摘要:
Surface-modified zinc-silicon oxide particles which consist of a core, a first coating layer surrounding the core, and a second coating layer surrounding the first coating layer, where the core is crystalline and consists of aggregated zinc oxide primary particles having a primary particle diameter of from 10 to 75 nm, the first coating layer consists of one or more compounds containing the elements Zn, Si and O, the second coating layer comprises linear and/or branched alkylsilyl groups having 1 to 20 carbon atoms bonded chemically to the first coating layer, which have an average aggregate area of less than 40 000 nm2 and an average aggregate diameter (ECD) of less than 300 nm, a carbon content of from 0.4 to 1.5% by weight and a BET surface area of from 10 to 60 m2/g.
摘要:
Process for preparing a mixed metal oxide powder, in which oxidizable starting materials are evaporated and oxidized, the reaction mixture is cooled after the reaction and the pulverulent solids are removed from gaseous substances, wherein as starting materials, at least one pulverulent metal and at least one metal compound, the metal and the metal component of the metal compound being different and the proportion of metal being at least 80% by weight based on the sum of metal and metal component from metal compound, together with one or more combustion gases, are fed to an evaporation zone of a reactor, where metal and metal compound are evaporated completely under nonoxidizing conditions, subsequently, the mixture flowing out of the evaporation zone is reacted in the oxidation zone of this reactor with a stream of a supplied oxygen-containing gas whose oxygen content is at least sufficient to oxidize the starting materials and combustion gases completely.
摘要:
The invention relates to plastics composite mouldings obtainable via welding in an alternating electromagnetic field, in which the weld is obtained with the aid of a plastics material which comprises nano-scale, magnetic oxidic particles, which are composed of aggregated primary particles, and where the primary particles are composed of magnetic metal oxide domains whose diameter is from 2 to 100 nm in a non-magnetic metal oxide matrix or non-magnetic metalloid oxide matrix.
摘要:
Pyrogenic, oxidic particles contain superparamagnetic metal oxide domains with a diameter of 3 to 20 nm in a non-magnetic metal or non-metal oxide matrix. The particles display a chloride content of 50 to 1000 ppm. The particles are produced by pyrogenic processes by mixing the precursor of the superparamagnetic domains and the precursor of the non-magnetic metal or non-metal oxide matrix in a flame with air and/or oxygen and fuel gas and reacting this mixture in a flame. The particles can be used as ferro fluids, for example.
摘要:
Surface-modified superparamagnetic oxidic particles, characterized by the following physicochemical characteristics: BET surface area 20 to 75 m2/g; Carbon content 0.5 to 6.0% by weight; Tamped density 150 to 500 g/l; Chlorine content 50 to 1000 ppm; Drying loss 0.1 to 4.0% by weight are prepared by contacting the oxides with the surface modifier either by spraying or vapour deposition and then heat-treating them. The surface-modified oxidic particles can be used as a filler in adhesives. Further fields of application are use for data carriers, as a contrast agent in imaging processes, for biochemical separation and analysis processes, for medical applications, as an abrasive, as a catalyst or as a catalyst support, as a thickener, for thermal insulation, as a dispersing assistant, as a flow assistant and in ferrofluids.
摘要:
Process for preparing a metal oxide powder, in which starting materials are evaporated and oxidized, wherein a metal melt in the form of droplets and one or more combustion gases are fed to the evaporation zone of a reactor, where the metal melt is evaporated completely under nonoxidizing conditions, subsequently, the mixture flowing out of the evaporation zone is reacted in the oxidation zone of this reactor with a stream of a supplied oxygen-containing gas whose oxygen content is at least sufficient to oxidize the metal and the combustion gases completely.
摘要:
Formulation comprising a polymerizable monomer and/or a polymer and, dispersed therein, a superparamagnetic powder, which comprises aggregated primary particles, the primary particles being built up from magnetic metal oxide domains having a diameter of from 2 to 100 nm in a nonmagnetic metal oxide or metalloid oxide matrix. Process for heating the formulation in a magnetic or electromagnetic alternating field. Use of the formulation as an adhesive composition.
摘要:
Indium-tin mixed oxide powder which consists of primary particle aggregates and contains 50 to 90% by weight indium oxide, calculated as In2O3, and 10 to 50% by weight tin oxide, calculated as SnO2. It is produced by atomising a solution of an inorganic indium compound and an organic tin compound and burning it in a flame. It may be used for the production of electrically conductive paints and coatings, solar cells and IR and UV absorbers and in medical technology.
摘要翻译:铟 - 锡混合氧化物粉末,其由一次粒子聚集体组成,并且包含以In 2 O 3计算的50至90重量%的氧化铟和以氧化锡计为10至50重量%的氧化锡。 它是通过将无机铟化合物和有机锡化合物的溶液雾化并在火焰中燃烧而制备的。 它可用于生产导电涂料和涂料,太阳能电池和IR和UV吸收剂以及医疗技术。
摘要:
Pyrogenically prepared zinc oxide powder having a BET surface area of from 10 to 200 m2/g, which is in the form of aggregates, the aggregates being composed of particles having different morphologies, and 0-10% of the aggregates being in a circular form, 30-50% being in an ellipsoidal form, 30-50% being in a linear form and 20-30% being in a branched form. It is prepared by reacting a starting mixture containing zinc vapour, a combustible gas and steam or a mixture of steam and carbon dioxide in a flame with an oxygen-containing gas in an oxidation zone, cooling the hot reaction mixture in a quenching zone and separating the solid material from the gas stream, the amount of oxygen in the oxidation zone being greater than the amount necessary for the complete oxidation of the combustible gas and the zinc vapour. The zinc oxide powder can be used as a constituent of sun protection compositions for protection against UV radiation.
摘要:
Pyrogenically prepared zinc oxide powder having a BET surface area of from 10 to 200 m2/g, which is in the form of aggregates, the aggregates being composed of particles having different morphologies, and 0-10% of the aggregates being in a circular form, 30-50% being in an ellipsoidal form, 30-50% being in a linear form and 20-30% being in a branched form. It is prepared by reacting a starting mixture containing zinc vapour, a combustible gas and steam or a mixture of steam and carbon dioxide in a flame with an oxygen-containing gas in an oxidation zone, cooling the hot reaction mixture in a quenching zone and separating the solid material from the gas stream, the amount of oxygen in the oxidation zone being greater than the amount necessary for the complete oxidation of the combustible gas and the zinc vapour. The zinc oxide powder can be used as a constituent of sun protection compositions for protection against UV radiation.