网络重组的动态共价聚合物凝与可交换的diarylbibenzofuranone在环境温度下的网络重组
Keiichi Imato1, Tomoyuki Ohishi, Masamichi Nishihara
1Graduate School of Engineering, Kyushu University , 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan.
Journal of the American Chemical Society
|August 8, 2014
概括
在环境温度下,具有二甲基双黄连接的刺激反应性聚合物凝会在环境温度下重组. 这项研究揭示了微观结构变化与宏观性质一起,使先进材料应用的控制网络重组成为可能.
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
- 超分子化学 超分子化学
背景情况:
- 可逆键使得刺激反应和可重组的聚合物网络具有可回收性和自我修复性等特性.
- 聚合物凝的环境温度重组对于生物医学应用至关重要.
- 以前的研究集中在宏观性质上,忽视了微观结构变化.
研究的目的:
- 在环境温度下系统地研究含有基于二二二 furanone (DABBF) 的动态共价连接的凝网络的重组.
- 在凝网络重组过程中分析宏观和微观变化.
- 了解 DABBF 链接在取决于温度的凝行为中的作用.
主要方法:
- 聚合物凝的合成利用基于二二二 furanone (DABBF) 的动态共价连接.
- 电子偏磁共振 (EPR) 谱学用于研究DABBF链接的平衡.
- 微角X射线散射 (SAXS) 用于分析凝网格大小和网络结构.
- 在各种溶剂和温度下进行胀研究,以观察宏观变化.
主要成果:
- 凝的胀行为取决于温度,在非溶剂中或在室温以下由于DABBF连接平衡而达到平衡胀.
- EPR测量证实了DABBF连接的温度依赖平衡.
- 在环境温度下,SAXS揭示了扩展的网格大小和凝网络结构的受控重组.
- 宏观和微观变化是相关的,提供了对凝重组的全面理解.
结论:
- 基于二甲基双硫 (DABBF) 的动态共价连接在环境温度下促进聚合物凝网络的温度诱导的重组.
- 该研究提供了对刺激响应的聚合物凝行为的显微观理解,将基本的化学变化与可观测的材料特性联系起来.
- 这项工作为设计先进的自我修复和可回收材料奠定了基础,这些材料具有可调节的特性,可用于各种应用,包括生物医学.
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