精确定义的液晶凝来自远程合物聚合物
Yan Xia1, Rafael Verduzco, Robert H Grubbs
1Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA.
Journal of the American Chemical Society
|January 17, 2008
概括
研究人员使用点击化学和环开放转化聚合 (ROMP) 制造了新的液晶 (LC) 凝. 这些LC凝表现出快速,可逆的光学切换,性能受到聚合物链长度的影响.
科学领域:
- 聚合物化学 聚合物化学
- 材料科学 材料科学 材料科学
- 液晶是一种液晶.
背景情况:
- 液晶 (LC) 网络是具有可调节性质的先进材料.
- 控制诸如分子量和交叉连接功能的网络参数对于优化LC凝性能至关重要.
- 环开放元解聚合 (ROMP) 提供了一条通往明确的聚合物前体的途径.
研究的目的:
- 合成精确定义的液晶网络,精确控制分子架构.
- 研究通过膨胀这些网络形成的液晶凝 (LC凝) 的形成和特性.
- 探索LC凝的电光切换行为及其对网络结构的依赖.
主要方法:
- 通过环开放型转化聚合物 (ROMP) 制备远性聚合物.
- 电介质聚合物的"点击"交叉链接形成液晶网络.
- 在5CB (一个小分子液晶) 中膨胀网络,以创建LC凝.
- 在应用电场下评估光学切换特性.
主要成果:
- 成功合成了精确定义的LC网络,在交叉链接和交叉链接功能之间控制了分子量.
- LC凝呈现出高膨胀率,并显示出快速,可逆,低值的光学切换.
- 在LC凝中,较短的聚合物链导致光学切换的程度降低,而较长的链则降低.
- 这项研究确定了对中位子密度和网络链长度的控制.
结论:
- 开发的方法可以精确控制LC网络的关键参数,包括链条长度,交叉连接器功能和中介质密度.
- 这种控制有助于对LC网络中的结构-属性关系进行详细研究.
- 这些发现有助于对液晶凝的科学理解和技术应用.
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