块共聚合物的结晶驱动的溶液自组装,具有可光分裂的结节
Yang Gao1, Huibin Qiu, Hang Zhou
1School of Chemistry, University of Bristol , Bristol BS8 1TS, United Kingdom.
Journal of the American Chemical Society
|February 6, 2015
概括
响应光的区块共聚合物自组装成圆柱状的片. 在o-nitrobenzyl链接器的光分裂中,聚合物冠状体脱离,使可调节的菌体结构和纳米管形成成为可能.
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
- 纳米技术 纳米技术
背景情况:
- 块共聚合物是具有明显细分的多功能宏分子.
- 块共聚物的自我组装导致有序的纳米结构.
- 响应光的材料提供了对材料属性的动态控制.
研究的目的:
- 合成光敏块共聚合物用于受控自组装.
- 为了研究块共聚合物中特定链接剂的光分离.
- 探索新的纳米结构的形成,如分支和纳米管.
主要方法:
- 合成聚铁二甲基) - 块聚2-乙烯) (PFS-P2VP) 块共聚合物与一个o-尼特罗 (ONB) 光切割结.
- 活体结晶驱动的自组装在选择性溶剂中形成圆柱状.
- 使用紫外线照射对ONB链接器进行光分离.
- 使用显微镜和散射技术对自组装结构的表征.
主要成果:
- PFS-ONB-P2VP块共聚合物形成了单分散的圆柱状.
- 在ONB连接器的光分离中,删除了P2VP冠状体,产生了可调节的剩余冠状体的PFS气.
- 将unimers添加到部分去冠的圆柱体中,导致有分支的小.
- 通过冠状交叉连接合成了可调节长度的几乎单分散的P2VP纳米管.
结论:
- 响应光的区块共聚合物为受控自组装和纳米结构制造提供了一个平台.
- 光切割提供了一个精确的方法来修改菌架构.
- 开发的策略使得复杂的纳米结构,如分支和纳米管的合成.
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