials due to their ability to be formed in situ, their fast synthesis rates and their tailorable material properties. The objective of this study was to evaluate how immersion time in phosphate-buffered saline (PBS) affects the toughness of photopolymerizable methyl acrylate (MA)-co-methyl methacrylate-co-poly(ethylene glycol) dimethacrylate networks containing various concentrations of MA. Stress-strain behavior was determined by performing tensile strain to failure testing after soaking in PBS for different periods (1 day up to 9 months). In tandem, differential scanning calorimetry and PBS content measurements were undertaken at each time point in order to determine whether time-dependent changes in toughness were related to changes in T(g) or PBS absorption. The effect of immersion time on network toughness was shown to be dependent upon composition in a manner related to the viscoelastic state of the polymer upon initial immersion in PBS. The results demonstrate that tough acrylate-based materials may not maintain their toughness after several months in PBS. In addition, decreasing the PBS content by changing the network hydrophobicity resulted in better toughness maintenance after 9 months. The results provide a possible means to toughen various amorphous acrylate-based implant materials that are being explored for load-bearing biomedical applications, beyond the systems considered in this work. Published by Elsevier Ltd.

Use of Acrylic Acid Sodium Acrylate Polymer to Maintain Cocoa Seed Viability

Directory of Open Access Journals (Sweden)

Pudji Rahardjo

2010-08-01

Full Text Available The main problem of cocoa seed storage is moisture content of the seeds because cocoa seeds will germinate if cocoa seeds moisture content is high. The objective of this research is to maintain the cocoa seeds viability in storage using acrylic acid sodium acrylate polymer (AASAP. The function of AASAP is to absorb humidity in storage due to their ability to retain water and to prevent water loss. The experiment was conducted in a laboratory of Indonesian Coffee and Cocoa Research Institute and in Kaliwining Experimental Garden. This experiment was arranged by factorial randomized complete design, in wich AASAP dosages 0%; 0.1% (0.1 g/100 seeds; 0.2% (0.2 g/100 seeds, 0.3% (0.3 g/100 seeds, 0,4% (0,4g/100 seeds, combined with seeds storage period 1, 2, 3 and 4 weeks. The experiment used 3 replications and each repli cation used 100 seeds. Parameter of observation consisted of percentage of seeds germinated in storage, percentage of seeds infected by fungi in storage, seeds moisture content, percentage of seeds germination after storage, and early growth of cocoa seedlings. The results of the experiment showed that AASAP application with some dosages cocoa seeds storage cause to germinate in storage during 2 weeks. AASAP application with some dosages in cocoa seeds storage for 2 weeks would not result in infection by fungi and did not significantly affect seed germination after storage for 1, 2 and 4 weeks, and percentage of germination of cocoa seed after storage for 3 weeks decreased with increase dosage of AASAP. Higher dosage of AASAP would reduce early growth of cocoa seedling. Key words : Theobroma cacao, seed, acrylic acid sodium acrylate, seed storage, viabilty.

A simple and low-cost fully 3D-printed non-planar emulsion generator

KAUST Repository

Zhang, Jiaming

2015-12-23

Droplet-based microfluidic devices provide a powerful platform for material, chemical and biological applications based on droplet templates. The technique traditionally utilized to fabricate microfluidic emulsion generators, i.e. soft-lithography, is complex and expensive for producing three-dimensional (3D) structures. The emergent 3D printing technology provides an attractive alternative due to its simplicity and low-cost. Recently a handful of studies have already demonstrated droplet production through 3D-printed microfluidic devices. However, these devices invariably use purely two-dimensional (2D) flow structures. Herein we apply 3D printing technology to fabricate simple and low-cost 3D miniaturized fluidic devices for droplet generation (single emulsion) and droplet-in-droplet (double emulsion) without need for surface treatment of the channel walls. This is accomplished by varying the channel diameters at the junction, so the inner liquid does not touch the outer walls. This 3D-printed emulsion generator has been successfully tested over a range of conditions. We also formulate and demonstrate, for the first time, uniform scaling laws for the emulsion drop sizes generated in different regimes, by incorporating the dynamic contact angle effects during the drop formation. Magnetically responsive microspheres are also produced with our emulsion templates, demonstrating the potential applications of this 3D emulsion generator in chemical and material engineering.

STUDY REGARDING THE DESTABILIZATION OF STABLE EMULSIONS FROM SUPLAC AREA

Directory of Open Access Journals (Sweden)

IULIANA VERONICA GHEŢIU

2016-12-01

Full Text Available Emulsions from the wells in the Suplac area create great difficulties in removing water due to their specifications. A complex study was conducted in order to eliminate water from emulsions using alkaline-surfactants. The choice of surfactant was made after the chromatographic SARA analysis of emulsions and the determination of their physical properties: density, viscosity, organic acidity. The samples were taken from two wells in the Suplac area. In the case of samples from A well the variation of density is 907 - 955 kg·m-3 for crude oil and 928 - 970 kg·m-3 for emulsion, while the rheological behavior of the emulsion varies between 0.680 to 0.995 Pa·s at a temperature of 25 °C and between 0.049 to 0.328 Pa·s at a temperature of 80 °C. For samples from B well the variation of density is 855 - 905 kg·m-3 for crude oil and 939 - 970 kg·m-3 for emulsion, while the rheological behavior of the emulsion varies between 0.149 to 0.797 Pa·s at a temperature of 25 °C and between 0.014 to 0.397 Pa·s at a temperature of 80 °C. The justification for choosing R - DP surfactant like reagent was based on laboratory tests which showed a maximum efficiency at 80 °C (95.69 for B and 98.75 % for A.

Ionizing radiation method for forming acrylic pressure sensitive adhesives and coated substrates

International Nuclear Information System (INIS)

Dowbenko, R.; Christenson, R.M.

1975-01-01

Pressure-sensitive adhesive having improved adhesive properties are formed by subjecting a mixture comprising a monomer selected from the group consisting of alkyl acrylates, hydroxyalkyl acrylates, alkoxyalkyl acrylates, cyanoalkyl acrylates, alkyl methacrylates, hydroxyalkyl methacrylates, alkoxyalkyl methacrylates, cyanoalkyl methacrylates, N-alkoxymethylacrylamides, and N-alkoxymethylmethacrylamides, and a homopolymer or copolymer selected from the group consisting of polymers of alkyl acrylates, hydroxyalkyl acrylates, alkoxyalkyl acrylates, cyanoalkyl acrylates, alkyl methacrylates, hydroxyalkyl methacrylates, alkoxyalkyl methacrylates, cyanoalkyl methacrylates, acrylamide, methacrylamide, N-(substituted alkyl) acrylamides, N-(substituted alkyl) methacrylamides, alkyl acrylamides, alkyl methacrylamides, and N-alkoxymethylacrylamides and N-alkoxymethylmethacrylamides to ionizing irradiation. The adhesive material finds utility as binding resins in laminates, coatings on substrates, and as film adhesives. (U.S.)

COMPARATIVE ANALYSIS OF WATER SORPTION BY DIFFERENT ACRYLIC MATERIALS

Directory of Open Access Journals (Sweden)

Milena Kostić

2014-06-01

Full Text Available Acrylic materials are used daily for the production of mobile dental restorations and orthodontic appliances. The presence of residual monomer, as a product of incomplete polymerisation of material, results in more porous structure of the material, which greatly reduces the mechanical and physical quality of the acrylic restorations and increases the absorption of liquids. The aim of this study was to examine the water absorption of different types of resin material. In the study it was assumed that the cold polymerized acrylates show a greater potential for absorbing fluid from the environment in relation to the hot polymerized acrylic. The study included two hot and two cold polymerized acrylates, and cold polymerized acrylate impregnated with aesthetic pearls. In order to determine the degree of water absorption, the mass of the samples was measured before and after one day, seven days and thirty days of immersion in a water bath of body temperature. The tested hot and cold polymerized acrylates after immersion in water bath showed standard values of water absorption. The degree of water absorption was not significantly influenced by the type and manner of polymerisation. Water absorption values were significantly higher after seven days and thirty days of water storage relative to the observational period of one day.

Response of nuclear emulsions to ionizing radiations

International Nuclear Information System (INIS)

Katz, R.; Pinkerton, F.E.

1975-01-01

Heavy ion tracks in Ilford K-2 emulsion are simulated with a computer program which makes use of the delta-ray theory of track structure, and the special assumption that the response of this emulsion to gamma-rays is 8-or-more hit. The Ilford K-series of nuclear emulsions is produced from a parent stock called K.0 emulsion, sensitized to become K.1 to K.5, and desensitized to become K-1 to K-3. Our simulations demonstrate that the emulsions K.5 through K.0 to K-1 are 1-or-more hit detectors, while K-2 is an 8-or-more hit detector. We have no data for K-3 emulsion. It would appear that emulsions of intermediate hittedness might be produced by an intermediate desensitization, to mimic or match the RBE-LET variations of biological cells, perhaps to produce a ''rem-dosimeter''. In the K-2 emulsion no developable gains are produced by stopping H, He, and Li ions. The emulsion has ''threshold-like'' properties, resembling etchable track detectors. It should prove useful in the measurement of high LET dose in a strong low LET background, as for pions or neutrons. Since it can be expected to accumulate and repair ''sub-lethal damage'', to display the ion-kill and gamma-kill inactivation modes, the grain-count and track width regimes, it may serve to model biological effects. (auth)

The identification method of the nuclear fragments in emulsions

International Nuclear Information System (INIS)

Jipa, Alexandru; Ocheseanu, Silvia; Caramarcu, Costin; Calin, Marius; Constantin, Florin; Stan, Emil

2003-01-01

The visualization detectors have been successfully used from the beginning of the study of the relativistic nuclear collisions. One of these detectors used in such experiments is the nuclear emulsion. To increase the speed of the passage from pictures to experimental data different methods and tools have been proposed during the time. For identifying the nuclear fragments obtained in the relativistic radioactive beams multiple layers of nuclear emulsions have been exposed in experiments performed at the Synchrophasotron from the JINR Dubna (BECQUEREL Collaboration). The nuclear fragments have been identified using PAVICOM scanning and measuring system. In the present work an identification method based on a real time image processing machine and a reconstruction algorithm based on special conformal transforms is proposed. The results obtained by this method are compared with those obtained using PAVICOM device. Because in this study only pictures have been used, not initial nuclear emulsions, some difficulties in the identification of the nuclear fragments with higher polar angles can appear. Generally, comparable results have been obtained. The authors thank Dr. Pavel Zarubin from JINR Dubna, Laboratory of High Energy Physics, and Dr. Maria Haiduc, Institute of Space Sciences Bucharest-Magurele, for the pictures of the nuclear emulsions exposed in these experiments. (authors)

Synthesis and characterization of acrylated Parkia biglobosa ...

African Journals Online (AJOL)

The results revealed that acid functional acrylic copolymers containing maleic anhydride as a functional co-monomer can successfully be used to modify alkyd resins yielding acrylated resins with better drying, flexibility, scratch hardness, impact resistance and chemical resistance properties. However there exist optimum ...

[Treatment of acrylate wastewater by electrocatalytic reduction process].

Science.gov (United States)

Yu, Li-Na; Song, Yu-Dong; Zhou, Yue-Xi; Zhu, Shu-Quan; Zheng, Sheng-Zhi; Ll, Si-Min

2011-10-01

High-concentration acrylate wastewater was treated by an electrocatalytic reduction process. The effects of the cation exchange membrane (CEM) and cathode materials on acrylate reduction were investigated. It indicated that the acrylate could be reduced to propionate acid efficiently by the electrocatalytic reduction process. The addition of CEM to separator with the cathode and anode could significantly improve current efficiency. The cathode materials had significant effect on the reduction of acrylate. The current efficiency by Pd/Nickel foam, was greater than 90%, while those by nickel foam, the carbon fibers and the stainless steel decreased successively. Toxicity of the wastewater decreased considerably and methane production rate in the biochemical methane potential (BMP) test increased greatly after the electrocatalytic reduction process.

Antioxidant activity and emulsion-stabilizing effect of pectic enzyme treated pectin in soy protein isolate-stabilized oil/water emulsion.

Science.gov (United States)

Huang, Ping-Hsiu; Lu, Hao-Te; Wang, Yuh-Tai; Wu, Ming-Chang

2011-09-14

The antioxidant activity of pectic enzyme treated pectin (PET-pectin) prepared from citrus pectin by enzymatic hydrolysis and its potential use as a stabilizer and an antioxidant for soy protein isolate (SPI)-stabilized oil in water (O/W) emulsion were investigated. Trolox equivalent antioxidant capacity (TEAC) was found to be positively associated with molecular weight (M(w)) of PET-pectin and negatively associated with degree of esterification (DE) of PET-pectin. PET-pectin (1 kDa and 11.6% DE) prepared from citrus pectin after 24 h of hydrolysis by commercial pectic enzyme produced by Aspergillus niger expressed higher α,α-diphenyl-β-picrylhydrazyl (DPPH) radical scavenging activity, TEAC, and reducing power than untreated citrus pectin (353 kDa and 60% DE). The addition of PET-pectin could increase both emulsifying activity (EA) and emulsion stability (ES) of SPI-stabilized O/W emulsion. When the SPI-stabilized lipid droplet was coated with the mixture of PET-pectin and pectin, the EA and ES of the emulsion were improved more than they were when the lipid droplet was coated with either pectin or PET-pectin alone. The amount of secondary oxidation products (thiobarbituric acid reactive substances) produced in the emulsion prepared with the mixture of SPI and PET-pectin was less than the amount produced in the emulsion prepared with either SPI or SPI/pectin. These results suggest that PET-pectin has an emulsion-stabilizing effect and lipid oxidation inhibition ability on SPI-stabilized emulsion. Therefore, PET-pectin can be used as a stabilizer as well as an antioxidant in plant origin in SPI-stabilized O/W emulsion and thus prolong the shelf life of food emulsion.

Emulsion-based synthesis of NaA zeolite nanocrystals and its ...

Indian Academy of Sciences (India)

Administrator

tion is an essential requirement for practical purposes. In addition to ... The stabilized emulsion was then placed in an oil bath at 65 ± 1°C ... machine (Dip Master; Model: 200, CHEMAT Technology .... time of 2 h during hydrothermal treatment.

Long-Chain Diacrylate Crosslinkers and Use of PEG Crosslinks in Poly(potassium acrylate-acrylic acid/Kaolin Composite Superabsorbents

Directory of Open Access Journals (Sweden)

Koroush Kabiri

2013-01-01

Full Text Available Long-chain diacrylate crosslinkers based on linear α,ω-diols were synthesized and characterized using FTIR and 1H NMR spectroscopy. The highest reaction yield (99.5% was due to polyethylene glycol diacrylate 1000 (PEGDA-1000. Then, kaolin-containing poly(potassium acrylate-acrylic acid superabsorbent composites and kaolin-free counterparts were synthesized using PEGDA-1000.The effect of the crosslinker concentration on swelling, rheological and thermo-mechanical properties was investigated. Absorption capacity of the composite hydrogels (having ~38% kaolin was unexpectedly higher than that of kaolin-free hydrogels. This was attributed to an interfering effect of kaolin during the polymerization. Glass transition temperature was increased with crosslinker concentration enhancement and addition of kaolin up to about 10oC and 28oC, respectively. Making such K-containing superabsorbents may be taken as an effective action to achieve more durable and cheaper superabsorbents for agricultural uses.

