85 results about "Cyanate" patented technology

The invention discloses a light-emitting diode packaging material and a preparation method thereof, and relates to the technical field of light-emitting diodes. The method comprises the following steps: adding 4, 4 '-diaminodiphenyl ether into pyromellitic dianhydride for condensation polymerization to obtain a polyamic acid solution, and adding zinc borate nanowires and aluminum nitride powder to prepare an inorganic skeleton enhanced polyamic acid suspension; the preparation method comprises the following steps: reacting zirconium hydroxide sol with an aluminum sec-butoxide solution, and carrying out hydrothermal reaction and high-temperature calcination to obtain ZrO2at-alpha-Al2O3 core-shell particles; the preparation method comprises the following steps: pre-polymerizing 4, 4 '-diphenylmethane bismaleimide and bisphenol A cyanate ester to obtain a prepolymer; the preparation method comprises the following steps: mixing bisphenol A type epoxy resin, inorganic skeleton reinforced polyamide acid suspension, ZrO2at-alpha-Al2O3 core-shell particles and a prepolymer under vacuum, defoaming, injecting into a mold, heating, curing, cooling and demolding to obtain the product. Through the synergistic effect of triple modification, the high temperature resistance and lasting thermal stability of the packaging material are improved, and the packaging material is suitable for the field of light emitting diode packaging with high temperature resistance requirements.

The invention relates to a method for regulating and deacidifying in a bioleaching process of low-grade copper sulphide ore, aiming at the problem of excessive acid caused by excessive oxidation of pyrite in a dump leaching system, a thiocyanate bactericide is added into the bioleaching system of the low-grade copper sulphide ore, and the thiocyanate bactericide is dissolved in a spray liquid of the bioleaching system, and is added into the spray liquid of the bioleaching system; under the catalytic action of mineral leaching microorganisms, oxidation of ferrous ions is enhanced, so that the oxidation-reduction potential of a solution is increased, oxidation of pyrite is intensified, acid accumulation is excessive, the thiocyanate bactericide can remarkably inhibit the activity of part of sulfur-oxidizing bacteria and even kill part of sulfur-oxidizing bacteria, and therefore the activity of ferrous oxide is reduced; compared with the prior art, the method has the advantages that the sulfur oxidation activity of microorganisms is greatly influenced, but the oxidation influence on iron is relatively small, so that the acid leaching is reduced under the condition that the copper leaching of the copper sulfide ore is not influenced, the copper leaching is not influenced, the acid leaching is reduced, the production cost is reduced, the environmental influence is reduced, and the like.

This invention belongs to the field of pharmaceutical chemical synthesis technology, specifically relating to a method for preparing dicyandiamide by urea pyrolysis with anti-scaling properties. The method includes a reaction process using urea, alkaline earth metal oxides, and a scale inhibitor dopant as raw materials. The scale inhibitor dopant includes at least one of silicon dioxide and titanium dioxide, and its weight accounts for 0.1% to 5% of the weight of the alkaline earth metal oxides. Experiments show that introducing a scale inhibitor dopant into the reaction system can alter the surface tension of the isocyanate melt, helping to improve the surface properties and rheological state of the intermediate melt. This reduces material adhesion and aggregation on the reactor wall, lowers the risk of scaling and clogging, and may even eliminate scale buildup on the reactor wall, thereby improving the stability of continuous production.

The application relates to the technical field of organic synthesis, and discloses a synthesis method of benzthiazuron, which comprises the following steps: step 1, addition reaction of alpha-methyl styrene and hydrogen chloride gas, and degassing to obtain a first reaction liquid; step 2, substitution reaction of the first reaction liquid and cyanate in the presence of a zinc chloride catalyst, and filtration to obtain a second reaction liquid containing isocyanate; and step 3, construction of an inorganic salt aqueous solution system with a density of 1.05-1.10 g / ml and a pH of 9-10, dropwise addition of the second reaction liquid into the system for condensation reaction with o-chlorobenzylamine, and post-treatment and refinement to obtain a target product. The non-phosgene route of chloro-isocyanate substitution is adopted, and the use of the toxic phosgene is completely avoided; the salting-out effect and interface control generated by the specific high-density salt solution effectively inhibit the isocyanate hydrolysis side reaction, and the reaction yield and product purity are obviously improved.

