Dynamic optimization of semibatch vinyl acetate/acrylic acid suspension copolymerizations

• Published in: Polymer engineering and science Vol. 50; no. 4; pp. 697 - 708
• Main Authors: Machado, Fabricio, Lima, Enrique Luis, Pinto, José Carlos
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 01.04.2010; Wiley; Society of Plastics Engineers, Inc; Blackwell Publishing Ltd
• Subjects: Acrylic acid; Analysis; Applied sciences; Chemical properties; Composition; Controllers; Copolymers; Exact sciences and technology; Industrial polymers. Preparations; Mathematical optimization; Optimization; Polymer industry, paints, wood; Production processes; Simulation; Suspensions (Chemistry); Technology of polymers; Temperature effects; Thermoplastics; Vinyl acetate; Brazil; Structure processing relationship; Kinetic model; Acrylic acid copolymer; Vinyl acetate copolymer; Vinyl ester copolymer; Chemical composition; Radical copolymerization; Experimental study; Modeling; Optimization; Predictive control; Suspension copolymerization
• ISSN: 0032-3888; 1548-2634
• DOI: 10.1002/pen.21572

This work performs the dynamic optimization of semibatch vinyl acetate (VAc)/acrylic acid (AA) suspension copolymerizations. The proposed dynamic optimization strategy is based on a direct search Complex algorithm and is used to control the copolymer composition along the batch. First, a sequential optimization procedure is used to determine the optimum AA concentration and feed rate profiles, required to provide the specified copolymer composition. In the second step, a sequential optimization procedure is coupled with a predictive controller to guarantee that the manipulation of feed flow rates can allow for attainment of the desired copolymer compositions. The optimization strategy is validated through simulation, by assuming that reactions are subject to perturbations of the reaction temperature, initiator, and VAc concentrations. It is shown that the proposed optimization strategy can be used successfully both for design of monomer feed rate profiles and removal of process disturbances during semibatch suspension copolymerizations, to keep the copolymer composition constant throughout the batch. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers