本論文乃首次製備出全聚合式布拉格洋蔥狀膽固醇液晶彈性體微球，研究此彈性體微球之可熱與可光調控反射特性與構型大小。實驗製備取消了過去常用的有機溶劑萃取步驟，改用可全聚合材料來製備膽固醇液晶彈性體微球，可大幅提升膽固醇液晶彈性體微球的製備良率與大量減少製程時間。
本論文之膽固醇液晶彈性體微球具備橡膠的彈性伸縮特性與膽固醇液晶的螺旋自組裝有序性，藉由熱與光調控，觀察與探討彈性體微球的反射特性與球體構型大小的變化。在熱調控方面，於加溫過程觀察到膽固醇液晶彈性體微球於玻璃態轉換成橡膠態時的差異，當處於橡膠態升溫過程時，彈性體微球高分子網絡整體結構鬆軟，高溫致使高分子側鏈被擾亂而造成整體彈性體微球體積變大而螺距變長，致使中心結構色有明顯紅移現象發生且反射率下降。在光調控方面，透過UV光的照射，使得處於橡膠態的彈性體微球內主鏈上的偶氮苯發生光致異構化反應，偶氮苯由棒狀trans態轉變成彎曲狀cis態時，眾多彎曲狀cis態分子擾動彈性體微球內高分子主鏈，使得整體彈性體微球體積變大而螺距增加，反射色紅移且反射率下降。此研究成功製備全聚合式膽固醇液晶彈性體微球，並獲得其可熱與可光調控光學反射特性與尺寸大小之資訊，未來可與實驗室長期投入的光渦流光鉗控制系統做結合。

This thesis first fabricated fully-polymerized Bragg-onion-like cholesteric liquid crystal elastomer (CLCE) microdroplets and investigated the optical and thermal tunabilities of their structural color and configuration. To effectively improve the yield for preparing elastomer microdroplets and reduce the production time, a full-polymerization method was used to replace the extraction/backfilling method used in the past.
In the study, the fabricated CLCE microdroplets have both properties of elasticity of rubber and orderliness of spiral self-assembly. Through thermal and optical control, we can simultaneously observe the changes in the structural color and configuration of the CLCE droplets. In terms of thermal tunability, the CLCE droplets can transform from glassy state to rubbery state by heating through the glass transition temperature (Tg). During the heating process in the rubbery state, the polymer network structure of the elastomeric microsphere is relatively soft so that heating can cause the polymer side-chains to be disturbed, causing the microsphere to become larger and the pitch longer, resulting in a red-shift in the structural color and the decrease of the reflectivity. In terms of optical tunability, the irradiation of UV light can induce the azobenzene moieties on the main-chains of the polymer network to undergo tran-cis photoisomerization. This effect can isothermally disturb the polymer main-chains of the network at the rubbery state, where the temperature is slightly higher than Tg, and thereby cause the increase of the droplet volume and the elongation of the pitch, leading to the red-shift of the structural color and the decrease of the reflectivity. The 3D CLCE microspheres are highly sensitive to external parameters, which is helpful for applications associated with microsensors.

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