Synthesis and characterization of liquid crystalline polyacrylates and polymethacrylates containing benzyl ether and diphenyl ethane based mesogens

The synthesis and radical polymerization of a novel series of acrylates and methacrylates containing p‐cyanophenyl‐p‐hydroxybenzyl ether, p‐methoxyphenyl‐p‐hydroxybenzyl ether, and 1‐(p‐cyanophenyl)‐2‐(p‐hydroxyphenyl) ethane groups attached to the polymerizable group through aliphatic spacers containing 11 and 6 methylenic units is described. The resulting polymers were characterized by differential scanning calorimetry and optical polarization microscopy. All polymers exhibited enantiotropic mesomorphism. Low molar mass compounds based on benzyl ether or diphenyl ethane units exhibit only monotropic or virtual transitions. This demonstrates that the “polymer effect” stabilizes mesophases obtained from “mesogenic units” which do not contain rigid interconnecting groups.