FI83227C - Polymer Blend Membrane - Google Patents

Description

1 83227

Polymeeriseosmembraanit

Semipermeable membranes can be used for a variety of separations such as liquid-liquid separations, liquid-liquid-solid separations, and gas-gas separations. Membranes commonly used for such purposes are, for example, various organic polymers or mixtures of organic polymers, either alone or supported on a porous support material. For example, the semipermeable membranes used in desalination processes may be cellulose acetate polymers deposited on a porous substrate that serves as a membrane support, thin film laminated membranes that are polymerized with a substrate such as polyethyleneimine and polyethylene onene and epylene, polyethylene, polyethylene, polyethylene , etc. The gas separation membranes may be polymeric membranes which are cellulose sanitrate or cellulose acetate, or supported membranes in which the polymer is dimethylsilicone, styrene, silicone carbide copolymer, layered, and thin film polymeric membranes such as polymer membranes. In addition to these membranes, other selectively permeable membranes such as heteropolyacids can be used to separate some gases, such as hydrogen, from gas mixtures in the gas stream.

In most cases, the combination of an organic compound, especially a compound in the form of a polymer, and an inorganic compound results in phase separation because the two systems are immiscible in nature. However, it has now been found that a thin film polymer blend membrane can be prepared by mixing together an inorganic compound such as heteropolyacid or a salt thereof, or phosphoric acid or sulfuric acid with an organic polymer miscible with said inorganic compound to form a polymer-containing material composition which can be used as a membrane. . It was completely unexpected that such a mixture could be cast into a thin film membrane which would be highly selective for some gases and which could therefore be used for such separations as, for example, hydrogen gas separation.

This invention relates to compositions of matter which can be used as gas separation membranes. More specifically, the invention relates to a novel thin film polymer blend membrane for use in gas separation processes.

A conventional method of separating certain gases from a gas stream containing a mixture of gases and in which the desired gas can be separated and recovered involves the use of membranes that are highly permeable to a desired gas such as oxygen, hydrogen, nitrogen, etc. in molecular form. These membranes, especially in the case of hydrogen, have a good permeability to hydrogen and the hydrogen in molecular form is passed from the high pressure side of the device through the membrane as molecular hydrogen to the low pressure side. Alternatively, the separation of the gases can take place by dissociating the desired gas on the high pressure side and transferring it as an ion through the membrane, followed by recombination of the ions on the low pressure side. The membrane required for hydrogen separation should therefore have excellent proton conductivity properties. As will be shown in more detail below, it has now been found that membranes containing both organic and inorganic components have this advantageous property and can therefore be used as hydrogen sensors, hydrogen separation devices as well as a thin film electrolyte in solid form.

It is therefore an object of the present invention to provide novel polymer membranes which can be used in gas separation devices.

It is a further object of this invention to provide a method below

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3,83227 for the preparation of polymer-blended membranes of the type described, which membranes are used in gas separation devices.

An embodiment of the present invention comprises a thin-film polymer-blended membrane characterized in that it is a mixture of an inorganic compound which is a heteropolyacid or a salt thereof, phosphoric acid or sulfuric acid, and an organic polymer miscible with said inorganic compound.

An embodiment of the present invention comprises a process for preparing a thin-film polymer-blended membrane by dissolving an inorganic compound which is a heteropolyacid or a salt thereof, phosphoric acid or sulfuric acid, and an organic polymer miscible with said inorganic compound in a solvent which is miscible with both. , to form a mixture, pouring said mixture onto a casting surface, removing said solvent and recovering the resulting thin film membrane.

A particular embodiment of the present invention comprises a thin film polymer blended membrane consisting of a mixture of poly (vinyl alcohol) and dodecamolybdophosphoric acid, said polymer being present in an amount ranging from about 99% to about 30% by weight of said mixture and said acid being present in an amount ranging from about 1 to about 70% by weight of said mixture.

Another particular embodiment of the present invention is a method of making a thin film polymer blended membrane by dissolving dodecamolybdophosphoric acid and poly (vinyl alcohol) in water at a temperature between ambient temperature and about 100 ° C for a time sufficient to form a mixture. said mixture on the casting surface, removing said water by evaporation and recovering the resulting thin film membrane.

4,83227

Other objects and embodiments will become apparent from the following more detailed description of the present invention.

As stated above, the present invention relates to polymer-blended membranes which are thin films of an organic-inorganic mixture, and to a process for their preparation. As previously mentioned, an attempt to mix an organic polymer and an inorganic compound usually results in phase separation. In contrast, it has now been found that it is possible to obtain a single phase system by mixing certain organic polymeric compounds with inorganic compounds selected from the group consisting of heteropolyacids or their salts, phosphoric acid or sulfuric acid and the resulting composition to form a thin film membrane that can be used in gas separation. . The use of these membranes in gas separation devices is based to some extent on the fact that these inorganic compounds have good proton conductivity, especially at room temperature or at ambient temperature. Membranes formed from a mixture of an organic polymer and an inorganic compound have excellent transport properties as well as stronger tensile strength than those membranes made from organic polymers alone. The physical properties of these thin film membranes therefore mean that it is advantageous to base them on their use as gas sensors, especially in the case of hydrogen, or as gas separation membranes.

As will be shown in more detail below, organic-inorganic mixtures have chemical mechanical and electrical properties that indicate that these two materials form a single phase system. For example, the alloys have only one glass transition temperature, which proves in favor of a single phase in that if the resulting membranes were a two-phase system or a mere physical mixture, it would have two distinct glass transition temperatures. In addition, the strength and modulus of the product are greatly increased by the properties that either of the two components has. Other physical properties that attest to li 5 83227 for a single phase or true composition of matter are that visible light passes through the mixture and is uniform in color.

The membrane in question consists of a mixture of an organic polymer and an inorganic compound, and the inorganic compound is selected from the group consisting of a heteropolyacid or a salt thereof, or phosphoric acid or sulfuric acid, and the polymer is compatible with the inorganic compound. Examples of organic polymers that can be used as one component of the composition of this invention include poly (vinyl alcohol), poly (vinyl fluoride), polyethylene oxide, polyethyleneimine, polyacrylic acid, polyethylene glycol, cellulose acetate, phenyl vinyl ethyl ether, ethyl ethyl methylethyl ether.

Examples of heteropolyacids or their salts which can be used as the second component in the organic-inorganic mixture used to form the membrane are compounds of the general formula VXxYy ° z »'nH2 ° where X is selected from the group consisting of boron, aluminum, gallium , silicon, germanium, tin, phosphorus, arsenic, antimony, bismuth, selenium, tellurium, iodine and metals of the first, second, third and fourth groups of transition metals of the Periodic Table of the Elements, and Y represents other than X and is selected from at least one of the first , a metal of the second, third and fourth groups of transition metals, A is selected from the group consisting of hydrogen, ammonium, sodium, potassium, lithium, rubidium, cesium, beryllium, magnesium, calcium, strontium and barium, m is an integer from about 1 to 10, y is an integer from 6 to 12 based on x = 1, z is an integer from 30 to 80, and n is an integer from 3 to 100.

