Plasticize Me Sweetly: Sugar-Based Plasticizers for Poly(lactic acid)

Carbohydrates are among the most abundant biopolymers in the world and offer a promising source for the synthesis of value-added chemicals. Galactaric acid is an attractive biobased building block that has not yet been fully exploited. Currently, regulatory, sustainability, safety-by-design, and performance requirements for polymer additives are becoming increasingly strict. As a result, innovation in this field must be accelerated to develop new materials with enhanced properties. With this objective, new sugar-based plasticizers based on galactaric acid have been synthesized. Poly(lactic acid) (PLA) was selected as a brittle, biobased polymer, to evaluate the ability of these additives to improve its mechanical properties. The best additive led to an increase of the elongation at break up to 260% when compared to the starting PLA. Experimental results have been supported by computational studies and show how small modifications in the molecular structure can influence both the synthesis and the performance of these additives.