Ball-Milling-Assisted Silicone Ring-Opening Polymerization for Structure-Controlled Synthesis and Mechanistic Understanding

Functional silicone polymers are widely synthesized through the ring-opening polymerization of cyclic silicone-based monomers. However, conventional bulk polymerization often suffers from viscosity-induced mixing limitations, which can hinder molecular weight control and structural homogeneity, particularly under high-molecular-weight conditions. In this study, mechanochemical ball milling is explored as a solvent-free or low-solvent polymerization strategy to improve mixing efficiency and promote effective contact between cyclic silicone monomers, catalysts, and active chain ends.

The effects of key reaction parameters, including milling frequency, milling time, the number of balls, catalyst species, and liquid-assisted grinding conditions, are systematically investigated in relation to polymerization behavior, molecular weight evolution, and structural uniformity. The applicability of this approach to various substituted cyclic silicone monomers is also examined to evaluate its potential for broadening monomer scope and reducing reactivity disparities. By correlating reaction conditions with polymer structure and material properties, this study aims to establish mechanochemical ring-opening polymerization as a sustainable and efficient platform for structure-controlled silicone polymer synthesis