Specific examples of these compounds include dodekamolybdo phosphoric acid, ammoniummolybdofosfaatti, natriummolybdofosfaatti, 6 83227 kaliummolybdofosfaatti, litiunnrolybdofosfaatti, kalsiumix> lyböofosfaatti, magnesiummolybdofosfaatti, dodekatungstofosforihappo, amino-niumtungstofosfaatti, natriumtungstofosfaatti, kaliumtungsto phosphate, litiumtungstofosfaatti, kalsiumtungstofosfaatti, magnesiumtungstofosfaatti, dodekamolybdopiihappo · ammonium molybdosilikaatti, natriummolybdosilikaatti, kaliummolybdo silicate, litiummolybdosilikaatti, kalsiummolybdosilikaatti, magnesiummolybdosilikaatti, dodekamolybdogermaniumhappo, ammoniummolybdogermanaatti, natriummolybdogerraanaatti, potassium molybdogermanaatti, litiummolybdogermanaatti, kalsiummolybdo-germanates, magnesiummolybdogermanaatti, heksamolybdotelluuri acid, ammoniummolybdotelluraatti, natriummolybdotelluraat-acetate, kaliummolybdotelluraatti, litiummolybdotelluraatti, calcium siummolybdotelluraatti, magnesiummolybdotelluraatti, dodeca -tungstosilicic acid, ammonium tungstosilicate, sodium tungstosilicate, potassium tungstosilicate, lithium tungstosilicate, calcium tungstosilicate, magnesium tungstosilicate, etc.

Within the scope of this invention, it may also be possible to use some uranyl compounds as heteropolyacid or a salt thereof. These uranyl compounds have the general formula: a (uo2) xo4 · n h2o wherein A is selected from the group consisting of hydrogen, lithium, sodium, potassium, ammonium, copper, magnesium, calcium, barium, strontium, lead, iron, cobalt, nickel, manganese and aluminum, X is selected from the group consisting of phosphorus and arsenic and n is an integer from 1 to 4. As specific examples of these uranyyliyhdisteistä are uranyyliortofosfaatti, category nyyliortoarsenaatti, litiumuranyylifosfaatti, litiumuranyyli-arsenate, natriumuranyylifosfaatti, natriumuranyyliarse carbonate, kaliumuranyylifosfaatti, kaliumuranyyliarsenaatti, ammoniumuranyylifosfaatti, ammoniumuranyyliarsenaatti, calcium uranyylifosfaatti, kalsiumuranyyliarsenaatti, bariumuranyyli phosphate, bariumuranyyliarsenaatti, kupariuranyylifosfaatti, kupariuranyyliarsenaatti, rautauranyylifosfaatti, rautauranyy -liarenate, cobalt uranyl phosphate, cobalt uranyl arsenate, nickel uranyl phosphate, nickel uranyl arsenate, etc.

Il 7 83227

The second component of the organic-inorganic mixture is phosphoric acid or sulfuric acid. Examples of phosphoric acids that can be used include hypophosphorous acid, metaphosphoric acid, orthophosphoric acid, pyrophosphoric acid, polyphosphoric acid; or aqueous sulfuric acid, which may be present in about 10 to about 40% sulfuric acid in aqueous solution. It is, of course, clear that the above-mentioned organic polymers and phosphoric acids or sulfuric acid are only representative of the class of components from which the membrane mixture according to the present invention can be prepared, and that said invention is not necessarily limited thereto.

It is also clear that said list of organic polymeric compounds as well as inorganic compounds is only representative of the class of compounds that can be used in the recipes of the organic-inorganic compositions of the present invention, and that the present invention is not necessarily limited thereto.

The novel compositions of matter of the present invention are prepared by mixing both components of the mixture in a solvent in which they both mix under solvent conditions for a time sufficient to form the desired mixture. In a preferred embodiment of the invention, the miscible solvent used to dissolve the components is water, although the scope of the invention is considered suitable for any other miscible solvent, either inorganic or organic in nature. The mixing of the two components of the composition of matter can be carried out under dissolution conditions, i. at a temperature ranging from ambient temperature (20 ° -25 ° C) up to the boiling point of the solvent used, which in the case of water, for example, is 100 ° C. The reaction time required for the formation of the mixture varies depending on the organic polymers and heteropolyacids or their salts used in each case, as well as depending on the solvent, and may take from about 0.5 to about 10 hours or more. After the reaction time, the mixture is cast on a suitable casting surface which may be of any sufficiently uniform material in nature so that the surface is free from defects which could cause unevenness in the surface of the membranes. Examples of suitable casting surfaces are stainless steel, aluminum, etc., glass, polymer or ceramic surfaces. Once the solution is cast on the surface, the solvent is removed by any conventional means such as natural or artificial evaporation using higher temperatures, whereby said solvent evaporates to form the desired membrane, which is a thin film formed by the polymer blend. In a preferred embodiment of the invention, the polymer blend of the organic-inorganic compound has a molecular weight of between about 2,000 to about 135,000 and more preferably greater than 10,000. The film thickness can be controlled by the amount of inorganic compound and / or organic polymer present in the solvent mixture. In this regard, it should be noted that the ratio of inorganic compound to organic polymer can vary within relatively wide limits. For example, the inorganic compound may be present in the mixture at about 1 to 70% by weight of the mixture, while the organic polymer may be present in about 99 to about 30% by weight of the mixture. The thickness of the thin-film organic-inorganic mixture prepared by the process of the present invention may range from about 0.1 to about 50, and is preferably from about 5 to about 20.

The polymer blend membranes of the present invention can be prepared by placing a predetermined amount of each component of the blend, namely the organic polymer and the inorganic compound, in a suitable device such as a bottle. After the addition of the miscible solvent, the mixture is allowed to remain well stirred for the predetermined time shown above. For example, poly (vinyl alcohol) and dodecamolybdophosphoric acid can be bottled and dissolved in water heated to 100 ° C. After the desired residence time, the solution is poured onto a suitable casting surface and the water or other solvent is removed. The resulting polymer blend membrane is then recovered and used in a suitable gas separation device or gas sensor device.

