There is provided a multi-layered membrane for separating components in an aqueous sample. There is also provided a method of preparing said multi-layered membrane, a method of separating blood plasma from a whole blood sample and a diagnostic device for separation of blood plasma from a whole blood sample.

Polymer blends comprising an ortho-functionalized polyimide homo or copolymer and a polybenzimidazole homo or copolymer, wherein the ortho-functionalized polyimide thermally rearranges to a polymer comprising a phenylene heterocyclic group, such as, polybenzoxazole, polybenzothiazole, polybenzimidazole and/or other heterocyclic structure upon heating. Also disclosed are method of forming a polymer blend comprising dissolving an ortho-functionalized polyimide homo or copolymer and a polybenzimidazole homo or copolymer in a solvent, and optional compatibilizer, to form a polymer solution; contacting a support with the polymer solution; and evaporating the solvent to provide a thin layer comprising the polymer blend on the support. Further, methods of heat treating these polymer blends to thermally rearrange the disclosed polyimides are disclosed, as are the polymer blends prepared thereby. Methods of using these polymer blends to separate gases are also disclosed.

A hollow fibre membrane having a coiled, a hemihelix, a helical or an undulated native form, in which the membrane can be stretched by up to 4-times its original length with no plastic deformation, and wherein the native form of the membrane is produced by the asymmetric flow of liquid polymer through an opening of a die or nozzle.

Provided are porous polymeric filter membranes comprising a polymer having admixed therein at least one carbonaceous material. The membranes are capable of removing trace amounts of various impurities from a liquid composition, including metal ions, acids, bases, and organic contaminants.

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.

Hydrophobic flat membrane made from a vinylidene fluoride polymer with a wall, a first surface, and a second surface. The membrane has on its first surface a network structure with open pores and on its second surface a continuous skin in which pores are formed, and adjacent to the skin of the second surface a supporting layer with an isotropic pore structure across the wall thickness, wherein the supporting layer extends over at least 80% of the wall thickness and wherein the pores of the supporting layer have an average diameter of less than 1 μm. The weight average of the molecular weight M.sub.W of the vinylidene fluoride polymer lies in the range from 300 000 to 500 000 daltons, and the polydispersivity M.sub.W/M.sub.N is greater than 5.5.

The pores in the skin of the second surface have a closed perimeter in the plane of the skin and an average ratio of the extension in the direction of the longest axis thereof to the extension in the direction of the shortest axis thereof of at most 5. The pores in the first surface and second surface have an essentially isotropic distribution of their orientation. The porosity of the membrane lies in the range from 50 to 90 vol. % and the wall thickness in the range from 50 to 300 μm. The membrane has a maximum separating pore diameter d.sub.max in the range from 0.05 to 1.5 μm.

A hydrophobic biofilm membrane modified with a spiropolyurethane may be used for desalination of salt water to fresh water. The spiropolyurethane component of the membrane can produce a hydrophobic spin membrane boundary which attracts saline water, and where the hydrophobic spin membrane boundary can comprise a hinge-like motion for capture of salt molecules via a loose pore-gate spongy membrane surface texture while allowing desalinated water to flow through the porous membrane. The membrane is useful in both reverse osmosis (RO) and membrane distillation (MD) separations, including the desalination.

The invention relates to an apparatus and a method for the manufacture of at least one hollow fiber membrane, wherein a spinning mass is extruded via a spinning unit to form a spinning thread and precipitated in a precipitation bath to form a hollow fiber membrane and the hollow fiber membrane is optionally rinsed in a rinsing bath, wherein furthermore the hollow fiber membrane is passed through at least one drying unit, wherein the drying unit comprises a pressure section which is constructed in such a way that a positive pressure compared with atmospheric pressure can be set in the pressure section, and at least part of the precipitating agent or rinsing agent contained in the at least one hollow fiber membrane (104) is separated from the at least one hollow fiber membrane.

One aspect of the present disclosure provides a production method for a porous membrane including pores, and concave portions having an average opening diameter greater than an average pore diameter of the pores on at least one of a pair of main surfaces, the method including a step of forming the concave portion on a surface to be the main surface.

The invention relates to an apparatus and a method for the manufacture of at least one hollow fiber membrane, wherein a spinning mass is extruded via a spinning unit to form a spinning thread and precipitated in a precipitation bath to form a hollow fiber membrane and the hollow fiber membrane is optionally rinsed in a rinsing bath, wherein furthermore the hollow fiber membrane is passed through at least one drying unit, wherein the drying unit comprises a pressure section which is constructed in such a way that a positive pressure compared with atmospheric pressure can be set in the pressure section, and at least part of the precipitating agent or rinsing agent contained in the at least one hollow fiber membrane (104) is separated from the at least one hollow fiber membrane.