强制展开单链聚合物纳米粒子的强制展开
Nobuhiko Hosono1,2, Aaron M Kushner2, Jaeyoon Chung2
1†Institute for Complex Molecular Systems and Laboratory of Macromolecular and Organic Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands.
Journal of the American Chemical Society
|May 7, 2015
概括
原子力显微镜 (AFM) 和单分子力光谱 (SMFS) 揭示了单链聚合物纳米粒子 (SCPN) 的内部结构. 这种技术量化了超分子组装动力学,提供了对聚合物折叠和自我组装机制的见解.
科学领域:
- 聚合物科学 聚合物科学
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
背景情况:
- 单链聚合物纳米粒子 (SCPNs) 是通过超分子交叉连接的分子内部崩形成的.
- 用2-ureido-4-[1H]-pyrimidinone (UPy) 或-1,3,5-tricarboxamide (BTA) 形成SCPNs的功能化的多烯酸聚合物.
研究的目的:
- 使用AFM-SMFS调查SCPN的内部折叠结构.
- 为了确定SCPNs中超分子自我组装图案的动态参数.
- 为了解SCPN折叠,动力学和组装路径建立一个合理的工具.
主要方法:
- 基于原子力显微镜 (AFM) 的单分子力光谱 (SMFS) 的应用.
- 机械拉伸SCPNs以诱导展开和测量力-延伸配置文件.
- 力量概况的统计分析和动态负载率分析.
主要成果:
- 强度概况显示了明显的峰值,归因于自组装UPy/BTA单元的破裂.
- SCPNs的内部形状受UPy/BTA的合并密度的影响.
- 用动态加载率分析确定了BTA自组装的动态参数,这是一种新的方法.
结论:
- AFM-SMFS为SCPN的折叠结构和内部动态提供了宝贵的见解.
- 该研究展示了一种通过控制UPy/BTA结合来调整SCPN折叠的方法.
- 这项研究为在聚合物系统中超分子自我组装的动力学描述提供了新的途径.
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