330 results about "Polysilazane" patented technology

The invention provides a polysilazane green special refractory ceramic coating and a preparation method thereof, and belongs to the field of ceramic coatings. The ternary core material composed of titanium carbide, zirconium boride and silicon nitride provides high hardness, oxidation resistance, thermal shock resistance and excellent thermal stability; the silicon dioxide-aluminum oxide composite shell layer remarkably improves the oxidation resistance and reliability of the coating through the synergistic oxidation resistance and crack self-repairing function; the multi-metal oxygen cluster network endows the coating with excellent electrical conductivity, thermal conductivity and corrosion resistance; the intercalated montmorillonite enhances the crack resistance and oxidation resistance through a layered structure and embedded active ions; and the boron nitride coated vanadium carbide particles provide lubricity, oxidation resistance and wear resistance. Through collaborative optimization of multiple components, the comprehensive performance of the coating is comprehensively improved in the aspects of oxidation resistance, thermal conductivity, interface stability, high-temperature performance, mechanical performance and the like, so that the coating shows excellent long-term stability and functionality in an extreme environment.

The invention discloses a high-temperature-resistant insulated copper wire and a preparation method thereof, and belongs to the technical field of enameled insulated copper wires. The high-temperature-resistant insulated copper wire comprises a copper wire body (1) and a polysilazane mixed filler layer (2), and the polysilazane mixed filler layer (2) wraps the surface of the copper wire body (1) and is formed by mixing polysilazane and inorganic filler. According to the preparation method of the high-temperature-resistant insulated copper wire, firstly, polysilazane and inorganic filler are mixed, the surface of the copper wire body is coated with the mixed polysilazane and inorganic filler, and the organic-inorganic combined coated insulated copper wire has the advantages of being resistant to high temperature and high pressure, high in hardness and quality and uniform in coating and has high stability and reliability.

The invention discloses an optical thin film and a preparation method thereof, and relates to the technical field of optical thin films. The optical thin film comprises a base film, and a low-refractive-index layer and a high-refractive-index layer which are sequentially arranged on the surface of the base film, the high refractive index layer is prepared from TiO2, a Y2O3-CeO2 nanowire and graphene oxide; the low refractive index layer is prepared from mesoporous SiO2 aerogel, a MgF2 nanosheet and polysilazane. The preparation method of the optical thin film comprises the following steps: coating the base film with the low-refractive-index layer by a sol-gel spin-coating method, and coating the low-refractive-index layer with the high-refractive-index layer by aerosol-assisted chemical vapor deposition. The surface of the base film is sequentially coated with the low-refractive-index layer and the high-refractive-index layer, so that an antireflection effect is formed, and the surface reflectivity is reduced; the comprehensive performance of high light transmission, low reflection, bending resistance, environmental aging resistance and the like is realized.

The invention relates to the technical field of high polymer materials and preparation, and discloses a high-temperature-resistant ceramic polymer-derived ceramic precursor resin molding compound and a preparation method thereof. The high-temperature-resistant composite material is prepared from the following raw materials: 100 parts of high-molecular methyl hydrogen solid polysilazane resin, 1.0 to 5.0 parts of organic silicon plastic modifier, 30 to 40 parts of hybrid fiber, 1.0 to 5.0 parts of fiber sizing agent, 20 to 25 parts of high-temperature-resistant active filler, 10 to 15 parts of fluxing agent, 1.0 to 5.0 parts of high-temperature-resistant lubricant, 0.01 to 2.50 parts of curing agent, 0.1 to 5.0 parts of release agent and 1.2 parts of high-temperature-resistant pigment. Wherein the fiber sizing agent is one or more of epoxy resin, hexamethyldisilazane and polydopamine. The high-temperature-resistant ceramizable polymer derived ceramic precursor resin molding compound provided by the invention has good processability and relatively high ceramic yield.

