摘要:
In a Rochow process, organohalosilanes are prepared by reacting metallic silicon particles with an organohalide in the presence of a copper catalyst and a co-catalyst. The invention uses as the co-catalyst a powder of co-catalyst active element-copper alloy containing substantial strain energy because this co-catalyst can reduce the activation time taken until a steady state is reached, which has been an outstanding problem in Rochow reaction, maintain the steady state over time and increase the selectivity of desired diorganodihalosilane for eventually increasing the yield based on the starting silicon.
摘要:
For the preparation of organopolysiloxanes, water glass diluted with water to a concentration of 3 to 15 wt % is reacted with a triorganohalosilane in the presence of an acid and an oxygen-containing solvent such as isobutyl alcohol, methyl isobutyl ketone or 1-pentanol. The invention achieves a considerable reduction of the environmental load, an improved utilization of reactants, an improved yield, and a cost reduction, and enables production of low viscosity MQ resins.
摘要:
A silicon oxide powder represented by the formula: SiOx wherein 1.05≦x≦1.5 and having a BET specific surface area of 5-300 m2/g is useful as a negative electrode material to construct a lithium ion secondary cell having a high capacity and improved cycle performance.
摘要翻译:由式:SiOx表示的氧化硅粉末,其中1.05 <= x <= 1.5,BET比表面积为5-300m 2 / g,可用作负极材料,以构建具有 高容量和改进的循环性能。
摘要:
Spherical, non-crystalline silica particles made by burning a non-halogenated siloxane starting material are substantially halogen-free, and have a content of metallic impurities other than silicon of not more than 1 ppm, a particle size of 10 nm to 10 &mgr;m and a specific surface area of 3-300 m2/g. Production of the particles is carried out by oxidative combustion of the non-halogenated siloxane in a flame at a high adiabatic flame temperature to effect the formation of a large number of core particles and promote their coalescence and growth.
摘要:
When oganohalosilanes are prepared by charging a reactor with a contact mass containing a metallic silicon powder, a copper catalyst and a co-catalyst, and introducing an organohalide-containing gas into the reactor to effect the direct reaction, the catalyst and/or co-catalyst used in the contact mass is obtained by mixing particles of the catalyst and/or co-catalyst with finely divided silica, and applying shear forces to the mixture for mutually rubbing the particles, thereby producing the catalyst and/or co-catalyst having finely divided silica fused to surfaces thereof. The invention is successful in producing organohalosilanes at a significantly improved formation rate without reducing the proportion of diorganodihalosilane.
摘要:
Organohalosilanes are prepared by reacting an organic halide with metallic silicon particles in the presence of a metallic copper catalyst which is a metallic copper powder in flake form having a bulk specific gravity of 1-3 g/cm3 and a mean particle size of 10 &mgr;m to 1 mm as measured by laser diffraction particle size distribution analysis.
摘要翻译:有机卤代硅烷通过在金属铜催化剂的存在下使有机卤化物与金属硅颗粒反应来制备,金属铜催化剂是片状比重为1-3g / cm 3,平均粒径为10〜 通过激光衍射粒度分布分析测量为1mm。
摘要:
Polymer scale deposition from a polymerization medium in which a monomer having an ethylenic double bond is polymerized, is prevented by conducting the polymerization in a polymerization vessel having a coating by applying a liquid comprising (A) an organic compound containing at least one member selected from the group consisting of a sulfonic acid group and a carboxylic acid group and having a molecular weight of 1000 or less and (B) a water-insoluble compound having an absorption band in the visible light range of 540 to 750 nm, the compounds (A) and (B) having been dissolved or dispersed in (C) an ester-based organic solvent, and having a pH of 3 or less; to the inner wall surfaces of said polymerization vessel. Polymer scale can be effectively prevented and polymeric products are barely colored.
摘要:
A method of preventing polymer scale deposition in a polymerization vessel in polymerization of a particular monomer having an ethylenic double bond having a high dissolving power against the conventional scale preventive coatings, wherein said polymerization is carried out in a polymerization vessel of which the inner wall has been previously coated with a first coating solution comprising:(A) a water-soluble anionic dye, and(B) at least one member selected from the group consisting of inorganic colloids and cationic dyes, to form a first coating, and the first coating thus formed has been then coated with a second coating solution comprising:(C) an alkaline earth metal compound, and at least one member selected from the group consisting of:(D) a water-soluble anionic dye and(E) an inorganic colloid, to form a second coating. The polymerization vessel having the double coating as prepared above is also disclosed. Polymer scale deposition can be effectively prevented.
摘要:
A method of preventing polymer scale deposition during polymerization of a monomer having an ethylenically double bond in a polymerization vessel, comprising the step of carrying out said polymerization in a polymerization vessel of which the inner wall surface has a coating comprising a water-soluble polysaccharide; and a polymer scale preventive agent comprising polysaccharide. By use of the method or agent, deposition of polymer scale can be effectively prevented; in addition, polymers with a high whiteness can be prepared. Moreover, the scale preventive agent used has no poisonousness or the like and is highly safe.
摘要:
Scale deposits during polymerization of monomers containing ethylene-type double bonds are prevented by coating the reactor walls and parts with cationic dyes oxidized with hydrogen peroxide.