The invention relates to a reaction kettle for preparing bisphenol A cyanate resin, and belongs to the technical field of resin preparation, the reaction kettle comprises a resin preparation box, two groups of crushing boxes are arranged on the upper surface of the resin preparation box, and cover plates are arranged on the upper surfaces of the two groups of crushing boxes. A threaded rod and an extension rod are driven to rotate through a motor, a rotating shaft and a scraping plate C are driven to rotate under the meshing connection action of a bevel gear A and a bevel gear B, a rotating rod is driven to rotate integrally under the clamping connection action of a clamping block and a clamping groove, and solid bisphenol A cyanate monomers and solid polyphenyl ether are cut and crushed; raw materials meeting particle conditions penetrate through the filter screen frame and fall to the lower part of the crushing box, a bisphenol A cyanate monomer and polyphenyl ether are rotationally dispersed more uniformly in cooperation with the dispersion frame, and the polyphenyl ether and bisphenol A cyanate monomer melt are mixed more uniformly under the rotation action of the stirring blades and the scraper A, so that the overall mixing efficiency is effectively accelerated.

The invention belongs to the technical field of resin materials, and particularly relates to a preparation method and application of low-dielectric dual-curing resin. According to the present invention, the naphthalene ring system in the 1, 5-naphthalene diisocyanate (NDI) structure has high molecular symmetry and low polarity, and provides a low dielectric constant; hydroxypropyl acrylate (HPA) is an organic compound containing a hydroxyl group and an acrylic acid group. The preparation method comprises the following steps: reacting 1, 5-naphthalene diisocyanate with hydroxypropyl acrylate according to a molar ratio of 1: 2 to obtain photocurable naphthyl acrylate (DP) with excellent low dielectric property, mixing a monomer of the naphthyl acrylate (DP) with bisphenol E cyanate (BP) to obtain resin, and mixing the monomer of the naphthyl acrylate (DP) with the bisphenol E cyanate to obtain the low-dielectric dual-curing resin. And the dielectric material is suitable for high-speed communication, new energy electronic packaging and other application scenes with high dielectric property requirements.

The invention relates to the technical field of organic synthetic chemistry, in particular to a preparation method and medical application of selenophosphate promoted by tris (pentafluorophenyl) borane. The preparation method of the selenophosphate ester comprises the following steps: under the action of tris (pentafluorophenyl) borane, taking seleno cyanate ester and phosphate ester as reaction raw materials, and carrying out stirring reaction under a certain temperature condition to obtain the selenophosphate ester compound. The synthesis method is mild in condition, does not need a metal catalyst and an oxidizing agent, and accords with the idea of green chemistry. The method also has the advantages of simplicity in operation, few byproducts, high purity and the like. In-vitro anti-inflammatory experiments prove that the selenophosphate compound disclosed by the invention has remarkable anti-inflammatory activity, can effectively inhibit the generation of inflammatory factors and cell inflammatory response, can be used as an active ingredient of anti-inflammatory drugs, and has a wide clinical application prospect.

The invention discloses a method for evaluating seawater resistance of a cyanate ester-based composite material for a structural material, and belongs to the field of material performance testing, and the method comprises the following steps: S1, preparing a sample plate of the cyanate ester-based composite material for seawater resistance testing, and cutting the sample plate into a sample sheet I, a sample sheet II and a sample sheet III; s2, soaking the sample piece I, the sample piece II and the sample piece III, and sampling and testing at different time nodes; s3, obtaining a fitting equation about the water absorption rate, the interlayer shear strength and the glass transition temperature; s4, converting into a long-time fitting equation; s5, calculating an evaluation score; s6, comparing the evaluation score S with the required score of the allowable value of the cyanate ester matrix composite to obtain an evaluation conclusion; the evaluation score is calculated through fitting equations corresponding to the water absorption rate, the interlaminar shear strength and the glass transition temperature, and the method is used for predicting the seawater resistance of the cyanate ester matrix composite for the structural material.

