Full Text Available The aim of the research was to study the influence of utilization of sulphur and reclaim rubber on the characteristics of ebonite rubber, and also to determine the optimum utilization of reclaim rubber and sulphur which yield good physical properties. Ebonite rubber was made by special natural rubber of RSS I (Ribbed Smoke Sheet I mixed with reclaimed rubber at ratio 80/20, 70/30 and 60/40 part hundred rubber/part hundred rubber (phr/phr and utilization of sulphur 30, 40, and 50 phr and also additives respectively. Mixing was done by using open mill, and vulcanization was conducted at early temperature 1200C for 2 hours, and it was continued by post curing at temperature 1500C for 2 hours. The physical properties such as tensile strength, elongation at break, D shore hardness, and izod impact of ebonite rubber vulcanized were determined. The result indicated that characteristics of ebonite rubber was significantly influenced by the amount of added sulphur and 40 phr reclaim rubber or at ratio of RSS I to reclaim rubber 60 to 40 phr/phr. However, the physical properties of ebonite rubber was able to meet the standard quality of group 2 regarding to Classification Hard Rubber issued by ASTM D 2135
Full Text Available Tujuan penelitian ini adalah menyelidiki pengaruh variasi sulfur 25 dan 30 phr (per hundred rubber komposit berpenguat serat kenaf dan peningkatan kekuatan tarik, bermatrix hard natural rubber (Ebonite. Bahan utama penelitian adalah compount natural rubber/ebonite, serta kenaf acak. Komposit dibuat dengan metode cetak tekan panas (Hot Press Mold. Komposit tersusun terdiri dari serat kenaf dengan ebonite. Fraksi berat serat kenaf 8%. Spesimen dan prosedur pengujian tarik mengacu pada standar ASTM D 638-02. Hasil penelitian ini menunjukkan pengaruh variasi sulfur 25 dan 30 phr terhadap kekuatan tarik pada komposit berpenguat serat kenaf meningkat. Kekuatan tarik komposit berpenguat serat kenaf sebesar 12 dan 29 Mpa. Kekuatan tarik memiliki harga yang paling optimum pada komposit berpenguat serat kenaf dengan variasi sulfur 30 phr.
Babaeva, N. A.; Vas'kovskiĭ, Yu M.; Rovinskiĭ, R. E.; Ryabinkina, V. A.
Measurements were made of components of the energy balance in the interaction of pulsed CO2 laser radiation with Dural, glass, quartz, ebonite, and Plexiglas in air at atmospheric pressure. At laser energy densities between 1 and 20 J/cm2 and in the spectral range 0.2-7 μm, the re-emission of radiation by the laser plasma was found to be less than 1 %. At energy densities exceeding 10 J/cm2, up to 90% of the laser energy failed to reach the irradiated surface.