An Investigation of the Coupling Reaction between Living Ring-Opening Metathesis Polymerization (ROMP) Linear Polymers with Multi-functional Coupling Agents through the Synthesis of Well-Defined Star Polymers

Abstract

This thesis aims to investigate the coupling reaction between living Ring-Opening Metathesis Polymerization (ROMP) polymer and multi-functional aldehyde coupling agents through the synthesis of well-defined Mo-based ROMP star polymers. The coupling reaction can be described by its kinetics (rate at which living arm adds to the multi-functional aldehyde coupling agent) and its efficiency (yield of star product). The investigation begins with a focus on the simplest coupling reaction between two arms with di-aldehyde coupling agents for form star polymers with functionality, f = 2. The ability to characterize the reaction kinetics with the simplest star polymer can be extended to characterize the coupling reaction with higher-order functionality ROMP star polymers, namely f = 3 and f = 4 that were synthesized in this study. In general, the coupling kinetic is observed to be affected by a combination of electronic and steric factors inherent in the multi-functional coupling agent. The yield can be maximized by careful experimental procedures to deliver stoichiometrically accurate amounts of coupling agent to the living polymer.