Mathematical Model of the Heterogeneous Polymerization for the Production of High-Impact Polystyrene

LUCIANI, C. V.; ESTENOZ, D. A.; MEIRA, G. R.

Village Rio das Pedras (RJ), Brasil

Congreso; Enpromer 2005, 4th Mercosur Congress on Process Systems Engineering; 2005

The heterogeneous process for producing high-impact polystyrene is modeled. It predicts: a) global variables such as conversion and grafting efficiency; b) the molecular structure (molecular weight distributions of the free polystyrene, residual polybutadiene, and graft copolymer); and c) the average morphology (number and diameter of rubber particles and occlusions). During the prepolymerization, the crucial phase inversion period occurs, and the rubber morphology is produced. The model contains 3 modules (polymerization, morphology, and thermodynamic). It is the first model in the literature that predicts the system morphology. The model was validated with data from several batch polymerizations (Soto et al., 2004). The presented model can be easily extended to other similar processes (such as the production of ABS and MBS). Also, itcan be combined with a final properties model, and “inverted” for calculating the recipes and operation conditions for producing pre-specified final properties.