A hollow fiber membrane that is a hollow fiber type semipermeable membrane, wherein a Raman value is 70% or more, and the Raman value is a ratio of a minimum value to a maximum value of peak intensities, which are intensities of maximum peaks in each of multiple Raman spectra obtained by Raman spectroscopy at multiple points in a membrane thickness direction of a transverse cross-section of the hollow fiber membrane in a state of being swollen with water.

A hollow fiber membrane and methods of making the hollow fiber membrane are described. The membrane includes a hydrophobic polymer such as polysulfone, a hydrophilic polymer such as polyvinylpyrrolidone (PVP), and a fluropolymer additive, and optionally a stabilizer, for instance, to stabilize the fluoropolymer additive in the membrane, particularly during conditioning or E-beam sterilization or both. Further conditioning improvements to membrane manufacturing are disclosed. The membrane may be incorporated into a dialysis filter for use in hemodialysis and related applications. The membrane has improved hemocompatibility, charge stability, or middle molecule clearance compared to conventional membranes. Also disclosed is a method of evaluating membrane charge stability.

The present invention relates to a process for the production of asymmetric cellulose hollow fibres and the use of such fibres in the production of asymmetric carbon hollow fibre membranes (CHFMs). In particular, the present invention provides a facile and scalable process for the preparation of asymmetric CHFMs by direct pyrolysis of polymeric precursors without the need for complex pre-pyrolysis treatment steps to prevent pore collapse. The present invention also relates to the use of asymmetric CHFMs prepared according to said process in the separation of hydrogen gas from a mixed gas source, especially in the separation of hydrogen from CO.sub.2 in the steam-methane reforming reaction.

A hollow fiber that generally extends in a longitudinal direction is provided. The hollow fiber comprises a hollow cavity that extends along at least a portion of the fiber in the longitudinal direction. The cavity is defined by an interior wall that is formed front a thermoplastic composition containing a continuous phase that includes a polyolefin matrix polymer and a nanoinclusion additive dispersed within the continuous phase in the form of discrete domains. A porous network is defined in the composition that includes a plurality of nanopores.

The invention relates to extracorporeal blood circuits, and components thereof (e.g., hollow fiber membranes, potted bundles, and blood tubing), including 0.005% to 10% (w/w) surface modifying macromolecule. The extracorporeal blood circuits have an antithrombogenic surface and can be used in hemofiltration, hemodialysis, hemodiafiltration, hemoconcentration, blood oxygenation, and related uses.

The disclosure provides a method for preparing a hollow fiber membrane by melt spinning-stretching and selective swelling, including: preparing a nascent hollow fiber by melt spinning in an inert gas protective atmosphere by using an amphiphilic block copolymer as a film forming material, and stretching the nascent hollow fiber in the cooling process, a stretch rate being controlled at 200-540 mm/min, and a stretch ratio being controlled at 150-600%; immersing the obtained hollow fiber in a swelling solvent, and treating the hollow fiber in a water bath at 65° C. for 1 h; and then transferring the hollow fiber into a long-chain alkane solvent, treating the hollow fiber at the same temperature for 1-12 h, and after the completion of the treatment, immediately taking out the hollow fiber and drying the hollow fiber to obtain the hollow fiber membrane with a bicontinuous porous structure. By combining the melt spinning-stretching and the selective swelling, the method of the disclosure can synchronously and continuously improve the permeability and selectivity of the hollow fiber membrane. The treatment in the long-chain alkane solvent can make the polar chain excessively enriched on the surface of the membrane migrate inward, thereby improving the performance of the hollow fiber membrane.

A hollow fiber that generally extends in a longitudinal direction is provided. The hollow fiber comprises a hollow cavity that extends along at least a portion of the fiber in the longitudinal direction. The cavity is defined by an interior wall that is formed from a thermoplastic composition containing a continuous phase that includes a polyolefin matrix polymer and a nanoinclusion additive dispersed within the continuous phase in the form of discrete domains. A porous network is defined in the composition that includes a plurality of nanopores.

System, devices, and method for the production of thin film composite hollow fiber membranes on a hollow fiber support structure. The system includes a comb and roller device, or comb and dual roller device, which can be used to define a submerged travel path in a first solution bath for a hollow fiber. The combs and rollers control the amount of time the hollow fiber spends in the first solution. The first solution contains a first monomer, and the hollow fiber is impregnated with the first monomer. The amount of impregnation depends on the time spent in the first solution. Subsequent immersion in a second solution containing a second monomer results in the formation of a thin film composite hollow fiber membrane.

A hollow fiber porous membrane includes polyethersulfone or polysulfone. The hollow fiber porous membrane has an inner diameter from 300 to 600 μm, a thickness from 70 to 200 μm, a molecular weight cut-off of 10000 or lower, and a plurality of pores having a pore diameter from 0.1 to 0.5 μm throughout an outer surface; and a swelling rate of less than 5% as defined below: Swelling Rate (%): for 20 or more of the hollow fiber porous membranes, after a membrane thickness in a cross section of each one of the hollow fiber porous membranes in the width direction is measured at randomly selected 10 or more locations, an average membrane thickness is calculated based on 200 or more locations in total, and the swelling rate is calculated by a formula below: Swelling Rate (%)=(location numbers where the membrane thickness as measured exceeded 1.3 times the average membrane thickness)/(membrane thickness measurement numbers)×100.

A hollow fiber that generally extends in a longitudinal direction is provided. The hollow fiber comprises a hollow cavity that extends along at least a portion of the fiber in the longitudinal direction. The cavity is defined by an interior wall that is formed front a thermoplastic composition containing a continuous phase that includes a polyolefin matrix polymer and a nanoinclusion additive dispersed within the continuous phase in the form of discrete domains. A porous network is defined in the composition that includes a plurality of nanopores.