JPH09510391A - Method for forming thin durable coatings of ion-containing polymers on specific substrates - Google Patents

Abstract

  (57) [Summary] A non-evaporation method for coating ion-containing polymers on a given substrate and products produced thereby. The method comprises contacting a substrate with a dispersion or solution of an ion-containing polymer, in particular a solventless dispersion of perfluorosulfonic acid ionomer, and then a substrate wetted with the dispersion or solution and a substrate. It basically comprises the step of contacting with a solution of salt or strongly ionizable acid of sufficient concentration to form an adhesive coating of ion-containing polymer on the material.

Description

DETAILED DESCRIPTION OF THE INVENTION Method of Forming a Thin Durable Coating of an Ion-Containing Polymer on a Specific Substrate The present invention relates to a method of forming a thin coating on a specific substrate, and made by the method. Regarding goods. More specifically, but not exclusively, the present invention employs a surface active dispersion of an ion-containing polymer that wets the particular substrate to be coated onto such a substrate. The method of forming a coating of Examples of known ion-containing polymers include sulfonated polystyrene, copolymers of ethylene with α-β unsaturated carboxylic acids such as acrylic acid or methacrylic acid and perfluorocarbon ionomers. Perfluorocarbon ionomers include sulfur-based functional groups, phosphorus-based functional groups and carboxylic acid or carboxylate functional groups. All of these materials are currently available with the exception of phosphorus-based perfluorocarbon ionomers. Perfluorinated ionomers having sulfonic acids or salts thereof as functional groups are of particular interest, and commercial examples of such ionomers are available from EIDuPont de Nemours & Co., Inc. Have been manufactured in the acid form under the trade name Nafion (TM). The Dow Chemical Company produced ionomers with shorter side chain (acid form) structures. The preparation of these ionomers is well documented in the literature, for example in US Pat. Nos. 4,358,545 and 4,940,525, and is well known in the art of perfluorinated ionomers. Dispersions of copolymers of ethylenically unsaturated carboxylic acid monomers and non-acidic ethylenically unsaturated monomers are well known in the art, and are described, for example, in U.S. Patents 3,799,901 and 5,206,279 and summarized therein. It is described in the literature. Ethylene-acrylic acid copolymers are commercially available, inter alia, from The Dow Chemical Company under the Primacor ™, which contains from 3 to 20% by weight acrylic acid monomer. Dispersions of ethylene acrylic acid copolymers are available from Morton International under the Adcote ™, but a high acid polymer (usually 20% by weight acrylic acid monomer) is used with an aqueous ammonium hydroxide solution at 95- It is also prepared by stirring in a closed container at 110 ° C for 30 to 90 minutes. Normally, 0.8 mole of ammonium hydroxide is used per mole of acrylic acid to produce a dispersion containing 25 wt% ethylene acrylic acid copolymer. Surfactant dispersions for coating polytetrafluoroethylene, polyethylene or polypropylene are prepared, for example, by diluting 4 parts by weight of this 25% by weight aqueous dispersion with 96 parts by weight of an equal weight mixture of water and ethanol. Can be done. Partially sulfonated polystyrene (or PSP) can be prepared, for example, by the procedure described in US Pat. No. 3,072,618. The SPS polymer thus prepared and containing 1.2 meq / g dry polymer will be dissolved in 1,4-dioxane. A partially sulfonated polystyrene polymer surfactant solution or dispersion is then prepared by diluting a 2 wt% solution of the polymer in 1,4-dioxane with the same volume of deionized water, It can be visually tested to prepare good coatings on substrates such as polytetrafluoroethylene, polyethylene and polypropylene. Perfluorosulphonic acid ionomer dispersions and perfluorosulphonate ionomer dispersions have previously been described by Martin et al. In U.S. Pat. And the resulting solids are redispersible in a variety of solvents), Martin et al., U.S. Pat.No. 4,661,411 (250 ° C., high pressure, acid form of the ionomer), Grot U.S. Pat. 4,453,991 and references cited therein (acid or salt forms), Moore and Martin, "Morphology nad Chemical Properties of the Dow Perfluoros ulfonate Ionomers", Macromolecules, vol.22, pp.3594-3599 (1989), and Moore and Martin “Chemical and Morphological Properties of Solution-Cast Perfluorosulfonate Ionomers”, Macromolecules, It has been manufactured by the method described in vol. 21, pp. 1334-1339 (1988). Dispersions of Nafion ™ ionomers are also commercially available in various equivalents using lower alcohol / water combinations as the liquid medium or solvent. Thin films have previously been produced using these perfluorocarbon ionomer dispersions. It is, for example, the Martin and Grot patent mentioned above (suitable substrates are catalyst supports such as alumina, silica, zeolites, carbons, etc., perhalocarbon or glass-containing fabrics, ion exchange membranes or porous diaphragms, and wires or Wire mesh electrodes), Darlington et al., U.S. Pat. No. 4,680,101 and DuBios et al., U.S. Pat. No. 4,720,334 (diaphragm support), and Szentirmay et al. ． Chem., Vol. 58, No. 3, pp. 661-662 (March 1986). However, none of the membranes produced by these previous methods was completely satisfactory. Especially when a substrate having a non-uniform or irregular surface was to be coated, an excess amount of ionomer was required to completely coat the substrate. The adhesion strength and durability of these films to the underlying substrate was also less than desired. The present invention is directed to a new and improved method for forming thin films of ion-containing polymers on a particular substrate, particularly ionomers in the form of perfluorosulfonates, which method comprises a colloidal interface of ion-containing polymers. Contacting the active dispersion with the substrate, and then contacting the dispersion-wetted substrate (while still wet with the colloidal dispersion or solution) with a solution of a strongly ionizable acid or salt. That is, the solution is at a concentration sufficient to produce an adherent film of ion-containing polymer (which can, but need not be, continuous) to be formed on the surface of the substrate. Including, including. This coating is typically on the order of less than 100 nanometers thick, and desirably on the order of 5-10 nanometers thick. An optional additional step involves exchanging the ionomer cations after the first contact with a solution of the salt or acid, which may, for example, be used to disperse the wetted substrate of the dispersion with the same or different salts. By contacting with a solution, for example, a potassium salt solution rather than a sodium salt solution, where the freshly exchanged form of the ionomer is less effective than the initial form when initially coating the substrate, It is either versatile for a particular end use or further processing, or has completely more specific qualities or characteristics than the original salt or acid form. A further optional step may include treating the coated substrate at elevated temperature to provide improved coating adhesion to the substrate or for other purposes as described below. The subject "dispersion" has the particular properties of a true solution, as described in Grot U.S. Pat. No. 4,433,082, but the "dispersion" results in these liquids of ion-containing polymers. One of ordinary skill in the art will