Disclosed are polymers suitable for hydrophilically modifying the surface of porous fluoropolymer supports, for example, a copolymer of the formula: ##STR00001## Also disclosed are a method of preparing the polymers, a method of hydrophilically modifying porous fluoropolymer supports, hydrophilic fluoropolymer porous membranes prepared from the polymers, and a method of filtering fluids through the porous membranes.

Disclosed are polymers suitable for hydrophilically modifying the surface of porous fluoropolymer supports, for example, a copolymer of the formula: ##STR00001## Also disclosed are a method of preparing the polymers, a method of hydrophilically modifying porous fluoropolymer supports, hydrophilic fluoropolymer porous membranes prepared from the polymers, and a method of filtering fluids through the porous membranes.

Disclosed are copolymers suitable for hydrophilically modifying the surface of fluoropolymer porous membranes, for example, a copolymer of the formula: ##STR00001##
wherein R, n, m, and x are as defined herein. Also disclosed are a method of preparing the copolymers, a method of hydrophilically modifying porous fluoropolymer supports, and composite hydrophilic fluoropolymer porous membranes prepared from the copolymers.

Disclosed are copolymers suitable for hydrophilically modifying the surface of fluoropolymer porous membranes, for example, a copolymer of the formula: ##STR00001##
wherein R, n, m, and x are as defined herein. Also disclosed are a method of preparing the copolymers, a method of hydrophilically modifying porous fluoropolymer supports, and composite hydrophilic fluoropolymer porous membranes prepared from the copolymers.

A membrane suitable for separating a gas from a gas mixture comprising a non cross-linked PVAm having a molecular weight of at least Mw 100,000 carried on a support wherein after casting onto the support, said PVAm has been heated to a temperature in the range 50 to 150 C., e.g. 80 to 120 C.

The present invention relates to the use of additives in processes to form polymeric fibers. These fibers can be formed into membranes with improved middle and/or higher molecular weight solute removal.

To provide a fluorinated copolymer which is capable of providing an ion exchange membrane having little adverse effect due to impurities in an alkali chloride aqueous solution on electrolysis of the alkali chloride aqueous solution. To use a fluorinated copolymer of a fluorinated monomer having a carboxylic acid type functional group with a fluorinated olefin, wherein the proportion of components having a common logarithm (log M) of a molecular weight M being from 2.0 to 3.5 is at most 10 mass % per 100 mass % of components having a common logarithm (log M) of a molecular weight M being at least 2.0, contained in a CClF.sub.2CF.sub.2CClFH soluble content.

To provide a fluorinated copolymer which is capable of providing an ion exchange membrane having little adverse effect due to impurities in an alkali chloride aqueous solution on electrolysis of the alkali chloride aqueous solution. To use a fluorinated copolymer of a fluorinated monomer having a carboxylic acid type functional group with a fluorinated olefin, wherein the proportion of components having a common logarithm (log M) of a molecular weight M being from 2.0 to 3.5 is at most 10 mass % per 100 mass % of components having a common logarithm (log M) of a molecular weight M being at least 2.0, contained in a CClF.sub.2CF.sub.2CClFH soluble content.

Disclosed are membranes formed from self-assembling block copolymers, for example, a diblock copolymer of the formula (I): ##STR00001##
wherein R.sup.1R.sup.4, n, and m are as described herein, which find use in preparing nanoporous membranes. Embodiments of the membranes contain the block copolymer that self-assembles into a cylindrical morphology. Also disclosed is a method of preparing such membrane which involves spray coating a polymer solution containing the diblock copolymer to obtain a thin film, followed by annealing the thin film in a solvent vapor and/or soaking in a solvent or mixture of solvents to form a nanoporous membrane.

Disclosed are self-assembled structures formed from self-assembling block copolymers, for example, a diblock copolymer of the formula (I): ##STR00001##
wherein R.sup.1-R.sup.4, n, and m are as described herein, which find use in preparing nanoporous membranes. In an embodiment, the block copolymer self-assembles into a cylindrical morphology. Also disclosed is a method of preparing such membrane which involves spin coating a polymer solution containing the block copolymer to obtain a thin film, followed by solvent annealing of the film. Further disclosed is a method of preparing porous membranes from the self-assembled structures.