Catalyst system for the emulsion copolymerization of butadiene and styrene

Claim 1

A PROCESS FOR THE COPOLYMERIZATION OF STYRENE AND BUTADIENE IN AN AQUEOUS EMULSION SYSTEM WHICH COMPRISES DISSOLVING FROM 0.01 TO 0.1 PART OF A SODIUM ALKYL BENZENE SULFONATE IN WHICH THE ALKYL GROUPS CONTAIN FROM 10 TO 20 CARBON ATOMS AND FROM 0.05 TO 1.0 PART OF A SODIUM SALT OF A NAPHTHALENE SULFONIC ACID-FORMALDEHYDE CONDENSATE IN FROM 100 TO 150 PARTS OF WATER, DISSOLVING FROM 0.25 TO 0.5 PART OF A CATALYST IN THE STYRENE AND ADDING THERETO FROM 0.5 TO 1.0 PART OF AN ALKYL MERCAPTAN CONTAINING FROM 10 TO 20 CARBON ATOMS IN THE ALKYL GROUP, MIXING THE TWO SOLUTIONS WITH AGITATION AND ADDING THE BUTADIENE THERETO, HEATING THE RESULTANT REACTION MIXTURE TO POLYMERIZATION TEMPERATURE, ADDING TO THE REACTION MIXTURE AN AQUEOUS SOLUTION OF SODIUM FORMALDEHYDE SULFOXYLATE OVER AN EXTENDED PERIOD OF TIME WHILE MAINTAINING THE REACTION TEMPERATURE SUBSTANTIALLY CONSTANT AND THEREAFTER CONTINUING THE REACTION AT SUBSTANTIALLY THE SAME TEMPERATURE UNTIL THE REACTION IS SUBSTANTIALLY COMPLETE, THE SAID CATALYST BEING TAKEN FROM THE GROUP CONSISTING OF COMPOUNDS HAVING THE FORMULA