understand that the composition is not to be construed as limited. As such, amphipathic ion-containing polymers that can be included in surface-active dispersions are generally of interest and are those that have low ionic functionality (eg, those containing less than 20 mol% ionizable monomer). The containing polymers are of particular interest because they form an essentially continuous coating on a variety of substrates. Ion-containing polymers are also useful which, when made into a dispersion or solution, do not fully wet a given substrate, i.e. the contact angle of the substrate wetted with the dispersion or solution does not approach zero. Not very desirable. Acid solutions that can be used to subsequently contact a dispersion or solution-wet substrate by the method of the present invention are conventionally known in the art as "strong acids" or Includes aqueous solutions of classified acids such as nitric acid, hydrochloric acid or sulfuric acid. However, preferably a solution of salt will be used. The optimal concentration of salt in the salt solution used in certain embodiments depends on the salt used, but is typically greater than about 1% by weight salt solution, preferably from about 5% by weight solution to saturated solution. Is. Salts known to be suitable for use in the present invention include any such as sulfuric acid, fluoride, chloride, bromide, iodide, carbonic acid, acetic acid, hydroxide, nitric acid or thiocyanate ion. Includes cations such as hydrogen, alkali metals, alkaline earth metals and transition metals, ammonium and alkylammonium cations in water-soluble combination with anions. For perfluorocarbon ionomer coatings, more specifically, sodium chloride, sodium carbonate, sodium acetate and sodium bisulfate are all of particular importance for forming essentially continuous coatings on substrates such as PTFE. I knew it was. However, as mentioned above, it is desirable to exchange the sodium in the ionomer for a different cation by contacting the sodium-exchanged perfluorosulfonate ionomer coating with a solution of a different cation after the coating is first formed. Let's do it. A specific example in which it would be desirable to perform this additional step would be as follows. As also suggested above, the adhesion and durability of the ionomer coating is improved in preferred embodiments of the invention by annealing at elevated temperature. The optimum annealing temperature to be used in any given application will depend on the structure of the ionomer, the counterion, and the thermal properties of the substrate. However, in general, annealing the coating near the ionic glass transition temperature (Tg) of the subject ionomer, or near the Tg or crystalline melting point of the polymeric substrate, but below the decomposition temperature of the ionomer and substrate. This achieves the greatest improvement in deposition on polymer substrates. In certain applications of the present invention, one or more layers of ionomer, for example, where the performance or properties of the coated substrate are known or expected to be, to some extent, thickness dependent. It would be desirable to use a coating. The method of the present invention involves contacting a coated substrate with a solution of a second salt containing a different cation to increase the contact angle of the coated substrate prior to applying the further coating of the ionomer. (As it does at the time of application of the first coating, i.e., contacting the dispersion and then contacting the first solution of the first salt), and then the coated substrate. Can be heat treated to further increase the contact angle for application to provide multiple coatings on a given substrate. Alternatively, the heat treatment step alone may be sufficient to raise the contact angle to the extent that a further coating can be applied. This heat treatment is generally performed at a temperature below that recommended for the adhesion improving step by annealing, and preferably after the final coating application, the annealing step is performed. The ionomer that is preferably used when coating a particular substrate will depend on the application of the article being coated. For example, perfluorocarbon ionomers are generally preferred when chemical and thermal stability is a necessary or desirable property, but in other applications where the chemical and thermal stability of these materials is not required, sulfone may be used. Polystyrene and ethylene acrylic acid copolymers would be preferred due to their low cost. However, it is contemplated that for the particular applications contemplated herein, the coating methods and coated articles of the present invention will be based on colloidal surfactant dispersions of perfluorosulfonic acid ionomers or perfluorosulfonate ionomers. EIDu Pont de Nemours & Co. Inc. Of the type sold under the trade name Nafion ™ from The Dow Chemical Company by The Dow Chemical Company and represented by the above structural formula, is a sulfur-based ionomer of shorter side chain. Is also appropriate. The shorter side chain ionomers of The Dow Chemical Company are presently more preferred, and more generally, when the maximum ionic content and surface wettability are desired, the novel ionomers described in more detail below. It is more preferable because it can be used in a coating method of a solventless (organic) perfluorocarbon ionomer. Dispersions are commercially available or have previously been prepared using various equivalents of perfluorosulphonic acid or perfluorosulphonate ionomers, but preferably the perfluorinated ionomers used herein are from 500 to It will have an equivalent weight in the range of 1500 and most preferably will have an equivalent weight in the range of 550-1200. Any method for producing a colloidal dispersion of ionomers having these equivalent weights can be suitably used, e.g. solid ionomer, water and lower alcohol ( For example, it is dissolved in a mixture of ethanol or propanol (such a method is described in US Pat. No. 4,433,082 to Grot, supra). Commercially available dispersions of Nafion ™ ionomers in lower alcohol / water solvent systems may also be used in these equivalent amounts. Preferably, however, dispersions using only water as solvent will be prepared from at least certain of these ionomers for coating certain substrates. Fully aqueous dispersions are preferred. This is because the flammability, inhalation and discharge / environmental concerns associated with ethanol / water solvent systems are not present when using water as the solvent for these dispersions. Shorter side chain ionomers manufactured by The Dow Chemical Company are particularly preferred for use in solventless coating processes, as previously mentioned. This is because this ionomer has a high yield in water alone at an equivalent weight of 550 to 1000, and in particular an equivalent weight of 550 to 800, where the yield is of the ionomer solids effectively dispersed in the liquid solvent. The amount was divided by the total amount of ionomer solids that was attempted to disperse), because it was possible to disperse under mild conditions. In this regard, the Grot '082 patent describes an ionomer in the form of up to 10% by weight of perfluorosulfonic acid in a closed vessel at a temperature of at least 240 ° C with stirring, in water alone (ionomer 1025 to It is contemplated that dispersions with equivalent weights in the range of 1500) can be produced. An example illustrating this method is 370 lb / in. ² It showed a pressure above (2.5 MPa) and the yield of the dispersion at room temperature was about 27% (after 100 hours stirring at 240 ° C. and 370 psi) and 