Saini Prabhjot K, Fiorani Giulia, Mathers Robert T, Williams Charlotte K
Department of Chemistry, Imperial College London, London, SW7 2AZ, UK.
Department of Chemistry, University of Oxford, Chemical Research Laboratory, 12 Mansfield Road, Oxford, OX1 3TA, UK.
Chemistry. 2017 Mar 28;23(18):4260-4265. doi: 10.1002/chem.201605690. Epub 2017 Mar 15.
Developing selective polymerizations from complex monomer mixtures is an important challenge. Here, dinuclear catalysts allow selective polymerization from mixtures of sterically hindered tricyclic anhydrides, carbon dioxide and epoxides to yield well-controlled copoly(ester-carbonates). Surprisingly, two very similar homogeneous catalysts differing only in the central metal, zinc versus magnesium, show very high but diametrically opposite monomer selectivity. The selectivity is attributed to different polymerization kinetics and to steric factors associated with the anhydrides.
从复杂单体混合物中开发选择性聚合反应是一项重大挑战。在此，双核催化剂能够实现空间位阻三环酸酐、二氧化碳和环氧化物混合物的选择性聚合，从而得到可控性良好的聚（酯 - 碳酸酯）共聚物。令人惊讶的是，两种仅在中心金属（锌与镁）上存在差异的非常相似的均相催化剂，却表现出极高但完全相反的单体选择性。这种选择性归因于不同的聚合动力学以及与酸酐相关的空间因素。
