液晶彈性體具有特殊的物理性質，因其包含液晶的高秩序性排列及高分子網格聚合物的彈性性質。本研究設計並合成了液晶單體M11E、N3E以及含有偶氮結構的圓盤狀液晶D1，與市售之液晶單體RM105、雙官能基單體RM257混合不同比例去製備光驅動液晶彈性體薄膜。此液晶彈性體混合物的相變溫度藉由DSC與POM進行鑑定。偶氮化合物的吸收光譜藉由可見紫外光譜測定，聚合過後的液晶彈性體薄膜在442nm的雷射光源刺激下，展示出可回復的動態彎曲。我們可以觀察到由於高分子中偶氮化合物的E-Z光異構化反應，造成液晶彈性體中分子排列變化從而導致形變的彎曲，進一步地，由於光照導致體積變化量之不同，我們發現薄膜只會向同一方向形變。當移除雷射光，偶氮化合物由Z構型回復到E構型，結果顯示所合成之液晶彈性體薄膜可以高效地將光能轉換為動能，此設計的含感光偶氮衍生物液晶彈性體薄膜未來可以期待被應用於智慧型微形機器人。

The liquid crystal elastomers have unique properties because of combining liquid crystal orientational order with the elastic properties of a polymer network component. To fabricate a light-responsible liquid crystal elastomer film, polymerization of monomeric M11E, N3E, RM105 and a predesigned discotic liquid crystal dopant D1 containing azo groups, mixed with cross-linker RM-257 in different molar ratios was carried out. The transition temperature of liquid crystal mixtures were confirmed using DSC and POM. The absorption spectra was measured using UV-Vis spectrometry. Under the irradiation of 442nm laser beam, the polymerized liquid crystal elastomers show reversible bending motion. This phenomenon is ascribed to the change of molecular orientation triggered by the E-Z photoisomerization of azobenzene derivatives. Furthermore, the sample films bend in a specific direction due to polymer expansion volume difference. After removing of the trigger laser beam, the azo derivatives changed from Z to E leads to the reversed motion of the bended sample film. The results suggest that the synthesized liquid crystal elastomer film can effectively transfer light energy to mechanical power. The predesigned photo-sensitive azo-derivative and the synthesized films are expected to show a number of potential for applications in micro-robotic systems with smart features.

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