Natural Rubber Composites (natural + rubber_composite)

Distribution by Scientific Domains

Selected Abstracts

Lead,Natural rubber composites as gamma radiation shields.

II: High concentration
Natural rubber composites were prepared by the incorporation of different lead concentration, namely: 100, 300, 500, 1000, 1500 and 2000 phr to be used as gamma radiation shields. A non-linear dependence of the attenuation coefficient upon the lead concentration was observed for both 60Co and 137Cs as gamma radiation sources. Sample containing the ultimate lead concentration (2000 phr) and thickness 1 mm was found to have 0.336 mm and 0.383 mm lead equivalent for 60Co and 137Cs respectively. Electrical and mechanical properties of the investigated composites were also measured. [source]

The Effect of Silane Coupling Agents on the Viscoelastic Properties of Rubber Biocomposites

Maya Jacob
Abstract Summary: This paper deals with the dynamic mechanical study of sisal/oil palm hybrid fiber reinforced natural rubber composites (at frequency 1 Hz) with reference to the role of silane coupling agents. Composites were prepared using sisal and oil palm fibers subjected to chemical modifications with different types of silane coupling agents. The silanes used were Silane F8261 [1,1,2,2-perfluorooctyl triethoxy silane], Silane A1100 [, -aminopropyltriethoxy silane] and Silane A151 [vinyl triethoxy silane]. It was observed that for treated composites, storage modulus and loss modulus increased while the damping property was found to decrease. Maximum E' was exhibited by the composite prepared from fibers treated with silane F8261 and minimum by composites containing fibers treated with silane A151. This was attributed to the reduced moisture absorbing capacity of chemically modified fibers leading to improved wetting. This in turn produced a strong interfacial interface giving rise to a much stiffer composite with higher modulus. Surface characterization of treated and untreated sisal fibers by XPS showed the presence of numerous elements on the surface of the fiber. Scanning electron micrographs of tensile fracture surfaces of treated and untreated composites demonstrated better fiber,matrix bonding for the treated composites. Scheme of interaction of silanes with cellulosic fibers. [source]

Molecular transport of aromatic hydrocarbons through lignin-filled natural rubber composites

Thomas V. Mathew
The diffusion and transport of organic solvents through lignin-filled natural rubber composites have been studied in the temperature range 25,45C. The diffusion of aromatic solvents through these samples were studied with special reference to the effect of filler concentration, penetrant size, and temperature. Transport coefficients such as diffusion, permeation, and sorption coefficients were estimated. The van't Hoff relationship was used to determine the thermodynamic parameters. The first order kinetic rate constant has been evaluated. A correlation between theoretical and experimental sorption results was evaluated. POLYM. COMPOS., 28:15,22, 2007. 2007 Society of Plastics Engineers [source]