軟性材料近年來在致動器製造上扮演了重要的角色，並展示了其在人造肌肉、軟性機器人和感測器中有前景的應用。在眾多的軟性材料中，由於具備高分子網絡結構和液晶的優選取向，液晶致動器被廣泛使用。本研究中，設計了兩種不同類型的液晶致動器。其一，透過麥克爾加成及光聚合反應製備了一系列的熱敏性柱狀液晶彈性體。此合成的柱狀液晶彈性體可以透過扭轉拉伸使液晶彈性體內部產生不對稱的重心偏移，進而使柱狀液晶彈性體朝特定方向滾動。此彈性體的熱性質及機械性質藉由TGA及DMA來進行鑑定。其二，透過表面定錨效應及光聚合製備了傾斜配向薄膜致動器，當此致動器靠近及遠離熱源時能夠展現可逆性的U型彎曲現象。藉由DSC及TGA的分析，可得知薄膜致動器的玻璃轉換溫度及降解溫度。而薄膜的液晶排列則透過SEM來進行鑑定。為了提高其對近紅外光的敏感度，將其浸入多巴胺溶液中來製備聚多巴胺塗膜層。利用聚多巴胺對近紅外光的光熱效應，薄膜致動器可以有效地將光能和熱能轉換為機械能，並顯現出U型光熱致動行為。最後，將塗覆聚多巴胺的液晶薄膜致動器與銅線結合，設計出了可藉由近紅外光控制的風車。藉由改變近紅外光照射的位置，風車可呈現順時鐘或逆時鐘的旋轉。所合成出之可控方向的柱狀形熱致動器為一項新的技術，為智能性功能材料的製造開闢了一條新的路徑。

Soft materials have recently played an important role in the manufacture of actuators and have demonstrated promising applications in artificial muscles, soft robots, and sensors. Among soft materials, liquid crystalline actuators are commonly employed. In this research, two types of liquid crystal actuators were fabricated by predesigned methods. Firstly, a series of cylindrical thermal sensitive CLCEs was fabricated via a two-step polymerization. The synthesized CLCEs reveal asymmetric constructions showing controllable rolling direction. The CLCEs rolled in controllable specific directions based on the location of the gravity center. Thermal properties and mechanical properties of the synthesized CLCEs were analyzed using TGA and DMA, respectively. Secondary, tilt arranged LCE films were fabricated via alignment layer inductions and photo polymerization. The LCE films exhibit reversible bending when close to and away from the heat source. Based on the results of DSC and TGA, glass transition temperature and degradation temperature of LCE films with tilt-alignment were estimated. The construction of tilt alignment was confirmed using SEM. To enhance the photo sensitivity, the LCE films were soaked into the polydopamine (PDA) solution for three days. Due to the photo-thermal effect of the polydopamine, the synthesized LCE films show U-shape actuations while irradiated with near infrared (NIR). Finally, a NIR responsible windmill was fabricated via the assembly of the PDA-coated LCE films and copper wires. Depending on the irradiation location of NIR, the prepared windmill shows both clockwise and counterclockwise rotations. The creation of direction controllable cylindrical thermal actuators is a novel skill, which opens a new way for the fabrication of smart functional materials.

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