Poly-lactic acid self-reinforcing composites with improved toughness utilising solid-state drawn oriented tape

Abstract

With the increasing white pollution problem and the enhancement of people’s awareness of environmental protection, the bio-based and biodegradable polymers have received unprecedented attention. Poly-lactic acid (PLA) is considered as one of the most potential alternatives to petroleum-based polymer materials. However, Due to its inherent brittleness and the difficulties of post-disposal and recycling caused by traditional processing methods, PLA has not been fully accepted by the market. To overcome the issues, self-reinforcing PLA composites (SRPLA) were prepared with different PLA grades as the matrix and the reinforcement respectively. High toughness SRPLA were prepared by hot pressing using PLA3052 casting films as the matrix and PLA6202 oriented tapes fabricated by solid state drawing as the reinforcement. In addition, the toughening mechanism was analyzed. Mechanical tests showed that the strength, modulus and elongation at break were increased by 124.3%, 114% and 145.2% respectively compared with pure PLA hot pressed film. Particularly, the tensile toughness of SRPLA is more than 200% that of pure PLA. The interface debonding and tape pullout were the main toughening mechanisms.