JPS5837187A - Membrane, electrochemical cell and electrolysis - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention]

The present invention relates to ion exchange membranes that operate at low voltages and high current densities, thus having low power consumption and good tear resistance, and their use. Fluorinated ion exchange polymers containing carginic acid and/or sulfonic acid functional groups or salts thereof are known in the art. One major use of such polymers is as a membrane component used to isolate the anode and cathode compartments of chlor-alkali electrolyzers. Such membranes may be in the form of reinforced or unreinforced films or laminate structures. For use in chlor-alkali baths, it is desirable that membranes operate at low voltages and high current densities and therefore with low power consumption, giving high quality products at low prices in view of today's increasingly increasing energy costs. . It is further desirable that the membrane be tough and resistant to damage during its manufacture and use in such cypresses. Since existing films of ion exchange polymers have a low tear strength, it has been found necessary to strengthen them by manufacturing them with reinforcing materials, such as reinforcing fibers. However, the use of reinforcement in the membrane is not entirely beneficial. One drawback is that the use of reinforcing materials such as textile fabrics makes the membranes thicker, resulting in membranes that can only be used at high voltages because the increased thickness increases electrical resistance. Melt. Efforts to lower resistance by using thinner films when manufacturing reinforced membranes have resulted in the use of fabric windows (
It is often unsuccessful because some of the membranes (windows) rupture, resulting in leaky membranes. (By "window" we mean an open area between adjacent threads of a textile fabric). Leaky membranes are undesirable in that they allow anolyte and catholyte to flow into opposite cell chambers, reducing current efficiency and impure the product produced. Furthermore, at the intersections of the threads of the reinforcing fiber cloth, the layer of electrically bonded material becomes thick, forming a high resistance region. (The term "intersection" here means the point where the weft and warp threads overlap). A second drawback, which also leads to use at high voltages, is induced by the "shadow effect" of the reinforced membrane. The shortest path for ions through the membrane is from one surface to the other. A straight, perpendicular path to the surface. Reinforced membranes are uniformly made of materials that are not permeable to ions. There are areas of the membrane where ions cannot pass vertically and in a straight line through the membrane, and where ions pass through the reinforcement member. The part of the membrane where a circuitous path around the membrane must be taken is called the "shadow zone." When a "shadow zone" is introduced into the membrane through the use of reinforcement, the The effective ion transport capacity will be reduced and the operating voltage of the membrane will therefore increase. The part of the shadow area is referred to as the "blind area". The main object of the present invention is low voltage and high current efficiency, thus operating with low power consumption, yet having good tear resistance. It is an object of the present invention to provide an ion exchange membrane.Another object is to provide a thin and strong ion exchange membrane.Other objects will become clear from the description below. According to the invention, a reinforced membrane with a high aspect ratio as defined below, a polymer layer with carboxylic acid functional groups downstream of the reinforced membrane, and a conduit (cha- nnelB
), an ion exchange membrane is provided. More particularly, at least two layers of fluorinated polymers having -COOM and/or -803M functional groups, in which M is H, Na, K or NH4, adjacent layers adhere to each other; and a web of support material embedded therein, the ion exchange membrane being impermeable to hydraulic flow of a liquid, the first said layer having a -C00M functional group and a -80,M functional group. there is at least a second said layer having

[1. The total thickness of at least two core layers of the fluorinated polymer is
-COOM and/or -SO used in the production of iron films,
W functional group [where R is lower alkyl and/or W
is F or CI] in the range of 50 to 250 microns, and the web of support material has a thickness of about 25 to 125 microns and at least 50% The cough intensifier defines a window area between them [2, and the conduit in the membrane runs from the window area to the blind area, where the intensifier defines the window area between them. An ion exchange membrane is provided, characterized in that it is located near a layer of 1. Further, according to the present invention, there are provided a precursor membrane for producing an ion exchange membrane, an electrochemical cell containing the ion exchange membrane as a component, and an electrolysis method using the ion exchange membrane. Membranes of the invention typically contain 1000R and/or -SO
! It is prepared from a web of two or more layers of a fluorinated polymer having a W functionality, where R is lower alkyl and W is F or CI, and a support material. The first layer of polymer with which this invention relates is typically a cardanic acid polymer having fluorinated hydrocarbon chains (all pendant) containing functional groups or functional groups. This pendant side chain may be, for example, [wherein 2 is F or CF, t is 1 to 12, and V is 1000R or -CH, where R is lower alkyl Normally, the functional group in the side chain of the polymer will be present at the terminal 10→c F-)-V group. Examples of fluorinated polymers for this food are:
British Patent No. 1,145,445, US Patent No. 4.11
No. 6,888 and US Pat. No. 3,506,635. More particularly, the polymers are prepared from monomers that are fluorinated or fluorine-substituted vinyl compounds. Polymers are usually made from at least two monomers. The monomer of at least 1 m is a fluorinated vinyl compound, such as vinyl fluoride, hexafluoropropylene, vinylidene fluoride, trifluoroethylene, chlorotrifluoroethylene, perfluoro C alkyl vinyl ether), tetrafluoroethylene, and mixtures thereof. It is. For copolymers used in brine electrolysis, the precursor vinyl monomer will desirably be hydrogen-free. Furthermore, at least 1'ja of the monomers has a group that can be hydrolyzed to a carboxylic acid group,
For example, Cal is a -fluorinated monomer containing an alkoxy or nitrile group in the side chain as described above. The term "fluorinated polymer" here refers to a polymer that loses its R group through hydrolysis and becomes an ion-exchanged polymer, with the number of F atoms increasing to F atoms and H
It means a polymer in which the number of atoms is at least 90%. The monomers are preferably hydrogen-free except for the R group of -COOR, especially when the polymer is used for brine electrolysis, and are most preferably hydrogen-free for maximum stability in harsh environments. will be free of both hydrogen and chlorine, i.e. will be monofluorinated; the R group must be fluorinated since it is lost during hydrolysis when the functional group is converted to an ion exchange group. l! There isn't. One suitable class of cal-xyl-containing monomers is illustratively of the formula %, where R is lower alkyl, YFiF or OF, and S is 0.1 or 2 ]. These monomers in which S is 1 are
This is preferred because its production and separation in good yields are easier to achieve than when S is 0 or 2. Compound CF, =CFOCF, CFOCFICOOCH. C.F. are particularly useful monomers. Such monomers can be obtained, for example, from a compound having the formula % [wherein S and Y have the same meanings as above], (1) the terminal vinyl group is saturated with chlorine to obtain OF, (:
By converting it to 1-CFe1- group, it is
C2) Oxidize with nitrogen dioxide to 10 CF, OF! 80. (3) esterification with an alcohol such as methanol to generate -ocp, cooeps groups; and dechlorination with zinc dust to form terminal Cp,=C]"- However, instead of this sequence Q) and (31), (at-OCF, -CF, 80.
