Abstract:
A proton-conducting polymer membrane comprising polyazoles containing phosphonic acid groups is obtainable by a process comprising: A) mixing one or more aromatic or heteroaromatic tetraamino compounds with one or more aromatic or heteroaromatic carboxylic acids or derivatives thereof which contain at least two acid groups per carboxylic acid monomer, with at least part of the tetraamino compounds or the carboxylic acids comprising at least one phosphonic acid group, or mixing of one or more aromatic or heteroaromatic diaminocarboxylic acids, of which at least part comprises phosphonic acid groups, in polyphosphoric acid to form a solution or dispersion; B) optionally heating the solution or dispersion obtained by step A) under inert gas to temperatures of up to 350° C. to form polyazole polymers; C) applying a layer using the mixture from step A) or B) to a support, thus forming a membrane, and D) partially hydrolyzing the polyphosphoric acid moieties of the membrane from step C) until it is self-supporting.
Abstract:
Liquid crystal polyester derived from phenylene-naphthalene monomers and one or more comonomers display an improved balance of properties, including low melt viscosity, fast cycle time in molding, very low mold shrinkage, high tensile and/or flexural strength, solvent resistance, excellent barrier properties, low water absorption, low thermal expansion coefficient, excellent thermostability, and/or low flammability. The phenylene-naphthalene monomers are The one or more comonomers include 4-hydroxybenzoic acid, 2-hydroxy-6-naphthoic acid, terephthalic acid, isophthalic acid, and derivatives and combinations thereof.
Abstract:
The invention under consideration concerns novel his-molecular-weight polyazoles, which are suitable for the production of fibers, films, membranes, and molded articles, on the basis of their high molecular weight, expressed as intrinsic viscosity, of at least 1.3 dl/g. Moreover, the invention under consideration describes a method for the production of high-molecular-weight polyazoles.
Abstract:
The present invention relates to novel polyazoles, a proton-conducting polymer membrane based on these polyazoles and its use as polymer electrolyte membrane (PEM) for producing membrane-electrode units for PEM-fuel cells, and also other shaped bodies comprising such polyazoles.
Abstract:
The present invention relates to proton-conducting polymer membranes which comprise polyazoles containing phosphonic acid groups and are obtainable by a process comprising the steps A) mixing of one or more aromatic and/or heteroaromatic tetraamino compounds with one or more aromatic and/or heteroaromatic carboxylic acids or derivatives thereof which contain at least two acid groups per carboxylic acid monomer, with at least part of the tetraamino compounds and/or the carboxylic acids comprising at least one phosphonic acid group, or mixing of one or more aromatic and/or heteroaromatic diaminocarboxylic acids, of which at least part comprises phosphonic acid groups, in polyphosphoric acid to form a solution and/or dispersion, B) heating of the solution and/or dispersion obtainable according to step A) under inert gas at temperatures of up to 350° C. to form polyazole polymers, C) application of a layer using the mixture from step A) and/or B) to a support, D) treatment of the membrane formed in step C) until it is self-supporting.
Abstract:
Methods for purifying a hydrogen gas stream are provided that can include: introducing the hydrogen gas stream into the hydrogen pumping cell, and collecting a purified hydrogen gas from the hydrogen pumping cell. The hydrogen gas stream can include hydrogen sulfide in an amount of about 10 ppm to about 1,000 ppm, and can have a relative humidity of about 0.1% or more at the operational temperature and pressure of the hydrogen pumping cell.
Abstract:
An intermediate compound for forming a RAFT agent is provided that can have the formula: where n is an integer from 1 to 20; m is an integer from 0 to 20; R1 is H, an alkyl group, or a cyano group; R2 is H, an alkyl group, or a cyano group; Y is OH, COOH, or NH2; and X is OH, COOH, NH2, a nitrobenzyl, benzyl, or para-methyl benzyl group. A RAFT agent is also provided that comprises a thiocarbonylthio-containing organic compound having a phosphonic end group. A method is also provided for forming a polymer chain on a surface of a nanoparticle utilizing the RAFT agent, along with nanoparticles and nanocomposites formed therefrom.
Abstract:
The present invention relates to novel polyazoles, a proton-conducting polymer membrane based on these polyazoles and its use as polymer electrolyte membrane (PEM) for producing membrane-electrode units for PEM-fuel cells, and also other shaped bodies comprising such polyazoles.
Abstract:
The present invention includes a method for preparing a nanoparticle filled nanocomposite material, the method including the steps of providing a plurality of nanoparticles. attaching a first layer of organic ligand to the nanoparticle via a phosphate or phosphonate linkage, covalently attaching a second layer of matrix compatible polymer to said first layer of organic ligand to produce modified nanoparticles, providing a polymer matrix and dispersing the modified nanoparticles in the polymer matrix, wherein the dispersement of the modified nanoparticles into the polymer matrix results in a nanocomposite material, and wherein the modified nanoparticles are modified such that the first layer is proximal to the nanoparticle and the second layer is distal to the nanoparticle. Also within the scope of the invention are modified nanoparticles, alternative nanocomposite materials and methods of making the same.
Abstract:
The present invention relates to a proton-conducting polymer membrane which comprises polyazoles and is coated with a catalyst layer and is obtainable by a process comprising the steps A) preparation of a mixture comprising polyphosphoric acid, at least one polyazole (polymer A) and/or one or more compounds which are suitable for forming polyazoles under the action of heat according to step B), B) heating of the mixture obtainable according to step A) under inert gas to temperatures of up to 400° C., C) application of a layer using the mixture obtained according to step A) and/or B) to a support, D) treatment of the membrane formed in step C) until it is self-supporting, E) application of at least one catalyst-containing coating to the membrane formed in step C) and/or in step D).