渐变结晶驱动的自组装:通过线性和刷块共聚合物的联合组装,具有"不齐"细分冠状的圆柱状小粒
John R Finnegan1, David J Lunn, Oliver E C Gould
1School of Chemistry, University of Bristol , Bristol BS8 1TS, United Kingdom.
Journal of the American Chemical Society
|September 23, 2014
概括
研究人员在区块共聚合物中实现了活梯度结晶驱动的自我组装 (CDSA). 这一过程通过控制刷长度和与线性聚合物一起组装,在米塞尔中创建渐变结构,类似于渐变共聚合,通过控制刷长度和与线性聚合物一起组装.
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:
- 区块共聚合物 (BCP) 在选择性溶剂中自组成明确的纳米结构.
- 活体结晶驱动自组装 (CDSA) 允许这些纳米结构的受控生长.
- 结晶刷BCP提供独特的自组装特性,因为它们的刷状侧链.
研究的目的:
- 为了研究不同的n-基分支长度的晶体刷BCP的CDSA.
- 探索刷子BCP与线性BCP的共同组装,以克服生长限制.
- 为了实现与梯度结构的块漫画的受控合成.
主要方法:
- 合成聚铁二甲基) 块聚甲基氧) (PFS-b-PMVS) 刷子BCP.
- 乙烯功能化引入不同长度的n-基分支 (C6,C12,C18).
- 由种子菌引发的活体CDSA,涉及与线性PFS-b-PMVS一起组装.
- 使用传输电子显微镜 (TEM) 和原子力显微镜 (AFM) 进行表征.
主要成果:
- 增加的n-基刷长度阻碍了菌的生长,但与线性PFS-b-PMVS的联合组装减轻了硬质障碍.
- 形成了具有可控制长度和"不整"的冠状纳米域的单分散块漫切尔.
- TEM和AFM提供了关于组装的米塞尔的补充结构信息.
- 观察到一个梯度结构,有线BCP的优先增长,其次是刷BCP.
结论:
- 在区块共聚合物中展示了第一个活梯度CDSA的例子.
- 梯度结构来自于不同的unimer添加率和刷子块的固体效应.
- 这种方法可以精确控制区块漫画架构,模仿梯度共聚合.
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