Polylactones, 2 Copolymerization of glycolide with β-propiolactone, γ-butyrolactone or δ-valerolactone†
Polylactones, 2 Copolymerization of glycolide with β-propiolactone, γ-butyrolactone or δ-valerolactone†
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聚内酯，2 乙交酯与 β-丙内酯、γ-丁内酯或 δ-戊内酯的共聚†
DOI：
10.1002/macp.1985.021860507
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发表时间：
1985
影响因子：
2.5
通讯作者：
J. Jonté
中科院分区：
文献类型：
--
作者：
H. Kricheldorf;T. Mang;J. Jonté
乙交酯与β-丙内酯、γ-丁内酯或δ-戊内酯在本体或硝基苯溶液中于20 ~ 150°C的温度范围内进行了许多共聚反应。使用了三类催化剂，即引发阳离子聚合的酸性催化剂、引发插入机制的络合催化剂和阴离子催化剂。共聚酯的摩尔组成由1H NMR谱和共聚单体的序列分布由13 C NMR谱确定。在硝基苯中，在20°C下没有得到乙交酯和β-连苯基丙内酯的合理共聚，而所有催化剂在100°C下都得到共聚酯。在乙交酯/γ-丁内酯的情况下，仅在60°C下用酸性引发剂进行本体共聚是成功的。在其他条件下，只观察到乙交酯的均聚。乙交酯和γ-戊内酯的共聚合在本体和硝基苯中进行，同时使用酸性和络合引发剂，而阴离子引发剂仅引起乙交酯的均聚。酸性引发剂有利于δ-戊内酯的掺入，而络合引发剂有利于乙交酯的掺入。用差示扫描量热法对乙交酯/δ-戊内酯共聚物的结晶度进行了表征，结果与预期的摩尔组成和序列分布吻合较好。
Numerous copolymerizations of glycolide with β-propiolactone, γ-butyrolactone or δ-valerolactone were conducted either in bulk or in nitrobenzene solution at temperatures in the range of 20 to 150°C. Three classes of catalysts were used, namely acidic catalysts initiating cationic polymerizations, complexing catalysts initiating insertion mechanisms, and anionic catalysts. The molar composition of the copolyesters was determined from 1H NMR spectra and the sequence distribution of the comonomers from 13C NMR spectra. No reasonable copolymerization of glycolide and βhyphen;propiolactone was obtained at 20°C in nitrobenzene, whereas all catalysts yielded copolyesters at 100°C. In the case of glycolide/γ-butyrolactone only bulk copolymerizations at 60°C with acidic initiators were successful. Under other conditions only homopolymerization of glycolide was observed. Copolymerizations of glycolide and γ-valerolactone were performed in bulk and in nitrobenzene with both acidic and complexing initiators, whereas anionic initiators only caused homopolymerization of glycolide. Acidic initiators favored the incorporation of δ-valerolactone, whereas the complexing initiators favored the incorporation of glycolide. The crystallinity of the glycolide/δ-valerolactone copolymers was characterized by means of differential scanning calorimetry, and a good agreement with the expectations from both molar composition and sequence distribution was found.