48% (after 18 hours at 235 ° C.). In contrast, room temperature dispersions containing 1 to 3 wt% of the shorter equivalent side chain ionomer in the lower equivalent weight acid form described above have a temperature of 170-200 ° C. and 110 pounds / inch. ² It can be prepared for the solventless (organic) coating method of the present invention by stirring at absolute pressure (ps ia) (0.76 MPa, absolute pressure) to 225 psia (1.6 MPa absolute pressure) for 1 to 3 hours, 800 equivalents of ionomer showed yields of 70-95% by weight or higher. Preferably, the desired equivalent amount of powdered ionomer is mixed with water in a closed vessel and heated to a temperature of 180 ° C to 185 ° C, stirred for about 2 hours, and the pressure is 145 to 165 psia (1.0 MPa absolute to 1.1 MPa). Absolute pressure). There are many types of substrates that can be coated with ionomers by the method of the present invention, and desirably, polytetrafluoroethylene, polyvinylidene fluoride, fluorinated ethylene-propylene copolymer (FEP), poly (vinyl chloride), glass, Fibers, powders of polypropylene, carbon, steel, platinum, chlorotrifluoroethylene or perfluoroalkoxy vinyl ether-tetrafluoroethylene copolymers (for example those sold under the Teflon PFA ™ by EIDuPont de Nemours & Co., Inc.) , Fabrics or articles. Obviously, as the invention relates to coatings, articles having an outer layer or coating of any of the above mentioned substrate materials may also be suitably coated with the ionomer according to the invention. Even more generally, the method of the present invention provides an ionomer coating as a transition surface between any two materials whose surface forms a high surface energy interface (in the absence of the ionomer coating). It can be used for. One prominent example of such an interface can be the interface between a fluoropolymer matrix material and a reinforcing filler material such as carbon, ceramic or glass, which can be, for example, PTFE bushings, bearings and low dielectric constants. It is often used in PTFE to reduce cold creep, reduce the coefficient of thermal expansion, and improve the compressive strength of filler-free PTFE in circuit boards. The ionomer coating method of the present invention is often corona discharge, which is often used to make fluoropolymer surfaces more wettable and thus more bondable, or corroded by sodium amide or sodium naphthide. It can be a simple alternative to treating chemicals. For other particularly useful applications of the invention, in proton exchange membrane fuel cells, the catalytic sites must be accessible to the reaction gas and the proton conductor. A thin (eg, less than micrometer) coating of perfluorocarbon on the catalyst (supported or unsupported) provides a proton conductor without interfering with gas diffusion to the catalyst-ionomer interface. The perfluorocarbon ionomer coatings possible according to the present invention have also been used to provide maximum proton conductivity and maximum interfacial area in the preparation of electrolytic capacitors such as those described in Sarangapani et al. U.S. Pat.No. 5,136,474. sell. However, a particularly preferred application of the present invention is the use of an ionomer coating or a plurality of polytetrafluoroethylene (PTFE) fibers and / or powders to render the polytetrafluoroethylene (PTFE) fibers and / or powders water-wettable. Of such coatings, especially perfluoroionomer coatings. In this regard, PTFE has many desirable attributes including excellent chemical stability. However, there have been major obstacles to the use of PTFE in certain applications, such as in the development of non-asbestos diaphragms in chlor-alkali cells due to the hydrophobic nature of PTFE. Various efforts have been made to eliminate or overcome the hydrophobicity of PTF E by adding ion exchange materials in chlor-alkali diaphragms. Examples of these efforts can be found in U.S. Pat. No. 4,169,024 to Fang, where PTFE (or a similar fluoropolymer) in powder or fiber form is used to support unsupported porous or non-porous films. , Chemically modified in a coating or porous reinforcing structure (ie, diaphragm) on an inert fabric by reaction with a sulfur or phosphorus containing compound. DuBios et al., U.S. Pat.No. 4,720,334, is also representative, and based on the total weight of fibrillated fluoropolymer and ionomer, 65-99% by weight fibrillated fluorocarbon polymer, such as PTFE, and 1-35% by weight. Of fluorocarbon ionomers, preferably containing carboxylic acid, sulfonic acid, alkali metal carbonate or alkali metal sulfonate functional groups, and optionally further comprising a wettable inorganic particulate material. The diaphragm is dried and fixed on the underlying cathode by heating for a period of time below the firing temperature of PTFE. The ionomer is coated on either or both of the fluorocarbon fibrils and inorganic particles by co-deposition from a slurry containing the ionomer as a solid, gel or solution, and then deposited from the slurry, or , The fluoropolymer can be incorporated into the diaphragm by being extruded in a mixture with the fluorocarbon before it is fibrillated. A specific coating method for coating PTFE fibrils has been described, in which a solution of ionomer in a water-miscible solvent and PTFE powder are mixed under high shear and then blended with water and a specific surfactant. Dispersing the fibrils that are being coated by. The material is then deposited on the cathode from the resulting slurry. According to one aspect of the coating method of the present invention, in contrast, the PTFE powder or fiber is preferably in the form of a short side chain acid form having an equivalent weight of 550 to 1200, produced by The Dow Chemical Company, supra. It is first mixed with a colloidal dispersion of perfluorosulfonate ionomer made from the ionomer. This colloidal dispersion is prepared by, for example, acid-washing an ionomer membrane in the acid form, rinsing it with deionized water to neutrality, and then dipping it in sodium hydroxide to remove the ionomer membrane from sodium ionomer. It can be produced by converting to the salt form. The membrane is then rinsed until neutral and dried, after which the desired weight of film is placed in a glass liner and mixed with a sufficient amount of a suitable solvent, such as a mixture of ethanol and water. , Preferably a solution or dispersion having an ionomer concentration of 5.0-7.0% by weight. After sealing the inside of the stainless steel reactor and purging with nitrogen, the reactor is stirred and heated to a temperature of the order of at least 160 ° C to 180 ° C for 1 to 3 hours, the pressure of 1 liter reactor is 180 ~. 