Engineering-Mechanism-Driven Modeling of High-Pressure Polymerization Processes: A Comprehensive Review

Abstract

This review focuses on recent advances in modeling four typical high-pressure free-radical polymerization processes. A four-step engineering-mechanism-driven modeling framework is proposed. The necessary pressure-dependent relations, including physical properties, phase behavior, thermophysical properties, and reaction kinetics, are also discussed. The review indicates that, for tubular LDPE, a one-dimensional model is generally appropriate for describing the axial property and product evolutions. CFD-based corrections can be introduced in locally nonuniform regions. For autoclave LDPE, CFD is required to identify circulation and dead zones. The resulting information can subsequently be reduced to a multicompartment model. For EVA copolymerization, key modeling requirements include copolymerization kinetics, composition drift, and physical property changes. Supercritical CO2 polymerization represents that, for multiphase systems, the model must additionally couple an equation of state, phase equilibrium with mass transfer, and a population balance model. This review can provide a guide for high-pressure polymerization modeling. Model fidelity is selected according to the required observables, with particular attention to kinetic closure, molecular-structure-dependent rheology, and localized decomposition risks.