Development of Biodegradable and Biobased Poly(glycerol levulinate-<i>co</i>-glycerol malonate) Copolyesters with Controlled Degradation

Fully biobased oligomers were synthesized from glycerol, levulinic acid, and malonic acid via melt polycondensation. Itaconic acid with a carbon-carbon double bond was incorporated to enable cross-linking using dicumyl peroxide. The effect of the monomer molar ratio on material properties was investigated to understand the structure-property relationships. The addition of malonic acid, acting as both a monomer and a secondary cross-linker, was found to tune the glass-transition temperature, thermal stability, and degradation behavior of the cross-linked random copolyesters. Thermogravimetric analysis (TGA) revealed that malonic acid significantly improved the thermal stability, increasing it by up to 7.6% compared to the neat polymer. The cross-linked copolyesters exhibited excellent degradation profiles, making them suitable for biomedical applications where controlled degradation is essential. Additionally, they demonstrated outstanding shape memory properties, with a nearly 100% shape recovery, offering further potential for biomedical device fabrication.