103results about How to "Low methanol permeability" patented technology

Novel multiblock copolymers containing perfluorinated poly(arylene ether) as a hydrophobic segment and disulfonated poly(arylene ether sulfone) as a hydrophilic segment are provided. The multiblock copolymers are used to form proton exchange membranes that are thermally and hydrolytically stable, flexible, and that exhibit low methanol permeability and high proton conductivity. The proton exchange membranes are thus well-suited for use for use as polymer electrolytes in fuel cells.

A proton exchange polymer membrane whose surface is treated by direct fluorination using a fluorine gas, a membrane-electrode assembly, and a fuel cell comprising the same are provided. The proton exchange polymer membrane of the present invention exhibits improved proton conductivity, high dimensional stability, and decreased methanol permeability through introducing hydrophobic fluorine having high electronegativity to the surface of the polymer membrane. Therefore, the proton exchange polymer membrane with excellent electrochemical properties of the present invention can be preferably utilized as polymer electrolyte membrane for fuel cell, generating electric energy from chemical energy of fuels.

The invention provides a crosslinkable aromatic resin having a protonic acid group and a crosslinkable group, suitable for electrolytic membranes and binders used in fuel cells, etc., and electrolytic polymer membranes, binders and fuel cells using the resin. The crosslinkable aromatic resin has a crosslinkable group, which is not derived from the protonic acid group and can form a polymer network without any elimination component. This resin exhibits excellent ion conductivity, heat resistance, water resistance, adhesion property and low methanol permeability. Preferably, the crosslinkable group is composed of a C₁ to C₁₀ alkyl group directly bonded to the aromatic ring and/or an alkylene group having 1 to 3 carbon atoms in the main chain in which at least one carbon atom directly bonded to the aromatic ring bonds to hydrogen, and a carbonyl group, or a carbon-carbon double bond or triple bond. The aromatic resins such as aromatic polyethers, aromatic polyamides, aromatic polyimides, aromatic polyamideimides, aromatic polyazoles, etc., which contain such a crosslinkable group, are preferred as the crosslinkable aromatic resins having a protonic acid group and a crosslinkable group.

A high-performance solid polyelectrolyte film is provided which is produced by the radiation-induced graft polymerization method without causing solution gelation and which is excellent in mechanical strength, chemical stability, and dimensional stability and reduced in methanol permeability. According to the present invention, the solid polyelectrolyte film is produced by graft-polymerizing either a polymerizable monomer having an alkoxysilyl group alone or the polymerizable monomer having an alkoxysilyl group and another polymerizable monomer with a resin film which has been irradiated with a radiation, followed by hydrolyzing the alkoxysilyl groups to conduct dehydrating condensation. In addition, this solid polyelectrolyte film is disposed between a fuel electrode and an air electrode to fabricate a fuel cell.

A covalent crosslinking of ion-conducting materials via sulfonic acid groups can be applied to various low cost electrolyte membrane base materials for improved fuel cell performance metrics relative to such base material. This proposed approach is due, in part, to the observation that many aromatic and aliphatic polymer materials have significant potential as proton exchange membranes if a modification can increase their physical and chemical stabilities without sacrificing electrochemical performance or significantly increasing the material and production costs.

The present invention relates to a solid polymer electrolyte membrane having both of a higher proton conductivity and a smaller methanol permeability, which can be produced by conducting a graft polymerization of a fluororesin thin membrane irradiated with a radiation with a monofunctional monomer and again irradiating the resulting film with a radiation, followed by conducting a graft polymerization thereof with a polyfunctional monomer; and a high-performance fuel cell comprising the solid polymer electrolyte membrane, a fuel electrode and an air electrode, said solid polymer electrolyte membrane being disposed between the fuel electrode and the air electrode.

An acid-base proton conducting polymer blend membrane is provided. The acid-base proton conducting polymer blend membrane comprises a first acidic polymer having acidic subunits, a second basic polymer having basic subunits, and a third polymer containing one or more functional units for improving membrane conductivity, flexibility, water remaining ability, dimension stability, and methanol crossover. In one embodiment, the acid-base polymer blend membrane of the present invention comprises a first acidic polymer having acidic subunits, a second basic polymer having basic subunits, wherein at least one of the first acidic and second basic polymer comprises one or more functional units to improve the properties of the membrane. The functional units include hydrophilic units, methanol blocking units, methanol blocking units, dimensional stabilizer units, and flexible units.

