Abstract: Poly (glycolide-co-lactide) (PLGA) with a range of molecular weight was synthesized via a new method of copolymerization of glycolide with L-lactide by using zirconium (Ⅳ) acetylacetonate [Zr (Acac)₄] as initiator. The properties and structure of PLGA were characterized by NMR spectroscopy,differential scanning calormetry (DSC),thermogravimetric analysis (TGA) and X-ray diffraction (XRD). The crystallinity of copolymers obtained was higher than that formed in the presence of traditional catalyst Sn (Oct)₂. The effects of catalyst dosage,polymerization temperature and time were investigated. The optimal condition was as follows:zirconium (Ⅳ) acetylacetonate 0.06%,polymerization temperature 150℃,polymerization time 6h. Intrinsic viscosity of PLGA could reach 0.957dL/g and average molecular weight could reach 1.24×10⁵.

Key words: zirconium(IV) acetylacetonate, glycolide, L-lactide, Poly(glycolide-co-lactide), ring-opening copolymerization, zirconium(Ⅳ) acetylacetonate, glycolide, L-lactide, poly(glycolide-co-lactide), ring-opening copolymerization

摘要： 以乙酰丙酮锆[Zr(Acac)₄]为催化剂引发不同配比的乙交酯和L-丙交酯开环共聚反应,合成出了系列分子量的聚乙丙交酯(PLGA)。采用核磁共振(¹H NMR)、差示扫描量热(DSC)、热重分析(TGA)和X射线衍射(XRD)等方法表征了PLGA的结构和性质。结果表明,以乙酰丙酮锆催化制备的PLGA结晶度高于由传统催化剂辛酸亚锡制备的PLGA。研究了催化剂用量、聚合温度、聚合时间对聚乙丙交酯(PLGA)特性黏度的影响,得出了较优的反应工艺条件为:乙酰丙酮锆用量为0.06%,聚合温度为150℃,聚合时间为6h,合成了特性黏度达0.957 dL/g、重均相对分子质量为1.24×10⁵的高分子量的PLGA。

关键词: 乙酰丙酮锆, 乙交酯, L-丙交酯, 聚乙丙交酯, 开环共聚, 乙酰丙酮锆, 乙交酯, L-丙交酯, 聚乙丙交酯, 开环共聚