107 results about "Dichlorosilane" patented technology

The invention provides a preparation device and process of electronic-grade silane. According to the preparation device, a first disproportionation reaction is carried out on the basis of the first reactor, dichlorosilane is rectified and separated to serve as a raw material for a second disproportionation reaction, silane can be obtained on the basis of cheap trichlorosilane and a catalytic reagent, and electronic-grade silane can be obtained on the basis of traditional purification after rectification; based on heat exchange between tower top materials of the rectifying tower I and a tower kettle reboiler of the rectifying tower II, differential pressure thermal coupling integration is realized, condensing equipment and operation steps can be omitted, energy consumption is reduced, and the defects of high preparation cost and high energy consumption of a silane preparation device in the prior art are overcome.

The utility model discloses a device for removing impurities in trichlorosilane, relates to the technical field of polycrystalline silicon production, and mainly aims to improve the removal efficiency of the impurities in the trichlorosilane on the basis of not increasing the cost. According to the main technical scheme, the device for removing the impurities in the trichlorosilane is characterized in that an inlet of a first mixer is connected to one end of a first feeding pipe and a second feeding pipe, a plurality of baffle plates are arranged in a reaction tank in a staggered mode and used for forming a baffle channel in the reaction tank, and one end of the baffle channel is connected to an outlet of the first mixer; the other end of the baffling channel, the filter and an inlet of the separating tower are sequentially connected, the inlet of the separating tower is further connected to a siloxane conveying pipe, a tower kettle of the separating tower is connected to the other end of the first feeding pipe and used for guiding siloxane to the first mixer, and a top collecting pipe of the separating tower is connected to the rectifying unit; wherein the second feeding pipe is used for guiding a trichlorosilane and dichlorosilane mixture containing impurities to the first mixer.

The invention discloses a system for purifying trimethylsilane containing dichlorosilane impurities, which comprises a reactive distillation column and a purification distillation column, and also discloses a method for purifying trimethylsilane containing dichlorosilane impurities, which comprises the following steps of: feeding trimethylsilane gas containing dichlorosilane impurities into the reactive distillation column; trimethylsilane gas containing dichlorosilane impurities enters the reaction section to react, the dichlorosilane impurities react to generate silane gas and a material containing tetrachlorosilane impurities, the silane gas is discharged from an exhaust port in the top of the reactive distillation tower, and the material containing tetrachlorosilane impurities enters the purification distillation tower from a discharge port in the bottom of the reactive distillation tower; according to the method disclosed by the invention, dichlorosilane is taken as a raw material, the dichlorosilane is taken as a raw material, the dichlorosilane is rectified in a purification rectifying tower and is collected at a tower top collecting port to obtain the high-purity trimethylsilane, the dichlorosilane impurity in the trimethylsilane can be effectively removed through the method disclosed by the invention, the high-purity trimethylsilane with the purity of 99.99% or above is obtained, the yield is greater than 85%, the process is simple, and the cost is low.

The invention relates to the field of copper-clad plates, and discloses a high-performance flame-retardant low-dielectric-loss copper-clad plate and a preparation method thereof.The copper-clad plate comprises epoxy resin, benzoxazine resin, composite filler, carboxyl-terminated nitrile rubber, an active diluent, a curing agent and the like; the composite filler is prepared by compounding flame-retardant modifier grafted graphene oxide and epoxy silane modified silicon dioxide hollow spheres; according to the flame-retardant modifier, boric acid and pentaerythritol are used for preparing a double-terminal hydroxyl boron-containing intermediate, then dichlorodiphenyl silane and phenylphosphonic dichloride react with hydroxyl groups at the two ends of the intermediate to prepare a flame-retardant intermediate, and amino silane and vanillic aldehyde react with chlorine atoms at the two ends of the intermediate to prepare an aldehyde modified flame-retardant intermediate; the copper-clad plate prepared by the preparation method disclosed by the invention is low in dielectric constant and dielectric loss, high in heat conductivity coefficient and good in flexibility, and also has excellent heat resistance and flame retardance.

