The radical addition co-polymerisation of 2-hydroxyethylmethacrylate and butylacrylate is carried out in a continuously operating Buss-Kneader. To calculate temperature profiles over the length of the kneader the heat balance is solved. For the heat transfer coefficient a model based on the penetration theory is used. This model is experimentally verified. The reaction kinetics of the radical addition polymerisation are studied in a differential scanning calorimeter. The polymerisation kinetics are modeled using non-stationary radical concentrations. The calculated temperature profiles over the length of the Buss-Kneader are a good approximation of the experimental data.