Synthesis of Levulinic Acid-Based Block Copolyesters with Tunable Degradation

Fully biobased block copolyesters were synthesized from glycerol, 1,3-propanediol, levulinic acid, and malonic acid via melt polycondensation. These copolyesters are designed for potential biomedical applications, such as stents, where controlled degradation and optimized material performance are essential. The influence of monomer molar ratios on the thermal and mechanical properties of the copolyesters was studied to understand the structure–property relationships. To further enhance material properties, itaconic acid, a renewable biomonomer with a reactive double bond, was incorporated for cross-linking with dicumyl peroxide. The addition of malonic acid significantly influenced the glass transition temperature (Tg), thermal stability, and degradation behavior of the copolyesters. Thermogravimetric analysis (TGA) revealed thermal degradation temperatures (T5% and Tmax) exceeding 233 and 353 °C, respectively. The in vitro degradation of the copolyesters could be precisely tuned by adjusting the monomer composition, providing the potential for customizable biomedical devices that degrade in a controlled manner over time.