在高分子聚合物中,秩序-混乱的转变
Jessalyn Cortese1, Corinne Soulié-Ziakovic, Michel Cloitre
1Matière Molle et Chimie (UMR 7167 ESPCI-CNRS), ESPCI ParisTech, 10 rue Vauquelin 75005 Paris, France.
Journal of the American Chemical Society
|November 15, 2011
概括
这项研究表明,含胺末端组的超分子聚合物表现出秩序-混乱过渡. 在这个过渡温度以上,它们变得无形,但仍然保持结构相关性,影响材料特性.
科学领域:
- 超分子化学 超分子化学
- 聚合物科学 聚合物科学
- 材料科学是一种材料科学.
背景情况:
- 定向相互作用和分散力控制着高分子聚合物组织.
- 研究了带有聚乙烯氧化物 (PPO) 间隔器和胺末组的主链超分子聚合物.
研究的目的:
- 研究主链超分子聚合物的远程顺序和顺序-混乱过渡 (ODT).
- 了解与ODT相关的结构和财产变化.
主要方法:
- 主链超分子聚合物的合成与PPO间隔器和胺末端组.
- 使用X射线散射进行表征.
- 分析热和机械性能.
主要成果:
- 在T下 (ODT),聚合物是半晶体的,具有状结构和纳米相分离.
- 在T(ODT以上,聚合物变得无形和均.
- X射线散射显示T (ODT) 以上的峰值,归因于相关性洞效应.
- 在ODT时,流量和机械性能发生显著变化.
结论:
- 这项研究阐明了这些高分子聚合物中秩序-混乱过渡机制.
- 相关性洞效应影响过渡以上的结构特征.
- ODT极大地影响了宏观材料的行为.
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