In the present study an experimental and theoretical investigation on the styrene/2‐ethylhexyl acrylate emulsion copolymerization is reported. Kinetic experiments were carried out in a laboratory batch reactor, to analyze the effects of the initial styrene mole fraction, non‐ionic surfactant, and initiator concentrations on the reaction kinetics, copolymer composition and particle size distribution of the latex. All kinetic experiments were run through the full conversion. A comprehensive mathematical model was developed to describe the dynamic behavior of the styrene/2‐ethylhexyl acrylate batch emulsion copolymerization. The model includes a detailed kinetic mechanism, the thermodynamics of the emulsion mixture, dynamic molar species balances in the polymer and aqueous phases, the rate of particle formation, and growth and diffusion controlled phenomena. Detailed dynamic species mass balances are derived to follow the evolution of the particle nucleation rate, total number of particles, polymerization rate and particle size distribution in a batch reactor. The proposed particle nucleation mechanism accounts for both homogeneous and micellar particle nucleation. The capabilities of the present model are demonstrated by comparison of model predictions with the experimental data on conversion and particle size distribution (PSD). It is shown that the model is capable of correctly reflecting the time evolution of conversion, particle size and PSD over substantial variations of the process operating conditions.Comparison of model predictions and experimental measurements on average particle size.magnified imageComparison of model predictions and experimental measurements on average particle size.

A comprehensive mathematical model is developed to quantify the effect of the oxygen concentration on the polymerization rate and particle size distribution in an unseeded vinyl chloride batch emulsion polymerization reactor. Particle formation is assumed to proceed by both the homogeneous and micellar nucleation mechanisms. Dynamic species mass balances are derived to follow the evolution of the polymerization rate and particle size distribution (PSD) in the batch reactor. It is shown that, at low initial oxygen concentrations, the polymerization rate increases with the oxygen concentration. On the other hand, the average latex particle size exhibits a U-shaped behavior with respect to the initial oxygen concentration. The experimental observations on the polymerization rate and the average particle size are explained by the combined role of oxygen as an inhibitor and a radical generator through the formation and subsequent decomposition of vinyl polyperoxides. The predictive capabilities of the present model are demonstrated through the successful simulation of experimental data on monomer conversion and PSD obtained from an industrial pilot-plant batch PVC reactor operated with various initial oxygen and initiator concentrations.