• polyesters;
  • ring-opening polymerization;
  • serine;
  • N-trityl-L-serine-β-lactone


Novel polyesters, poly[(ε-caprolactone)-co-(N-trityl-L-serine-β-lactone)]s, were prepared by copolymerizing ε-caprolactone (CL) with N-trityl-L-serine-β-lactone (TSL) using ZnEt2 as the catalyst. The number-average molecular weights were determined which ranged from 2.7 × 104 to 4.9 × 104 Da with dispersity values ranging from 1.6 to 1.8. The structures of the copolymers were investigated by means of 1H NMR, 13C NMR and infrared spectroscopies, thermogravimetric analysis and differential scanning calorimetry. The results indicated that CL and TSL monomer units were randomly distributed within the copolymer backbone structures and the ratios of TSL to CL in the copolymers were close to those in the feeds. After removal of the trityl group under mild condition, a new polyester with side amino groups provided by serine units was obtained. L929 cell culturing test indicated good biocompatibility of the polyester with or without protective groups. © 2012 Society of Chemical Industry