Effects of Starch Content and Compatibilizer on the Mechanical, Water Absorption and Biodegradable Properties of Potato Starch filled Polypropylene Blends

Abstract

Tensile, water absorption and biodegradable properties of potato starch filled polypropylene blends have been investigated. Polypropylene grafted maleic anhydride (PP-g-MA) was used as compatibilizer. It was observed that the tensile strength and elongation at break are inversely related to the starch content but Young’s modulus followed a direct relationship with the starch content. However, the addition of PP-g-MA to the blends improved the tensile strength and elongation at break even though they were still lower than the neat polymer but the Young’s modulus increased progressively. This is as a result of the enhanced interfacial bonding between the starch and matrix which can be proved by the SEM images. The tensile strength and elongation at break of the compatibilized blends increased by 30.59%; 42.62% and 23.36%; 24.62% in comparison with the uncompatibilized blends at 10 wt.% and 50 wt.% respectively. The percent water absorbed and weight loss of the PS/PP were higher than the CPS/PP blends due to poor interfacial bonding. Biodegradation products of the blends showed no deleterious effects on the growth of plants.