β-环糊精/聚(DL-丙交酯)接枝共聚物的合成与表征

以β-环糊精(β-CD)为接枝骨架、DL-丙交酯(DLLA)为接枝单体,三乙胺为催化剂,合成了β-环糊精/聚(DL-丙交酯)接枝共聚物(PCDLA).利用IR、1H-NMR、DSC、WXRD和GPC等方法对接枝共聚物的结构进行了表征,测定了共聚物的分子量,并研究了反应投料比对单体转化率(C%)、接枝率(G%)和接枝效率(GE%)的影响.结果表明,在三乙胺催化下,DL-丙交酯与β-环糊精能够发生聚合反应得到接枝共聚物,当DL-丙交酯与β-环糊精结构单元的摩尔比为30∶1,反应时间为10h时,接枝反应的接枝率(G%)和接枝效率(GE%)可分别达到182·9%和21·4%.随着接枝共聚物中β-环糊精含量的增加,共聚物的亲水性得到了改善.

SYNTHESIS AND CHARACTERIZATION OF β-CYCLODEXTRIN/POLY(DL-LACTIDE) GRAFT COPOLYMERS

Poly(D,L-lactide)-grafted β-cyclodextrin as a biodegradable graft copolymer was synthesized by the ring-opening polymerization of D,L-lactide onto β-cyclodextrin (β-CD) using triethylamine (Et_3N) as the catalyst.The graft copolymers were characterized by means of IR、 ~1H-NMR、DSC、WXRD and GPC measurements.The number average molecular weight was determined and the effect of feed ratio on the graft polymerization was also investigated.The results showed that the graft polymerization of D,L-lactide onβ-CD was successful.The graft ratio (G%) and graft efficiency (GE%) were 182.9% and 21.4%, respectively, when the molar ratio of D,L-lactide to structural glucose unit of β-CD was 30∶1 and the reacting time was 10 hours.Compared with polylactide,the hydrophilicity and biocompatibility of the graft copolymer might be improved by the introduction of β-cyclodextrin units.The obtained graft copolymer would be widely useful in drug delivery systems,tissue engineering and surgical repairs.