When a polymer gel has excellent mechanical strength and an ability to maintain surface wetness for a longer time, the polymer gel may be very widely applied to a variety of fields. The present disclosure provides example embodiments of a polymer gel having excellent mechanical strength and an ability to maintain surface wetness for a longer time. Further, the present disclosure provides example embodiments of a method of preparing the polymer gel.

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 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 for manufacturing a crosslinked polyolefin separator and the crosslinked polyolefin separator obtained by the method are provided. The method includes (S1) mixing polyolefin, a diluting agent, an initiator and alkoxysilane containing a carbon-carbon double bonded group to an extruder, and then carrying out extrusion to obtain a silane-grafted polyolefin composition; (S2) molding and orienting the extruded silane-grafted polyolefin composition in the form of a sheet; (S3) introducing the oriented sheet to an extraction water bath containing a crosslinking catalyst to extract the diluting agent and perform aqueous crosslinking; and (S4) thermally fixing a resultant aqueous crosslinked product. The method can provide a separator having a high meltdown temperature and improved heat shrinkage.

A method for manufacturing a crosslinked polyolefin separator and the crosslinked polyolefin separator obtained by the method are provided. The method includes (S1) mixing polyolefin, a diluting agent, an initiator and alkoxysilane containing a carbon-carbon double bonded group to an extruder, and then carrying out extrusion to obtain a silane-grafted polyolefin composition; (S2) molding and orienting the extruded silane-grafted polyolefin composition in the form of a sheet; (S3) introducing the oriented sheet to an extraction water bath containing a crosslinking catalyst to extract the diluting agent and perform aqueous crosslinking; and (S4) thermally fixing a resultant aqueous crosslinked product. The method can provide a separator having a high meltdown temperature and improved heat shrinkage.

A porous polybenzimidazole (PBI) particulate resin is disclosed. This resin is easily dissolved at ambient temperatures and pressures. The resin is made by: dissolving a virgin PBI resin in a highly polar solvent; precipitating the dissolved PBI in a bath; and drying the precipitated PBI, the dried precipitated PBI being porous. The porous PBI resin may be dissolved by: mixing a porous PBI resin with a highly polar solvent at ambient temperatures and pressures to form a solution.

A porous polybenzimidazole (PBI) particulate resin is disclosed. This resin is easily dissolved at ambient temperatures and pressures. The resin is made by: dissolving a virgin PBI resin in a highly polar solvent; precipitating the dissolved PBI in a bath; and drying the precipitated PBI, the dried precipitated PBI being porous. The porous PBI resin may be dissolved by: mixing a porous PBI resin with a highly polar solvent at ambient temperatures and pressures to form a solution.

The present invention relates to: a method for producing a polyimide aerogel having low dielectric properties, high insulation, and high strength; and a polyimide aerogel prepared therefrom. The present invention has the technical gist of a method for producing a polyimide aerogel having low dielectric properties, high insulation, and high strength, and a polyimide aerogel prepared therefrom, the method including: a first step of preparing a solvent; a second step of preparing a polyamic acid resin by reacting a diamine-based monomer with an acid anhydride monomer in a solvent; a third step of preparing a polyimide resin solution by imidizing the polyamic acid resin at 150 to 200° C.; a fourth step of preparing a polyimide wet gel by mixing a crosslinking agent and an acid with the polyimide resin solution; and a fifth step of preparing a polyimide aerogel by replacing the solvent contained in the polyimide wet gel with a main substitution solvent and a minor substitution solvent and then drying, wherein, in the fifth step, the main substitution solvent and the minor substitution solvent are each added to the polyimide wet gel in a stepwise manner to produce a polyimide aerogel having the porosity of 80 to 85 vol % while forming a skeletal structure having nano-pores through solvent-exchange.

The present invention relates to: a method for producing a polyimide aerogel having low dielectric properties, high insulation, and high strength; and a polyimide aerogel prepared therefrom. The present invention has the technical gist of a method for producing a polyimide aerogel having low dielectric properties, high insulation, and high strength, and a polyimide aerogel prepared therefrom, the method including: a first step of preparing a solvent; a second step of preparing a polyamic acid resin by reacting a diamine-based monomer with an acid anhydride monomer in a solvent; a third step of preparing a polyimide resin solution by imidizing the polyamic acid resin at 150 to 200° C.; a fourth step of preparing a polyimide wet gel by mixing a crosslinking agent and an acid with the polyimide resin solution; and a fifth step of preparing a polyimide aerogel by replacing the solvent contained in the polyimide wet gel with a main substitution solvent and a minor substitution solvent and then drying, wherein, in the fifth step, the main substitution solvent and the minor substitution solvent are each added to the polyimide wet gel in a stepwise manner to produce a polyimide aerogel having the porosity of 80 to 85 vol % while forming a skeletal structure having nano-pores through solvent-exchange.

A polymer solution is created by mixing an olefin-based resin and a solvent in a pressure vessel. A high-pressure fluid of carbon dioxide is created. Temperature of the high-pressure fluid is adjusted. A mixed fluid is created by mixing the high-pressure fluid of which the temperature is adjusted and the polymer solution in the pressure vessel. Cooling of the mixed fluid causes phase separation of the mixed fluid to occur. After phase separation, pressure in the pressure vessel is released, and the solvent and the carbon dioxide vaporize. The vaporizing of the solvent and the carbon dioxide creates a porous medium of olefin-based resin.