Sulfinic acid, -0CF, CF, by treatment of the F group with sulfite or hydrazine, 80. H. or its reduction to an alkali metal or alkaline earth metal salt; (b) oxidation of sulfinic acid or its salt with oxygen or chromic acid to produce 100F, e00H group or its metal salt; and (c) known -0CF, C00C by the method of
Esterification to H, can also be used. This sequence is described in more detail in US Pat. No. 4,267,364 in connection with the preparation of copolymers of such monomers. Other suitable types of carboxy-containing monomers have the formula % [where ■ is -COOkL or -CN, R is lower alkyl, Y is F or CF, and Z is F or CF, and S is 0.1 or 2]. The most preferred monomers, because they are easily polymerized and converted to the ionic form, are -COU)t, where R is lower, generally C1-CI alkyl. Monomers in which S is 1 are also preferred because their production and separation in good yields is easier to achieve than when S is O or Fi2. The preparation of these monomers and copolymers thereof in which 1 is -000R, where R is lower alkyl, is described in U.S. Pat. No. 4,131,740. a compound whose method of manufacture is indicated therein;
CF, , = CPOCF, CFOCF, CF, COOC
H3, Ohi CF. CF, ,,=CFO(CF, CFO) t OF,
CF, C00C)l. C.F. are sometimes useful monomers. (2) A method for producing a 10N monomer is described in U.S. Pat. No. 3,854,326. Furthermore, other suitable types of carboxyl-containing polymers include 10 (
CF,) C00CH, [where V is 2-2o], e.g. cFt=cp-o(CF't), eoOcH3 and OF
,=CFOCF,CF(CF,10(CFt),C00
CH. , g1. Methods for producing such monomers and copolymers thereof are described in Japanese Patent Publication No. 52-38486 and Japanese Patent Publication No. 52-28586, and British Patent Nos. 1 and 14.
No. 5,445. The other 11% of the carboxyl-containing polymer contains repeating units [wherein q is 3-15, r is 1-10, S is 0, 1, or 2, and t is 1-12] , X together are 4 fluorines or 3 fluorines and 1 chlorine, YFi, F or CF, Z FiF or OF, and RFi lower alkyl. Represented by a polymer. A preferred group of copolymers is tetrafluoroethylene and the formula % wherein n is 0.1 or 2, m is 1.2.3 or 4, Y is F or CF, and and R is CH, , C, H, or C, H. Such copolymers to which the present invention relates can be prepared using known techniques,
For example, U.S. Pat. No. 3,528,954, U.S. Pat.
．． No. 131.740 and African Patent No. 78/22
It can be manufactured by No. 25. The sulfonyl polymers to which this invention relates are typically polymers having a fluorinated hydrocarbon chain further attached with a functional group or pendant side chains bearing a functional group. The pendant side chain is, for example, -CF, -CF-80tW f [wherein R4 is FXCl or a C8-C1° perfluoroalkyl group, and W is F or CI, preferably F]. It can contain. Usually the functional groups in the side chains of the polymer will be present in the terminal groups -0-CF, -CF-80,F. Examples of fluorinated polymers of this type are disclosed in U.S. Pat. Nos. 8,284,875, 3,560,568 and 3,718,627. More particularly, the polymers can be prepared from fluorinated monomers or fluorine-substituted vinyl compounds. The polymer is made from at least two monomers, at least one from each of the following two groups. At least one monomer is a fluorinated vinyl compound such as vinyl hafluoride, hexafluoropropylene, hnylidene fluoride, trifluoroethylene, chlorotrifluoroethylene, perfluoro(alkyl vinyl ether), tetrafluoroethylene, and the like. It is a mixture of For copolymers used in brine electrolysis, the precursor vinyl monomer desirably does not contain hydrogen. The second group is the precursor group -CF, -CF-80! It is a sulfonyl-containing monomer containing F. A further example can be represented by the general formula % where T#i is a difunctional fluorinated group of 1 to 8 carbon atoms and kFio or 1. The substituent atomic group in T is fluorine,
Contains chlorine or hydrogen, although hydrogen is generally excluded when the copolymer is used for ion exchange in chloralkali baths. The most preferred polymers have no hydrogen and chlorine bonded to carbon, ie they are perfluorinated for maximum stability in harsh environments. The T Go stone of the above formula may be branched or unbranched, that is, it may be linear,
It may have one or more ether bonds. The vinyl group in the group of comonomers containing sulfonyl fluoride is attached to the T group through an ether linkage, ie the comonomer has the formula cr, =cF-o-T-CF, 80. F
It is preferable that the Examples of comonomers containing sulfonyl fluoride such as CF, =CFOCF, CFit, 80tF. CF, = UFOCF, CFOCF, CF, 80. F. C.F. CF, CF. CF,=CFCF,CF,80. F, and CF, = CF
OCF, CPOCF, CF, 80. F ■ OF. ■Direct CF. It is. The most preferred sulfonyl fluoride-containing comonomer ha,barfluor(3,6-thioxal 4-j thyl-7-
octensulfonyl fluoride), CF, =CFOCF
, CFOCF, OF, So, F0F. It is. Sulfonyl-containing monomers are described in U.S. Pat.
No. 5, No. 3,041,317, No. 71 & 627, and No. 3,560,568. Preferred class 111 such polymers include repeating units [wherein h is from 3 to 15, j is from 1 to 10, p FiOll or 2, and l- taken together with 4 fluorine or 3 fluorine and 1 chlorine, Ytj:P' or CF, and Rf is F', C
I or 01-C1'. is a barfluoroalkyl group]. The most preferred comonomer is tetrafluoroethylene and barfluor (3,6-thioxal-4-methyl-7-octensulfonyl fluoride), the latter in an amount of 20 to 65%;
Preferably it is a copolymer containing 25 to 50% by weight. Such comonomers used in the present invention are compatible with the general polymerization methods developed for the homo- and copolymerization of fluorinated ethylene, particularly for tetrafluoroethylene, which are described in the literature. It can be manufactured by the method described below. A non-aqueous process for making copolymers is described in U.S. Pat.
No. 041,317, i.e. a mixture of the main monomers, e.g. In the presence of the compound and at a temperature θ~200°C and a pressure 101~2
Including methods of polymerizing at X10' Pascals (1 to 200 atmospheres) or higher. The non-aqueous polymerization can be carried out in the presence of a paper-forming solvent, if desired. Additional fluorinated solvents are inert liquid perfluorinated hydrocarbons such as perfluoromethylcyclohexane, perfluorodimethylcyclobutane,
Perfluorooctane, perfluorobenzene, etc., and inert liquid alkali fluorocarbons, such as 1.
1.2-1lichloro-1,2,2-trifluoroethane, etc. An aqueous method for making copolymers involves contacting the monomers with an aqueous medium containing a radical initiator, as described in U.S. Pat.
393,967 to obtain a slurry of polymer particles in a non-aqueous wet or particulate form, or a monomeric fl radical initiator and a technically inert dispersant. For example, US Pat. No. 2,559,752 and! 2,593,58
The process involves obtaining an aqueous colloidal dispersion of polymer particles and hardening the dispersion as disclosed in No. 3. Co-electropolymers containing different types of functional groups can also be used as one of the component films in making the membranes of the invention. For example, produced from monomers selected from the group of non-functional monomers mentioned above, monomers from the group of carboxylic acid monomers mentioned above and also monomers from the group of sulfonyl monomers mentioned above. tprpolymers can be made and used as one of the film components in making membranes. Additionally, a film that is a mixture of two or more polymers can be used as one of the component films of the membrane. For example, a mixture of a melt-processable form of the polymer having sulfonyl groups and a melt-processable form of the polymer having carboxyl groups may be used as one of the component films of the membrane of the present invention.
It can be manufactured and conveniently used as one. Furthermore, it is also possible to use the product term film as one of the component films in producing the membrane. For example, a film having a melt-processable copolymer layer having sulfonyl groups and a melt-processable copolymer layer having carboxyl groups is used in the manufacture of the present invention as one of the component films. Can be used. When applied to a film or membrane for isolating the anode and anode chamber of an electrolytic cell, e.g. a chlor-alkali cell, the sulfonate polymers treated herein are converted to an ionizable form and then 0.5 to 2mm child/9, preferred 1. <
is at least 0.6 mm Y/I and more preferably 0
．． It should have a total ion exchange capacity of 8 to 1.4 IJ equivalents/g. If the ion exchange capacity is less than 0.5 milliequivalents*711, the electrical resistance becomes too high and the ion exchange capacity is 2 milliequivalents/I.
