热可逆螺旋纤维来自光反应性三烯衍生液晶在液态中的液晶晶体
Takuji Hirose1, Yuka Kikuchi1, Tomoaki Nakano1
1Graduate School of Science and Engineering, Saitama University, 255 Shimo-ohkubo, Sakura, Saitama, 338-8570, Japan.
Heliyon
|December 6, 2023
概括
新的液晶三烯衍生物 (TPC1-n) 在紫外线照射时形成可逆纤维. 这些自我组装的寡合物表明液晶相内的热可逆反应机制.
科学领域:
- 材料科学 材料科学 材料科学
- 有机化学 有机化学
- 超分子化学 超分子化学
背景情况:
- 三烯衍生物以其液晶性质而闻名.
- 照片诱导的转变为新型材料结构提供了途径.
- 液晶中的自我组装可以导致有序的超分子架构.
研究的目的:
- 为了合成新的液晶三烯衍生物 (TPC1-n).
- 为了研究TPC1-n.的照片诱导的结构变化和自我组装行为.
- 阐明光反应产品的反应机制和热可逆性.
主要方法:
- 使用p-alkoxycinnamate进行 [2+2]光循环的TPC1-n衍生物 (n=6,12,14,16) 的合成.
- 在高温 (90°C和110°C) 处在液态抛溶液中对TPC1-n进行紫外线照射.
- 液晶相的表征 (Col_r) 和光反应产物 (纤维) 的形态.
主要成果:
- 具有n=12,14,16的TPC1-n衍生物表现出Col_r液晶相.
- 紫外线辐射诱导由溶液中的TPC1-n形成半月形或螺旋状纤维.
- 光反应产物表现出热可逆性,在高温下溶解,在冷却时重塑,这表明了寡合体的聚合.
结论:
- 合成的TPC1-n衍生物自组装成有序的液晶相.
- 光照射触发了通过寡合化过程形成超分子纤维的过程.
- 光反应产物的观察到的热可逆性与液晶相的固有结构有关.
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