一种可治愈的高分子聚合物混合物,基于芳香的pi-pi堆叠和结合相互作用
Stefano Burattini1, Barnaby W Greenland, Daniel Hermida Merino
1Department of Chemistry, University of Reading, Whiteknights, Reading RG6 6AD, UK.
Journal of the American Chemical Society
|August 12, 2010
概括
这项研究引入了一种新的可治愈的聚合物混合物. 这种高分子材料结合了聚胺和聚氨,通过pi-pi堆叠和结合表现出了显著的自我愈合特性.
科学领域:
- 聚合物科学 聚合物科学
- 材料化学 材料化学
- 超分子化学 超分子化学
背景情况:
- 开发具有自我愈合能力的先进弹性体材料对于延长材料寿命和减少浪费至关重要.
- 超分子相互作用提供了一个有前途的途径,可以在没有共价交联的情况下创建内在可治愈的聚合物.
研究的目的:
- 通过超分子相互作用创建一个坚固,弹性和可治愈的聚合物混合物.
- 调查pi-pi堆叠和键在使聚合物混合物兼容的作用.
- 描述开发的材料的形态和自我愈合效率.
主要方法:
- 一种聚合物混合物的合成,其中包括一个链式折叠聚胺和一个具有烯基末端组的远程聚氨.
- 可变温度里埃变换红外光谱 (FTIR) 用于分析聚合物间相互作用.
- 可变温度小角度X射线散射 (SAXS) 来研究形态学.
- 机械测试用于评估骨折后自我愈合效率.
主要成果:
- 一种超分子聚合物混合物成功地制造出来,表现出弹性质和可治愈性质.
- 聚胺二胺和烯基单位之间的芳香pi-pi堆叠,以及结合,被证实是关键的兼容机制.
- 可变温度SAXS揭示了纳米相分离形态与温度依赖域对比.
- 破碎的样品显示了机械性能的显著恢复,恢复了超过95%的拉伸模量和77%的性.
结论:
- 开发的聚合物混合物展示了出色的性和自我愈合能力,归因于协同的超分子相互作用.
- 该材料的纳米相分离形态学有助于其强大的机械性能和愈合效率.
- 这项工作为设计具有可调节性质的先进可愈合材料提供了途径.
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