Copolymers of itaconic anhydride and methacrylate-terminated poly(lactic acid) macromonomers

In an effort to design cyclic anhydride copolymers that have biodegradable characteristics and are derived from renewable resources, the copolymerization of itaconic anhydride and methacrylate-terminated poly-(L-lactic acid) (PLLA) was studied. Polymers with anhydride concentrations from 85 to 15 mol% have been synthesized successfully with retention of the cyclic anhydride. Molecular weights range from 9000 to 70,000 with higher molecular weights for higher concentrations of PLLA macromonomer. High conversions are observed for samples containing 50% and less itaconic anhydride with a slight tendency for the polymer to be enriched in the monomer in smaller concentration. These copolymers show glass transition temperatures between 31 and 73 degrees C, increasing with increased itaconic anhydride content. No evidence of crystallinity from the PLLA is observed for these copolymers.