切换具有多个长度尺度的超分子聚合物材料
Ruokolainen1, Makinen, Torkkeli
1J. Ruokolainen and O. Ikkala, Department of Engineering Physics and Mathematics, Helsinki University of Technology, FIN-02015 HUT, Espoo, Finland. R. Makinen, M. Torkkeli, R. Serimaa, Department of Physics, University of Helsinki, Post Office B.
概括
研究人员通过控制相位过渡来创建可调节的聚合物纳米结构. 这些结构表现出温度依赖的电导率,为先进材料提供了潜力.
科学领域:
- 聚合物科学与工程 聚合物科学与工程
- 材料科学 材料科学 材料科学
- 超分子化学 超分子化学
背景情况:
- 聚合物超分子纳米结构提供可调节的层次顺序-失序和顺序-顺序过渡.
- 控制这些转换可以同时切换材料中的功能性质.
- 双块共聚合物为创建复杂的自组装结构提供了一个多功能平台.
研究的目的:
- 为了证明在聚合物纳米结构中对等级的顺序-失序和顺序-顺序过渡的直接定制.
- 通过控制微观结构过渡来研究功能性质,特别是电导性的并发切换.
- 通过使用块共聚合物和超分子复合来实现受控的自我组织结构-结构中的结构.
主要方法:
- 聚4-乙烯化 (P4VP) 与甲硫酸 (MSA) 的固态测量质子化形成P4VP (MSA) 1.0.0.
- P4VP (MSA) 1.0的结合复合与甲基.
- 将MSA和达基复合到微相分离的双块共聚合物聚[styrene-block-(4-vinyl pyridine) 的P4VP块.
- 观察微相分离,重新进入的闭环宏相分离和高温宏相分离.
主要成果:
- 在两个不同的长度尺度 (48和350安格斯特罗姆) 的自我组织结构中的结构中实现对等级阶段过渡的系统控制.
- 通过微观结构控制,证明了通过微观结构控制诱导导电导率的温度依赖转换的能力.
- 观察到各种相位分离行为,包括微相位分离,重新进入的闭环宏相位分离和高温宏相位分离.
结论:
- 聚合物超分子纳米结构具有控制的层次过渡,使可调节的功能性质.
- 开发的方法允许精确控制跨多个长度尺度的自组装结构.
- 这种方法为设计具有可切换电导率的材料提供了一条通路,用于先进的应用.
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