Reinforcement of Polylactic Acid / Poly Butylene Adipate-co-Terephthalate blends by starch addition: a coupled computational and experimental study

Abstract

Poly Lactic Acid / Poly Butylene Adipate-co-Terephthalate blends are used as packaging green materials since they constitute hydrophilic and biodegradable plastic. With the aim of improving the mechanical characteristics of such blends as biodegradable packaging materials for food products the addition of starch has been considered. In silico test performed by classical molecular dynamics highlighted that the addition of starch can reinforce the polymeric structure via starch-polymer interactions, suggesting that starch can be a suitable material to be added to the Poly Lactic Acid / Poly Butylene Adipate-co-Terephthalate blend to obtain more resistant packaging materials. Experimental analysis of the mechanical properties of the polymeric blend containing different amounts of starch confirmed what foreseen by MD, highlighting an increase of Young modulus and glass transition as a function of added starch. The coupled theoretical/experimental approach constitutes added value of the present work, furnishing important data on the reinforcement of the packaging material performances and a molecule-based interpretation and comprehension of the observed phenomenon.