Department of Materials Science and Engineering, School of Molecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology (VISTEC), Wangchan, Rayong21210, Thailand.
Inorg Chem. 2022 Dec 19;61(50):20616-20628. doi: 10.1021/acs.inorgchem.2c03532. Epub 2022 Dec 2.
Seven constrained aluminum inden complexes having different substituents and diamine backbones were developed for the ring-opening copolymerization (ROCOP) of epoxides and bulky cyclic anhydrides giving alternating polyesters with ranging from 49 to 226 °C. Among several catalyst/cocatalyst screenings, the aluminum inden complex having a rigid phenylene backbone coupled with 4-dimethylaminopyridine showed the best performance giving linear polyesters. In the case of cyclohexene oxide (CHO) and succinic anhydride (SA), the linear poly(CHO--SA) could be transformed to cyclic polymer when the polymerization was left under prolonged reaction time to induce intramolecular transesterification. The kinetic studies of the ROCOP revealed a zeroth-order dependence on cyclic anhydride and a first-order dependence on epoxide and the catalyst. The catalysts can be extended efficiently to the one-pot CHO/PA/l-lactide terpolymerization giving uncommon tapered copolymers of poly(CHO--PA) and PLA via switchable polymerization.
开发了七种具有不同取代基和二胺骨架的约束铝茚配合物，用于环氧化物和大体积环状酸酐的开环共聚（ROCOP），得到的交替聚酯的玻璃化转变温度（Tg）范围为 49 至 226°C。在几种催化剂/共催化剂筛选中，具有刚性联苯骨架的铝茚配合物与 4-二甲氨基吡啶偶联，表现出最佳性能，得到线性聚酯。在环己烯氧化物（CHO）和琥珀酸酐（SA）的情况下，当聚合反应在延长的反应时间下进行以诱导分子内酯交换时，线性聚（CHO-SA）可以转化为环状聚合物。ROCOP 的动力学研究表明，环状酸酐呈零级依赖，环氧化物和催化剂呈一级依赖。催化剂可以有效地扩展到一锅法 CHO/PA/L-丙交酯三元共聚，通过可切换聚合得到不常见的聚（CHO-PA）和 PLA 锥形共聚物。