The invention belongs to the technical field of nanofiltration, and provides a preparation method of a recrystallized silicon carbide-silicon carbonitride ceramic membrane. The preparation method comprises the following steps: applying a polysilazane solution to a porous substrate for the first time, and then performing first pyrolysis to obtain a pyrolysis material; and applying a polysilazane solution on the pyrolysis material for the second time, and then carrying out second pyrolysis to obtain the recrystallized silicon carbide-silicon carbonitride ceramic membrane. According to the invention, a solution containing propargyl polysilazane or organic polysilazane Durazane 1500 quick-drying resin is used as a precursor to prepare the ceramic membrane, and the ceramic membrane has the advantages of high ceramic yield, excellent high-temperature stability, high retention rate and controllable microstructure, and is suitable for separation and protection application in extreme environments.

The invention belongs to the technical field of protective coatings, and particularly relates to a modified polysilazane-based protective coating, a preparation method thereof, a protective coating and application thereof. The modified polysilazane-based protective coating provided by the invention is prepared from the following preparation raw materials in parts by mass: 5.0 to 15.0 parts of polysilazane, 1.0 to 5.0 parts of a low-surface-energy compound, 1.0 to 5.0 parts of a hydrophilic compound, 1.0 to 5.0 parts of a silane coupling agent, 0.01 to 0.1 part of an initiator and 60.0 to 80.0 parts of a dispersion medium, both the low-surface-energy compound and the hydrophilic compound contain groups for free radical polymerization reaction. A protective coating formed by the protective paint provided by the invention has good environmental adaptability, and can simultaneously realize multiple effects of friction resistance, corrosion resistance, adhesion resistance, biological fouling resistance and the like when used under harsh working conditions (air / underwater environment).

The invention discloses a high-temperature-resistant high-stripping organic silicon pressure-sensitive adhesive and a preparation method thereof, and relates to a pressure-sensitive adhesive and a preparation method thereof. The invention aims to solve the problems of insufficient temperature resistance, low peel strength and poor binding force with a base material of the existing organic silicon pressure-sensitive adhesive. According to the invention, phenyl siloxane rubber, hydroxyl-terminated polysiloxane and methyl vinyl MQ silicon resin are used as basic raw materials, and polysilazane is used as a heat-resistant modifier to carry out heat-resistant modification on the chemical structure of the pressure-sensitive adhesive; a trifunctional allyl silane monomer is added in the film preparation process, so that the crosslinking density of the system is improved, and the heat resistance of the pressure-sensitive adhesive is further improved; the bonding force between the pressure-sensitive adhesive and a polyimide substrate is improved by adding the peroxysilane coupling agent, and the use of a primer in the coating process is omitted; by adding the hydroxyl MQ silicon resin and the phosphate adhesion promoter, the bonding strength of the pressure-sensitive adhesive is improved, and the high-temperature-resistant and high-stripping organic silicon pressure-sensitive adhesive is prepared. According to the invention, the high-temperature-resistant and high-stripping organic silicon pressure-sensitive adhesive can be obtained.

Provided is a novel cross-linked polysilazane which is capable of forming a silicon-containing film having excellent crack resistance while being capable of forming a thick film. The invention relates to cross-linked polysilazane with a certain structure.

The invention relates to the technical field of coatings, and discloses a polysilazane-graphene composite electrical equipment insulating and pressure-resistant protective coating and a preparation method thereof. The flame-retardant coating is prepared from the following raw materials in parts by mass: 30 to 50 parts of polysilazane, 3 to 5 parts of telomer, 1 to 3 parts of synergist, 4 to 5 parts of modified silicon dioxide, 4 to 5 parts of modified graphene, 1.5 to 2 parts of multiwalled carbon nanotube, 0.5 to 2 parts of modified zinc oxide, 1 to 2 parts of fluorocarbon surfactant and 130 to 230 parts of tetrahydrofuran. By introducing the telomer, the adhesive force of the coating on a rusty surface is effectively improved, and the properties of high temperature resistance, insulation and pressure resistance, flame retardance, water resistance, ice condensation resistance and the like are enhanced; by introducing the synergist, the modified silicon dioxide, the modified graphene, the multi-walled carbon nanotubes and the modified zinc oxide, the protection capability is further improved. Therefore, the coating disclosed by the invention is excellent in comprehensive protection performance, can meet the long-term operation requirement of power equipment in a complex and severe environment, and is wide in application prospect.

