23 results about "Methyltrichlorosilane" patented technology

The invention relates to a preparation method of a low-resistance silicon carbide coating based on a molybdenum / tantalum metal electrode, which comprises the following steps: S1, substrate pretreatment: carrying out mechanical micro roughening, ultrasonic cleaning and drying on a Mo / Ta electrode, and then reducing to remove an oxidation film; s2, Si-rich nucleation: taking methyl trichlorosilane as a Si / C common source, hydrogen as carrier gas / reducing gas and nitrogen as an n-type doping source for gas supply to form a compact nucleation layer; s3, main body deposition is conducted, specifically, the temperature is adjusted to 1140-1180 DEG C, the total pressure is maintained to be 80-120 Torr, and gas supply continues to be conducted for deposition; s4, annealing and dechlorination: stopping methyl trichlorosilane, keeping hydrogen and nitrogen flushing, and then annealing; and S5, cooling and shaping: cooling and taking out the sample annealed in the step S4, and adjusting the surface roughness to a set value to obtain the low-resistance silicon carbide coating on the Mo / Ta electrode. Compared with the prior art, on the premise that conductivity is not sacrificed, atomic oxygen / oxygen ion resistance, sputtering resistance, thermal cycling stability and the like of the Mo / Ta electrode can be remarkably improved.

The invention discloses a device and a method for preparing a fiber-reinforced SiC ceramic-based composite material based on Joule thermochemical vapor infiltration. The device is specifically characterized in that a graphite clamp and a fiber preform are arranged in a reactor, a trichloromethylsilane container, a flowing protective gas introduction device and a tail gas treatment device are respectively communicated with the reactor through gas pipes, and the fiber preform is connected with an external power supply through fibers extending outwards; the preparation method comprises the following steps: putting a fiber fabric preform and a graphite clamp into a reactor, connecting the fiber preform into a circuit, heating the interior of the fiber preform, introducing methyltrichlorosilane and hydrogen into the reactor, turning off a power supply, and cooling a sample to room temperature, thereby completing the preparation. Local high temperature is formed through Joule heat, heating is conducted from the inside to the outside of the preform, SiC is deposited on the fiber preform from inside to outside, so that the material achieves high uniformity, internal pores are reduced, and the density and the deposition rate are improved.

The invention relates to a method and a system for improving SiC bulk doping yield based on retention boundary layer design, and relates to the technical field of semiconductor material preparation, chemical vapor deposition treatment is carried out on gas-phase raw materials on the surface of a substrate, and the gas-phase raw materials are gaseous methyl trichlorosilane, hydrogen, nitrogen and helium; the method comprises the following steps: collecting the flow rate and chemical vapor deposition processing parameters of a gas-phase raw material in real time, controlling the volume flow ratio of hydrogen to gaseous methyl trichlorosilane to be 3-15, and calculating the thickness of a retention boundary layer of the gas-phase raw material according to the flow rate and chemical vapor deposition processing parameters of the gas-phase raw material, the thickness of the retention boundary layer of the gas-phase raw material is compared with the preset thickness of the retention boundary layer, the flow velocity of the gas-phase raw material and / or chemical vapor deposition processing parameters are / is adjusted according to the comparison result, and the SiC block material prepared through the method is compact and free of pores or free carbon or silicon carbide nanowires, and the adjustable range of the resistivity is wide.

A method for producing a fiber-reinforced composite, is provided with: introducing a reinforcing fiber fabric into an atmosphere-controllable reaction furnace, the reinforcing fiber fabric including reinforcing fibers woven together and gaps having aspect ratios of 35 or larger between the reinforcing fibers; flowing into the reaction furnace a source gas including hydrogen and methyltrichlorosilane; and causing a reaction to create a coating of silicon carbide in the gaps by heating the reaction furnace to maintain the reinforcing fiber fabric at a temperature above 1000 degrees C. and below 1100 degrees C. with maintaining the reaction furnace at a pressure below an atmospheric pressure, whereby the coating binds the reinforcing fibers together.

