Fully biodegradable Poly(lactic acid)/Starch blends: A review of toughening strategies

Polylactic acid (PLA) and Starch are both bio-based biodegradable polymers that have properties that are complementary to each other. PLA/starch blend exploits the good mechanical property of PLA and the low cost of Starch. However, PLA/Starch blend is intrinsically brittle. This paper reviews the current state of arts in toughening of PLA/Starch blend, which are categorized as: Additive Plasticization, Mixture Softening, Elastomer Toughening and Interphase Compatibilization. These strategies are not mutually exclusive and can be applied jointly in a single blend, opening up a wide range of toughening techniques that can be employed in PLA/Starch blend. Even though significant progress has been made in this area, there is still much room for research, in order to achieve easy to process, fully bio-based and completely biodegradable PLA/Starch blends that have mechanical properties suitable for a wide range of applications.