Improvement in the carbonation of alkali metal-containing polymers

Claim 1

IN A PROCESS FOR CARBONATING A POLYMER OF A VINYLIDENE-CONTAINING MONOMER SELECTED FROM THE GROUP CONSISTING OF CONJUGATED DIENES AND ARYL-SUBSTITUTED OLEFINS, SAID POLYMER HAVING A MOLECULAR WEIGHT IN THE RANGE OF ABOUT 1000 TO 150000 AND CONTAINING AT LEAST ONE TERMINAL ALKALI METAL ATOM PER MOLECULE, THE IMPROVEMENT WHICH COMPRISES INTRODUCING DRY GASEOUS CARBON DIOXIDE IN AN AMOUNT AT LEAST TWICE THAT REQUIRED FOR STOICHIOMETRIC CARBONATION OF SAID POLYMER AND UNDER PRESSURE INTO A FLOWING POLYMER SOLUTION CONTAINING NOT OVER 20 WEIGHT PERCENT OF SAID POLYMER PASSING THROUGH A MIXING ZONE, MAINTAINING THE PRESSURE WITHIN SAID ZONE BELOW SAID PRESSURE OF THE CARBON DIOXIDE ADDED SO THAT EXPANSION OF SAID CARBON DIOXIDE OCCURS WITHIN SAID ZONE PRODUCING COOLING AND TURBULENT MIXING OF SAID SOLUTION AND CARBON DIOXIDE, THUS MAINTAINING THE TEMPERATURE OF THE REACTION MIXTURE BELOW 60*F. AND WITHDRAWING THE RESULTING MIXTURE FROM SAID ZONE WITHIN ABOUT 5 SECONDS.