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首页> 外文会议>18th International Symposium on Fine Chemistry and Functional Polymers,4th IUPAC International Symposium on Novel Materials and Their Synthesis(第18届国际精细化学和功能高分子学术讨论会暨第四届IUPAC 国际新型材料及其制备学术讨论会） >Synthesis of Aliphatic Polycarbonates via theRing-opening Polymerization of Ethylene Carbonate Catalyzed by Ionic Liquid
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Synthesis of Aliphatic Polycarbonates via theRing-opening Polymerization of Ethylene Carbonate Catalyzed by Ionic Liquid

机译：离子液体催化碳酸亚乙酯的开环聚合合成脂肪族聚碳酸酯

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1.Introduction Aliphatic polycarbonates (APC) has being found wide appilications in polyurethane and surfactant industries because of good biocompatibility and biodegradability. The new process of urea alcoholysis does not rely on the petroleum product (epoxide) and replaces poisonous phosgene to prepare five-membered cyclic carbonate, so it is meaningful to study on the ring-opening polymerization (ROP) of five-membered cyclic carbonate to prepare APC via a green environment protection way. However, cyclic carbonates of the smallest ring (five-membered) e.g ethylene carbonate (EC) hardly undergo ROP in contrast to six-and seven-membered cyclic carbonates. The reason is that molecular structure of five-membered ring is more stable than that of multi-membered ring. The ROP of EC proceeds above 200℃ without catalyst, and involves decarbonation which results in the formation of aliphatic poly(ethylene ether carbonate) (APEC) with contents of EC units below 50 tool%. The synthesis of APEC has been reported in the presence of Lewis acids, transesterification catalysts and bases as initiators or as polymerization catalysts[4], but the reactions needed long time with serious decarbonation. Recently, the use of room temperature ionic liquids as either solvents or catalysts has been the subject of considerable attentions because of the prospects for "green" catalysis.
机译：1.引言脂肪族聚碳酸酯（APC）具有良好的生物相容性和生物降解性，因此在聚氨酯和表面活性剂工业中被发现具有广泛的用途。尿素醇解的新工艺不依赖石油产品（环氧化物），而是代替有毒的光气制备五元环状碳酸酯，因此研究五元环状碳酸酯的开环聚合（ROP）具有重要意义。通过绿色环保方式准备APC。然而，与六元和七元环状碳酸酯相比，最小的环（五元）环状碳酸酯例如碳酸亚乙酯（EC）几乎不经历ROP。原因是五元环的分子结构比多元环的分子结构更稳定。 EC的ROP在没有催化剂的情况下在200℃以上进行，并且涉及脱碳，导致形成EC单元的含量低于50工具％的脂族聚（碳酸亚乙基醚酯）（APEC）。据报道，APEC的合成是在路易斯酸，酯交换催化剂和碱作为引发剂或聚合催化剂的情况下进行的[4]，但反应需要长时间且严重脱碳。近来，由于“绿色”催化的前景，使用室温离子液体作为溶剂或催化剂已成为相当关注的主题。

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