220psig (1.2MPa gauge pressure ~ 1.5MPa gauge pressure). The reactor is then allowed to cool, the excess pressure is released, and the contents are filtered through a 60-80 micron glass filter. The resulting thick dispersion is then diluted with an ethanol / water mixture to finally provide the desired preferred dispersion with 1% by weight perfluorosulfonate ionomer. Alternatively (and preferably), a perfluorosulfonyl polymer in powder form may be used in place of the ionomer described above, and the powder is hydrolyzed in sodium hydroxide and dissolved as described above and processed. To be done. Other known methods for making dispersions of perfluoroionomers may also be used without limitation. The contact between the powdered PTFE base material and the alcohol / water based dispersion produced by this method results in the dispersion and PTFE powder having a weight ratio of ionomer solids to PTFE of 0.015 to 1 on a dry basis. Including mixing. This ratio can be adjusted to be sufficient to obtain a dough-like handleable mass. When PTFE fibers, coupons or fabrics, etc. are included, these substrates are, of course, sprayed with or immersed in the ionomer dispersion and the excess may be removed prior to contact with the salt solution. . The liquid-coated substrate is then directly agitated in salt solution (in the case of PTFE powder or fiber) or directly dipped in salt solution (in the case of coupons etc.) without being dried. ). Suitable salt solutions (for alcohol / water based dispersions or ionomer dispersions in water only for coating PTFE material to make it wettable by water) are water and strong acid. It is formed from a water-soluble salt of an alkali salt, an alkaline earth salt or a transition metal salt, and an ammonia salt of ammonia, a primary, secondary, tertiary or quaternary amine. Preferred salt solutions are prepared from water-soluble sodium and magnesium salts to form the initial coating on PTFE, and among these (shown above) sodium chloride, sodium acetate, sodium carbonate and bisulfate. Sodium is particularly preferred. To obtain maximum water wettability, or to add the next coating, contact the coated PTFE with a potassium or zinc salt solution and add the next coating at elevated temperature, e.g. It is preferable to perform heat treatment at a temperature of up to 300 ° C. for 20 to 30 minutes. The single-coated substrate is then contacted with the dispersion, exposed to a sodium or magnesium salt solution, rinsed, exposed to a potassium or zinc salt solution and heat treated until this is the desired final coating applied. Continued and the final heat treatment is an annealing treatment of the coated substrate. The quality of the ionomer coating produced according to the present invention is assessed by the contact angle on the coated substrate, which includes the ionomer concentration in the colloidal dispersion, the solvent composition of the dispersion, and the temperature, salt concentration and salt solution. Ultimately affected by pH. Each of these variables interacts with each other and with the type of salt and the structure of the ionomer. However, one of ordinary skill in the art would follow these for certain applications, such as coating other substrates than PTFE and / or for purposes other than imparting water wettability thereto, according to the approach of the exemplary embodiments provided below. It is expected that the optimal combination of the variables of can be determined. A coating of 800 equivalents of perfluorosulfonate ionomer (obtained from a short side chain perfluorocarbon ionomer from The Dow Chemical Company) on PTFE was applied to prepare an alcohol / water based ionomer prepared as described above. In order to make the dispersion essentially water-wettable permanently, 0.25 to 2.0% by weight of the ionomer should currently be dispersed in an aqueous ethanol solution containing 25 to 100% by volume of ethanol. , And it seems that the salt solution should ideally be 16-25% by weight sodium chloride in water. Most preferably, for the PTFE sample being annealed, the ionomer dispersion should contain 1.6 wt% ionomer in a mixture of 63 vol% ethanol in water and the salt solution should be at a temperature of 65 ° C. Should be a 25% by weight aqueous solution of sodium chloride. For PTFE samples that are not about to be annealed, the best results are of ionomer dispersions containing 1.8% perfluorosulfonate ionomer in a 60/40% mixture of ethanol / water and 25 wt% sodium chloride at 55 ° C. Obtained in aqueous solution. The solventless coating method of the present invention (i.e., using only water as the liquid medium of the dispersion) is preferred and can be carried out by several methods depending on the type of ionomer used and the nature of the dispersion used. be able to. For example, for short side chain ionomers produced by The Dow Chemical Company, the continuous coating process is initially and preferably from 1 to 10 ionomers in the form of perfluorosulfonic acid having 550 to 1000 equivalents, especially 550 to 800 equivalents. Preparing a dispersion containing 3% by weight in water. Alternatively, the available alcohol / water based dispersions are treated conventionally to remove alcohol. When the ionomer is a Nafion (TM) type perfluorosulfonic acid ionomer, the dispersion initially has less than 10% equivalent ionomer from 550-1500 under the methods and conditions defined in US Patent 4,433,082 to Grot. Alcohol / water based dispersions prepared either in water at 50 ° C. or more commonly marketed will be treated conventionally to remove alcohol. The resulting dispersion is then added to PTFE powder, for example, it has been subjected to high shear in water to yield PTFE particles of preferably uniform size, or, preferably, precut. PTFE powder or a mixture of PTFE in the form of PTFE powder / granulate and fiber. The mixture is then coated with the ionomer on the PTFE substrate, and when using a mixer blade tip speed of 800 ft / min (240 m / min) or higher for a sufficient time to form a homogeneous slurry. Substantially corresponding high shear. Care should be taken here that excessive mixing / shearing does not generate enough heat for the coated PTFE to start sticking. It is important to note that the subject liquid should be added to the PTFE, not the water, or the dispersion, to the PTFE. The resulting ionomer / PTFE solids ratio is generally 0.005: 1 or more by weight, preferably 0.005: 1 to 0.015: 1, where sufficient solids shear and PTFE ionomer. Sufficient ionomer and PTFE are present for a given volume of water to achieve the coating according to. This minimum solids level is reasonably expected to vary with different tip speeds and different conditions and different equipment, but can be determined by routine experimentation. Those skilled in the art of diaphragms do not require a rinsing step to remove lower alcohols from the coated PTFE material at this point, so the ionomer-coated PTFE can then be used in a stretching vessel for stretching non-asbestos diaphragms. It will be appreciated that it can be contacted in situ with the required salt solution. Alternatively, in other applications, the coated PTFE is removed from the salt solution, rinsed with water to remove excess salt, and air dried. However, more preferably, dried coated PTFE generally requires vigorous agitation to be re-wet, so coated PTFE for such other applications may be used in any rinse step. After, it is left moistened. As previously indicated, the durability and bond strength of ionomer coatings can be improved (to the extent that the coating is not rubbed by hand) when desired for a given application. It is by annealing the coated substrate at a temperature below the decomposition temperature of the ionomer coating. The optimum annealing temperature for a given application also generally depends on both the structure of the ionomer and the salt morphology, and the nature of the substrate. The adhesion of coatings to substrates is generally improved by annealing at or near the glass transition temperature of the ionomer. More preferably, in order to achieve the highest adhesion and durability in the ionomer coating of the polymer substrate, the annealing treatment is performed near the glass transition temperature (Tg) of the amorphous polymer substrate or in the crystalline polymer group. It will be done near the melting point of the material. Thus, 800 equivalents of PTF E coated with a short side chain perfluorosulfonate ionomer of the type manufactured by The Dow Chemical Company (having an ionic Tg of 250 ° C) has the highest degree of adhesion and durability. Generally, obtained by annealing