AGGREGATION STATE AND MESOPHASE STRUCTURE OF COMB-SHAPED POLYMERS WITH FLUOROCARBON SIDE GROUPS

The aggregation states of a series of comb-shaped polymers with perfluoroalkyl side chains were investigated. The main chains of the comb-shaped polymers were poly(fumarate), poly(acrylate) and poly(methacrylate). D.s.c. and w.a.x.d. measurements and p.o.m. observations over a wide temperature range showed that all the poly(fluoroalkylfumarates) (PFAF) investigated were amorphous polymers, but poly(fluoroalkylacrylate) (PFAA) and poly(fluoroalkylmethacrylate) (PFAMA) having a heptadecafluorodecyl (C8F17) group in the side chain were in a mesomorphic state at room temperature. The type of mesophases can be most likely classified as an ordered smectic liquid crystalline (LC) structure in the Smectic B (S(B)) modification for PFAA and an unordered smectic LC structure in the Smectic A (S(A)) modification for PFAMA. Increasing the main chain flexibility in going from poly(fumarate) to poly(methacrylate) and poly(acrylate) enhances the probability of ordered structure formation.