Production of self-supporting reticulate sheet

Claim 1

THE PROCESS FOR ISOLATING A CHLOROSULFONATED POLYMER IN THE FORM OF A SELF-SUPPORTING RETICULATE SHEET FROM FLUID SOLUTIONS OF SAID CHLOROSULFONATED POLYMER IN CARBON TETRACHLORIDE, SAID CHLOROSULFONATED POLYMER CONTAINING FROM 20% TO ABOUT 40% CHLORINE AND FROM 0.5% TO ABOUT 4% SULFUR AND BEING DERIVED FROM A POLYMER HAVING A NUMBER AVERAGE MOLECULAR WEIGHT OF AT LEAST 8,000 WHICH IS A MEMBER OF THE GROUP CONSISTING OF POLYETHYLENE AND COPOLYMERS OF ETHYLENE AND A TERMINALLY UNSATURATED OLEFINE OF 3 TO 6 CARBON ATOMS, WHICH PROCESS COMPRISES APPLYING A FILM OF SAID SOLUTION TO A MOVING SMOOTH INERT METAL SURFACE MAINTAINED AT A TEMPERATURE BETWEEN 100* C. AND ABOUT 200* C. AND UNDER AN AMBIENT PRESSURE NOT GREATER THAN ATMOSPHERIC PRESSURE, MAINTAINING THE FILM ON SAID HEATED SURFACE UNTIL THE CARBON TETRACHLORILDE CONTENT OF THE FILM HAS BEEN REDUCED TO NOT MORE THAN ABOUT 3%, AND THEN SEPARATING THE DRIED FILM OF CHLOROSULFONATED POLYMER FROM THE HEATED METAL SURFACE IN THE FORM OF A SELF-SUPPORTING RETICULATE SHEET.