The invention discloses a high-temperature-resistant epoxy molding compound for electronic packaging and a preparation method thereof, and relates to the field of electronic packaging materials. The invention aims to solve the problem that the epoxy molding compound prepared in the prior art is poor in high temperature resistance and cannot meet the higher working temperature requirement of a new generation of semiconductors. The invention discloses a high-temperature-resistant epoxy molding compound for electronic packaging. The high-temperature-resistant epoxy molding compound is prepared from the following components in percentage by mass: 10%-15% of o-cresol formaldehyde epoxy resin, 12%-18% of dicyclopentadiene cyanate ester, 0.1%-0.5% of copper acetylacetonate, 70%-80% of inorganic filler, 1%-2% of a coupling agent, 0.5%-1% of a release agent and 0.1%-0.5% of carbon black. A triazine ring structure with a high cross-linking characteristic is introduced into a resin matrix, so that the heat resistance is excellent; the prepared high-temperature-resistant epoxy molding compound for electronic packaging has the characteristics of high heat resistance, low dielectric constant, high breakdown field strength, high mechanical strength and the like, and is applied to the field of electronic packaging.

The invention discloses a method for recovering precious metals from an extracted organic phase. According to the method for recycling the precious metal from the extracted organic phase, thiourea-thiocyanate (TU-SCN-) is adopted to cooperate with a complexing back-extraction agent A to conduct multi-stage back-extraction on the extracted organic phase O, and metal recycling in the extracted organic phase is achieved. According to the method for recovering the precious metal from the extracted organic phase, a thiourea-thiocyanate (TU-SCN-) synergistic complexing back extraction system is adopted for recovering the metal from the extracted organic phase, the back extraction efficiency is high, and the metal recovery rate is high (gt; and precious metals such as gold and silver can be recovered from an organic phase at a relatively low cost.

The application belongs to the technical field of fluorocarbon surfactant application, and particularly discloses a synthesis method of sodium perfluorohexylethyl sulfonate, which comprises the following steps: (1) under the protection of nitrogen, perfluorohexylethyl iodine, potassium thiocyanate and a phase transfer catalyst are added into water and stirred to react, an organic layer is separated, and rotary evaporation is performed to obtain perfluorohexylethyl thiocyanate; (2) the perfluorohexylethyl thiocyanate is added into water and heated, and then chlorine is continuously introduced to stir to react, and filtration separation is performed to obtain perfluorohexylethyl sulfuryl chloride; and (3) the perfluorohexylethyl sulfuryl chloride is added into sodium hydroxide water solution drop by drop, and stirred to react, and after filtration, water washing, recrystallization and drying, the sodium perfluorohexylethyl sulfonate is obtained. The sodium perfluorohexylethyl sulfonate has high yield and high purity, has excellent surface activity, has excellent compounding performance with a hydrocarbon surfactant, has very good thermal stability, salt resistance and chemical stability, and meets the environmental protection requirements.

The present invention relates to a method for curing a polythiourethane transparent casting substrate, comprising the steps of: providing a first component A comprising a polythiourethane prepolymer having iso(thio)cyanate end groups, wherein the prepolymer is prepared from at least one polythiol monomer and at least one polyiso(thio)cyanate monomer, used in an amount adapted such that the molar ratio R2 of NCX groups to SH groups is in the range of 2 to 35; providing a second component B comprising at least one polythiol monomer; mixing the first and second components A and B together and filling the resulting polymerizable mixture into a molding cavity; and the weight The present invention relates to a method comprising the steps of curing a composite mixture to obtain a polythiourethane transparent substrate, wherein the prepolymer is prepared by mixing at least one polyiso(thio)cyanate monomer and at least one polythiol monomer in initial amounts such that the initial molar ratio R1 of the NCX groups / SH groups of the monomers is in the range of 0.3R2 to 0.95R2; polymerizing the mixture; and adding an additional amount of at least one polyiso(thio)cyanate monomer to the mixture such that the molar ratio of the NCX groups / SH groups of all monomers used in the preparation of the prepolymer is equal to R2, where X is O or S.

