Natural rubber (NR), regarded as nature's most versatile raw material is obtained from the latex of Hevea brasiliensis, a tree, native to the tropical rain forests of Amazon and introduced on a commercial scale to the Far East during the last century. In India, organised cultivation of rubber started in 1902 on an estate scale by European planters. This crop however came out of the bounds of th...

The rubber-producing tree, Ficus elastica (the Indian rubber tree), requires the same substrates for rubber production as other rubber-producing plants, such as Hevea brasiliensis (the Brazilian or Para rubber tree), the major source of commercial natural rubber in the world, and Parthenium argentatum (guayule), a widely studied alternative for natural rubber production currently under commerci...

Effect of different fillers on natural rubber compounds was investigated through curing, mechanical properties and morphology studies for improving mechanical performance of rubber articles. In this work, natural rubber blends with Silica as Single-filler compounds, and blends with Silica and Carbon black as Bi-filler compounds were considered. Then, natural rubber blends with Silica, Carbon bl...

in some special cases, rubber compounds with high amounts of unsaturated elastomer are recommended with organic sulfur donors instead of mineral sulfurs. in this condition, activated sulfur is produced in situ and curingprocess is facilitated without accelerators. organic sulfur donor compounds have low thermal stability and in the vulcanization temperature produce free and activated sulfurs. t...

Abstract: Rubber tree (Hevea brasiliensis) plantation is a major land use practiced in Xishuangbanna of south-western China. Effects of rubber plantation (RP) and tea-rubber intercropping (TRI) systems on soil organic carbon pools were evaluated by recording changes in soil organic carbon in an age sequence of 12-, 20-, 26-, and 40-year old plantations. Labile organic carbon (LOC) increased in ...

Objective: Peripheral Arterial Disease (PAD) is a state characterized by atherosclerotic occlusive disease of lower extremities. Diabetes is the main risk factor for PAD. Material and Methods: To assess the prevalence of PAD, a cross sectional study was performed on 352 diabetic patients who referred to Yazd diabetes research center from 2007 to 2010. Vascular assessment was done by measuring ...

About 22,000 1-methyl-3-nitro-1-nitrosoguanidine- and UV-induced mutants of the rubber-degrading bacterium Streptomyces sp. strain K30 were characterized for the ability to produce clear zones on natural rubber latex overlay agar plates. Thirty-five mutants were defective solely in cleavage of rubber and were phenotypically complemented with the wild-type lcp (latex clearing protein) gene. Sixt...

Abstract Process-induced residual stresses significantly influence the mechanical properties of a formed component. A polymer pad is used as flexible die in two-point incremental forming to induce compressive component during process. Experimental and numerical results illustrate stress superposition on properties. It shown that active support, using geometry-independent polyurethane die, cause...

Natural rubber is produced by a rubber transferase (a cis-prenyltransferase). Rubber transferase uses allylic pyrophosphate to initiate the rubber molecule and isopentenyl pyrophosphate (IPP) to form the polymer. Rubber biosynthesis also requires a divalent metal cation. Understanding how molecular weight is regulated is important because high molecular weight is required for high quality rubbe...