There is provided a method of manufacturing an openly and highly porous thermoset foam, the method comprising the steps of mixing a thermosetting resin and crystals to form a mixture; applying pressure to the mixture to expel excess thermosetting resin, thereby producing a network of crystals touching each other with the thermosetting resin filling the interstices between the crystals of said network; curing the thermosetting resin in the mixture under pressure to produce a cured material; and contacting the cured material with a solvent for the crystals, thereby leaching the crystals out of the cured material, thereby obtaining said openly and highly porous thermoset foam. There is also provided a thermoset foam made of a thermoset and having a porosity of at least about 70%, wherein more than about 75% of the pores in the foam are connected to a neighboring pore.

The invention relates to the manufacturing of porous polymer membranes by (a) providing pellets comprising a polymer matrix and particles in the ratio 90:10 to 10:90, (b) converting said pellets into a non-porous film by a solvent-free process; (c) removing said particles from said film with an aqueous composition to thereby obtain said membrane. The invention further relates to pellets useful in such manufacturing process as well as porous polymer membranes obtainable or obtained by such manufacturing process as well as textile materials and articles containing such membranes; to the use of such pellets, membranes, and articles.

Provided is a filtration method that includes a cleaning step and involves the use of a porous membrane, wherein the filtration method offers exceptional resistance to cleaning solutions (chemicals) (chemical liquid resistance) and exceptional filtration performance, and has a long service life. A filtration method includes the following steps: a filtration step in which a liquid to be processed that contains a material to be filtered is passed through a porous membrane configured from a resin having a three-dimensional mesh structure, and a filtrate is separated from the material to be filtered; and a cleaning step in which the porous membrane has a cleaning solution passed therethrough or is immersed in the cleaning solution so that the interior of the porous membrane is cleaned.

Provided herein are methods for fabricating a porous polymer material, methods for revealing hidden anti-counterfeiting patterns, chromogenic sensors having hidden anti-counterfeiting patterns, and the like. Chromogenic sensors including porous polymer materials are provided. The chromogenic sensors can reveal hidden patterns such as anti-counterfeiting patterns and the pattern can be re-hidden.

A thermoplastic sulfur-polymer composite comprises a thermoplastic polymer, such as polyethylene and polystyrene; and a sulfur element. Such sulfur element functions as passive sulfur filler in this composite. The thermoplastic polymer is a polymer matrix; and the sulfur filler is dispersed in the polymer matrix. There is no chemical reaction occurs after the addition of the sulfur filler into the host polymer and no chemical bond formed between the polymer and the sulfur filler. The thermoplastic sulfur-polymer composite can be a nanocomposite by either adding certain nanofillers into the composite or making the sulfur filler as sulfur nanoparticles. With its similar physical properties and lower manufacturing costs, the thermoplastic sulfur-polymer composites are good alternatives of the respective pure polymers.

A porous, resorbable and flexible dental surgical membrane (16) is made from chitosan having a viscosity average molecular weight of about 400,000 daltons up to about 2,000,000 daltons and has a thickness of from about 100 microns to about 0.5 mm. The membrane is easily insertable over a bone graft material site to confine the bone graft material (14) while allowing access to the bone graft material of blood and oxygen and applied medicaments through the membrane. The high molecular weight of the chitosan may be chosen so that the membrane will not dissolve or resorb in a human mouth for a protracted period, e.g., from about 12 to about 16 weeks. The membrane is made by dissolving medical grade chitosan in aqueous acetic acid, dispersing fine silica particles into the solution to form a slurry, depositing a film of the slurry on a support surface, evaporating liquid from the slurry sufficiently to form a coherent chitosan membrane having silica particles dispersed therein, and then dissolving the silica particles with a sodium hydroxide solution followed by a water wash to form the porous chitosan membrane.

As a nonaqueous electrolyte secondary battery separator having a transverse direction/machine direction crease recovery angle ratio of close to 1, a nonaqueous electrolyte secondary battery separator is provided that includes a polyolefin porous film having a ratio of a 60-degree gloss in an machine direction to a 60-degree gloss in a transverse direction which ratio is not less than 1.00.

Provided are a porous film having excellent surface smoothness and a method for producing the same. The surface roughness of a porous film of polyvinylidene fluoride, polyethersulfone, polyimide and/or polyamide-imide is Ra 30,000 Å or less. The opening diameter of the porous film is preferably from 100 nm to 5000 nm. The method for producing a porous film preferably includes a step for kneading a varnish containing fine particles and at least one resin selected from the group consisting of polyvinylidene fluoride, polyether sulfone, polyamic acid, polyimide, polyamide-imide precursor, and polyamide-imide. The varnish preferably has a viscosity at 25° C. of 0.1-3 Pa.Math.s, a solids fraction concentration of 10-50 mass %, and a fine particle average particle size of 10-5000 nm.

Implantable devices for orthopedic, including spine and other uses are formed of porous reinforced polymer scaffolds. Scaffolds include a thermoplastic polymer forming a porous matrix that has continuously interconnected pores. The porosity and the size of the pores within the scaffold are selectively formed during synthesis of the composite material, and the composite material includes a plurality of reinforcement particles integrally formed within and embedded in the matrix and exposed on the pore surfaces. The reinforcement particles provide one or more of reinforcement, bioactivity, or bioresorption.

To provide a method for producing a porous film in which even when minute fine particles are used, fine particles can be satisfactorily dispersed, a method for producing a composition for producing a porous film, and a porous film that can be produced by the method for producing a porous film. When a porous film is formed using a varnish including at least one resin component selected from the group consisting of polyamide acid, polyimide, a polyamide-imide precursor, polyamide-imide and polyethersulfone, and fine particles, varnish is produced by dispersing the fine particles by using a pressure device that pressurizes slurry including the fine particles and a dispersing device provided with a flow path whose cross-sectional area is 1960 μm.sup.2 or more and 785000 μm.sup.2 or less, and allowing the slurry pressurized to 50 MPa or more to pass through the flow path.