OPTIMIZATION OF ISOTHERMAL BATCHWISE BULK FREE-RADICAL POLYMERIZATIONWITH AND WITHOUT CHAIN TRANSFER AGENT FOR MINIMUM REACTION-TIME

In this work the minimum reaction time was studied for a specific fina l monomer conversion and number-average chain length by adjusting the amount of initial intiator concentration in the presence of a fixed am ount of chain transfer agent at the best isothermal temperature. A new method for the determination of the best initial initiator concentrat ion ([I]0) and isothermal temperature (T) in the presence of chain tra nsfer agent was developed by the application of a simple optimization algorithm, based on the Lagrangian multiplier, to the basic free radic al kinetics. Numerical examples for the polymerization of styrene are presented. It is shown that in the presence of a fixed amount of chain transfer agent the best isothermal policy for minimum time would devi ate from dead-end polymerization. As the concentration of chain transf er agent increases, a stronger deviation from dead-end polymerization is observed. It was found that for a given pair of desired conversion and number-average chain length the usage of a chain transfer agent wo uld result in a longer reaction time. The results give insights into o peration of batchwise bulk free radical polymerization for minimum rea ction time under isothermal conditions.