Process for making acrylonitrile polymer solution

Claim 1

A PROCESS FOR THE PRODUCTION OF A SOLUTION OF A POLYMER OF ACRYLONITRILE CONTAINING AT LEAST 80% BY WEIGHT OF ACRYLONITRILE IN THE POLYMER, WHICH SOLUTION IS CAPABLE OF BEING EXTRUDED DIRECTLY INTO A COAGULATING BATH WITHOUT PREVIOUS PRECIPITATION, COMPRISING DISSOLVING A SUBSTANCE CONSISTING ESSENTIALLY OF A POLYMERIZABLE MATERIAL SELECTED FROM THE GROUP CONSISTING OF MONOMERIC ACRYLONITRILE AND MIXTURES OF ACRYLONITRILE WITH STYRENE, METHYL ACRYLATE, VINYL ACETATE AND VINYL PYRIDINE, SAID MIXTURES CONTAINING AT LEAST 80% ACRYLONITRILE, IN AN AQUEOUS SOLUTION CONTAINING ABOUT 35% BY WEIGHT THIOCYANATE ION AS THE SOLE INORGANIC ANIONIC COMPONENT, ADDING A CATALYST SELECTED FROM THE GROUP CONSISTING OF AZO-BIS ISOBUTYRONITRILE, AZO-BIS-ISOBUTYRIC ACID ESTERS, DIAZOAMINOBENZENE, PHENYL-DIAZOAMINE-N-DIETHYL ETHYLENE DIAMINE, DIAZOAMINOTETRAZOLE, P,P''-DINITRO-DIPHENYLAZOSULFONE, DIAZOANHYDRIDE, POTASSIUM AZO-DISULFONATE DIAZONIUM DIPHENYLAMINE, P-AMINO-BENZENE SULFINIC ACID AND MIXTURES THEREOF, TO THE SOLUTION AS THE SOLE POLYMERIZATION CATALYST, AND HEATING THE SOLUTION TO AT LEAST 50*C. TO POLYMERIZE SAID MATERIAL IN SAID SOLUTION.