A Mechanistic Study of the Influence of Oxygen on Free Radical Polymerization of Butyl Acrylate, Vinyl Acetate and Methyl Methacrylate

ABSTRACT In the commercial production of acrylic and vinyl polymers, trace amounts of oxygen can significantly disrupt free‐radical polymerization by generating toxic volatile organic compounds (VOCs), retarding polymerization, and altering polymer properties. To establish a mechanistic understanding of these effects across industrially relevant monomers, this work examines the influence of oxygen on the solution homopolymerizations of butyl acrylate (BA), vinyl acetate (VAc), and methyl methacrylate (MMA). Systematic experiments conducted under nitrogen and air reveal pronounced monomer‐dependent behavior: BA and VAc exhibit severe retardation and form only oligomeric species, while MMA continues to polymerize but shows substantial reductions in molar mass. In all three systems, the presence of oxygen promotes the formation of toxic VOCs, with the extent of oxidation increasing sharply as monomer concentration decreases. To complement the experimental findings, a mechanistic kinetic model is developed for MMA, enabling prediction of monomer conversion, VOC formation, and molecular‐weight evolution under oxygen‐containing conditions. Together, this work provides a unified framework for understanding oxygen‐induced defects in industrial free‐radical polymerization processes involving acrylic and vinyl monomers.