编程的热力学形成和结构分析类似恒星的纳米凝,其核心通过可热交换的动态共价键交叉连接
Yoshifumi Amamoto1, Yuji Higaki, Yasuhiro Matsuda
1Graduate School of Engineering, and Institute for Materials Chemistry and Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan.
Journal of the American Chemical Society
|October 4, 2007
概括
类似恒星的纳米凝从具有动态共价键的双块共聚物中以热力学方式形成. 这些纳米凝可以分解回线性聚合物,提供受控的材料特性.
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
- 纳米技术 纳米技术
背景情况:
- 动态共价化学可以使材料对刺激产生反应.
- 控制的聚合物架构对于纳米结构的形成至关重要.
研究的目的:
- 为了研究类似恒星的纳米凝的编程热力学形成.
- 分析这些纳米凝的结构和特性.
- 为了证明纳米凝形成的可逆性.
主要方法:
- 通过原子转移基聚合 (ATRP) 合成双块共聚合物.
- 含有氧胺的共聚物体的热力学交联.
- 使用凝透色谱-多角度激光光散射 (GPC-MALLS),小角度X射线散射 (SAXS) 和扫描力显微镜 (SFM) 的表征.
主要成果:
- 星状纳米凝通过热力学控制的交联反应形成.
- 均衡结构可以根据共聚合物度,组成和分子量进行调整.
- 从纳米凝中再生线性聚合物是通过加热多余的氧胺来实现的.
结论:
- 可实现可逆恒星类纳米凝的编程热力学形成.
- 动态共价键允许控制自组装和拆卸.
- 这种方法为可调节的纳米结构材料提供了一条途径.
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