Process for the production of pourable, pulverulent rubbers

Claim 1

A PROCESS FOR PREPARING DISCRETE, FINELY DIVIDED, TACKFREE, POURABLE, POWDERY FILLER-FREE ELASTOMER PARTICLES FROM AN AQUEOUS EMULSION OF AN ELASTOMERIC POLYMER HAVING CRYSTALLINE OR THERMOPLASTIC BLOCK SEQUENCES AND SELECTED FROM THE GROUP CONSISTING OF EPM- OR EPDM BLOCK SEQUENCE COPOLYMERS HAVING AN ETHYLENE CONTENT OF 65-80% AND A RAMAN CRYSTALLINITY OF 0.3-1.5 R; COPOLYMERS OF BUTADIENE WITH A STYRENE OR A-METHYLSTYRENE VINYL AROMATIC MONOMER HAVING A MOLAR RATIO OF BUTADIENE TO THE VINYL AROMATIC MONOMER OF 1 :1-1:6, 20-100% OF THE VINYL AROMATIC MONOMER BEING IN BLOCK SEQUENCE FORM AND CONSTIUTING AT LEAST ABOUT 20 MOL OF THE COPOLYMER STRUCTURE: AND A STEROHOMOPOLYMERS OF BUTADIENE CONTAINING 10-30% TRANS-1,4 DOUBLE BONDS IN A STEREO BLOCK SEQUENCE CONFIGURATION, SAID AQUEUOS EMULSION CONSISTING ESSENTIALLY OF (I) A SOLUTION CONTAINING 4-25% BY WEIGHT OF SAID ELASTOMER DISSOLVED IN A VOLATILE, INERT ORGANIC SOLVEN HAVING A BOILING POINT BELOW 100*C., (II) AN ELASTOMER EMULSIFYING AMOUNT OF ABOUT 0.05-2% OF A SURFACTANT AMINE DERIVATIVE AND (III) WATER, THE WEIGHT RATIO OF THE AQUEOUS PHASE TO THE ORGANIC SOLVENT PHASE OF SAID EMULSION BEING FROM ABOUT 0.25 TO 2.5:1, WHICH PROCESS COMPRISES: GRADUALY INTRODUCING SAID ADMIXTURE INTO AN AQUEOUS ALKALI SILICATE SOLUTION CONTAINING 0.5-20 MOLES OF SIO2 PER MOLE OF SAID AMINE SURFACTANT WHILE MAINTAINING SAID SILICATE SOLUTION AT A PH WHICH DESTABILIZES THE SURFACTANT; SIMULTANEOUSLY EVAPORATING SAID VOLATILE ORGANIC SOLVENT TO FORM SAID ELASTOMER PARTICLES; AND DRYING SAID PARTICLES AT A TEMPERATURE BELOW THE SOFTENING POINT THEREOF.