在异辛酸亚锡催化下,ε-己内酯与官能团化ε-己内酯单体6-(乙酸苄基酯基)-ε-己内酯(BCL)开环共聚合成含有侧乙酸苄基酯基的ε-己内酯/6-(乙酸苄基酯基)-ε-己内酯共聚物(PCL-co-PBCL).然后通过钯/碳催化加氢脱除PCL-co-PBCL的苄基保护基,得到含侧乙羧基官能团的ε-己内酯/6-乙酸基-ε-己内酯共聚物(PCL-co-PCCL).研究了两种聚合物的力学性能、表面亲水性及其在37℃温度下在不同pH值的缓冲溶液中的降解行为.实验结果表明:侧基官能团,尤其是侧乙羧基官能团的引入可明显改善聚己内酯的亲水性和降解性,且降解速度可通过控制聚合物中官能团的含量来进行调节.
Poly(e-caprolactone) functionalized with pendant benzyloxycarbonylmethyl group (PCL-co- PBCL) was synthesized by the ring-opening polymerization of ε-caprolactone and ε-(benzyloxycarbonylmethyl)-ε-caprolactone (BCL) with Sn(Oct)2 as catalyst. Its benzyl protecting groups were effectively removed by H2 using Pd/C as catalyst to obtain poly(ε-caprolactone) bearing pendant carboxyl groups (PCL-co-PCCL). We studied the mechanical properties and surface hydrophilicity of PCL-co-PBCL and PCL-co-PCCL, and the degradation behavior in vitro of them was also evaluated in different pH value phosphate buffer solutions. The results showed that the degradability of functionalized PCL was greatly im- proved by the pendant functional groups and the degradation rates could be controlled by adjusting the content of the functional groups.