Production of liquid polybutadiene

Claim 1

A METHOD FOR THE PRODUCTION OF LIQUID POLYBUTADIENE FREE FROM SOLID POLYMERS AND OF HIGH TRANSPARENCY AND LOW COLOR WHICH COMPRISES ADDING AN INITIAL CHARGE OF A BUTADIENE POLYMERIZATION FEED OF AT LEAST 98.0 WEIGHT PER CENT 1,3BUTADIENE PURITY AND FREE FROM 1,2-BUTADIENE TO A STABLE DISPERSION OF FINELY DIVIDED ALKALI METAL CATALYST HAVING AN AVERAGE PARTICLE SIZE OF LESS THAN 200 MICRONS IN A BODY OF LIQUID HYDROCARBON SOLVENT IN A CLOSED REACTION VESSEL, SAID INITIAL CHARGE COMPRISING FROM 0.03 TO 0.15 POUND BUTADIENE PER POUND OF SOLVENT AND SAID CATALYST NOT EXCEEDING 2.0 PARTS BY WEIGHT PER 100 PARTS TOTAL BUTADIENE FEED CHARGED, MAINTAINING THE RESULTING REACTION MIXTURE AT 60 TO 110* C., WHILE AGITATING SAME UNTIL POLYMERIZATION IS INITIATED, THEN CHARGING ADDITIONAL BUTADIENE FEED TO THE REACTION MIXTURE WHILE AGITATING SAME AND MAINTAINING SAME AT 60 TO 110* C., SAID ADDITIONAL BUTADIENE BEING ADDED AT A CONSTANT RATE OF FROM 0.03 TO 0.4 POUND PER HOUR PER POUND OF SOLVENT AS RAPIDLY AS POSSIBLE WITHOUT CAUSING THE REACTION MIXTURE TEMPERATURE TO RISE ABOVE 110* C. TO FORM A FINAL POLYMER-SOLVENT REACTION MIXTURE CONTAINING NOT IN EXCESS OF 50 WEIGHT PER CENT OF POLYBUTADIENE, CONTINUING AGITATION OF THE REACTION MIXTURE AFTER ADDITION OF BUTADIENE FEED IS STOPPED UNTIL REMAINING BUTADIENE IS POLYMERIZED, ALLOWING THE REACTION MIXTURE TO SETTLE WITH FORMATION OF AN INSOLUBLE HEAVY LAYER, SEPARATING SAID HEAVY LAYER, CONTACTING THE REMAINING SOLUTION OF POLYBUTADIENE IN SOLVENT WITH AN EXCESS OF CARBON DIOXIDE WHILE UNDER VIGOROUS AGITATION UNTIL THE DARK COLOR OF THE REACTION MIXTURE IS DISCHARGED AND CONTINUING THIS TREATMENT WITH AN EXCESS OF CARBON DIOXIDE FOR AT LEAST 15 MINUTES AFTER SAID DISCHARGE OF COLOR AND THEN REMOVING ANY PRECIPITATE FORMED THEREBY, AND SEPARATING THE SOLVENT FROM THE POLYMER TO PRODUCE A CLEAR LOWCOLOR LIQUID POLYBUTADIENE POLYMER FREE FROM SOLID POLYMER IN SUSPENDED OR DISSOLVED FORM.

Claim 2

A METHOD FOR THE PRODUCTION OF LIQUID POLYBUTADIENE FREE FROM SOLID POLYMERS AND OF HIGH TRANSPARENCY AND LOW COLOR WHICH COMPRISES ADDING AN INITIAL CHARGE OF A BUTADIENE POLYMERIZATION FEED OF AT LEAST 98.0 WEIGHT PER CENT 1,3BUTADIENE PURITY AND FREE FROM 1,2-BUTADIENE TO A STABLE DISPERSION OF FINELY DIVIDED ALKALI METAL CATALYST HAVING AN AVERAGE PARTICLE SIZE OF LESS THAN 200 MICRONS IN A BODY OF LIQUID HYDROCARBON SOLVENT IN A CLOSED REACTION VESSEL, SAID INITIAL CHARGE COMPRISING FROM 0.03 TO 0.15 POUND BUTADIENE PER POUND OF SOLVENT AND SAID CATALYST NOT EXCEEDING 2.0 PARTS BY WEIGHT PER 100 PARTS TOTAL BUTADIENE FEED CHARGED, MAINTAINING THE RESULTING REACTION MIXTURE AT 60 TO 110* C., WHILE AGITATING SAME UNTIL POLYMERIZATION IS INITIATED, THEN CHARGING ADDITIONAL BUTADIENE FEED TO THE REACTION MIXTURE WHILE AGITATING SAME AND MAINTAINING SAME AT 60 TO 110* C., SAID ADDITIONAL BUTADIENE BEING ADDED AT A CONSTANT RATE OF FROM 0.03 TO 0.4 POUND PER HOUR PER POUND OF SOLVENT AS RAPIDLY AS POSSIBLE WITHOUT CAUSING THE REACTION MIXTURE TEMPERATURE TO RISE ABOVE 110* C. TO FORM A FINAL POLYMER-SOLVENT REACTION MIXTURE CONTAINING NOT IN EXCESS OF 50 WEIGHT PER CENT OF POLYBUTADIENE, CONTINUING AGITATION OF THE REACTION MIXTURE AFTER ADDITION OF BUTADIENE FEED IS STOPPED UNTIL REMAINING BUTADIENE IS POLYMERIZED, ALLOWING THE REACTION MIXTURE TO SETTLE WITH FORMATION OF AN INSOLUBLE HEAVY LAYER, SEPARATING SAID HEAVY LAYER, CONTACTING THE REMAINING SOLUTION OF POLYBUTADIENE IN SOLVENT WITH AN EXCESS OF CARBON DIOXIDE WHILE UNDER VIGOROUS AGITATION UNTIL THE DARK COLOR OF THE REACTION MIXTURE IS DISCHARGED AND CONTINUING THIS TREATMENT WITH AN EXCESS OF CARBON DIOXIDE FOR AT LEAST 15 MINUTES AFTER SAID DISCHARGE OF COLOR AND THEN REMOVING ANY PRECIPITATE FORMED THEREBY, AND SEPARATING THE SOLVENT FROM THE POLYMER TO PRODUCE A CLEAR LOWCOLOR LIQUID POLYBUTADIENE POLYMER FREE FROM SOLID POLYMER IN SUSPENDED OR DISSOLVED FORM.