The invention discloses a preparation method of diiodosilane, and belongs to the technical field of material synthesis. The preparation method of diiodosilane comprises the following steps: adding a first iodine source and a second iodine source into a closed reactor in an inert gas atmosphere, and dissolving the first iodine source and the second iodine source in a solvent to form a uniform solution; and reducing the temperature, and adding liquid dichlorosilane. Raising the temperature to 30 to 80 DEG C and reacting; and after the reaction is finished, heating at reduced pressure, rectifying and purifying to obtain the high-purity electronic-grade diiodosilane. The first iodine source is lithium iodide, the second iodine source is at least one of sodium iodide or potassium iodide, and the solvent comprises at least one of acetonitrile, acetone, diethyl ether or ethanol. Lithium iodide and sodium iodide or potassium iodide are compounded, a specific solvent is matched, and a one-step method is used for testing, so that the input cost of raw materials is reduced, the experimental steps are simplified, the reaction rate of a reaction system can be improved, and the purity of a diiodosilane product is improved.

The invention discloses a silicon nitride thin film deposition method and vertical LPCVD equipment. The method comprises the steps that S1, the standby temperature of a process cavity is set; s2, the wafer boat rises to a process position at a constant speed, and nitrogen is introduced between the inner pipe and the outer pipe; s3, closing the nitrogen, and vacuumizing the cavity; s4, introducing nitrogen into the cavity, and keeping the pressure in the cavity at P3; s5, evacuating the nitrogen in the cavity, and introducing ammonia gas; s6, under the condition that only ammonia gas flows, the pressure in the cavity is kept at P4; s7, introducing dichlorosilane into the cavity, and carrying out silicon nitride film deposition; s8, closing the dichlorosilane, keeping the ammonia gas flow unchanged, and consuming residual dichlorosilane; s9, removing ammonia gas; and S10, the process cavity recovers to normal pressure, the wafer boat descends at a constant speed, and nitrogen is introduced between the inner pipe and the outer pipe. The method has the characteristics of simple principle, high film forming stability, low pollution degree and the like, and overcomes the defect that the surface of the existing silicon nitride film is easily polluted by particles.

The invention relates to a method for preparing industrial silicon powder for organic silicon monomer synthesis from high-calcium industrial silicon melt, and belongs to the technical field of industrial silicon production. Based on the practical problems that the content of CaSi2 in an industrial silicon product is high due to the fact that the content of Ca impurities in the melt is too high after the silicon melt is subjected to external refining, and the selectivity of dimethyldichlorosilane is low when the industrial silicon is used as a raw material to synthesize an organic silicon monomer, the method comprises the following steps: obtaining the content of main metal impurities in the high-calcium silicon melt after the silicon melt is subjected to external refining; the preparation method comprises the following steps: quantitatively adding an alloying agent Al to adjust the components of a silicon melt, carrying out heat preservation and refining, pouring, and controlling the solidification rate of the silicon melt, so that a large amount of beneficial Si8Al6Fe4Ca and Si2Al2Ca phases are formed, and meanwhile, the precipitation of a harmful inclusion phase CaSi2 is avoided, and the industrial silicon powder for synthesizing the organic silicon monomer is prepared, so that the selectivity and activity of the synthesis process of the organic silicon monomer are improved.

The invention relates to the field of protective films, and discloses a liquid crystal display light guide plate TPE protective film and a preparation method thereof, the protective film comprises modified SBS, polypropylene, modified nano calcium carbonate, a lubricant and a plasticizer; the modified nano calcium carbonate is prepared by grafting a modified additive on the surface of nano calcium carbonate through chemical reaction and then coordinating with copper ions; the modified additive is prepared by preparing a chlorinated silicon-containing intermediate by using dichlorodiphenyl silane, diethylene glycol and cyanuric chloride as raw materials and then grafting a component I and 3-aminopropyltrimethoxysilane; the component I is prepared from 5-chloromethylthiazole and p-phenylenediamine through a reaction, and the modified SBS is prepared from epoxidized SBS and nano titanium dioxide subjected to amination modification by 3-aminopropyltriethoxysilane through a ring-opening reaction. The film material is endowed with excellent tensile strength, aging resistance and antibacterial and flame-retardant effects.

The invention relates to a preparation method and application of trifluoropropyl methyl cyclotrisiloxane (D3F), and the method comprises the following steps: hydrolyzing trifluoropropyl methyl dichlorosilane to prepare a hydrolysate containing D3F, and then separating and purifying through distillation to obtain a high-purity D3F product. And the D3F yield is improved by optimizing hydrolysis conditions including reaction temperature, reaction time, reaction media, the feeding ratio of a substrate to the media and the like. According to the method, D3F is directionally prepared through one-step reaction, hydrochloric acid, an organic solvent and other catalysts do not need to be additionally added into a reaction system, further catalytic cracking is not needed, and the method has the advantages of being easy and convenient to operate, high in efficiency, green in reaction condition, high in product purity and the like.

The utility model discloses an energy-saving rectification system for electronic-grade silane gas production. The energy-saving rectification system comprises a stripping tower condenser arranged on a stripping tower, and a trichlorosilane evaporator connected with a trichlorosilane tower, the trichlorosilane tower is respectively connected with a stripping tower reboiler arranged on the stripping tower and a dichlorosilane reboiler arranged on the dichlorosilane tower, the trichlorosilane tower is connected with a trichlorosilane return tank through a trichlorosilane air cooler, and the trichlorosilane return tank is respectively connected with the trichlorosilane tower and the dichlorosilane tower; the dichlorosilane tower is provided with a dichlorosilane air cooler, the dichlorosilane air cooler is connected with a dichlorosilane return tank, and the dichlorosilane return tank is respectively connected to the dichlorosilane tower and the second reactor feeding preheater; a discharge preheater of the first reactor is connected to a trichlorosilane tower, a discharge port of the second reactor is connected with a silane tower, and the silane tower is respectively connected with a dichlorosilane tower and a post-stripping tower. Therefore, efficient production of the electronic-grade silane gas is realized.

The invention provides a high-heat-resistance copper-clad plate and a preparation process thereof, and belongs to the technical field of copper-clad plates. The preparation process comprises the following steps: pretreating the polyimide film; preparing a mixed glue solution; preparing a prepreg; and hot-pressing and curing. The preparation method comprises the following steps: carrying out a reaction on m-diacetylene benzene, methyl phenyl dichlorosilane and the like used as raw materials to prepare a silicon-containing resin, and carrying out a reaction on isosorbide bis (terephthalate), bisphenol A and dibenzoate used as raw materials under the catalysis of 4-dimethylaminopyridine to prepare a modifier. When the modifier is used for modifying the silicon-containing resin to prepare the modified silicon-containing resin, as the modifier can improve the thermal conductivity of the silicon-containing resin, facilitate uniform distribution of heat and further improve the heat resistance of the silicon-containing resin, after the modified silicon-containing resin is added into a modified glue solution, the heat resistance of the modified glue solution can be effectively improved, and the service life of the modified glue solution is prolonged. Therefore, the effect of improving the heat resistance of the copper-clad plate is achieved.

The invention provides a photovoltaic glass surface self-cleaning coating and a preparation method thereof.The photovoltaic glass surface self-cleaning coating is prepared from a dehydrated organic solvent, 1-7 parts by mass of tetramethyl orthosilicate, 2-15 parts by mass of fluorosilane hydrophobic coupling agent, 10-20 parts by mass of silicon tetrachloride, 1-10 parts by mass of hydrophobic silane coupling agent, 5-15 parts by mass of dichloro (methyl) (3, 3, 5-trimethyl-1, 3, 5-trimethyl-1, 3, 5-trimethyl-1, 3, 5-trimethyl-1, 3, 5-trimethyl-1, 3, 5-trimethyl-1, 3, 5-trimethyl-1, 3, 5-trimethyl-1, 3, 5-trimethyl-1, 3, 5- and 1-10 parts of 2, 3, 3-trifluoropropyl) silane and 1-10 parts of dimethyl dichlorosilane. According to the preparation method, tetramethyl silicate with relatively low reaction activity is used as a raw material to react with silicon tetrachloride to form an intermediate species with moderate activity, and then a linear chain polymer modification layer is pre-formed on the surface by utilizing the difference of reaction rates; a fluorosilane substance added in the coating also can participate in the reaction to form an organic silicon linear polymer with a fluorosilane side chain; in the recombination process of polysiloxane, perfluoro side chains with lower surface energy migrate to the surface of the coating; meanwhile, by adding the dichlorosilane coupling agent and the trichlorosilane coupling agent, the flexibility and hydrophobicity of the coating are improved.

