CONTROL OF SEMICONTINUOUS EMULSION COPOLYMERIZATION REACTORS

The problem of simultaneous control of composition and molecular weigh t of copolymers produced in semicontinuous emulsion polymerization is addressed. A first-principles model of emulsion copolymerization is us ed to produce optimal open-loop policies, which are then experimentall y tested on the system methyl methacrylate/vinyl acetate. In contrast to earlier work in the control of semicontinuous emulsion copolymeriza tion, the control problem addressed has multiple inputs and multiple o utputs, and the experimental application is free of empirical correlat ions and performed on an unseeded system. Optimal open-loop policies a re calculated efficiently by optimizing properties of the instantaneou s polymer being formed. The experimental results confirm the feasibili ty of these techniques. A model-predictive control scheme, in which op timal policies are re-computed on-line to account for disturbances, is proposed. The scheme, which exploits the advantages of the efficient calculation of optimal policies, is tested by simulation showing good performance.