Particle morphology of epoxidised natural rubber latex prevulcanized by peroxide system

Abstract

Epoxidised natural rubber (ENR) latex could be prevulcanized by employing tert-butyl hydroperoxide/fructose system. By applying the phase transfer/bulk polymerization/ transmission electron microscopy (TEM) technique, the uniform crosslink distribution in peroxide-prevulcanized (PP) ENR particle was observed. However, the membrane layer of protein-lipid complex, originally existing at rubber particle surface, could not be detected. Results implied that the alkoxy radicals penetrated throughout the rubber phase. The diffusion rate of radicals should be equal to that of vulcanization. Under TEM, the uniform mesh-like particle and cluster of the rubber chains were observed in PP(NR/ENR) while micrographs of PP-NR/PP-ENR blends showed only the crosslinked particles whose structure correlated well with that of PP-NR.