If it exceeds this, the electrolyte will swell excessively, resulting in poor mechanical properties. The relative amounts of components constituting 1 coalescence are determined by the ion conversion barrier in the electrolyzer and 1. When used as a polymer, the polymer should be adjusted or selected to have an equivalent weight of no more than about 2000. The equivalent weight at which the resistance of the film or membrane is too high for practical use in an electrolytic cell varies somewhat with the thickness of the film or pus. For thin films and membranes, equivalent weights up to about 2000 can be tolerated. Normally, the equivalent weight is small <4600
, preferably should be at least 900. The monolithic film having the sulfonyl groups in ion-exchanged form will preferably have a weight in the range of 900-1500. However, for many purposes and for films of normal thickness, values of no greater than about 1400 are preferred. In the carboxylate polymers addressed herein, when used to isolate the chambers of chloralkali baths, the requirements regarding ion exchange power are different from those of the sulfonate polymers. The cal-xylate polymer has a resistance of at least 0.05° to provide an acceptably low resistance of 411°.
6 millimeters/9, preferably at least 0.7 millimeters/9, and most preferably at least 0.8 millimeters/9.
It has to shoulder the ion exchange capacity of 9. Such values are particularly acceptable for films with a thickness in the thinner range of 10 to 100 microns, and for films in the middle and thicker parts of this range the ion exchange capacity is At least 0.7 mm/! ? , good? j, 〈should be 0.8 meq/g.・Ion exchange capacity is 2
It should be less than or equal to millivol/9, preferably less than or equal to 1.5 milliequivalents/I, and more preferably less than or equal to 1.3 milliequivalents/g. In terms of equivalent weight, cal-xylate polymers most preferably have an equivalent weight in the range <Fi 770 to 1250. The membranes of the present invention are made from component polymer films ranging in thickness from about 13 microns (0.5 mils) to about 150 microns (6 mils) 1 in thickness. Since the membrane is generally made from two or three such polymer films,
The total thickness of the polymeric film used in making the resulting membrane is generally about 50 to 250 microns (2 to 10 mils).
, preferably 12< is 75 to 200 microns (3 to 8 mil),
Most preferably about 75-150 microns (3-6 mils)
It will be. The conventional method of defining the structural composition of membranes in this art is to determine the polymer composition, equivalent weight and thickness of the polymeric film in melt-processed form, and the hydrolyzed ionic father from which the membrane is made. Chivalry is carried out in both cases. The reason for this is that () the thickness of the reinforced membrane is not uniform, i.e. it is thicker at the intersections of the reinforcing fabrics and thinner elsewhere, and the measurements taken with a caliber or micrometer do not show the highest thickness; This is because measuring the cross section using a microscope and photography is troublesome and time consuming. Additionally, in the case of hydrolyzed ionic membranes, the measured thickness depends on whether the membrane is dry or swollen with water or electrolyte, or even if some of the amount of polymer is electrolyzed. It varies depending on the ionic strength and ionic strength of the liquid. Since membrane function is partly a function of the amount of polymer,
The simplest way to define the structural composition is the nine methods described immediately above. The web of support material is suitably a woven or non-woven paper. In either case, the web is a reinforcement and a temporary (sa)
Consists of both critical members. For woven fabrics, regular basket weave and leno
) A weave like a weave is appropriate. Both reinforcing yarns and temporary yarns may be monofilament or multi-strand. Reinforced Jjfl perhalocarbon polymer yarn. "Perhalocarbon polymer" as used here is
Ether is used to refer to polymers having monocarbon chains with or without oxygen bonds and substituted entirely with fluorine or with fluorine and chlorine atoms. Preferred perhalocarbon polymers are perfluorocarbon polymers due to their greater chemical inertness. Typically, such polymers are homopolymers made from tetrafluoroethylene and hytetrafluoroethylene and hexafluoropropylene and/or where the alkyl group has from 1 to 1 carbon atoms.
Contains a copolymer of 10 perfluor(alkyl vinyl ether), e.g. perfluor(propyl vinyl ether). An example of the most suitable reinforcing material is polytetrafluoroethylene. Reinforcing threads made from chlortrifluoroethylene polymers are also useful. In order to provide adequate strength to the fabric prior to lamination and to the membrane after lamination, the reinforcing yarn should be of 50-6002 denier, preferably 200-400 denier (denier is 9000 m of yarn). number of grams per hit). However, such denier threads with typical round cross-sections require a suitable thickness to ensure that the reinforcement is up to twice the thickness of the thread and thus leak free. It is necessary to use film layers of fluorinated polymers, and the total effective thickness necessitates operation at high voltages, resulting in unsatisfactory membranes. According to the invention, fiber fabrics are used in which the reinforcement has a particular denier but is non-circular, ie with a cross-sectional shape having an aspect ratio of 2 to 20, preferably 5 to 10. By aspect ratio is meant the ratio of the width of the stiffener to its thickness. Typically suitable cross-sectional shapes include rectangular, oval and oval. The rectangular members may be in the form of thin, narrow strips cut from the film, or may be extruded as such. Note that in this case, the corners can be rounded. Oval, oval, and other shapes may be extruded or made by rolling the fibers or yarns flat. It is also possible to obtain the required aspect ratio by pressing the woven fabric flat with a roll. A rectangular cross section as described above is preferred. Support material wet f#i25
~125 microns (1-5 mil), preferably t150~
Having a thickness in the range of 75 microns (2-3 mils), the reinforcement is 12-63 microns (0.5-25 mils)
It should preferably have a thickness of 25 to 38 microns (1 to 1.5 mils). The fibrous fabric should have a thread calanthra in the range of 1.6 to 16 reinforcing threads/3 (4 to 40 threads/inch) in each of the warp and weft threads. A yarn count within the range of 6 to 8 reinforcing yarns/C is preferred. The temporary member of the textile fabric is any number of threads of any suitable material, natural or synthetic. Suitable materials include cotton, linen, silk, rayon, nylon 6-6, polyester terephthalate, and polyacrylonitrile. Cellulosic materials are preferred. The main requirement for fugitive fibers is that they can be removed without adversely affecting the polymer matrix. Under these conditions, the chemical make-up of the temporary fibers is not critical. Similarly, the method of removing temporary fibers is not rigorous in that its removal does not interfere with the ion exchange capacity of the final polymer in the cation-permeable separator. By way of example, temporary fiber removal of cellulosic materials, such as resin, can be carried out using hypochlorous acid. Fugitive fibers are fibers that can be removed without adversely affecting either the intermediate polymer, which is a precursor to the polymer with ion exchange sites, or the polymer with ion exchange sites. The fugitive fibers are removed from the polymer until t leaving voids without interfering with the ion exchange capacity of the final polymer. The temporary fiber removal method must not affect the supporting fibers used to strengthen the isolation wall. The temporary member, such as a thin ribbon cut from rayon thread or reapposed cellulose film, suitably has a diameter of about 40 to 100
It's Denil's. They can have an aspect ratio in the range 1 to 20, i.e., have a rectangular, oval or oval cross-section, or, if sufficiently low denier, an aspect ratio of 1, i.e. circular in cross-section. can be of. As in the case of reinforcing threads, the temporary threads should have a thickness of 12 to 63 microns, preferably 25 to 38 microns. In each of the warp and weft threads, the ratio of temporary threads to reinforcing threads of the textile cloth should be within the range of 10:1 to 1:1. The preferred ratio of temporary fibers to reinforcing fibers is 2:1 to 6:
1, most preferably 2:1 to 4:1. Furthermore, it is preferred that for each reinforcing fiber there is an even number of temporary fibers. Fabrics with an odd number of fugitive fibers for each reinforcing fiber can also be used, but they are not the preferred class m. The reason for this preference can be seen by observing what happens in the case of textile fabrics of normal weave with one temporary fiber for each reinforcing fiber: Remove fibers 1-running time;
The remaining reinforcing fibers are not in the form of a textile; one set of fibers is simply located on top of another, and while such is acceptable in the present invention, it is not preferred. Of course, in such cases it is also possible to use special weaves that remain woven after removing the temporary fibers. To avoid the need to make such special weaves,
Fabrics having an even number of fugitive fibers for each reinforcing fiber are preferred. Reinforcing fiber fabrics can be made with existing high aspect ratio yarns twisted or untwisted. When twisting, the number of twists is small so that a high aspect ratio is maintained. The reinforcing fabric should be such that after subsequent removal of the temporary threads, the fabric has an open area of at least 50%, preferably at least 65%. Here is the "opening"
(e) The area of the window relative to the area of the fiber cloth is expressed as a percentage. In the case of nonwoven paper, thin open sheets of suitable component fibers can be used. The reinforcement is perhalocarbon polymer fiber. As used herein with respect to nonwoven paper, the term "fiber" refers to cho-pped fibers cut from filaments.
