Study on The Photochemical Properties of Photosensitive Polymer Films and The Induced Orientation of Liquid Crystal Molecules

doi:10.7517/j.issn.1674-0475.2017.01.053

Abstract

Abstract:

In this article, an ultraviolet spectrum method was used to measure the photoreaction property of polymer film containing coumarin photosensitive group. The photochemical reaction property of the film corresponding to the different exposure temperature and the different exposure energy were investigated. The orientation performance of liquid crystal induced by the film at different annealing conditions was also conducted. The results indicate that when the exposure temperature is 130℃, the value of anisotropy ΔA of the polymer film gets to the maximum and the corresponding exposure energy is the minimum. At the same time, the degree of photoreaction is about 45%. When the exposure energy achieve 320 mJ/cm² and 384 mJ/cm², and the annealing temperature is 160℃,the induced value of anisotropy ΔA and order parameter S is 0.22 and 0.048, respectively.

Key words: liquid crystal, annealing, photoreaction, anisotropy

CAO Jin, WU Ti, ZHANG Weimin, WANG Zhanwen, ZHANG Xiaoliang, PU Jialing. Study on The Photochemical Properties of Photosensitive Polymer Films and The Induced Orientation of Liquid Crystal Molecules[J]. Imaging Science and Photochemistry, 2017, 35(1): 53-60.

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