Selective membranes from rubber hydrochloride and chlorinated rubber

Claim 1

THE PROCESS OF CONVERTING A MECHANICALLY-STABLE, SELF-SUPPORTING FILM OF AN ORGANIC LINEAR, FUSIBLE, HYDROPHOBIC POLYMERIC SUBSTANCE SELECTED FROM THE GROUP CONSISTING OF RUBBER HYDROCHLORIDE AND CHLORINATED RUBBER, SAID FILM HAVING A HIGH RESISTANCE AND A THICKNESS OF FROM ABOUT 0.02 TO 0.3 MILLIMETER, INTO A HOMOGENEOUS MECHANICALLY-STABLE,SELF-SUPPORTING PER-SELECTIVE MEMBRANE HAVING AN ELECTRICAL RESISTANCE OF LESS THAN 500$ PER CM*2 AS MEASURED IN EQUILIBRIUM WITH A 0.1 N AQUEOUS SODIUM CHLORIDE SOLUTION, WHICH COMPRISES: REACTING SAID FILM WITH A COMPOUND HAVING A DISSOCIATION CONSTANT OF AT LEAST 10*-5 SELECTED FROM THE GROUP CONSISTING OF GUANIDINES, PYRIDINS, DIORGANIC SULFIDES, AND TERTIARY AMINES, CONCENTRATED SULFURIC ACID AND CHLORO SULFONIC ACID, BUY CONTACTING SAID HYDROPHOPBIC FILM WITH SAID COMPOUND WHEREBY SUFFICIENT OF THE CHLORINE ATOMS IN SAID HYDROPHOBIC FILM ARE REPLACED WITH ION EXCHANGE RADICALS SELECTED FROM THE GROUP CONSISTING OF QUATERNARY AMMONIUM, SULFONIC, GUANIDINIUM, PYRIDINIUM AND TERTIARY SULFONIUM GROUPS TO THE EXTENT THAT AT LEAST 0.2 MILLIEQUIVALENTS OF SAID ION EXCHANGE RADICALS ARE PRESENT PER GRAM OF SAID PERM-SELECTIVE MEMBRANE, SAID MEMBRANE HAVING SUBSTANTIALLY THE SAME FORM AND MECHANICAL PROPERTIES AS SAID STARTING FILM.