Method for the dosing of additives into polymer melts

The invention relates to a method for the economic and high-quality, in particular homogeneous feeding of additives into polymer melts, such as e.g. antistatics, dyes, nanocomposites, carbon in various modifications, processing aids (zinc stearate, antioxidants) in the form of solutions, dispersions or emulsions. A method for the simultaneous adding to and purifying of a polymer or polymer mixture is involved here, to which is fed in the molten state under pressure first of all an stripping agent, which is finely distributed in the melt and which is then removed again in a degassing chamber under vacuum. By purifying is to be understood in this connection mainly the removal of residual volatile matter. There are stripped out during the above-mentioned vacuum treatment other volatile materials, in particular mono-, di- and trimers, which after the production of the polymer or polymer mixture are present in the latter. The invention is characterized by the fact that additives are mimed with the agent fed to the melt. The improvement compared with the state of the art known to date consists mainly in the fact that the additives supplied are not supplied to the melt separately but together with the stripping agent. No further addition device is therefore required for the adding of the additives.