Part I of this series described the modeling and characterization of a reaction calorimeter designed for studying polymerizations under real process conditions. In this part, a calibration heater is used as a model reaction and it is shown how accurately the reaction rate can be determined with the calorimeter. Polymerization conditions strongly affect the sensitivity of the calorimetric measurements, After careful characterization of the calorimeter, polymerization reactions can be accurately followed, even when the reaction is started below the target temperature. The polymerization can be characterized during a small conversion interval at the outset of the polymerization. The special features of polymerizations are demonstrated and the typical process parameters such as viscosity, heat transfer properties and heat generation are presented for four types of polymerizations.