On-Line Optimizing Control of Bulk Free Radical Polymerization Reactors under Temporary Loss of Temperature Regulation: Experimental Study on a 1-L Batch Reactor

On-line optimizing control of bulk free radical polymerization of methyl methacrylate is carried out in a 1-L virtually instrumented stainless steel batch reactor. The polymerization is carried out under an optimal temperature history computed off-line. The experimental histories of the temperature of the reaction mass, and of the agitator current required for stirring the contents of the reactor at constant speed, are used to update (retune) the kinetic parameters describing the gel and glass effects periodically, so that the model can be used to infer the state (monomer conversion and the weight-average molecular weight) of the system more accurately. On-line optimizing control, involving retuning the kinetic model, followed by reoptimizing and implementing the temperature history, is carried out both in the absence of any disturbance and in the presence of a simulated heater failure. Improved results are obtained.