the coated PTFE substrate at a temperature of 330 to 350 ° C. for 1 to 360 minutes, and for a polyvinylidene fluoride substrate coated with the same ionomer, preferred annealing conditions are 160 Maintaining a temperature of ~ 170 ° C for 1 to 360 minutes. However, with the reorientation of the equipment surface under these conditions, specific migration of ionomers in the substrate is expected, e.g., during calcination of ionomer-coated PTFE-containing chloro-alkali diaphragms to some extent. It should be noted that the benefit of improved adhesion to some extent can be negated because of the concomitant loss of convertibility. Consequently, in order to determine whether it is desirable to achieve such improved adhesion and durability for the end use, it is achieved at the given annealing process conditions for the given end use. Possibility of adhesion and durability should be weighed against the effects of reduced wettability and possible degradation of certain other properties. In chloro-alkali diaphragms using the above PTFE powders and / or fibers coated in a specific manner, these coatings in the form of alkali metal perfluorosulfonates have the diaphragm conventionally fired and bonded. It was found to remain stable and wettable after exposure to temperatures of 335-350 ° C., and the coating was essentially permanently affixed to the underlying PTFE substrate (coated and The usual cellophane applied to the annealed PTFE coupon is deposited to the extent that it does not visually remove the ionomer coating). Those skilled in the art will appreciate from the above that different ionomers are useful or desirable (for different backbone structures, different functional groups or different salts) in substrates other than PTFE, and in applications other than making the PTFE water-wettable. Different equivalent weights of the ionomers are useful or preferred, salt solutions of different composition, temperature and / or pH are useful or preferred, and the annealing treatment is not suitable or suitably requires different temperatures. You would appreciate what you would do. Due to the wide variety of substrates and ionomers contemplated herein, and the variety of applications in which the ionomer coatings of the present invention are potentially useful as transition surfaces, all of the interesting substrate, ionomer, and possible combinations of applications are identified. It is not possible, or useful, to fully describe here. However, from the above teachings and the examples below, it is believed that the invention may be practiced without further inventive techniques. Illustrative Examples Examples 1 to 4 Ionomer of the type manufactured by The Dow Chemical Company was added to CF in an emulsion polymerization system. ₂ = CF ₂ And CF ₂ = CFOCF ₂ SO ₂ Prepared by copolymerization with F. The resulting polymer was isolated, dried, pressed into a film, and hydrolyzed with 25 wt% NaOH to provide the ionomer in the form of sodium perfluorinated sulfonate. After washing to neutrality, cut the films containing 1.25 meq sulphone groups on a dry basis into smaller pieces, and 5 parts by weight (dry basis) of these film pieces on 95 parts by weight of ethanol and water, etc. The volume mixture was placed in a stirred pressure vessel. The container was then heated to 165 ° C for 4 hours with stirring. After cooling, the% solids of the resulting dispersion was determined to be 5.1 wt% by evaporating the weighed sample to dryness and weighing the residue. The colloidal dispersion was colorless and slightly cloudy. This dispersion was used to coat Teflon ™ 7C PTFE powder, PTFE film strips, polypropylene coupons and steel coupons. For powders, 100 g of powder was placed in a beaker and 700 g of dispersion was added to it. The mixture was stirred using a Lightning DS 1010 ™ stirrer at 600 rpm for about 20 minutes until a homogeneous slurry was obtained. The slurry was filtered using a medium to coarse filter paper and the wet cake was placed in a solution of 5 wt% sodium carbonate in water at room temperature and left for 15 minutes. The treated powder was then redispersed with a stirrer and collected by vacuum filtration. The filter cake was washed until neutral by dispersing the wet cake three times in deionized water with stirring in a high shear blender and collected by vacuum filtration. The powder was easily fully wettable and sank to the bottom of the blender when stirring was stopped. It was then observed that after drying, rewetting was achieved by stirring with deionized water. For comparison, powder samples were treated with the ionomer dispersion, filtered, and placed in a blender with deionized water. After mixing for 2 minutes, the powder was observed to lose its wettability and coat the blender walls and float on the surface of the water. For the coating of PTFE film, a 1/2 inch (1.3 cm) wide 3 inch (7.5 cm) long PTFE strip was washed with acetone and deionized water, most of the length being about 30% in an ionomer dispersion. It was immersed for 10 seconds, taken out, drained for a short time, and then immersed in a solution containing 5% by weight of sodium carbonate in water at room temperature for 10 seconds. The film was then washed with flowing deionized water to remove free material and excess salt and treated with an aqueous Safranine O ™ cationic dye solution from the dropper. The area treated with ionomer remained completely wet at all of these steps and absorbed the dye, leaving a red-pink colour. The color was not rinsed with deionized water but could be removed by adhesive tape or rubbing. Coated PTFE films that were not soaked in sodium carbonate solution dewet and did not retain dye. The polypropylene coupons coated with the dispersion also provided a wettable, homogeneously dyed surface when dipped in a 26 wt% sodium chloride and water solution at room temperature. The same was true for defatted steel coupons coated and dipped in the same 26 wt% sodium chloride solution. Example 5 A PTFE film was coated with the ionomer dispersion of Examples 1-4, immersed in a 5% by weight aqueous sodium carbonate solution at room temperature, and rinsed to remove free material and excess salt, but the film was dyed. Did not process. The film was then annealed in a Hewlett-Packard 5880 Gas Chromatograph oven by slowly heating from room temperature to 350 ° C (eg, at about 20 ° C / min) and holding at this temperature for 1/2 hour. , Then cooled to room temperature (usually over a period of 10 minutes to 2 hours). After cooling to room temperature, the film was treated with Safranine O ™ dye solution. The coated portion of the film absorbed the dye and became a red-pink colour, which was not removed by adhesive tape or rubbing. Heat-treated or annealed film (more specifically, its coated portion) is deionized at about 100 ° after cooling in air, about 88 ° after soaking in deionized water for 2 hours, and at 70 ° C. It was observed to have a contact angle with water of about 79 ° after soaking in water for 2 hours. It was observed that the uncoated film that underwent the same thermal cycle had a contact angle with water of about 126 ° upon cooling, and that this contact angle was essentially unchanged after 2 hours of immersion in water. It was Providing a PFTE substrate with water wettability is consequently preferable for coating and annealing treatments, for example, in the manufacture of chloroalkali diaphragms, stirring in water prior to operating the diaphragm cell. Thus, it may be preferable to soak or rewet the coated, annealed PTFE. The methods used to make these contact angle measurements, and the measurements made in the examples below, show that certain annealed coated PTFE