Synthesis, characterization and in vitro degradation of a novel degradable poly((1,2-propanediol-sebacate)-citrate) bioelastomer

Degradable bioelastomers represent a useful class of biomaterials. In this paper, a novel biodegradable network of elastomeric polyesters, poly((1,2-propanediol-sebacate)-citrate) (PPSC), was synthesized by condensation of 1,2-propanediol, sebacic acid and citric acid without any catalyst. An oligomeric diol of 1,2-propanediol-sebacate was first synthesized by carrying out a controlled condensation reaction between 1,2-propanediol and sebacic acid, and then a pre-polymer was synthesized by condensation of the diol and citric acid, whereat the pre-polymer was post-polymerized and simultaneously crosslinked in mold at 120 °C. A series of PPSC polymers were prepared at different post-polymerization times and different monomers' ratio. T_g confirms that PPSC is totally amorphous at 37 °C. The mechanical properties of PPSC testified that the new polymers are typical elastomers with low hardness and large elongation. The different post-polymerization times and monomers' ratio had strong influence on the degradation rates and mechanical performances. The material was expected to be useful for drug controlled delivery, tissue engineering scaffold and other biomedical applications.