Mechanisms of Reinforcement of Elastomers by Polymeric Fillers

Publisher Website
Google Scholar
Abstract
Two systems have recently been studied involving elastomeric networks reinforced by finely-divided glassy polymeric fillers. One of these was prepared by blending latices of polystyrene, or other glassy polymers, with SBR, and vulcanizing the resulting elastomer. It was found that the tensile strength of the SBR increased with higher filler content, lower particle size and increase in rigidity of the filler, and was virtually unaffected by filler-elastomer bonds. The other system studied consisted of the "thermoplastic elas tomers" prepared from styrene-diene-styrene triblock polymers. Here the polystyrene forms small "domains" (∼200A) which act both as network junctions and reinforcing filler. These glassy par ticles yield at high stresses, thus relieving high stress concentra tions and resulting in high tensile strength but large inelastic de formations.