The invention relates to a process for preparing a gelled, dried composition forming a monolithic aerogel with a heat conductivity of less than or equal to 40 mW.Math.m.sup.1.Math.K.sup.1 and derived from a resin of polyhydroxybenzene(s) and formaldehyde(s), to this aerogel composition and to the use thereof. This process comprises: a) polymerization in an aqueous solvent of said polyhydroxybenzene(s) and formaldehyde(s) in the presence of an acidic or basic catalyst, to obtain a solution based on the resin, b) gelation of the solution obtained in a) to obtain a gel of the resin, and c) drying of the gel to obtain a dried gel.

According to the invention, step a) is performed in the presence of a cationic polyelectrolyte dissolved in this solvent, and the process also comprises a step d) of heat treatment under inert gas of the dried gel obtained in step c) at temperatures of between 150 C. and 500 C. to obtain the non-pyrolyzed aerogel whose heat conductivity is substantially unchanged, even after exposure to a humid atmosphere.

The present invention is directed to a process for preparing a porous material, at least comprising the steps of providing a gel comprising a solvent (S), wherein the solvent (S) has a volume (V1), pressurizing the gel with carbon dioxide at a temperature and a pressure at which carbon dioxide solubilizes in the solvent (S) forming gas-expanded liquid (EL), wherein the gas-expanded liquid (EL) has a volume (V2) and (V2) is greater than (V1); removing supernatant liquid, and drying the gel. The present invention further is directed to the porous material obtained or obtainable according to the process as such as the use of the porous material according to the invention in particular for medical, biomedical and pharmaceutical applications or for thermal insulation.

The invention relates to a process for preparing a gelled, dried composition forming a monolithic aerogel with a heat conductivity of less than or equal to 40 mW.Math.m.sup.1.Math.K.sup.1 and derived from a resin of polyhydroxybenzene(s) and formaldehyde(s), to this aerogel composition and to the use thereof. This process comprises: a) polymerization in an aqueous solvent of said polyhydroxybenzene(s) and formaldehyde(s) in the presence of an acidic or basic catalyst, to obtain a solution based on the resin, b) gelation of the solution obtained in a) to obtain a gel of the resin, and c) drying of the gel to obtain a dried gel. According to the invention, step a) is performed in the presence of a cationic polyelectrolyte dissolved in this solvent, and the process also comprises a step d) of heat treatment under inert gas of the dried gel obtained in step c) at temperatures of between 150 C. and 500 C. to obtain the non-pyrolyzed aerogel whose heat conductivity is substantially unchanged, even after exposure to a humid atmosphere.

The present invention provides, for example, a silicone porous body having a porous structure with less cracks and a high proportion of void space as well as having a strength. The silicone porous body of the present invention includes silicon compound microporous particles, wherein the silicon compound microporous particles are chemically bonded by catalysis. For example, the abrasion resistance measured with BEMCOT is in the range from 60% to 100%, and the folding endurance measured by the MIT test is 100 times or more. The silicone porous body can be produced, for example, by forming the precursor of the silicone porous body using sol containing pulverized products of a gelled silicon compound and then chemically bonding the pulverized products contained in the precursor of the silicone porous body. The chemical bond among the pulverized products is preferably a chemical crosslinking bond among the pulverized products, for example.

A method of preparing a superabsorbent polymer having a rapid absorption rate and an improved water retention capacity by additional heat treatment while using a thermally degradable internal crosslinking agent and an encapsulated foaming agent at the same time during polymerization. A superabsorbent polymer prepared by this method is also provided, the superabsorbent polymer having a centrifuge retention capacity (CRC) of 40 g/g to 55 g/g, as measured according to EDANA method WSP 241.3, and an absorption rate of 48 sec or less, as measured by a vortex method.

The present invention provides, for example, a silicone porous body having a porous structure with less cracks and a high proportion of void space as well as having a strength. The silicone porous body of the present invention includes silicon compound microporous particles, wherein the silicon compound microporous particles are chemically bonded by catalysis. For example, the abrasion resistance measured with BEMCOT is in the range from 60% to 100%, and the folding endurance measured by the MIT test is 100 times or more. The silicone porous body can be produced, for example, by forming the precursor of the silicone porous body using sol containing pulverized products of a gelled silicon compound and then chemically bonding the pulverized products contained in the precursor of the silicone porous body. The chemical bond among the pulverized products is preferably a chemical crosslinking bond among the pulverized products, for example.

The present invention aims to provide a method for producing a porous gel-containing liquid that is inexpensive and excellent in homogeneity. The porous gel-containing liquid production method according to the present invention is a method including: a pulverization step of pulverizing a gel of a porous body, wherein the pulverization step is carried out as multi-stage pulverization including a plurality of pulverization stages.

The present invention relates to a process for preparing a porous material, at least comprising the steps of providing a mixture (I) comprising a composition (A) comprising components suitable to form an organic gel and a solvent (B), reacting the components in the composition (A) in the presence of the solvent (B) to form a gel, and drying of the gel obtained in step b), wherein the composition (A) comprises at least one compound (af) comprising phosphorous and at least one functional group which is reactive towards isocyanates. The invention further relates to the porous materials which can be obtained in this way and the use of the porous materials as thermal insulation material and in vacuum insulation panels, in particular in interior or exterior thermal insulation systems as well as in water tank or ice maker insulation systems.

The present invention relates to a process for preparing a porous material, at least comprising the steps of providing a mixture (I) comprising a composition (A) comprising components suitable to form an organic gel and a solvent (B), reacting the components in the composition (A) in the presence of the solvent (B) to form a gel, and drying of the gel obtained in step b). According to the present invention, the composition (A) comprises a catalyst system (CS) comprising a component (C1) selected from the group consisting of alkali metal and earth alkali metal salts of a saturated or unsaturated carboxylic acid and a component (C2) selected from the group consisting of ammonium salts of a saturated or unsaturated carboxylic acid and no carboxylic acid is used as a component of the catalyst system. The invention further relates to the porous materials which can be obtained in this way and the use of the porous materials as thermal insulation material and in vacuum insulation panels, in particular in interior or exterior thermal insulation systems as well as in water tank or ice maker insulation systems.

A battery separator includes a polyolefin microporous membrane having a width of 100 mm or more, and a porous layer laminated on at least one surface of the polyolefin microporous membrane. The polyolefin microporous membrane has a variation range of an F25 value in a width direction of 1 MPa or less, and the F25 value indicates a value obtained by dividing a load value measured at 25% elongation of a specimen with use of a tensile tester by a cross-sectional area of the specimen. The porous layer contains a fluorine-based resin and an inorganic particle.