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采用四氢呋喃(THF)和缩水甘油(glycidol)进行阳离子开环共聚,一步合成了主链中含有柔性聚四氢呋喃线型链段的温敏性超支化共聚醚.采用定量13C-NMR确定了共聚醚的超支化结构,同时计算了其支化度.利用体积排除色谱-多角度激光光散射(SEC-MALLS)对聚合物分子量及分布进行了表征.紫外-可见光光谱(UV)测试发现共聚醚水溶液透过率在最低临界溶解温度(LCST)附近呈现剧烈变化,但是其相变速率缓慢,相变平衡时间可达30 min;且聚合物溶液的相变速率和紫外光透过率变化具有温度依赖性.采用透射电镜(TEM)对相变过程观察后发现,这种缓慢相变过程是由于超支化共聚醚组装形成的胶束随温度升高发生不同程度聚集所致.
The temperature-sensitive hyperbranched copolyethers containing linear chain segments of flexible polytetrahydrofuran in the main chain were synthesized in one step by cationic ring-opening copolymerization with tetrahydrofuran (THF) and glycidol.Using quantitative 13C-NMR, the copolyether Hyperbranched structure was obtained and the degree of branching was also calculated.The molecular weight and distribution of the polymer were characterized by volume exclusion chromatography and multi-angle laser light scattering (SEC-MALLS) .Ultraviolet-visible spectroscopy (UV) The overcoatability showed a drastic change near the lowest critical solution temperature (LCST), but its phase transformation rate was slow, and the phase equilibrium time was up to 30 min. The phase transition rate and ultraviolet transmittance of the polymer solution were temperature dependent The observation of the phase change process by transmission electron microscopy (TEM) showed that the slow phase transition was caused by the aggregation of the micelles formed by the hyperbranched copolyether with different temperatures.