fibers) as well as fiprid and fib-IJ
/'4 Includes. The perfluorocarne is in the same sense as described above for the perhalocarne polymer system, and is also preferably a perfluorocarbon. These fibers have a denyl of 5 to 1 o and a length of 3 to 20-1, preferably 5 to 10 days. The fugitive member is a fiber of cellulosic or other material as described above with respect to fugitive yarn. Characteristics of paper fibers can be defined by Hahalp's standard tests that define the "freeness J," such as the "Canadian Standard Degree of Freedom" defined in TAPPI Standard T227m-58. Suitable degrees of freedom values for paper temporary members are within the range of 300-750@j Canadian standard. A preferred embodiment is a kraft fiber. Paper sepa-halocardan fibers 10-90% by weight and fugitive fibers 90-10% by weight, preferred. It consists of 25-75% by weight perhalo cardan fibers and 75-25% fugitive fibers. Paper Fi25-125II/m”, preferably 50g/
As in the case of woven fabrics, the thickness of the paper should be from 25 to 125 microns (1 to 5
mil), preferably 50-75 microns (2-3 mil)
within the range of at least 50% after temporary fiber removal
The tube should preferably have an opening of at least 65%. Membranes can be made from the component layers of the film and the web of support material with the aid of heat and pressure. In order to melt bond the polymeric films used together to form a single membrane structure with the support material, first, if more than two films are used, adjacent film sheets are fused together. In order to achieve this, a temperature of typically 200 to 300°C is required. However, the required temperature may be above or below this range, depending on the polymer used. A suitable temperature option in that case is that if the temperature is too low, the films will fail to adhere properly to the reinforcement and to each other and/or large voids will form between the films adjacent to the reinforcement. Therefore, if the temperature is too high,
This will be evident due to excessive polymer fluidization resulting in leakage and non-uniform polymer thickness. The pressure is about 2
It can be used from pressures as low as x10' Pascals to pressures in excess of 107 Pascals. Appropriate types of equipment for patch operations include:
It is typically a hydraulic press using pressures in the range of 2 x 10" to 10 Pascals. Equipment suitable for continuous production of membranes and used in the examples unless otherwise specified includes an internal heater and an internal vacuum source. The hollow roll includes a series of circumferential slots on its surface and an internal vacuum source draws the component material towards the hollow roll. A curved stationary plate with a radiant heater comprises a The upper surface of the hollow roll and approximately 6 cm (-inch)
facing the distance. During the lamination operation, a porous release paper is used as a support material in contact with the hollow roll to prevent adhesion of the component material to the roll optical surface, and a vacuum source draws the component material toward the hollow roll. Supply and removal means are provided for component materials and products. In the supply means, an antler roll having a smaller diameter than the hollow roll is placed against the release paper and the component materials. The supply and removal means are positioned such that the component material passes around the circumference of the medium in a ridge of approximately s/, of its circumference. A second antler is placed against the release paper to separate it from the other materials. Removal means are provided for the release paper and the product film. When used for ion exchange purposes and in electrolytic cells, such as chloralkali cells for the electrolysis of brine, the 7 membrane should have all functional groups converted to ionizable functional groups. Normal and good 1 [. Alternatively, these are sulfonic acid and cardanic acid groups, or their alkali metal salts. Such conversion is usually and conveniently carried out by hydrolysis with acids or bases so that the functional groups described above for melt-processable polymers are converted to the free acid or alkali metal salt thereof, respectively. achieved by. Such hydrolysis can be carried out using mineral acids or aqueous solutions of alkali metal hydroxides. Hydrolysis with a base is preferred because it proceeds quickly and completely. The use of hot solutions, such as solutions near the boiling point, is preferred for fast hydrolysis. The time required for hydrolysis increases with the thickness of the structure. It is advantageous to include a water-miscible organic compound, such as dimethyl sulfoxide, in the hydrolysis column. Removal of the fugitive fibers from the membrane can variously occur before, during, or after converting the original membrane in melt-processable form to an ion exchange membrane. It can be carried out during the cough conversion if the temporary member is destroyed by the hydrolysis column used for the conversion. An example of this is the caustic hydrolysis of nylon polymers. For example, in the case of rayon fugitives, removal may be effected prior to the conversion by treatment with aqueous hypochlorous acid (IJ). At this time, the fugitive fibers are removed and a membrane is produced in which the functional groups of the polymer layer are of the 1000R and -5OtW type. Hydrolysis may be carried out first. In this case, the functional group is converted to -COOH and -8o, H or a salt thereof,
Membranes of ion-exchange type are produced that still contain fugitive fibers;
The fugitive fibers are then removed, in the case of rayon or other cellulose or polyester members, by the action of the hypochlorous acid formed in the cypress during electrolysis, if the membrane is used in a chlor-alkali bath. can be done. When the temporary member is removed from the membrane, a conduit remains in the membrane at the location originally occupied by the temporary member. These conduits are generally sha-dowed from the window area.
That is, it extends in the blind region 1, while the reinforcing member is located close to the functional polymer having carboxyl functionality. The conduits have a nominal diameter of 1 to 50 microns. This nominal diameter is the same as that of the fugitive fiber, whose removal results in the creation of a conduit. The actual diameter of the conduit will vary due to shrinkage or collapse of the membrane as it is dehydrated, and due to swelling and swelling of the membrane itself. Typically, the conduits remaining after removal of the fugitive threads of the fabric are in the range of 10 to 50 microns in diameter, and in the range of 1 to 20 microns in diameter upon removal of the fugitive from the paper. The membranes of the invention are characterized in that the support material does not penetrate through the first layer of a fluorinated polymer having carboxyl functionality, but is at least primarily composed of a fluorinated polymer having carboxyl functionality. A fluorinated polymer having one and preferably sulfonyl functionality in the other layer is produced, originally present in the second layer, which is the surface layer of the membrane. As a result, the conduits are present at least primarily in layers other than the first layer of the monopolymer and preferably also in the second layer of the polymer having sulfonyl functionality. The ion-exchange membrane conduits created by the removal of temporary members do not penetrate the membrane from one surface to the opposite surface, so that the membrane does not exceed the water pressure of the liquid at the typical low pressures that occur in chlor-alkali baths. Impermeable to flow. (A diaphragm that is porous does not cause a change in the composition of the hydraulic flow of liquid passing through it, whereas an ion-exchange membrane allows ion It is an easy method to determine the presence or absence of a conduit through the membrane by a leak test using gas or liquid. However, the conduit may or may not be open or closed, ie, penetrating from the second layer of fluorinated polymer to the surface of the membrane. In each case, the conduit extends from the window area of the membrane to the blind area. It is preferable that the conduit in the second layer opens to the surface of the membrane. The reason is that such membranes work at lower voltages than membranes with occluded channels. When the ion exchange membrane is used for the electrolysis of saline water, the layer with carxyl functionality is directed towards the anolyte and the second layer, preferably with sulfonic acid functionality, is directed towards the anolyte (saline water). , the conduit is open if the reinforcing member serves to transport the brine to the blind region within the membrane near the layer with carboxyl functionality, or similarly if occluded. This serves to transport the liquid penetrating into the surface portion of the second layer up to the blind area. If the ratio of temporary yarns to reinforcing yarns in the fabric is 1:1, the conduit after removal of the temporary yarns runs from the window area to the blind area adjacent to one half of the yarn segment. By "yarn segment" we mean the length of reinforcing yarn that extends from the intersection of one yarn to the intersection of an adjacent yarn. If the ratio of temporary yarn to reinforcing yarn is 2=1, the conduit after removal of the temporary yarn runs from the window area to the blind area adjacent to all yarn segments. As the ratio of temporary threads to reinforcing threads increases PAK, the number of conduits to the blind area that are subsequently created increases further. Therefore, the ratio of temporary yarn to reinforcing yarn is at least 2. :1 fiber cloth is suitable. For paper support materials, the paper portion remaining in the membrane after removal of the temporary fibers is between 2.5 and 112J9,1 m", preferably 4
51/m'' or less. The channels formed when the fugitive fibers of the paper support material are removed appear to be interconnected. -coo as one surface layer
a first layer of fluorinated polymer with only n functional groups, a second layer of fluorinated polymer with only −80,F functional groups as another surface layer, and a support embedded in the second layer It consists of a web of body material. The first layer is about 25-75
and the second layer has a thickness in the range of about 75 microns.
