酶催化己内酯开环聚合及表征

Synthesis and Characterization of Enzyme-catalyzed Ring-openingn Polymerization of ε-caprolactone

通过酶催化聚合法,在无溶剂条件下成功合成了聚e-己内酯,考察了聚合时间、温度、酶量等对反应的影响; 采用红外光谱、1H-NMR谱对聚e-己内酯的结构进行了表征。实验表明,相同酶量下,聚己内酯的分子量先随聚合时间的延长而增大,一定聚合时间后,聚己内酯的分子量趋于定值。己内酯的转化率随聚合时间的延长而升高直至完全转化为聚己内酯。升高反应温度,所得的聚己内酯分子量、转化率都会增大。当酶量不同时,酶量越大,最终得到的聚合物的分子量就越大。

Poly(e-caprolactone) was synthesized by solvent-free enzyme-catalyzed polymerization. The effects of reaction time, temperature and the amount of enzyme on polymerization were studied. The structure of poly(e-caprolactone) was characterized by infrared absorption and 1H-NMR spectrum. The experimental results indicate that, under a constant amount of enzyme, the molecular weight of poly(e-caprolactone) increases to a constant value within some reaction time and then decreases. The conversion of e-caprolactone increases with the reaction time until it transforms completely into poly(e-caprolactone). Temperature is an important factor influencing the polymerization and higher temperature enhances the molecular weight of poly(e-caprolactone) and conversion of e-caprolactone at the range of 55~75C. The molecular weight of poly(e-caprolactone) and conversion of ε-caprolactone also increase with increasing amount of enzyme.