柔性桥联双核卟啉铝催化二氧化碳/环氧化物交替共聚反应  

Flexible Tethered Binuclear Porphyrin Aluminum for the Copolymerization of CO_(2)and Epoxide

作　　者：范培鑫 刘顺杰[1,2] 张若禹 杨列航 高凤翔 陈学思[1,2] 王献红[1,2] Pei-xin Fan;Shun-jie Liu;Ruo-yu Zhang;Lie-hang Yang;Feng-xiang Gao;Xue-si Chen;Xian-hong Wang(Key Laboratory of Polymer Ecomaterial,Changchun Institute of Applied Chemistry,Chinese Academy of Sciences,Changchun 130022;School of Applied Chemistry and Engineering,University of Science and Technology of China,Hefei 230026)

机构地区：[1]中国科学院长春应用化学研究所生态环境高分子材料重点实验室,长春130022 [2]中国科学技术大学应用化学与工程学院,合肥230026

出　　处：《高分子学报》2025年第1期47-57,共11页Acta Polymerica Sinica

基　　金：国家自然科学基金(基金号51988102)资助.

摘　　要：受天然酶启发,协同作用被广泛应用于小分子的识别及其催化转化,但在聚合物合成领域的研究仍然有限.本文报道了一种柔性桥联双核卟啉铝催化剂(FTBC),成功实现了CO_(2)与环氧丙烷(PO)的高效交替共聚.该策略的关键在于通过调控柔性链的长度使得活性位点相互靠近,从而促进分子内协同作用.受益于活性位点的协同效应,以―CH_(2)―为柔性链的C_(1)-Al_(2)表现出优异的催化活性(380 h^(−1))及较高的聚合物选择性(96%),优于相同条件下的单分子卟啉铝(活性为300 h^(−1),聚合物选择性为78%).即使在低催化剂浓度下,C_(1)-Al_(2)也能保持较好催化活性(250 h^(−1)).动力学实验表明C_(1)-Al_(2)反应级数为一级,证实催化剂的分子内协同催化主导共聚过程.本文报道了一种柔性桥联双核催化剂的构筑策略,为模块化设计高性能催化剂提供了新方向.Inspired by natural enzymes,the synergistic effect has been widely applied in small molecule recognition and catalysis,but the exploration of synergy in the field of polymer synthesis is limited.We reported a flexible tethered binuclear porphyrin aluminum catalyst(FTBC),aiming to boost the alternating copolymerization of CO2 and propylene oxide(PO).The key design of FTBC is to promote intramolecular synergy by spatial proximity of active sites through shortening the flexible chains.By shortening the flexible chain length of the FTBC,the catalytic activity of the catalyst gradually increased.The optimal catalyst C_(1)-Al_(2)featured with―CH_(2)―grafting two adjacent aluminum porphyrins exhibits outstanding catalytic activity(380 h−1)and polymer selectivity(96%),outperforming the monomeric catalyst m-Al(300 h^(−1),polymer selectivity%=78%).Benefiting from the intramolecular synergy of C_(1)-Al_(2),the catalytic activity can be maintained at a low catalyst concentration of[PO]/[Al]=20000/1,and the molecular weight of the obtained polymer can reach 48.3 kg/mol.Kinetic studies indicated a first-order dependence on C_(1)-Al_(2)in the copolymerization of CO_(2)/PO,confirming that the intramolecular synergistic catalysis of the catalyst dominates the copolymerization process.Here,we reported a construction strategy for a flexible tethered binuclear catalyst,which opens up a new direction for the modular design of high-performance catalysts.

关 键 词：双核催化剂 铝卟啉 协同催化 二氧化碳 环氧化物 

分 类 号：TQ316.314[化学工程—高聚物工业]