It has a thickness in the range of ~150 microns. After hydrolysis to the ion exchange form and removal of the temporary members of the support material, the resulting ion exchange membrane is a suitable membrane for chloralkali baths. More preferably, this latter membrane conduit is an open conduit as described above. When such membranes have two layers of fluorinated polymers, they may contain three or more layers of polymer, such as a polymer layer with -000R, -SO, From the polymer layer with W, the web of support material and the other layer of polymer with -SO,W groups, the web of support material is completely or completely removed, as seen in some of the examples below. At least almost completely -S
It is processed in the above order so as to be embedded in a matrix having O and W groups. In the claims, the thickness of the component layers is the nominal thickness, i.e. the thickness of the layers used before combining to make the membrane, and the total thickness of the -1 membrane is its thickness after the membrane is manufactured. Regarding. The main use of the ion exchange membrane of the present invention is in electrochemical baths (EL).
ctrochemical cell). Such a cell comprises an anode, an anode chamber, a cathode, a cathode chamber and a membrane located to separate the two iron masses. One example is a chloralkali bath. In this case, the membrane should have functional groups in salt form; in such a bath,
The layer of membrane in which the cal has xyl functionality will be placed towards the cathode chamber. Electrochemical cells, particularly chlor-alkali cells, will normally be constructed such that the air gap or spacing between the anode and cathode is narrow, ie no wider than about 3 meters. The cell may also be operated with the membrane in contact with either the anode or the Fi cathode, as can be achieved by suitable water pressure in one cell chamber or by the use of an open mesh or grid separator that contacts the membrane and electrode. and electrolysis is often advantageous. Furthermore, zero-gap configuration
In the arrangement referred to as gura-tionl, it is often advantageous to have the membrane in contact with both the anode and the cathode. Such an arrangement offers the advantage of minimizing the resistance introduced by the anolyte and catholyte, thus allowing operation at low voltages. With or without such an arrangement, either or both monopoles may have a suitable catalytically active surface layer of any type known in the art for reducing overpotentials at the electrodes. The membranes described herein can have electrocatalyst compositions on either surface or both surfaces and be used as materials to make composite membranes/electrodes. Such electrocatalysts are of the type known in the art, such as U.S. Pat.
, No. 697 and published UK patent application OB2.009,7
88A. Suitable cathodic electrocatalysts include the white metals, Raney nickel and hirthenium black. Suitable anode electrocatalysts include white metals and complex ruthenium and iridium oxides. The membranes described herein may also be provided with a gas- and liquid-permeable porous non-electrode layer thereon, such as by optimal surface roughening or smoothing, or preferably with a gas- and liquid-permeable porous non-electrode layer thereon to enhance the gas emission properties. Either or both surfaces can be modified by providing a. Such non-electrode layers can be in the form of thin hydrophilic coatings or spacers and are usually comprised of inert, electrically inactive or non-electrocatalytic materials. Such a non-electrode layer is 10-99
%, preferably from 30 to 70%, and from 0.01 to
average pore size of 2000 microns, preferably 0.1 to 1000 microns, and generally 0.1 to 600 microns,
Preferably it should have a thickness in the range of 1 to 300 microns. The non-electrode layer usually consists of an inorganic component and a binder; the inorganic component is described in published British patent application GB 2,064,5.
86A, impregnated with tin oxide, titanium oxide, zirconium oxide, or Fe,
0° or an iron oxide such as Fe s 04. Other information regarding non-electrode layers on ion exchange membranes can be found in published European patent application no.
It is described in No. 112487. The binder component in the non-electrode layer and in the electrocatalyst composition layer is, for example, polytetrafluoroethylene, at least the surface of which is modified with functional groups such as 100OH or -80,H by treatment with ionizing radiation in air or by a modifier. Introducing (
fluorocarbon polymers, carboxylate or sulfonate functional groups which have been made hydrophilic by treatment with reagents such as sodium in liquid ammonia (as described in published UK patent application QB 060,703A) or by treatment with reagents such as sodium in liquid ammonia. Can be polytetrafluoroethylene particles modified with functionalized fluorocar &/polymers or copolymers or fluorinated copolymers with acid-type functional groups on the surface (QB 2,064 .5・86A). The composite structure having a non-electrode layer and/or an electrocatalyst composition layer thereon can be prepared using various methods known in the art. For example, the preparation of a decal (deca 1 ) which is then pressed onto the membrane surface, the application of a slurry (e.g. a dispersion or drying, screen or gravure printing of pasty compositions, hot pressing of powders distributed on the membrane surface, and GB 064586A
Other methods are included, such as those described in . Such structures can be made by applying the above-mentioned layers in melt processable form onto the membrane and in ion exchange form by certain methods; the resulting structure When the polymer component is in a melt-processable form, it can be hydrolyzed to an ion-exchange type by a known method. The non-electrode layer and the electrocatalyst composition layer can be used on the membrane in a variety of combinations. For example, the surface of the membrane can be modified with a non-electrode layer, and an electrocatalytic composition layer can be placed on the latter. It is also possible to provide on top of the membrane a layer containing both an electrocatalyst and a conductive non-electrode material, such as a metal powder with a higher overpotential than the electrocatalyst, in combination with a binder in a single layer. A preferred type of membrane is one having a cathodic electrocatalyst composition on one surface and a non-electrode layer on its opposite back surface. Membranes having one or more electrocatalytic layers, or one or more non-electrode layers, or a combination thereof on their surface, can be used in narrow-gap or zero-gap metering electrochemical cells as described above. can do. The copolymers used in the layers described herein, both in melt-processable precursor form and in hydrolyzed ion-exchange form, have molecular weights high enough to produce at least moderately strong films. Should have. To further illustrate the innovative aspects of the invention, the following examples are presented. The abbreviations in the examples are as follows. P T F-E means polytetrafluoroethylene; TF'E/EVE means a copolymer of tetrafluoroethylene and methyl perfluoro(4,7-thioxer-5-methyl-8-nonenoate) EW means equivalent weight; EXAMPLE A reinforced cation exchange membrane was prepared by thermally bonding the following layers together under heat and pressure: A, 25 of T'FE/EVE with an equivalent type 1i1 (EW) of 1080; Cathode surface layer consisting of microns (1 mil). '1rFB/PSEP with equivalent weight of 8.1100
76 micron (3 mil) layer of VE. Support fabric containing both C0 reinforcing and temporary yarns. - The thread is torn PTFE with a thickness of 19 microns (<0.75 mil) and a width of 508 microns (20 mil).