This invention provides a weather-resistant metal protective coating and its preparation method. The weather-resistant metal protective coating comprises a modified epoxy resin, modified carbon nanotubes, a curing agent, an initiator, and a diluent. The modified epoxy resin is prepared by reacting epoxy resin sequentially with methyldodecyl dichlorosilane and hydroxyethyl methacrylate ethyl phosphate. The modified carbon nanotubes are prepared by reacting carboxylated carbon nanotubes with 3-(methacryloyloxy)propyltrimethoxysilane. The weather-resistant metal protective coating prepared by this invention exhibits excellent anti-corrosion, anti-aging, and mechanical properties.

The carbon dioxide fire extinguishing system comprises the dichlorosilane gas holder, and a plurality of groups of carbon dioxide fire extinguishers are arranged on the left side of the interior of the dichlorosilane gas holder. The temperature monitor is used for monitoring the temperature in the dichlorosilane gas holder in real time, carbon dioxide is adopted as a fire extinguishing agent, fire disasters are rapidly and effectively extinguished, the whole process is automatic, equipment does not need to be manually started, and in a closed space, the situation that greater loss is caused by the fire disasters caused by dichlorosilane gas is effectively avoided, and the safety of the equipment is improved. The mode that a traditional fire extinguisher is manually used is changed, the situation that the fire extinguisher is hurt due to manual use is avoided, by arranging the opening and closing mechanism, workers can conveniently open the dichlorosilane gas holder and take out the carbon dioxide fire extinguisher from the dichlorosilane gas holder, and convenience and rapidness are achieved; and fire extinguishing can be carried out on any height and position of the dichlorosilane gas holder, no dead angle area exists, and the practicability is wide.

The invention discloses a method for depositing a coating on a quartz boat to solve the problem of high points on the back side of polycrystalline. The method uses a low-pressure chemical vapor deposition method of a vertical LPCVD furnace to deposit silicon nitride under the conditions of a deposition temperature of 600-800°C, an ammonia (NH3) flow rate of 100-500 SCCM, a dichlorosilane (DCS) of 20-100 SCCM, a deposition pressure of 0.1-1 Torr, and a deposition rate of 10-30 angstroms / min. When depositing silicon nitride, a monitoring piece is simultaneously loaded on the quartz boat. The monitoring piece is subjected to a silicon nitride deposition process for a duration of greater than or equal to 100 minutes. The monitoring piece is deposited to a certain thickness of greater than or equal to 2000 angstroms. The method can solve the problem of high points on the back side of polycrystalline silicon wafers. The method can replace silicon carbide boats and break through the problem of the ban on the purchase of foreign silicon carbide boats in China.

The invention discloses a trichlorosilane deep rectification composite impurity removal process, and belongs to the technical field of polycrystalline silicon production raw material purification. According to the process, deep purification of crude trichlorosilane is achieved through the steps of pre-protection and primary adsorption, directional rectification enrichment of methyl dichlorosilane narrow fractions, concentration, mixing with silicon tetrachloride, catalytic reaction rectification conversion, differential pressure thermal coupling rectification purification, double-tank parallel deep purification, tail gas treatment and the like. According to the method, the impurity methyl dichlorosilane difficult to remove is precisely separated through side extraction, the impurity methyl dichlorosilane is converted into a component easy to separate through a catalytic reaction, and the boron and phosphorus impurities are deeply removed in combination with differential pressure thermal coupling energy saving and double-tank alternate adsorption. The process can efficiently remove moisture, metals and key impurities boron and phosphorus, obviously improves the purity of the trichlorosilane product, realizes gradient utilization of energy and hydrogen circulation, and has the advantages of high purity, low energy consumption and continuous production.

