Synthesis and characterization of some new main-chain liquid crystalline polymers with tetrakis (oxyethylene) and decamethylene spacers

Polyesters [PhCOOPh(R)OCOPhOX] n (R= H, Me, Et; X= (CH 2 ) 10 , (Ch 2 Ch 2 O) 4 ) were prepared. Both the nature of R and X had a profound influence on the mesogenic prroperties compared to that of the unsubstituted polymer. The methyl substituent increased thez temperature range of the mesophase. The ethyl substituent had a similar effect for the polymer with the decamethylene spacer but its presence led to a marked decrease in the thermotropic properties for the polymer with the poly(oxymethylene) spacer