近年來，智能材料在致動器的製造中得到了廣泛的應用，在微型機器人、微流體傳輸、傳感器、人造肌肉等領域具有潛在應用。其中，液晶致動器由於液晶取向順序和聚合物網絡結構的彈性相結合而具有獨特的性能。本研究中，通過邁克爾加成反應製造了熱驅動圓柱形液晶彈性體致動器。首先將市售的雙官能基液晶單體RM257、鏈增長劑EDDET、硫醇交聯劑PETMP、光起始劑（Irg184）均勻溶解在甲苯中，然後加入少量稀釋的DPA觸媒進行邁克爾加成反應。第一次聚合後，施加一單軸向拉伸，使液晶彈性體內的分子達到單軸配向，此時多餘的丙烯酸酯再進行光聚合，即可得到單軸配向的液晶彈性體。使用X射線衍射儀 (XRD) ，確認所合成的單軸配向彈性體。所製造的圓柱型液晶彈性體致動器，顯示出可逆的熱驅動縮短/伸長和滾動行為。為了增強近紅外光之靈敏度，將聚多巴胺塗覆在所合成的圓柱型液晶彈性體表面上。塗覆有聚多巴胺的圓柱型液晶彈性體，在近紅外光的照射下可以被驅動。為了開發光能轉機械能再轉電能的二次能量轉換裝置，我們合成了PAAm-LiCl水凝膠，並將其用PDMS封裝組裝成PAAm-LiCl水凝膠摩擦式奈米發電機。我們所製備的摩擦式奈米發電機裝置，使用手接觸拍打時，可產生200伏特的電壓和2.5微安培的電流，並且可以將產生的電能儲存在電容器中。接著，我們將具有塗覆有聚多巴胺的圓柱型液晶彈性體致動器與PAAm-LiCL水凝膠摩擦式奈米發電機結合，設計了一種光能轉換機械，能將光能轉換成機械能再轉換成電能的二次能量轉換裝置。該二次能量轉換裝置可產生2.1伏特的電壓和0.09微安培的電流。最後，我們將二次能量轉換裝置所產生的電能儲存在一個電容器中，所儲存到的電能可以點亮一個綠色發光二極體大約1秒。基於這些結果，發現經由這種設計的圓柱型液晶彈性體致動器與水凝膠摩擦式奈米發電機結合，可應用在二次能量轉換裝置設計，並且可以廣應用於綠色能源技術。

In recent years, smart materials have been widely used in the manufacture of actuators and have potential applications in the fields of micro-robots, micro-fluid transmission, sensors, and artificial muscles. Among them, the liquid crystal actuator has unique properties due to the combination of the liquid crystal orientation order and the elasticity of the polymer network structure. In this study, a series of thermal responsive cylindrical liquid crystal elastomer (CLCE) actuators was fabricated via Michael addition reaction and free radical polymerization. First, commercially available bifunctional liquid crystal monomer RM257, chain extender EDDET, thiol crosslinker PETMP, and photo-initiator (Irg184) were dissolved in toluene, and then a small amount of diluted DPA catalyst was added to carry out Michael addition. After first polymerization, the polydomain CLCE was uniaxial stretched and then photo-polymerized to obtain monodomain CLCE. The synthesized monodomain LCEs were confirmed using X-ray diffractometer (XRD). The fabricated CLCE actuators show reversible thermal responsive shortening-lengthening and a rolling actuation. To enhance near infrared sensitivity, polydopamine (PDA) was coated on the synthesized CLCE surface. The fabricated PDA coated CLCE shows reversible NIR responsive actuations. To develop a photo-mechanical-electrical secondary energy conversion device, PAAm-LiCl hydrogel was used as polymeric electrolyte which was further encapsulated with polydimethylsiloxane (PDMS) and then combined with CLCE actuator for the fabrication of triboelectric nanogenerator (TENG). The fabricated PAAm-LiCl hydrogel TENG shows the generation of a voltage of 200 V with a current of 2.5 μA when the device was activated by hand. The fabricated PDA-coated CLCE actuators was further combined with PAAm-LiCl hydrogel TENG to design a photo-mechanical-electrical secondary energy conversion device. The fabricated secondary energy conversion device shows the generation of a voltage of 2.1 V with a current of 90 nA. The generated electricity was stored in a predesigned capacitor. After a certain period, the stored electricity could light up a green LED for about 1 second. Based on the results, fabrication of secondary energy conversion devices via such designed CLCEs is possible. The predesigned CLCE assisted TENG shows a great potential for the applications in the field of green energy technology.

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