It is a 200 denier monofilament consisting of a film, which has been burned 3.5 times per ink and flattened to a thickness of 3.
8 microns (1,5 mil 4) and width 254 microns (1
0 mil) with a cross section of 7.87 yarn/
warp and weft counts of .era (20 threads/inch). This yarn had an aspect ratio of 6.7. The temporary yarn was a 50 denier rayon yarn with a warp and weft count of 15.75 yarns 7 cm (40 yarns/inch). The total thickness of the fabric was 76 microns (3 mils). lJ, 'II'FE/PS with equivalent weight of 1100
Anode surface layer consisting of a 25 micron (1 mil) film of EPVE copolymer. First, layers A and B were crimped together without heat, being careful to exclude air trapped between the layers. The four layers were then passed through a thermal laminator with layer D supported on a web of porous release paper. In the heating zone, vacuum is applied from the underside of the porous release paper and the TFE/P
The air trapped between the two layers of 8 EPVE was drawn through the thin molten bottom layer (D layer), thereby completely encapsulating the reinforcing fabric. The temperature of the heating zone was adjusted such that the temperature of the polymer exiting the heating zone was 230-235° C. as measured by an infrared measuring device. After lamination, the composite membrane was treated with 30% dimethyl sulfoxide and 1
Hydrolysis was carried out at 90° C. for 20 min in an aqueous bath containing 1% KOH. The film was then rinsed and mounted in a wet state in a small chloralkali bath with an active area of 45 aeI'' between a dimensionally stable anode and a metal cathode drawn from soft iron. It was operated at 90°C with electric current. The salt content at the anolyte outlet was maintained at 200 #/1. The S degree of caustic produced by adding water to the anolyte is 32±1
%. After 8 days, the cypress was running at 3.55 volts and 97% current efficiency. This ability did not change after 36 days of operation. Pouch Example 2 The rAJ pigeon has an equivalent weight of 1080 1' F E/
Example 1 was repeated except with a 50 micron (2 mil) layer of EVE. After 8 days of testing in a small chloralkali bath, the membrane was 3.65
It was operating at 97% volt and current efficiency. This ability remained unchanged at 1 even after 37 days of operation. Example 3 TFE/P8EP with rJ layer having equivalent weight of 1100
Example 1 was repeated except with a layer of VEO 101 mil 1 loa (4 mil). After 8 days of testing in the chloralkali tank, the membrane was 3.65
& rut and was operating at a current efficiency of 97%. This ability remained unchanged even after 37 days of operation. Example 4 T F E/E with rAJ- having an equivalent weight number of 1080
Consisting of a 50 micron (2 mil) layer of VE and "B"
TFE/P8EPVE whose layer has an equivalent weight of 1100
Example 1 except that it consisted of a layer of O101 mil (4 mil)
repeated. The membrane was tested in a small chloralkali bath under the same conditions as in Example 1 except that the temperature of the hinoki was 80°C. After 6 days of operation, the membrane was running at 3.70 volts and a current efficiency of 95.2%. Ta. Comparative Example A This teaching example shows that when a reinforcing fiber cloth containing monofilaments with a low aspect ratio and no temporary threads is used,
The effect on the potential of the electrolytic cell is shown. The membrane was fabricated by thermally bonding the following layers: A, 'I'FB with equivalent type @ (EW ) of 1080
/EVEO25mi1. Cxn (1 mil) cathode surface layer. 8.110(1) Equivalent weight t-W 'l'FE/PS
EPVE (D 101 Miku CM/(4 mil) layer. Fabric with only reinforcing yarns without any C0 temporary yarns, the reinforcing yarns are 96 coul% of tetrafluoroethylene and Hiberfluor (propyl vinyl ether). It consisted of monofilaments extruded at >200 denier with a circular cross section of 127 cry (5 mils) in diameter of 4% by weight copolymer (see U.S. Pat. No. 4,029,868, Comparative Example C). It had an aspect ratio of 1't-.The fabric had a warp count of 13
．． 8 threads/- (34 threads/inch) and weft count 6.7
It was a leno weave of thread/cIn (17 threads/inch). The fabric was passed between heated rolls to a total thickness of 239 microns (9.4 mils). The yarn flattened slightly at the intersection point and the aspect ratio of the yarn increased from 1 to 1.13''! 1), T)'E/PSEP with an equivalent weight of 1100
Anode surface layer consisting of a 51 micron (2 mil) film of VE copolymer. The above components were thermally bonded, hydrolyzed and their performance evaluated as in Example 1. After 9 days in the small chloralkali bath, the odors were operating at 3.80 volts and current efficiency (average of 3 seed tests) of 95.2%. Attempts to make thinner membranes with the same reinforcing fabric using less than 25 microns (1 mil) of either layer A, B, or D have shown that (1) the membrane leaks if attempted at high processing temperatures; , or (21 For attempts at low processing temperatures, fabric C
It was unsuccessful because a large void was formed between the films B and 0 next to the threads of the film. Both conditions are
This made the membrane unsuitable for long-term use in chlor-alkali baths. Comparative Example B This comparative example shows the effect on voltage of cypress when using a reinforcing fabric containing monofilaments with high aspect ratio and no fugitive threads. Layer C consists of a monofilament of P T F E film torn to 300 denier, which is used as a thread to a thickness of 5
0.4 micron (2 mil) and width 305 micron (12
Micron) and warp and weft count 15.75
The construction was the same as Example B except for the reinforcing fabric with thread/3 (40 threads/inch). Note that the aspect ratio of the yarns in layer C was 6/1, and no temporary yarns were included. After 6 days in a small J chloralkali bath, the membrane was running at 4.0 volts and a current efficiency of 94.5%. This example illustrates the method of the present invention by using a reinforcing fabric consisting of monofilaments and fugitive yarns having high aspect ratios. The layers of the membrane were as follows: A, 51 microns of j050EW TFE/EVE (2
mil) layer. H, 1100EW's 'l'FE/PSEPVE's 101
Micron (4 mil) layer. A fabric containing both C0 reinforcing and temporary yarns. The reinforcing yarn consisted of 200 denier P'I'FE multifilament yarn flattened to 305 microns (12 mils) in fiber and 56 microns (2.2 mils) thick. This aspect ratio was 5.5. The thread count in both warp and weft directions is 5.9 threads/m (15
thread/inch). The temporary yarn consisted of 50 denier rayon yarn with warp and weft curls of 23.6 (60 threads/inch). The total thickness of the fabric was 112 microns (4.4 mils). D, Tti”E/PSE with an equivalent weight of 11000
Anode surface layer consisting of 25 microns (1 mil) of PVE copolymer. The structural components were thermally bonded, hydrolyzed 17 and evaluated in a small chloralkali bath as in Example 1, except that the bath temperature was 80°C. After 9 days of operation, current efficiency is 96.7
% and potential were 3.68°. After 53 days, the value was 95.9% and 3.62 volts. Comparative Example C This comparative example illustrates the effect on cell voltage of using a reinforcing fabric having high aspect ratio multifilament yarns but without interwoven fugitive fibers. The composition of the laminate was the same as Example 5 except that the reinforcing fiber fabric was as follows: Layer C was a fabric containing only reinforcing yarns without fugitive yarns. This is 200
Denyl P T F E multifilament warp 20 threads/
cm (51 threads/enI) and 400 denyl weft 10.
It was a len weave consisting of 2 yarns, 151 (26 yarns/inch). The width of the threads is 508 microns (20 mils) and the thickness is 63.5 microns (2.5 mils) at the intersection of the threads.
