MOLECULAR CHARACTERISTICS OF POLYMERS WIT H MESOGENIC GROUPS IN THE BACKBONE AND SIDE-CHAINS IN DILUTE-SOLUTIONS

Dilute solutions of a polymer containing mesogenic groups in the backb one and side chains were studied by hydrodynamical, optical, and elect rooptical methods. The dependences of the intrinsic viscosity and the coefficient of translational diffusion on the MM differ from the behav ior observed in linear polymers, which is explained by the presence of long side branches in these molecules. The analysis of the viscosity and diffusivity within the framework of the model of wormlike chain le ads to an abnormally large value (0.8) of the ratio of the chain diame ter to the Kuhn segment. At the same time, the Kuhn segment is (14 - 1 7) x 10(-8) cm, which is typical of the flexible-chain polymers. The o ptical anisotropy per unit length of the polymer molecule (11.6 x 10(- 17) cm2, as estimated from the flow birefringence data) is determined to a considerable extent by optical properties of the backbone. The po sitive Kerr constant of the polymer (4.6 x 10(-12) cm5/(g 300V)) conta ins a positive contribution of the side chains and a negative contribu tion of the backbone. The electrical birefringence in polymer solution s is related to local orientations of the chain fragments, which is du e to high kinetic flexibility of the polymer chains.