One method as described herein relates to making a membrane comprising an uncrosslinked high molecular weight polyimide polymer with a small amount of bulky diamine. Also as described herein is a hollow fiber polymer membrane comprising an uncrosslinked high molecular weight polyimide polymer with a small amount of bulky diamine. The polyimide polymers include monomers comprising dianhydride monomers, diamino monomers without carboxylic acid functional groups, and optionally diamino monomers with carboxylic acid functional groups, wherein 2 to 10 mole % of the diamino monomers are bulky diamino compounds and the ratio of diamino monomers with carboxylic acid functional groups to diamino monomers without carboxylic acid functional groups is 0 to 2:3. These uncrosslinked high molecular weight polyimide polymers with a small amount of bulky diamine are useful in forming polymer membranes with high permeance and good selectivity that are useful for the separation of fluid mixtures.

One method as described herein relates to making a membrane comprising an uncrosslinked high molecular weight, monoesterified polyimide polymer with a small amount of bulky diamine. These uncrosslinked high molecular weight, monoesterified polyimide polymers with a small amount of bulky diamine are useful in forming polymer membranes with high permeance and good selectivity that are useful for the separation of fluid mixtures. Also as described herein is a hollow fiber polymer membrane comprising an uncrosslinked high molecular weight, monoesterified polyimide polymer with a small amount of bulky diamine. The small amount of bulky diamine allows for formation of a membrane comprising the uncrosslinked polymer that exhibits high permeance and good selectivity.

An object of the present invention is to provide a separation membrane having high mechanical strength and being less likely to cause clogging and capable of continuously maintaining high water permeation performance. The present invention relates to a separation membrane characterized in that the average diameter D1 of a spherical structure in a region within 10 m from a first surface in a separation membrane having a spherical structure layer formed of a thermoplastic resin and the average diameter D2 of a spherical structure in a region of 10 m to 20 m from a second surface satisfy the relational expression of D1>D2 and the average diameter D1 and the average diameter D3 of a spherical structure in a third region satisfy the relational expression of 1.10<D1/D3<4.00.

The present invention relates to a method of making a monolith having a plurality of channels extending therethrough, the method comprising,

providing a suspension of polymer-coated particles in a first solvent;

extruding the suspension from a primary orifice, while passing one or more second solvents from a plurality of secondary orifices arranged within the first orifice, into a third solvent, whereby a monolith precursor is formed from the polymer and particles,

and sintering the monolith precursor to form a monolith.

The present invention relates to a hollow microfiber comprising (1) one or more cell-adhesive layers having a cell-adhesive hydrogel, (2) an outer shell layer having a high-strength hydrogel that covers the outer periphery of the cell-adhesive layer that is positioned farthest from the center axis among the one or more cell-adhesive layers, and (3) a cell layer that covers the inner periphery of the cell-adhesive layer that is positioned closest to the center axis among the one or more cell-adhesive layers. The present invention also relates to a method of manufacturing the hollow microfiber and a kit for carrying out the manufacturing method.

Various methods of making a reinforced membrane, devices for making the membranes, and the resulting membranes are described. The methods typically provide a reinforcing structure that includes filaments extending around the circumference of the membrane but without the filaments being part of a braided or woven structure. Some of the reinforcing structures also include longitudinal filaments. The methods and devices can be used to make a supporting structure in line with membrane formation steps, and also allow for a reinforced membrane to be produced that has a ratio of inside-to-outside diameters of 0.5 or more.

A porous membrane made from a poly(phenylene ether) copolymer has at least one of: a molecular weight cut off of less than 40 kilodaltons or a surface pore size of 0.001 to 0.1 micrometers. The porous membrane is made by dissolving the poly(phenylene ether) copolymer in a water-miscible polar aprotic solvent to form a porous membrane-forming composition; and phase-inverting the porous asymmetric membrane forming-composition in a first non-solvent composition to form the porous mem-brane. The porous membrane can be in the form of a sheet or a hollow fiber, and can be fabricated into separation modules.

A porous membrane made from a poly(phenylene ether) copolymer has at least one of: a molecular weight cut off of less than 40 kilodaltons or a surface pore size of 0.001 to 0.1 micrometers. The porous membrane is made by dissolving the poly(phenylene ether) copolymer in a water-miscible polar aprotic solvent to form a porous membrane-forming composition; and phase-inverting the porous asymmetric membrane forming-composition in a first non-solvent composition to form the porous membrane. The porous membrane can be in the form of a sheet or a hollow fiber, and can be fabricated into separation modules.

The invention, belonging to the field of membrane technology, presents a method for the high-throughput preparation of carbon nanotube hollow fiber membranes. This method contains three major steps. Firstly, the pristine carbon nanotubes (CNTs) are added into a mixture of concentrated nitric acid and sulfuric acid, which is then heated at 4080 C. for 0.56 hours. Secondly, the surface-functionalized CNTs and polyvinyl butyral (PVB) are dispersed and dissolved, respectively, in organic solvents at a mass ratio of 1:0.21:48 to form homogeneous spinning solution, which is squeezed into water as shell liquid with water as core liquid at a flow rate ratios of 0.55:1 through a spinneret to form CNT/PVB hollow fibers. Finally, the dry fibers are calcinated at 6001000 C. for 14 hours in absence of oxygen to produce free-standing CNT hollow fiber membranes. The method involved in this invention is simple and highly efficient without needing any templates, expensive apparatuses and chemicals. Additionally, the obtained electrically conductive CNT hollow fiber membranes feature a high porosity, high water flux and strong acid/alkali resistance.

The invention relates to the technical field of membrane separation, and discloses a hollow fiber membrane and preparation method and use thereof. The hollow fiber membrane includes a support, a selective layer, and a transition layer between the support and the selective layer, wherein at least a portion of the transition layer is embedded in the support. The hollow fiber membrane has a high selectivity and good mechanical properties.