An object of the present invention is to provide a multilayer separation membrane having excellent performance on both removal of suspended solids in water and adsorptive removal of metal ions in water. A multilayer separation membrane of the present invention includes: a porous adsorption layer including substantially a polymer having chelating functional groups; and a porous clarification layer, and the porous clarification layer is disposed neater to a raw water-side than the porous adsorption layer.

The present invention is an integral multilayered composite membrane having at least one ultrafiltration layer made by cocasting or sequentially casting a plurality of polymer solutions onto a support to form a multilayered liquid sheet and immersing the sheet into a liquid coagulation bath to effect phase separation and form a multilayered composite membrane having at least one ultrafiltration layer.

The invention relates to polymer powders, preferably fluoropolymer powders such as polyvinylidene fluoride (such as Kynar resins from Arkema Inc.), polyvinyl fluoride, and poly-ethylene-co-chlorotrifluoroethylene, useful for a high-solids liquid slurry. The PVDF has a narrow average particle size of from 20 to 100 microns, with less than 20 weight percent of particles outside this range. This powder can be used to form slurries having from 30 to 60 weight percent solids, the liquid slurries formed being free-flowing. The free-flowing slurries are useful in forming membranes in a thermally induced phase separation (TIPS) process.

An object of the present invention is to provide a porous hollow-fiber membrane having high strength while maintaining high pure-water permeation performance. A porous hollow-fiber membrane of the present invention is a porous hollow-fiber membrane including a fluororesin-based polymer, in which the porous hollow-fiber membrane has a columnar texture oriented in a longitudinal direction of the porous hollow-fiber membrane, and a molecular chain of the fluororesin-based polymer is oriented in the longitudinal direction of the porous hollow-fiber membrane.

The invention relates to a membrane having a pore-free separating layer including a polymer mixture for separating simple alcohols and water from their mixtures with other organic fluids by means of pervaporation or vapor permeation. In accordance with the invention, the polymer mixture is composed of at least two polymer components which are taken from the group of polymer components which includes of the following polymer components: Polyvinyl alcohol, other polymers such as poly NN-dimethylaminoethyl methacrylate (poly DMAEMA), a copolymer of DMAEMA and N-vinyl pyrrolidone (NVP) or of DMAEMA and N-vinyl caprolactam (NVCL), a terpolymer of DMAE, NVP and NVCL or of vinyl acetate ethylene vinyl chloride or from vinyl chloride ethylene acrylic ester or from vinyl acetate vinyl chloride acrylic ester. The invention further relates to the use and to a method for manufacturing a membrane in accordance with the invention.

The present invention is an integral multilayered composite membrane having at least one ultrafiltration layer made by cocasting or sequentially casting a plurality of polymer solutions onto a support to form a multilayered liquid sheet and immersing the sheet into a liquid coagulation bath to effect phase separation and form a multilayered composite membrane having at least one ultrafiltration layer.

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.

The present invention is an integral multilayered composite membrane having at least one ultrafiltration layer made by cocasting or sequentially casting a plurality of polymer solutions onto a support to form a multilayered liquid sheet and immersing the sheet into a liquid coagulation bath to effect phase separation and form a multilayered composite membrane having at least one ultrafiltration layer.

The present disclosure features a crosslinked arylimidazolium polymer membrane, the method of making, and uses thereof. The disclosed crosslinked arylimidazolium polymer membrane yields desirable mechanical properties, and can be incorporated into an electrochemical device such as a fuel cell, an electrolyzer, a redox flow battery, or another electrochemical device.

The present disclosure provides a porous hollow fiber membrane that exhibits blocking performance and water permeability performance suitable for filtration applications, as well as having excellent chemical resistance. In order to provide a solution to the above issue, the porous hollow fiber membrane of the present disclosure is made of a thermoplastic resin, wherein the crystallization onset temperature is 140 C. or lower, and the enthalpy of crystal fusion at and below the crystallization onset temperature is 10 J/g or less.