Ring-Opening Co- and Terpolymerization of Epoxides, Cyclic Anhydrides, and l-Lactide Using Constrained Aluminum Inden Complexes

Nattiya Laiwattanapaisarn; Arnut Virachotikul; Phongnarin Chumsaeng; Tiphanan Jaenjai; Khamphee Phomphrai

doi:10.1021/acs.inorgchem.2c03532

Ring-Opening Co- and Terpolymerization of Epoxides, Cyclic Anhydrides, and l-Lactide Using Constrained Aluminum Inden Complexes

Inorg Chem. 2022 Dec 19;61(50):20616-20628. doi: 10.1021/acs.inorgchem.2c03532. Epub 2022 Dec 2.

Authors

Nattiya Laiwattanapaisarn¹, Arnut Virachotikul¹, Phongnarin Chumsaeng¹, Tiphanan Jaenjai¹, Khamphee Phomphrai¹

Affiliation

¹ Department of Materials Science and Engineering, School of Molecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology (VISTEC), Wangchan, Rayong21210, Thailand.

PMID: 36459655
DOI: 10.1021/acs.inorgchem.2c03532

Abstract

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 T_g 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-alt-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-alt-PA) and PLA via switchable polymerization.