INS1-0658
Multi-Borane Lewis Acid Catalyst for Highly Efficient Ring-Opening Polymerization of Epoxides
Topic
S1. Polymer Synthesis
When and Where
Sep 29, 2026
16:40 - 17:05
Room 101
Session Chairs
Chang-Geun CHAE
Presenter(s)
Zhibo Li (Qingdao University of Science and Technology)
Co-Author(s)
Abstract
Organoboranes have recently advanced ring-opening (co)polymerization (ROP) with high controllability, offering diverse polymer structures. Following the pioneering use of BEt3 in ROP, the categories of organoborane have updated to functional borane-based catalysts, borinane, multi-boranes integrated in small organic scaffold or macromolecular framework, which circumvent some limitations of BEt3, such as dilution effect, limited activity and sensitivity to moisture and oxygen. In this study, we tried to incorporate multi-borane Lewis acids. Using tri-, tetra-, and octa-vinyl functional siloxane as core, we prepared tri- tetra- and octa-borane Lewis acids. This design offers high local density and closely positioned active sites targeting high activity for ROP of epoxide. Various initiators combined these multi-borane catalysts and chain transfer agents (CTAs) were investigated to endow diverse structures and molecular weights of polyethers. Density functional theory (DFT) calculations were applied to understanding the mechanism. Given the multi-borane core, a so-called “intramolecular” propagation mode was adopted, and a “self-concentrating synergistic effects” model was proposed to explain the structure–activity relationships. This work provides new designing strategy in creating remarkably active and thermally robust borane catalyst for the ROP of epoxides.