il 9 83227

Examples of new thin film organic-inorganic-of-polymer mixtures, which can be prepared by the method of this invention are poly (vinyl alcohol) -dodekamolybdofosforihappo, poly (vinyl fluoride) -dodekamolyb-dofosforihappo, cellulose asetaattidodekamolybdofosforihappo, polyetyleenioksididodekamolybdofosforihappo, glykolidodekamolybdofosforihappo polyethylene, poly (vinyl alcohol ) -dode-katungstofosforihappo, poly (vinyl fluoride) -dodekatungsto phosphoric acid, cellulose asetaattidodekatungstofosforihappo, polyetyleenioksididodekatungstofosforihappo, glykolidodekatungstofosforihappo polyethylene, poly (vinyl alcohol) -dode-kamolybdopiihappo, poly (vinyl fluoride) -dodekamolybdopii acid, cellulose asetaattidodekamolybdopiihappo, polyethylene nioksididodekamolybdopiihappo , polyethylene glycol dodecamolybdic silicic acid, poly (vinyl alcohol) ammonium molybdophosphate, poly (vinyl fluoride) ammonium molybdophosphate, cellulose acetate ammonium molybdophosphate i polyetyleenioksidiammonium, molybdofosfaatti, polyetyleeniglykoliammoniummolybdofosfaatti, poly (vinyl alcohol) -uranyyliortofosfaatti, poly (vinyl fluoride) -uranyyliortofosfaatti, cellulose asetaattiuranyyli-orthophosphate, polyetyleenioksidiuranyyliortofosfaatti, polyetyleeniglykoliuranyyliortofosfaatti, poly (vinyl alcohol) -ortofosforihappo, poly (vinyl fluoride) -ortofosforihappo, cellulose asetaattiortofosforihappo, polyethylene oxide-orthophosphoric acid, polyetyleeniglykoliortofosforihappo, poly (vinyl alcohol) -pyrofosforihappo, poly (vinyl fluoride) -pyrofosforihappo, asetaattipyrofosforihappo-cellulose, poly-etyleenioksidipyrofosforihappo, polyetyleeniglykolipyrofos-phosphonic acid, poly (vinyl alcohol) -metafosforihappo, poly (vinyl-fluoride) -metafosforihappo, polyetyleenioksidimetafosfo- silicic acid, polyethylene glycol metaphosphoric acid, poly (vinyl alcohol) sulfuric acid, poly (vinyl fluoride) sulfuric acid, cellulose acetate sulfuric acid, polyethylene oxide sulfuric acid, polyethylene lycolic sulfuric acid, etc.

Again, it is clear that the above-mentioned list of polymer blends is only representative of the class of polymer blend membranes that can be prepared by the method 1 ° 83227 of the present invention, and that said invention is not necessarily limited thereto.

As a further technical improvement, it may be advantageous to deposit a polymer blend membrane on a porous substrate to reinforce the structure. When the reaction step referred to above is completed, the mixture is cast on a suitable surface, which in the case of a supported membrane is a porous substrate. The porous support used for structural reinforcement of the membrane contains a compound having a porosity equal to or greater than the porosity of the thin-film inorganic-organic mixture. Within the scope of the invention, it is considered possible to use any relatively open-porous shape or porous substrate having a structural strength greater than that of a thin-film membrane. Examples of these porous substrates are glass cloth, polysulfone, cellulose acetate, polyamides, etc. The amount of mixture to be cast on the porous substrate is such that it is sufficient to form a thin-film membrane of the order of magnitude described above. After casting, a miscible solvent such as water is removed by conventional means such as natural evaporation or artificial evaporation using external heat or vacuum, etc. and the desired membrane, which is a thin-film mixture deposited on a porous substrate, can be recovered and used in a suitable gas separation or gas separation process. .

The reinforced membranes produced according to the method of the present invention have a relatively higher structural strength, which allows the membranes to be manufactured and processed in a more efficient manner. The above membranes can be used either as hydrogen sensors or for gas separation. The device in question can be manufactured by forming a support-structured membrane and then depositing the conductive metal required for the device on both surfaces of the membrane. For example, conductive metal such as platinum, palladium, nickel, copper, etc. can be sprayed onto surfaces in an amount such that the electrode material has a thickness of about 100-1000 A. The membrane containing conductive material on both sides can be placed in a suitable holder and mounted on the electrode and counter electrode. Roll precipitation can be one way of precipitating a conductive material over a membrane and can take place by placing a polymer in a composite membrane! , deposited on a porous substrate, in a spray deposition chamber and by spraying a conductive substance thereon until the desired thickness of said conductive metal is reached. The desired conductive metal can also be deposited on both sides of the membrane by any other means known in the art, such as by impregnation, etc.

The invention therefore also relates to a hydrogen sensor device or a hydrogen separation device having a membrane, metal electrodes on both sides of said membrane and devices for introducing a hydrogen-containing gas onto at least one surface of the membrane, characterized in that the membrane is a thin film polymer blend membrane. is an inorganic compound which is a heteropolyacid or a salt thereof, phosphoric acid and sulfuric acid, and an organic polymer miscible with said inorganic compound.

It may be advantageous to mix the electrically conductive particles into a polymer-containing composition formed by mixing together a heteropolyacid or a salt thereof with an organic polymer compatible with said heteropolyacid or a salt thereof. The electrically conductive particles have the desired properties that allow them to catalyze the dissociation of some gaseous elements, i. the ability to transfer electrons through a particle from one surface to another.

The electrically conductive particles added to the mixture have the ability to catalyze the dissociation of some gaseous elements, mainly hydrogen, although gaseous hydrocarbons such as methane, ethane, propane, etc. may also dissociate when exposed to these particles. In a preferred embodiment of the invention, the electrically conductive particles are Group VIII metals of the Periodic Table of the Elements or alloys of these metals, either with these or other metals. Particularly preferred are metals such as platinum, palladium, ruthenium or nickel or alloys such as platinum-nickel, palladium-nickel, copper-nickel, ruthenium-nickel, etc. The electrically conductive particles may be these metals and either as such in elemental form or the metals may be precipitates on a solid support which itself has electrically conductive properties. An example of this type of electrically conductive support is a solid layered structure having at least a monoatomic layer of a carbonaceous pyropolymer having repeating units containing at least carbon and hydrogen atoms on the surface of the substrate itself, which is a high surface area refractory inorganic oxide. This high surface area refractory inorganic oxide has a surface area of about 1-500 m / g and includes refractory oxides such as alumina in various forms such as gamma alumina, beta alumina, theta alumina or mixtures of inorganic refractory oxides such as silica. alumina, silica-zirconia, zirconia-titanium oxide, zirconia-alumina, zeolites, etc. The form of the inorganic support on which the carbonaceous pyropolymer is precipitated may be any desired and may be prepared by any method known in the art, such as mar by agglo-calibration, etc.