Study on properties of UV-curable films based on alkali-soluble photosensitive polysiloxane urethane acrylate oligomer

International Nuclear Information System (INIS)

Sun Fang; Zhang Nan; Du Hongguang; Jiang Shengling

2011-01-01

A UV-curable alkali-soluble polysiloxane urethane acrylate (APSUA) for solder mask was designed and synthesized in this work. The effect of composition of APSUA on physical and mechanical properties of UV curing APSUA materials including water resistance, volume shrinkage, hardness, tensile strength, elongation and heat resistance, was investigated in this paper. The results showed that reactive monomers with hydroxyl bonding could increase water absorption of the APSUA. The water absorption of the APSUA decreased with increasing crosslinking yields. The volume shrinkage of the APSUA decreased with increasing APSUA concentrations in the system and the volume shrinkage of investigated APSUA was lower than 6%. Multi-functional monomer and acrylate monomer with rigid structure could improve hardness of APSUA. When functionality of reactive monomer increased the heat resistance of APSUA could enhanced. The APSUA possesses excellent compatibility with most of acrylate monomers. (authors)

Time stamp technique using a nuclear emulsion multi-stage shifter for gamma-ray telescope

International Nuclear Information System (INIS)

Takahashi, Satoru; Aoki, Shigeki; Rokujo, Hiroki; Hamada, Kaname; Komatsu, Masahiro; Morishima, Kunihiro; Nakamura, Mitsuhiro; Nakano, Toshiyuki; Niwa, Kimio; Sato, Osamu; Yoshioka, Teppei; Kodama, Koichi

2010-01-01

Nuclear emulsion has a potential use as a gamma-ray telescope with high angular resolution. For this application it is necessary to know the time when each track was recorded in the emulsion. In previous experiments using nuclear emulsion, various efforts were used to associate time to nuclear emulsion tracks and to improve the time resolution. Using a high speed readout system for nuclear emulsion together with a clock-based multi-stage emulsion shifter, we invented a technique to give a time-stamp to emulsion tracks and greatly improve the time resolution. A test experiment with a 2-stage shifter was used to demonstrate the principle of multi-stage shifting, and we achieved a time resolution 1.5 s for 12.1 h (about 1 part in 29 000) with the time stamp reliability 97% and the time stamp efficiency 98%. This multi-stage shifter can achieve the time resolution required for a gamma-ray telescope and can also be applied to another cosmic ray observations and accelerator experiments using nuclear emulsion.

Preparation and physicochemical properties of surfactant-free emulsions using electrolytic-reduction ion water containing lithium magnesium sodium silicate.

Science.gov (United States)

Okajima, Masahiro; Wada, Yuko; Hosoya, Takashi; Hino, Fumio; Kitahara, Yoshiyasu; Shimokawa, Ken-ichi; Ishii, Fumiyoshi

2013-04-01

Surfactant-free emulsions by adding jojoba oil, squalane, olive oil, or glyceryl trioctanoate (medium chain fatty acid triglycerides, MCT) to electrolytic-reduction ion water containing lithium magnesium sodium silicate (GE-100) were prepared, and their physiochemical properties (thixotropy, zeta potential, and mean particle diameter) were evaluated. At an oil concentration of 10%, the zeta potential was ‒22.3 ‒ ‒26.8 mV, showing no marked differences among the emulsions of various types of oil, but the mean particle diameters in the olive oil emulsion (327 nm) and MCT emulsion (295 nm) were smaller than those in the other oil emulsions (452-471 nm). In addition, measurement of the hysteresis loop area of each type of emulsion revealed extremely high thixotropy of the emulsion containing MCT at a low concentration and the olive emulsion. Based on these results, since surfactants and antiseptic agents markedly damage sensitive skin tissue such as that with atopic dermatitis, surfactant- and antiseptic-free emulsions are expected to be new bases for drugs for external use.

Boosting the bioavailability of hydrophobic nutrients, vitamins, and nutraceuticals in natural products using excipient emulsions.

Science.gov (United States)

McClements, David Julian; Saliva-Trujillo, Laura; Zhang, Ruojie; Zhang, Zipei; Zou, Liqiang; Yao, Mingfei; Xiao, Hang

2016-10-01

Many highly hydrophobic bioactives, such as non-polar nutrients, nutraceuticals, and vitamins, have a relatively low or variable oral bioavailability. The poor bioavailability profile of these bioactives may be due to limited bioaccessibility, poor absorption, and/or chemical transformation within the gastrointestinal tract (GIT). The bioavailability of hydrophobic bioactives can be improved using specially designed oil-in-water emulsions consisting of lipid droplets dispersed within an aqueous phase. The bioactives may be isolated from their natural environment and then incorporated into the lipid phase of emulsion-based delivery systems. Alternatively, the bioactives may be left in their natural environment (e.g., fruits or vegetables), and then ingested with emulsion-based excipient systems. An excipient emulsion may have no inherent health benefits itself, but it boosts the biological activity of bioactive ingredients co-ingested with it by altering their bioaccessibility, absorption, and/or chemical transformation. This review discusses the design and fabrication of excipient emulsions, and gives some examples of recent research that demonstrates their potential efficacy for improving the bioavailability of hydrophobic bioactives. The concept of excipient emulsions could be used to formulate emulsion-based food products (such as excipient sauces, dressings, dips, creams, or yogurts) specifically designed to increase the bioavailability of bioactive agents in natural foods, such as fruits and vegetables. Copyright © 2015 Elsevier Ltd. All rights reserved.

The influence of polishing techniques on pre-polymerized CAD\\CAM acrylic resin denture bases.

Science.gov (United States)

Alammari, Manal Rahma

2017-10-01

Lately, computer-aided design and computer-aided manufacturing (CAD/CAM) has broadly been successfully employed in dentistry. The CAD/CAM systems have recently become commercially available for fabrication of complete dentures, and are considered as an alternative technique to conventionally processed acrylic resin bases. However, they have not yet been fully investigated. The purpose of this study was to inspect the effects of mechanical polishing and chemical polishing on the surface roughness (Ra) and contact angle (wettability) of heat-cured, auto-cured and CAD/CAM denture base acrylic resins. This study was conducted at the Advanced Dental Research Laboratory Center of King Abdulaziz University from March to June 2017. Three denture base materials were selected: heat cure poly-methylmethacrylate resin, thermoplastic (polyamide resin) and (CAD\\CAM) denture base resin. Sixty specimens were prepared and divided into three groups, twenty in each. Each group was divided according to the polishing techniques into (Mech P) and (Chem P), ten specimens in each; surface roughness and wettability were investigated. Data were analyzed by SPSS version 22, using one-way ANOVA and Pearson coefficient. One-way analysis of variance (ANOVA) and post hoc tests were used for comparing the surface roughness values between three groups which revealed a statistical significant difference between them (p 1 CAD\\CAM denture base material (group III) showed the least mean values (1.08±0.23, 1.39±0.31, Mech P and Chem P respectively). CAD/CAM showed the least contact angle in both polishing methods, which were statistically significant at 5% level (p=0.034 and pCAD\\CAM denture base resin with superior smooth surface compared to chemical polishing. Mechanical polishing is considered the best effective polishing technique. CAD/CAM denture base material should be considered as the material of choice for complete denture construction in the near future, especially for older dental

Residual monomer content determination in some acrylic denture base materials and possibilities of its reduction

Directory of Open Access Journals (Sweden)

Kostić Milena

2009-01-01

Full Text Available Background/Aim. Polymethyl methacrylate is used for producing a denture basis. It is a material made by the polymerization process of methyl methacrylate. Despite of the polymerization type, there is a certain amount of free methyl methacrylate (residual monomer incorporated in the denture, which can cause irritation of the oral mucosa. The aim of this study was to determine the amount of residual monomer in four different denture base acrylic resins by liquid chromatography and the possibility of its reduction. Methods. After the polymerization, a postpolymerization treatment was performed in three different ways: in boiling water for thirty minutes, with 500 W microwaves for three minutes and in steam bath at 22º C for one to thirty days. Results. The obtained results showed that the amount of residual monomer is significantly higher in cold polymerizing acrylates (9.1-11%. The amount of residual monomer after hot polymerization was in the tolerance range (0.59- 0.86%. Conclusion. The obtained results denote a low content of residual monomer in the samples which have undergone postpolymerization treatment. A lower percent of residual monomer is established in samples undergone a hot polymerization.

Emulsion properties of sunflower (Helianthus annuus) proteins

NARCIS (Netherlands)

Gonzalez-Perez, S.; Koningsveld, van G.A.; Vereijken, J.M.; Merck, K.B.; Gruppen, H.; Voragen, A.G.J.

2005-01-01

Emulsions were made with sunflower protein isolate (SI), helianthinin, and sunflower albumins (SFAs). Emulsion formation and stabilization were studied as a function of pH and ionic strength and after heat treatment of the proteins. The emulsions were characterized with respect to average droplet

The Effect of Reactives Diluents to the Physical Properties of Acrylated Palm Oil Based Polyurethane Coatings

Directory of Open Access Journals (Sweden)

Onn Munirah

2016-01-01

Full Text Available The development of polyurethane with hydroxyl access in a molecule leads to a new alternative of low toxicity green product. Palm oil is one of the major commodities in Malaysia. The potential of palm oil to be used as coatings raw material such as alkyd is limited due to low unsaturated side on fatty acid chains. To overcome this limitation, palm oil was modified through transesterification process to produce polyol. Acrylated isocyanate (urethane oligomer was then grafted onto polyol to produce polyurethane with vinylic ends. The polyurethane was formulated with different cross-linkers (reactive diluents and cured under UV radiation. The effect of three different diluents; monoacrylate, diacrylate and triacrylate on the properties of cured polymer were studied in this research. Fourier Transform Infrared (FTIR, Hydroxyl Value Titration, Gel Content, and Volatile Organic Compound (VOC were used for characterization. Physical testing performed were Pencil Hardness and Pull-Off Adhesion test. Novel palm oil-based polyurethane coatings have been found to have good properties with mono acrylate functionality.

Tuning Amphiphilicity of Particles for Controllable Pickering Emulsion

Directory of Open Access Journals (Sweden)

Zhen Wang

2016-11-01

Full Text Available Pickering emulsions with the use of particles as emulsifiers have been extensively used in scientific research and industrial production due to their edge in biocompatibility and stability compared with traditional emulsions. The control over Pickering emulsion stability and type plays a significant role in these applications. Among the present methods to build controllable Pickering emulsions, tuning the amphiphilicity of particles is comparatively effective and has attracted enormous attention. In this review, we highlight some recent advances in tuning the amphiphilicity of particles for controlling the stability and type of Pickering emulsions. The amphiphilicity of three types of particles including rigid particles, soft particles, and Janus particles are tailored by means of different mechanisms and discussed here in detail. The stabilization-destabilization interconversion and phase inversion of Pickering emulsions have been successfully achieved by changing the surface properties of these particles. This article provides a comprehensive review of controllable Pickering emulsions, which is expected to stimulate inspiration for designing and preparing novel Pickering emulsions, and ultimately directing the preparation of functional materials.

Biocompatibility of acrylic resin after being soaked in sodium hypochlorite

Directory of Open Access Journals (Sweden)

Nike Hendrijatini

2009-06-01

Full Text Available Background: Acrylic resin as basic material for denture will stay on oral mucosa for a very long time. The polymerization of acrylic resin can be performed by conventional method and microwave, both produce different residual monomer at different toxicity. Acrylic resin can absorb solution, porous and possibly absorb disinfectantt as well, that may have toxic reaction with the tissue. Sodium Hypochlorite as removable denture disinfectant can be expected to be biocompatible to human body. The problem is how biocompatible acrylic resin which has been processed by conventional method and microwave method after being soaked in sodium hypochlorite solution. Purpose: The aim of this study was to understand in vitro biocompatibility of acrylic resin which has polimerated by conventional method and microwave after being soaked in sodium hypochlorite using tissue culture. Methods: Four groups of acrylic resin plate were produced, the first group was acrylic resin plate with microwave polymeration and soaked in sodium hypochlorite, the second group was acrylic resin plate with microwave polymeration but not soaked, the thirdwas one with conventional method and soaked and the last group was one with conventional method but not soaked, and in 1 control group. Each group consists of 7 plates. Biocompatibility test was performed in-vitro on each material using fibroblast tissue culture (BHK-21 cell-line. Result: The percentage between living cells and dead cells from materials which was given acrylic plate was wounted. The data was analyzed statistically with T test. Conclusion: The average value of living cells is higher in acrylic resin poimerization using microwave method compared to conventional method, in both soaked and non soaked (by sodium hypochlorite group. This means that sodium hypochlorite 0.5% was biocompatible to the mouth mucosa as removable denture disinfectant for 10 minutes soaking and washing afterwards.

Electrochromatography on acrylate-based monolith in cyclic olefin copolymer microchip: an attractive technology.

Science.gov (United States)

Ladner, Y; Cretier, G; Faure, K

2015-01-01

Electrochromatography (EC) on a porous monolithic stationary phase prepared within the channels of a microsystem is an attractive alternative for on-chip separation. It combines the separation mechanisms of electrophoresis and liquid chromatography. Moreover, the porous polymer monolithic materials have become popular as stationary phase due to the ease and rapidity of fabrication via free radical photopolymerization. Here, we describe a hexyl acrylate (HA)-based porous monolith which is simultaneously in situ synthesized and anchored to the inner walls of the channel of a cyclic olefin copolymer (COC) device in only 2 min. The baseline separation of a mixture of neurotransmitters including six amino acids and two catecholamines is realized.

Oxidative stability of 70% fish oil‐in‐water emulsions: Impact of emulsifiers and pH

DEFF Research Database (Denmark)

Horn, Anna Frisenfeldt; Nielsen, Nina Skall; Andersen, Ulf

2011-01-01

The objective of this study was to evaluate the protective effects of five different emulsifiers on lipid oxidation in 70% fish oil‐in‐water emulsions to be used as delivery systems for long chain polyunsaturated omega‐3 fatty acids to foods. The emulsifiers were either phospholipid (PL) based......‐in‐water emulsions prepared with whey protein isolate, sodium caseinate, milk phospholipids, or soy lecithin. The emulsions can be used as delivery systems for fish oil to foods. However, only emulsions prepared with proteins at high pH offered advantages with respect to better oxidative stability during storage...... compared to neat fish oil. Thus, when fish oil is added to a food product in a delivery emulsion, the type of emulsion used should be carefully considered....

Simulation of 20-year deterioration of acrylic IOLs using severe accelerated deterioration tests.

Science.gov (United States)

Kawai, Kenji; Hayakawa, Kenji; Suzuki, Takahiro

2012-09-20

To investigate IOL deterioration by conducting severe accelerated deterioration testing of acrylic IOLs. Department of Ophthalmology, Tokai University School of Medicine Methods: Severe accelerated deterioration tests performed on 7 types of acrylic IOLs simulated 20 years of deterioration. IOLs were placed in a screw tube bottle containing ultra-pure water and kept in an oven (100°C) for 115 days. Deterioration was determined based the outer appearance of the IOL in water and under air-dried conditions using an optical microscope. For accelerated deterioration of polymeric material, the elapse of 115 days was considered to be equivalent to 20 years based on the Arrhenius equation. All of the IOLs in the hydrophobic acrylic group except for AU6 showed glistening-like opacity. The entire optical sections of MA60BM and SA60AT became yellowish white in color. Hydrophilic acrylic IOL HP60M showed no opacity at any of the time points examined. Our data based on accelerated testing showed differences in water content to play a major role in transparency. There were differences in opacity among manufacturers. The method we have used for determining the relative time of IOL deterioration might not represent the exact clinical setting, but the appearance of the materials would presumably be very similar to that seen in patients.

