Study on the Relations of Structure and the Ultrafast Optical Kerr Effect of Polynitriles

A series of polybenzonitrile derivatives, prepared by plasma glow discharge processes or chemical polymerization, were characterized by FT-IR, UV-Vis, GPC and VPO etc. The secondorder nonlinear optical hyperpolarizability γ of various benzonitrile monomers and their, polymers were measured by the femtosecond time-resolved optical Kerr effect technique, and the structureproperty relationships were discussed. The power law dependence of γ on the averagepolymerization- degree of several polybenzonitrile derivatives were also reported.