Effects of silica content on the formation and morphology of ENR/PVC/Silica composites beads

The effects of silica content in preparing silica-filled epoxidized natural rubber/polyvinyl chloride (ENR/PVC) beads were investigated. ENR/PVC matrix blend used was of composition 60% (ENR50) and 40% (PVC) by weight. The matrix blend was then dissolved in tetrahydrofuran (THF) by sol-gel technique prior to addition of silica fume as filler at varying amounts up to 25 wt% of the matrix mass. The composites beads were formed via phase inversion method by dropping the polymeric solution into a non-solvent. The size and shape were improved by adding in an increased amount of silica. Morphological studies showed distinct features of beads’ surface in terms of homogeneity of silica particle distribution and presence of agglomerations and voids within the ENR/PVC matrix. Formation of silica network was apparent on the bead at 25 wt% silica content. The bead formation was found to be significantly affected by the silica loading in the ENR/PVC solution.