梯形聚苯基倍半硅氧烷/聚甲基丙烯酸甲酯溶液浇注共混物的相容性

用溶液浇注法制备了具有不同质量配比的高分子量、低分子量梯形聚苯基倍半硅氧烷（ＰＰＳＱ）与聚甲基丙烯酸甲酯（ＰＭＭＡ）的共混物。用扭辫分析技术研究了不同分子量ＰＰＳＱ与ＰＭＭＡ间的相容性及热历史对其相容性的影响。ＰＰＳＱ、ＰＭＭＡ在其溶液浇注膜中是部分相容的。红外光谱分析表明，低分子量的ＰＰＳＱ（Ｙ）与ＰＭＭＡ间有较强的相互作用，故其与ＰＭＭＡ的相容性比高分子量ＰＰＳＱ的好。热历史对该类溶液浇注共混体系的相容性影响较大，加热使ＰＰＳＱ（Ｙ）／ＰＭＭＡ共混物分相，但加热可增加高分子量ＰＰＳＱ与ＰＭＭＡ间的相容性。

MISCIBILITY OF LADDERLIKE POLYPHENYL SILSESQUIOXANE/ POLYMETHYL METHACRYLATE BLENDS PREPARED BY SOLUTION CASTING

Blends of PPSQ with high w or low w and PMMA at different mass ratios had been prepared by solution casting. Miscibility and effect of heat history on the miscibility of these blends had been studied by TBA. The results show that PPSQ and PMMA are partially miscible in their casting blends. The miscibility of PPSQ(Y) with low w and PMMA is better than that of PPSQ with high w and PMMA, because there are some interaction between molecules of PPSQ(Y) and PMMA in the blends indicated by IR. Heat history has some influence on the miscibility of PPSQ(Y)/PMMA or PPSQ/PMMA blends. Heating induce phase separation of PPSQ(Y)/PMMA blends, but it improve the miscibility of PPSQ with high w and PMMA.