This invention provides a denitrification catalyst suitable for alkali furnaces, its preparation method, and its application, comprising the following raw materials: TiO2 support, pore modifier, vanadium precursor, tungsten precursor, Ce-modified component, and La-modified component; based on the mass of the TiO2 support, the mass percentages of the pore modifier are 3-7%, the vanadium precursor is 1-3%, the tungsten precursor is 1-7%, the Ce-modified component is 1-5%, and the La-modified component is 0.5-1.5%; the pore modifier is methyltrichlorosilane. This invention uses a V-W-Ti system as its base. By modifying the pore structure of the TiO2 support, capillary condensation is eliminated, and hydrophobicity is achieved; Ce modification of the V-W-Ti system enhances the selective adsorption of oxygen vacancies and NH3; and La modification of the V-W-Ti system enhances the acidity of the catalyst and provides alkali metal sacrificial sites. These three components synergistically address the problems of water poisoning, alkali poisoning, and insufficient activity at low temperatures.

The application relates to a silicon carbide composite material preparation method based on optimization of a CVI deposition rate and a silicon carbide fiber reinforced silicon carbide composite material, which comprises silicon carbide fiber preform weaving, preform molding and drying, BN interface deposition, CVI densification and MI densification; the CVI densification takes methyltrichlorosilane as a precursor, hydrogen as a carrier gas and a reducing agent, the total supply flow rate of the hydrogen is controlled in the range of 9-11 L / min ‑1 , the reaction temperature is 1000-1300 DEG C, the system pressure is 20-25 kPa, and the deposition time is 50-80 hours. In the application, the hydrogen carrier gas flow rate in the CVI densification process is controlled in an optimization range, the phenomenon that the preform surface is prematurely sealed can be effectively avoided while sufficient precursor supply and higher deposition efficiency are ensured, the reaction gas can be fully penetrated into the preform and uniform deposition is realized, and the overall density and structural uniformity of the composite material are effectively improved.

The invention belongs to the technical field of chemical vapor deposition, and particularly relates to a method for synthesizing methylsilane to grow a 4H-SiC single crystal by using an ionic liquid catalyst, which comprises the following specific steps: step 1, taking high-purity methyltrichlorosilane (MeSiCl3) as an initial raw material, the preparation method comprises the following steps: reacting a raw material with an ionic liquid catalyst 1-ethyl-3-methylimidazole aluminum chloride [EMIM] [AlCl4] in a specific molar ratio to synthesize electronic-grade methylsilane, synthesizing the electronic-grade methylsilane by using the ionic liquid catalyst, and realizing high-efficiency and high-quality crystal growth by using an accurately controlled adsorption purification and crystal growth process. Particularly, the infrared thermometer is arranged in the HTCVD equipment, and the measurement accuracy of the infrared thermometer reaches + / -1 DEG C, so that the infrared thermometer plays a key role in monitoring the temperature control in the crystal growth process, and the uniformity and repeatability of crystal growth are ensured.

The invention provides a method for preparing methyl chlorosilane by using methyl chlorosilane high-boiling cracking residual liquid. The method comprises the following steps: by taking methyl chlorosilane high-boiling residue cracking raffinate, methyl trichlorosilane and trimethyl chlorosilane as main raw materials and Al2O3-V2O5-WO3 as a catalyst, carrying out cracking disproportionation in a high-pressure reaction kettle under the conditions of heating and pressurizing, and rectifying and separating a reaction product to obtain the dimethyl dichlorosilane. According to the method, the high-value dimethyldichlorosilane can be prepared from the hazardous waste methyl chlorosilane high-boiling cracking residual liquid through the disproportionation reaction, so that cyclic utilization of the high-boiling residue cracking residual liquid is realized, and the problems that the high-boiling residue cracking residual liquid is large in discharge amount, difficult to treat and the like are solved; and through catalysis of Al2O3-V2O5-WO3, the selectivity of dimethyldichlorosilane can be improved, toxic aniline substances carried in high-boiling residue cracking raffinate can be adsorbed, and the problems of environmental pollution and the like are solved.

