摘要:
The present invention relates to a method of preparing a high hydrophobic silica aerogel having a low tap density and a hydrophobic silica aerogel prepared thereby. The method of preparing a hydrophobic silica aerogel according to the present invention may have good productivity and economic efficiency, because preparation time is reduced by simultaneously performing surface modification and solvent substitution in a single step, and may control a degree of hydrophobicity of the prepared silica aerogel by controlling a surface modification reaction by including a step of adding ammonium hydroxide. Thus, a hydrophobic silica aerogel having excellent physical properties, such as tap density and specific surface area, as well as high hydrophobicity obtained by controlling the degree of hydrophobicity may be prepared.
摘要:
A porous metal oxide material in a flake form having a specific surface area of 110 to 3000 m2/g, an average particle diameter of 5 to 500 μm, an average thickness of 0.1 to 5 μm, and an average aspect ratio of 5 to 300; a method for producing the material which comprises applying a colloid solution containing colloidal particles of the metal oxide having a particle size of 5 to 500 nm on a substrate, drying to solidify the colloid solution, delaminating the resultant solid form the substrate, and subjecting the solid to a heat treatment; and a cosmetic, a coating composition, a resin composition, an ink and a paper sheet comprising the material. The porous metal oxide material in a flake form exhibits functions inherent in a porous material, is free problems such as the reduction of handlability due to coagulation, has a great mechanical strength, and exhibits great holding capability when used as a carrier.
摘要:
This invention is a process for making modified silica filler comprising the steps of: (A) contacting an acidic aqueous suspension of precipitated or colloidal silica, optionally in the presence of a surfactant and/or a water-miscible solvent, with a combination of (a) a functionalizing coupling agent, and (b) an organometallic hydrophobing compound in a weight ratio of (a) to (b) of at least 0.001 to 1 to form an acidic aqueous suspension of chemically treated silica filler having a pH of 2.0 or less (B) treating the acidic aqueous suspension of the chemically treated filler with an acid-neutralizing agent to increase the pH of the suspension to a range of from greater than 2.0 to 10, and (C) recovering the chemically treated filler. This invention is also modified silica filler that has a pH of from about 5.0 to 10.0, where the silica filler is made by the method of this invention. This invention is also a curable silicone elastomer composition comprising a polyorganosiloxane, the modified silica filler produced by the method of this invention, and a means of curing the polyorganosiloxane into an elastomer.
摘要:
Granules based on silicon dioxide and having the properties: Average particle size: 10 to 120 .mu.m BET surface area: 40 to 400 m.sup.2 /g Pore volume: 0.5 to 2.5 ml/g Pore size distribution: less than 5% of the total pore volume exists of pores with a diameter
摘要:
A multistage precipitation and flocculation production process is disclosed in which primary silica particles are prepared and flocculated useing an alkali metal salt solution and further silica precipitated in the presence of the salt, the pH of the mixture reduced and the silica isolated, purified carefully dried and optionally milled.
摘要:
In order to provide a filler composition for fabricating a high-performance filler achieving good productivity while preventing worsening of a working environment and production of a VOC and to provide a filler and a method for producing the filler, a filler composition of the present invention contains wet silica, a polyoxyethylene unsaturated fatty acid ester, and a sulfur-containing silane coupling agent.
摘要:
A method of making a diatomaceous earth granulate may include spray-drying a suspension including particles of diatomaceous earth, a liquid medium, and a binder, wherein inorganic solids in the suspension include at least 80 wt % diatomaceous earth. The method may further include recovering a diatomaceous earth spray-dried granulate. A granular diatomaceous earth product obtained by the method may include substantially spherical granules, each having a shell including diatomaceous earth surrounding a hollow core. The product may be used as a filter aid or in filtration.
摘要:
The invention discloses nano/micron binary structured powders for superhydrophobic, self-cleaning applications. The powders are featured by micron-scale diameter and nano-scale surface roughness. In one embodiment, the average diameter is about 1-25 μm, and the average roughness Ra is about 3-100 nm. The nano/micron binary structured powders may be made of silica, metal oxide, or combinations thereof.
摘要:
Described is an improved process for producing hydrophobic particulate inorganic oxides useful for reinforcing polymeric compositions, e.g., rubber, by using a certain amount of hydrophobizing agents in an aqueous suspension of inorganic oxide having a pH of 2.5 or less and increasing the pH of the suspension after hydrophobizing the filler.