The application discloses a trimethylsilane purification system containing dichlorosilane impurities, comprising a reaction rectifying tower and a purification rectifying tower, and discloses a trimethylsilane purification method containing dichlorosilane impurities. Trimethylsilane gas containing dichlorosilane impurities enters the reaction rectifying tower, and the trimethylsilane gas containing dichlorosilane impurities enters a reaction section to react. Dichlorosilane impurities react to generate silane gas and material containing tetrachlorosilane impurities. The silane gas is discharged from a tower top exhaust port of the reaction rectifying tower, and the material containing tetrachlorosilane impurities is discharged from a tower bottom discharge port of the reaction rectifying tower and enters the purification rectifying tower. The high-purity trimethylsilane is collected in a tower top collecting port through rectification in the purification rectifying tower. The dichlorosilane impurities in the trimethylsilane can be effectively removed through the method disclosed by the application, high-purity trimethylsilane with a purity of more than 99.99% is obtained, the yield is greater than 85%, and the process is simple and low in cost.

The invention discloses a method for improving the stability of a thin film in a semiconductor device. In order to solve the problems of poor quality of a first oxide layer and unstable thickness of a silicon nitride layer in the prior art, the invention provides the following steps: when forming the first oxide layer on a substrate, depositing at least part of the first oxide layer, and then performing annealing treatment based on N2O-containing gas on the first oxide layer; forming a silicon nitride layer on the annealed first oxide layer; and finally, forming a second oxide layer on the silicon nitride layer. The key N2O annealing treatment not only can densify the first oxide layer, reduce defects and improve the quality of the first oxide layer, but also can effectively consume the dichlorosilane precursor remaining on the surface of the wafer, and guarantees the stability of a silicon source during the subsequent growth of the silicon nitride layer, thereby remarkably improving the thickness stability of the silicon nitride layer. The method improves the stability of the whole thin film structure, and facilitates the improvement of the performance and reliability of the device.

The present disclosure relates to methods of forming silicon-on-insulator substrates. A method of forming an SOI substrate includes performing a hydrogen thermal treatment on a pretreated sacrificial wafer at an elevated temperature. A stop layer and a semiconductor layer can be sequentially formed on a first surface of the sacrificial wafer on which the hydrogen (H2) thermal treatment was performed. The stop layer and the semiconductor layer can be formed by an epitaxial growth process using a hybrid precursor including monosilane (MS) and dichlorosilane (DCS) sources.

A method of forming an SOI substrate including a hydrogen thermal treatment performed on a pretreated sacrificial wafer, under high temperature. A stopper layer and a semiconductor layer may be sequentially formed on a first surface of the sacrificial wafer on which the hydrogen (H2) thermal treatment was performed. The stopper layer and the semiconductor layer may be formed by an epitaxial growth process using a mixed precursor including a monosilane (MS) source and a dichlorosilane (DCS) source.

The invention provides a novel furnace tube LPCVD (Low Pressure Chemical Vapor Deposition) film forming mode for improving uniformity, which comprises the following steps: S1, placing a silicon wafer in a vertical cylindrical tray, and placing the vertical cylindrical tray in a deposition chamber of LPCVD equipment; s2, dichlorosilane (DCS) and ammonia gas (NH3) are introduced into the deposition chamber to serve as precursor gas; s3, heating the deposition chamber to 750 DEG C, and keeping the temperature for 5 minutes to start the growth of the SiN film; and S4, reducing the temperature of the deposition chamber from 750 DEG C to 720 DEG C at a rate of 5 DEG C per minute so as to ensure that the temperature of the edge of the silicon wafer is reduced faster than that of the central region. According to the novel furnace tube LPCVD film forming mode for improving the uniformity, circulation of high-temperature deposition, rapid cooling and slow heating is repeatedly carried out in the deposition process, so that the deposition rate of the edge and the center area of a silicon wafer is effectively balanced, the uniformity of the thickness of a thin film is remarkably improved, and the uniformity of the thin film is improved. And the problem of non-uniform thickness in the traditional method is solved.

