13 results about "Trimethyl borate" patented technology

The invention discloses a synthesis method of high-purity triethyl silane, and belongs to the technical field of organosilicon compound synthesis. The method solves the problems of low purity, poor stability and serious pollution of the existing synthesis method, sodium hydride and trimethyl borate are used as starting raw materials, a trimethoxy sodium borohydride solution is generated in situ under a low-temperature condition, then the trimethoxy sodium borohydride solution and accurately metered triethyl chlorosilane are subjected to a mild and controllable reduction reaction, and the high-purity triethyl chlorosilane is obtained. According to the method, the dependence of a traditional process on a noble metal catalyst or a highly toxic reducing agent is abandoned, the reaction safety is improved from the source, the complete reaction is promoted by adopting the composite catalyst, and the hydrophobic modified 3A molecular sieve is innovatively utilized for low-temperature adsorption purification, so that key impurities such as trace moisture and chloride ions can be efficiently removed; and finally, high-vacuum precise rectification is combined, so that a high-purity triethyl silane product can be obtained.

The application provides a lithium ion electrolyte additive, a lithium ion electrolyte and a preparation method thereof, a lithium battery and an electrical equipment, and relates to the field of lithium batteries. The lithium ion electrolyte additive is 5-trifluoromethylpyridine-2-lithium trimethylborate. The preparation method comprises the following steps: mixing 2-hydroxy-5-trifluoromethylpyridine, lithium bis(trimethylsilyl)amide and a first organic solvent, and stirring and reacting to obtain 5-trifluoromethylpyridine-2-lithium hydroxide; and dropping trimethyl borate into a second organic solvent containing 5-trifluoromethylpyridine-2-lithium hydroxide, and reacting to obtain 5-trifluoromethylpyridine-2-lithium trimethylborate. The additive has a low oxidation potential, can form an effective CEI film before LNMO deintercalates lithium ions, thereby inhibiting the decomposition of the electrolyte in the subsequent reaction, reducing the generation of harmful substances HF, and further protecting the structure of the material.

The embodiment of the invention relates to the technical field of chemical devices, in particular to an esterification device and a system for manufacturing boric acid. The esterification device comprises an esterification container, a heating piece and a stirring assembly, the esterification container forms an esterification chamber and a liquid inlet, a feed port and a discharge port which are communicated with the esterification container, the liquid inlet is used for introducing a boron trifluoride-methanol complex into the esterification chamber, the feed port is used for introducing a solid defluorination agent into the esterification chamber, and the discharge port is used for discharging the boron trifluoride-methanol complex into the esterification chamber; the boron trifluoride-methanol complex and the solid defluorinating agent are subjected to an esterification reaction in the esterification chamber to generate trimethyl borate and a solid by-product; the heating piece is arranged to heat the esterification chamber and keep the temperature in the esterification chamber stable; the stirring assembly is used for stirring the materials in the esterification chamber, so that the materials are uniformly mixed. According to the esterification device, the temperature in the esterification chamber is kept constant through the heating piece, the reaction process is accelerated through the stirring assembly, and the esterification reaction rate and the material conversion rate can be increased.

The invention provides a preparation method of a mixed nitride composite material special-shaped antenna window, which belongs to the technical field of composite materials, and comprises the steps of mixed weaving, washing, pretreatment, vapor deposition, dipping curing, cracking, rough machining, finish machining and finished product obtaining. The pretreatment comprises the following steps: mixing silicon tetrachloride with absolute ethyl alcohol, stirring, adding triton X-100 and trimethyl borate, and uniformly stirring to obtain a pretreatment solution; immersing the washed antenna window prefabricated part into the pretreatment liquid, placing the washed antenna window prefabricated part into a supercritical reaction kettle, introducing carbon dioxide, heating to 38-42 DEG C, controlling the pressure to 9-12MPa, stirring for 1.5-2.5 hours, taking out, standing and drying, and keeping the temperature at 570-590 DEG C for 1.8-2.5 hours and keeping the temperature at 880-910 DEG C for 2.7-3.2 hours in an air atmosphere to obtain an initial antenna window; the prepared antenna window is high in strength, excellent in high temperature resistance and good in ablation resistance.

