The present disclosure relates to a composite membrane formed by lamination of two or more separate porous polymeric layers, as well as to a method and system for lamination. Advantageously, the resulting composite is a single layer, being difficult to separate into its component layers, yet effectively maintains the filtering capabilities of the component layers when not laminated.

A method of forming an unsintered biaxially expanded PTFE/thermoplastic polymer composite membrane is provided. The method includes blending fibrillatable polytetrafluoroethylene (PTFE) particles and thermoplastic polymer particles where the melting point of the thermoplastic polymer particles is less than the melting point of the fibrillatable PTFE particles. The method further includes forming the blend into a tape and expanding and heating the tape in a first direction at a first temperature. The expanded tape is then expanded, either concurrently or sequentially in a second direction to form an ePTFE composite membrane. The method does not include a sintering temperature. The ePTFE particles and thermoplastic polymer particles have an average particle size of less than 1 μm. In addition, the ePTFE composite membrane has a geometric mean matrix modulus to geometric mean matrix tensile strength ratio of at least about 6 and an absolute dimensional change percentage of less than about 1.5%.

The present disclosure provides the synthesis of an imidazolium-based functional ionic liquid copolymer (PMMA-b-PIL-R*) and a preparation method of an alloy ultra-filtration membrane. Firstly, PMMA-b-PIL-R* is prepared from methyl methacrylate (MMA) and polymerizable imidazolium-based functional ionic liquid (IL-R*) containing double bonding as the reactive monomers through sequential radical polymerization. With the use of a non-solvent induced phase separation method, PMMA-b-PIL-R* is introduced into the body of a polymeric membrane material, so as to prepare an alloy ultra-filtration membrane. A hydrogen-bond interaction is generated between the carbonyl in the molecular chain of PMMA-b-PIL-R* and the H . . . C—Cl structure in the molecular chain of the polymeric membrane material, which enhances the compatibility between the molecular chains of PMMA-b-PIL-R* and the polymeric membrane material, so that it can be stable in the ultra-filtration membrane; the imidazole groups and functional groups in the molecular chain of PMMA-b-PIL-R* can provide a good hydrophilicity.

An object of the present invention is to provide a separation membrane having high permeability and selective removability of divalent/monovalent ions. The separation membrane of the present invention includes a supporting membrane and a separation functional layer formed on the supporting membrane, in which the separation functional layer contains a polymerized product of a polyfunctional amine with a polyfunctional acid halide, the polyfunctional amine contains a polyfunctional aliphatic amine as a main component, the separation functional layer has a hollow protuberant structure, and the separation functional layer has a relative surface area of 1.1-10.0.

The present invention relates to a continuous process for preparing permselective hollow fiber membranes being suitable e.g. for hemodialysis, hemodiafiltration and hemofiltration of blood which comprises a two-stage drying and tempering treatment of the hollow fiber membranes. According to a further aspect, the invention relates to a continuous process for drying permselective hollow fiber membranes on-line. The invention also relates to devices for on-line drying of permselective hollow fiber membranes.

A hollow fiber membrane for separating blood plasma from blood, comprising a blood contact layer and a support layer each comprising a hydrophobic polymer, a hydrophilic polymer and vitamin E, and a method for producing said hollow fiber membrane to provide a hollow fiber membrane is described. The hollow fiber membrane is characterized by a reduced hemolysis activity so that the hollow fiber membrane can be advantageously used in plasmapheresis methods.

Disclosed are a CMS membrane, characterized in that it is obtainable by pyrolysis of a polyimide composed of the monomers 1-(4-aminophenyl)-1,3,3-trimethyl-2H-inden-5-amine and 5-(1,3-dioxo-2-benzofuran-5-carbonyl-2-benzofuran-1,3-dione of the following formulae: ##STR00001##
preferably by pyrolysis of the polyimide having the CAS number 62929-02-6, and a supported CMS membrane comprising a CMS membrane obtainable from a polyimide by pyrolysis and a porous support, characterized in that a mesoporous intermediate layer is provided between the CMS membrane and the porous support. Further disclosed are a process for preparing the supported membrane, the use of the membranes for separating gas mixtures or liquid mixtures, an apparatus for gas separation or for liquid separation, and the use of the polyimide for preparing a CMS membrane by pyrolysis.

A carbon molecular sieve (CMS) membrane having improved separation characteristics for separating olefins from their corresponding paraffins is comprised of carbon with at most trace amounts of sulfur and a group 13 metal. The CMS membrane may be made by pyrolyzing a precursor polymer devoid of sulfur in which the precursor polymer has had a group 13 metal incorporated into it, wherein the metal is in a reduced state. The pyrolyzing for the precursor having the group 13 metal incorporated into it is performed in a nonoxidizing atmosphere and at a heating rate and temperature such that the metal in a reduced state (e.g., covalently bonded to carbon or nitrogen or in the metal state).

The invention relates to membranes, monomers and polymers. The monomers can form polymers, which can be used for membranes. The membranes can be used in alkaline fuel cells, for water purification, for electrolysis, for flow batteries, and for anti-bacterial membranes and materials, as well as membrane electrode assemblies for fuel cells. In addition to the membranes, polymers and monomers and methods of using the membranes, the present invention also relates to methods of making the membranes, monomers and polymers.

The invention relates to a method for manufacturing a hollow fiber membrane bundle from a plurality of polysulfone and PVP-based hollow fiber membranes which encompasses the providing of a spinning solution comprising a polysulfone-based material, in particular polysulfone, a vinylpyrrolidone-based polymer, in particular polyvinylpyrrolidone, an aprotic solvent, in particular dimethylacetamide, providing a coagulant liquid comprising water and an aprotic solvent, in particular dimethylacetamide, co-extruding the spinning solution and the coagulant liquid through a concentric annular spinneret into a hollow strand, whereby the cavity of the strand is filled with coagulant liquid, conducting the strand through a precipitation gap, introducing the strand into a precipitating bath comprised substantially of water so as to obtain a hollow fiber membrane, conducting the hollow fiber membranes through at least one rinsing bath and drying the hollow fiber membrane obtained, arranging the resulting hollow fiber membranes into a hollow fiber membrane bundle, and treating the hollow fiber membrane bundle with water vapor.