Modification of Thermoplastic Starch to Achieve a Broad Range of Properties in Mixture With Biodegradable Polymers

Thermoplastic starch (TPS) is often a component of the mixtures with biodegradable plastics (BDP) aimed to a decrease of the price of biodegradable material. The acceptable ultimate properties are achieved only by the addition of a compatibilizer able to make the mixture of usually hydrophobic apolar BDP with highly polar TPS compatible enough. Other physical properties are crucial, especially moisture uptake due to the effect on mechanical properties, as well as barrier properties important due to the application of BDP as foils for food packaging. In both cases, the presence of TPS is the main reason considering the acceptable performance of the final mixture with BDP, therefore, the relevant properties of TPS may substantially affect the ultimate properties of the BDP/TPS mixtures. In the lecture, the key physical data on TPS are presented, especially the moisture uptake during storing as well as the permeation coefficients of gases. Finally, a new effective compatibilizers is shown and its effect on mechanical properties of PBAT/ TPS mixtures are presented.