Correlation of structure and phase behaviour for a series of modular, chiral liquid crystal diacrylates based on lactic acid

The mesogenic properties of a family of chiral liquid crystal ( LC) diacryl ates based on a 4-[4-(1R-methyl-2-hydroxyethoxy)phenyl]phenyl 4-hydroxybenz oate core were studied as a function of different tail lengths. In general, this family of LCs was found to exhibit a strong preference for adopting t he chiral smectic A phase. Systematic variation of the alkyl spacer lengths on either side of the chiral core revealed that the onset of smectic A beh aviour is highly sensitive to the length of the tail adjacent to the chiral unit. However, no correlation between phase transition temperatures and th e length of the spacer on the other side of the core was observed. With a f ixed spacer length on the chiral side of the core, systematic changes in th e length of the other tail resulted in the formation of a monotropic smecti c B phase and an increased tendency to supercool.