In one method of making a layered structure, the inorganic carrier is heated to a temperature of about 400 ° to about 1200 ° C in a reducing atmosphere containing an organic pyrolyzable compound. Organic pyropolymer starting materials which are most commonly and preferably used include, for example, compounds from the group consisting of aliphatic hydrocarbons such as alkanes, ethane, propane, butane, etc .; alkenes such as ethylene, propylene, isomeric butylenes; alkynes such as ethylene, propyne, 1-butyne, etc .; aliphatic halogen derivatives li 13 85227 such as chloromethane, bromomethane, carbon tetrachloride, chloroform, etc .; aliphatic oxygen derivatives such as methanol, ethanol, propanol, glycol, ethyl ether, formic acid, acetic acid, acetone, formaldehyde, etc., aliphatic sulfur derivatives such as methyl mercaptan, ethyl mercaptan, n-propyl mercaptan, etc .; aliphatic nitrogen derivatives such as nitroethane, nitropropane, acetamide, dimethylamine, etc .; alicyclic compounds such as cyclohexane, cycloheptane, cyclohexene, etc .; aromatic compounds such as benzene, toluene, benzyl chloride, anisole, benzaldehyde, acetophenone, phenone, benzoic acid, etc .; and heterocyclic compounds such as furan, pyran, coumarin, etc. As can be seen, a very wide variety of organic pytolyzable substances are available because almost any organic substance that can be vaporized, decomposed, and polymerized upon heating with refractory oxide is suitable. The resulting carbon-containing pyropolymer has repeating units containing at least carbon and hydrogen atoms; however, depending on the pyropolymer starting material selected, the pyropolymer may also contain other atoms such as nitrogen, oxygen, sulfur or metals such as when an organometallic compound is used as the pyropolymer starting material.

In another embodiment, the layered structure can be prepared by impregnating a refractory inorganic oxide substrate with a solution of a carbohydrate agent such as dextrose, sucrose, fructose, starch, etc., and then drying the impregnated carrier. as described above, forming a carbon-containing pyro-polymer similar in nature to those described above, at least as a monoatomic layer on the surface of a refractory inorganic oxide support.

The support thus formed can then be impregnated with solutions or co-solutions of Group VIII metals of the Periodic Table of the Elements to give the desired electrically conductive particles. Once the desired particle size has been obtained, the degree of roughness of which will be described in more detail below by any method known in the art, such as grinding, dusting, etc., to form the desired particle size, the impregnation can be carried out by treating the carrier with water or water. with an organic solution so that said metal precipitates on the surface of the carbon-containing pyropolymeric support. The solution used to impregnate the carbon-containing pyropolymer is primarily aqueous; examples of these aqueous solutions are chloroplatinum (4) acid, chloroplatinum (2) acid, bromoplatinum (4) acid, platinum (4) chloride, platinum (2) chloride as well as the corresponding solutions of palladium, ruthenium, nickel, etc. Once the structure is impregnated, the solvent can be removed by heating at a temperature in the range of about 100 ° to about 400 ° C depending on the solvent in which the metal compound is dissolved, said temperature being sufficient to evaporate the solvent and leave the metal impregnated on the carbonaceous pyropolymer structure. The structure can then be dried at higher temperatures, from about 100 ° to about 200 ° C for about 2-6 hours or longer.

The metal-impregnated carbonaceous pyropolymer support can then be subjected to a reduction step in a reducing atmosphere or medium such as hydrogen and at elevated temperatures of about 200 ° to about 600 ° C or more for about 0.5 to 4 hours or longer, wherein the metal compound is reduced to the elemental metal state.

The size of the electrically conductive particles to be added to the polymer blend described above is large enough that when forming a thin film membrane of which said particles are an integral part, the surfaces of said particles will be on the surfaces of the thin film blend beyond the surfaces of the polymer blend. part. As discussed above, the thickness of the thin film ireirbran is between about 0.1 and noir. 50 μm and mainly about 5-20 μm. Therefore, the metal or metal-coated particles should have a degree of roughness of about 0.5 to about 55.

The novel thin-film organic-inorganic membrane according to the present invention can be prepared by mixing the two components of the mixture. a heteropolyacid or a salt thereof and a polymeric compound which is at least partially miscible with said acid or salt in a miscible solvent under both dissolution conditions for a time sufficient to form the desired mixture. In a preferred embodiment of the invention, the miscible solvent used to dissolve the components is water, although it is considered within the scope of the invention to use any other miscible solvent, whether organic or inorganic in nature.

The mixing of the two components of the mixture can be carried out under dissolution conditions at a temperature between ambient temperature (20 ° -25 ° C) and the boiling point of the solvent miscible in both, for example 100 ° C in the case of water. The electrically conductive particles are added to the solution and the solution is mixed very thoroughly by any means such as mixing, shaking, rotating, etc. In a preferred embodiment of the invention, any type of dispersant well known in the art may also be added to the solution to ensure that the particles do not clump or agglomerate. evenly into solution. The reaction time required to form the desired mixture varies depending on the organic polymer and heteropolyacid or their salts used, as well as the solvent, and may range from about 0.5 hours to about 10 hours or more. After the reaction time has elapsed, the mixture can be poured onto a suitable casting surface, which can be any suitable material having the desired properties so as to provide a flawless surface and not cause unevenness to the membrane surfaces. Examples of suitable casting surfaces that can be used are metals such as stainless steel, aluminum, etc., glass, ceramics or polymers. Once the solution is poured on the surface, the solvent can then be removed by any conventional means such as natural evaporation or artificial evaporation by applying higher temperatures to the casting surface, said solvent evaporating to form the desired thin film membrane, a polymer blend containing uniformly dispersed electrically conductive electrically.

i6 83227

Alternatively, the membrane can also be reconstituted by precipitating the solution from a non-solubilizing agent. Examples of the non-solvent to be used include lower alcohols such as methanol, ethanol, propanol, etc .; paraffin-hydrocarbons such as pentane, hexane, heptane, etc .; chlorinated hydrocarbons such as chloroform, bromoform, carbon tetrachloride, dichlorobenzene, methylene chloride, etc .; ketones such as acetone, methyl ethyl ketone, methyl propyl ketone, etc .; carboxylic acids such as formic acid, acetic acid, propionic acid, trichloroacetic acid, etc .; esters such as methyl acetate, ethyl acetate, methyl acrylate, methyl methacrylate, etc .; tetrahydrofuran, etc .; as well as concentrated saline solutions. It will be appreciated, of course, that the non-solvent used in each case depends on the polymer used and the heteropolyacid or salt thereof which is mixed together to form the desired inorganic-organic polymer blend.

As an alternative method of preparing the membrane of the invention, the heteropolyacid or a salt thereof and the organic polymer may be mixed with each other in a manner similar to that described above under dissolution conditions and allowed to react long enough to form the desired mixture. The mixture can then be poured onto a suitable casting surface and electrically conductive particles can then be added to the mixture over the casting surface so as to ensure an even and uniform distribution of the particles throughout the mixture. The solvent is then allowed to evaporate and the resulting membrane is recovered. The solvent can also be removed by reprecipitating the solution in a non-solvent of the type described above.

