Process for the continuous coagulation of vinyl polymer latices
AssigneeBayer Aktiengesellschaft
InventorsUlrich Jansen, Karl-Heinz Ott, Wolfgang Herrig, Otto Koch, Alfred Pischtschan, Dieter Wittmann
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Abstract
A process for the continuous processing of vinyl polymer latices to produce thermoplastically processible vinyl polymer powder by coagulating a stream of a vinyl polymer latex by the addition of a stream of a coagulant with intensive mixing and shearing in a cascade of vessels at an average residence time per vessel of 10 to 60 minutes and at temperatures from 50 to 120.degree. C., volatile auxiliary substances and residual monomers in the polymer being optionally removed by steam distillation and part of the serum separated from the vinyl polymer being added to the stream of coagulant.
Claims13
A process for the continuous processing of vinyl polymer latices to produce thermoplastically processable vinyl polymer powders, comprising coagulating a stream of vinyl polymer latex at temperatures of 50 to 120 degrees C. by the addition of a stream of an aqueous solution of coagulant with intensive mixing and shearing in a cascade of vessels at an average residence time per vessel of from 10 to 60 minutes, removing volatile auxiliary substances and residual monomers in the polymer by steam distillation, and recycling part of the serum separated from the vinyl polymer to the stream of coagulant.
Dependencies are inferred from the claim text.