Influence of oxidized starch on the properties of thermoplastic starch

Thermoplastic starch was prepared by adding oxidized starches and glycerol together into starch. The addition of oxidized starch improved the rheological properties and also increased the toughness of thermoplastic starch. Compared with TPS30, the elongation at break increased from 126.8% to 152.5% when 5 wt% OS 117% was added. Good compatibility of thermoplastic starch between the matrix and oxidized starch was confirmed by SEM. The addition of oxidized starch lowered the storage modulus and glass transition temperature (Tg) of thermoplastic starch, decreasing Tg from 34.1 to 30 °C when 10 wt% OS117% was added. The thermal stability of blending was improved by adding oxidized starches, i.e. when 5 wt% OS70% was added, T5% increased from 134 to 156 °C.