coupons equilibrate in water at room temperature, generally for 16 hours or more. Including conversion. The unannealed sample was rinsed after coating and immersed in water until the contact angle was measured. A given coated and salt solution dipped PTFE coupon (annealed or unannealed) is then removed from the deionized water bath and pat-dried, followed by a Kernco Contact Angle Meter, The model G-1 contact angle measuring device was placed on the stage, and the contact angle with water of the coated coupon on the device was measured several times (10 to 14 measurements). When the subject coupons did not lie flat on the device, a hole punch was used to cut into 1/4 inch (0.6 cm) diameter discs and the contact angle was measured on the face of the disc not exposed to the punch. One measurement was made using the opposite edges of each disc, and the measurements were averaged for the coupons. Examples 6-20 Designed and conducted experiments to determine the effect of various conditions on coating the ionomer dispersion of the above example on PTFE with respect to the contact angle of coated PTFE and water. The variables used were the concentration of ionomer in the dispersion (range 1-5% by weight in a mixture of equal volumes of ethanol and water), the concentration of sodium chloride in aqueous salt solution (1-25% by weight in water), And the effect of repeating one or more layers of ionomer coating without heat treatment between these coatings. All solutions were at room temperature (about 25 ° C). For the general procedure followed in this designed experiment, the PTFE coupons to be coated were first washed with acetone, rinsed in deionized water, and dried. The coupons were then dipped into the ionomer solution, removed from the ionomer solution and drained for 5-10 seconds before being dipped into the salt solution. The coupon was then removed and rinsed in deionized water. If a second coating was to be applied, these steps were repeated without drying. The coupons were then air dried, heated to 335-345 ° C and annealed by holding at this temperature for 30 minutes. After cooling, the coupon was immersed in deionized water overnight. The coupon was removed from deionized water, tapped dry, and the contact angle with water was measured as described above. The conditions and results for these various coupons are shown in Table 1 below, and measurements were made on uncoated annealed PTFE and uncoated unannealed PTFE for comparison. Based on an analysis of the data therein, it is expected that optimum water-wetting properties will be obtained with a dispersion containing 1 wt% ionomer and a salt solution that is 25 wt% aqueous sodium chloride solution. The second ionomer coating was not observed to have a beneficial effect on the area of minimum contact angle without heat treatment during application. Examples 21-35 The contact angle of the salt solution temperature, the alcohol (ethanol) concentration in the ionomer dispersion, the ionomer concentration in the dispersion, measured on a PTFE coupon coated and annealed as in the above example. A second designed measurement was performed to determine the effect on. A one-layer coating was applied in all cases and the salt concentration was constant in water with 25% by weight sodium chloride. The combinations for these coupons and the contact angle results that test them are shown in Table 2 below. The data in Table 2 show that heating the salt solution to 65 ° C in the indicated method reduces the contact angle and improves the wettability, and further at this temperature the optimum ionomer concentration is It is near 1.5% by weight of the dispersion and suggests that the alcohol concentration in the dispersion should be 63% by volume ethanol in water. Taken together, the above example shows that the coating quality, measured by contact angle, is (under the conditions tested) in dispersions containing 0.5-2.0 wt% ionomer in 40-75 vol% ethanol in water. It is optimal and is shown to be improved by high sodium chloride concentration and high temperature (ie above 65 ° C) in the salt solution used. Examples 36-50 The designed experiments of Examples 21-35 were repeated with unannealed coated PTFE samples and the results are shown in Table 3. Although the contact angle of the unannealed coated PTFE sample was shown to be substantially lower than the corresponding annealed coated PTFE sample, the effects and trends observed in Examples 21-35 are shown in Table 3. But it was observed. Examples 51-56 Polytetrafluoroethylene coupons were coated in these examples with the ionomer dispersion used in the above examples at several different concentrations. The coated coupon is then treated with 5% by weight sodium carbonate (Na ₂ CO ₂ ) Exposed to basic aqueous solution at room temperature (25 ° C). The contact angle was then determined for samples equilibrated or not equilibrated (saturated) by immersion in deionized water prior to contact angle measurement. These data show that the annealed coated PTFE materials generally improve wettability after initial equilibration in water, and with examples of PTFE soaked or treated with the initial sodium chloride solution. Commonly, equilibrated materials starting with ionomer solids concentrations in the coating dispersion above 1 wt% do not result in appreciable improvement. These data also suggest that 5 wt% sodium carbonate solution is preferably used in the coated PTFE materials of these examples, rather than the sodium chloride solution used in the above examples. Examples 57-76 Polytetrafluoroethylene coupons were coated with ionomers from dispersions with varying solids concentrations as in the above examples, at ambient temperature (25 ° C) and several salt solutions of pH 7-12. Soaked in one of them. In these examples, the salt form of the ionomer is Ca in salt solution. ⁺² , Mg ⁺² , Zn ⁺² , K ⁺ , Or Li ⁺ Chloride salt was used to exchange these cations, or a 26 wt% sodium chloride salt solution was used, and then 0.5 M Ca ⁺² , Mg ⁺² , Zn ⁺² , K ⁺ , Or Li ⁺ Was converted to ionomers exchanged with certain of these ions by immersion in a solution of the chloride salt for 1 hour. All samples were rinsed with water and equilibrated prior to contact angle measurements, and both annealed and unannealed samples were prepared and tested. Effect of Ca on the coated PTFE material of the present invention ⁺² Table 5 shows the details of the samples prepared for measuring the effect of E. coli and the results. Mg ⁺² Table 6 lists the samples for the study and their contact angle results. Zn ⁺² , K ⁺ And Li ⁺ Table 7 shows the results of the contact angle wettability test performed on the sample with respect to. These examples show that the salt solution treatment process and the application environment have good flexibility, and, in particular, the calcium and magnesium results show that the presence of these materials in chloralkali environments is such that It is not harmful to the use of coated PTFE in. Example 77 A glass slide was washed by rinsing with acetone and deionized water. The washed glass slides were coated by dipping in 800 equivalents of the ionomer of the above example (again sodium salt) in various concentrations of the dispersion (in 50% ethanol / 50% water). Excess ionomer dispersion was drained from the glass slides, and the glass slides were dipped in 25 wt% NaCl salt solution, rinsed with deionized water, and air dried. The smoothness and coating thickness of the coating thus prepared was analyzed by X-ray photon spectroscopy, where the smoothness was determined by scanning across the coating surface while measuring the atomic% of fluorine in the coating. Was measured. The coating