Polymeric dopant effects of bent-core covalent-bonded and hydrogen-bonded structures on banana-shaped liquid crystalline complexes

Abstract

Two series of banana-shaped liquid crystalline (LC) H-bonded complexes HPm/CBn (i.e., bent-core H-bonded side- chain homopolymer HP mixed with bent-core covalent-bonded small molecule CB )a ndCPm/HBn (i.e., bent-core covalent-bonded side-chain homopolymer CP mixed with bent-core H-bonded small molecular complex HB) with various m/n molar ratios were developed. The bent-core covalent- and H-bonded structural moi- eties were homopolymerized in the banana-shaped LC H-bonded complexes HPm/CBn and CPm/HBn, respectively. The influences of m/n molar ratios (polymeric moieties vs. small molecular moi- eties) on the mesomorphic and electro-optical properties of both banana-shaped LC H-bonded complexes HPm/CBn and CPm/HBn were investigated. The polar smectic phases could be achieved and stabilized by smaller contents of polymeric dopants in ba- nana-shaped LC H-bonded complexes, such as HP1/CB10, HP1/ CB15, CP1/HB10 ,a ndCP1/HB15, which possessed tunable spon- taneous polarization (Ps) values according to the molar ratios of m/n ,t hat is, lowerPs values obtained in H-bonded complexes HPm /CBn and CPm / HBn with higher ratios of H-bonded moieties (larger m/n molar ratios), respectively. V C 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 764-774, 2010