Liquid Crystal Polymer Brush with Hydrogen Bonds:  Structure and Orientation Behavior

Abstract

The structure and properties of the H-bonded liquid crystalline (LC) polymer grafted onto fluorocarbon polymer substrate were studied by the FTIR spectroscopy technique. The grafted LC polymer brush was prepared via “grafting from” polymerization of 4-(6-acryloyloxyhexyloxy)benzoic acid initiated from the surface of UV-irradiated FEP substrate. The orientation under the uniaxial mechanical stress and the temperature behavior of LC brush stabilized by H-bonds were studied. Substantial changes of the structure and orientation of the LC brush were observed upon increase in temperature. The grafting of the LC layer provides the reversible destruction and restoration of the macroscopic orientation. In contrast to the homopolymer, the orientation behavior of grafted H-bonded LC layer is controlled by the fluorocarbon substrate.

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