The productivity of batch processes is related to the time required to complete each batch. A self-adjustment optimal method for the vinyl chloride (VC) suspension polymerization is proposed for minimizing polymerization time. By optimizing the concentration of the composite initiators, the polymerization reaction proceeds smoothly so that the cooling capacity of the reactor is fully utilized and the polymerization time is minimized accordingly. In this work, a thermodynamic model is presented to estimate both online reaction advancement and the heat transfer characteristic of the reactor; a kinetic model of composite initiators is referenced to predict the polymerization rate; and a parameter adjustment model is applied to adjust the initiator partition coefficient of the kinetic model for ensuring the prediction performance and compute the maximum limiting polymerization rate for updating the constraints of optimization model. Results show that by choosing the optimal concentration of composite initiators under the constraints of reaction kinetics, maximum limiting polymerization rate, etc., a significant reduction in the total processing time is achieved.