Preparation and characterization of crosslinked liquid crystalline polymer films as nonlinear optical materials

Liquid crystalline monomers have been synthesized and characterized in purpose to make polymeric second-order nonlinear optical (NLO) materials. Crosslinked polymers have been made to thermally stabilize the orientation created in aligned samples. The orientation has been measured by means of x-ray scattering and infrared dichroism. Oriented, crosslinked poly(vinyl ether)s were made by cationic polymerization whereas crosslinked, nonlinear optical poly(acrylate)s were made by radical polymerization. Polymerization was initiated both thermally and photochemically. The NLO activity of the poly(acrylate)s was measured as the Pockels effect and the second harmonic generation signal, giving values of 0.15 pm/V and 0.40 pm/V, respectively.