Digital Strategies to Improve Product Quality and Production Efficiency of Fluorinated Polymers: 1. Development of Kinetic Model and Experimental Verification for Fluorinated Ethylene Propylene Copolymerization

Digitalization of industrial polymerization processes represents an effective and efficient approach for product-grade upgrading and for production efficiency improvement. A mechanistic model based on the first principles of elementary reactions and mass balances provides a powerful tool in the practice of process digitalization. In this work, we developed a comprehensive kinetic model for the batch process of bulk copolymerization of tetrafluoroethylene with hexafluoropropylene. A series of experimental runs were carried out under various conditions. The fluorinated ethylene propylene copolymer samples were collected, with the monomer conversions, copolymer compositions, and polymer molecular weights, as well as the melting and crystallization properties, fully analyzed. The model was then correlated with the data for estimation of the model parameters. The reactivity ratios were found to be r 1 = 65.5 and r 2 = 2.6 × 10–3. With a whole set of estimated parameters, the model was used to simulate results under different polymerization conditions close to industrial production processes, which were further verified with additional experimental data. The agreement between simulated and experimental results was good. The experimentally verified model provides a powerful tool for industrial process optimization aiming at improvement of product quality and production efficiency.