Synthesis and in vitro degradation properties of poly[(tetramethylene carbonate)‐co‐(sebacic anhydride)]

A novel poly[(tetramethylene carbonate)‐co‐(sebacic anhydride)] (PTCSA) was synthesized by the melt polycondensation reaction of sebacic acid (SA) and the dicarboxylic acid which derived from oligo(tetramethylene carbonate) diol via the corresponding mixed anhydrides. The copolymer structure was confirmed by means of FTIR and [¹H] NMR spectra. DSC analysis showed PTCSA was semicrystalline polymer which had low T_g (In vitro degradation of PTCSA was performed in lipase‐free and lipase‐containing phosphate‐buffer saline (0.1 M, pH 7.4) at 37 °C. It was found that the degradation rate of PTCSA increased with the amount of SA. After 7 days of degradation in lipase‐free phosphate‐buffer saline, the weight loss of PTCSA was 74, 49 and 22% for 80, 58 and 32 mol% SA contained samples, respectively. The weight loss of PTCSA increased rapidly in the first week, then slowed down but could be greatly enhanced by lipase. After 3 weeks of degradation with or without lipase, the weight loss of PTCSA was 66 and 52% for 58 mol% SA‐containing samples, respectively. The size of the samples was gradually reduced and the surface became coarse. It was also found that the molecular weights of the outer layer were lower than those of the inner layer of the samples after degradation. The results suggested that PTCSA was some kind of biodegradation and surface‐erosion material. © 2001 Society of Chemical Industry