The invention discloses a water-based poly-ceramic coating material as well as a preparation method and application thereof. The formula comprises a composite base material (40-45 parts of modified waterborne polyurethane resin and 15-20 parts of a waterborne acrylic emulsion), a synergistic curing system (10-12 parts of a blocked isocyanate curing agent and 0.8-1.2 parts of a latent organic zinc salt accelerant), an organic-inorganic reinforced phase (10-15 parts of nano silicon dioxide and 8-10 parts of polysilazane) and a functional aid. The base material and the cosolvent cooperate to make VOCs less than or equal to 30 g / L, a curing system cooperates to realize low-temperature rapid curing, organic-inorganic components cooperate to form a poly-ceramic structure, the coating is adaptive to an existing roll aluminum production line, and the problems of environmental protection, energy conservation and performance of a traditional coating are solved.

The invention relates to the technical field of aerogel composite materials, and discloses an aerogel composite fiber material and a preparation method and application thereof.The aerogel composite fiber material comprises, by weight, 15-50% of polysilazane fibers and 50-85% of a silicon dioxide aerogel matrix, the polysilazane fibers and the silicon dioxide aerogel matrix are connected through Si-O-Si chemical bonding, and an inert passivation layer is arranged at the interface of the two. The preparation method comprises the following steps: immersing the polysilazane fiber in silicon source precursor sol to carry out in-situ catalytic gelation; carrying out gas phase treatment on the obtained alcogel composite material, and forming an inert passivation layer on the surface of the fiber by utilizing a generated by-product; and carrying out normal-pressure drying on the composite material subjected to gas phase treatment. Through in-situ catalysis and interface self-passivation design, the interface bonding strength and the mechanical property of the material are remarkably enhanced, normal-pressure drying of the material is achieved through gas phase treatment, the process is simplified, and the production cost is reduced.

The invention provides a high-voltage-resistant polysilazane-based insulating material for a power battery pack of a new energy automobile and a preparation method of the high-voltage-resistant polysilazane-based insulating material, and belongs to the technical field of insulating materials. The silicon carbide microspheres are prepared through reaction of polycarbosilane and polyaniline, and through hydrothermal deposition of molybdenum disulfide and coating of organic boron, the heat-conducting property, the electrical insulating property and the flame retardant property of the silicon carbide microspheres are improved; secondly, the prepared metal organic supramolecular cage is subjected to carbon nitride modification and surface modification, so that the thermal conductivity, the interface bonding force and the dielectric property of the metal organic supramolecular cage are improved; in addition, the carbon nanotubes are subjected to acid treatment, rare earth lanthanum modification and boron nitride compounding, so that the dispersity, the thermal conductivity and the insulating property of the carbon nanotubes are remarkably improved; through the synergistic effect of all the components, the thermal performance, the electrical performance and the mechanical performance of the composite material are comprehensively optimized.

The invention relates to the technical field of ceramic materials, and discloses a nitrogen-rich Si-Zr-N precursor, a nitrogen-rich amorphous SiZrN ceramic preparation method and a nitrogen-rich Si-Zr-N. The preparation method comprises the following steps: mixing perhydropolysilazane and tetrakis (dicarboxamide) zirconium, and then carrying out low-temperature liquid ammonia crosslinking and room-temperature ammonification to obtain the nitrogen-rich Si-Zr-N precursor. According to the preparation method of the nitrogen-rich amorphous SiZrN ceramic, high-temperature ammonolysis is carried out on a nitrogen-rich Si-Zr-N precursor, and the nitrogen-rich amorphous SiZrN ceramic is obtained. According to the invention, the nitrogen content of the precursor is increased through the molecular-level structure design, so that the formation of the high-nitrogen-ratio amorphous ceramic is facilitated; the pyrolysis path can be regulated and controlled, the product structure is compact, the components are uniform, and the problem of uneven mixing or incomplete reaction in the traditional method is avoided; the precursor is high in universality, is suitable for various processing and pyrolysis modes, and has good application expansibility; the cost is controllable and the method is environment-friendly.

