Abstract: A bilayer or trilayer composite ion exchange membrane suitable for use in a fuel cell. The composite membrane has a high equivalent weight thick layer in order to provide sufficient strength and low equivalent weight surface layers for improved electrical performance in a fuel cell. In use, the composite membrane is provided with electrode surface layers. The composite membrane can be composed of a sulfonic fluoropolymer in both core and surface layers.

Abstract: The invention is a method for forming polymer composite films using removable substrates comprising:(a) forming a first dispersion of a first perfluorinated polymer containing sites convertible to ion exchange groups dispersed in a first dispersant having: a boiling point less than about 110.degree. C.; a density of from about 1.55 to about 2.2; and a solubility parameter of from greater than about 7.1 to about 8.2 hildebrands;(b) depositing the first dispersion onto a first removable substrate;(c) removing the first dispersant from the first dispersion, thereby forming a first film;(d) forming a second dispersion of a second perfluorinated polymer containing sites convertible to ion exchange groups and a second dispersant having: a boiling point less than about 110.degree. C.; a density of from about 1.55 to about 2.2; and a solubility parameter of from greater than about 7.1 to about 8.

Abstract: The invention is a method for forming polymer composite films using a removable substrate comprising:(a) forming a first dispersion of a first perfluorinated polymer containing sites convertible to ion exchange groups dispersed in a first dispersant having: a boiling point less than about 110.degree. C.; a density of from about 1.55 to about 2.2; and a solubility parameter of from greater than about 7.1 to about 8.2 hildebrands;(b) depositing the first dispersion onto a first removable substrate;(c) heating the first dispersion at a temperature sufficient for form and fuse a first polymer film;(d) forming a second dispersion of a second perfluorinated polymer containing sites convertible to ion exchange groups and a second dispersant having: a boiling point less than about 110.degree. C.; a density of from about 1.55 to about 2.2; and a solubility parameter of from greater than about 7.1 to about 8.

Abstract: The invention is a sulfonic fluoropolymer having a fluoropolymer backbone having pendant groups attached thereto and represented by the general formula:ZSO.sub.2 --(CF.sub.2).sub.a --(CFR.sub.f).sub.b --O--where: Z is a halogen, an alkali metal, hydrogen, or OR; R is a branched or linear alkyl radical having from 1 to about 10 carbon atoms or an aryl radical; a is 0-2; b is 0-2; provided a+b is not equal to 0; R.sub.f is selected from the group consisting of --F, --Cl, perfluoroalkyl radicals having from 1 to about 10 carbon atoms and fluorochloroalkyl radicals having from 1 to about 10 carbon atoms, wherein the sulfonic fluoropolymer has an equivalent weight of less than about 725, and a hydration product of less than about 22,000.The invention also includes sulfonic fluoropolymers having a fluoropolymer backbone and having pendant groups attached thereto represented by the general formula:ZSO.sub.2 --(CF.sub.2).sub.a --(CFR.sub.f)b--O--where Z, a, b and R.sub.

Abstract: The invention is a process for producing a modified polytetrafluoroethylene which comprises polymerizing tetrafluoroethylene in an aqueous medium containing a dispersing agent with a polymerization initiator source and then, copolymerizing tetrafluoroethylene one or more fluorinated modifiers having an acid functional group or a functional group which is convertible to the acid group as a copolymerizable modifier in the presence of the resulting polytetrafluoroethylene to a polymerization point past the Kraft point to produce highly porous, fibrous, stratified fluoropolymers having cores made of homopolymer of poly-tetrafluoroethylene coated with sheath layers which are made of a copolymer of polytetrafluoroethylene and one or more modifiers.

Abstract: Novel vinyl ethers are prepared in decarboxylation reactions of novel acid fluoride compounds according to the following reaction: ##STR1## wherein a is 0 or an integer greater than 0;b is 0 or an integer greater than 0;n=1 or an integer greater than 1;R.sub.f and R.sub.f.sup.' are independently selected from the group consisting of F, Cl, perfluoroalkyl or fluorochloroalkyl;X=F, Cl, Br or mixtures thereof when n>1X'=Cl or Br;Y is an acid group or an acid derivative easily convertible to an acid group;Z=F, Cl, Br, OH, NRR' or OA;R and R' are independently selected from the group consisting of hydrogen, an alkyl having one or more than one carbon atoms, and aryl; andA=alkali metal, quaternary nitrogen, or R.These vinyl ethers may be homopolymerized with themselves or copolymerized with other vinyl ethers.