thickness was evaluated by varying the angle of the X-ray photon spectrometer while measuring the silicone signal observed through the coating. The results are shown in Table 8 below. For comparison, the calculated atomic percentage of fluorine in pure anhydrous 800 equivalent ionomer in the form of the sodium salt is 64.4%. Submicron coatings were clearly obtained, and the data suggest that the method of the invention produces coatings with thicknesses close to the dimensions of Langmuir-Blodgett monolayers. The thickness and homogeneity of coatings made by this particular method and containing this particular solvent and ionomer are optimal at any ionomer concentration in the dispersion of 0.5-3.0% by weight. Example 78 A glass slide (19 mm x 75 mm x 1 mm) was used as in Example 77 to determine the% ionomer loading in a film coating made by the method of the present invention from a dispersion of a given concentration of ionomer in alcohol and water. It was washed with acetone and water and preweighed in a clean, clean, wide-mouth jar. These glass slides were then dipped at a constant depth of 60 mm into a dispersion of the same concentration of ionomer as used in Example 77 and the previous examples (thus 24.2 for each glass slide). cm ² To provide a wetted area). The glass slide was removed from the dispersion and allowed to drain for 10 seconds before being contacted with a clean glass slide to remove the last drop of excess dispersion. The wet glass slide was returned to the wide-mouth jar and capped. The jar and the coated glass slides contained therein were reweighed relative to the observed pre-weight to determine the weight of the liquid film of the ionomer solution. The possible coating thickness was calculated in each case, assuming that all ionomers present in the liquid film were deposited as a homogeneous coating on the glass surface. This calculated thickness was compared to the measured thickness of the above example. The results of this test are shown in Table 9. Only a relatively small proportion of ionomer adhered to glass slides from these dispersions. Excess ionomer can be washed off and recovered and reused to form further coatings on various substrates. Example 79 A small piece of platinum foil (1 cm ² Area) grabbed using a pair of tweezers on one side and up to a height of about 2/3 inches in a 1 wt% dispersion of the ionomer in the form of 800 equivalents of sodium perfluorinated sulfonate used in the above example. Soaked in. The foil was then removed and drained for 10 seconds. Drops of water remaining on the bottom of the platinum piece were removed by contacting the foil piece with the rim of the bottle containing the dispersion, and then the wet foil was completely immersed in an aqueous sodium bisulfate solution (20% by weight). . The foil was lightly rinsed with deionized water in the bottle and then immersed in a dilute solution of Safraine O ™ cationic dye. The treated 2/3 inch foil strips absorbed the dye and remained rosy and wet after further rinsing with deionized water. One-third of the untreated (uncoated) foil remained shiny and splashed water into a sphere. Examples 80-89 PTFE coupons were dipped in 1,1,1-trichloroethane and rinsed with acetone and water. They were then dipped into the dispersion of Example 79, removed from the dispersion and temporarily drained and dipped into either a nitric acid solution or an aqueous solution of the salts shown in Table 10 below. The coupons were visually evaluated for surface wettability after rinsing by stirring in a beaker of fresh deionized water. A coupon is considered wettable if the water forms a continuous film on the coupon rather than spheres. The coupons were then dipped in a dilute solution of Safraine O ™ dye and the quality of the coating on this was compared by comparing the color homogeneity (“1” is the most homogeneous color observed. And the higher the number, the lower the homogeneity). The results of these tests are shown in Table 10 below. The color observed on these coupons ranged from deep rosy to very light pink, while the coating with 25 wt% cetyltrimethylammonium chloride was essentially colorless. This color difference is believed to reflect the ease of exchange of the cationic dye in the coating. The sample immersed in nitric acid developed a blue color when dried. For salt solutions, the results in Table 10 suggest that various water-soluble salts may be used in the method of the invention, but the results for high and low concentrations of the surface-active cetyl quaternary ammonium salt are different. It is also suggested that useful water-soluble salts need to be used at different concentrations in order to be effective in forming a satisfactory adherent coating on a given substrate. Examples 90-91 A dispersion of 0.92 wt% ethylene acrylic acid copolymer (containing 20 wt% acrylic acid) was sold as such a polymer (Adoctate 4983 ™ EAA dispersion from Morton International Inc., Acid 1 1 part by weight of a 25% by weight dispersion (containing 25% by weight solids, neutralized with 0.8 equivalents of ammonium hydroxide per equivalent) with 12.8 parts by weight of water and 13.3 parts by weight of ethanol. It was prepared by A PTFE coupon that had been cleaned by washing with acetone, rinsing with deionized water, and drying was dipped in 0.92% dispersion to drain excess and the coated portion with 20% by weight sodium bisulfate. Immersion in an aqueous salt solution followed by a water rinse. The treated part of the coupon was cleanly wet with water. After exposure to Safranine O ™ dye, the treated areas showed very light pink continuous areas. Soak a clean PTFE coupon in a 1.0 wt% solids dispersion (prepared by diluting 1.0 g of Adoctate 4983 ™ material with 23.4 g of deionized water) in water only for comparison. And the excess dispersion was drained. The surface of the coupon, except for a few isolated droplets, was not wet with the dispersion and was immersed in a sodium bisulfate solution, rinsed with deionized water, and diluted in water, but Sfranine O ™. ) Shows only some isolated spots of pink, which roughly correspond to the above dispersion droplets. The procedure with 0.92 wt% solution was repeated for a clean polypropylene cupone. The treated areas of the coupons were again clearly wet with water, and staining with Safranine O ™ dye provided light pink continuous treated areas. Examples 92-93 Samples of sulfonated polystyrene containing 1 milliequivalent of acid per gram of polymer (commercially available, for example, from Aldrich Chemical Co., Inc.) were dissolved in anhydrous dixane to give a 1.1 wt% solution of sulfonated polystyrene. Provided. Acetone was washed, rinsed with water, and the dried PTFE cupone was partially immersed in the sulfonated polystyrene solution and allowed to drain. No continuous film was formed and after immersion in a 20% by weight aqueous sodium bisulfate solution and dyed with Safranin O ™ dye, only isolated areas of the coupon were coated and dyed. Then, a second sulfonated polystyrene solution containing 1.2 wt% sulfonated polystyrene in a mixture of 48 wt% dioxane and 52 wt% water was prepared. Here, the sulfonated polystyrene was first dissolved in dioxane and then diluted with water. A clean PTFE coupon partially immersed in this solution showed a continuous film of the solution on the PTFE coupon. After immersing the wet coupon portion in the same sodium bisulfate solution and rinsing with water, the continuous membrane was wet with water. After staining with Safranine O ™ dye, a continuous rosy area was observed, and some change in shade was also visible. The same procedure also coated polypropylene coupons and produced a translucent