The invention relates to a ceramic composite diaphragm as well as a manufacturing method and application thereof. The method for manufacturing the ceramic composite diaphragm comprises the following steps: (1) mixing at least two of a rare earth oxide, a metal organic framework material and glass powder, polysilazane resin and an organic solvent to obtain precursor slurry, the polysilazane resin comprising hyperbranched polysilazane resin; (2) performing electrostatic spinning on the precursor slurry to obtain a precursor film; and (3) sequentially carrying out ultraviolet light crosslinking, plasma treatment and curing treatment on the precursor membrane to obtain the ceramic composite diaphragm.

The present invention relates to a high-strength and stable sealing material for solid oxide fuel cells and its application. The high-strength and stable sealing material for solid oxide fuel cells includes: glass powder modified by surface polysilazane and ceramic powder modified by surface polysilazane; the content of the ceramic powder modified by surface polysilazane is 5-30 wt%; the content of the glass powder modified by surface polysilazane is ≥70 wt%.

The invention belongs to the technical field of special ceramic preparation, and particularly relates to high-strength special ceramic and a preparation method thereof. The high-strength special ceramic is prepared from the following raw materials: alumina powder, quartz powder, serpentine, phosphorus slag, eucryptite, barium borate, nano yttrium trifluoride, nano hafnium boride, nano strontium zirconate, nano lanthanum titanate and polyborosilazane. According to the high-strength special ceramic disclosed by the invention, the aluminum oxide powder, the quartz powder, the serpentine and the phosphorus slag are taken as matrix raw materials, eucryptite, barium borate and yttrium trifluoride are taken as fluxing agents, and nano hafnium boride, nano strontium zirconate, nano lanthanum titanate and polyborosilazane are taken as fillers, so that the prepared special ceramic has excellent bending strength and fracture toughness.

The invention relates to a fully-degradable PLA composite material with ceramic characteristics and a preparation method thereof. The fully-degradable PLA composite material is prepared from the following raw materials in percentage by weight: 25-45% of PLA, 5-13% of PBS, 48-60% of a filling agent and the balance of a processing aid, the filler is obtained by modifying an inorganic filler through a modifier; the modifier is prepared from methyl hydrogen-containing polysilazane and a bio-based maleic anhydride graft; the bio-based maleic anhydride graft is a composition of one or more of maleic anhydride grafted poly (butylene adipate-co-terephthalate), maleic anhydride grafted polyvinyl alcohol and octenyl succinic anhydride modified starch. Through the synergistic effect of the inorganic components of the filling agent, the proportion of PLA / PBS and the modifier, the filling agent has the advantages that the filling effect is good; the material is matched with the use requirement of the ceramic flying saucer on key indexes, and all components have bio-based or degradable characteristics, so that the dual targets of'ceramic performance bionics' and'environment-friendly controllable degradation 'are achieved.

The present invention belongs to the technical field of functional films, and particularly relates to a UV-protection PVB composite film, a preparation method therefor, and the use thereof. The UV-protection PVB composite film comprises an EVA / PVB composite film formed by an EVA film and a PVB film, wherein an ultraviolet light conversion layer is provided between the EVA film and the PVB film, the EVA film contains an ultraviolet light conversion agent, the PVB film contains an ultraviolet light absorber, and the ultraviolet light conversion layer is formed by coating with a transparent ultraviolet light conversion coating, and contains the ultraviolet light conversion agent, perhydropolysilazane, α-Al2O3 and a solvent. The ultrathin inorganic ultraviolet light conversion layer is designed which uses the perhydropolysilazane as a film-forming substance and the α-Al2O3 as a dispersion aid, and therefore exhibits excellent dispersibility, transparency and durability, thus reducing the use amount of light conversion agents, improving the light conversion efficiency, and solving the problem that light conversion agents added to EVA films are difficult to disperse and thus cannot achieve effective light conversion.

