SYNTHESIS AND CHARACTERIZATION OF SIDE-CHAIN LIQUID-CRYSTALLINE POLYSILOXANES CONTAINING 4-ALKANYLOXYPHENYL TRANS-4-ALKYLCYCLOHEXANOATE SIDE GROUPS

Abstract

The synthesis and characterization of nine polysiloxanes containing 4-alkanyloxyphenyl trans-4-n-alkylcyclohexane side groups are described. Six monomers which contain a pentenyloxy or a hexenyloxy flexible spacer display a nematic mesophase, while the other three monomers which contain an undecenyloxy flexible spacer display nematic, smectic A and smectic E mesophases. All synthesized polymers present two smectic mesophases except one containing 4-hexanyloxyphenyl trans-4-n-butylcyclohexanoate side groups presents one smectic mesophase and one containing 4-undecanyloxyphenyl trans-4-n-pentylcyclohexanoate side groups presents three smectic mesophases. Trans-cis isomerization of mesogens and side chain crystallization did not occur for any of the synthesized polymers.