As a specific example of the preparation of the membranes according to the present invention, a predetermined amount of each component of the mixture, namely the organic polymer and the heteropolyacid or its salt, can be placed in a suitable device such as a bottle. Once the miscible solvent has been heated and the components of the mixture have dissolved, electricity can be added

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i7 83227 conductive material particles of the type described above, and after mixing very efficiently, the mixture is allowed to stand long enough for the mixture to form and then cast on a suitable casting surface. As an even more specific example, poly (vinyl alcohol) and dodeca-molybdophosphonic acid can be placed in a flask and dissolved in water heated to 100 ° C. Particles of an electrically conductive material such as platinum deposited on the surface of a solid support consisting of at least one monoatomic layer of a carbon-containing pyropolymer having repeating units containing at least carbon and hydrogen atoms on the surface of the substrate itself, refractory can then be added. inorganic oxide having a surface area, and the solution is mixed thoroughly by shaking. After standing for the desired time, the solution is poured onto a suitable casting surface, such as glass, and the water is removed. The resulting polymer blend membrane, which contains electrically conductive particles that form part of the membrane and whose surfaces are present on or extend over the surfaces of the polymer, is recovered and used in any suitable gas separation device or gas sensor device.

Membranes consisting of a mixture of a hetero-polyacid or a salt thereof and an organic polymer containing electrically conductive particles whose surfaces are present on or extend over the surfaces of the mixture can be used as a flat surface or in the form of a tube. Tubes consisting of a polymer blend with electrically conductive particles can be made by pushing the mixture through a compression mold, ensuring that the core of the tube is hollow. When this type of construction is desired, electrically conductive particles can be added to the solution before the tube is formed, with one surface of each particle facing inwardly of the tube and the other surface of the particle being on or extending beyond the outer surface of the tube. The size of the formed tube can vary relatively widely and the thickness of the walls of the tube depends on the mode of use.

18 83227

The following examples are provided for the purpose of illuminating the novel membranes of the present invention. It must be borne in mind, however, that these examples are merely illustrative in nature and that the method in question is not necessarily limited to them.

Example I

A new polymer blend membrane was prepared by dissolving poly (vinyl alcohol) and dodecamolybdophosphoric acid in boiling deionized water, and the amounts of organic polymer and heteropolyacid were such that the resulting polymer blend membrane had a weight ratio of 50/50. The solution was then poured into an evaporation vessel and the water was allowed to evaporate for 16 h. The resulting blend film was yellow-green in color and had a thickness of 20.

The thin film membrane was cut into a round plate with a diameter of 2.5 cm and the electrodes were syringe dispersed on both sides of the plate. The electrode material was platinum and had a thickness of about 10 ° C to about 200 Å and a diameter of about 1.2 cm. The film was then placed in a Teflon holder and an electrical contact was installed on the electrodes through copper plates. On the other side of the membranes, a hydrogen pressure of 1 atmosphere was maintained and hydrogen was introduced into the working electrode containing a sufficient amount of water in the form of water vapor so that the relative humidity was maintained at at least 30% with a hydrogen partial pressure of 0.02 atmospheres. The result of this experiment showed a hydrogen flow of 445 x 10 m / m * h and an electric current of 1.337 x 10 mA.

In addition, several analyzes were performed on the film to determine if the film was single-phase or two-phase. The blend film was found to be optically transparent, and no phase separation was observed when the film was viewed with an optical or scanning electron microscope (SEM). The glass was also subjected to a glass transition temperature measurement, as the glass transition temperature or the temperature of the polymer blend 83227 space measurement is the most commonly used criterion for deciding the number of phases in a blend. For example, a single-phase organic-inorganic mixture has a single glass transition temperature between component temperatures, while a two-phase system has two separate temperatures. Poly (vinyl alcohol) has a known glass transition temperature, about 71 ° C, while dodecamolybdophosphoric acid has a melting point of about 84 ° C. The DSC-Calorimeter study of the film prepared according to the above sections had a peak at 78 ° C, but no peaks were observed at temperatures corresponding to the glass transition temperatures of poly (vinyl alcohol) or the melting point of dodecamolybdophosphoric acid.

Infrared spectroscopy of the film showed strong streaks at 820 cm-1, 885 cm-*, 972 cm-1 and 1075 cm-1. This analysis proves that the bands are related to the intramolecular bond between poly (vinyl alcohol) and dodecamolybdophosphoric acid. In addition to these analyzes, it was found that the alloy film has a higher tensile strength and modulus than both poly (vinyl alcohol) and dodecamolybdophosphoric acid, and the increase in tensile strength and modulus may be the result of a stronger hydrogen bond due to single phase formation.

Example II

Still other organic polymer-heteropoly acid blend membranes were prepared using a method similar to that described in Example I above. Membranes were prepared using different poly (vinyl alcohol) (PVA) / dodecamolybdophosphoric acid (DMPA) batches. The prepared films contained 90% PVA / 10% DMPA, 75% PVA / 25% DMPA and 40% PVA / 60% DMPA in batches and were marked with the letters A, B and C, respectively. Each film was about 20 μm thick and, after recovery, was cut into 2.5 cm diameter plates. The platinum electrodes were spray dispersed on both sides of the plate into layers about 100 Å thick. The electrode membrane layers were then used in a manner similar to that shown in Example 8 above in a gas separator at a hydrogen partial pressure of 0.02 atmospheres obtained by stirring hydrogen containing sufficient water in the form of water vapor to maintain a relative humidity of at least 30%. as a percentage, and either helium or nitrogen. Hydrogen flow through the mixture membranes occurred at room temperature and the results were as follows; I (mA) means electric current: 3 2

Membrane I (mA) Flow rate (m / m xh) A 5 x 10 "4 1.71 x 10 ~ 6 B 3.1 x 10-2 103.3 x 10-6 C 1.337 x 10'1 445 x 10 ~ 6

Example III

In a similar manner to that described in Example I above, other organic-inorganic membranes were prepared by mixing poly (vinyl alcohol) with dodecamolybdophosphoric acid, cellulose acetate with dodecamolybdophosphoric acid, poly (vinyl alcohol) with uranyl orthophosphate, and poly (vinyl). The resulting membranes were then treated by spray precipitation of platinum or palladium on both sides of said membrane to a thickness of about 100 to about 200 Å, and the resulting layer was used in a gas separator to separate hydrogen from a gas stream containing hydrogen and other inert gases such as helium or nitrogen.

Example IV

A thin film membrane containing a polymer blend of the present invention was prepared by dissolving 0.25 g of poly (vinyl alcohol) and 0.1 ml of 18 M orthophosphoric acid in boiling deionized water, and the amount of poly (vinyl alcohol) and orthophosphoric acid was sufficient to provide the resulting polymer blend membrane. weight ratio 60/40% by weight.

The solution was then poured into an evaporation vessel and the water was allowed to evaporate for 18 h. The obtained film was transparent and had a thickness of 20 μm. The thin film membrane was cut into a round plate with a diameter of 2.5 cm and platinum electrodes were spray-deposited on both sides of the plate 21,83227. The thickness of the electrode material is between about 200-1000 Å and the diameter is about 1 cm. The membrane was then placed in a Teflon holder and electrical contact with the electrodes was installed through the copper plates. On the other side of the membrane, a hydrogen pressure of 1 atmosphere was maintained and a stream of hydrogen was applied to the drive electrode. The results of this test showed a hydrogen flow of about 16.4-10 cm and a current density in milliamperes of about 3 x 10 ® A / cm 2.

