Mesomorphic and Orientational Study of Materials Processed by In Situ Photopolymerization of Reactive Liquid Crystals

Abstract

The synthesis and in situ photopolymerization of reactive liquid crystals for the preparation of materials with different degrees of cross-linking is described. The molecular orientation of polymeric films can be controlled by orienting the monomeric photopolymerizable materials in the mesomorphic state. The birefringence of photopolymerizable materials and the resulting polymers are described, and its dependence on the temperature has been evaluated. The degree of order of polymeric films has been studied by using a reactive nitrostilbene unit as a probe for performing dichroism measurements. Polymeric films with a low degree of cross-linking showed a memory effect, as observed by optical microscopy, X-ray diffraction, and birefringence measurements.