The invention relates to a process for depositing a silicon carbide coating on the surface of a graphite piece, which is characterized by comprising the following steps: S1, placing the cleaned graphite piece in a deposition chamber, closing the chamber, and vacuumizing; s2, depositing a transition layer on the surface of the graphite piece, S3, introducing double precursor gases, hydrogen and argon into the deposition chamber, and depositing on the surface of the transition layer to obtain a silicon carbide layer; s4, stopping introducing the gas, carrying out heat preservation for a period of time, then bombarding the surface by using inert gas plasma for etching, and continuously carrying out heat preservation to obtain a product; the double precursor gas comprises methyl trichlorosilane and methylsilane. The method has the effect of improving the bonding strength of the silicon carbide coating and the surface of the graphite piece.

The invention provides a methyltrimethoxysilane tail gas treatment process capable of efficiently recycling raw materials and completely eradicating blockage. The invention creatively designs a'condensation-methanol spraying reaction-secondary condensation 'three-stage recovery and reaction system. Enabling tail gas to pass through a low-temperature condenser and a gas-liquid coalescer, and recovering most of liquid silane intermediates; a trace amount of methyl trichlorosilane in the residual gas phase is directionally converted into soluble alkoxy silane in a methanol spray tower under a specific temperature and pressure condition, and the soluble alkoxy silane returns to a reaction system; and finally, the tail gas is subjected to deep condensation and a gas-liquid coalescer to ensure that methanol and residual components are extremely recycled. According to the process, tail gas treatment, raw material recovery and by-product inhibition are combined for the first time, gas finally entering the absorption tower hardly contains salifying components, generation of solid particles and blockage of the absorption tower are avoided fundamentally, and great reduction of three-waste treatment cost and continuous and stable operation of production are realized.

The invention relates to a high-performance organic silicon packaging adhesive for a photovoltaic module, the packaging adhesive is an organic high-molecular compound taking a silicon-oxygen bond as a main chain, and a colloidal elastomer is formed after the packaging adhesive is cured; the working temperature range of the packaging adhesive is-55 DEG C to 250 DEG C, the light transmittance of the packaging adhesive in a visible light range is not lower than 92%, and after the packaging adhesive is aged for 1000 hours under the double-85 test conditions of 85 DEG C and 85% relative humidity, the light transmittance retention rate is larger than 95%; the packaging adhesive is prepared from a monomer mixture containing dimethyl dichlorosilane and methyl trichlorosilane through high-temperature reaction, hydrolysis and condensation processes under the action of a composite catalytic system of copper and various high polymer materials, and finally a network polymer with linear and cross-linked structures is formed. The core purpose of the invention is to provide a revolutionary photovoltaic packaging material which is high in light transmittance, extremely stable in chemical property, capable of greatly improving the reliability, the service life and the power generation efficiency of a component, and environment-friendly and recoverable.

The present invention relates to a method for preparing chlorosilanes, the method comprising the steps of: preparing a reactant comprising methylchlorosilane synthesis residue and methyldichlorosilane (MH); and reacting the reactant in the presence of an alumina catalyst to form a product comprising dimethyldichlorosilane (M2), methyltrichlorosilane (M1), and trimethylchlorosilane (M3), wherein the reaction is carried out at 300-500°C for 1-3 minutes.

This invention discloses a hydrophobic and oleophilic aerogel environmentally friendly composite material for oil-water separation, comprising: mixing and stirring a mixture of silicon tetrachloride and magnesite powder, followed by precipitation to obtain a SiO2 / MgSiO3 nano-hybrid material; immersing a melamine sponge in a hexane solution containing monomethyltrichlorosilane, then washing the sponge with ethanol and drying it to obtain a modified porous sponge; hydrolyzing the modified porous sponge in a mixture of glacial acetic acid and ethanol, then adding the SiO2 / MgSiO3 nano-hybrid material and a 10% sodium hydroxide ethanol solution to obtain a second-modified porous sponge; and finally air-drying the second-modified porous sponge in a mixture of trimethylchlorosilane and a monohydric alcohol to obtain the hydrophobic and oleophilic aerogel environmentally friendly composite material. The raw materials used in this invention are inexpensive and readily available, allowing for large-scale industrial production and filling a gap in the market for hydrophobic and oil-absorbing sponge production.