Destabilization of emulsions by natural minerals.

Science.gov (United States)

Yuan, Songhu; Tong, Man; Wu, Gaoming

2011-09-15

This study developed a novel method to destabilize emulsions and recycle oils, particularly for emulsified wastewater treatment. Natural minerals were used as demulsifying agents, two kinds of emulsions collected from medical and steel industry were treated. The addition of natural minerals, including artificial zeolite, natural zeolite, diatomite, bentonite and natural soil, could effectively destabilize both emulsions at pH 1 and 60 °C. Over 90% of chemical oxygen demand (COD) can be removed after treatment. Medical emulsion can be even destabilized by artificial zeolite at ambient temperature. The mechanism for emulsion destabilization by minerals was suggested as the decreased electrostatic repulsion at low pH, the enhanced gathering of oil microdroplets at elevated temperature, and the further decreased surface potential by the addition of minerals. Both flocculation and coalescence were enhanced by the addition of minerals at low pH and elevated temperature. Copyright © 2011 Elsevier B.V. All rights reserved.

Investigation of Acrylic Acid at High Pressure using Neutron Diffraction

DEFF Research Database (Denmark)

Johnston, Blair F.; Marshall, William G.; Parsons, Simon

2014-01-01

This article details the exploration of perdeuterated acrylic acid at high pressure using neutron diffraction. The structural changes that occur in acrylic acid-d4 are followed via diffraction and rationalised using the Pixel method. Acrylic acid undergoes a reconstructive phase transition to a new...

Microemulsion systems applied to breakdown petroleum emulsions

Energy Technology Data Exchange (ETDEWEB)

Neuma de Castro Dantas, Tereza; Avelino Dantas Neto, Afonso; Ferreira Moura, Everlane [Deptos de Quimica e Eng. Quimica, Universidade Federal do Rio Grande do Norte, Campus Universitario s/n, 59072.970, Natal/RN Campinas (Brazil)

2001-12-29

Microemulsion systems obtained using commercial surfactants with demulsifier and emulsion prevention properties have been employed to break down Brazilian crude water-in-oil (W/O) emulsions. These crude oils were supplied by the Brazilian oil company-PETROBRAS-and were characterized by the different Balance sheet of Sediment and Water (BSW) values of 48%, 36%, and 32%. The microemulsion systems formed in this study were composed of an aqueous phase (HCl 5.2% solution); an oil phase (toluene); a cosurfactant/surfactant (C/S) phase (isopropyl alcohol (C)/surfactants (S) with a ratio C/S of 9.0). The microemulsion efficiency to break down oil emulsions was evaluated by a direct contact method between the microemulsions and crude (W/O) emulsions. The Scheffe net statistical planning for mixtures was used to relate the component mass fractions to the relative breakdown of petroleum emulsions. The best composition of the microemulsion system for the complete breakdown of oil emulsions with high BSW values had the lowest C/S phase percentage.

Characteristics of Nano-emulsion for Cold Thermal Storage

Science.gov (United States)

Fumoto, Koji; Kawaji, Masahiro; Kawanami, Tsuyoshi

Phase change emulsion (PCE) is novel kind of heat storage and heat transfer fluids. It has characteristics as follows; greater apparent specific heat and higher heat transfer abilities in the phase change temperature range than conventional single phase heat transfer fluid. In this paper, a phase change emulsion, which has droplet diameter distribution of nanometer, were prepared. The Nano-emulsion was formed by low energy emulsification methods, as known the phase inversion temperature (PIT) method. Physical properties, such as viscosity, diameter and its distribution of emulsion were investigated. Especially, the relationships between preparation method and the concentration of surfactant have been discussed in detail. The results show that the viscosity of the Nano-emulsion is lower than the micro-emulsion, which was made by same mixing ratio of surfactant and concentration of phase change material. In addition, the Nano-emulsion clarified that stability was higher than microemulsions.

Effect of Grafted Hydroquinone on the Acid-Base Properties of Poly(acrylic acid in the Presence of Copper (II

Directory of Open Access Journals (Sweden)

Nabila Bensacia

2015-01-01

Full Text Available Potentiometric titration of poly(acrylic acid and hydroquinone-functionalized poly(acrylic acid was conducted in the presence of copper (II. The effects of hydroquinone functionalizing and copper (II complexing on the potentiometric titration of poly(acrylic acid were studied in an ionic environment and in its absence. Henderson-Hasselbalch equation was applied to assess its validity for this titration. Coordination number and the stability constants of the copper- (II-complexed polymers were determined, and results showed the formation of mostly monodentate and bidentate copper- (II-polymer complexes.

Chemo-enzymatic synthesis route to poly(glucosyl-acrylates) using glucosidase from almonds

NARCIS (Netherlands)

Kloosterman, Wouter M. J.; Roest, Steven; Priatna, Siti R.; Stavila, Erythrina; Loos, Katja

2014-01-01

Novel types of glucosyl-acrylate monomers are obtained by beta-glucosidase from almond catalyzed glycosidation reaction. The saccharide-acrylate monomers were synthesized by reaction of D-glucose with hydroxyl functional acrylates: 2-hydroxyethyl acrylate (2-HEA), 2-hydroxyethyl methacrylate

Poly(alkyl acrylate) nonparticles

International Nuclear Information System (INIS)

Kreuter, J.

1985-01-01

This study deals with the preparation of poly(alkyl acrylic) and poly(alkyl cyanocrylic) nanoparticles. Nonoparticles are solid colloidal particles, consisting of macromolecular materials in which drugs or biologically active materials are dissolved, entrapped, and encapsulated, and/or to which the active substance is adsorbed or attached. Poly(alkyl acrylic) nanoparticles are much more slowly biodegradable than poly(alkyl cyanoacrylate) nanoparticles, and are thus more suitable for drug delivery purposes. Poly(methyl methacrylate) is the material of choice for the use of nanoparticles as an adjuvant for vaccines and are produced by emulsifier-free polymerization in aqueous media. The polymerization, which can be initiated with gamma rays or with potassium peroxodisulfate, is described

Preparation and Surface Sizing Application of Sizing Agent Based on Collagen from Leather Waste

Directory of Open Access Journals (Sweden)

Xuechuan Wang

2015-09-01

Full Text Available Collagen extracted from leather waste was modified with maleic anhydride. Then, using ammonium persulfate as an initiator, by pre-modifying collagen reacted with styrene and ethyl acrylate monomers, a vinyl-grafted collagen sizing agent (VGCSA for paper was prepared. Before the experiment, the performance of VGCSA was tested and VGCSA emulsion was applied to the surface sizing of the corrugated paper. Effects of the amount of VGCSA, the compound proportion of VGCSA, and starch and styrene-acrylic emulsion were studied relative to paper properties. The morphological changes of the paper before and after sizing were characterized by SEM. It was found that the collagen reacted with styrene and ethyl acrylate monomers. Through the grafting of vinyl and collagen, the crystallinity and thermal stability of VGCSA increased. The structure of VGCSA was spherical with a uniform size, and the average particle size was approximately 350 to 400 nm. After being sized, the surface fibers of paper became smooth and orderly. The optimal sizing of VGCSA was 8 g/m2. The optimal proportion of VGCSA with starch was 4:6, and the optimal proportion of VGCSA with SAE was 2:8. The research indicates that collagen extracted from leather waste could be used as a biomaterial, and environmental and economic benefits could be created as well.

Proton Linear Energy Transfer measurement using Emulsion Cloud Chamber

Energy Technology Data Exchange (ETDEWEB)

Shin, Jae-ik [Proton Therapy Center, National Cancer Center (Korea, Republic of); Division of Heavy Ion Clinical Research, Korea Institute of Radiological & Medical Sciences (KIRAMS), Seoul (Korea, Republic of); Park, Seyjoon [Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University, School of Medicine, Seoul (Korea, Republic of); Kim, Haksoo; Kim, Meyoung [Proton Therapy Center, National Cancer Center (Korea, Republic of); Jeong, Chiyoung [Department of Radiation Oncology, Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Cho, Sungkoo [Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University, School of Medicine, Seoul (Korea, Republic of); Lim, Young Kyung; Shin, Dongho [Proton Therapy Center, National Cancer Center (Korea, Republic of); Lee, Se Byeong, E-mail: sblee@ncc.re.kr [Proton Therapy Center, National Cancer Center (Korea, Republic of); Morishima, Kunihiro; Naganawa, Naotaka; Sato, Osamu [Department of Physics, Nagoya University, Nagoya (Japan); Kwak, Jungwon [Department of Radiation Oncology, Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Kim, Sung Hyun [Center for Underground Physics, Institute for Basic Science (IBS), Daejeon (Korea, Republic of); Cho, Jung Sook [Department of refinement education, Dongseo University, Busan (Korea, Republic of); Ahn, Jung Keun [Department of Physics, Korea University, Seoul (Korea, Republic of); Kim, Ji Hyun; Yoon, Chun Sil [Gyeongsang National University, Jinju (Korea, Republic of); Incerti, Sebastien [CNRS, IN2P3, CENBG, UMR 5797, F-33170 Gradignan (France); Université Bordeaux 1, CENBG, UMR 5797, F-33170 Gradignan (France)

2015-04-15

This study proposes to determine the correlation between the Volume Pulse Height (VPH) measured by nuclear emulsion and Linear Energy Transfer (LET) calculated by Monte Carlo simulation based on Geant4. The nuclear emulsion was irradiated at the National Cancer Center (NCC) with a therapeutic proton beam and was installed at 5.2 m distance from the beam nozzle structure with various thicknesses of water-equivalent material (PMMA) blocks to position with specific positions along the Bragg curve. After the beam exposure and development of the emulsion films, the films were scanned by S-UTS developed in Nagoya University. The proton tracks in the scanned films were reconstructed using the ‘NETSCAN’ method. Through this procedure, the VPH can be derived from each reconstructed proton track at each position along the Bragg curve. The VPH value indicates the magnitude of energy loss in proton track. By comparison with the simulation results obtained using Geant4, we found the correlation between the LET calculated by Monte Carlo simulation and the VPH measured by the nuclear emulsion.

Proton Linear Energy Transfer measurement using Emulsion Cloud Chamber

International Nuclear Information System (INIS)

Shin, Jae-ik; Park, Seyjoon; Kim, Haksoo; Kim, Meyoung; Jeong, Chiyoung; Cho, Sungkoo; Lim, Young Kyung; Shin, Dongho; Lee, Se Byeong; Morishima, Kunihiro; Naganawa, Naotaka; Sato, Osamu; Kwak, Jungwon; Kim, Sung Hyun; Cho, Jung Sook; Ahn, Jung Keun; Kim, Ji Hyun; Yoon, Chun Sil; Incerti, Sebastien

2015-01-01

This study proposes to determine the correlation between the Volume Pulse Height (VPH) measured by nuclear emulsion and Linear Energy Transfer (LET) calculated by Monte Carlo simulation based on Geant4. The nuclear emulsion was irradiated at the National Cancer Center (NCC) with a therapeutic proton beam and was installed at 5.2 m distance from the beam nozzle structure with various thicknesses of water-equivalent material (PMMA) blocks to position with specific positions along the Bragg curve. After the beam exposure and development of the emulsion films, the films were scanned by S-UTS developed in Nagoya University. The proton tracks in the scanned films were reconstructed using the ‘NETSCAN’ method. Through this procedure, the VPH can be derived from each reconstructed proton track at each position along the Bragg curve. The VPH value indicates the magnitude of energy loss in proton track. By comparison with the simulation results obtained using Geant4, we found the correlation between the LET calculated by Monte Carlo simulation and the VPH measured by the nuclear emulsion

Proton Linear Energy Transfer measurement using Emulsion Cloud Chamber

Science.gov (United States)

Shin, Jae-ik; Park, Seyjoon; Kim, Haksoo; Kim, Meyoung; Jeong, Chiyoung; Cho, Sungkoo; Lim, Young Kyung; Shin, Dongho; Lee, Se Byeong; Morishima, Kunihiro; Naganawa, Naotaka; Sato, Osamu; Kwak, Jungwon; Kim, Sung Hyun; Cho, Jung Sook; Ahn, Jung Keun; Kim, Ji Hyun; Yoon, Chun Sil; Incerti, Sebastien

2015-04-01

This study proposes to determine the correlation between the Volume Pulse Height (VPH) measured by nuclear emulsion and Linear Energy Transfer (LET) calculated by Monte Carlo simulation based on Geant4. The nuclear emulsion was irradiated at the National Cancer Center (NCC) with a therapeutic proton beam and was installed at 5.2 m distance from the beam nozzle structure with various thicknesses of water-equivalent material (PMMA) blocks to position with specific positions along the Bragg curve. After the beam exposure and development of the emulsion films, the films were scanned by S-UTS developed in Nagoya University. The proton tracks in the scanned films were reconstructed using the 'NETSCAN' method. Through this procedure, the VPH can be derived from each reconstructed proton track at each position along the Bragg curve. The VPH value indicates the magnitude of energy loss in proton track. By comparison with the simulation results obtained using Geant4, we found the correlation between the LET calculated by Monte Carlo simulation and the VPH measured by the nuclear emulsion.

Methacrylate and acrylate allergy in dental personnel.

Science.gov (United States)

Aalto-Korte, Kristiina; Alanko, Kristiina; Kuuliala, Outi; Jolanki, Riitta

2007-11-01

Methacrylates are important allergens in dentistry. The study aimed to analyse patch test reactivity to 36 acrylic monomers in dental personnel in relation to exposure. We reviewed the test files at the Finnish Institute of Occupational Health from 1994 to 2006 for allergic reactions to acrylic monomers in dental personnel and analysed the clinical records of the sensitized patients. 32 patients had allergic reactions to acrylic monomers: 15 dental nurses, 9 dentists, and 8 dental technicians. The dentists and dental nurses were most commonly exposed to 2-hydroxyethyl methacrylate (2-HEMA), triethyleneglycol dimethacrylate (TREGDMA), and 2,2-bis[4-(2-hydroxy-3-methacryloxypropoxy) phenyl]propane (bis-GMA). 8 dentists and 12 dental nurses were allergic to 2-HEMA. The remaining dentist was positive to bis-GMA and other epoxy acrylates. The remaining 3 dental nurses reacted to diethyleneglycol diacrylate (DEGDA) or triethyleneglycol diacrylate (TREGDA), but not to monofunctional and multifunctional methacrylates. Our dental technicians were mainly exposed and sensitized to methyl methacrylate (MMA) and ethyleneglycol dimethacrylate (EGDMA). 1 technician reacted only to 2-HEMA, and another to ethyl methacrylate (EMA) and ethyl acrylate (EA). 2-HEMA was the most important allergen in dentists and dental nurses, and MMA and EGDMA in dental technicians. Reactions to bis-GMA, DEGDA, TREGDA, EMA and EA were relevant in some patients.

Preparation and Properties of Cassava Starch-based Wood Adhesives

Directory of Open Access Journals (Sweden)

Qing Xu

2016-06-01

Full Text Available A biodegradable, environmentally friendly starch-based wood adhesive with cassava starch as a raw material and butyl acrylate (BA as a co-monomer was synthesized. Results revealed that this cassava starch-based wood adhesive (SWA was more stable than corn starch-based wood adhesive, and its bonding performance was close to that of commercial PVAc emulsion, even after 90 days of storage. Further analysis found that the improved stability of the adhesive could be attributed to its low minimum film forming temperature (MFFT and glass transition temperature (Tg of cassava starch. Moreover, the amount of total volatile organic compounds (TVOCs emitted by the cassava starch-based wood adhesive were much lower than the Chinese national standard control criteria. Therefore, cassava SWA might be a potential alternative to traditional petrochemical-based wood adhesives.

