Recent compatibilization strategies in poly(lactic acid)-based blends have been reviewed in this paper.

Poly(lactic acid) (PLA) is regarded as one of the most promising biobased and biodegradable polymers due its various advantages including high mechanical strength, easy processability, high melting temperature, renewability, biodegradability, and biocompatibility. However, the inherent brittleness significantly restricts its wide application. Therefore, toughening PLA has attracted more and more attention and various materials have been used to blend with PLA for toughening. Considering the fact that the use of petroleum-based species to toughen PLA would partially sacrifice the sustainability, various renewable polymers have recently been employed to toughen PLA. A series of important achievements have been obtained but not reviewed. This article aims to review progress in toughening PLA with renewable polymers. The toughening theories and compatibilization strategies are also briefly introduced.

Poly(butylene adipate-co-terephthalate) (PBAT) and poly(lactic acid) (PLA) are well-known biodegadable polyesters due to their outstanding performance. The biodegradation behavior of PLA/PBAT blends in freshwater with sediment is investigated in this study by analyzing the appearance, chemical structure and aggregation structure of their degraded residues via SEM, TG, DSC, gel permeation chromatography (GPC) and XPS. The effect of aggregation structure, hydrophilia and biodegradation mechanisms of PBAT and PLA on the biodegradability of PLA/PBAT blends is illuminated in this work. After biodegradation, the butylene terephthalate unit in the molecular structure of the components and the molecular weight of PLA/PBAT blends decreased, while the content of C-O bond in the composites increased, indicating that the samples indeed degraded. After 24 months of degradation, the increase in the relative peak area proportion of C-O to C=O in PLA/PBAT-25, PLA/PBAT-50 and PLA/PBAT-75 was 62%, 46% and 68%, respectively. The biodegradation rates of PBAT and PLA in the PLA/PBAT blend were lower than those for the respective single polymers.