Abstract
The three kinds of polyacrylates having the same mesogenic group of p-cyanophenyl benzoate were prepared, which consisted of the different spacer chain; alkylene- (AS), siloxane- (SS) and oligo(ethylene oxide)-spacer (EOS). AS showed two smectic phases, however both SS and EOS exhibited no mesophase. Dielectric relaxation measurements of these polymers were carried out, and the obtained data of dielectric loss was mainly analyzed using Fuoss-Kirkwood function. As the result, it was suggested that the siloxane-spacer and the oligo(ethylene oxide)-spacer were more flexible chains than the ordinary alkylene-spacer, and it would be due to the high flexibility of the spacer chain that no mesophase appeared in SS and EOS.