Abstract
In the present study an experimental and theoretical investigation on the styrene/2βethylhexyl 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, nonβionic 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/2βethylhexyl 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.