Liquid crystal polycarbonates are made by forming a reaction mixture containing (a) an activated diaryl carbonate; (b) at least two species of aromatic diols selected from among resorcinol, 4,4′-biphenol, hydroquinone, methylhydroquinone, 4,4′-dihydroxyphenylether, dihydroxynaphthalene, including in particular the 2,6, 1,5, and 2,7 isomers, 4,4′-dihydroxybenzophenone and 2,6-dihydroxyanthraquinone (anthraflavic acid); and (c) optionally bisphenol A in a maximum amount of 10 mole %; and processing the reaction mixture in a melt transesterification reaction to form a liquid crystal polycarbonate. While the product composition has the same overall characteristics as compositions made using diphenyl carbonate as the donor moiety for the carbonate linkage, they are analytically distinguishable because of limited incorporation of intermediate or end-cap residues derived from the activated diaryl carbonate.
液晶聚
碳酸酯是通过形成反应混合物来制备的,其中包含(a)活化的二
苯基碳酸酯;(b)至少两种从
间苯二酚、4,4'-联
苯酚、
对苯二酚、甲基
对苯二酚、4,4'-二羟基苯醚、二羟基
萘、特别是2,6、1,5和2,7异构体、4,4'-二羟基苯酮和2,6-二羟基
蒽醌(
蒽黄酸)中选择的芳香族二
酚;以及(c)可选的
双酚A,最大量不超过10摩尔%;并在熔融酯交换反应中处理反应混合物以形成液晶聚
碳酸酯。虽然该产品组成具有使用二
苯基碳酸酯作为
碳酸酯键供体制成的组成物相同的总体特性,但由于活化的二
苯基碳酸酯中间体或端基残留的有限结合,它们在分析上是可区分的。