两亲性带羰基官能团聚己内酯嵌段共聚物的合成与表征

Synthesis and characterization of amphiphilic functional block poly(ε-caprolactonne) bearing ketone groups

将带有羰基官能团的4-羰基己内酯(OPD)和ε-己内酯分别在甲氧基聚乙二醇(MPEG,Mn=5000)为引发剂,异辛酸亚锡为催化剂溶液和本体体系中开环聚合,合成了两亲性侧基带有羰基官能团的聚己内酯嵌段共聚物(MPEG-b-P(OPD-co-CL))。1HNMR结果表明采用溶液聚合法合成的聚合物各峰的峰位置和分裂情况与理论一致,证明了产物是实验所设计的嵌段共聚物,而采用本体聚合法合成的聚合物由于温度的影响,聚合物各峰的峰位置发生了变化,说明其结构发生了变化;差示扫描量热法分析结果表明随着OPD单体含量的增加,聚合物的熔点,玻璃化转变温度和熔融焓增加;热失重测试结果表明OPD单体的引入增加了聚合物的热敏感性。实验结果表明采用溶液聚合可以成功的合成两亲性官能团化聚己内酯嵌段共聚物,而本体聚合由于其反应温度高,所得到聚合物容易发生热降解。

The aim of this study was to develop a novel amphiphilic functional block poiy（ε-caprolactone） bearing ketone groups （MPEG-b-P（OPD-co-CL））. 2-oxepane-1, 5-dione （OPD） was copolymerized with E-caprolatone in which methoxy poly（ethylene glycol） （MPEG, Mn=5 000） and stannous octoate were used as initiator and catalyst, respectively. The syntheses were conducted by bulk and solution polymerization. 1H NMR results showed that peak position and splitting of the polymers synthesized through solution polymerization were consistent with theoretical data, demonstrating the products were designed block copolymers. While in the bulk polymerization, polymer peak position was changed due to their high reaction temperature, suggesting their structural variation. Differential scanning calorimetry analyses indicated that melting temperature, glass transition temperature and enthalpy increased with OPD contents increased in copolymers. Thermogravimetric analysis suggested their enhanced thermosensitivity was attributed to increasing OPD contents. Experimental resulted demonstrate that amphiphilic block poly（^-caprolactone） with functional groups were successfully synthesized by solution polymerization while copolymers obtained by bulk polymerization were easy to degrade due to its high reaction temperature.