Process for hydrolyzing ethylenealkyl acrylate copolymers with aqueous ammonia

Claim 1

A PROCESS COMPRISING INTRODUCING AN ETHYLENE-ALKYL ACRYLATE COPOLYMER HAVING A MOLECULAR WEIGHT OF LESS THAN ABOUT 10,000 INTO A HYDROLYSIS ZONE, SAID ETHYLENE-ALKYL ACRYLATE COPOLYMER HAVING A HYDROCABON CHAIN STRUCTURE WHEREIN ABOUT 10 TO 25 PERCENT OF THE CARBON ATOMS HAVING ATTACHED THERETO SUBSTITUENT GROUPS, INTRODUCING AQUEOUS AMMONIA INTO SAID HYDROLYSIS ZONE AND THEREIN CONTACTING SAID ETHYLENE-ALKYL ACRYLATE COPOLYMER, MAINTAINING THE TEMPERATURE OF SAID HYDROLYSIS ZONE ABOVE 170*C., AND WITHDRAWING FROM SAID HYDROLYSIS ZONE AN ETHYLENEALKYL ACRYLATE WATER-SOLUBLE POLYMER HAVING A HYDROCARBON CHAIN STRUCTURE, ABOUT 10 PERCENT TO 25 PERCENT OF THE CARBON ATOMS OF SAID CHAIN HAVING ATTACHED THERETO SUBSTITUENT GROUPS, OF WHICH LESS THAN 65 PERCENT ARE CARBALKOXY, FROM 20 TO ABOUT 97 PERCENT ARE CARBAMYL AND FROM ABOUT 2.6 TO 80 PERCENT ARE SELECTED FROM THE GROUP CONSISTING OF CARBOXY AND AMMONIUM CARBOXYLATE SUBSTITUENTS, SAID POLYMER BEING WATER-SOLUBLE AND HAVING A MOLECULAR WEIGHT LESS THAN ABOUT 10,000 AND FORMING A TRANSPARENT STABLE SOLUTION IN WATER AT A PH ABOVE ABOUT 6, SAID POLYMER FORMING A SUBSTANTIALLY WATER-INSENSITIVE FILM.