Furthermore, membrane analyzes showed that the membrane was single-phase and not biphasic. The mixed film was found to be optically transparent, and no phase separation was observed when the film was examined with an optical microscope or a scanning electron microscope (SEM). The glass transition temperature was also measured for the substance, because measuring the glass transition temperature or measuring polymer temperatures is the most commonly used criterion for determining the number of phases in a mixture. For example, a single-phase organic-inorganic mixture has a single glass transition temperature between component temperatures, while a two-phase system has two separate temperatures. Poly (vinyl alcohol) has a known glass transition temperature of about 71 ° C, while orthophosphoric acid has a boiling point of 213 ° C. The DSC calorimetric test of the film prepared according to the above points had a peak at about 75 ° C, but no peaks were observed at temperatures corresponding to the glass transition temperature of poly (vinyl alcohol) and the boiling point of orthophosphoric acid.

Infrared spectroscopy of the film showed strong streaks at 2400 cm -1, 1020 cm -1, 700 cm -1 and 500 cm -1.

This analysis indicates that the bands are related to the intramolecular bond between poly (vinyl alcohol) and orthophosphoric acid. In addition to these analyzes, it was found that the alloy film had increased tensile strength and modulus compared to both poly (vinyl alcohol) and orthophosphoric acid, and the increase in tensile strength and modulus may be due to stronger hydrogen bonding during the formation of the single phase material.

Example V

An organic polymer-phosphoric acid blend membrane was prepared in the same manner as described above. The film membrane containing a 60/40% by weight mixture of poly (vinyl alcohol) and orthophosphoric acid was about 20 μm thick and was cut into a 2.5 cm diameter round plate. Platinum electrodes were spray dispersed on both sides of the plate to a thickness of 400 Å. The membrane was then placed in a similar Teflon cell in the center of the cell so that both sides of the cell became airtight. A reference gas of 100% hydrogen and a treatment gas of 9.987% hydrogen and 90.013% nitrogen were placed on each side of the cell. The gases were continuously passed through the cell and a 29.4 millivolt output EMF was generated. When there is pure hydrogen on both sides of the membrane, the output EMF is 0 millivolts compared to this. The membrane resistance was about 104.

Example VI

Similar polymer blend membranes can be prepared by mixing other organic polymers such as cellulose acetate or poly (vinyl alcohol) and sulfuric acid to give the desired thin film polymer blend membranes similar to those described in Examples IV and V above and having similar properties.

Example VII

A polymer blend membrane was prepared by dissolving poly (vinyl alcohol) and uranyl orthophosphate in boiling deposited water, and the amounts of organic polymer and heteropolyacid salt were sufficient to provide a 50/50 weight percent ratio to the resulting polymer blend. The solution was filtered and poured onto a fine glass cloth placed in a standard Petri dish. The water was allowed to evaporate for 48 h, resulting in a layered membrane consisting of a thin-film membrane deposited on a porous substrate.

23 83227

Example VIII

In the same manner as described above, a polymer blend was prepared by dissolving poly (vinyl alcohol) and dodecamolybdophosphoric acid in deionized water at 100 ° C. The resulting solution was then poured onto the surface of the porous substrate, which was polysulfone, in a sufficient amount so that, after evaporation of the water, the thickness of the polymer blend membrane was about 50. The layered membrane consisted of a polymer blend on top of a polysulfone and was recovered and used in a hydrogen sensor device.

Example IX

In this example, a polymer blended membrane was prepared by dissolving dodecamolybdophosphoric acid and cellulose acetate in boiling water and the amounts of said polymer and acid were sufficient so that the final polymer blend contained 50/50% by weight relative to the two components.

The solution was then poured onto the surface of the glass cloth and, after allowing the water to evaporate, the layered membrane was recovered.

A layered, structurally stronger membrane can be prepared by dissolving equimolar amounts of dodecatungstophosphoric acid and poly (vinyl alcohol) in boiling deionized water, followed by thorough mixing. The resulting solution is then poured onto a porous substrate of polysulfone, and when the water has evaporated, the resulting layered membrane is recovered.

Example X

To illuminate the gas sensing properties of the layered membranes of this invention, a polymer blend membrane was prepared according to the procedure described in Example VIII by dissolving poly (vinyl alcohol) and uranyl orthophosphate in boiling deionized water and pouring the filtered solution into a fine glass cloth. the ratio of these two components and its total thickness of 75 μm. The sensor was fabricated by cutting a 24 8 3 2 2 7 supported membrane into a circle 2.5 cm in diameter and spray depositing 1.27 cm diameter platinum electrodes on each side of the membrane. The membrane was then placed in a round Teflon cell and the sensor was mounted in the center of the cell so that both sides of said cell became airtight. A reference gas of 100% hydrogen and a treated gas of 9.995% hydrogen and 91.005% nitrogen were placed on different sides of the cell. The gases were continuously driven through the cell and the sensor gave a voltage of 29.4-29.5 millivolts. The calculated voltage at 23 ° C is 29.4 millivolts. When there is pure hydrogen on both sides of the sensor, the voltage compared to this is 0 millivolts.

A similar layered membrane was prepared by dissolving poly (vinyl alcohol) and dodecamolybdophosphate in boiling deionized water.

After filtration, the solution was poured onto a fine glass cloth and the sensor was prepared in a similar manner to that shown in the example above. The sensor was used in a cell similar to that described above and the voltage was found to be 29.4-29.5 millivolts, and the voltage obtained by calculating at 23 ° C would be 29.4 millivolts.

Example XI

To demonstrate the higher structural strength of the layered polymer blend membrane of the present invention, a polymer blend membrane containing 50/50 wt% dodecamolybdophosphoric acid and poly (vinyl alcohol) having a molecular weight of 16,000 was cast on a fine glass cloth and the solvent was removed. Another similar membrane was also made, but it was not cast on a fabric substrate. A rupture tester was prepared by placing a layered membrane on a metal plate with a square hole 2.5 cm in diameter in the center, and said membrane was held at the bottom by means of a seal and the metal plate was provided with a hole for gas inlet. Air was forced through the membrane at various pressures for predetermined lengths of time to determine the amount of pressure required to rupture the membrane. The membrane supported on the glass cloth was labeled A and the unsupported membrane was labeled B. The results of the rupture test are shown in Table 1 below:

table 1

A B

2.3 kg for 1 min 2.3 kg for 1 min 4.5 kg for 1 min 4.5 kg for 1 min 6.8 kg for 1 min 6.8 kg for 1 min 9.1 kg for 1 min 9.1 kg for 1 min 11.3 kg 1 min for 11.3 kg 1 min for 13.6 kg 1 min for 13.6 kg for 1 min - fracture 15.9 kg 1 min for Mon syn- 18.1 kg 1 min for work 20.4 kg 1 min for hole 22.7 kg for 1 min in the middle 24.9 kg for 1 min - a fracture occurred along the sides of the hole

