The modeling of batch and continuous emulsion polymerization reactors. Part I: Model formulation and sensitivity to parameters

Abstract

A detailed model for the prediction of the behavior of batch or continuous emulsion polymerization reactors has been formulated, and an efficient numerical scheme for simulation developed. The model makes use of population balance equations and detailed mechanisms for chemical and physical rate processes. The numerical procedure chosen for its solution is orthogonal collocation on finite elements. In this paper, a few comparisons with experimental data are presented to demonstrate the model validity. Finally, a parametric sensitivity study is carried out to identify the most important kinetic and physical parameters. In the sequel, a comprehensive comparison of model predictions with a wide variety of experimental data will be presented.

Modeling Particle Size Distribution in Heterogeneous Polymerization Systems Using Multimodal Lognormal Function

“…Due to successive nucleations this reaction presents broad and often multimodal PSDs (Rawlings and Ray, 1988). This feature generates consequences for the determination of the search interval of the parameter geometric mean.…”

Modeling particle size distribution in emulsion polymerization reactors

“…Particle size is clearly the most intuitive choice when the objective is to compute the PSD, but there are alternatives, in particular, the birth time. Formulating the problem in terms of the birth time has the advantage of simplifying the PBE, because the divergence with respect to the internal coordinate becomes zero, but also the inconvenience of making it difficult to describe particle coagulation [9]. Therefore, in general, the particle size is the appropriate internal coordinate.…”

“…Accordingly, the accuracy of the results obtained with the PB model will depend on the relative importance of stochastic broadening. For example, stochastic broadening will not be of importance for CSTRs since the PSD is inherently broad [9,32].…”

“…If CLD termination is neglected, an approximate solution can be found by solving a simplified form of the infinite set of density functions mentioned in Section 2.2.1 [4,9]. Assuming that radical entry, desorption and termination are much faster than coagulation, growth and inflow/outflow, we obtain a set of PBEs which is simply a slightly modified version of the Smith-Ewart differential equations [35].…”

Kinetics of vinyl acetate emulsion polymerization in a pulsed tubular reactor: comparison between experimental and simulation results

“…In this second approach good local agitation might be combined with little backmixing, resulting in much higher monomer conversions and particle concentrations than those obtained in single CSTRs (Mayer et al, 1996). In addition, sustained oscillations in those variables due to renucleations that are often observed in CSTRs (Greene et al 1976;Kiparissides et al 1980;Rawlings and Ray, 1988;Hoedemakers, 1990;Paquet and Ray, 1994;Ohmura et al, 1998) or in continuous loop reactors (Araújo et al, 2000) may be minimized or avoided.…”