The present invention relates to a composite porous hollow-fiber membrane including a first layer and a second layer which each include a fluororesin-based polymer, in which the first layer has a columnar texture oriented in a longitudinal direction of the composite porous hollow-fiber membrane, the columnar texture has an average value v of a Raman orientation parameter calculated with the specific formula, and the second layer has a three-dimensional network texture and has an average surface-pore diameter of 5.0 nm to 5.0 m.

An environmentally friendly closed loop manufacturing process (10.sub.1, 10.sub.2) produces microporous membranes (32) by cast or extrusion of polymer-plasticizer mixtures followed by non-porous film formation (20), extraction (22) of the plasticizer using an azeotrope solvent and thereby forming a solvent-laden sheet and a mixture of plasticizer and azeotrope solvent, distillation (28) of the mixture to separate the plasticizer and azeotrope solvent for reuse, evaporation (30) of the azeotrope solvent from the solvent-laden sheet to form the micropores, and capture of the resultant solvent vapor for subsequent adsorption-desorption of the azeotrope solvent from activated carbon (34) or by vapor condensation (36) for reuse in the manufacturing process. The azeotrope solvent is at least a two-component mixture of solvents, one of which is designed for efficient removal of the plasticizer, while the other component(s) render(s) the azeotrope solvent non-flammable.

The present invention relates to a hollow fiber membrane in which the thickness L of a spherical structure layer is 60-500 ?m (inclusive), the spherical structure layer has a first surface and a second surface, the average diameter Da.sub.1 of the spherical structure in a region Sa.sub.1 10 ?m or less from the first surface and the average diameter db.sub.2 of the spherical structure in a region Sb.sub.2 10-20 ?m from the second surface satisfy the relational expression Da.sub.1>db.sub.2, and the spherical structure satisfies certain parameters.

A process for preparing a composite membrane comprising the steps: a) applying a radiation-curable composition to a porous support; b) irradiating the composition present on the support, thereby forming a gutter layer of cured polymer; c) forming a discriminating layer on the gutter layer; and d) applying a radiation-curable composition to the discriminating layer and irradiating that composition, thereby forming a protective layer on the discriminating layer; wherein one or both of the radiation-curable compositions applied in steps a) and d) comprise a photo acid generator having an absorbency coefficient ? at 313 nm of more than 1?10.sup.4 mol.sup.?1*cm.sup.?1. Also claimed are composite membranes and gas separation cartridges comprising the membranes.

A system for degassing a hydrocarbon fluid from a hydrocarbon liquid has a plurality of hollow tube membranes. The hollow tube membranes are formed of a plastic providing an inner support body and an outer selective layer which is denser than the inner support body. The inner support body is formed of spherulitic structures. A fuel supply system and a method ae also disclosed.

A porous hollow fiber membrane includes at least a first solvent and a second solvent. The first solvent is at least one selected from sebacic acid esters, citric acid esters, acetyl citric acid esters, adipic acid esters, trimellitic acid esters, oleic acid esters, palmitic acid esters, stearic acid esters, phosphoric acid esters, C6-C30 fatty acids, and epoxidized vegetable oils. The second solvent is different from the first solvent, and is at least one selected from sebacic acid esters, citric acid esters, acetyl citric acid esters, adipic acid esters, trimellitic acid esters, oleic acid esters, palmitic acid esters, stearic acid esters, phosphoric acid esters, C6-C30 fatty acids, and epoxidized vegetable oils. The porous hollow fiber membrane has a three-dimensional network structure.

The present invention provides a porous hollow fiber membrane that has both high strength and high pure water permeability, and that exhibits excellent thermal deformation resistance. The present invention is related to a porous hollow fiber membrane containing a fluororesin-based polymer, and a manufacturing method of the membrane comprises a drawing step and a relaxing step. The porous hollow fiber membrane is characterized in that: the molecular chain of the polymer is oriented in the longitudinal direction of the hollow fiber membrane; and at the same time internal distortion of oriented non-crystalline chains, which is disadvantageous in terms of entropy, is alleviated.

A microporous membrane of a polyethylene-based composite material, including high density and high crystallinity of polyethylene as a base material. The polyethylene is modified by a modifying agent accounting for 10-25 wt. % of the membrane and including a moderate molecular weight of rubber selected from polyisobutylene (PIB), ethylene-propylene methylene copolymer (EPM), or a mixture thereof, the rubber having a dynamic viscosity of between 50 and 2000 Pa.Math.S at 100? C. and a weight average molecular weight of between 90,000 and 250,000. The modified polyethylene is dissolved in a solvent and a pore-forming agent for pore formation.

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.

A poly(methyl methacrylate) (PMMA) membrane having a highly porous, reticulated, 3-D structure suitable for lateral flow diagnostic applications is described. Also described is a method for producing a poly(methyl methacrylate) (PMMA) membrane that comprises the steps of mixing a suitable amount of PMMA, a solvent and a optionally one of either a co-solvent or a non-solvent to produce a solution, casting a thin film of the solution onto a support, and removal of the solvent from the solution to produce the PMMA membrane. A lateral flow diagnostic device comprising a highly porous PMMA membrane as a reaction membrane is also described.