A similar layered membrane was prepared with a weight ratio of 50/50% by weight between uranyl orthophosphate and poly (vinyl alcohol) having a molecular weight of 16,000. Layered membrane C was from this mixture and supported on a glass cloth, while membrane D was unsupported. The membranes were subjected to a rupture test in a device similar to that previously described and the results of said test are shown in the following Table 2:

Table 2

C D

2.3 kg for 1 min for 2.3 kg for 1 min for 4.5 kg for 1 min for 4.5 kg for 1 min for 6.8 kg for 1 min for 6.8 kg for 1 min - deformed 9.1 kg for 1 min for 9.1 kg for 1 min for 11.3 kg for 1 min for 11.3 kg for 1 min - a fracture of 13.6 kg for 1 min occurred in 15.9 kg for 1 min in the middle of the hole 18.1 kg for 1 min at 20.4 kg for 1 min - a fracture occurred along the sides of the hole

From the results shown in the above tables, it can be easily seen that the polymer blend membrane cast on the substrate has a higher structural strength than the unsupported 26 8 3 2 2 7 membrane, which is manifested by a higher amount of pressure required to break the membrane.

Example XII

A polymer blend membrane was prepared by dissolving 0.5 g of poly (vinyl alcohol), molecular weight 16,000, and 0.2 ml of orthophosphoric acid in boiling deionized water, and the amounts of organic polymer and acid were such that the resulting polymer blend had a weight ratio of 60/40% by weight. . After sufficient time for the polymer mixture to form, the solution was mixed and poured onto a fine glass cloth standard on a Petri dish. The water was allowed to evaporate for 48 h to give a layered membrane with a thin-film membrane deposited on a glass cloth and a thickness of 95.

Example XIII

In a similar manner, a polymer blend membrane was prepared by dissolving 0.17 cm of sulfuric acid and 0.5 g of poly (vinyl alcohol) having a molecular weight of 16,000 in boiling deionized water. After some time, the solution was poured onto a fine glass cloth placed in a standard Petri dish. The water was allowed to evaporate for 48 h and the resulting layered membrane was recovered.

Example XIV

In the same manner as above, an inorganic-organic-polymer mixture was prepared by dissolving poly (vinyl alcohol) and pyrophosphoric acid in boiling deionized water, and the amounts of polymer and acid are such that a weight ratio of 60/40% by weight is obtained. The solution can then be poured onto a porous surface of polysulfone in such an amount that, after evaporation of the water, the thickness of the polymer blend membrane is about 50. Once the water has evaporated, the layered membrane formed from the polymer blend on top of the polysulfone can be recovered.

27 83227

Example XV

In this example, a polymer blend membrane is prepared by dissolving cellulose acetate and potassium phosphate in boiling deionized water, and after sufficient time for the mixture to form, the solution can be poured onto a glass cloth. After allowing the water to evaporate for 48 h, a layered membrane is obtained.

Similarly, yet another polymer blend membrane can be prepared by dissolving poly (vinyl alcohol) having a molecular weight of 16,000 and ammonium phosphate in boiling deionized water. After thorough mixing, the solution is allowed to stand for some time so that a polymer blend is formed. The polymer mixture can then be poured onto a porous substrate of polysulfone, and when the water has evaporated, which takes 48 hours, the resulting layered membrane is obtained.

Example XVI

To illuminate the gas sensing capability of the layered membranes of the present invention, a sensor was prepared from a polymer blend membrane according to the method set forth in Example XII above. The sensor was prepared by cutting the supported membrane into a round plate with a diameter of 27.9 cm and spray dispersing platinum electrodes with a diameter of 1.27 cm on each side of the membrane. The membrane was then placed in a circular Teflon cell and said sensor was placed in the center of said cell so that both sides of said cell were made airtight. A reference gas consisting of 100% hydrogen and a treat gas consisting of 91.013% nitrogen and 9.987% hydrogen was placed on each side of the cell. The gases were made to flow continuously through the cell and the sensor gave a voltage of 0 millivolts when there was hydrogen on both sides of the sensor and up to a voltage of 29.6 millivolts when the reference gas and the gas to be treated were present. The latter voltage is comparable to the calculated voltage of 29.6 millivolts at o 5 25.3 C. In addition, it was found that the resistance was 0.375 x 10 ohms.

The membrane prepared according to the method of Example II was tested in the same manner and the sensor was found to give 28 83227 a voltage similar to that of a membrane which was a mixture of poly (vinyl alcohol) and orthophosphoric acid and had a somewhat higher resistance.

Example XVII

To illuminate the higher structural strength of the polymer blend deposited on a porous solid support, which was an example of the blends of the present invention, compared to unsupported membranes, two polymer blend membranes were prepared. The polymer blend was prepared by dissolving 0.5 g of poly (vinyl alcohol) having a molecular weight of 16,000 and 0.2 ml of orthophosphoric acid in boiling deposited water. The resulting mixture was poured onto a glass cloth having a thickness of 30. The second mixture was prepared by mixing equal portions of poly (vinyl alcohol) and orthophosphoric acid and pouring the resulting mixture onto a Petri dish without a support. After removal of the solvent, both membranes were recovered.

A rupture tester was prepared by placing a layered membrane on a metal plate with a 2.54 cm diameter square hole in the center thereof, and said membrane was held in place by a seal and the metal plate was provided with an opening for gas inlet. Air was pushed through the membrane at various pressures for a predetermined time to measure the amount of pressure required to rupture the membrane. The membrane supported on the glass was labeled A and the unsupported membrane was labeled B. The results of the burglary test are shown in Table 3 below:

Table 3

A B

4.5 kg / 1 min 2.3 kg less than 6.8 kg / 1 min per minute - the middle part stretched 9.1 kg / 1 min until it broke in the middle, 3 kg / 1 min cook 13.6 kg / 1 min 15.9 kg / 1 min - crack at the edges of the hole li 29 8 3 2 2 7 In addition, another sample of unsupported membrane was placed in the holder and 0.14 kg / cm of air was allowed to pass over the membrane.

The film stretched towards the hole by about 9 mm and lasted. When the air pressure was stopped, the membrane was removed and it was found that a permanent deformation had occurred.

The results shown in the table above show that the polymer blend membrane cast on the porous substrate had a higher structural strength than the unsupported membrane.

Example XVIII

A new polymer blend membrane was prepared by placing 0.25 g of poly (vinyl alcohol) and 0.25 g of dodecamolybdophosphoric acid in a flask, 20 ml of deionized water was then placed in a flask heated to a sufficiently high temperature to dissolve both the polymer and the acid. After a sufficient time after the mixture had formed, the solution was poured into a Petri dish and cobalt particles were added, and the amount of particles added was sufficient so that the particles were evenly distributed throughout the membrane. The water was allowed to evaporate for 16 h and the resulting film having a thickness of 20 was removed. In order to obtain a membrane in which the electrically conductive particles have the ability to form protons, platinum was sprayed on the surface of the membrane using a conventional spraying technique, and spraying took place on both sides of the membrane.

