本研究製備以酯交換反應為原理的熱可調性液晶彈性體，為了讓彈性體具有液晶相，我們以市售液晶單體RM257當作高分子主鏈，並以thiol-acrylate 麥克爾加成反應合成液晶高分子。為了使彈性體在高溫下具有酯交換反應，我們加入鹼性催化劑TBD和單體GDD。
在熱驅動測試和動態機械分析中，彈性體被證實含有液晶的特性，可以在有固定外力的情況下隨著溫度伸長縮短，證明了我們可以藉由外力使高分子中的液晶分子具有排列性。彈性體的熱可調性來自於高分子的共價鍵在高溫下因為鏈交換反應而重排，而在應力緩和測試當中，彈性體在80°C以上具有足夠的應力緩和性質。結果也顯示在沒有羥基的情況下，彈性體依然具有應力緩和的性質，但是效率隨著羥基的量而變好，也隨著溫度和催化劑的量有顯著地增加。
為了使彈性體中的液晶分子排列，我們在高溫下以不同的應力拉伸彈性體，因為高溫下酯交換反應可以使共價鍵重排，所以拉伸過後的排列性可以被固定。在處理過後，液晶彈性體在沒有外界應力的狀態下，具有隨著溫度伸長縮短的性質。

In this study, a series of thermal tunable liquid crystal elastomers (LCEs) showing transesterification bond exchange reaction was fabricated and studied. To create polymer elastomers showing liquid crystal phases, RM257 was used as a main chain liquid crystalline monomer. Monomeric glycerol 1,3-diglycerolate diacrylate and catalyst of triazabicyclodecene (TBD) were introduced to adjust the transesterification reaction at high temperature. From thermal actuation test, the synthesized elastomer shows two-way shape changing with a constant mono-axial stress under the temperature ramping from 0℃ to 75℃, indicating that the monodomain alignment can be achieved by the external mono-axial drawing. In addition, it is well known that the transesterification bond exchange reaction can rearrange the cross-linked covalent bond in the network showing stress relaxation behavior on the polymer network. From the stress relaxation test on DMA instrument, the synthesized LCEs show sufficient stress relaxation behaviors when the temperature is higher than 80℃. Furthermore, the stress relaxation behavior with different amounts of catalyst TBD and monomers having hydroxyl groups was investigated. The result shows that both catalyst amount and hydroxyl containing monomers show significant impacts on the stress relaxation behavior. When the synthesized elastomer was constructed in a specific shape and treated at bound exchangeable temperature, the shape was fixed after cooling down. The constructed shape shows good thermal stability.
When a constant mono-axial stress is applied at bond exchangeable temperature, the synthesized LCE networks may align in the direction of applied stress driving polymer chain and mesogens to align in the same direction. Since the bond exchange reaction can rearrange the covalent bonds in the network, the aligned mesogen state is maintained when the temperature is removed. From shape switching test, after heating the synthesized LCE at 80°C for 90min via a mono-axial drawing, the prepared LCE sample demonstrates thermal reversible shape switching without external mechanical forces.

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