The invention provides a preparation method of a boron nitride fiber reinforced ceramic-based composite material, and belongs to the technical field of boron nitride fiber reinforced ceramic-based composite materials. The preparation method comprises the steps of mixed slurry preparation, fiber cloth pretreatment, coating curing and sintering. The step of preparing the mixed slurry comprises the steps of preparing silicon-boron-oxygen-nitrogen powder, coating and pulping; the preparation method of the silicon-boron-oxygen-nitrogen powder comprises the following steps: mixing tetraethoxysilane and absolute ethyl alcohol, uniformly stirring, dropwise adding trimethyl borate at a dropwise adding rate of 1-2 mL / min while maintaining a stirring speed of 480-520 r / min, adjusting the pH value to 3-4 after dropwise adding, adding hexamethyldisilazane, stirring at 40-50 DEG C for 2-3 h to obtain sol, standing, aging, drying and roasting to obtain the silicon-boron-oxygen-nitrogen powder. The silicon-boron-oxygen-nitrogen powder is obtained; the composite material prepared through the method is high in mechanical property, good in high temperature resistance and excellent in long-term service performance.

The invention relates to a continuous production process of trimethyl borate, which comprises the following steps: 1) mixing methanol and boric acid according to the molar ratio of (4.0-4.5): 1, feeding into a pre-reactor, and dissolving and pre-reacting at 64-66 DEG C; (2) continuously feeding the pre-reacted material into the middle upper part of an esterification rectifying tower, continuously carrying out esterification reaction and rectifying separation, controlling the tower top temperature at 53-55 DEG C, and extracting an azeotrope of trimethyl borate and methanol; (3) conveying a methanol-water mixed solution discharged from the bottom of the esterification rectifying tower to a methanol recovery tower, controlling the temperature of the tower top at 62-64 DEG C, directly introducing the extracted gas-phase methanol into the middle part or the lower part of the esterification rectifying tower, and discharging the total amount lt of boric acid / trimethyl borate from the tower bottom; and 0.5% of water. Compared with the prior art, the energy consumption can be saved by more than 50% under the condition of ensuring that the one-time conversion rate of boric acid is greater than or equal to 99.6%, the diameter and the height of the esterification rectifying tower are greatly reduced under the same productivity, and the equipment cost is reduced.

The invention discloses an inorganic zinc-rich primer coating composition, a coating as well as a preparation method and application of the inorganic zinc-rich primer coating composition. The inorganic zinc-rich primer coating composition comprises a first component and a second component, the first component comprises zinc powder and basalt fibers, and the second component comprises ethyl polysilicate, polyvinyl butyral, ethanol, water, hydrochloric acid, a specified solvent and trimethyl borate. According to the inorganic zinc-rich primer coating composition provided by the invention, the basalt fiber and the polyvinyl butyral are introduced to modify a traditional inorganic zinc-rich coating, so that the compactness, the corrosion resistance, the thermal conductivity and the irradiation resistance of a coating are remarkably improved, the coating is free of cracking under the dry film thickness of 150 microns, the salt spray resistance exceeds 3500 hours, and the coating has a good application prospect. And the protective paint can effectively pass LOCA (loss of coolant accident) superposition test, shows excellent decontamination performance and radiation stability, and completely meets the technical requirements of national and No.1 nuclear power plants on the protective paint.

This invention discloses a method for preparing a slow-release lithium iron phosphate cathode material, belonging to the technical field of lithium iron phosphate cathode material preparation. The method includes the following steps: S1. Introducing a doped carbon source into a lithium silicate precursor for CVD carbon coating to obtain a carbon-coated lithium replenishing agent; the doped carbon source is a carbon source and a dopant source; the carbon source is at least one of methane, acetylene, ethylene, and propylene; the dopant source is at least one of trimethyl borate, triethyl borate, triisopropyl borate, and trimethylcycloborane; S2. Sintering the lithium iron phosphate precursor slurry and the carbon-coated lithium replenishing agent to obtain a slow-release lithium iron phosphate cathode material. This invention forms a uniform carbon layer on the surface of lithium silicate using a gas-phase carbon source to obtain a slow-release lithium replenishing agent; then, it is blended with the lithium iron phosphate precursor slurry and sintered to obtain a cathode material with both high capacity and long cycle life. This cathode material exhibits excellent battery capacity and excellent cycle life, and its battery capacity is not easily decayed.