The fiber cloth was treated with a hot roll so that The aspect ratio was 8.0. The total thickness of the cloth is 127 microns (5,0
Mill). This structural component was thermally assembled and hydrolyzed. Roughly half of the rage area leaked. This indicated that the thickness of the polymer layer was a limit. The leak-free range was evaluated in a 74% chloralkali bath as in Example 1 except that the temperature of the cypress was 80°C. After 7 days in Hinoki,
The membrane was operated at a current efficiency of 96.5% and 3.99°. This was 310 mm higher than Example 5 with temporary threads. Example 6 This collection of examples illustrates the method of the present invention using a nonwoven reinforcing material containing a mixture of fluorocarbon polymer fibers and fugitive fibers. A, TFE/Ev with equivalent weight (EWl) of 1080
- Extreme surface layer consisting of 51 microns (2 mils) of E. TF'E/P8EPv with equivalent weight of 8.1100
152 micron (6 mil) layer of E. e, i! vI material is 6m long and 6.7 denier ΩPT
It was lined with porous paper made from a 50,150% by weight blend of bleached kraft pulp with FE filaments and 630-Canadian standard latitude. This thickness is 1
It is 19 microns (4.7 mils) and weighs 33.8
g/m" (1 oz/yd1). The laminate was prepared as in Example 1 [also in the heating zone, a vacuum was applied from the underside of the porous release paper to remove the molten TFE/PSEPVE. The entire sheet of porous reinforced paper [2] was suctioned down, thereby completely encapsulating the reinforcing fabric. The laminate did not leak even after hydrolysis. It was evaluated in a small chloralkali bath as in Example 1 except that the current efficiency was 96 N and the voltage was 3.6 after 7 days of operation.
8 is Ruto. Example 7 U.S. Patent Application No. 121°461 dated February 14, 1980
A laminate was manufactured using the same reinforcing material as in the previous example except that the laminator described in No. 1 was used. The layers were as follows: A, 10-80 EW□TFE/EVE (7) 51
Micron (2 mil) layer. B, 1100EWO'l'FE/)'5EPVB's 51
Micron (2 mil) layer. 50150 PTPE/Kraft as in C0 Example 6. 1), 1100 EWO'l'FE/PSEi'VE
(7) 51 micron (2 mil) layer. The laminate was hydrolyzed and evaluated in a small chloralkali bath at a temperature of 80°C. Other conditions are Example 1
was the same as After 13 days of operation, current efficiency is 96.5%
and the voltage was 3.62 volts. Comparative Example This comparative example is TF! which does not contain temporary fibers. The effect on cell voltage when using a non-woven reinforcing material from the P'l'E filament is shown. It was the same. The paper is 110 microns (4,3 mil) thick and 1] OI/m” (3,2
After hydrolysis with a basis weight of 6 g/yd8), it was evaluated in a small chloralkali bath. After 7 days this has a current efficiency of 93.1% and a current efficiency of 4.16&
The root potential is shown. The ion exchange membrane of the present invention is technologically advanced compared to conventional membrane methods. It exhibits improved performance characteristics when used as a membrane in a chlor-alkali bath, including operation at low voltage and current efficiency, ie, low power consumption. Substantial savings in operating costs are therefore achieved due to lower power consumption. Patent Applicant: 1 person other than E.I. DuPont de Nemois and Pa Company Continued from page 1 Priority claim: November 12, 1981 ■United States (US)
■319991

Claims (1)

[Claims] 1. -CUOR and/or -80! At least two layers of fluorinated electropolymer having a VV functional group (wherein generally lower alkyl and W is F or CI) are present in adhesion to the fluorinated electropolymer, and embedded therein. at least a first said layer having -CUOR groups and a second said layer having -80,W functional groups are present and used in the production of said layers. The total thickness of at least two of the layers of fluorinated electrolyte is in the range of about 50 to 250 microns, and the web of support material is in the range of about 25 to 125 microns.
It has the thickness of Miku and has reinforcement and temporary (sacr)
1. Membrane impermeable to hydraulic flow of liquid, characterized in that it consists of both i-ficial and i-ficial members. 2. The membrane according to claim 1, wherein the membrane comprises a perfluorinated polymer. 3. The -eooa functional group is a part of -0-(CF, 1m2000R shallow group [where m is 2 or 3]) and 1
and the -8O,W functional group 10F, -CF, -80.
The membrane according to claim 2, which is a part of W residues. 4. The web of support material is a woven fabric, the reinforcement thereof is a perhalocarbon polymer system with a 50 to 600 denyl and an aspect ratio within the range of 2 to 20; Target number is 40-100
denyl fugitive yarn, the woven fabric having a yarn count in the range of 1.6 to 16 perhalocarmene polymer systems/as in each of the warp and weft and 1:l to 10 in each of the warp and weft. Claim 3g4 having a ratio of fugitive yarn to perhalocarbon electrolyte system in the range of :1.
The membrane described. 5. 5. The membrane according to claim 4, wherein the bar-halocarbon vehicle combination system is a perfluorocarbon combination system. 6. 1i*fabric has a thickness of 50 to 100 microns
The membrane according to claim 5, having a barfluorcarb heptad system of 200 to 400 denyl and an aspect ratio in the range of 5 to 1o. 7. The cough woven fabric has a thread count in the range of 6 to 8 perfluorocarbon fibers/1 in each of the warp and weft and 2:1 or 4:1 in each of the warp and weft.
7. The membrane of claim 6 having a ratio of fugitive yarn to perfluorocardan polymer system of . 8. The membrane according to claim 7, wherein the perfluorocarbon polymer system is a monofilament of polytetrafluoroethylene. 9. The bar fluorocarbon vehicle system has a substantially rectangular cross section, an aspect ratio in the range of 6 to 8, and a thickness of about 35 to 40 microns, and The ratio of yarn to perfluorocarbon East combined system is 4:
1. The membrane according to claim 8, which is 10. The membrane of claim 7, wherein each said perfluorocarbon polymer system is multi-stranded. 11, -0-(OF,)m-COOR and/or -U
21 of a fluorinated polymer having P, -CF, -80,W, the first layer having a thickness in the range of 13 to 75 microns, and the second layer having a thickness in the range of 50 to 125 microns. The patent li! has a thickness in the range of microns and the total thickness of said layer of fluorinated polymer is in the range of 75-150 microns! The membrane described in item 7 of the range of Kyoto. 12, m is 2 and the -SO,W functional group is 10-
CF, -CF, -80. The membrane according to any one of claims 8 to 11, which is a part of W residues. 13. A membrane according to any of claims 8 to 11, wherein the woven fabric is present at least primarily in the second layer of perfluorinated polymer. 14. The claim according to any one of claims 8 to 11, wherein the temporary thread is a rayon thread. 15. The web of support material is a nonwoven paper, the reinforcing member is 10-90% by weight of perhalocarbon electrolyte fibers, and the temporary member is 90-10% by weight of fugitive fibers.
3. The membrane of claim 3, wherein the layer has a basis weight of about 25 to 125 g/c*". 16. The membrane of claim 3, wherein the perhalocarbon-rich fibers are perfluorocarbon polymer fibers. 15. The membrane of claim 15. 17. The nonwoven paper has a thickness of 50 to 75 microns and a thickness of 25 to 75 microns.
Claim 16 with a basis weight of 50 g/m”
Membrane described in section. 18. The membrane of claim 17, wherein the barfluorocarbon polymer fibers are 5 to 10 denyl and have a length of 3 to 20 meters. 19. The membrane according to claim 18 of the patent, wherein the fugitive fibers are cellulosic kraft fibers having a degree of freedom within the Canadian Standard range of 500 to 7001. 20. The membrane of claim 19, wherein said nonwoven paper comprises 25 to 75% by weight of said perfluorocarbon polymer fibers and 75 to 25% by weight of said kraft fibers. 21, -0-(CF, lm-C0OR and/or -CF
, -CF, -8O,W are present, the second layer having a thickness in the range of 13 to 75 microns, and the second layer having a thickness in the range of 50 to 125 microns. having a thickness in the range of microns, such that the total thickness of the layer of fluorinated polymer is 7.