Abstract: Novel vinyl ethers are prepared in decarboxylation reactions of novel acid fluoride compounds according to the following reaction: ##STR1## wherein a is 0 or an integer greater than 0;b is 0 or an integer greater than 0;n=1 or an integer greater than 1;R.sub.f and R.sub.f ' are independently selected from the group consisting of F, Cl, perfluoroalkyl or fluorochloroalkyl;X=F, Cl, Br or mixtures thereof when n>1X'=Cl or Br;D is an acid group or an acid derivative easily convertible to an acid group;Z=F, Cl, Br, OH, NRR' or OA;R and R' are independently selected from the group consisting of hydrogen, an alkyl having one or more than one carbon atoms, and aryl; andA=alkali metal, quaternary nitrogen, or R.These vinyl ethers may be homopolymerized with themselves or copolymerized with other vinyl ethers.

Abstract: The invention is a method for sizing polytetrafluoroethylene fabrics comprising:(a) forming a sizing composition of a perfluorinated polymer containing sites convertible to ion exchange groups and a treating agent having: a boiling point less than about 110.degree. C.; a density of from about 1.55 to about 2.2; and a solubility parameter of from greater than about 7.1 to about 8.2 hildebrands;(b) contacting the sizing composition with the fibers of a polytetrafluoroethylene fabric; and(c) removing the treating agent from the sizing composition.Particularly preferred as a treating agent is a compound represented by the general formula:XCF.sub.2 -CYZX'wherein:X is selected from the group consisting of F, Cl, Br, and I;X' is selected from the group consisting of Cl, Br, and I;Y and Z are independently selected from the group consisting of H, F, Cl, Br, I and R';R' is selected from the group of perflluoroalkyl radicals and chloroperfluoroalkyl radicals having from 1 to 6 carbon atoms.

Abstract: The invention is a method for forming composite polymer films comprising:(a) forming a dispersion of a first perfluorinated polymer containing sites convertible to ion exchange groups and a dispersant having: a boiling point less than about 110.degree. C.; a density of from about 1.55 to about 2.97 grams per cubic centimeter; and a solubility parameter of from greater than about 7.1 to about 8.2 hildebrands;(b) forming a first film of the perfluorinated polymer by depositing the dispersion onto a second polymer film containing ion exchange groups or sites convertible to ion exchange groups; and(c) heating the two films for a time and at a temperature sufficient to fuse the two films to each other.Particularly preferred as a dispersant is a compound represented by the general formula:XCF.sub.2 --CYZX'wherein:X is selected from the group consisting of F, Cl.

Abstract: The invention is a method for sizing polyterafluoroethylene fibers, yarns, or threads comprising:(a) contacting polytetrafluoroethylene fibers, yarns, or threads with a sizing composition of a perfluorinated polymer containing sites convertible to ion exchange groups and a treating agent having:a boiling point less than about 110.degree. C.;a density of from about 1.55 to about 2.97 grams per cubic centimeter; anda solubility parameter of from greater than about 7.1 to about 8.2 hildebrands; and(b) removing the treating agent from the sizing composition, thereby depositing the perfluorinated polymer onto the surface of the polytetrafluoroethylene.Particularly preferred as a treating agent is a compound represented by the general formula:XCF.sub.

Abstract: The invention is a process for making a high surface area, self-supporting catalyst suitable for use as an acid catalyst comprising:(a) at least partially polymerizing a perfluorinated monomer containing ion exchange groups convertible to an acid or salt form in a medium containing a gas-forming ingredient(s) which is present during polymerization and serves a polymerization enhancement purpose during polymerization; wherein the said gas-forming ingredient(s) is a material that will convert into a gaseous state and expand when heated; and(b) heating the polymer to a temperature sufficient to soften the polymer and sufficient to convert at least a portion of the gas-forming ingredient(s) into a gaseous state while the polymer is still in contact with at least a portion of the gas-forming ingredient(s), thereby converting the gas-forming ingredient(s) into a gas which expands the polymer and causes the formation of open and closed pores within the polymer.

Abstract: The invention is a method for coating polytetrafluoroethylene fabrics, fibers, yarns, or threads comprising:(a) contacting polytetrafluoroethylene fabrics, fibers, yarns, or threads with a sizing composition of a perfluorinated polymer containing sites convertible to ion exchange groups and a treating agent having:a boiling point less than about 110.degree. C.;a density of from about 1.55 to about 2.97 grams per cubic centimeter; anda solubility parameter of from greater than about 7.1 to about 8.2 hildebrands;(b) removing the treating agent from the sizing composiiton, thereby depositing the perfluorinated polymer onto the surface of the polytetrafluoroethylene; and(c) hydrolyzing the perfluorinated polymer to make it water wettable.Particularly preferred at a treating agent is a compound represented by the general formula:XCF.sub.

