Ghosh Goutam, Dey Pradip, Ghosh Suhrit
School of Applied and Interdisciplinary Sciences, Indian Association for the Cultivation Science, 2A and 2B Raja S. C. Mullick Road, Kolkata, 700032, India.
Chem Commun (Camb). 2020 Jun 23;56(50):6757-6769. doi: 10.1039/d0cc02787a.
Supramolecular polymers, albeit having precise internal order, largely lack precision in the mesoscopic scale because in most examples supramolecular polymerization occurs under thermodynamic control through spontaneous self-assembly. Recent reports have exemplified that by varying experimental parameters including cooling rate, solvent composition, interplay of intra- vs. inter-molecular H-bonding and others, it is possible to retard the spontaneous nucleation, and isolate a dormant kinetically controlled monomeric/aggregated state which in turn can serve as the monomer pool to undergo controlled supramolecular polymerization (CSP) through a chain-growth mechanism in the presence of an aggregated/molecular initiator (seed) or by an external stimuli like light. Supramolecular polymers with narrow dispersity, predictable length or stereo-selectivity have been achieved by CSP. Chain extension (similar to "living" polymerization) in such seed initiated CSP is now possible by batch wise addition of monomers, allowing synthesis of supramolecular block copolymers. This feature article describes recent developments in CSP (primarily under kinetic control) of various π-conjugated building blocks.
超分子聚合物尽管具有精确的内部秩序，但在介观尺度上大多缺乏精确性，因为在大多数情况下，超分子聚合是在热力学控制下通过自发自组装发生的。最近的报道表明，通过改变包括冷却速率、溶剂组成、分子内与分子间氢键的相互作用等实验参数，可以延缓自发成核，并分离出一种休眠的动力学控制的单体/聚集态，该状态进而可以作为单体库，在聚集/分子引发剂（种子）存在下或通过光等外部刺激，通过链增长机制进行可控的超分子聚合（CSP）。通过CSP已经实现了具有窄分散性、可预测长度或立体选择性的超分子聚合物。通过分批添加单体，现在可以在这种种子引发的CSP中进行链增长（类似于“活性”聚合），从而合成超分子嵌段共聚物。这篇专题文章描述了各种π共轭结构单元在CSP（主要是在动力学控制下）方面的最新进展。
