摻雜光聚合物液晶盒基板之表面型態研究

Substrate morphology studies of photo-prepolymer-doped liquid crystal cells

崔志宇(Chih-Yu Tsui)

指導教授 ： 黃啟炎

國立彰化師範大學/理學院/光電科技研究所/碩士(2016年)

摘要

本論文探討在不同基板表面、曝光條件及有無磨擦配向的條件下，光聚合物於液晶盒基板表面之聚合型貌。摻雜高分子聚合物NOA65之液晶盒在紫外光曝光期間，聚合物單體受到基板表面及液晶之間的作用力會逐漸往兩側基板進行光感應相分離，最後在基板表面聚合型成微結構。相分離的型態分成等向性相及異向性，取決於基板表面對NOA65的作用力強弱，微結構型態以及曝光條件。同時，微結構的顆粒大小會受到曝光強度支配，上下基板聚合型態的整齊均勻度受到曝光時液晶盒之外加電壓所影響。此外，在塗佈配向膜並進行磨擦配向之液晶盒中，聚合物在基板表面會聚合成平行磨擦配向方向之週期性微結構，此週期性微結構所提供的錨定能足以排列液晶分子。

關鍵字

液晶 ； 高分子 ； 曝光

並列摘要

This thesis investigates the polymer morphology on the substrate surface of the LC cell doped with photo-prepolymer NOA65. The polymer morphology is determined by the surface of the substrate, exposure parameter, and rubbing treatment. During exposure process, the monomers move toward the substrate surfaces due to the photo-induced phase separation induced by the interaction between the LCs, substrate surfaces, and monomers. After polymerization, the microstructures such as gravels and polymer films are formed on the substrate surfaces of the cell. The obtained results also reveal that the photo-induced phase separations can be classified as isotropic and anisotropic phase separations, determined by the extent of the interaction between monomers and substrate surfaces. Furthermore, the polymerization morphology is related to the exposure parameter. It is also found that the polymerized microstructures on the substrate surfaces create periodic structure along the rubbing direction of the LC cell when the substrate is coated with homogeneous or homeotropic polyimide, which can provide sufficient anchoring energy to align the LC molecules. The amplitude and the uniformity of the formed gravels is dependent on the curing intensity and the curing voltage of the LC cell.

並列關鍵字

liquid crystal ； polymer ； curing

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