The application discloses a refrigerator material, a preparation method thereof and a refrigerator, and belongs to the technical field of refrigerator materials. The refrigerator material is prepared by mixing and extruding polystyrene granules and a covalent organic framework which has adsorbed sufficient nitrogen; the covalent organic framework which has adsorbed sufficient nitrogen is prepared by the following method: ZnCl2 and an alkali metal solution as a counterion donor are slowly added into a mixed solution of 2,3,6,7,10,11-hexahydroxytriphenyl and trimethyl borate in sequence, the mixture is uniformly dispersed, and then is transferred into a coaxial tubular open plasma reactor, and the covalent organic framework is prepared under DBD plasma conditions; after the covalent organic framework is subjected to a vacuumizing treatment by temperature rising, nitrogen is added, and a cooling treatment is conducted, so that the covalent organic framework which has adsorbed sufficient nitrogen is obtained. The application is applied to the field of refrigerator materials, solves the technical problem that existing materials cannot meet the requirements of low odor, high strength and antibacterial property of the materials for refrigerators, and has the characteristics of low odor, high strength and bacteriostasis.

The application relates to the field of filtering materials, and discloses a filter bag loaded with a denitration catalyst and a preparation method thereof, the filter bag comprising interface modifier impregnated modified polytetrafluoroethylene fibers and a catalytic additive loaded on the modified polytetrafluoroethylene fibers, the interface modifier being prepared by hydrolysis-polycondensation of tetraethyl orthosilicate, perfluorooctyl ethyl trimethyl silane, trimethyl borate and 3-(2,3-epoxypropoxy) propyl trimethyl silane; the catalytic additive is a hollow spherical catalyst carrier prepared by emulsion-induced interface assembly using polyether Pluronic F127, 1,3,5-trimethylbenzene and dopamine as raw materials and by externally introducing mesoporous silica, then precursors of cerium and manganese are loaded on the surface of the hollow spherical catalyst carrier and a titanium dioxide shell layer is coated to prepare the catalytic additive; the filter bag prepared by the application has good denitration activity, sulfur resistance, water resistance, hydrophobicity and friction resistance.

The application provides a gel polymer electrolyte and a preparation method of a secondary lithium battery. In a water and oxygen isolation environment, a pre-polymer slurry is obtained by adding a polymer monomer, a thermal initiator and one of lithium carbonate, dimethylsiloxane or trimethyl borate into an organic electrolyte; the pre-polymer slurry is coated on the surface of a porous support material, and a gel polymer electrolyte is polymerized in situ. The preparation method of the application can generate lithium difluorophosphate in the polymerization process, can reduce the interface resistance between the polymer electrolyte and the electrode, can improve the interface stability and the ion transmission efficiency, can improve the cycle and rate performance of the lithium battery, and the battery can be used in a wide temperature range of-20 DEG C to 90 DEG C. The application can generate lithium difluorophosphate in situ, which can improve the performance of the electrolyte, does not need to be added additionally, and is simple in introduction.

The application discloses high-performance boron nitride nanoceramics and a preparation method thereof, and relates to the technical field of ceramics. The preparation method comprises the following steps: S1, mixing trimethyl borate, urea and ethanol according to a molar ratio of 1:(1.2-1.5):(5-8) to obtain a mixed solution, adding nano carbon powder, stirring and reacting to obtain a transparent boron nitride precursor sol; S2, freeze-drying the boron nitride precursor sol to obtain fluffy boron nitride precursor powder; S3, heating the boron nitride precursor powder to 800-1000 DEG C under an ammonia atmosphere, and keeping the temperature for 2-3 h to obtain boron nitride nano powder; and S4, carrying out spark plasma sintering on the boron nitride nano powder to obtain high-performance boron nitride nanoceramics. Through synergistic effect of multiple steps and precise control of process parameters, the boron nitride ceramic with a grain size of 20-50 nm, high density and high thermal conductivity and excellent comprehensive performance is obtained.

This application discloses a high-performance boron nitride ceramic and its preparation method, relating to the field of special ceramic materials technology. The method includes: using trimethyl borate and urea as raw materials, adding a co-dispersion composed of bimodal carbon nanoparticles, polyethylene glycol, and α-ferric oxide nanoparticles, and obtaining a sol through a sol-gel reaction; obtaining a precursor powder by freeze-drying; performing a three-stage nitriding treatment under an ammonia atmosphere to obtain boron nitride nanoparticles; and finally obtaining boron nitride ceramic by spark plasma sintering. This method achieves rapid densification at low temperatures, resulting in ceramics with high density, high thermal conductivity, high flexural strength, and low dielectric constant. Furthermore, by controlling the α-ferric oxide content through layering, a bilayer structure of iron-rich and iron-poor layers is formed, significantly improving the fracture toughness of the ceramic.