Synthesis, Properties, and Polymerization of New Liquid Crystalline Monomers for Highly Ordered Guest-Host Systems.

The present study is aimed at the preparation of highly ordered guest-host systerns based in liquid crystalline materials with potential application in the preparation of thin film polarizers. To accomplish this purpose. we carried Out the design, synthesis, and mesomorphic characterization of new reactive liquid crystalline monomers. All the compounds exhibited liquid crystalline behavior The effect Of Structural variations on the mesomorphic properties was investigated. The existence of a highly ordered lamellar phase (S-B) within the mesomorphic behavior of the reactive monomers was confirmed by polarized optical microscopy (POM) and X-ray diffraction (XRD) techniques. Four series of photopolymerisable dichroic mixtures, including a dye (G205) and different percentages of the liquid crystal monomers were prepared. The dichroic ratio DR and order parameter S of the and in the different liquid crystal matrixes were determined by polarized UV-vis spectroscopy in aligned samples. In Situ Photopolymerization of the liquid crystalline mixtures at room temperature ill the Nobly ordered S-B phase resulted in the formation of cross-linked polymeric networks in which the anisotropic absorption of the film was fixed. High dichroic ratio values, exceeding 50, were measured for some of the anisotropic networks. The thermal stability of the anisotropic films obtained was also studied.