A curable resin composition for fuel cell electrolyte films characterized by comprising (1) 100 parts by mass of a monomer having at least one ethylenically unsaturated group per molecule and having, per molecule, either at least one, tonically conductive group or at least one precursor group capable of giving an tonically conductive group through a chemical reaction, (2) 10-400 parts by mass of an oligomer which has, per molecule, at least two reactive groups copolymerizable with the ethylenically unsaturated group of the ingredient (1) and has a number-average molecular weight of 400 or higher, (3) 10-400 parts by mass of a fluororesin, and (4) 0-2,000 parts by mass of a solvent.

The method includes steps: first, positive ionized Nano Pd granules is synthesized from Pd salt deoxidized in aqueous solution of cation polymer in ammonium class and reducing agent; then, fluorosulfuric acid type proton exchange membrane is dipped in water decentralization liquid of positive ionized Nano Pd granules; thus, Pd granules are static self-assembled to exit and entrance of sulfonic acid radical group in methanol infiltration channels formed on surface of proton exchange membrane so as to reduce penetrability of methanol to membrane. Advantages are: less loading noble metal Pd, and no inference on proton conducting power basically.

The invention belongs to the technical field of membranes and particularly relates to a PVDF (polyvinylidene fluoride) modified perfluorosulfonate proton exchange membrane and a preparation method thereof. PVDF is compounded with a perfluorosulfonate proton exchange membrane uniformly through the crosslinking of ammonia to prepare the PVDF modified perfluorosulfonate proton exchange membrane. The membrane permeability of the obtained PVDF modified perfluorosulfonate proton exchange membrane is reduced greatly compared with that of the perfluorosulfonate proton exchange membrane, and the membrane permeability of the PVDF modified perfluorosulfonate proton exchange membrane is reduced manyfold under the harsh conditions of high temperature and/or high concentration of methanol. In addition, the proton conductivity of the PVDF modified perfluorosulfonate proton exchange membrane is increased slightly under the same condition, and the mechanical stability and the dimensional stability of the compound proton exchange membrane are improved greatly. The preparation method disclosed by the invention has the advantages of simple operation process, mild preparation condition and extremely low production cost, is suitable for batch production and scale production and has good industrial production basis and broad application prospect.

The invention relates to a low-swelling sulfonated polyimide proton exchange membrane and the preparation method thereof. The preparation method of the low-swelling sulphonation polyimide proton exchange membrane adopts the steps that novel diamine monomer with terminal sulfonic acid alkyl branched chain is obtained through friedel-acrafts acylation reaction, polycondensing and ether becoming reaction and sulfurous acid displacing reaction, then the novel diamine monomer and aromatic dianhydride monomer generate reaction, polyimide copolymer with sulfonic acid alkyl branched chain is obtained and dissolved in N-methyl-2-ketoyrrolidine, finally the solution is poured on a glass flat plate and coated in a flow-casting way, the vacuum drying operation is performed, and the low-swelling sulfonated polyimide proton exchange membrane is obtained. The low-swelling sulfonated polyimide proton exchange membrane obtained by utilizing the preparation method has the advantages of high proton conductivity and low methanol penetrability; simultaneously, good low-swelling property is provided, therefore, the low-swelling sulfonated polyimide proton exchange membrane has extensive application prospect in the methanol fuel cell field.

The invention relates to a preparation method of a polymer matrix proton exchange membrane (PEM) with a cross-linked structure, belonging to the field of battery electrolyte materials. The PEM is prepared by carrying out mechanical blending dispersion on matrix polymer material, unsaturated metal organic sulfonate, peroxide and auxiliary crosslinking agent, carrying out reaction in situ at the temperature of 140-200 DEG C, treating the product of the reaction by deionized water and sulfuric acid solution, and drying; and the PEM comprises the components in parts by weight: (1) 100 parts of matrix polymer material, (2) 20-150 parts of unsaturated metal organic sulfonate, (3) 1-20 parts of peroxide and (4) 0-5 parts of auxiliary crosslinking agent. In the molding process, organic solvent is not needed; and the preparation method is simple, high in efficiency, environment-friendly and low in cost. The prepared PEM has the proton conductivity approximate to Nafion (reaching up to the order of magnitude of 10<-2>/ cm) and the methanol permeability coefficient far less than Nafion at the temperature of 20-80 DEG C, thus meeting the using requirement of a direct methanoi fuel cell.

