摘要:
An aqueous dispersion containing pyrogenically prepared metal oxide particles and dispersants An aqueous dispersion containing pyrogenically prepared oxide particles of titanium, zinc, iron or cerium with an average particle size, expressed as the median, in the dispersion of less than 250 nm, that the particle sizes of the oxide particles in the dispersion are not distributed symmetrically and the dispersion contains, as a dispersant, at least one compound of the formula (I) and/or a maleic anhydride/acrylate copolymer of the general formula (IIa) and/or a maleate/acrylate copolymer of the general formula (IIb). It is prepared by dispersing a predispersion stream by means of a high energy mill. It can be used in sunscreen formulations.
摘要:
An aqueous dispersion containing a cerium oxide-doped, pyrogenically produced silicon dioxide, wherein the cerium oxide is introduced through an aerosol of a cerium salt solution or suspension and the average particle size in the dispersion is less than 100 nm. The dispersion is produced by dispersing the cerium oxide-doped, pyrogenically produced silicon dioxide in aqueous solution by means of a high energy input. The aqueous dispersion can be used for chemical-mechanical polishing.
摘要:
The preparation of high-purity organosilicon disulphanes in which, in a two-stage process, elemental sulphur and an anhydrous alkali sulphide in a deficient amount is first reacted with a halogen alkylalkoxysilane, and the sulphur deficit is then made up by the addition of further alkali sulphide.
摘要:
Aluminum oxide dispersion, which is stable in a pH range 5 from 5 to 9 and has an aluminum oxide content of at least 40 wt. %, obtainable by dispersing pyrogenically produced aluminum oxide particles in an aqueous phase, wherein one or several at least dibasic hydroxycarboxylic acids present dissolved in the dispersion and at least one salt of a 10 dialkali metal hydrogen phosphate and/or alkali metal dihydrogen phosphate are added to the aqueous phase each mutually independently in a quantity of 0.3−3×10−6 mol/m2 of aluminum oxide specific surface area.
摘要翻译:氧化铝分散体,其在5至9的pH范围内稳定,并且具有至少40重量%的氧化铝含量。 通过将热解产生的氧化铝颗粒分散在水相中可获得的,其中加入溶解在分散体中的一种或几种至少二元羟基羧酸和至少一种10碱式金属磷酸氢盐和/或碱金属磷酸二氢盐的盐 相对于水相,各自相互独立地为0.3-3×10 -6 mol / m 2的氧化铝比表面积。
摘要:
Stable, pourable silicon dioxide dispersion, in which the average, number-related aggregate diameter of the silicon dioxide particles in dispersion is less than 200 nm, and which comprises at least 35 wt. % of a silicon dioxide powder, 3 to 35 wt. % of at least one polyol, 20 to 60 wt. % of water, 0 to 10 wt. % of an additive and a substance having an alkaline action in an amount such that a pH of 10
摘要:
Process for preparing an alkaline dispersion of aggregated silicon dioxide particles by dividing a preliminary dispersion within a pH of 3 to 5 into at least two streams, placing these streams under a pressure of at least 50 bar and depressurizing them to a collision point, each via one nozzle, in a grinding chamber, and admixing the dispersion that runs off at the bottom, while still in the grinding chamber, with an alkaline substance in an amount such that the dispersion overall has a pH of more than 7.
摘要:
Stable, pourable silicon dioxide dispersion, in which the average, number-related aggregate diameter of the silicon dioxide particles in dispersion is less than 200 nm, and which comprises at least 35 wt. % of a silicon dioxide powder, 3 to 35 wt. % of at least one polyol, 20 to 60 wt. % of water, 0 to 10 wt. % of an additive and a substance having an alkaline action in an amount such that a pH of 10
摘要:
Dispersion containing aluminium oxide and water, wherein the aluminium oxide is present in the form of aggregated primary particles with a BET surface area of 20 to 200 m2/g and has a mean, volume-based aggregate diameter in the dispersion of less than 100 nm, is modified with organophosphonic acids and/or salts thereof, wherein the surface is completely or partially modified, the organophosphonic acids bear at least one amino and/or hydroxy group and is present in a content of 20 to 70 wt. %, based on the total quantity of the dispersion. Preparation containing this dispersion and a melamine resin. Cured product obtainable from the preparation. Use of the dispersion, of the preparation or of the cured product for the preparation of laminates.
摘要:
Aqueous dispersion which comprises hydrophobized silicon dioxide powder with a content of between 5 and 50 wt. % and which comprises at least one compound of the general formula R & supl; —COO—(CH2-CH(Ph)—O)a-(CnH2n-xR2xO)b-R3 (I). It is prepared by dispersing the hydrophobic silicon dioxide powder, dispersing agent and optionally pH-regulating substances and further additives in an aqueous medium. It can be employed as an additive to waterborne fillers in the automobile industry, as a coating constituent in can and coil coating processes, as an additive in water-based UV-curable formulations e.g. for wood preservation and as a constituent of protective lacquer films.
摘要翻译:水分散体,其包含含量为5至50重量%的疏水化二氧化硅粉末。 %,并且其包含至少一种通式R 1和R 2的化合物; -COO-(CH 2 -CH(Ph)-O)a - (C n H 2n-x R 2 x O)b -R 3(I)。 通过将疏水性二氧化硅粉末,分散剂和任选的pH调节物质和其它添加剂分散在水性介质中来制备。 它可以用作汽车工业中的水性填料的添加剂,作为罐和线圈涂布方法中的涂料组分,作为水基紫外线固化型配方中的添加剂。 用于木材保护和作为保护漆膜的组成部分。
摘要:
Aqueous dispersion containing pyrogenically produced oxide particles of titanium, zinc, iron or cerium having an average particle size, expressed as a median value, in the dispersion of less than 200 nm, the particle sizes of the oxide particles are not distributed symmetrically in the dispersion, the dispersion contains as dispersing agent at least one (poly)phosphate corresponding to the general formula I and has a pH of 4.5 to 7.5. It is prepared by dispersing a stream of a preliminary dispersion by means of a high-energy mill. It can be used in sunscreen formulations.