The invention provides a preparation method of a modified binder, which comprises the following steps: firstly, synthesizing dimethyl silicon polyvinyl ester by taking polyvinyl alcohol and dimethyl dichlorosilane as raw materials, and then adding the synthesized dimethyl silicon polyvinyl ester into an organic binder for compounding to obtain the modified binder. The modified binder has higher heat resistance, flame retardance and waterproofness, can be applied to scenes with higher performance requirements on the binder, especially some scenes in which a welding technology cannot be used, such as underwater repair, an oil bin of a transport ship, a natural gas bin and the like, and the repair cost is reduced; the method can be used for a pipeline system and simplifies the repair process. The preparation method of the modified binder is green, environment-friendly and low in cost.

The invention provides an experimental device and method for adsorbing and removing carbon-containing impurities in trichlorosilane. The experimental device comprises a nitrogen cylinder, a dryer, a feeding tank, an intermediate tank, a mass flow controller, an adsorption column, a sampler, a storage tank and a tail gas processor. After moisture of nitrogen is removed through a dryer, the nitrogen is used for pressurizing the device, a material in the feeding tank flows through an adsorption column through an intermediate tank under the action of pressure difference, methyl dichlorosilane in trichlorosilane is adsorbed and removed, the trichlorosilane is intermittently sampled from a sampler for analysis, and the remaining material enters a storage tank; the tail gas is emptied after being treated by the tail gas treater. According to the device, the methyl dichlorosilane can be adsorbed, meanwhile, materials are prevented from being in contact with moisture in air, more reliable experimental data are provided for industrial application, and corrosion to the device is reduced.

The application discloses a hydroxyl-terminated silicon oil containing fluorine and boron and a preparation method thereof, relates to the technical field of high polymer material preparation, and is prepared from dichlorosilane compounds, (3,3,3-trifluoropropyl) dichloromethylsilane and boron-containing acid through a hydrolysis-condensation method. The hydroxyl-terminated silicon oil containing fluorine and boron has a 5% weight loss temperature of 420-440 DEG C under N2 atmosphere and a glass transition temperature of -130 DEG C to -140 DEG C, and has a wide use temperature and can be applied in many extreme occasions.

An on-line moisture detection device for dimethyl dichlorosilane hydrolysis hydrogen chloride comprises a gas conveying pipeline, a cooler, a dryer and a compressor are sequentially arranged on the gas conveying pipeline in the conveying direction, a gas inlet branch pipe is arranged on the gas conveying pipeline between the cooler and the dryer and connected to a moisture detection mechanism, and the moisture detection mechanism is connected with the compressor. And the gas conveying pipeline between the dryer and the compressor is provided with another gas inlet branch pipe, and the gas inlet branch pipe is connected to another moisture detection mechanism. By adopting the structure, the moisture content of the product hydrogen chloride can be monitored and processed in real time, the moisture content in the product hydrogen chloride is effectively controlled, and the compressor is prevented from being damaged.

The invention belongs to the technical field of organic synthesis, and provides a synthesis method of diiodosilane. The synthesis method is carried out in a first reactor and a second reactor which are connected in series, and comprises the following steps: adding a first metal chloride, a solvent, dichlorosilane (DCS) and iodobenzene into the first reactor, and carrying out a pre-reaction; after the pre-reaction, continuously introducing a solvent, dichlorosilane and iodobenzene into the first reactor; meanwhile, enabling the pre-reaction feed liquid in the first reactor to continuously flow into a second reactor filled with a second metal chloride; the first reactor and the second reactor simultaneously react; and when the volume of the reaction material liquid in the second reactor reaches a target liquid level, continuously extracting and collecting the reaction material liquid in the second reactor to realize continuous preparation of diiodosilane. The synthesis method provided by the invention is high in dichlorosilane conversion rate.