Integrated, Continuous Emulsion Creamer.

Science.gov (United States)

Cochrane, Wesley G; Hackler, Amber L; Cavett, Valerie J; Price, Alexander K; Paegel, Brian M

2017-12-19

Automated and reproducible sample handling is a key requirement for high-throughput compound screening and currently demands heavy reliance on expensive robotics in screening centers. Integrated droplet microfluidic screening processors are poised to replace robotic automation by miniaturizing biochemical reactions to the droplet scale. These processors must generate, incubate, and sort droplets for continuous droplet screening, passively handling millions of droplets with complete uniformity, especially during the key step of sample incubation. Here, we disclose an integrated microfluidic emulsion creamer that packs ("creams") assay droplets by draining away excess oil through microfabricated drain channels. The drained oil coflows with creamed emulsion and then reintroduces the oil to disperse the droplets at the circuit terminus for analysis. Creamed emulsion assay incubation time dispersion was 1.7%, 3-fold less than other reported incubators. The integrated, continuous emulsion creamer (ICEcreamer) was used to miniaturize and optimize measurements of various enzymatic activities (phosphodiesterase, kinase, bacterial translation) under multiple- and single-turnover conditions. Combining the ICEcreamer with current integrated microfluidic DNA-encoded library bead processors eliminates potentially cumbersome instrumentation engineering challenges and is compatible with assays of diverse target class activities commonly investigated in drug discovery.

Extending temporary storage capacity with emulsion breakers

International Nuclear Information System (INIS)

Buist, I.; Guarino, A.; DeVitis, D.; Nolan, K.; Lewis, A.; Smith, B.; Lane, J.

2002-01-01

The use of emulsion breakers injected into an oil spill recovery system was examined in both laboratory testing and at the OHMSETT test facility. The tests were designed to assess the injection/mixing/settling regimes needed for optimum water-removal performance from a meso-stable water-in-oil emulsion with an oil spill demulsifier. Different types of injection locations and mixing technologies were examined, including skimmer heads, cargo lines, tank inlets, as well as static in-line and mechanical technologies. During laboratory testing, water-in-oil emulsions and free water was pumped through various lengths of piping loops, an in-line mixer and 8 settling tanks. Following the injection of a demulsifier, the fluid was decanted to observe the emulsion breaking. At the OHMSETT test facility, a Desmi Terminator skimmer recovered the same emulsion from a polluted water surface. Different slick thicknesses, wave heights and recovery rates were used. A demulsifier was also injected into the recovered fluid which was allowed to separate in recovery tanks. The demulsifier efficiency was then measured. It was determined that the demulsifier significantly reduced the volume of water in the recovery tanks and the water content of the remaining emulsion. If free water content was greater than 60 per cent, then the effect of the surfactant was greatly reduced. If no free water was present, the level of turbulence was insufficient to promote emulsion breaking. More than 33 per cent free water content is needed to reduce the bulk viscosity of the fluid and to promote emulsion breaking. The degree of emulsion breaking also increased with increasing mixing energy. 10 refs., 5 tabs., 8 figs

Heat-cured acrylic resin versus light-activated resin: a patient, professional and technician-based evaluation of mandibular implant-supported overdentures.

Science.gov (United States)

Asal, S A; Al-AlShiekh, H M

2017-12-01

Although light-activated resins (Eclipse) have been reported to possess superior physical and mechanical properties compared with the heat-cured acrylic resins (Lucitone-199), a few studies have compared overdentures with a locator attachment constructed from heat-cured acrylic resins with those constructed from light-activated resins. This clinical study was designed to compare the performance of a mandibular implant-supported overdenture constructed from a heat-cured acrylic resin (Lucitone-199) with that of an overdenture constructed from a light-activated resin (Eclipse). Ten participants received two identical mandibular implant-retained overdentures (Lucitone-199 and Eclipse) opposing one maxillary denture in a random order. Each mandibular overdenture was delivered and worn for 6 months, and two weeks of rest was advised between wears to minimize any carryover effects. Three questionnaires were devised. The first questionnaire (patient evaluation) focused on evaluating different aspects of the denture and overall satisfaction. The second questionnaire (professional dentist evaluation) was based on a clinical evaluation of soft tissues, complications, and the applied technique. The third questionnaire (technician evaluation) involved ranking the different manufacturing steps of the denture and overall preferences. The obtained data was statistically analyzed using an independent sample t-test and the Wilcoxon rank-sum test. The clinician and technician preferred the Eclipse dentures because of their technical aspects, whereas the patients preferred the Lucitone-199 dentures for their aesthetic properties. Implant-supported overdentures constructed from a heat-cured acrylic resin showed superior aesthetics and had a better odor compared with those constructed from a light-cured resin.

On the transport of emulsions in porous media

Energy Technology Data Exchange (ETDEWEB)

Cortis, Andrea; Ghezzehei, Teamrat A.

2007-06-27

Emulsions appear in many subsurface applications includingbioremediation, surfactant-enhanced remediation, and enhancedoil-recovery. Modeling emulsion transport in porous media is particularlychallenging because the rheological and physical properties of emulsionsare different from averages of the components. Current modelingapproaches are based on filtration theories, which are not suited toadequately address the pore-scale permeability fluctuations and reductionof absolute permeability that are often encountered during emulsiontransport. In this communication, we introduce a continuous time randomwalk based alternative approach that captures these unique features ofemulsion transport. Calculations based on the proposed approach resultedin excellent match with experimental observations of emulsionbreakthrough from the literature. Specifically, the new approach explainsthe slow late-time tailing behavior that could not be fitted using thestandard approach. The theory presented in this paper also provides animportant stepping stone toward a generalizedself-consistent modeling ofmultiphase flow.

Emulsion Polymerization of Tung Oil-Based Latexes with Asolectin as a Biorenewable Surfactant

Directory of Open Access Journals (Sweden)

Ashley Johns

2016-11-01

Full Text Available Bio-based vesicles, with potential application in drug delivery and/or catalyst encapsulation, have been prepared by the free radical emulsion co-polymerization of tung oil, divinylbenzene (DVB, n-butyl methacrylate (BMA, and asolectin in a xylene/water mixture. The free radical polymerization was initiated by di-tert-butyl peroxide (DTBP at 100 °C in a convection oven. Molecular weights of approximately 11,000 Da were measured by Matrix-assisted Laser Desorption/Ionization-Time of Flight (Maldi-TOF for tung oil-asolectin copolymers, verifying that significant polymerization occurs under the cure conditions employed. The cure of the co-monomer mixture employed in this work was monitored by Dielectric Analysis (DEA, while changes in the Raman spectrum of all co-monomers before and after the cure, along with differential scanning calorimetry (DSC analysis, have been used to verify the need of a post-cure step and completion of the polymerization reaction. Scanning Transmission Electron Microscopy (STEM images of the emulsion after polymerization indicate that vesicles were formed, and vesicle size distribution of samples prepared with different amounts of tung oil were determined using a Zetasizer.

Emulsion sheet doublets as interface trackers for the OPERA experiment

CERN Document Server

Anokhina, A.; Ariga, A.; Arrabito, L.; Autiero, D.; Badertscher, A.; Bay, F.; Greggio, F.Bersani; Bertolin, A.; Besnier, M.; Bick, D.; Bozza, C.; Brugiere, T.; Brugnera, R.; Brunetti, G.; Buontempo, S.; Carrara, E.; Cazes, A.; Chaussard, L.; Chernyavsky, M.; Chiarella, V.; Chon-Sen, N.; Chukanov, A.; Consiglio, L.; Cozzi, M.; Cuha, V.; Dal Corso, F.; D'Amato, G.; D'Ambrosio, N.; De Lellis, G.; Declais, Y.; De Serio, M.; Di Capua, F.; Di Ferdinando, D.; Di Giovanni, A.; Di Marco, N.; Di Troia, C.; Dmitrievski, S.; Dominjon, A.; Dracos, Marcos; Duchesneau, D.; Dusini, S.; Ebert, J.; Egorov, O.; Enikeev, R.; Ereditato, Antonio; Esposito, L.S.; Favier, J.; Felici, G.; Ferber, T.; Fini, R.; Frekers, D.; Fukuda, T.; Galkin, V.I.; Galkin, V.A.; Garfagnini, A.; Giacomelli, G.; Giorgini, M.; Goellnitz, C.; Goldberg, J.; Golubkov, D.; Gornushkin, Y.; Grella, G.; Grianti, F.; Guler, M.; Gusev, G.; Gustavino, C.; Hagner, Caren; Hara, T.; Hierholzer, M.; Hiramatsu, S.; Hoshino, Kaoru; Ieva, M.; Jakovcic, K.; Janicsko Csathy, J.; Janutta, B.; Jollet, C.; Juget, F.; Kawai, T.; Kazuyama, M.; Kim, S.H.; Knuesel, J.; Kodama, K.; Komatsu, M.; Kose, U.; Kreslo, I.; Laktineh, I.; Lazzaro, C.; Lenkeit, J.; Ljubicic, A.; Longhin, Andrea; Lutter, G.; Manai, K.; Mandrioli, G.; Marotta, A.; Marteau, J.; Matsuo, T.; Matsuoka, H.; Mauri, N.; Meisel, F.; Meregaglia, A.; Messina, M.; Migliozzi, P.; Mikado, S.; Miyamoto, S.; Monacelli, Piero; Morishima, Kunihiro; Moser, U.; Muciaccia, Maria Teresa; Naganawa, N.; Naka, T.; Nakamura, M.; Nakamura, T.; Nakano, T.; Nikitina, V.; Niwa, K.; Nonoyama, Y.; Ogawa, S.; Osedlo, V.; Ossetski, D.; Paoloni, A.; Park, B.D.; Park, I.G.; Pastore, A.; Patrizii, L.; Pennacchio, E.; Pessard, H.; Pilipenko, V.; Pistillo, C.; Polukhina, N.; Pozzato, M.; Pretzl, Klaus P.; Publichenko, P.; Pupilli, F.; Roganova, T.; Rosa, G.; Rostovtseva, I.; Rubbia, A.; Russo, A.; Ryazhskaya, O.; Ryzhikov, D.; Sato, O.; Sato, Y.; Saveliev, V.; Sazhina, G.; Schembri, A.; Scotto Lavina, L.; Shibuya, H.; Simone, S.; Sioli, Max; Sirignano, C.; Sirri, G.; Song, J.S.; Spinetti, M.; Stanco, L.; Starkov, N.; Stipcevic, M.; Strauss, T.; Strolin, Paolo Emilio; Sugonyaev, V.; Taira, Y.; Takahashi, S.; Tenti, M.; Terranova, F.; Tezuka, I.; Tioukov, V.; Tolun, P.; Tsarev, V.; Tufanli, S.; Ushida, N.; Vilain, P.; Vladimirov, M.; Votano, L.; Vuilleumier, J.L.; Wilquet, G.; Wonsak, B.; Wurtz, J.; Yoon, C.S.; Yoshida, J.; Zaitsev, Y.; Zemskova, S.; Zghiche, Amina; Zimmermann, R.

2008-01-01

New methods for efficient and unambiguous interconnection between electronic counters and target units based on nuclear photographic emulsion films have been developed. The application to the OPERA experiment, that aims at detecting oscillations between mu neutrino and tau neutrino in the CNGS neutrino beam, is reported in this paper. In order to reduce background due to latent tracks collected before installation in the detector, on-site large-scale treatments of the emulsions ("refreshing") have been applied. Changeable Sheet (CSd) packages, each made of a doublet of emulsion films, have been designed, assembled and coupled to the OPERA target units ("ECC bricks"). A device has been built to print X-ray spots for accurate interconnection both within the CSd and between the CSd and the related ECC brick. Sample emulsion films have been extensively scanned with state-of-the-art automated optical microscopes. Efficient track-matching and powerful background rejection have been achieved in tests with electronic...

Cleaning fluid emulsions

Energy Technology Data Exchange (ETDEWEB)

Prikryl, J; Kotyza, R; Krulikovsky, J; Mjartan, V; Valisova, I

1981-09-15

Composition of cleaning fluid emulsion are presented for drilling small diameter wells in clay soils, at high drill bit rotation velocity. The emulsions have lubricating properties and the abilty to improve stability of the drilled soil. The given fluids have a high fatty acid content with 12-24 carbon atoms in a single molecule, with a predominance of resinous acids 1-5% in mass, and having been emulsified in water or clay suspension without additives, or in a clay suspension with high-molecular polymer additives (glycobate cellulose compounds and/or polysaccharides, and/or their derivatives) in an amount of 0.1-3% per mass; thinning agents - huminite or lignite compounds in the amount of 0.01 to 0.5% in mass; weighting material - barite or lime 0.01 to 50% per mass; medium stabilizers - organic poly-electrolyte with polyacrylate in the amount of 0.05 to 2% in mass, or alkaline chloride/alkaline-ground metals 1-10% per mass. A cleaning emulsion fluid was prepared in the laboratory according to the given method. Add 3 kg tall oil to a solution of 1 kg K/sub 2/CO/sub 3/ per 100 l of water. Dynamic viscosity was equal to 1.4 x 10-/sup 3/ Pa/s. When drilling in compacted clay soils, when the emulsions require improved stability, it is necessary to add the maximum amount of tall oil whose molecules are absorbed by the clay soil and increase its durability.

Multivariate optimization of the determination of zinc in diesel oil employing a novel extraction strategy based on emulsion breaking

International Nuclear Information System (INIS)

Cassella, Ricardo J.; Brum, Daniel M.; Lima, Claudio F.; Caldas, Luiz Fernando S.; Paula, Carlos Eduardo R. de

2011-01-01

This paper describes the extraction/pre-concentration of Zn from diesel oil and its determination by Flame Atomic Absorption Spectrometry (FAAS), proposed as a novel approach for these kinds of analyses and the multivariate optimization of the proposed procedure. The extraction of Zn is based on the emulsification of an aqueous solution containing Triton X-114 and HNO 3 with diesel oil samples followed by breaking of the emulsion by heating. The aqueous phase obtained after the emulsion breaking was collected and used for Zn quantification by FAAS. The methodology was optimized using a Doehlert design and the system variables were the concentrations of surfactant and HNO 3 in the solution employed in the emulsification and the temperature used in the emulsion breaking. The ratio between absorbance and the time required to break the emulsions was taken as response. Two sets of experiments, using different emulsifier agents, were run: the first one using Triton X-100 and the second one using Triton X-114. At optimized conditions, the emulsions were prepared by mixing 10 mL of diesel oil with 2 mL of a solution containing 5% w/v of Triton X-114 and 15% v/v of HNO 3 and broken by heating at 80 o C. The proposed analytical procedure was applied in the analysis of six real samples of diesel oil and a recovery test was carried out by spiking the samples with known amounts of Zn (25 and 50 μg L -1 ), added as organometallic oiled standard. Recovery percentages achieved in this test were between 92 and 109%.

