Continuous process for the alkaline alcoholysis of polyvinyl esters

Claim 1

A PROCESS FOR THE ALKALINE ALCOHOLYSIS OF A POLYVINYL ESTER OF A SATURATED LOWER ALIPHATIC MONOCARBOXYLIC ACID TO A DESIRED DEGREE GREATER THAN ABOUT 55% OF COMPLETE ALCOHOLYSIS, COMPRISING (1) FORMING A SOLUTION OF THE ESTR AT A CONCENTRATION HAVING A MOBILE VISCOSITY AT THE TEMPERATURE OF REACTION, IN A LIQUID WHICH, COMBINED WITH THE LIQUID PRODUCTS OF ALCOHOLYSIS OF THE POLYVINYL ESTER AND WITH ANY RESIDUAL ALCOHOL FROM THE ALCOHOLYSIS REACTION, IS NOT A SOLVENT FOR THE SOLID PRODUCT OF THE SLCOHOLYSIS, (2) MIXING A CONTINUOUS STREAM OF THE SAID SOLUTION WITH AN CONTINUOUS STREAM OF AN ALCOHOLIC SOLUTION OF AN ALKALINE ALCOHLYSIS CATALYST IN LOWER ALIPHATIC MONOHYDRIC ALCOHOL DURING PASSAGE THROUGH A MIXING ZONE, TO FORM A CONTINUOUS HOMOGENEOUS STREAM OF REACTING SOLUTION CONTAINING AT LEAST SUFFICIENT ALCOHOL TO CARRY OUT THE DESIRED REACTION, (3) CONTINUOUSLY CONVEYING THE SAID SOLUTION, WITHOUT FURTHER MIXING, THROUGH A REACTION ZONE WHILE MAINTAINING IT AT CONSTANT TEMPERATURE UNTIL GELATION AND SYNERESIS HAVE OCCURRED, (4) CONTINUOUSLY REMOVING THE RESULTANT PRODUCTS OF REACTION FROM THE REACTION ZONE AS THE DESIRED DEGREE OF ALCOHOLYSIS IS ACHIEVED, AND (5) NEUTRALIZING THE CATALYST IN THE RESULTANT SOLID PRODUCT BY TREATING THE SAID SOLID PRODUCT WITH AN ACIDIFIED LIQUID WHICH IS AN INERT NON-SOLVENT FOR THE SOLID PRODUCT.