This review describes recent strategies for synthesizing polymers that are mostly or fully biobased and exhibit a high glass transition temperature.

Itaconic acid, a naturally occurring compound mass-produced via fermentation of glucose, was reacted with ethanolamine or ethylene diamine to afford hydroxy-acid or diacid monomers containing the 2-pyrrolidone lactam. Homopolymerization or copolymerization with diols, respectively, yielded polylactam esters with higher glass transition temperatures and faster hydrolytic degradation compared to the commercial polyester polylactic acid (PLA).

Concurrent ring-opening polymerization/polycondensation of lactones and bioaromatic hydroxy-acids yields random copolymers with improved and controlled thermal properties.