The invention discloses a high-temperature-resistant and high-insulation composite material for an integrally-formed inductor and a preparation method of the high-temperature-resistant and high-insulation composite material, and relates to the technical field of composites.The composite material comprises alloy powder, an insulation material and a coating material, the surface of the alloy powder is coated with the insulation material, and the alloy powder with the surface coated with the insulation material is coated with the coating material; the insulating material is polysilazane, the coating material comprises cyanate ester resin and epoxy resin, and the technical problems that traditional organic coating is prone to decomposition, moisture absorption and aging and poor in interface bonding effect with metal alloy powder can be solved.

The invention provides an insulating high-thermal-conductivity flexible silica gel sheet and a preparation method thereof. The silica gel sheet comprises the following components in parts by weight: 1-5 parts of organic boride; 1 to 5 parts of a polysilazane compound; 1-5 parts of hydrogen-containing silicone oil; 5 to 10 parts of dimethyl silicone oil; 20 to 30 parts of vinyl silicone oil; 50-80 parts of a heat-conducting filler; 0.01 to 0.1 part of a platinum catalyst; the heat-conducting filler comprises a heat-conducting filler 1 and a heat-conducting filler 2, the heat-conducting filler 1 is selected from any one of boron nitride, aluminum oxide and magnesium oxide, and the heat-conducting filler 2 is selected from any one of graphene, silicon carbide and silicon nitride. The flexible silica gel sheet provided by the invention realizes comprehensive optimization of high heat-conducting property, excellent electrical insulating property, thermal mechanical stability and surface flatness.

The invention discloses a fluoride-free oil-proof agent for paper pulp molding and a preparation method thereof, and belongs to the technical field of paper pulp molding materials. The fluoride-free oil-proof agent is prepared from the following raw materials in parts by weight: 40 to 60 parts of long-chain alkane, 10 to 20 parts of short-chain alkane, 10 to 15 parts of film-forming agent, 5 to 10 parts of modified polysilazane, 3 to 7 parts of nano material, 1 to 3 parts of chitosan derivative, 0.1 to 3 parts of cross-linking agent, 6 to 10 parts of filler and 60 to 100 parts of solvent. Wherein the modified polysilazane is prepared by reacting polysilazane with methyltriethoxysilane and 3-halogenated propylene under the action of a catalyst and chloroplatinic acid isopropanol. The preparation method comprises the following steps: mixing long-chain alkane, short-chain alkane and a solvent, and heating to react; other components are mixed and subjected to ultrasonic treatment; and mixing the two mixtures under ultrasonic and pressure conditions. The fluoride-free oil-proof agent provided by the invention is environment-friendly and safe, has excellent oil-proof performance, and is suitable for surface treatment of paper pulp molded products.

The invention discloses a weather-resistant pearlescent pigment and a preparation method thereof. The weather-resistant pearlescent pigment comprises a pearlescent pigment of which the outer surface is coated with a protective layer, the main component of the protective layer is silicon dioxide, and the protective layer is combined with the pigment substrate in a covalent bond form; and the protective layer is formed by curing polysilazane. The invention also discloses a color coating composition containing the weather-resistant pearlescent pigment, a cured coating, and a glass panel and a photovoltaic module containing the cured coating. According to the weather-resistant pearlescent pigment, a high-hardness silicon dioxide protection layer is formed on the surface of a common pearlescent pigment, and the weather resistance of the pearlescent pigment is remarkably improved.

