Deng Renhua, Mao Xi, Pearce Samuel, Tian Jia, Zhang Yifan, Manners Ian
School of Chemistry, University of Bristol, Bristol BS8 1TS, U.K.
Key Laboratory of Material Chemistry for Energy Conversion and Storage of Ministry of Education, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China.
J Am Chem Soc. 2022 Oct 19;144(41):19051-19059. doi: 10.1021/jacs.2c07962. Epub 2022 Oct 6.
Low dispersity 2D platelet micelles with controllable surface patterns were prepared by seeded-growth/living crystallization-driven self-assembly (CDSA) of block copolymer/homopolymer (BCP/HP) blends of poly(ferrocenyldimethylsilane)--poly(2-vinyl pyridine) (PFS--P2VP) and PFS. The precise morphology was found to be dependent on the proportion of the P2VP corona block, which can be efficiently controlled by changing the molar concentration ratio of PFS--P2VP/PFS, (/), as well as their relative rates of crystallization, (/). In the case where their molar concentration ratio was comparable to their crystallization rate ratio, platelets with a uniform distribution of P2VP coronal chains were formed. In other cases, as the concentration ratio increased (or decreased) during the living CDSA process, hierarchical structures were formed, including chain-like assemblies consisting of end-to-end linked rectangular platelets and fusiform (tapered) micelles. (/) was adjusted by tuning the degree of polymerization of the crystallizable PFS core-forming block and the BCP block ratio and by varying the terminus of the HP or changing the solvent used. Furthermore, the open edge of the platelets remained active for further growth, which permitted control of the morphology and dimensions of the platelets. Interestingly, in cases where the molar concentration ratio was lower than the crystallization rate ratio, growth rings were observed after two or more living CDSA steps. This study on the formation of platelet micelles by living CDSA of BCP/HP blends under kinetic control offers a considerable scope for the design of 2D polymer nanomaterials with controlled shape and surface patterns.
通过聚（二茂铁二甲基硅烷）-聚（2-乙烯基吡啶）（PFS-P2VP）和PFS的嵌段共聚物/均聚物（BCP/HP）共混物的晶种生长/活性结晶驱动自组装（CDSA）制备了具有可控表面图案的低分散二维片状胶束。发现精确的形态取决于P2VP冠嵌段的比例，这可以通过改变PFS-P2VP/PFS的摩尔浓度比（/）以及它们的相对结晶速率（/）来有效控制。当它们的摩尔浓度比与其结晶速率比相当时，形成了P2VP冠状链均匀分布的片状胶束。在其他情况下，随着活性CDSA过程中浓度比的增加（或减少），形成了分级结构，包括由端对端连接的矩形片状胶束和梭形（锥形）胶束组成的链状组装体。通过调节可结晶的PFS核形成嵌段的聚合度和BCP嵌段比，以及改变均聚物的端基或改变所用溶剂来调节（/）。此外，片状胶束的开放边缘保持活性以进一步生长，这允许控制片状胶束的形态和尺寸。有趣的是，在摩尔浓度比低于结晶速率比的情况下，经过两个或更多个活性CDSA步骤后观察到生长环。这项关于在动力学控制下通过BCP/HP共混物的活性CDSA形成片状胶束的研究为设计具有可控形状和表面图案的二维聚合物纳米材料提供了相当大的空间。