Belonging to the field of high polymer materials, the invention relates to branched sulfonated polyaryletherketone containing a benzoxazole ring side group, a preparation method and application thereof. The method includes: firstly conducting a nucleophilic polycondensation reaction, taking trifunctional 1, 3, 5-trifluorobenzene carbonylbenzene as a branching unit to prepare allyl-containing branched sulfonated polyaryletherketone of different sulfonation degrees and different branching degrees, and then introducing a benzoxazole ring into the side group position of the polymer. The branched sulfonated polyaryletherketone polymer film containing the benzoxazole ring side group provided by the invention has good dimensional stability, low methanol permeability, high oxidation stability and good proton conductivity, thus being able to satisfy the requirements of a fuel cell proton exchange membrane.

The invention discloses a crosslinked proton exchange membrane with a specific oriented structure and a preparation method thereof, which belong to the field of fuel cell polymer electrolyte materials. The crosslinked proton exchange membrane consists of an ion exchange resin containing a sulfonic acid group, wherein the ion exchange resin containing the sulfonic acid group is a sulfonated non-fluorohydrocarbon polymer with a proton exchange function. The preparation method comprises the following steps of: dissolving the ion exchange resin containing the sulfonic acid group into a solvent to prepare a solution; performing curtain coating and membrane forming; stretching the prepared membrane under the condition that the solvent is not removed completely; after stretching is completed, maintaining external force to keep the membrane in a stretching state; drying the stretched membrane to remove residual solvent; performing heat cross-linking in a vacuum drying oven; cooling at the room temperature; and removing external force. The membrane material has high proton conductivity and low methanol permeability, and can be taken as a polymer electrolyte material for being directly applied to methanol fuel cells.

The invention relates to a free-standing composite proton conducting film and a preparation method thereof in the technical field of a fuel cell. The free-standing composite proton conducting film is formed by overlapping an organic proton conducting film layer and an inorganic proton conducting film layer, wherein, the inorganic proton conducting film layer is metallic oxide or phosphorus-containing metallic oxide with proton conducting capacity, and the organic proton conducting film layer is polymer with the proton conducting capacity. The free-standing composite proton conducting film is obtained by dissolving a sacrificial layer, the problems of no flexibility of the inorganic proton conducting film layer and high methanol permeability of the organic proton conducting film layer are overcome, and the free-standing composite proton conducting film with proton conducting capacity and very low methanol permeability is obtained, so as to solve the technical problems in the prior art.

The invention belongs to the field of membrane science, and particularly relates to a semi-ipn (interpenetrating polymer network) proton exchange membrane and a preparation method thereof. The preparation method comprises steps of dissolving sulfoacid polymer, 2-acrylamide-2-methyl propane sulfonic acid, ethylene glycol dimethacrylate and diphenyl ketone into polar solvent, heating the obtained solution at certain temperature so as to volatilize the solvent to obtain gel state membrane when a certain content of residual solvent is left, irradiating the obtained gel state membrane by an ultraviolet lamp for a certain time, soaking by dilute sulphuric acid and water so as to remove all left solvent, converting all sulfoacid group in the membrane into acid so as to obtain the semi-ipn proton exchange membrane. The proton exchange membrane material prepared by the method has high proton conductivity, low methanol permeability and reliable dimensional stability, and can be used in direct-methanol fuel cells.

The invention discloses a method for raising the anti-carbinol permeability of the proton exchange membrane containing fluorine sulfonic. The method is to put the proton exchange membrane containing fluorine sulfonic in the diffusion pool; use the mutual electrostatic action between the sulfonic group and conducting polymer monomers, which makes the conducting polymer monomers cross the proton exchange membrane containing fluorine sulfonic to the oxidizing agent side of the diffusion pool; and by a method of chemical polymerization diffusion in-situ, the conducting polymer monomers polymerized inside the proton exchange membrane containing fluorine sulfonic or on the facial sulfonic group cluster; under the conditions of few decreases in the electrical conductivity, the anti-carbinol permeability may be efficiently raised, and the carbinol transmission factor can be reduced by 1 to 2 magnitudes.