The invention relates to a continuous method for producing polyurethanes/polyureas by applying the components of a starting reaction composition individually and/or as a mixture onto an inner region of a hot surface of a rotating body A in the form of a thin film so that the thin film flows across the hot surface of the rotating body A towards an outer region of the hot surface of the rotating body A, the thin film leaving the hot surface as a reaction composition containing polyurethanes/polyurea and the reaction composition being suddenly cooled after leaving the hot surface. The components of the starting reaction composition are a polyisocyanate component and a polyol/polyamine component, the temperature of the hot surface is 70 to 400 DEG C and the sudden cooling of the reaction composition is at least 30 DEG C.