Spontaneous birefringence in films of some phenyl-containing polymers

Spontaneous birefringence in films prepared by free evaporation of a solvent from solutions of sulfated phenyl-containing polymers has been investigated in relation to the thickness of films and the incidence angle of a polarized light beam. It has been demonstrated that not only the value but also the sign of the coefficient of surface birefringence depends on the mode of incorporation of benzene rings into a polymer chain. The structural and orientation factors determining the spontaneous birefringence in the films have been distinguished. The results are compared with the data available for the films of water-soluble polysaccharides. The degree of order in the near-surface layers of polymer films cast from solutions is determined by the statistical segment length of macromolecules and is independent of the chemical nature of chains in the number of water-soluble polymers under consideration.