Process for producing cyanoethylated native cotton fibers by reacting cellulose fibers with acrylonitrile in vapor phase

Claim 1

THE PROCESS OF TREATING NATIVE COTTON FIBERS TO EFFECT BUT A PARTIAL CYANOETHYLATION OF THE CELLULOSE AND RETAIN THE NATURAL PHYSICAL STRUCTURE OF THE FIBERS WHICH COMPRISES IMMERSING SAID COTTON FIBERS IN AN AQUEOUS SOLUTION CONTAINING FROM 0.10 TO 10% OF SODIUM HYDROXIDE TO SORB ON THE CELLULOSE FROM 1.5 TO 22 MILLIGRAMS OF SODIUM HYDROXIDE PER GRAM OF COTTON, REMOVING FROM THE COTTOM SUBSTANTIALLY ALL THE ADHERING LIQUID SOLUTION, AND REACTING THE COTTON WHILE CONTAINING THE SAID SORBED AMOUNT OF SODIUM HYDROXIDE WITH ACRYLONITRILE IN THE VAPOR PHASE AT A TEMPERATURE OF FROM 46*C. TO 85*C AND FOR A PERIOD NOT TO EXCEED 4 HOURS UNTIL THERE IS SUCH AN AMOUNT OF CYANOETHYLATION THAT THE COTTOM CONTAINS FROM 0.50% TO 6.5% OF NITROGEN BASED ON THE WEIGHT OF THE CYANOETHYLATED COTTON, AND RETAINING THE CRYSTALLINE STRUCTURE OF THE COTTON FIBERS SUBSTANTIALLY UNALTERED.