2－甲基－2－甲氧基羰基－5－次甲基－1，3－二氧环戊－4－酮的合成和阴离子聚合

Synthesis and Anionic Polymerization of 2-Methyl-2-methoxy carbonyl-5-methylene-1, 3-dioxolan-4-one

本文报导了一种环状新单体，２－甲基－２－甲氧基羰基－５－次甲基－１，３－二氧环戊－４－酮的合成，并用红外、核磁及元素分析对单体和中间体的结构进行了鉴定．在－７０℃及干燥氮气保护下，用９－芴锂作阴离子５：发剂对此新单体进行了阴离子开环聚合反应的研究．聚合物的红外和核磁谱图表明：在聚合物中存在两种结构单元，这说明在聚合过程中同时存在开环和不开环的两种情况。虽然在聚合物中，这两种结构单元的量应取决于两种相应的碳阴离子的相对稳定性，但是开环聚合在热力学上是有利的，因为开环的结果形成了更稳定的羰基．用粘度法测定了聚合物的特性粘数。

new cyclic monolner, 2-mcthyl-2-methoxy carbony 1-5-methylene- 1, 3-dioxolan-4-one,was synthesixed.The monomer and intermediate were charactcrixed by1H NMR, 13C NMR, INEPTtechniche, IR and elemental analysis.Anionic Polymerization of the rnonomer was carred out carried outin anhydrous THF at -70℃, and 9-fluorenyllithium mps used as initiator, The Polymer strucure was detellmined by IR, NMR and elemental analysis. Molecular weigh of the Polymer was estimated byviscosity measurement in DMSO at 30℃.