Multivariate optimization of the determination of zinc in diesel oil employing a novel extraction strategy based on emulsion breaking

Energy Technology Data Exchange (ETDEWEB)

Cassella, Ricardo J., E-mail: cassella@vm.uff.br [Departamento de Quimica Analitica, Universidade Federal Fluminense, Outeiro de Sao Joao Batista s/n, Centro, Niteroi, RJ 24020-141 (Brazil); Brum, Daniel M.; Lima, Claudio F. [Departamento de Quimica, Universidade Federal de Vicosa, Av. Peter Henry Rolfs s/n, Vicosa, MG 36570-000 (Brazil); Caldas, Luiz Fernando S.; Paula, Carlos Eduardo R. de [Departamento de Quimica Analitica, Universidade Federal Fluminense, Outeiro de Sao Joao Batista s/n, Centro, Niteroi, RJ 24020-141 (Brazil)

2011-03-25

This paper describes the extraction/pre-concentration of Zn from diesel oil and its determination by Flame Atomic Absorption Spectrometry (FAAS), proposed as a novel approach for these kinds of analyses and the multivariate optimization of the proposed procedure. The extraction of Zn is based on the emulsification of an aqueous solution containing Triton X-114 and HNO{sub 3} with diesel oil samples followed by breaking of the emulsion by heating. The aqueous phase obtained after the emulsion breaking was collected and used for Zn quantification by FAAS. The methodology was optimized using a Doehlert design and the system variables were the concentrations of surfactant and HNO{sub 3} in the solution employed in the emulsification and the temperature used in the emulsion breaking. The ratio between absorbance and the time required to break the emulsions was taken as response. Two sets of experiments, using different emulsifier agents, were run: the first one using Triton X-100 and the second one using Triton X-114. At optimized conditions, the emulsions were prepared by mixing 10 mL of diesel oil with 2 mL of a solution containing 5% w/v of Triton X-114 and 15% v/v of HNO{sub 3} and broken by heating at 80 {sup o}C. The proposed analytical procedure was applied in the analysis of six real samples of diesel oil and a recovery test was carried out by spiking the samples with known amounts of Zn (25 and 50 {mu}g L{sup -1}), added as organometallic oiled standard. Recovery percentages achieved in this test were between 92 and 109%.

New UV-curable acrylated polyester prepolymers from palm oil based products

International Nuclear Information System (INIS)

Mohd Azam Ali; Ooi, T.L.; Salmiah Ahmad; Umaru, S.I.; Mohd Ishak, Z.A.

1999-01-01

Acrylated polyester prepolymers (PEPP-1 and PEPP-2) were synthesized from palm oil and its products. UV-curing and characteristic properties of UV-cured films of synthesized polyester resins were studied. The characteristic properties studied include pendulum hardness, gel content, FT-IR analysis, tensile strength and elongation at break. The materials have good potential for the production of radiation curable coating applications

Report: Potential of nano-emulsions as phytochemical delivery system for food preservation.

Science.gov (United States)

Mahmood, Zaffar; Jahangir, Muhammad; Liaquat, Muhammad; Shah, Syed Wasim Ahmad; Khan, Muhammad Mumtaz; Stanley, Roger; D'Arcy, Bruce

2017-11-01

Nature is a rich source of bioactive phytochemicals. These plant based compounds have rich scope as antioxidants, antimicrobial compounds and food preservatives and so for long time to be used in meat, fruits, vegetables and processed food items, either as added preservative or as coating material in various food applications, but the major limitation is their limited solubility in a food grade medium. Nano-emulsion is a best choice as a medium having vast area of application. The major advantage of nano-emulsion would be the solubility of a vast group of compounds, due to the presence of water and lipid phases. In this way, nano-emulsions can be proved to be the most suitable candidate as phytochemical delivery system for food preservation. In present article, the use of phytochemicals as potent food preservatives has been reviewed, in context of solubility of phytochemicals in nano-emulsion and applications of food grade nano-emulsions to food systems.

Laboratory effectiveness testing of water-in-oil emulsion breakers

International Nuclear Information System (INIS)

Fingas, M.F.; Fieldhouse, B.; Bier, I.; Conrod, D.; Tennyson, E.

1995-01-01

The physics and chemistry of water-in-oil emulsions dominate the development of effectiveness tests. Emulsions are variable in stability--this variability is largely dependent on oil type and degree of weathering. These factors complicate the development of a test. Emulsions which have low stability will apparently break easily with chemical emulsion breakers. Broken emulsions will form a foam-like material, called rag, which retains water which is not part of the stable emulsions. Analytical methods used to determine the final stability of the broken or unbroken emulsion were evaluated. Measurements of water content and viscosity measurements show correlation to emulsion stability. Viscosity provides a more reliable measure of emulsion stability but water content measurements are more convenient and are largely used in this study. Twelve tests were developed in the past. Two testing methods have been developed to a usable stage. These tests are described and data using them provided. The effects of mixing time, agent amount, settling time and mixing energy on effectiveness results are presented

Emulsions: the cutting edge of development in blasting agent technology - a method for economic comparison

Energy Technology Data Exchange (ETDEWEB)

Ayat, M.G.; Allen, S.G.

1988-03-01

This work examines the history and development of blasting agents beginning with ANFO in the 1950's and concluding with a specific look at the 1980's blasting technology: the emulsion. Properties of emulsions and Emulsion Blend Explosive Systems are compared with ANFO and a method of comparing their costs, useful for comparing any two explosives, is developed. Based on this comparison, the Emulsion Blend Explosive System is determined superior to ANFO on the basis of cost per unit of overburden broken. 4 refs.

A general computation model based on inverse analysis principle used for rheological analysis of W/O rapeseed and soybean oil emulsions

Science.gov (United States)

Vintila, Iuliana; Gavrus, Adinel

2017-10-01

The present research paper proposes the validation of a rigorous computation model used as a numerical tool to identify rheological behavior of complex emulsions W/O. Considering a three-dimensional description of a general viscoplastic flow it is detailed the thermo-mechanical equations used to identify fluid or soft material's rheological laws starting from global experimental measurements. Analyses are conducted for complex emulsions W/O having generally a Bingham behavior using the shear stress - strain rate dependency based on a power law and using an improved analytical model. Experimental results are investigated in case of rheological behavior for crude and refined rapeseed/soybean oils and four types of corresponding W/O emulsions using different physical-chemical composition. The rheological behavior model was correlated with the thermo-mechanical analysis of a plane-plane rheometer, oil content, chemical composition, particle size and emulsifier's concentration. The parameters of rheological laws describing the industrial oils and the W/O concentrated emulsions behavior were computed from estimated shear stresses using a non-linear regression technique and from experimental torques using the inverse analysis tool designed by A. Gavrus (1992-2000).

Water-in-oil emulsions results of formation studies and applicability to oil spill modelling

International Nuclear Information System (INIS)

Fingas, Merv; Fieldhouse, Ben; Mullin, Joe

1999-01-01

has not been accurately defined. Emulsions from many oils have been characterised. This information is used to describe how this process can be accurately modelled and what information gaps exist for complete description of the physical process. The modelling of emulsions is reviewed. A new modelling scheme based on the new physical findings, is suggested. (Author)

Microfluidic methods to study emulsion formation

OpenAIRE

Muijlwijk, Kelly

2017-01-01

Emulsions are dispersions of one liquid in another that are commonly used in various products, and methods such as high-pressure homogenisers and colloid mills are used to form emulsions. The size and size distribution of emulsion droplets are important for the final product properties and thus need to be controlled. Rapid coalescence of droplets during emulsification increases droplet size and widens the size distribution, and therefore needs to be prevented. To increase stability of emulsio...

Contrast agent based on nano-emulsion for targeted biomedical imaging

International Nuclear Information System (INIS)

Attia, Mohamed

2016-01-01

poly(maleic anhydride-alt-1-octadecene) (PMAO). The in vitro results and in vivo evaluations were completely coherent approving that the neutral charged NPs are less toxic compared to the negatively charged ones that were highly up-taken in the cells causing stress to the cells and thereby affecting the toxicity. As a result they are different in biodistribution and pharmacokinetics. In this context, for the first time, we were able to functionalize the nano-emulsion droplets with ligand molecules by covalent bonds. Likewise we designed nano-droplets and coated by silica shell ended by amino groups and then followed by formation of amide bonds with grafting to dye ligand model (coumarin blue dye). The quantification of amino groups was performed by using spectroscopic and microscopic techniques, with a grafting efficiency as high as 41%. This process improves the targeting properties of such chemotherapeutic agents to the location of interest following active targeting mechanism (ligand receptor strategy). One of our achieved objectives was to engineer multifunctional polymer-based NPs encapsulating hydrophobic drug model as DDs and iron oxide NPs as a theranostic model. To conclude, novel contrast agents and delivering systems were synthesized with outstanding physicochemical characteristics and suitable for in vivo medium with high efficacy and low toxicity [fr

78 FR 55644 - Styrene, Copolymers with Acrylic Acid and/or Methacrylic Acid; Tolerance Exemption

Science.gov (United States)

2013-09-11

..., 3-sulfopropyl acrylate, 3-sulfopropyl methacrylate, hydroxypropyl methacrylate, hydroxypropyl acrylate, hydroxyethyl methacrylate, and/or hydroxyethyl acrylate; and its sodium, potassium, ammonium..., hydroxypropyl acrylate, hydroxyethyl methacrylate, and/or hydroxyethyl acrylate; and its sodium, potassium...

Synthesis of Highly Porous Poly(tert-butyl acrylate)-b-polysulfone-b-poly(tert-butyl acrylate) Asymmetric Membranes

KAUST Repository

Xie, Yihui; Moreno Chaparro, Nicolas; Calo, Victor M.; Cheng, Hong; Hong, Pei-Ying; Sougrat, Rachid; Behzad, Ali Reza; Tayouo Djinsu, Russell; Nunes, Suzana Pereira

2016-01-01

For the first time, self-assembly and non-solvent induced phase separation was applied to polysulfone-based linear block copolymers, reaching mechanical stability much higher than other block copolymers membranes used in this method, which were mainly based on polystyrene blocks. Poly(tert-butyl acrylate)-b-polysulfone-b-poly(tert-butyl acrylate) (PtBA30k-b-PSU14k-b-PtBA30k) with a low polydispersity of 1.4 was synthesized by combining step-growth condensation and RAFT polymerization. Various advanced electron microscopies revealed that PtBA30k-b-PSU14k-b-PtBA30k assembles into worm-like cylindrical micelles in DMAc and adopts a “flower-like” arrangement with the PSU central block forming the shell. Computational modeling described the mechanism of micelle formation and morphological transition. Asymmetric nanostructured membranes were obtained with a highly porous interconnected skin layer and a sublayer with finger-like macrovoids. Ultrafiltration tests confirmed a water permeance of 555 L m-2 h-1 bar-1 with molecular weight cut-off of 28 kg/mol. PtBA segments on the membrane surface were then hydrolyzed and complexed with metals, leading to cross-linking and enhancement of antibacterial capability.

Synthesis of Highly Porous Poly(tert-butyl acrylate)-b-polysulfone-b-poly(tert-butyl acrylate) Asymmetric Membranes

KAUST Repository

Xie, Yihui

2016-03-24

For the first time, self-assembly and non-solvent induced phase separation was applied to polysulfone-based linear block copolymers, reaching mechanical stability much higher than other block copolymers membranes used in this method, which were mainly based on polystyrene blocks. Poly(tert-butyl acrylate)-b-polysulfone-b-poly(tert-butyl acrylate) (PtBA30k-b-PSU14k-b-PtBA30k) with a low polydispersity of 1.4 was synthesized by combining step-growth condensation and RAFT polymerization. Various advanced electron microscopies revealed that PtBA30k-b-PSU14k-b-PtBA30k assembles into worm-like cylindrical micelles in DMAc and adopts a “flower-like” arrangement with the PSU central block forming the shell. Computational modeling described the mechanism of micelle formation and morphological transition. Asymmetric nanostructured membranes were obtained with a highly porous interconnected skin layer and a sublayer with finger-like macrovoids. Ultrafiltration tests confirmed a water permeance of 555 L m-2 h-1 bar-1 with molecular weight cut-off of 28 kg/mol. PtBA segments on the membrane surface were then hydrolyzed and complexed with metals, leading to cross-linking and enhancement of antibacterial capability.

The development of epoxidised palm oil acrylate (EPOLA) and its applications

Energy Technology Data Exchange (ETDEWEB)

Mahmood, Mohd Hilmi [Nuclear Energy Unit, Bangi, Selangor (Malaysia)

1994-12-31

The topics are discussed briefly. Acrylated palm oil is prepared through acrylation process, whereby, acrylic acid is introduced into oxirane group of the EPOP (epoxidised palm oil products), EPOLA (epoxidised palm oil products acrylate) was found curable when subjected to UV (ultrviolet) light giving soft coatings. EPOLA is used as radiation curable filler/sealer, radiation curable pressure sensitive adhesives and satisfactorily be coated on wood substrates (rubberwood parquets).

The development of epoxidised palm oil acrylate (EPOLA) and its applications

International Nuclear Information System (INIS)

Mohd Hilmi Mahmood

1993-01-01

The topics are discussed briefly. Acrylated palm oil is prepared through acrylation process, whereby, acrylic acid is introduced into oxirane group of the EPOP (epoxidised palm oil products), EPOLA (epoxidised palm oil products acrylate) was found curable when subjected to UV (ultrviolet) light giving soft coatings. EPOLA is used as radiation curable filler/sealer, radiation curable pressure sensitive adhesives and satisfactorily be coated on wood substrates (rubberwood parquets)

Boundary lubrication of stainless steel and CoCrMo alloy based on phosphorous and boron compounds in oil-in-water emulsion

International Nuclear Information System (INIS)

Yan, Jincan; Zeng, Xiangqiong; Ren, Tianhui; Heide, Emile van der

2014-01-01

Highlights: • The boundary lubrication behaviour of three O/W emulsions was investigated. • The interactions between O/W emulsions and CoCrMo surfaces were studied. • Three different additives containing P and B were added in the emulsions. • The tribologcial performance of oil lubricant and emulsion was compared. • The friction profile of emulsion shows three stages due to spreading and plate-out. - Abstract: Emulsion lubrication is widely used in metal forming operations and has potential applications in the biomedical field, yet the emulsion lubrication mechanism is not well understood. This work explores the possibilities of three different oil-in-water (O/W) emulsions containing dibutyl octadecylphosphoramidate (DBOP), 6-octadecyl-1,3,6,2-dioxazaborocan-2-ol calcium salt (ODOC) and 2-(4-dodecylphenoxy)-6-octadecyl-1,3,6,2-dioxazaborocane (DOB) to generate boundary films on stainless steel AISI 316 and CoCrMo alloy surfaces. Experimental results show lower friction values for the emulsions in combination with CoCrMo compared to AISI 316. The different performance of the additives is related to the composition of the adsorption and reaction film on the interacting surfaces, which was shown to be dependent on the active elements and molecular structure of the additives. The friction profile of the emulsions indicates that the emulsion appears to be broken during the rubbing process, then the additives adsorb onto the metal surface to form protecting boundary layers. The XPS analysis shows that for boundary lubrication conditions, the additive molecules in the emulsion first adsorb on the metal surface after the droplet is broken, and then decompose and react with the metal surface during the rubbing process to form stable lubricating films on the rubbed surfaces

Boundary lubrication of stainless steel and CoCrMo alloy based on phosphorous and boron compounds in oil-in-water emulsion

Energy Technology Data Exchange (ETDEWEB)

Yan, Jincan [Laboratory for Surface Technology and Tribology, University of Twente (Netherlands); School of Chemistry and Chemical Engineering, Key Laboratory for Thin Film and Microfabrication, Shanghai Jiao Tong University (China); Zeng, Xiangqiong, E-mail: X.Zeng@utwente.nl [Laboratory for Surface Technology and Tribology, University of Twente (Netherlands); School of Chemistry and Chemical Engineering, Key Laboratory for Thin Film and Microfabrication, Shanghai Jiao Tong University (China); Ren, Tianhui [School of Chemistry and Chemical Engineering, Key Laboratory for Thin Film and Microfabrication, Shanghai Jiao Tong University (China); Heide, Emile van der [Laboratory for Surface Technology and Tribology, University of Twente (Netherlands); TNO (Netherlands)

2014-10-01

Highlights: • The boundary lubrication behaviour of three O/W emulsions was investigated. • The interactions between O/W emulsions and CoCrMo surfaces were studied. • Three different additives containing P and B were added in the emulsions. • The tribologcial performance of oil lubricant and emulsion was compared. • The friction profile of emulsion shows three stages due to spreading and plate-out. - Abstract: Emulsion lubrication is widely used in metal forming operations and has potential applications in the biomedical field, yet the emulsion lubrication mechanism is not well understood. This work explores the possibilities of three different oil-in-water (O/W) emulsions containing dibutyl octadecylphosphoramidate (DBOP), 6-octadecyl-1,3,6,2-dioxazaborocan-2-ol calcium salt (ODOC) and 2-(4-dodecylphenoxy)-6-octadecyl-1,3,6,2-dioxazaborocane (DOB) to generate boundary films on stainless steel AISI 316 and CoCrMo alloy surfaces. Experimental results show lower friction values for the emulsions in combination with CoCrMo compared to AISI 316. The different performance of the additives is related to the composition of the adsorption and reaction film on the interacting surfaces, which was shown to be dependent on the active elements and molecular structure of the additives. The friction profile of the emulsions indicates that the emulsion appears to be broken during the rubbing process, then the additives adsorb onto the metal surface to form protecting boundary layers. The XPS analysis shows that for boundary lubrication conditions, the additive molecules in the emulsion first adsorb on the metal surface after the droplet is broken, and then decompose and react with the metal surface during the rubbing process to form stable lubricating films on the rubbed surfaces.

