Molecular engineering of liquid-crystal polymers by living polymerization. 14. Synthesis and characterization of binary copolymers of .omega.-[(4-cyano-4'-biphenyl)oxy]alkyl vinyl ethers containing undecanyl and hexyl, pentyl and propyl, and undecanyl and propyl pairs of alkyl groups

Abstract

Abstract : Copolymerization represents the simplest synthetic technique which can be used to tailor make phase transitions of both main chain and side chain liquid crystalline polymers. Indeed, copolymerization was frequently employed to manipulate the phase transitions of side chain liquid crystalline polymers. However, most of the results reported in the literature can be considered only in a qualitative way, since there are only very few cases in which information about both copolymer composition and molecular weight are available. A general classification of side chain liquid crystalline copolymers was recently discussed in a review article. There are two main classes of side chain liquid crystalline copolymers. The first one refers to copolymers containing pairs of structural units with and without mesogenic units. This class of copolymers was extensively investigated. The second class refers to copolymers based on pairs of structural units containing mesogenic units in each one.