Synthesis of bio-based poly(butylene carbonate-co-glycolic acid) with tunable degradation rate and mechanical properties

Bio-based copolymers with excellent mechanical properties and biodegradability are highly desired for packaging and agricultural applications. In this work, a series of high molecular weight bio-based poly(ester-carbonate)s are synthesized using glycolic acid (GA), dimethyl carbonate (DMC), and 1,4-butanediol (BDO). The intrinsic viscosity ([eta]) of these copolymers ranges from 0.70 to 1.11 dL/g. The tensile strength, elastic modulus, and elongation at break of PBCGA10 are 19.69 +/- 2.40 MPa, 151.20 +/- 37.17 MPa, and 1173 +/- 142%, respectively, which are superior to the mechanical properties of PBAT. The degradation weight loss of PBCGA10 and PBCGA20 after 30 days can reach 8% and 40%, respectively, indicating excellent degradation performance of the copolymers. Moreover, copolymers undergo degradation through a surface degradation mechanism. The main products of copolymer degradation are BDO, CO2, and H2O, which do not cause harm to organisms and the environment.