Abstract: Compounds represented by the general formulas ##STR1## are prepared by reacting halofluoropropylene oxides with fluorinated acid fluorides and ketones.These compounds may be decarboxylated to form useful monomers, ##STR2## wherein a=to 3;b=to 3;c=0 or 1;provided a+b+c.noteq.0;n=zero or an integer greater than zero;R.sub.f =F, perfluoroalkyl or fluorochloroalkyl;X=F, Cl, Br or mixtures thereof when n>1;X'=Cl or Br;Y=Cl, Br, F or I;Z=F, OH, NRR' or OA;R and R' are independently selected from the group consisting of hydrogen, an alkyl having one or more than one carbon atom and an aryl;A=alkali metal, quaternary ammonium, R or an aryl.These monomers may then be polymerized into polymers having useful properties.

Abstract: The invention is a method for forming a supported membrane film comprising:(a) at least partially coating a polytetrafluoroethylene fabric with a sizing composition;(b) contacting the coated polytetrafluoroethylene fabric with a membrane film having sites convertible to ion exchange groups; and(c) heating the polytetrafluoroethylene fabric and the membrane film while maintaining the fabric and the film in contact.

Abstract: The invention is a method for sizing polytetrafluoroethylene fabrics comprising:(a) forming a sizing composition of a perfluorinated polymer containing sites convertible to ion exchange groups and a treating agent having: a boiling point less than about 110.degree. C.; a density of from about 1.55 to about 2.2; and a solubility parameter of from greater than about 7.1 to about 8.2 hildebrands;(b) contacting the sizing composition with the fibers of a polytetrafluoroethylene fabric; and(c) removing the treating agent from the sizing composition.Particularly preferred as a treating agent is a compound represented by the general formula:XCF.sub.2 --CYZX'wherein:X is selected from the group consisting of F, Cl, Br, and I;X' is selected from the group consisting of Cl, Br, and I;Y and Z are independently selected from the group consisting of H, F, Cl, Br, I and R';R' is selected from the group of perfluoroalkyl radicals and chloroperfluoroalkyl radicals having from 1 to 6 carbon atoms.

Abstract: Novel vinyl ethers are prepared in decarboxylation reactions of novel acid fluoride compounds according to the following reaction: ##STR1## wherein a is 0 or an integer greater than 0;b is 0 or an integer greater than 0;n=1 or an integer greater than 1;R.sub.f and R.sub.f ' are independently selected from the group consisting of F, Cl, perfluoroalkyl or fluorochloroalkyl;X=F, Cl, Br or mixtures thereof when n>1X'=Cl or Br;Y is an acid group or an acid derivative easily convertible to an acid group;Z=F, Cl, Br, OH, NRR' or OA;R and R' are independently selected from the group consisting of hydrogen, an alkyl having one or more than one carbon atoms, and aryl; andA=alkali metal, quaternary nitrogen, or R.These vinyl ethers may be homopolymerized with themselves or copolymerized with other vinyl ethers.

Abstract: Fluorovinyl compounds having the formulaTLCF.dbd.CF.sub.2are prepared by reacting compounds having the formula ##STR1## for a time and at a temperature sufficient to form the vinyl compound: whereX=Cl, Br or I;Z=F, Cl, Br, OH, NRR', OA, or SA;R and R' are independently selected from the group consisting of hydrogen, an alkyl having one or more than one carbon atom, and aryl;A=Alkali metal, alkali earth metal, quaternary nitrogen, or R;L=oxygen or sulfur; andT=an alkyl or aryl radical which does not interfere with the reaction.

Abstract: Compounds represented by the general formulas ##STR1## are prepared by reacting halofluoropropylene oxides with fluorinated acid fluorides and ketones.

Abstract: An improved polymer for use as an ion exchange membrane in an electrolytic cell wherein the polymer has pendant chains containing sulfonic acid ion exchange groups and has an equivalent weight of between about 800 and about 1500. The polymers have a hydration product of less than about 22,000.The electrolytic cell and its method of operation are described when these polymers are used as ion exchange membranes.

Abstract: An electrolytic cell and a process for electrolysis using the cell are provided. The electrolytic cell is separated into an anode chamber and a cathode chamber by a fluorinated polymer membrane; wherein the membrane comprises:(a) at least 60 mole percent [CFX--CF.sub.2 ] where X=F or Cl;(b) an ion exchange equivalent weight of at least 600;(c) pendant sulfonyl ion exchange groups; and(d) pendant substantially fluorinated carbon groups which have no ion exchange functionality.These cells are particularly useful for the electrolysis of aqueous, alkali metal halides.