Terpolymerization of Glycolide, Cyclohexene Oxide and CO2 for Crystalline Poly(carbonate-esters)

Abstract Polyglycolide (PGA) is a crystalline polyester with notable mechanical properties, biodegradability, and biocompatibility. Incorporating PGA into amorphous epoxide/CO2 copolymers presents a promising strategy for obtaining biodegradable crystalline plastics. In this work, a zinc–cobalt(III) double metal cyanide complex [Zn–Co(III) DMCC] was firstly employed to catalyze the one-pot terpolymerization of glycolide (GA), CO2, and cyclohexene oxide (CHO), affording a terpolymer with a catalytic efficiency of 1.54 kg terpolymer/g catalyst and a molecular weight (Mn) of up to 59.3 kDa. The influence of the [CHO]/[GA] feed ratios on the terpolymer composition was elucidated. Specifically, at [CHO]/[GA] ratios of 99/1 and 97/3, the resulting products exhibited glass transition temperatures (Tg) of 99.1 and 104 °C, respectively. While at [CHO]/[GA] ratios ranging from 93/7 to 50/50, melting temperatures (Tms) of 211.6–219.3 °C were detected for the terpolymers, indicating the formation of crystalline poly(carbonate-esters). The results offer a practical pathway towards high-performance modification of epoxide/CO2 copolymers.