Copolymers of vinyl acetate and ethylenically unsaturated carboxylic compound havingat least one carboxyl group, compositions prepared from said copolymers and sizing of textile yarns with said compositions

Claim 1

A PRECESS OF PRODUCING COPOLYMERS OF 90 TO 98 MOL PERCENT OF VINYL ACETATE AND 10 TO 2 MOL PERCENT OF AN ETHYLENICALLY UNSATURATED ORGANIC CARBOXYLIC COMPOUND WHICH COPOLYMER IS IN THE FORM OF BEADS AND HAS A MOLECULAR WEIGHT SUCH THAT A MOLAR SOLUTION OF THE COPOLYMER IN 991/2% ETHANOL AND 1/2% BENZENE HAS A VISCOSITY BELOW 18 CENTIPOISES BUT NOT BELOW 7 CENTIPOISES AT 20%C., WHICH COMPRISES ADDING WITH STIRRING IN THE STATED PROPORTIONS VINYL ACETATE MONOMER AND AN ETHYLENICALLY UNSATURATED ORGANIC CARBOXYLIC COMPOUND COPOLYMERIZABLE WITH VINYL ACETATE CONTAINING FROM 3 TO 9 CARBON ATOMS AND HAVING 1 TO 2 CARBOXYL GROUPS, TO AN AQUEOUS SOLUTION WHICH AT LEAST AT THE REFLUX TEMPERATURE AT ATMOSPHERIC PRESSURE OF THE MIXTURE THUS OBTAINED, IN THE PORESENCE IN SAID AQUEOUS SOLUTION OF A PROTECTIVE COLLOID SUSPENDING AGENT SELECTED FROM THE GROUP CONSISTING OF WATERSOLUBLE POLYVINYL ALCOHOL, WATER-SOLUBLE COPOLYMERS OF VINYL ACETATE AND MALEIC ANHYDRIDE, GELATIN, WATER-SOLBLE NATURAL GUMS, GUM TRAGACANTH, WATER-SOLUBLE STARCH, POLYACRYLIC ACID AND POLYMETHACRYLIC ACID AND 1 TO 10% BY WEIGHT, BASED ON THE MONOMERS, OF A PEROXYGEN POLYMERIZATION CATALYST, THE WEIGHT RATIO OT TOTAL MONOMERS TO AQUEOUS SOLUTION BEING FROM ABOUT 1 TO 11 PARTS BY WEIGHT OF MONOMERS TO FROM ABOUT 12 TO 9 PARTS BY WEIGHT OF SAID SOLUTION, SAID MONOMERS BEING ADDED TO SAID AQUEOUS SOLUTION AT THE RATE OF ABOUT 10 TO 17 PARTS BY WEIGHT OF THE MONOMERS PER HOUR FOR EVERY 100 PARTS BY WEIGHT OF SAID SOLUTION, MAINTAINING THE TEMPERATURE OF THE RESULTING MIXTURE AT LEAST AT THE REFLUX TEMPERATURE OF THE MIXTURE AT ATMOSPHERIC PRESSURE DURING THE ADDITION OF THE MONOMERS, THE TOTAL AMOUNT OF SAID SUSPENDING AGENT EMPLOYED IN SAID AQUEOUS SOLUTION DURING THE ADDITION OF THE MONOMER BEING AT LEAST 0.11% BY WEIGHT BUT NOT IN EXCESS OF 1% BY WEIGHT, BASED ON THE MONOMERS, THEREAFTER MAINTAINING THE TEMPERATURE OF THE MIXTURE AT LEAST THE REFLUX TEMPERATURE AT ATMOSPHERIC PRESSURE UNTIL THE REFLUX TEMPERATURE RISES TO AT LEAST 75*C., WHEREBY BY CARRYING OUT THE AFOREDESCRIBED STEPS THE COPOLYMER IS PRODUCED IN THE FORM OF BEADS, COOLING THE MIXTURE, SEPARATING THE COPOLYMER BEADS FORMED DURING THE REACTION FROM THE MIXTURE AND DRYING THE COPOLYMER BEADS.