continuous water wetted area, which was deep rosy when dyed with Safranine O ™ dye. Example 94-100 CF ₂ = CF ₂ CF ₂ = CFOCF ₂ SO ₂ 800 equivalents of ionomer was prepared by copolymerization with F in an emulsion polymerization system. The resulting polymer was isolated, dried and hydrolyzed with NaOH to provide the ionomer in the form of sodium perfluorinated sulfonate. After washing to neutrality with water, the ionomer is acidified (H ⁺ ) Form. Again, it was washed to neutrality with water, air dried and then charged to a 300 mL stirred Parr bomb reactor with water only. The vessel was closed and heated to temperature with stirring for about 2 hours while monitoring the system pressure. After cooling to ambient temperature, the amount of ionomer in the dispersion (and the yield of ionomer in the dispersion obtained from this) is withdrawn from 25 to 20 g of liquid composition, evaporated to dryness and the residue is weighed. It was decided by. The results are shown in Table 11. Example 101 A 50 gallon (19 liter) container was charged with 292 pounds (133 kg) of water and 9 pounds (4 kg) of the ionomer used in Examples 94-100, the ionomer being converted to its acid form as a powder. . The vessel was closed and heated to 180 ° C-185 ° C for 2 hours with stirring. The pressure was 130 psig (0.9 MPa). After cooling, the amount of polymer in the liquid phase was determined by evaporating a sample of 15-20 g to dryness and weighing the residue. The measured yield was 92%. Example 102 Using the same container, ionomer and procedure as in Example 101, 3 lbs (1.4 kg) of ionomer and 160 lbs (73 kg) of water were loaded into the container. The temperature in this test was 180 ° C. and the measured pressure reached 110 psig (0.8 MPa). The measured yield was 98% under these conditions. Example 103 Approximately 75 lbs (34 kg) of Teflon ™ 7C PTFE powder and 225 lbs (102 kg) of water, Cowles HLM series single shaft mounted high shear melt with 6 inch (15 cm) diameter high shear impeller The PTF E powder was homogeneously pre-sheared in a machine (Morehouse-Cowles Inc., Fullerton, Calif. USA) at a tip speed of 6,600 ft / min (2030 meters / min) for 15 minutes. After removing 65 lbs (29.5 kg) of water, 40 lbs (18 kg) of 2.75 of the above 800 equivalent acid form of the ionomer with stirring at a tip speed of 4,350 ft / min (1340 m / min). A wt% dispersion was added. After stirring for 10 minutes, a homogeneous slurry was obtained. About 21 pounds (9.5 kg) of dry sodium chloride and 4.5 pounds (2 kg) of 50% NaOH were added to the slurry and mixing was continued for another 10 minutes. A homogeneous slurry containing wet ionomer coated PTFE was obtained. Example 104 In this example, 45 g of a short side chain ionomer in the acid form of the type used in Examples 94-100 above, but having 980 equivalent weight, was placed in a vessel with 1400 g of water. The vessel was closed and the water / polymer mixture was heated with stirring to 196 ° C. and 189 psig (1.3 MPa gauge pressure) for 2 hours. After cooling and evaporating a portion to dryness, as in Examples 94-100, the solids content of the dispersion was determined to be 2.82 wt% for a yield of 94-95% (polymer Considering that it was not completely dry when added inside).

────────────────────────────────────────────────── ─── Continuation of front page    (81) Designated countries EP (AT, BE, CH, DE, DK, ES, FR, GB, GR, IE, IT, LU, M C, NL, PT, SE), OA (BF, BJ, CF, CG , CI, CM, GA, GN, ML, MR, NE, SN, TD, TG), AP (KE, MW, SD, SZ, UG), AM, AT, AU, BB, BG, BR, BY, CA, C H, CN, CZ, DE, DK, EE, ES, FI, GB , GE, HU, JP, KE, KG, KR, KZ, LK, LR, LT, LU, LV, MD, MG, MN, MW, M X, NL, NO, NZ, PL, PT, RO, RU, SD , SE, SI, SK, TJ, TT, UA, UZ (72) Inventor Baker, Stan H.             Ray, United States, Texas 77566             Peacock, narcissis strey             To 409 (72) Inventor Davila and Melissa             Ray, United States, Texas 77566             Peacock, garland drive             # 505, 420

Claims (1)

[Claims] 1. A method of coating an ion-containing polymer onto a given substrate, the method comprising: contacting a substrate with a colloidal dispersion or solution of an ion-containing polymer, and thereafter while still wet with the colloidal dispersion or solution. And a solution of the salt or strongly ionizable acid of sufficient concentration to form an adhesive coating of the ion-containing polymer on the substrate without an intermediate drying step and the substrate wetted with the dispersion or solution. And a step of contacting. 2. The method of claim 1 further comprising the step of contacting the coated substrate with a solution containing different cations, thereby producing a form of coated ion-containing polymer exchanged with different cations. 3. Heat treating the coated substrate at an elevated temperature, then contacting the heat treated coated substrate with a colloidal dispersion or solution of an ion-containing polymer, and thus the substrate being wet; A method according to claim 1 or 2 further comprising the step of contacting with a solution of salt or strongly ionizable acid of sufficient concentration to form a second coating of the ion-containing polymer on the substrate. 4. A method according to any one of claims 1 to 3, further comprising the step of annealing the coated substrate at the glass transition temperature of the ionomer or above. 5. The method of claim 4 wherein the substrate is polymeric in nature and the annealing treatment of the coated substrate is carried out at the crystalline melting point of the polymer substrate. 6. Sulfonated polystyrene, copolymers of ethylenically unsaturated carboxylic acid monomers and non-acidic ethylenically unsaturated monomers, or perfluorocarbon ionomers are used in colloidal dispersions or solutions to form coatings on substrates. The method according to any one of claims 1 to 5. 7. Perfluorosulfonic acid ionomer Or Or the alkali metal exchanged salt of any of these perfluorosulfonic acid ionomers. 8. A colloidal dispersion or solution is used to form a coating on a substrate, said dispersion or solution containing no solvent or liquid medium other than water when contacted with the substrate. The method according to any one of 1 to 7. 9. The base material is polytetrafluoroethylene, polyvinylidene fluoride, fluorinated ethylene-propylene copolymer, poly (vinyl chloride), glass, polypropylene, carbon, steel, platinum, chlorotrifluoroethylene or perfluoroalkoxy vinyl ether-tetrafluoroethylene copolymer. The method according to claim 1, which is a fiber, a powder, a cloth or an article. 10. The base material is polytetrafluoroethylene, polyvinylidene fluoride, poly (vinyl chloride), polypropylene, fluorinated ethylene-propylene copolymer, chlorotrifluoroethylene or perfluoroalkoxy vinyl ether-tetrafluoroethylene copolymer, and powder, fiber, or Wherein the step of contacting the substrate with the colloidal dispersion or solution comprises adding the dispersion to the substrate and subjecting the mixture to high shear conditions. The method according to range 8. 11. The solvent-free dispersion has the following formula And formed from a perfluorosulfonic acid ionomer having an equivalent weight of 550 to 1000, the solid content of the ionomer is mixed with the substrate in a weight ratio of 0.015 to 1 or more, and the shearing of the mixture is mixed. 11. The method of claim 10, wherein the blade of the device is at a tip speed of 240 meters / minute or higher. 12. The method of claim 11, wherein the perfluorosulfonic acid ionomer has an equivalent weight of 550-800. 13. The method according to any one of claims 10 to 12, wherein the substrate is polytetrafluoroethylene.