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以聚乙二醇(PEG-400)、环氧氯丙烷为原料,氢氧化钾为缚酸剂,十六烷基三甲基溴化铵为相转移催化剂制得聚乙二醇缩水甘油醚(epoxide-PEG-epoxide)。然后,在氢氧化钠水溶液中,聚乙二醇缩水甘油醚中的环氧键水解生成分子链两端各含有两个羟基的大分子引发剂((HO)2PEG(OH)2)。最终,以辛酸亚锡为催化剂,端羟基大分子引发剂引发ε–己内酯开环聚合,合成了不同相对分子质量的H型两亲性嵌段共聚物((PCL)2PEG(PCL)2)。通过红外光谱(FTIR)和核磁共振氢谱(1H-NMR),聚乙二醇缩水甘油醚,端羟基大分子引发剂和H型两亲性嵌段共聚物的结构得到了确认。示差扫描量热法对两亲性嵌段共聚物热性能的研究表明:当亲水段的聚乙二醇分子量为400时,聚合物的熔融温度主要受疏水段的聚己内酯影响,随着聚己内酯链段长度的增加,熔融温度升高。
Using polyethylene glycol (PEG-400) and epichlorohydrin as raw materials, potassium hydroxide as acid-binding agent and cetyltrimethylammonium bromide as phase-transfer catalyst, polyethylene glycol glycidyl ether epoxide-PEG-epoxide). Then, in an aqueous solution of sodium hydroxide, the epoxy bonds in the polyethylene glycol glycidyl ether are hydrolyzed to produce a macroinitiator ((HO) 2PEG (OH) 2) containing two hydroxyl groups at both ends of the molecular chain. In the end, with the stannous octoate as the catalyst, the terminal hydroxyl-terminated macromolecular initiator initiated the ring-opening polymerization of ε-caprolactone to synthesize the amphiphilic H-type amphiphilic block copolymer (PCL) 2PEG ). The structures of polyethylene glycol glycidyl ether, hydroxyl-terminated macromolecular initiator and H-type amphiphilic block copolymer were confirmed by FTIR and 1H-NMR. Differential scanning calorimetry of amphiphilic block copolymer thermal properties of the study showed that: when the hydrophilic polyethylene glycol molecular weight of 400, the melting temperature of the polymer is mainly affected by hydrophobic segments of polycaprolactone, with Polycaprolactone segment length increases, the melting temperature increases.