The invention relates to a preparation method of diisopropylamine silane, which comprises the following steps: (1) reacting dichlorosilane with diisopropylamine to obtain diisopropylamine chlorosilane; and (2) carrying out a reaction on the diisopropylamine chlorosilane obtained in the step (1) and lithium hydride to obtain the diisopropylamine silane. The preparation method of diisopropylamine silane in the prior art is optimized, a complex catalyst does not need to be prepared in advance, raw materials are simple and easy to obtain, reaction steps are simple, high-temperature and high-pressure reaction conditions are avoided, the reaction conditions are mild, the obtained target product has high yield and purity, and industrial large-scale production is facilitated.

The invention belongs to the technical field of ceramic precursors, and particularly relates to a silicon-boron-carbon-nitrogen ceramic precursor with a main chain containing alkynyl and a preparation method of the silicon-boron-carbon-nitrogen ceramic precursor. Comprising the following steps: (1) dropwise adding an n-butyllithium solution into an ether solvent, stirring, continuously dropwise adding trichloroethylene, and reacting to obtain an alkynyl dilithium salt turbid solution; (2) adding boron trichloride into the alkynyl dilithium salt turbid solution to carry out primary dechlorination polycondensation reaction, and dropwise adding dichlorosilane to carry out secondary dechlorination polycondensation reaction after the reaction is completed; (3) adding hexamethyldisilazane into the system in the step (2) to carry out an end-capping reaction, collecting supernate after the reaction is finished, and distilling at normal pressure to remove the solvent, so as to obtain a silicon-boron-carbon-nitrogen ceramic precursor crude product; and (4) dissolving the silicon-boron-carbon-nitrogen ceramic precursor crude product in an organic solvent, carrying out dialysis treatment, and carrying out atmospheric distillation on the solution in a dialysis membrane to remove the solvent so as to obtain the silicon-boron-carbon-nitrogen ceramic precursor with the main chain containing alkynyl, and the ceramic yield of the silicon-boron-carbon-nitrogen ceramic precursor in the high-temperature ceramization process can reach more than 70%.

This invention relates to the field of metallocene linear low-density polyethylene (MDPE) preparation technology, and particularly to a method for preparing long-chain branched metallocene polyethylene. The method comprises the following steps: A polymerization reaction is carried out in a high-pressure stainless steel reactor. A metallocene catalyst is added to the reactor with dried alkane, followed by ethylene, comonomers, and hydrogen gas, which is then introduced into the reactor. A mixed solution of dichlorosilane-functionalized non-conjugated α,ω-dienes and white oil is then added to the reactor. After stabilizing the reaction for 12-72 hours, excess steam is introduced for hydrolysis. The mixture is stirred for 1-4 hours and then discharged to obtain long-chain branched metallocene polyethylene. This invention achieves controlled molecular structure with controlled long-chain branching content, resulting in a product with high branching degree, suitable branch length, and uniform distribution. This increases the number of branched active sites and their uniform distribution, leading to excellent mechanical properties and low haze.

The utility model provides a device for producing silane, monochlorosilane and dichlorosilane at the same time. The device comprises a first reactor, a second reactor, a trichlorosilane first separation tower, a trichlorosilane second separation tower, a silane crude separation tower, a silane rectification tower, a silane purification tower, a dichlorosilane buffer tank, a dichlorosilane delivery pump, a booster pump, a monochlorine / dichlorosilane crude separation tower, a dichlorosilane purification tower and a monochlorosilane purification tower. The trichlorosilane first separation tower / the trichlorosilane second separation tower is used for recovering trichlorosilane in circulating material flow, a booster pump is arranged at the bottom of the trichlorosilane first separation tower, and due to the fact that different rectification pressures are adopted and the two towers are coupled for heat exchange, energy consumption of the whole system is reduced; the operation is flexible and convenient; and the product at the bottom of the silane coarse separation tower is circulated to the trichlorosilane first separation tower for cyclic utilization, so that the utilization rate of by-products is improved, and the cost is saved.