Described herein are coated articles comprising a fluorine-free surface modification layer. In aspects, the surface modification layer includes a partial silica-like network having a ratio of Si-O-Si bonds to Si atoms in the anti-fingerprint coating of from about 2 to about 3. Additionally or alternatively, the surface modification layer further includes an alkylsilane at the outer surface and bonded to Si-O groups in the silica-like network. The method includes evaporating a functionalized polyhedral oligomeric silsesquioxane onto the first major surface. The method includes impinging an ion beam on the first major surface. Alternatively, the method includes disposing and heating a solution including a polysilazane or a polyhedral oligomeric silsesquioxane on the first major surface. In aspects, a method includes reacting a material at the first major surface with an alkylsilane.

The invention discloses preparation of flexible multifunctional anti-radiation shielding polyester filament yarn, and relates to the technical field of polyester. A ceramic filler precursor is prepared through electrostatic spinning, and nano lignin, polysilazane and aluminum oxide are used. A precursor is pretreated before calcination, carbides are formed through hot pressing, and meanwhile, a compact and continuous physical barrier can be formed in the shielding filler by means of the continuity of fibers and the cross-linking effect between the fibers. After high-temperature pyrolysis, lignin is converted into amorphous carbon, silicon carbide and silicon nitride ceramic grains are wrapped, a filler containing Si, Al and N is formed, radiation is effectively attenuated, and the shielding effect is enhanced. In addition, through combined use of the silane coupling agent and the compatilizer, the dispersity of the filler in the polyester chips is improved, the high-content polyester master batch is prepared, and the radiation shielding performance of the polyester fiber is further enhanced.

The invention discloses low-gas-evolution and high-heat-resistance precoated sand and a preparation method thereof, and relates to the technical field of casting materials.The preparation method comprises the following steps that cast steel reclaimed sand is dried, so that the water content of the cast steel reclaimed sand is reduced to 0.1% or below; taking 1000 parts by weight of treated cast steel reclaimed sand, adding 5-10 parts by weight of a silane coupling agent, and uniformly mixing; the mixed materials are heated to 75-80 DEG C and then transferred into a sand mixer, 30-40 parts by weight of organic polysilazane resin is added, and sand mixing is conducted; adding 6-8 parts by weight of carbon nanotube powder, and mixing for 30 seconds; sequentially adding 5-7 parts by weight of vinyl silicone oil and 1.8-2.4 parts by weight of calcium stearate, and uniformly mixing to obtain a precoated sand product. According to the present invention, the novel bonding system is adopted to prepare the sand mold through the low temperature film coating process, and the prepared sand mold can generate ceramic transformation during the casting stage so as to provide characteristics of extremely low gas forming amount, extremely high heat resistance, low thermal expansion rate and excellent casting quality, and the production process has characteristics of energy saving and consumption reducing.

The present disclosure provides a polymer-derived ceramic thin film thermocouple and a preparation method thereof. The polymer-derived ceramic thin film thermocouple comprises an A electrode and a B electrode, wherein one end of the A electrode and one end of the B electrode intersect and overlap to form hot junctions, an end of the A electrode away from the hot junction and the end of the B electrode away from the hot junction are provided with solder joints. Each solder joint may be connected to a lead wire, the lead wire is configured for output a signal; the A electrode is prepared by mixing a polysilazane solution, nanocomposite powder and a xylene solution, and the nanocomposite is prepared by mixing indium oxide nanopowder, zinc oxide powder and anhydrous ethanol; the B electrode is prepared by mixing a polysilazane solution, indium oxide nanopowder, and a xylene solution.

