Key Laboratory of Biomedical Polymers of Ministry of Education, College of Chemistry and Molecular Science, Wuhan University, Wuhan, Hubei 430072, P. R. China.
Nanoscale. 2018 Nov 7;10(41):19254-19261. doi: 10.1039/c8nr05476b. Epub 2018 Aug 24.
The capability to spatiotemporally regulate polymerization kinetics in response to dual external stimuli of light and magnetism offers exciting pathways to precisely manipulate polymer composition and sequence. Herein, we report a strategy that adopts snowman-shaped FeO@aSiO-click-ZnPTPP Janus nanocomposites with a high magnetization value (12.9 emu g) and stably confined but accessible catalytic metalloporphyrin moieties as the nanocatalysts for photo-induced electron transfer reversible addition-fragmentation chain transfer (PET-RAFT) polymerization. This method enables the synthesis of diverse polymeric structures from a large range of monomers using ultralow concentrations of nanocatalysts (less than 10 ppm) with simple modulation of light and magnetism. In addition, the nanocatalysts are found to be oxygen-tolerant, and they exhibit non-agglomeration during polymerization. Finally, repeated regeneration of the used nanocatalysts by magnetic extraction or facile centrifugation effectively reduces or even eliminates the contamination and/or decomposition on the final polymer products.
采用雪人形 FeO@aSiO-click-ZnPTPP 介孔 Janus 纳米复合材料作为纳米催化剂，该纳米复合材料具有较高的磁化值（12.9 emu g）和稳定但可及的催化金属卟啉基团，可对外界光和磁场的双重刺激做出时空聚合动力学响应，从而为精确调控聚合物组成和序列提供了令人兴奋的途径。本研究报告了一种策略，该策略可用于光诱导电子转移可逆加成-断裂链转移（PET-RAFT）聚合，在该聚合中，可使用低浓度的纳米催化剂（低于 10 ppm），通过简单地调节光和磁场，从各种单体中合成具有不同结构的聚合物。此外，研究发现纳米催化剂具有耐氧性，在聚合过程中不会发生团聚。最后，通过磁萃取或简单的离心可将使用过的纳米催化剂反复再生，有效减少甚至消除最终聚合物产物上的污染和/或分解。