The application provides a method for catalytically cracking organosilicon high-boiling substances. The method comprises the following steps: contacting an organosilicon high-boiling substance raw material with a cracking catalyst to generate a cracking reaction; the reaction temperature of the cracking reaction is not lower than 500 DEG C; the cracking catalyst comprises a carrier and a metal active component loaded on the carrier, the metal active component at least comprises one or more of Fe, Zn, Ni, Ti and Mo, the mass content of the metal active component in the cracking catalyst is not less than 1%, the carrier at least comprises a molecular sieve, and the mass content of the carrier in the cracking catalyst is not less than 10%. The catalyst used in the cracking reaction of the application does not contain heavy metals, and has high selectivity to methyl chlorosilane monomers such as monomethyltrichlorosilane, dimethyldichlorosilane and trimethylmonochlorosilane, especially can effectively improve the selectivity of dimethyldichlorosilane, and has mild and efficient reaction conditions, high catalytic efficiency.

The invention relates to the field of organic silicon, and provides an organic silicon slurry residue recovery treatment process which comprises the following steps: S11, gas pretreatment: pretreating a mixed gas of hydrogen chloride and chlorine to obtain a prepared mixed gas, and collecting the mixed gas of hydrogen chloride and chlorine from a process of preparing white carbon black from methyl trichlorosilane; s21, leaching reaction: carrying out hydrolysis treatment on the organic silicon slurry slag to obtain copper-containing silicon slag, blending the copper-containing silicon slag and water to obtain slurry, introducing the prepared mixed gas into the slurry to carry out leaching reaction, controlling the temperature of the leaching reaction to be 60-80 DEG C and the solid content of the slurry of the leaching reaction to be 15-30%, and separating to obtain copper-containing leachate; s31, grading treatment is conducted, specifically, copper ion concentration detection is conducted on the copper-containing leachate, and grading treatment is conducted at the same time; according to the process, cooperative treatment and resource utilization of the waste gas and the slurry residues are achieved, and a copper product with the higher additional value is obtained.

The invention relates to a 2H-SiC film and a preparation method thereof.The preparation method comprises the steps that mixed gas of methyl trichlorosilane, argon and hydrogen is introduced, chemical vapor deposition is conducted on a graphite substrate, and the 2H-SiC film is formed on the surface of the graphite substrate; in the mixed gas, the conveying flow ratio of the hydrogen to the methyl trichlorosilane is greater than 15: 1. According to the preparation method, controllable adjustment of the 2H-SiC phase is achieved, the large-area 2H-SiC thin film can be prepared, meanwhile, the preparation cost is low, and commercial application of the 2H-SiC thin film can be popularized easily.

The invention relates to a method for synthesizing an alkyl acyloxy silane mixture from sodium acetate, and aims to produce a low-cost and low-crystallization-temperature cross-linking agent product for RTV (Room Temperature Vulcanization) silicone rubber. The preparation method comprises the following steps: 1) mixing and stirring alkyl acyloxy silane and sodium acetate, dropwise adding methyl trichlorosilane, supplementing sodium acetate and methyl trichlorosilane by a batch method, stirring for 1 hour without heating after dropwise adding, and then heating to react for a certain time to obtain an alkyl acyloxy silane mixture crude product; (2) further heating the reaction system, distilling out methyl trichlorosilane, a monosubstituted substance and a disubstituted substance which are not completely reacted, reacting by virtue of a tubular device filled with sodium acetate, and collecting back to the original reaction system; 3, the crude product is cooled and further filtered, and an alkyl acyloxy silane mixture product is obtained.Compared with the prior art, the synthetic route is simple, operation is convenient, the effective content of the product is high, cost is low, no organic solvent is needed, and meanwhile the difficulty that pure methyl triacetoxysilane cannot be normally used in winter is overcome.

The invention relates to a preparation method of a silicon carbide coating graphite carrier plate based on CVD (chemical vapor deposition), which comprises the following steps: S1, pretreatment of the graphite carrier plate: depositing an organic precursor on the surface of the graphite carrier plate to obtain a transition film; s2, in-situ co-deposition: introducing a composite precursor, and performing co-deposition on the surface of the transition film through chemical vapor deposition to form a silicon carbide nano-composite coating; s3, post-treatment: in the atmosphere of inert gas, cooling to room temperature along with the furnace to obtain a graphite carrier plate product with a silicon carbide coating; in the in-situ co-deposition process in the step S2, the composite precursor is methyl trichlorosilane and titanium tetrachloride. The method has the effect of improving the heat resistance of the product and the bonding strength of the coating.

