The present invention pertains to a porous polyimide film production method and a porous polyimide film produced using said method, said method including: a step (1) in which a poly(amic acid) solution comprising 40%-97% by mass organic polar solvent and 3%-60% by mass poly(amic acid) having an intrinsic viscosity, comprising tetracarboxylic acid units and diamine units, of 1.0-3.0 is cast in film form and immersed in or caused to come in contact with a coagulating solvent having water as an essential component thereof, and a porous film of poly(amic acid) is produced; and a step (2) in which the porous film of poly(amic acid) obtained in said step is heat treated and imidized. Shrinkage in the film longitudinal direction and transverse direction after heat treatment is suppressed to no more than 8% for each direction and the speed of temperature increase in a temperature range of at least 200? C. during the heat treatment is at least 25? C./min.

A porous membrane is made from a poly(phenylene ether) copolymer containing 10 to 40 mole percent repeat units derived from 2-methyl-6-phenylphenol and 60 to 90 mole percent repeat units derived from 2,6-dimethylphenol; and a block copolymer containing backbone or pendant blocks of poly(C.sub.2-4 alkylene oxide). The porous membrane is made by dissolving the poly(phenylene ether) copolymer in a water-miscible polar aprotic solvent to form a membrane-forming composition; and phase-inverting the membrane forming-composition in a first non-solvent composition to form the porous membrane. A method of making a hollow fiber by coextrusion through a spinneret having an annulus and a bore, includes coextruding the membrane-forming composition through the annulus, and a first non-solvent composition through the bore, into a second non-solvent composition to form the hollow fiber.

A method for producing a porous resin particle including a mesoporous structure portion and an outer shell portion integrally formed on a surface of the mesoporous structure portion includes, in a state that an oil-phase liquid, in which a polymerizable monomer and an oil-soluble polymerization initiator having a polymerization initiating ability to the polymerizable monomer are dissolved or dispersed in a hydrophobic solvent, is dispersed as oil droplets in an aqueous medium containing a water-soluble polymerization initiator having a polymerization initiating ability to the polymerizable monomer, generating a plurality of mesopores inside the porous resin particle by forming a solid medium, by polymerizing the polymerizable monomer by acting the oil-soluble polymerization initiator and the water-soluble polymerization initiator at the same time on the polymerizable monomer.

The present invention relates to a porous membrane suitable for use in high pressure filtration method.

The present invention relates to a porous membrane including a polymer including a polyvinylidene fluoride-based resin as a main component, and a branched polyvinylidene fluoride-based resin as the polyvinylidene fluoride-based resin, in which the polymer has a value of a of 0.32 to 0.41 and a value of b of 0.18 to 0.42, each of which is determined by approximation according to the formula 1 below from a radius of gyration <S.sup.2>.sup.1/2 and an absolute molecular weight M.sub.w of the polymer which are measured by GPC-MALS (gel permeation chromatograph equipped with a multi-angle light scattering detector). <S.sup.2>.sup.1/2=bM.sub.w.sup.a (Formula 1).

A synthesis method for making an isocyanate based organic xerogel having a low density (i.e. <400 kg/m.sup.3) and a small pore size (<150 nm) in combination with a specific surface area >100 m.sup.2/g is disclosed.

The synthesis method avoiding or reducing gel shrinkage during the solvent removal step is characterized by the step wherein the organic solvent used to synthesize the isocyanate based organic xerogel is replaced by water such that during the solvent removal step only water needs to be removed to dry the porous network and to obtain the isocyanate based organic xerogel.

A polyvinylidene difluoride membrane is provided. The polyvinylidene difluoride membrane including polyvinylidene difluoride having a melt viscosity of 35 to 60 (k poise), and the surface of the polyvinylidene difluoride membrane has a pore size of 0.1 ?m to 5 ?m. A method of manufacturing a porous polyvinylidene difluoride membrane and a method of purifying brine are also provided. The method of purifying brine includes the above-mentioned polyvinylidene difluoride membrane.

A polypeptide porous body of the present invention is a porous body of a polypeptide derived from spider silk proteins. The polypeptide includes a water-insoluble polypeptide. The polypeptide porous body has an apparent density of 0.1 g/cm.sup.3 or less. A method for producing the polypeptide porous body includes: a solution production step in which the polypeptide is dissolved in at least one solvent selected from DMSO, DMF, and these with an inorganic salt, so as to obtain a solution of the polypeptide; a step in which the solution produced in the solution production step is substituted with a water-soluble solvent so as to obtain a polypeptide gel; and a step in which the polypeptide gel is dried. Thereby, the present invention provides a polypeptide porous body having excellent water absorbability and a polypeptide porous body suitable for application to a living body, and a method for producing the same.

A method of manufacturing a porous fluorine-containing polymer membrane is provided, which includes mixing a fluorine-containing polymer, a pore creating agent, and a solvent to form a mixture; forming a membrane of the mixture, and removing the pore creating agent and the solvent in the membrane to form the porous fluorine-containing polymer film. The pore creating agent has a chemical formula of ##STR00001##
wherein R.sup.1 is a C.sub.1-8 alkyl group, a C.sub.2-8 alkenyl group, a C.sub.2-8 alkynyl group, or a C.sub.6-12 aromatic group, and A.sup.? is hydrogen sulfite ion, dihydrogen phosphate ion, nitrate ion, halogen ion, or a combination thereof. The solvent has a chemical formula of ##STR00002##

The present invention relates to a method for preparing a nerve conduit containing cells, more particularly to a method for preparing a porous nerve conduit containing cells, having micropores formed in microchannels, wherein the nerve conduit containing cells prepared according to the present invention can be usefully used in in-vitro and in-vivo researches on nerves.