Synthesis of acrylated palm oil nanoparticles using microemulsion polymerization initiated by gamma ray

International Nuclear Information System (INIS)

Rida Tajau; Wan Md Zin Wan Yunus; Khairul Zaman Mohd Dahlan; Mohd Hilmi Mahmood; Kamaruddin Hashim; Sim, Flora; Sharila Muhd Faizal

2010-01-01

The use of microemulsion in the development of nanoparticle based on acrylated palm oil product is demonstrated. The microemulsion polymerization was initiated by gamma ray for synthesizing crosslinked nanoparticle. Polymerization of acrylated palm oil in three-component ionic microemulsions was prepared with sodium dodecyl sulphate (SDS) and water. The resulted nanoparticle, before and after initiated by gamma ray, were evaluated in terms of particle diameter, surface charge and molecular structure. Type and concentration of surfactants, monomer concentration, radiation dose and time of storage strongly affected the size, charge and size stability of the particles. For the development of new microscopic polymer acrylated palm oil can be synthesized into nano sized particle and it has potential to be developed in medical devices and controlled-drug-release-applications. (author)

Enhanced fish oil-in-water emulsions enabled by rapeseed lecithins obtained under different processing conditions.

Science.gov (United States)

Li, Jingbo; Pedersen, Jacob Nedergaard; Anankanbil, Sampson; Guo, Zheng

2018-10-30

It is hypothesized that rapeseed lecithins may have different emulsifying and antioxidant properties in delivering fish oil compared to soy lecithin based on previous studies. The results showed that in vitro antioxidant activities of rapeseed lecithins were stronger than those of soy lecithin. Emulsions stabilized by rapeseed based lecithins and DATEM were stable over 3 months at 4 °C, whereas the creaming of emulsions containing soy lecithin started immediately after its preparation. Zeta-potential of rapeseed lecithins was higher than soy lecithin and DATEM, which partially contributed to the emulsion stability. Although the particle sizes of emulsions prepared by rapeseed lecithins increased after 14 days storage, no creaming was observed. Lipid oxidation as indicated by TBARS values suggested that DATEM was the most unfavorable, followed by soy lecithin. It is concluded that rapeseed lecithins are better than soy lecithin and DATEM in terms of emulsion stability and antioxidant capability, respectively. Copyright © 2018 Elsevier Ltd. All rights reserved.

Photochemistry of acrylates at 222 nm

International Nuclear Information System (INIS)

Knolle, Wolfgang; Naumov, Sergej; Madani, Mohamed; Sonntag, Clemens von

2005-01-01

Excimer lamps as monochromatic UV sources with an intense short-wavelength emission (especially KrCl * , 222 nm) allow a photoinitiator-free initiation of the acrylate polymerisation. Laser photolysis (KrCl * excimer laser, pulse width 20 ns, up to 5 mJ per pulse) gives rise to similar transient spectra (λ max ∼ 280 nm) for all acrylates studied. As the rather unspecific spectra do not allow conclusions as to the main reaction channel, a product study has been performed by GC-MS following steady-state photolysis of acrylate solutions in acetonitrile, methanol and n-hexane. Somewhat unexpected, α-cleavage seems to be a main reaction channel, and quantum chemical calculations show that such a reaction can occur from either the excited singlet state or the unrelaxed triplet state, but not from the relaxed triplet state that is observed spectroscopically. A reaction scheme accounting for the observed products is presented

Food emulsions as delivery systems for flavor compounds: A review.

Science.gov (United States)

Mao, Like; Roos, Yrjö H; Biliaderis, Costas G; Miao, Song

2017-10-13

Food flavor is an important attribute of quality food, and it largely determines consumer food preference. Many food products exist as emulsions or experience emulsification during processing, and therefore, a good understanding of flavor release from emulsions is essential to design food with desirable flavor characteristics. Emulsions are biphasic systems, where flavor compounds are partitioning into different phases, and the releases can be modulated through different ways. Emulsion ingredients, such as oils, emulsifiers, thickening agents, can interact with flavor compounds, thus modifying the thermodynamic behavior of flavor compounds. Emulsion structures, including droplet size and size distribution, viscosity, interface thickness, etc., can influence flavor component partition and their diffusion in the emulsions, resulting in different release kinetics. When emulsions are consumed in the mouth, both emulsion ingredients and structures undergo significant changes, resulting in different flavor perception. Special design of emulsion structures in the water phase, oil phase, and interface provides emulsions with great potential as delivery systems to control flavor release in wider applications. This review provides an overview of the current understanding of flavor release from emulsions, and how emulsions can behave as delivery systems for flavor compounds to better design novel food products with enhanced sensorial and nutritional attributes.

Cold in-place recycling using solventless emulsion - phase IV (emulsion qualification and long-term field performance).

Science.gov (United States)

2016-05-01

This report looks into how a successful Cold In-Place solventless emulsion behaves and how the emulsion : break test developed in Phase III of this project demonstrates that behavior. Modifications to the test have been : made to improve the consiste...

Effects of emulsion droplet sizes on the crystallisation of milk fat.

Science.gov (United States)

Truong, Tuyen; Bansal, Nidhi; Sharma, Ranjan; Palmer, Martin; Bhandari, Bhesh

2014-02-15

The crystallisation properties of milk fat emulsions containing dairy-based ingredients as functions of emulsion droplet size, cooling rate, and emulsifier type were investigated using a differential scanning calorimeter (DSC). Anhydrous milk fat and its fractions (stearin and olein) were emulsified with whey protein concentrate, sodium caseinate, and Tween80 by homogenisation to produce emulsions in various size ranges (0.13-3.10 μm). Particle size, cooling rate, and types of emulsifier all had an influence on the crystallisation properties of fat in the emulsions. In general, the crystallisation temperature of emulsified fats decreased with decreasing average droplet size and was of an exponent function of size, indicating that the influence of particle size on crystallisation temperature is more pronounced in the sub-micron range. This particle size effect was also verified by electron microscopy. Copyright © 2013 Elsevier Ltd. All rights reserved.

Storage stability of marine phospholipids emulsions

DEFF Research Database (Denmark)

Lu, Henna Fung Sieng; Nielsen, Nina Skall; Baron, Caroline Pascale

Marine phospholipids (MPL) are believed to provide more advantages than fish oil from the same source. They are considered to have a better bioavailability, a better resistance towards oxidation and a higher content of polyunsaturated fatty acids such as eicosapentaenoic (EPA) and docosahexaenoic...... acids (DHA) than oily triglycerides (fish oil). Therefore, the objective of this study is to explore the feasibility of using marine phospholipids emulsions as delivery system through investigation of the physical, oxidative and hydrolytic stability of MPL emulsions with or without addition of fish oil....... The effect of initial Peroxide Value, total lipids, phospholipids and antioxidants content on stability of MPL emulsions were studied. The physical stability was investigated through measurement of particle size distribution and creaming stability, which involve measurement of changes (%) in emulsion volume...

Synthesis and characterization of acrylated Parkia biglobosa medium oil alkyds

Directory of Open Access Journals (Sweden)

E.T. Akintayo

2004-12-01

Full Text Available Acrylated Parkia biglobosa medium oil alkyd prepared by the reaction between an acid containing acrylic copolymer and a monoglyceride followed by the addition of polyol and dibasic acid has been investigated for improved properties. The results revealed that acid functional acrylic copolymers containing maleic anhydride as a functional co-monomer can successfully be used to modify alkyd resins yielding acrylated resins with better drying, flexibility, scratch hardness, impact resistance and chemical resistance properties. However there exist optimum levels for modification of alkyds with such copolymers beyond which certain film properties are adversely affected.

Influence of pH value on microstructure of oil-in-water emulsions stabilized by chickpea protein flour.

Science.gov (United States)

Felix, Manuel; Isurralde, Nadia; Romero, Alberto; Guerrero, Antonio

2018-01-01

Food industry is highly interested in the development of healthier formulations of oil-in-water emulsions, stabilized by plant proteins instead of egg or milk proteins. These emulsions would avoid allergic issues or animal fat. Among other plant proteins, legumes are a cost-competitive product. This work evaluates the influence of pH value (2.5, 5.0 and 7.5) on emulsions stabilized by chickpea-based emulsions at two different protein concentration (2.0 and 4.0 wt%). Microstructure of chickpea-based emulsions is assessed by means of backscattering, droplet size distributions and small amplitude oscillatory shear measurements. Visual appearances as well as confocal laser scanning microscopy images are obtained to provide useful information on the emulsions structure. Interestingly, results indicate that the pH value and protein concentration have a strong influence on emulsion microstructure and stability. Thus, the system which contains protein surfaces positively charged shows the highest viscoelastic properties, a good droplet size distribution profile and non-apparent destabilization phenomena. Interestingly, results also reveal the importance of rheological measurements in the prediction of protein interactions and emulsion stability since this technique is able to predict destabilization mechanisms sooner than other techniques such as backscattering or droplet size distribution measurements.

All-acrylic superelastomers: facile synthesis and exceptional mechanical behavior

Energy Technology Data Exchange (ETDEWEB)

Lu, Wei; Goodwin, Andrew; Wang, Yangyang; Yin, Panchao; Wang, Weiyu; Zhu, Jiahua; Wu, Ting; Lu, Xinyi; Hu, Bin; Hong, Kunlun; Kang, Nam-Goo; Mays, Jimmy (Tennessee-K); (ORNL)

2018-01-01

All-acrylic multigraft copolymers made by a facile synthesis procedure exhibit elongation at break >1700% and strain recovery behavior far exceeding those of commercial acrylic and styrenic triblock copolymers.

Biocompatible Metal-Oxide Nanoparticles: Nanotechnology Improvement of Conventional Prosthetic Acrylic Resins

Directory of Open Access Journals (Sweden)

Laura S. Acosta-Torres

2011-01-01

Full Text Available Nowadays, most products for dental restoration are produced from acrylic resins based on heat-cured Poly(Methyl MethAcrylate (PMMA. The addition of metal nanoparticles to organic materials is known to increase the surface hydrophobicity and to reduce adherence to biomolecules. This paper describes the use of nanostructured materials, TiO2 and Fe2O3, for simultaneously coloring and/or improving the antimicrobial properties of PMMA resins. Nanoparticles of metal oxides were included during suspension polymerization to produce hybrid metal oxides-alginate-containing PMMA. Metal oxide nanoparticles were characterized by dynamic light scattering, and X-ray diffraction. Physicochemical characterization of synthesized resins was assessed by a combination of spectroscopy, scanning electron microscopy, viscometry, porosity, and mechanical tests. Adherence of Candida albicans cells and cellular compatibility assays were performed to explore biocompatibility and microbial adhesion of standard and novel materials. Our results show that introduction of biocompatible metal nanoparticles is a suitable means for the improvement of conventional acrylic dental resins.

Bioaccessibility and Cellular Uptake of β-Carotene Encapsulated in Model O/W Emulsions: Influence of Initial Droplet Size and Emulsifiers

Directory of Open Access Journals (Sweden)

Wei Lu

2017-09-01

Full Text Available The effects of the initial emulsion structure (droplet size and emulsifier on the properties of β-carotene-loaded emulsions and the bioavailability of β-carotene after passing through simulated gastrointestinal tract (GIT digestion were investigated. Exposure to GIT significantly changed the droplet size, surface charge and composition of all emulsions, and these changes were dependent on their initial droplet size and the emulsifiers used. Whey protein isolate (WPI-stabilized emulsion showed the highest β-carotene bioaccessibility, while sodium caseinate (SCN-stabilized emulsion showed the highest cellular uptake of β-carotene. The bioavailability of emulsion-encapsulated β-carotene based on the results of bioaccessibility and cellular uptake showed the same order with the results of cellular uptake being SCN > TW80 > WPI. An inconsistency between the results of bioaccessibility and bioavailability was observed, indicating that the cellular uptake assay is necessary for a reliable evaluation of the bioavailability of emulsion-encapsulated compounds. The findings in this study contribute to a better understanding of the correlation between emulsion structure and the digestive fate of emulsion-encapsulated nutrients, which make it possible to achieve controlled or potential targeted delivery of nutrients by designing the structure of emulsion-based carriers.

Thermogravimetric analysis of the polymer acrylate-vinyl ether mixture cured by radiation

International Nuclear Information System (INIS)

Danu, Sugiarto

1998-01-01

An experiment on thermal stability of the polymer acrylate-vinyl ether mixture cured by radiation have been done using thermogravimetric analysis. Three kinds of acrylic oligomers i.e., epoxy acrylate, urethane acrylate, and polypropylene glycol diacrylate, and vinyl ether monomers i.e., triethylene glycol divinyl ether (DVE-3), 1,4-cyclohexane dimethanol divinyl ether (CHVE), and butanediol monovinyl ether (HBVE) were used in the experiment. Reaction was taken via radical and cationic polymerisation. In case of cationic polymerisation, diphenyliodonium hexafluorophosphate fotoinisiator was used in the formulation. Thermogravimetric analysis was conducted in a nitrogen atmosphere at a flow rate of 40 ml/minute with a constant heating rate 10 o C and evaluation range were done from 25 to 500 o C. The results of thermogravimetric analysis showed that acrylate and DVE-3 mixture produced the polymer films with higher thermal stability than the mixture of acrylate with CHVE or HBVE. The composition of acrylate-vinyl ether mixture and degree of unsaturation of vinyl ether monomers influenced the thermal stability of polymer. The mixture of epoxy acrylate-vinyl ether and polypropylene glycol diacrylate-vinyl ether have 1 initial decomposition temperature whereas the urethane acrylate-vinyl ether mixture has 2 initial decomposition temperatures. (authors)

Electron beam curing of acrylic oligomers

International Nuclear Information System (INIS)

Seto, J.; Arakawa, S.; Ishimoto, C.; Miyashita, M.; Nagai, T.; Noguchi, T.; Shibata, A.

