A filter includes a fibrous substrate having a plurality of coextruded first polymer material fibers and second polymer material fibers. Each of the first and second fibers are separated from each other and have a rectangular cross-section defined in part by an additional encapsulating polymer material that is separated from the first polymer material fibers and second polymer material fibers. The fibrous substrate has a pore size range of between about 0.1 m to about 0.4 m.

Disclosed herein are asymmetric multilayer carbon molecular sieve (CMS) hollow fiber membranes and processes for preparing the membranes. The processes include simultaneously extruding a core dope containing a polymer and suitable nanoparticles, a sheath dope, and a bore fluid, followed by pyrolysis of the extruded fiber.

A polyolefin microporous membrane is disclosed. The membrane has a width of not less than 100 mm, and a variation range of an F25 value in a width direction is not greater than 1 MPa. The F25 value is a value obtained by dividing a load at 25% elongation of a sample of the laminated polyolefin microporous membrane as measured with a tensile testing machine by a cross-sectional area of the sample.

The invention relates to the use of special polymer layers as barriers, in particular as barrier layers in composite materials. Suitable polymers for the polymer layer are copolymers consisting of ethylene and vinyl alcohol or consisting of ethylene and carbon monoxide or consisting of ethylene and carbon monoxide and propylene. These barrier layers exhibit a selective barrier effect with respect to different gases, the barrier effect being especially effective with respect to HFOs. On account of these properties, such barrier layers can positively affect insulating properties, for example in thermally insulated pipes.

Provided is a microporous polyolefin membrane which has excellent oxidation resistance and electrolyte injection performance and further has excellent permeability and strength balance. The multilayer, microporous polyolefin membrane has a first microporous layer containing polypropylene. The electrolyte injection performance is 20 seconds or less, at least one surface layer is the first microporous layer, and the PP distribution in the first microporous layer is uniform in the in-plane direction.

A filter medium includes first and second porous films mainly containing fluororesin, and a pre-collection member upstream of the first film. The pre-collection member has a pressure drop when air is passed through at a flow rate of 5.3 cm/s of between 15 Pa and 55 Pa, a collection efficiency of NaCl particles having a particle diameter of 0.3 m when air containing the particles is passed through at a flow rate of 5.3 cm/s of between 25% and 80%, a thickness of 0.4 mm or less, and a PF value between 7 and 15. A ratio of the PF value of the pre-collection member to the PF value when the first and second films are overlapped, is between 0.20 and 0.45. The filter medium can be in a filter pack or filter unit, and produced by integrating the films and the pre-collection member using heat lamination.

A porous filter includes a porous laminate in which a plurality of biaxially stretched porous sheets made of PTFE are stacked. The Gurley number G and the bubble point B (kPa) of the porous laminate satisfy the following expressions (1) and (2):
log G>3.710.sup.3B0.8(1)
log G<4.910.sup.3B+0.45(2).

A method of manufacturing a separation membrane structure comprising a step of forming a first to n.sup.th zeolite membranes on a surface of a porous substrate by n repetitions (wherein n is an integer greater than or equal to 2) of formation of a zeolite membrane by a method of hydrothermal synthesis. The following formula (1) is established in relation to the step of forming the first to the n.sup.th zeolite membranes. (Formula 1) N.sub.1/N.sub.0+0.1T.sub.2n/T.sub.12N.sub.1/N.sub.0+2 (Wherein, N.sub.1 denotes a permeation rate of a predetermined gas in the substrate after formation of the first zeolite membrane, N.sub.0 denotes a permeation rate of a predetermined gas in the substrate before formation of the first zeolite membrane, T.sub.1 is a time required for formation of the first zeolite membrane, and T.sub.2n is a total time required for formation of the second to the n.sup.th zeolite membranes.)

Provided is a novel continuous single-step method of manufacturing a multilayer sorbent polymeric membrane having superior productivity, properties and performance. At least one layer of the polymeric membrane comprises sorbent materials and a plurality of interconnecting pores. The method includes: (a) coextruding layer-forming compositions to form a multilayer coextrudate; (b) casting the coextrudate into a film; (c) extracting the film with an extractant; and (d) removing the extractant from the extracted film to form the multilayer sorbent polymeric membrane. The sorbent membrane of this disclosure can find a wide range of applications for use in filtration, separation and purification of gases and fluids, CO.sub.2 and volatile capture, structural support, vehicle emission control, energy harvesting and storage, electrolyte batteries, device, protection, permeation, packaging, printing, and etc.

[Problem to be solved] To provide an ion exchange membrane, a method for producing an ion exchange membrane, and an electrolyzer that enable a reduction in electrolytic voltage when subjected to electrolysis.

[Solution] An ion exchange membrane including:

a membrane main body including a fluorine-containing polymer having an ion exchange group; and

a coating layer arranged on at least one face of the membrane main body;

wherein the coating layer includes inorganic particles and a binder,

a mass ratio of the binder to the total mass of the inorganic particles and the binder in the coating layer is more than 0.3 and 0.9 or less, and

a surface roughness of the coating layer is 1.20 m or more.