The present study focuses on the development of different cascade control configurations for temperature control of a multiproduct semibatch polymerization reactor. The master controller regulates the reactor temperature by manipulating the mean cooling jacket temperature, whereas the slave controller manipulates the valve opening to control the mean jacket temperature. The configurations explored are based on generic model control (GMC) and proportional integral (PI) control. The effects of different controller tuning parameters are evaluated. The effect of other unmeasured and measured disturbances, i.e., impurity factor, monomer feed flow rate, and presence of measurement noise on control performance, is evaluated for two products A and B. GMC-GMC has shown better controller performance in terms of temperature tracking with minimum root-mean-square output deviation (RMSOD) values as well as minimum normalized root-mean-square input deviation (NRMSID) values from the nominal input value, compared to GMC-PI, PI-GMC, and PI-PI.