Analysis of the role of stripping agents in polymer devolatilization

Abstract

A comprehensive model has been developed to analyse the process of polymer melt devolatilization in the presence of a stripping agent, which performs the function of enhancing the molecular diffusion of the desorbing monomer and reducing the interfacial concentration. The problem leads to a coupled set of non-linear partial differential equations with time dependent boundary conditions. This problem has not been solved in the literature so far. The model enables the prediction of the influence of diffusivity ratios, relative volatility, hydrodynamic conditions, etc. on the devolatilizer performance and provides useful guidelines for the selection of a suitable stripping agent. The strategy developed in this work can be also used for related problems of multicomponent desorption in other systems.