Example XIX

In this example, a membrane was prepared using the technique described in Example XVIII above, i.e. 0.25 g of poly (vinyl alcohol) and 0.25 g of dodecamolybdophosphoric acid were placed in a flask and 20 ml of deionized water was added. The flask was heated to a temperature high enough to dissolve the polymer and acid, and the resulting solution was then poured onto a casting surface which was a Petri dish. Then, electrically conductive particles platinum deposited on a solid support consisting of at least 30,83227 single monatomic layers having a carbon-containing pyropolymeric structure with repeating units containing at least carbon and hydrogen atoms on a large surface area were added to the solution. on the surface of an alumina substrate having a region; the addition took place in such a way that the particles were evenly distributed throughout the polymer mixture. After the water had evaporated, the resulting membrane was peeled from the vessel and recovered.

Example XX

As described above, equimolar amounts of uranyl orthophosphate and poly (vinyl alcohol) were placed in a flask, then deionized water was added and the flask was heated until both the heteropolyacid salt and the polymer were dissolved. Nickel particles are then added to the solution, which is then mixed very well to ensure that the nickel particles are evenly distributed throughout said solution. The resulting mixture is then poured onto a casting surface and the solvent, which is water, is allowed to evaporate. After evaporation of the water, the obtained thin film membrane is recovered.

Example XXI

A thin film membrane can be prepared by combining equimolar amounts of dodecamolybdophosphoric acid and cellulose acetate in a solvent of deionized water and the temperature of the water high enough for the acid and polymer to dissolve therein. The resulting solution can then be poured onto a casting surface of the type described above and particles of electrically conductive material such as elemental ruthenium can then be uniformly dispersed throughout the solution. The water can be evaporated for 16 h, after which the resulting film is recovered.

li

Claims (24)

3i 83227 A thin-film polymer blend membrane, characterized in that it is a blend of an inorganic compound which is a heteropolyacid or a salt thereof, phosphoric acid or sulfuric acid, and an organic polymer miscible with said inorganic compound. A membrane according to claim 1, characterized in that when said inorganic compound is a heteropolyacid or a salt thereof, said mixture contains a large amount of electrically conductive particles forming a part of said membrane and the particle size is sufficiently large so that the surfaces of said particles are at or extending beyond the surfaces of the membrane. Membrane according to Claim 1, characterized in that it is deposited on a porous substrate in order to obtain greater structural strength. Membrane according to claim 1, characterized in that said membrane has a thickness of about 0.1 to 50 μm. The membrane of claim 1, characterized in that said inorganic compound is present in said mixture in an amount of about 1-70% by weight of said mixture and said organic polymer is present in said mixture in an amount of about 99-30% by weight of said mixture. . Membrane according to claim 3, characterized in that said porous substrate is a glass cloth or a polysulfone. Membrane according to claim 2, characterized in that said electrically conductive particles have the ability to form a proton. 32 83227 Membrane according to Claim 7, characterized in that the electrically conductive particles are a metal of Group VIII of the Periodic Table of the Elements or an alloy thereof. Membrane according to claim 8, characterized in that said Group VIII metal of the Periodic Table of the Elements or an alloy thereof is doped on a solid support. A membrane according to claim 9, characterized in that said solid support consists of at least one monoatomic layer of a carbon-containing pyropolymer having repeating units containing at least carbon and hydrogen atoms deposited on the surface of a high surface area refractory inorganic metal oxide. Membrane according to claim 8, characterized in that said metal of Group VIII of the Periodic Table of the Elements or an alloy thereof is platinum, palladium or an alloy of platinum and nickel. Membrane according to claim 1, characterized in that the general formula of said heteropolyacids and salts of heteropolyacids is: Am <Vy ° z> · nH 2 O wherein X is boron, aluminum, gallium, silicon, germanium, tin, phosphorus, arsenic, antimony , bismuth, selenium, tellurium, iodine or a metal of the first, second, third and fourth series of transition metals of the Periodic Table of the Elements, and Y is different from X and at least one metal of the first, second, third and fourth series of transition metals of the Periodic Table of the Elements, A is hydrogen, ammonium, sodium, potassium, lithium, rubidium, cesium, beryllium, magnesium, calcium, strontium or barium, and m is an integer of about 1-10, y is an integer of 6-12, which is basic; 33 8 3 2 2 7 that x «1, z is an integer from 30 to 80 and n is an integer from 3 to 100. 13. A method for producing a thin-film polymer blend membrane, characterized by dissolving an inorganic compound which is a heteropolyacid or a salt thereof, phosphoric acid or sulfuric acid, and an organic polymer miscible with said inorganic compound in a solvent miscible with both. in sufficient proportions to form a mixture, pouring said mixture onto a casting surface, removing said solvent, and recovering the resulting thin film membrane. A method according to claim 13, characterized in that when said heterologous acid or a salt thereof is selected as said inorganic compound, the method further comprises adding electrically conductive particles to said solution, mixing said solution and said particles, casting a mixture containing said particles on a casting surface, removing said solvent and recovering the resulting membrane. A method according to claim 14, characterized in that said solution contains a dispersing agent. A method according to claim 13, characterized in that said mixture is cast on the surface of a porous substrate, said solvent is removed and the resulting thin-film polymer blend membrane with added structural support is recovered. A method according to claim 13, characterized in that said dissolution conditions comprise a temperature range from room temperature to about 100 ° C. A method according to claim 13, characterized in that said solvent which is miscible with both is water. 34 83227 Process according to Claim 18, characterized in that the water is removed by evaporation. A method according to claim 14, characterized in that said solvent is removed by reprecipitation from a non-soluble substance. A hydrogen sensor or hydrogen separation device comprising a membrane, metal electrodes on both sides of said membrane and devices for supplying a hydrogen-containing gas to at least one surface of the membrane, characterized in that the membrane is a thin-film polymer blend membrane which is a mixture of an inorganic compound -acid acid or a salt thereof, phosphoric acid or sulfuric acid, and an organic polymer miscible with said inorganic compound. Device according to claim 21, characterized in that when said inorganic compound is a heteropolyacid or a salt thereof, said mixture contains a large amount of electrically conductive particles forming part of said membrane and the particle size is sufficiently large so that the surfaces of said particles are on or extending beyond the surfaces of said membrane. Device according to claim 21, characterized in that said membrane is deposited on a porous substrate in order to obtain a higher structural strength. Membrane according to claim 1, characterized in that said organic polymer is poly (vinyl alcohol), poly (vinyl fluoride), polyethylene oxide, polyethyleneimine, polyacrylic acid, polyethylene glycol, cellulose acetate, polyvinylmethylethyl ether or phenol formaldehyde. 35 8 3 2 2 7