Method of providing a resin reinforced asbestos diaphragm

Claim 1

In a method of preparing an asbestos diaphragm containing a thermoplastic hydrophobic resin which method comprises forming a fibrous chrysotile asbestos mat having the resin therein and thereafter heating the mat to melt said resin, the improvement wherein said resin is capable of being oxidized and degraded when heated above the crystalline melting point thereof in the presence of asbestos, and which method comprises depositing said asbestos diaphragm from an aqueous slurry substantially free of alkali metal chloride and consisting essentially of from about 1 to about 30 weight alkali metal hydroxide and from about 0.1 to about 10 weight percent total asbestos and resin, wherein the resin is from about 0.2 to about 8 weight percent of the total asbestos and resin and wherein the resin is selected from the group consisting of: A. hydrocarbon resins; B. homopolymers having the empirical formula: [CY.sup.I Y.sup.II -- CY.sup.III Y.sup.IV]; and C. copolymers having hydrocarbon and halocarbon moieties wherein the halocarbon moiety is chosen from the group consisting of halocarbons having the empirical formula: [CX.sup.I X.sup.II -- CX.sup.III X.sup.IV ] wherein at least 20 percent of the copolymer is the hydrocarbon moiety; where Y I is halogen chosen from the group consisting of fluorine, chlorine, and bromine, Y II , Y III , and Y IV are chosen from the group consisting of fluorine, chlorine, bromine, and hydrogen, and at least one of said Y II , Y III , and Y IV is hydrogen, and where X I is a halogen chosen from the group consisting of fluorine, chlorine, and bromine, and X II , X III , and X IV are chosen from the group consisting of fluorine, chlorine, bromine, and hydrogen.