Process for the production of finely divided styrene-butadiene copolymers
Abstract
Abstract A PROCESS FOR THE PRODUCTION OF FINELY DIVIDED STYRENEBUTADIENE COPOLYMERS FROM A CORRESPONDING COARSER COPOLYMER COMPOSITION WHICH COMPRISES DISSOLVING THE COARSER MATERIAL IN A HOMOGENEOUS SOLVENT MIXTURE WHICH CONSISTS OF AT LEAST ONE SOLVENT FOR THE COPOLYMER, AND AT LEAST ONE SOLVENT FOR THE COPOLYMER, THE NON-SOLVENT PART HAVING A HIGHER BOILING POINT THAN THAT OF THE SOLVENT; THEREAFTER REMOVING FROM THE MIXTURE BY VACUUM DISTILLATION THE SOLVENT PORTION TO AN EXTENT AT LEAST SUFFICIENT THAT THE DISSOLVED COPOLYMER IS PRECIPITATED IN THE FORM OF A DISPERSION, AND FINALLY PURIFYING THE MATERIAL THUS PRECIPITATED BY TREATING IT WITH FURTHER NON-SOLVENT WHICH IS HOMOGENEOUSLY MISCIBLE WITH THE RESIDUAL LIQUID.
Inventors
- 👤 Wolfgang Weller
Bibliographic Details
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