Diacetylenic liquid‐crystalline polymers and copolymers. I. Derivatives of diphenyldiacetylene

Abstract

Abstract The diphenyldiacetylene moiety is highly mesogenic and liquid‐crystalline mesophases were observed in polymers incorporating such moieties in the main chain of polyesters with regularly alternating mesogenic groups and flexible spacers. Extensive crystallinity, polymorphism and high values of transition temperatures characterize these polymers. The reactivity of the conjugated triple bond at the temperature of mesophase formation impedes the stability of LC mesophases. Methyl substitution in the benzene ring lowers the transition temperatures significantly.