Claim 1 within the range of 5 to 150 microns
The membrane according to item 9. 22, m is 2 and the -80,W functional group is 10-C
22. The membrane according to claim 20 or 21, which is a part of F, -OF, -8o, W residues. 23. The membrane of claim 20 or 21, wherein said fabric is at least predominantly present in said second layer of perfluorinated polymer. 24, the iron film is coated with a gas-containing electrocatalyst composition on at least one surface thereof.
and a liquid-permeable porous layer. 25. The iron film is further coated with gas on at least one surface.
and a liquid-permeable porous non-electrode layer. 26, -COOM and/or -80,! Adjacent 1- of fluorinated 1 complexes having 114 functional groups (where M is H, Na, K or NH4) adhere to each other. an ion conversion membrane impermeable to hydraulic flow of a liquid, comprising at least two layers comprising a web of support material embedded therein, a first said layer having -000M functional groups and a web of support material embedded therein; There is at least a second said layer having 805M functional groups, and the total thickness of at least two layers of fluorinated polymer is one COOR and/or - used in the production of the iron film.
SO, W functional group [where R is lower alkyl and/
or W is F or C1] in the range of 50 to 250 microns;
The web of support material has a thickness of about 25 to 125 microns and an aperture of at least 50% and comprises a stiffener defining a window area therebetween and a conduit within the membrane. An ion exchange membrane, characterized in that (channel) extends from the window region to a blind region, where the reinforcement is located near the first layer. 27. The membrane according to claim 26, wherein the # layer comprises a perfluorinated polymer. 28, the -〇〇R1 functional group is -0-(CFt)rrr
is part of the -COOR residue [where m is 2 or 3], and the fi-80,W functionality is -OF, -C
Claim 2, which is a part of F, -80, W residues
The membrane according to item 7. 29. The web of support material is a woven fabric, the reinforcement is a barhalocargen polymer system having a denier of 50 to 600 and an aspect ratio in the range of 2 to 20, and the woven fabric has warp and weft yarns. each having a thread count in the range of 1.6 to 16 threads/υ perhelocarbon polymer system;
the threads of the warp intersect the threads of the weft at an intersection, each pair of adjacent intersections defining a thread segment, and at least one conduit extending from the window area to the cough blind area in at least half of the thread segment; 29. Membranes according to claim 28, which are located adjacent to each other. 30. The membrane of claim 29, wherein there is at least one said conduit extending from the window area to the blind area adjacent to all of said yarn segments. 31. The membrane according to claim 30, wherein the perfluorocarbon polymer system is a perfluorocarbon polymer system. 32. The woven fabric has a thickness of 50 to 100 microns, and the perfluorocarbon polymer system has a denyl of 200 to 400 and an aspect ratio in the range of 5 to 10. membrane. 33. The membrane of claim 32, wherein the woven fabric has a thread count in the range of 6 to 8 perfluorocarbon polymer threads/m in each of the warp and weft threads. 34. 34. The membrane of claim 33, wherein the i7 perfluorocarbon polymer system is a monofilament of polytetrafluoroethylene. 35, the perfluorocarbon electrolyte system has a substantially rectangular cross section, an aspect ratio in the range of 6 to 8, and about 35 to 40
35. A membrane according to claim 34 having a thickness of microns. 36. The membrane of claim 33, wherein each said peruffled carbon polymer system is multi-stranded. 37, 0 (CF*)m C0OR and/or -
There are two layers of fluorinated polymer having CF, -CF, -80,W, the first layer having a thickness in the range of 13 to 75 microns, and the second layer having a thickness in the range of 50 to 75 microns. has a thickness in the range of 125 microns and the total thickness of the layer of fluorinated electroalloy is 7.
Claim 3 within the range of 5 to 150 microns
The membrane according to item 3. 38. The membrane of claim 37, wherein the conduit opens into an exposed surface of the second layer.゛39. 34. The membrane of claim 33, wherein said conduit has a nominal diameter of 10 to 50 microns. 40, m is 2, and the -80,M functional group is 10-CFt-CF, -80. 38. A membrane according to any of claims 34 to 37, which is part of the M residue. 41. The membrane of any of claims 34-37, wherein said woven fabric is at least primarily present in said second layer of fluorinated polymer. 42, the web of support material is a nonwoven paper, the reinforcement is a perhalocarbon polymer fiber, and
43. The membrane of claim 28 having a basis weight of 112.51 layer m''. 43. The membrane of claim 42, wherein the perhalocarbon fibers are perfluorocarbon polymer fibers. 44, the nonwoven paper has a thickness of 50 to 7.5 microns; and 2.
5-45. 44. The membrane of claim 43 having a basis weight of li'/m'. 45. The membrane of claim 44, wherein the perfluorocarbon polymer fibers are 5 to 10 denyl and have a length of 3 to 20 inches. 46, 0 (CF * 1m C0OR and/
or there are two layers of a fluorinated polymer having -CF, -CF', -80,W, said second layer having a thickness in the range of 13 to 75 microns [7, said second layer 45. The membrane of claim 44, wherein the layer has a thickness in the range of 50 to 125 microns [2] and the total thickness of the layer of fluorinated polymer is in the range of 75 to 150 microns. 47. The membrane of claim 45, wherein said conduit has a nominal diameter of 1 to 20 microns. 48, m is 2 and the -8O,M functional group is 10-
The pattern according to claim 46 or 47, which is a part of CF, -CF, -80,M residue. 49. The membrane of claim 46 or 47, wherein said woven fabric is at least primarily present in said second layer of fluorinated polymer. 50. The membrane of claim 26, wherein the linear membrane further comprises a gas- and liquid-permeable porous layer of an electrocatalytic composition on at least one surface thereof. 51. The membrane of claim 26, wherein the linear membrane further comprises a liquid-permeable porous non-electrode layer on at least one surface thereof. 52. The linear membrane further comprises a gas- and liquid-permeable porous layer of a cathode electrocatalyst composition on the exposed surface of the second layer; and 37. The membrane of claim 37, comprising a gas- and liquid-permeable porous non-electrode layer. 53, an anode chamber, an anode located within the anode chamber, a negative electrode chamber, a cathode located within the cathode chamber, and Claim No. 26.29.30.35.37.39.42 located between the chambers.
．． 46. An electrochemical cell comprising the wire membrane according to paragraph 47.50 or 51. 54. The electrochemical cell of claim 53, wherein the spacing between said anode and said negative electrode is not greater than about 3 meters. 55. The electrochemical cell according to claim 54, wherein a wire membrane is brought into contact with at least one of the anode and the cathode. 56. The electrochemical cell according to claim 55, wherein a wire membrane is brought into contact with both the anode and the cathode. 57. In a method for producing caustic and chlorine by electrolyzing salt water in a chlor-alkali tank consisting of an anode, an anode chamber, a cathode, an anode chamber, and a fluorine-containing cation exchange membrane for separating iron content, the method claimed as a linear membrane Range No. 26.29.3
0, 35.37.39.42.46.47.50 or 5
An electrolysis method characterized by using the membrane according to item 1. 58. The method of claim 57, wherein the spacing between the anode and the nuclear cathode is not greater than about 3 meters. 59. The method of claim 58, wherein a wire membrane is brought into contact with at least one of the anode and the cathode. 60. The method of claim 59, wherein the membrane is contacted with both the cough anode and the cathode.