Poly(tetramethyl glycolide) from Renewable Carbon, a Racemization-Free and Controlled Depolymerizable Polyester

Racemization-free and depolymerization-controllable poly(tetramethyl glycolide) (PTMG) was synthesized from renewable resources: D/L-lactic acids and pyruvic acid. PTMG overcomes the undesirable properties of poly(lactic acid) such as low heat-resistance and racemization causing the decrease in crystallinity. PTMG was shown to have a higher melting point than 200 °C and to be a superior recyclable material capable of being depolymerized controllably into cyclic dimer tetramethyl glycolide (TMG) or methacrylic acid (MA) by using specific catalysts. PTMG can be reversibly synthesized from the depolymerized TMG. Moreover, biomass-based poly(methyl methacrylate) (PMMA) was prepared from the recovered MA.