SOLUTION BEHAVIOR OF A LIQUID-CRYSTALLINE SIDE-GROUP POLYMER

Dilute and semidilute solutions of fractions of a liquid-crystalline side-group polymer were investigated by means of size-exclusion chromatography (SEC), static light scattering (LS), density and viscosity measurements. The mass-average molar mass ranged from M(w)BAR = 1 . 10(5) g . Mol - 1 to 1,5 . 10(6) g - mol - 1. Large discrepancies were found between the molar mass determined through SEC and through LS. Strong interactions between the mesogenic groups can be assumed by the results of density and LS measurements. Due to the determined characteristic ratio of C(infinity) = 19,5 a similar chain stiffness as a poly(alkyl methacrylate) of equal length of the side chain is observed. In semidilute solutions an excess low-angle scattering (ExLAS) occurs which increases at higher concentrations. The dependence of the reduced osmotic modulus [M(w)BAR/(RT)] (partial-derivative pi/partial-derivative c)T on the parameter x = A2 . M(w)BAR . c was studied.