The present invention concerns a material, based on fibrillar, elongated, or disk-like colloidal particles, that has a high scattering efficiency, a method that is suitable for preparing such a material, and the use of such a material. The material can be used as, or as a part of, a pigment, paint or protective coating in various industries, but due to its high scattering, and due to the fact that the material appears white even as a thin membrane, it is an interesting option also in the paper and pulp, cosmetic and medical industries.

The present invention relates to a process for the preparation of a polyarylethersulfone-polyalkylene oxide block copolymer (PPC) by converting a reaction mixture (R.sub.G) which comprises, among others, at least one aromatic dihalogen sulfone, at least one dihydroxy component comprising trimethylhydroquinone and at least one polyalkylene oxide. The present invention furthermore relates to a polyarylethersulfone-polyalkylene oxide block copolymer (PPC) obtainable by the inventive process and to its use in a membrane (M) and to a membrane (M) comprising the polyarylethersulfone-polyalkylene oxide block copolymer (PPC). Furthermore, the present invention relates to a method for the preparation of a membrane (M).

The present disclosure relates to synthesis of porous polymer networks and applications of such materials. The present disclosure relates to a method of fabricating of a porous polymer network comprising: (a) providing: (i) a first reactant comprising a plurality of compounds comprising at least one acetyl group, said plurality of compounds comprising at least one compound type, and (ii) a second reactant comprising an alkylsulfonic acid, and (b) creating a solution of said reactants, (c) casting said solution in a form, and (d) treating said solution under such conditions so as to produce a porous polymer network. In one embodiment, the invention relates to a porous polymer network which has a basic structure selected from the group consisting of

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The present invention relates to a hydrophilic foam material, which is of particular use in wound treatment, and to a method for producing said hydrophilic foam material. The hydrophilic foam material has nucleating particles, wherein at least 85% of all foam cells in said foam material have an average cell size of 0.01 mm.sup.2 or less.

Nanoporous three-dimensional networks of polyurethane particles, e.g., polyurethane aerogels, and methods of preparation are presented herein. Such nanoporous networks may include polyurethane particles made up of linked polyisocyanate and polyol monomers. In some cases, greater than about 95% of the linkages between the polyisocyanate monomers and the polyol monomers are urethane linkages. To prepare such networks, a mixture including polyisocyanate monomers (e.g., diisocyanates, triisocyanates), polyol monomers (diols, triols), and a solvent is provided. The polyisocyanate and polyol monomers may be aliphatic or aromatic. A polyurethane catalyst is added to the mixture causing formation of linkages between the polyisocyanate monomers and the polyol monomers. Phase separation of particles from the reaction medium can be controlled to enable formation of polyurethane networks with desirable nanomorphologies, specific surface area, and mechanical properties. Various properties of such networks of polyurethane particles (e.g., strength, stiffness, flexibility, thermal conductivity) may be tailored depending on which monomers are provided in the reaction.

A filtration filter used for filtering a liquid chemical for lithography, provided with a polyimide resin porous membrane; a filtration method including allowing a liquid chemical for lithography to pass through the filtration filter; and a production method of a purified liquid chemical product for lithography, including filtering a liquid chemical for lithography by the filtration method.

A process for forming voided latex particles is improved by combining swelling and polymerization of an outer shell into a single step. The process includes contacting multi-stage emulsion polymer particles comprising a core, at least one intermediate shell, with a swelling agent, and polymerizing an outer shell after said contacting with swelling agent wherein the core and the at least one intermediate shell are contacted with swelling agent in the presence of less than 0.5% monomer based on the weight of the multi-stage emulsion polymer particles, and substantially all of the swelling occurs during polymerization of the outer shell.

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 method of manufacturing a heat-fixing rubber roller includes: forming a rubber layer of a silicone rubber composition on an outer periphery of a metal core shaft, the composition containing water-soluble sugar powder and methylene glycol; vulcanizing the rubber layer; and eluting the sugar powder and the triethylene glycol from the vulcanized rubber layer to form a foam rubber layer.

An aerogel and process of making the aerogel is provided. The aerogel is a polyimide aerogel having polyamide cross-links formed using a triacid chloride cross-linker.