The application belongs to the technical field of inorganic porcelain composite materials, and particularly relates to an inorganic porcelain composite material for resisting salt and nitrate and preventing moisture and a preparation method thereof. The application comprises the following steps: preparation of activated base powder; and sintering of the activated base powder. The application is prepared by sintering a blank body made of calcium carbonate, talcum powder, silicon nitride, quartz sand and perhydrogen polysilazane. The perhydrogen polysilazane is first decomposed to solidify and shrink the blank body. When the temperature continues to rise, the quartz in the blank body and the silicon dioxide generated by the oxidation of the silicon nitride are both in a molten state and are fused with each other. The oxygen in the air penetrates into the blank body by diffusion and reacts with the silicon nitride. At this time, the nitrogen gas generated by the silicon nitride cannot diffuse outward under the molten blank body formed after solidification and shrinkage, and gradually gathers to cause the expansion of the base and a high closed porosity. The prepared inorganic porcelain composite material has excellent moisture resistance and high resistance to salt and nitrate.

The invention relates to the field of nuclear cable manufacturing, in particular to a radiation-resistant cable for a nuclear power platform and a preparation method of the radiation-resistant cable. According to the nuclear cable, the five-layer structural design of conductor-insulation-shielding-polyimide film-sheath is adopted, the overlapping wrapping technology of the polyimide film is combined, and the comprehensive performance of the cable in the extreme environment of a nuclear power platform is comprehensively improved. The low-smoke halogen-free flame-retardant ethylene-propylene rubber is adopted as an insulating material, and through the cooperation of an EPDM / POE blending system and the ternary composite flame retardant, the insulating property is stable under the condition of ensuring radiation, and the flame retardant property is excellent. The sheath material is added with the intumescent flame retardant and the polysilazane modifier, so that the cable has no crack at the low temperature of-40 DEG C, the bending radius can be controlled to be less than 5 times of the outer diameter, and the cable is adaptive to the layout of a narrow cabin. Through the synergistic effect of material innovation and structural design, the balance of flame retardant property, mechanical property, radiation resistance, low temperature resistance, aging resistance and small-space applicability of the nuclear cable is realized.

The invention discloses a method for preparing polysilazane nanospheres using the imgabs0 method, comprising: (1) mixing deionized water, anhydrous ethanol, and ammonia to obtain solution A; (2) using anhydrous ethanol as a solvent, dissolving silazane oligomers in anhydrous ethanol to form a solution B having a concentration of 0.01-0.04 mol / L; (3) rapidly adding solution B to solution A, and performing a sealing reaction; (4) adjusting the stirring speed to 500-550 rpm after reacting for 1-2 min, and reacting for 20-24 h; (5) stopping the reaction, filtering the reaction solution and centrifuging it, and then placing the resulting solid in a vacuum drying oven and drying it for 10-12 h to obtain polysilazane nanospheres. The present invention uses the imgabs1 method to prepare nanospheres without using any template during the preparation process, and the operating steps are simple, reducing costs, and preparing polysilazane nanospheres with good dispersion.

The invention discloses a silicon nitride aerogel compounded high-temperature-resistant rigid heat-insulation tile and a preparation method thereof, and belongs to the technical field of heat-insulation tile preparation, and the method comprises the following steps: adding a dispersing agent into pretreated high-temperature-resistant fibers, uniformly dispersing, carrying out vacuum filtration, drying, uniformly mixing with deionized water, pouring into a mold, and freeze-drying to obtain the high-temperature-resistant rigid heat-insulation tile. Carrying out carbon deposition treatment in carbon source gas to deposit pyrolytic carbon on the surface of the green body to obtain a dry green body of the heat insulation tile; and uniformly mixing polysilazane, ferrocene and xylene to obtain a polysilazane precursor solution, and injecting the polysilazane precursor solution into the heat insulation tile dry blank for heat treatment to obtain the silicon nitride aerogel compounded high-temperature-resistant light rigid heat insulation tile. The material has the advantages of strong mechanics, excellent heat insulation, high temperature resistance, oxidation resistance, balanced comprehensive performance, low density and small porosity, and is suitable for the fields of spaceflight, high-temperature equipment and the like. The strength and nucleation are improved by constructing a multi-stage structure and pyrolytic carbon, a binder-free process is green, aerogel is compounded and insulated, and the process is controllable and easy to scale.