The effect of structural changes in the molecular core and periphery on the liquid-crystalline properties of some chiral 4-n-alkoxyphenylpropiolates

Abstract The thermotropic liquid-crystalline properties of several homologous series of chiral 4-n-alkoxyphenylpropiolates were correlated with chemical structural modification on the periphery of the rigid, aromatic, molecular core. The temperature ranges of the most disordered mesophase in each series were shown to be inversely proportional with respect to the number of carbon atoms in the terminal alkoxy moiety. The type of mesophase exhibited by an homologous series is determined by the number of carbons in the chiral alkyl substituent. Homologous series containing short chain chiral alkyl substituents formed mesophases that had higher degrees of disorder (i.e. cholesteric phases) than did those that contained long chain chiral alkyl substituents.