Process of producing non-fibrillating acrylonitrile polymer filaments with wet steamtreatment and products produced thereby

Claim 1

A PROCESS FOR PRODUCING SUBSTANTIALLY NON-FIBRILLATING FILAMENTS COMPRISES OF A MATERIAL SELECTED FROM THE GROUP CONSISTING OF ACRYLONITRILE POLYMERS CONTAINING AT LEAST 70 PERCENT OF ACRYLONITRILE AND UP TO 30 PERCENT OF OTHER POLYMERIZABLE MONO-OLEFINIC MONOMERS COPOLYMERIZABLE THEREWITH THE BLENDS OF SAID POLYMERS WITH A POLYMER OF AN ALKENY-SUBSTITUTED N-HETEROCYCLIC COMPOUND, SAID BLENDS CONTAINING FROM 50 TO 80 PERCENT BY WEIGHT OF ACRYLONITRILE, WHICH COMPRISES PLACING SAID FILAMENTS IN A CLOSED CHAMBER WHILE IN AN ORIENTED AND CRYSTALLINE STATE, EVACUATING SAID CHAMBER, INTRODUCING WET STEAM INTO SAID CHAMBER AT A PRESSURE IN THE RANGE OF 30 TO 60 P.S.I.G. AND A TEMPERATURE IN THE RANGE OF 135* TO 155*C. UNTIL THE PRESSURE IN SAID CHAMBER IS IN THE RANGE OF 30 TO 60 P.S.I.G., AND THEREAFTER IMMEDIATELY VENTING THE CHAMBER TO THE ATMOSPHERE, SAID PROCESS BEING REPEATED UNTIL THE FILAMENTS ARE SUBSTANTIALLY NON-FIBRILLATING.