Rheological behavior of blends of natural rubber and styrene–butadiene rubber latices

Abstract

SYNOPSISThe rheological behavior of blends of natural rubber (NR) and styrene-butadiene rubber (SBR) latices has been studied with reference to the effects of blend ratio, shear rate, surface-active agents (casein and sodium carboxymethyl cellulose), and temperature. When the SBR content was less than 50%, the viscosities of the blends appeared to be a nonadditive function of the viscosities of the constituent homopolymers; i.e., a positive deviation was observed. This was due to the structural buildup of the SBR domains. The SBR domains underwent agglomeration and consequently so-called microflocculation took place. The viscosities of all the blends were found to decrease with increase of temperature and shear rate. The increase in temperature and shear rate marginally weakened the structural buildup as evidenced by the lowering of viscosity. As the SBR content in the system increased, the pseudoplasticity of the blend increased. Even in the presence of surface-active agents the blends showed composition-dependent positive deviation. However, surface-active agents marginally reduced the extent of structural buildup by reducing the microflocculation behavior of SBR domains. 0 1995 John Wiley

Morphology and mechanical and viscoelastic properties of natural rubber and styrene butadiene rubber latex blends

“…Equation 19 is the same as the parallel model equation. Another important model for perfect adhesion is the Kerner equation.…”

Effective thermal conductivity of three-phase styrene butadiene composites

“…6,7 The reuse of waste rubber is important not only from the point of view of economy but ecology also, because natural rubber takes decades to decompose. Various types of studies on morphology, mechanical propreties, 8,9 and rheological behavior of the NR latex waste-filled SBR compounds have already been made. However, no serious effort has been made so far to study the thermal properties such as thermal conductivity and thermal diffusivity of these composites.…”

Effects of Nanosized Polystyrene and Polystyrene-Encapsulated Nanosilica on Physical Properties of Natural Rubber/Styrene Butadiene Rubber Nanocomposites

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