The effect of citric acid on the mechanical properties of thermoplastic tapioca starch/high density polyethylene/natural rubber blends

摘要

Effects of citric acid on the mechanical properties of thermoplastic tapioca starch/high density polyethylene/natural rubber (HDPE/NR/TPS) blends were investigated. The ratio between HDPE/NR was fixed at 70/30 and used as a matrix system. TPS loadings with and without modification with citric acid (CA) were varied from 0% to 30wt%. Mechanical and physical properties of blends were evaluated as a function of TPS loadings modified with and without CA. The tensile strength, Young's modulus and elongation at break were found to decrease with increasing TPS content. However an improvement in the tensile strength for TPS modified with CA at 5%, 10% and 20% TPS loadings was observed. The degree of TPS adhesion and dispersion in HDPE/NR blends were determined by scanning electron microscope (SEM).