Semi-Batch Emulsion Copolymerization: A General Model for a Copolymer Formed from n Monomer Units

摘要

A detailed, general monodisperse mathematical model for seeded semi-continuous emulsion copolymerisation (SCEP) with n comonomers is presented. The presented model describes the SCEP process in detail using radical, monomer and particle balances in water and particle phase and employing a phase equilibrium as the connection. This approach, though in parts known from other modelling approaches, is new in incorporating the latest research on dynamic radical balances, particle nucleation, the gel effect and the avarage number of radicals per particle. It is, however, limited to conditions without a droplet phase. Every conceivable SCEP process can thus be described once the physical data has been provided and the model can easily be extended by a batch-reactor heat balance. Results have been calculated for the pairs and triples (Vinyl Acetate-Butyl Acrylate), (Vinyl Acetate-Butyl Acrylate-Methyl Methacrylate), (Butyl Acrylate-Methyl Methacrylate), (Methyl Methacrylate-Styrene). The model works also for the homopolymerisation for Methyl Methacrylate, Styrene and Vinyl Acetate. The results for Vinyl Acetate and Butyl Acrylate show reasonable agreement with published experimental data.