The present invention aims to provide a porous separation membrane that does not suffer a significant decrease in the protein permeability even after long term use. The porous separation membrane has an asymmetric structure with a dense layer forming one surface layer and with a coarse layer forming the other surface layer, supports a biocompatible polymer, and meet the requirements (1) and (2) given below in surface analysis of a cross section containing the dense layer and the coarse layer performed by TOF-SIMS: (1) the minimum value of normalized intensity of the ion signal attributed to the biocompatible polymer in the coarse layer is 0.15 times or more of the maximum value, and (2) the normalized average intensity of the ion signal attributed to the biocompatible polymer in the dense layer is 2.0 times or more of the normalized average intensity of the ion signal attributed to carboxylic acid in the coarse layer.

The present invention aims to provide a porous separation membrane that does not suffer a significant decrease in the protein permeability even after long term use. The porous separation membrane has an asymmetric structure with a dense layer forming one surface layer and with a coarse layer forming the other surface layer, supports a biocompatible polymer, and meet the requirements (1) and (2) given below in surface analysis of a cross section containing the dense layer and the coarse layer performed by TOF-SIMS: (1) the minimum value of normalized intensity of the ion signal attributed to the biocompatible polymer in the coarse layer is 0.15 times or more of the maximum value, and (2) the normalized average intensity of the ion signal attributed to the biocompatible polymer in the dense layer is 2.0 times or more of the normalized average intensity of the ion signal attributed to carboxylic acid in the coarse layer.

The present invention relates to new anion exchange polymers and (blend) membranes made from polymers containing highly fluorinated aromatic groups by means of nucleophilic substitution and processes for their production by means of nucleophilic aromatic substitution and their areas of application in membrane processes, in particular in electrochemical membrane processes such as fuel cells, electrolysis and redox flow batteries.

The present invention relates to new anion exchange polymers and (blend) membranes made from polymers containing highly fluorinated aromatic groups by means of nucleophilic substitution and processes for their production by means of nucleophilic aromatic substitution and their areas of application in membrane processes, in particular in electrochemical membrane processes such as fuel cells, electrolysis and redox flow batteries.

The present application relates to a multizone, unsupported, microporous, high throughput membrane. The membrane includes a first microporous zone, a second microporous zone, and a third microporous zone, where the third microporous zone is positioned between the first and second microporous zones, with the first, second, and third microporous zones being integral with one another. Further aspects of the present application include a process for making the membrane and a filtration cartridge with the membrane of the present application.

The present application relates to a multizone, unsupported, microporous, high throughput membrane. The membrane includes a first microporous zone, a second microporous zone, and a third microporous zone, where the third microporous zone is positioned between the first and second microporous zones, with the first, second, and third microporous zones being integral with one another. Further aspects of the present application include a process for making the membrane and a filtration cartridge with the membrane of the present application.

A crosslinked microporous membrane (crosslinked polymer) composition useful in gas separation, the membrane comprising: (i) an aromatic polymer containing a multiplicity of benzene rings; and (ii) a multiplicity of fluorinated aromatic moieties, each fluorinated aromatic moiety containing at least two separate methylene (—CH.sub.2—) linkages connected to benzene rings on the aromatic polymer; wherein the cross-linked microporous membrane possesses micropores having a pore size of up to 2 nm. Also described are methods for producing the crosslinked polymer and a microporous carbon material produced by pyrolysis of the crosslinked polymer membrane. Also described are methods for using the crosslinked polymer and microporous carbon material for gas or liquid separation, filtration, or purification.

A crosslinked microporous membrane (crosslinked polymer) composition useful in gas separation, the membrane comprising: (i) an aromatic polymer containing a multiplicity of benzene rings; and (ii) a multiplicity of fluorinated aromatic moieties, each fluorinated aromatic moiety containing at least two separate methylene (—CH.sub.2—) linkages connected to benzene rings on the aromatic polymer; wherein the cross-linked microporous membrane possesses micropores having a pore size of up to 2 nm. Also described are methods for producing the crosslinked polymer and a microporous carbon material produced by pyrolysis of the crosslinked polymer membrane. Also described are methods for using the crosslinked polymer and microporous carbon material for gas or liquid separation, filtration, or purification.

A polymer electrolyte membrane according to the present invention has a cluster diameter of 2.96 to 4.00 nm and a converted puncture strength of 300 gf/50 μm or more. The polymer electrolyte membrane according to the present invention has a low electric resistance and an excellent mechanical strength.

Described herein are water desalination membranes and methods of desalinating water. Sulfonated poly(arylene ether) polymers are also disclosed, including those comprising one or more sulfonate groups at various points along the polymer chain. The polymers may be used as at least a portion of a water desalination membrane. The polymers described herein are useful for preventing transport of aqueous ionic species (e.g., Na.sup.+ and Cl.sup.−) across a membrane made from the polymers while allowing water to pass. Chlorine-stable polymers are described, as well as polymers exhibiting good performance for rejecting monovalent cations in the presence of polyvalent cations.