A method for producing a fiber-reinforced composite, is provided with: introducing a reinforcing fiber fabric into an atmosphere-controllable reaction furnace, the reinforcing fiber fabric including reinforcing fibers woven together and gaps having aspect ratios of 35 or larger between the reinforcing fibers; flowing into the reaction furnace a source gas including hydrogen and methyltrichlorosilane; and causing a reaction to create a coating of silicon carbide within the gaps by heating the reaction furnace to maintain the reinforcing fiber fabric at a temperature above 1000 degrees C and below 1100 degrees C with maintaining the reaction furnace at a pressure below an atmospheric pressure, whereby the coating binds the reinforcing fibers together.

This application provides a low-resistivity polycrystalline silicon carbide bulk material and its preparation method and apparatus. The method involves using isostatically pressed graphite as a substrate, first loading it into a reaction mechanism and creating a sealed negative pressure environment through vacuum. Then, the furnace body is heated in sections to a set deposition temperature. Subsequently, argon, hydrogen, methyltrichlorosilane, and nitrogen are sequentially introduced to achieve the set pressure within the furnace, and deposition is carried out at this temperature to obtain a silicon carbide deposit. Finally, the gas supply is stopped, the gas inside the furnace is replaced with nitrogen, and the product is removed after controlled cooling to room temperature. Through vacuum sealing, sectioned temperature control, precise gas supply, and stable pressure deposition, the uniform distribution of reaction gases and the full progress of the reaction are effectively ensured, significantly improving the density, thickness uniformity, and compositional stability of the silicon carbide deposit. Simultaneously, stable nitrogen doping is achieved, resulting in a low-resistivity, high-purity, crack-free, and defect-free polycrystalline silicon carbide bulk material. The process offers strong controllability and good product consistency, meeting the stringent application requirements of high-end industrial fields.

The invention discloses a synthesis process for producing methyl silicone resin from methyltrimethoxysilane high-boiling residues, which comprises the following steps: adding the high-boiling residues, methylbenzene and activated carbon powder into a dissolving kettle according to a certain ratio, fully stirring and uniformly mixing, filtering the fully mixed mixture to remove insoluble substances, adding methyl trichlorosilane into a reaction kettle, stirring and reacting at the temperature of between 20 and 30 DEG C, and cooling to room temperature to obtain the methyl silicone resin. Then slowly adding the filtered mixed solution into a reaction kettle, continuously stirring and completely reacting after adding, adding methyl trichlorosilane into the completely reacted high-boiling residue reaction kettle again, uniformly stirring, and adding 20% hydrochloric acid and methylbenzene into a hydrolysis reaction kettle according to a proportion; the synthesis process for producing the methyl silicone resin from the methyltrimethoxysilane high-boiling residues has the advantages that the methyltrimethoxysilane high-boiling residues can be recycled and applied in a high-value manner, 'three wastes' are reduced, the additional value of the product is increased, and the treatment difficulty and the transportation risk of the methyltrimethoxysilane high-boiling residues are greatly reduced.

The invention discloses a preparation method of 2, 2, 4, 4-tetramethyl-1, 3-cyclobutanediol, and belongs to the technical field of organic synthesis. The method comprises the following steps: taking isobutyraldehyde as a raw material, and reacting with hydroxylamine hydrochloride in the presence of 1-butyl-3-methylimidazole chloride and a catalyst Bu4NPF6 to generate isobutyronitrile; reacting under the action of methyl trichlorosilane and methanol, and acidifying after alkaline hydrolysis to generate 2-methyl propionic acid; under the action of a dehydrating agent and triethylamine, 2, 2, 4, 4-tetramethyl-1, 3-cyclobutanedione is generated; finally, bis (2-methoxyethoxy) sodium aluminum hydride is adopted for reduction, and 2, 2, 4, 4-tetramethyl-1, 3-cyclobutanediol is obtained. The key point of the route is that 2, 2, 4, 4-tetramethyl-1, 3-cyclobutanedione is generated from 2-methylpropionic acid under the combined action of a dehydrating agent and triethylamine, and the method is simple and convenient to operate and suitable for industrial production.