近年來，以智能材料為主的致動器，由於其在軟性機器人、感測器及人工肌肉領域中具有潛在的應用，因而引起了人們的極大興趣。當接受到外界的刺激時，例如: 熱、光和電場，智能致動器可以表現出可逆的形狀變化。在這些致動器中，液晶高分子彈性體致動器具有獨特的物理性質，因其包含液晶的高秩序性排列及高分子網狀聚合物的彈性性質。本研究中製造了一系列熱驅動液晶致動器，首先準備了含有平行配向層及垂直配向層的玻璃反應槽，然後將市售之液晶單體RM105、聚乙二醇二丙烯酸酯、光啟始劑(Irg184)和雙官能基單體RM257均勻混合後，注入玻璃反應槽內。此液晶混合物的相變溫度，藉由DSC與POM進行鑑定。最後，使液晶混合物在254奈米波長的紫外光照射下，在玻璃反應槽中聚合。當接近或遠離熱源時，聚合後的液晶薄膜展現出可重複操作的的動態彎曲現象。當液晶相轉變時會造成液晶薄膜中分子排列的變化，進而誘導這種可重複運動的彎曲現象。根據此原理，設計了一系列不同的液晶致動器，使高分子膜在熱的驅動下，展示出各種彎曲運動和可承載重物的機械力。聚多巴胺對於紅外光具有優異的光熱轉換效果，藉由塗佈聚多巴胺於表層，製備對紅外光具有高靈敏度的液晶高分子致動器。由實驗結果可知，本研究所製備的液晶致動器，可以有效地將熱能或光能轉換成機械動力。此設計的液晶致動器，期待在人造肌肉和微型機器人系統中具有多種應用潛力。

In recent years, smart materials-based actuators have been attracting much interest because of their envisioned applications in the fields of soft robots, sensors, and artificial muscles. Upon receiving external stimuli (such as heat, light and electrical field), they can exhibit reversible shape changes. Among these actuators, liquid crystalline actuators have unique properties because of combining liquid crystal orientational order with the elastic properties of a polymer network component. In this research, a series of thermal triggered liquid crystalline actuators was fabricated. A glass cell composed of a parallel aligning layer and a perpendicular aligning layer substrates was prepared. A mixture of monomeric RM105, poly(ethylene glycol) diacrylate and photo-initiator Irg-184 with cross-linker RM257 was then injected into the cell. The nematic-isotropic transition temperature of the liquid crystal mixture was estimated using DSC and POM. The liquid crystal mixtures were polymerized in glass cell under 254nm UV irradiation. The polymerized liquid crystalline films show reversible bending motion when close to or away from the heat source. This phenomenon is ascribed to the change of molecular orientation triggered by the variation of order parameters. In view of this, we also designed a series of different LC actuators which show various bending motions and carrying ability under thermal actuation. With the photo-thermal transformation of polydopamine on infrared light, a high sensitive infrared LC actuator doping with polydopamine was fabricated. The observed results suggest that the synthesized LC actuators can effectively transfer thermal and photo energy to mechanical power. These predesigned LC actuators are expected to show a great deal of potential for applications in artificial muscles and micro-robot systems.

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