1984-01-01

The electron-beam curing process of acrylic oligomers, with and without γ-Fe 2 O 3 pigment filler and blended linear polymer, was investigated in terms of molecular structure and reaction mechanism. The polymerized fraction of trimethylolpropane-triacrylate (TMPTA) oligomers increases with increasing total dose, and is independent of the dose rate. Since the reaction rate is linearly dependent on the dose rate, the reaction mechanism involves monomolecular termination. The reaction rate does not depend on the number of functional groups of the oligomer at low doses, but above 0.3 Mrad the rate is slower for oligomers of higher functionality. A gel is formed more readily upon curing of a polyfunctional than a monofunctional oligomer, especially at high conversion to polymer; the resulting loss of flexibility of the polymer chains slows the reaction. Decrease of the molecular weight per functional group results in lower conversion; this is also due to the loss of chain flexibility, which is indicated as well by a higher glass-transition temperature. Modification of the acrylate oligomers with urethane results in more effective cross-linking reactions because of the more rigid molecular chains. Addition of γ-Fe 2 O 3 pigment reduces the reaction rate very little, but has the effect of providing added structural integrity, as indicated by the decrease of solvent-extractable material and the improvement of anti-abrasion properties. However, the flexibility of the coating and its adhesion to a PET base film are diminished. To increase the flexibility, linear polyvinylchloride and/or polyurethane were added to the acrylic oligomers. Final conversion to polymer was nearly 100 percent, and a higher elastic modulus and better antiabrasion properties were realized

Emulsifier development for high-concentrated reverse emulsions

Directory of Open Access Journals (Sweden)

I.L. Kovalenko

2016-05-01

Full Text Available The reverse emulsions have found broad application in ore mining industry as matrixes of emulsion explosive substances and boring washing waters. The defining characteristic of reverse emulsions of industrial explosive substances is the high stability and immunity to crystallization. Aim: The aim of this work is to assess the mechanism of emulsifiers effect like SMO and some PIBSA-derivatives, that are most abundantly used in world practice, and also to develop an effective domestic emulsifier of reverse emulsions. Materials and methods: Using the semi-dynamic method with use of the reverse stalagmometer it was determined the decreasing in interfacial tension on “water / diesel fuel” border in the presence of 0.5 wt % sorbitan monooleate of various producers. Emulsions with use of the chosen emulsifiers using the dynamic mixer on the basis of monosolution of ammonium nitrate and diesel fuel have been produced. The emulsions have the following composition, wt %: ammonium nitrate – 76.8; water – 15.6; diesel fuel – 6.0; emulsifier – 1.6. Results: By the researches results of the interfacial tension “surfactant water / solution in diesel fuel”, the stability of emulsions using monosolution of ammonium nitrate and the IR spectrums of SMO of various producers it is established that presence in product of impurity of oleic acid, di- and trioleates leads to decreasing in interphase activity, increasing of emulsifier oil solubility and decreasing the resistance of emulsions to crystallization. On the basis of the spectral data analysis it is suggested about possibility of specific interaction on the mechanism of “spectral resonance” between emulsifiers of the PIBSA-MEA, LZX type and crystals nucleus of NH4NO3 ammonium nitrate in dispersed phase of emulsion. Amidation of vegetable oils by monoethanol amine is implemented at the reduced temperatures (90…100 °C. It was proved the availability mainly of fatty acids amides in product

Evaluation of the maladaptation of the test base in acrylic resin regarding the technique of preparation, place of measurement and storage time

Directory of Open Access Journals (Sweden)

Natália Pereira de OLIVEIRA

2018-02-01

Full Text Available Abstract Introduction The most used material for the preparation of the baseplates is the acrylic resin, but it can present distortions. Objective To evaluate preparation technique, region and storage time that presents less maladaptation of the base when made with self-cured acrylic resin. Material and method Models were created in gypsum type III simulating edentulous maxilla, as divided into 3 groups (n = 10: GC (control group thermopolymerizable acrylic resin; G1 - manual adaptation technique and G2 - drip technique. For the measurements, silicone by condensation of light consistency that was interposed between base and model was used. With a hydraulic press, 50 kg pressure was applied leading the base of the model. The obtained mold was measured in the palate, canine and molar regions with a digital caliper at the following times: immediately after the base polymerization, at 24, 48, 72, 96 hours and one week. The results were submitted to statistical analysis. Result G1 presented maladaptation of 0.43 mm ± 0.10, while G2 obtained 0.39 mm ± 0.11. The lowest maladaptation occurred in the CG. The palate region presented greater maladaptation (0.52 ± 0.07 and the canine region, the lowest (CD = 0.27 mm ± 0.07 and CE = 0.27 ± 0.09; There was no statistically significant difference for storage times. Conclusion G2 presented lower values than G1, with no statistically significant difference. The palate region presented greater maladaptation, followed by molars and canines. The bases continued to maladaptation the model after the immediate polymerization, with no statistically significant difference.

The effects of short term intravenous infusion of a soybean based lipid emulsion on some blood constituents in sheep: A preliminary study

Directory of Open Access Journals (Sweden)

Hamid Akbari

2014-04-01

Full Text Available To evaluate the effect of intravenous infusion of a soybean based lipid emulsion (Lipovenoes 10% on some blood constituents in sheep, a replicated 2 × 2 Latin square design experiment was conducted in four clinically healthy ewes. Lipid emulsion (LE group or normal saline (NS group was infused intravenously at a rate of 0.025 mL kg-1 per min for 6 hr and the concentrations of blood triglyceride, glucose, insulin, calcium, magnesium, phosphorous, sodium and potassium were measured before (baseline and then at timepoints 2, 4, 6, 12 and 24 hr after infusion. Compared to the baseline values and/or NS infusion, LE infusion resulted in a significant increase in the concentrations of triglyceride (p 0.05. In conclusion, intravenous infusion of Lipovenoes temporarily influenced some blood constituents. Increased triglyceride concentrations were associated with an increase in HOMA-IR values indicating a state of insulin resistance. No remarkable adverse effect was observed following LE infusion and lipid based emulsions can be safely used in ruminants not suffering from extensive lipid mobilization.

Chemistry and technology of emulsion polymerisation

NARCIS (Netherlands)

Herk, van A.M.

2005-01-01

Emulsion polymerisation produces high value polymers in a low cost, environmentally friendly process. The drive to develop environmentally benign production methods for polymers has resulted in widespread development and implementation of the emulsion polymerisation technique. In addition, when

A magnetic nanoparticle stabilized gas containing emulsion for multimodal imaging and triggered drug release.

Science.gov (United States)

Guo, Wei; Li, Diancheng; Zhu, Jia-an; Wei, Xiaohui; Men, Weiwei; Yin, Dazhi; Fan, Mingxia; Xu, Yuhong

2014-06-01

To develop a multimodal imaging guided and triggered drug delivery system based on a novel emulsion formulation composed of iron oxide nanoparticles, nanoscopic bubbles, and oil containing drugs. Iron oxide paramagnetic nanoparticles were synthesized and modified with surface conjugation of polyethylenimide (PEI) or Bovine Serum Albumin (BSA). Both particles were used to disperse and stabilize oil in water emulsions containing coumarin-6 as the model drug. Sulfur hexafluoride was introduced into the oil phase to form nanoscopic bubbles inside the emulsions. The resulted gas containing emulsions were evaluated for their magnetic resonance (MR) and ultrasound (US) imaging properties. The drug release profile triggered by ultrasound was also examined. We have successfully prepared the highly integrated multi-component emulsion system using the surface modified iron oxide nanoparticles to stabilize the interfaces. The resulted structure had distinctive MR and US imaging properties. Upon application of ultrasound waves, the gas containing emulsion would burst and encapsulated drug could be released. The integrated emulsion formulation was multifunctional with paramagnetic, sono-responsive and drug-carrying characteristics, which may have potential applications for disease diagnosis and imaging guided drug release.

Thermal stability and mechanism of decomposition of emulsion explosives in the presence of pyrite.

Science.gov (United States)

Xu, Zhi-Xiang; Wang, Qian; Fu, Xiao-Qi

2015-12-30

The reaction of emulsion explosives (ammonium nitrate) with pyrite was studied using techniques of TG-DTG-DTA. TG-DSC-MS was also used to analyze samples thermal decomposition process. When a mixture of pyrite and emulsion explosives was heated at a constant heating rate of 10K/min from room temperature to 350°C, exothermic reactions occurred at about 200°C. The essence of reaction between emulsion explosives and pyrite is the reaction between ammonium nitrate and pyrite. Emulsion explosives have excellent thermal stability but it does not mean it showed the same excellent thermal stability when pyrite was added. Package emulsion explosives were more suitable to use in pyrite shale than bulk emulsion explosives. The exothermic reaction was considered to take place between ammonium nitrate and pyrite where NO, NO2, NH3, SO2 and N2O gases were produced. Based on the analysis of the gaseous, a new overall reaction was proposed, which was thermodynamically favorable. The results have significant implication in the understanding of stability of emulsion explosives in reactive mining grounds containing pyrite minerals. Copyright © 2015 Elsevier B.V. All rights reserved.

Egg white powder-stabilised multiple (water-in-olive oil-in-water) emulsions as beef fat replacers in model system meat emulsions.

Science.gov (United States)

Öztürk, Burcu; Urgu, Müge; Serdaroğlu, Meltem

2017-05-01

Today, multiple emulsions are believed to have a considerable application potential in food industry. We aimed to investigate physical, chemical and textural quality characteristics of model system meat emulsions (MSME) in which beef fat (C) was totally replaced by 10% (E-10), 20% (E-20) or 30% (E-30) multiple emulsions (W 1 /O/W 2 ) prepared with olive oil and egg white powder (EWP). Incorporation of W 1 /O/W 2 emulsion resulted in reduced fat (from 11.54% to 4.01%), increased protein content (from 13.66% to 14.74%), and modified fatty acid composition, significantly increasing mono- and polyunsaturated fatty acid content and decreasing saturated fatty acid content. E-20 and E-30 samples had lower jelly and fat separation (5.77% and 5.25%) compared to C and E-10 (9.67% and 8.55%). W 1 /O/W 2 emulsion treatments had higher water-holding capacity (93.96-94.35%) than C samples (91.84%), and also showed the desired storage stability over time. Emulsion stability results showed that E-20 and E-30 samples had lower total expressible fluid (14.05% and 14.53%) and lower total expressible fat (5.06% and 5.33%) compared to C samples (19.13% and 6.09%). Increased concentrations of W 1 /O/W 2 emulsions led to alterations in colour and texture parameters. TBA values of samples were lower in W 1 /O/W 2 emulsion treatments than control treatment during 60 days of storage. Our results indicated that multiple emulsions prepared with olive oil and EWP had promising impacts on reducing fat, modifying the lipid composition and developing both technologically and oxidatively stable meat systems. These are the first findings concerning beef matrix fat replacement with multiple emulsions stabilised by EWP. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Long-term characteristics of nuclear emulsion

International Nuclear Information System (INIS)

Naganawa, N; Kuwabara, K

2010-01-01

Long-term characteristics of the nuclear emulsion so called 'OPERA film' used in the neutrino oscillation experiment, OPERA, has been studied for 8 years since its production or refreshing after it. In the results, it turned out to be excellent in sensitivity, amount of random noise, and refreshing characteristics. The retention capacity of latent image of tracks was also studied. The result will open the way to the recycling of 7,000,000 emulsion films which will remain not developed after 5 years of OPERA's run, and other long-term experiments with emulsion.

Long-term characteristics of nuclear emulsion

Science.gov (United States)

Naganawa, N.; Kuwabara, K.

2010-02-01

Long-term characteristics of the nuclear emulsion so called ``OPERA film'' used in the neutrino oscillation experiment, OPERA, has been studied for 8 years since its production or refreshing after it. In the results, it turned out to be excellent in sensitivity, amount of random noise, and refreshing characteristics. The retention capacity of latent image of tracks was also studied. The result will open the way to the recycling of 7,000,000 emulsion films which will remain not developed after 5 years of OPERA's run, and other long-term experiments with emulsion.

Oxidative Stability of Granola Bars Enriched with Multilayered Fish Oil Emulsion in the Presence of Novel Brown Seaweed Based Antioxidants

DEFF Research Database (Denmark)

Hermund, Ditte Baun; Karadaǧ, Ayşe; Andersen, Ulf

2016-01-01

as a barrier to the penetration and diffusion of molecular species that promote oxidation. The positive charge of oil droplets in the secondary emulsion may also inhibit iron-lipid interaction through electrostatic repulsion. Additional protection against lipid oxidation was obtained when fish oil emulsions......Fucus vesiculosus extracts that have both radical scavenging activity and metal chelating ability in vitro were used as natural antioxidant in granola bars enriched with fish oil emulsion by using primary and secondary emulsion systems stabilized by sodium caseinate alone and sodium caseinate...

Synergistic and antagonistic effects of plant and dairy protein blends on the physicochemical stability of lycopene-loaded emulsions

NARCIS (Netherlands)

Ho, Kacie K.H.Y.; Schroën, Karin; San Martín-González, M.F.; Berton-Carabin, Claire C.

2018-01-01

Whey-plant protein-based emulsions had high physicochemical stability. Whey and plant protein blend-based interfaces were viscoelastic while casein-based interfaces were relatively viscous. Whey-plant and plant-plant protein blends behaved synergistically leading to enhanced emulsion stability.

GLA-AF, an emulsion-free vaccine adjuvant for pandemic influenza.

Science.gov (United States)

Clegg, Christopher H; Roque, Richard; Perrone, Lucy A; Rininger, Joseph A; Bowen, Richard; Reed, Steven G

2014-01-01

The ongoing threat from Influenza necessitates the development of new vaccine and adjuvant technologies that can maximize vaccine immunogenicity, shorten production cycles, and increase global vaccine supply. Currently, the most successful adjuvants for Influenza vaccines are squalene-based oil-in-water emulsions. These adjuvants enhance seroprotective antibody titers to homologous and heterologous strains of virus, and augment a significant dose sparing activity that could improve vaccine manufacturing capacity. As an alternative to an emulsion, we tested a simple lipid-based aqueous formulation containing a synthetic TLR4 ligand (GLA-AF) for its ability to enhance protection against H5N1 infection. GLA-AF was very effective in adjuvanting recombinant H5 hemagglutinin antigen (rH5) in mice and was as potent as the stable emulsion, SE. Both adjuvants induced similar antibody titers using a sub-microgram dose of rH5, and both conferred complete protection against a highly pathogenic H5N1 challenge. However, GLA-AF was the superior adjuvant in ferrets. GLA-AF stimulated a broader antibody response than SE after both the prime and boost immunization with rH5, and ferrets were better protected against homologous and heterologous strains of H5N1 virus. Thus, GLA-AF is a potent emulsion-free adjuvant that warrants consideration for pandemic influenza vaccine development.

