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通过溶剂诱导结晶的方法研究了梯形苯基聚倍半硅氧烷(PPSQ)的球晶结构. 采用光学显微镜研究了溶液的浓度、溶剂的挥发时间以及温度等影响因素对梯形苯基聚倍半硅氧烷的球晶结构形貌的影响. 实验结果表明:稀释溶液浓度与提高结晶温度在改变球晶的形态方面具有相同的效果. 球晶的尺寸会随着溶液浓度的降低或者结晶温度的升高而增加. 这都归因于梯形苯基聚倍半硅氧烷在二甲苯中的溶解度的增加. 在不改变其它结晶条件的情况下,延长溶剂的挥发时间也会形成更大的球晶. 当在光学显微镜下旋转样品时球晶的结构不会发生改变,这表明球晶具有均一的晶体学取向结构. 负性球晶的特征也表明梯形苯基聚倍半硅氧烷的分子链是沿着球晶的切线方向排列. 考虑到梯形苯基聚倍半硅氧烷具有刚性的分子链,还提出了梯形苯基聚倍半硅氧烷可能的球晶结构模型.
The spherulitic structure of PPSQ was studied by means of solvent-induced crystallization.The effects of the concentration of the solution, the volatilization time of the solvent and the temperature on the spherulitic polyphenylsilsesquioxane The experimental results show that the concentration of dilute solution has the same effect as the increase of crystallization temperature in changing the morphology of spherulites.The size of spherulites decreases with the decrease of solution concentration or the crystallization temperature Due to the increased solubility of the trapezoidal phenylpolysilsesquioxane in xylene.Improving the volatilization time of the solvent also results in a larger ball without changing other crystallization conditions Crystal. The structure of the spherulites does not change when the sample is rotated under an optical microscope, indicating that the spherulites have a uniform crystallographic orientation structure.The negative spherulitic features also indicate that the molecules of the trapezoidal phenyl polysilsesquioxane The chains are aligned along the tangential direction of the spherulites.According to the rigid molecular chains of the trapezoidal phenyl polysilsesquioxanes, possible spherulitic structural modes of the trapezoidal phenylsilsesquioxanes have also been proposed .