圆柱体块共聚物微粒的端到端合和网络形成行为,具有晶体聚烯基芯
Siti F Mohd Yusoff1, Joe B Gilroy, Graeme Cambridge
1School of Chemistry, University of Bristol, Bristol, United Kingdom BS8 1TS.
Journal of the American Chemical Society
|May 28, 2011
概括
将半晶类同聚合物添加到圆柱状的小粒体中,会触发端到端的合,形成网络. 这一对于微粒组装至关重要的过程取决于添加的聚合物.
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:
- 已知圆柱体块共聚合物微粒与晶体聚铁二甲基 (PFDMS) 芯通过表轴生长延长.
- 添加PFDMS块共聚合物单体驱动了这种延长过程.
研究的目的:
- 在添加半晶同聚合物和块共聚合物后,研究圆柱形PFDMS块共聚合物的聚合行为.
- 了解聚合物结晶性和块比在决定小胞聚合途径中的作用.
主要方法:
- 动态光散射 (DLS) 用于总体尺寸分析.
- 传输电子显微镜 (TEM) 用于可视化总体形态.
- 原子力显微镜 (AFM) 用于微粒网络的表面特征.
主要成果:
- 添加半晶 PFDMS ((28) 同聚合物诱导端到端合,形成菌网络,有时核心加厚.
- 无形的PFEMS(25) 没有诱导聚合,而半晶的PFDMG(30) 显示了类似于PFDMS的网络形成,这突显了结晶性的重要性.
- 块共聚合物 (PI-b-PFDMS) 显示出多种聚合:高的冠状核比率导致延长,而较低的比率 (2:1, 1:1) 促进了受控的端到端合和线性结构.
结论:
- 添加的同聚合物的结晶性对于诱导端到端合和小细胞网络形成至关重要.
- 块共聚合物结构,特别是冠状核比率,显著影响聚合途径,较低的比率有利于控制的线性组装.
- 这项研究揭示了通过受控的聚合物添加来创建复杂的菌根架构的可调节策略.
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