Phase behaviour of liquid-crystalline copoly(dimethyl-methylhydrogeno)siloxanes substituted with long polar side groups

Abstract The liquid-crystalline properties and structural characteristics of copoly(dimethyl-methylhydrogeno)siloxanes substituted with different proportions of long mesogenic cyano groups are investigated. Comparison is made with the phase behaviour of the chemically related low molecular weight molecules. Some of the unusual features of the polymorphism of these polar compounds are preserved. The compatibility of these copolymers with their low molar mass parents is tested through the study of binary phase diagrams.