Effects of dynamic vulcanization on the properties of thermoplastic tapioca starch / high density polyethylene / natural rubber

Abstract

Effects of dynamic vulcanization on the morphology and tensile properties of high density polyethylene/natural rubber/thermoplastic tapioca starch (HDPE/NR/TPS) blends were investigated. The ratio between HDPE/NR was fixed at 70/30 and used as the matrix system. TPS loadings for unvulcanized and vulcanized systems were varied from 0% to 30wt%. Morphology and tensile properties of HDPE/NR blends were evaluated as a function of TPS loadings. The tensile strength, Young’s modulus and elongation at break were found to decrease with TPS content. However an improvement in the tensile properties for vulcanized blends was observed. The degree of TPS adhesion and dispersion in HDPE/NR blends were determined by scanning electron microscope (SEM). SEM showed the vulcanized blends have better dispersion with smaller TPS particle size and it also embedded on HDPE/NR matrix.