Effect of nano-alumina concentration on the properties of poly(vinyl chloride)/thermoplastic polyester elastomer blend system

Abstract

Poly(vinyl chloride) (PVC)/thermoplastic polyester elastomer (Hytrel) blend system prepared in 50/50 composition was found to have the highest possible percentage elongation-at-break. This is due to better molecular compatibility between the two; however, they had lower strength and modulus values. In order to improve the strength and modulus property, alumina nano-particles were added as a reinforcing agent in concentrations as 1, 3, 5, and 7 phr in the blend system. The prepared nanocomposites were characterized for mechanical, thermal, rheological, morphological, and electrical properties. The 5-phr nano-alumina loaded PVC/Hytrel blend had optimal improvement in its strength values, but above that concentration nano-alumina started forming aggregates as was apparent from scanning electron microscopy (SEM) analysis. SEM images showed uniform distribution of nano-alumina in both PVC and Hytrel phases of the blend. Tensile strength and modulus were found to have increased by about 20 and 97 %, respectively, whereas elongation at maximum load decreased by 50 %, indicating the effect of nano-alumina as a reinforcing agent in the PVC/Hytrel system. The glass transition temperature, onset degradation temperature, viscosity, surface resistivity and volume resistivity increased, whereas degradation weight loss (%) decreased with increase in nano-alumina concentration in PVC/Hytrel blend system. No chemical interaction happened between PVC, Hytrel or alumina nano-particles, as proved by FTIR analysis.