Nematic Liquid Crystals (NLC) Alignment by the Oriented Nanopatterns of some Polymers Functionalized with Monochlorotriazinyl-[beta]-Cyclodextrin

This paper presents the practical strategies of obtaining the oriented nanostructured surfaces of some polymers functionalized with monochlorotriazinyl-β-cyclodextrin (MCT-β-CD) by two techniques: uniaxial rubbing or linearly polarized UV light (LPUVL) irradiation. We have chosen for the present study polymers and copolymers with exotic behavior with hydroxyl groups allowing the grafting of the reactive product monochlorotriazinyl-β-cyclodextrin or whose pyridinic nuclei can be complexated with MCT-β-CD. The obtained oriented nanostructures align colourless nematic liquid crystals (NLC) or NLC coloured with a dichroic dye. The orientation of NLC has been studied by means of polarized light FT-IR spectroscopy (IR dichroism) and polarized light UV-VIS spectroscopy (VIS dichroism). The initial polymers as well as the chemically modified products have an exotic behavior with regard to the ability of orientating the NLC. The polymers functionalized with MCT-β-CD orientate the NLC perpendicularly to the rubbing direction (or, for photopolymers, perpendicularly to the electrical vector of LPUVL).