Comparison of lipid emulsions on antioxidant capacity in preterm infants receiving parenteral nutrition.

Science.gov (United States)

Köksal, Nilgün; Kavurt, Ahmet V; Cetinkaya, Merih; Ozarda, Yesim; Ozkan, Hilal

2011-08-01

Although a variety of different lipid emulsions with varying fatty acid contents have been developed, there are some concerns about the administration of these lipid emulsions because of potential adverse effects, including oxidative stress-related morbidity. The aim of the present study was to evaluate and compare the effects of the standard soybean oil-based and olive oil-based i.v. lipid emulsions (ILE) on oxidative stress, determined by total antioxidant capacity (TAC), and to investigate the safety of the use of these two emulsions in terms of biochemical indices. In this prospective study, premature infants were randomly assigned to two groups, each group consisting of 32 patients who received parenteral ILE of either 20% olive oil or 20% soybean oil. They were given ILE for 7 days and then were evaluated with regard to TAC. No statistically significant difference was observed between the groups in terms of routine biochemical parameters. TAC for both groups on day 7 was significantly lower compared with that on day 0. Although the decrease in TAC within 7 days of ILE administration was greater in the soybean group compared with that in the olive oil group, it was not statistically significant. Olive oil-based ILE exhibit similar antioxidant activity and can be used as an alternative to soybean oil-based ILE. TAC significantly decreased in infants following administration of either lipid emulsion, and premature infants tolerated either ILE well, both biochemically and clinically. © 2011 The Authors. Pediatrics International © 2011 Japan Pediatric Society.

Conversion of Lignocellulosic Biomass to Ethanol and Butyl Acrylate

Energy Technology Data Exchange (ETDEWEB)

Binder, Thomas [Archer Daniels Midland Company, Decatur, IL (United States); Erpelding, Michael [Archer Daniels Midland Company, Decatur, IL (United States); Schmid, Josef [Archer Daniels Midland Company, Decatur, IL (United States); Chin, Andrew [Archer Daniels Midland Company, Decatur, IL (United States); Sammons, Rhea [Archer Daniels Midland Company, Decatur, IL (United States); Rockafellow, Erin [Archer Daniels Midland Company, Decatur, IL (United States)

2015-04-10

Conversion of Lignocellulosic Biomass to Ethanol and Butyl Acrylate. The purpose of Archer Daniels Midlands Integrated Biorefinery (IBR) was to demonstrate a modified acetosolv process on corn stover. It would show the fractionation of crop residue to distinct fractions of cellulose, hemicellulose, and lignin. The cellulose and hemicellulose fractions would be further converted to ethanol as the primary product and a fraction of the sugars would be catalytically converted to acrylic acid, with butyl acrylate the final product. These primary steps have been demonstrated.

Evaluation of thermal conductivity of heat-cured acrylic resin mixed with A1203

OpenAIRE

Ebadian B.; Parkan MA.

2002-01-01

One of the most important characteristics of denture base is thermal conductivity. This property has a major role in secretions of salivary glands and their enzymes, taste of the food and gustatory response. Polymethyl methacrylate used in prosthodontics is relatively an insulator. Different materials such as metal fillers and ceramics have been used to solve this problem. The aim of this study was the evaluation of AI2O3 effect on thermal conductivity of heat-cured acrylic resin. Acrylic res...

The emulsifying and tribological properties of modified graphene oxide in oil-in-water emulsion

NARCIS (Netherlands)

Wu, Yinglei; Zeng, Xiangqiong; Ren, Tianhui; de Vries, Erik G.; van der Heide, Emile

2017-01-01

Graphene oxide (GO) was asymmetric chemically modified with myristyltrimethylammonium bromide (TTAB) to get modified graphene oxide (MGO). This MGO was used as an emulsifier and additive in oil-in-water emulsion. The emulsifying tests showed MGO greatly improved the stability of base emulsion and

UV-Curing of Nanoparticle Reinforced Acrylates

International Nuclear Information System (INIS)

Bauer, F.

2006-01-01

Polymer reinforcement by silica and alumina nanoparticles evidently yields improved surface hardness. Single mixing of nanoparticles into an acrylate formulations, however, leads to highly viscous solutions inappropriate for coating procedures. The incompatibility of inorganic fillers and organic polymers can be avoided by surface modification providing an interface between the two dissimilar materials. For example, vinyltrimethoxysilane (VTMO) can react via hydrolysis/condensation reactions with hydroxyl groups present on the inorganic surface and should bond via the polymerisation-active vinyl group to an acrylate resin through crosslinking reactions. Grafting reactions of surface OH groups and different trialkoxysilanes were studied by thermogravimetry, infrared, and multinuclear NMR spectroscopy. The copolymeri-zation of modified nanoparticles with the acrylate matrix has been investigated by 13 C NMR spectroscopy. UV curing under nitrogen inertization revealed a lower reactivity of vinyl groups of VTMO-modified silica compared to grafted methacryloxypropyl-trimethoxysilane (MEMO) which showed complete conversion of olefinic carbons (signals at 120 - 140 ppm). Under conditions of oxygen inhibition, the effect of the kind and the concentration of photoinitiator on the photopoly-merization reaction was studied. Compared to neat polyacrylate coatings the nanocomposite materials exhibit markedly improved properties, e.g., heat, scratch, and abrasion resistance. However, a much better abrasion resistance was obtained for coatings containing both silica nano-particles and corundum microparticles. In particular cases, radiation curing with 172 nm photons generated by Xe excimer was performed to obtain structured polymer surfaces, i.e., matting of the reinforced acrylate coatings

Nuclear emulsion and high-energy physics

International Nuclear Information System (INIS)

Sun Hancheng; Zhang Donghai

2008-01-01

The history of the development of nuclear emulsion and its applications in high-energy physics, from the discovery of pion to the discovery of tau neutrino, are briefly reviewed in this paper. A new stage of development of nuclear-emulsion technique is discussed

Flammability and thermal properties studies of nonwoven flax reinforced acrylic based polyester composites

Science.gov (United States)

Rasyid, M. F. Ahmad; Salim, M. S.; Akil, H. M.; Ishak, Z. A. Mohd.

2017-12-01

In the pursuit of green and more sustainable product, natural fibre reinforced composites originating from renewable resources has gained interest in recent years. These natural fibres exhibit good mechanical properties, low production costs, and good environmental properties. However, one of the disadvantages of natural fibre reinforced composites is their high flammability that limits their application in many fields. Within this research, the effect of sodium silicate on the flammability and thermal properties of flax reinforced acrylic based polyester composites has been investigated. Sodium silicate is applied as binder and flame retardant system in impregnation process of the natural flax fiber mats. The addition of sodium silicate significantly improved the flame retardant efficiency but reduced the degree of crosslinking of the composites.

The output kinetics of piroxicam from emulsion microcapsules based on high methylated pectin and lactoglobulin of whey in experiments vitro

International Nuclear Information System (INIS)

Goibova, Z.V.; Bobokalonov, D.T.; Usmanova, S.R.; Teshaev, Kh.I.; Mukhidinov, Z.K.

2015-01-01

Present article is devoted to output kinetics of piroxicam from emulsion microcapsules based on high methylated pectin and lactoglobulin of whey in experiments vitro. The dependence of piroxicam output on time at various mole ratio was studied.

Application of mathematical planning in production of filled emulsion rubbers

Science.gov (United States)

Pugacheva, I. N.; Molokanova, L. V.; Popova, L. V.; Repin, P. S.

2018-05-01

The applicability of mathematical planning of experiment in the field of chemistry and chemical engineering, in particular in the industrial production of synthetic rubbers, is considered in the article. Possibility of using secondary material resources, which are waste products of light industry, in the production of elastomeric compositions is studied. The method of obtaining a powdered cellulose additive from wastes containing cellulose fiber is described. The best way of introducing the obtained additive into elastomeric compositions based on the emulsion rubber is established. Optimal conditions for obtaining filled emulsion rubber with the help of a powdered cellulose additive were established basing on the mathematical planning of experiment.

Distribution of Tocopherols and Tocotrienols in Guinea Pig Tissues Following Parenteral Lipid Emulsion Infusion.

Science.gov (United States)

Xu, Zhidong; Harvey, Kevin A; Pavlina, Thomas M; Zaloga, Gary P; Siddiqui, Rafat A

2016-07-01

Tocopherols and tocotrienols possess vitamin E activity and function as the major lipid-soluble antioxidants in the human body. Commercial lipid emulsions are composed of different oils and supply different amounts of vitamin E. The objective of this study was to measure all 8 vitamin E homologs within 4 different commercial lipid emulsions and evaluate their distribution in guinea pig tissues. The distribution of vitamin E homologs within plasma and guinea pig tissues was determined using a high-performance liquid chromatography (HPLC) system. Lipid hydroperoxides in lipid emulsions were determined using a commercial kit (Cayman Chemical Company, Ann Arbor, MI), and malondialdehyde tissue levels were determined using an HPLC system. The lipid emulsions contained variable amounts of tocopherols, which were significantly different between emulsions. Tocotrienols were present at very low concentrations (≤0.3%). We found no correlation between the amount of vitamin E present in the lipid emulsions and lipid peroxidation. Hydroperoxides were the lowest with an olive oil-based emulsion and highest with a fish oil emulsion. The predominant vitamin E homolog in guinea pig tissues was α-tocopherol. No tissues had detectable levels of tocotrienols. Vitamin E levels (primarily α-tocopherol and γ-tocopherol) were highly variable among organ tissues. Plasma levels were a poor reflection of most tissue levels. Vitamin E levels within different lipid emulsions and plasma/tissues are highly variable, and no one tissue or plasma sample serves as a good proxy for levels in other tissues. All study emulsions were well tolerated and did not significantly increase systemic lipid peroxidation. © 2014 American Society for Parenteral and Enteral Nutrition.

Effect of acrylic acid on the properties of polyvinylpyrrolidone ...

African Journals Online (AJOL)

Hydrogels based on polyvinylpyrrolidone (PVP) networks grafted with acrylic acid (AAc) was prepared by using γ-rays from a Co-60 source at room temperature. The parameters like effect of radiation dose and concentration of AAc were studied. The properties such as gel content, swelling behavior and thermal stability ...

Synthesis and characterization of thermal energy storage microencapsulated n-dodecanol with acrylic polymer shell

International Nuclear Information System (INIS)

Ma, Yanjie; Zong, Jiwen; Li, Wei; Chen, Long; Tang, Xiaofen; Han, Na; Wang, Jianping; Zhang, Xingxiang

2015-01-01

Two kinds of (microencapsulated phase change materials) MicroPCMs with acrylic-based copolymer as shell and n-dodecanol as core were successfully fabricated via suspension-like polymerization and photo-induced microencapsulation, respectively. Morphology and core–shell structure were observed by (field emission scanning electron microscope) FE-SEM. Thermal properties of the microencapsulated n-dodecanol were investigated by (differential scanning calorimeter) DSC and (thermogravimetric analysis) TGA. The results indicate that the mass ratio of core to shell has great influence on the morphology, inner structure, microencapsulated efficiency and durability of the microcapsules. Besides, the effects of various solvents and UV irridiation time on the microcapsule surface were discussed as well. In the experiment carried out, metal-ion complexation was conducted by the reaction between Mn ion and carboxyl groups on copolymer shell to enhance the performance of the microcapsules with n-dodecanol encapsulated. As the results indicate, the physicochemical properties and thermal conductivity of the shell were improved after Mn ion complexation reaction. Supercooling phenomenon of n-dodecanol was depressed to some extent. In the end, the thermo-regulated fiber containing acrylic-based copolymer microcapsules was fabricated, and thermo-regulated performance test of the fiber was also conducted. - Graphical abstract: (a)∼(d) schematic diagram of microencapsulation and (e) microcapsule with core–shell structure. - Highlights: • Microencapsulated n-dodecanol with acrylic polymer shell. • Microencapsulated n-dodecanol was fabricated by photo-induced microencapsulation. • Acrylic-based copolymer microcapsules with manganese-ion complexation

Boundary lubrication of stainless steel and CoCrMo alloy based on phosphorous and boron compounds in oil-in-water emulsion

NARCIS (Netherlands)

Yan, J.; Zeng, Xiangqiong; Ren, T.; van der Heide, Emile

2014-01-01

Emulsion lubrication is widely used in metal forming operations and has potential applications in the biomedical field, yet the emulsion lubrication mechanism is not well understood. This work explores the possibilities of three different oil-in-water (O/W) emulsions containing dibutyl

(Meth)Acrylate Occupational Contact Dermatitis in Nail Salon Workers: A Case Series.

Science.gov (United States)

DeKoven, Samuel; DeKoven, Joel; Holness, D Linn

Recently, many cases of acrylate-associated allergic contact dermatitis have appeared among nail salon workers. Common acrylate-containing products in nail salons include traditional nail polish, ultraviolet-cured shellac nail polish, ultraviolet-cured gel nails, and press-on acrylic nails. Nail salon technicians seen in the occupational medicine clinic in 2015 and 2016 were identified, and their patch test results and clinical features were summarized. Patch testing was done with the Chemotechnique (Meth)Acrylate nail series, and either the North American Standard series or the North American Contact Dermatitis Group screening series. Six patients were identified, all women, ages 38 to 58. Common presentations included erythematous dermatitis of the dorsa of the hands, palms, and forearms and fissures on the fingertips. Less common sites of eruptions included the periorbital region, cheeks, posterior ears, neck, sacral area, lateral thighs, and dorsa of the feet. All patients reacted to hydroxyethyl methacrylate, and 5 patients reacted to ethyl acrylate. Each patient also reacted to (meth)acrylates that are not found on either standard series, including ethyleneglycol dimethacrylate, 2-hydroxypropyl methacrylate, and 2-hydroxyethyl acrylate. The authors report 6 cases of allergic contact dermatitis to acrylates in nail technicians seen over the past year, representing a new trend in their clinic. These cases are reflective of a growing trend of nail technicians with allergic contact dermatitis associated with occupational (meth)acrylate exposure. Efforts to improve prevention are needed.

[Contact dermatitis caused by acrylates among 8 workers in an elevator factory].

Science.gov (United States)

Pérez-Formoso, J L; de Anca-Fernández, J; Maraví-Cecilia, R; Díaz-Torres, J M

2010-05-01

Acrylates are widely used low-molecular-weight substances, initially introduced in industry in the 1930s and subsequently applied also in medicine and the home. One of their main features is the ability to undergo polymerization. The most commonly used acrylic compounds are cyanoacrylates, methacrylates, and acrylates. To confirm suspicion of occupational disease in a group of workers in an elevator factory. We studied 8 patients with dermatitis of the hands and finger pads. In their work, the patients came into contact with acrylates. Patch testing was applied with an acrylate panel (BIAL-Aristegui, Bilbao, Spain). Seven of the patients (87. 5%) had a positive result with 1% ethylene glycol dimethacrylate. Positive were also observed for 2% hydroxyethyl methacrylate (5 patients, 62. 5%), 1% triethylene glycol dimethacrylate (4 patients, 50%), 10% ethyl methacrylate monomer (3 patients, 37. 5%), 10% methyl methacrylate monomer (2 patients, 25%), 1% ethyl acrylate (1 patient, 12. 5%), and 0. 1% acrylic acid (1 patient, 12. 5%). We highlight the strong sensitizing capacity of acrylates and the importance of taking all necessary preventive measures in industries where these substances are used. Such measures should include avoidance of contact with the product in cases where sensitization has been confirmed.