The invention discloses an epoxy insulation paste used in an ultralow temperature environment and a preparation method thereof, and belongs to the technical field of epoxy insulation paste. The epoxy insulating glue comprises a component A and a component B, the component A is prepared from the following components in parts by mass: 56 to 58 parts of epoxy resin, 17 to 19 parts of modified inorganic filler, 13 to 15 parts of organic silicon toughening agent, 3 to 4 parts of reactive diluent, 0.4 to 0.6 part of thixotropic agent and 0.3 to 0.5 part of wetting leveling agent; the component B is prepared from the following components in parts by mass: 6 to 10 parts of cyanate ester monomer, 2 to 4 parts of 4-methyl tetrahydrophthalic anhydride and 0.3 to 0.5 part of accelerant; the modified inorganic filler is hollow porous zirconium tungstate modified by a silane coupling agent; the organic silicon toughening agent is obtained by reacting triazine containing unsaturated bonds with tetramethyldisiloxane and then reacting with 1, 3-bis (3-aminopropyl)-1, 1, 3, 3-tetramethyldisiloxane and a silane ring body, and the organic silicon toughening agent is obtained by reacting triazine containing unsaturated bonds with the tetramethyldisiloxane and then reacting with the 1, 3-bis (3-aminopropyl)-1, 1, 3, 3-tetramethyldisiloxane and the silane ring body.

The utility model discloses a nickel-free gold-substituted plating layer structure with polythiocyanate pre-plated copper, which comprises a steel substrate, and a polythiocyanate pre-plated copper layer, an acid copper plating layer, a cupronickel tin plating layer, a gold-substituted plating layer and a nano polymer protective film which are sequentially prepared on the steel substrate from inside to outside. According to the nickel-free gold-substituted plating layer structure for pre-plating copper with polythiocyanate, the binding force of the plating layer is tested by a thermal shock method according to GB / T 5270-2005 Electrodeposition and Chemical Deposition Layer Adhesive Strength Test Method for Metal Cover Layer on Metal Matrix, the plating layer does not blister or fall off, the binding force meets the standard requirement, and the plating layer can be used as a plating layer for plating copper with polythiocyanate, so that the nickel-free gold-substituted plating layer structure for pre-plating copper with polythiocyanate can be used as a plating layer for plating copper. According to an acetate fog test carried out for 72 hours according to GB / T 10125-2021 Artificial Atmosphere Corrosion Test Salt Spray Test, no corrosives are generated on the surface of a plated part, and a plated layer has good corrosion resistance.

The application discloses a kind of nanocarrier of cosmetic active substance, micro-nano flow control preparation method and application, it is related to nanocarrier technology and cosmetic field.The application includes the following steps: S1, preparation of lipid phase, phospholipid and sterol are uniformly dissolved in ethanol, obtain lipid phase;S2, preparation of water phase, cyanate fruit polysaccharide and polypeptide are uniformly dissolved in distilled water, after uniform dissolution, centrifugation, take supernatant, obtain water phase;S3, preparation of nanocarrier, lipid phase and water phase are transported to the inside of micro-nano flow control chip and combined, lipid phase and water phase are combined to form nanocarrier in the inside of micro-nano flow control chip, obtain precursor solution containing nanocarrier;S4, screening nanocarrier, precursor solution is reduced pressure distillation, then centrifugal removal organic solvent and free un-wrapped component, obtain nanocarrier.Polypeptide is dissolved in water phase, can keep the active conformation of polypeptide peptide chain in larger amount, so that nanocarrier can deliver active substance to the specified structure layer of skin.

The application discloses a preparation method of sulfentrazone intermediate, which comprises the following steps: in a solvent, substitution ring-closing reaction of cis-trans isomer compound (nitro hydrazone) shown in formula II and cyanate salt is carried out to generate sulfentrazone intermediate shown in formula III. The scheme provided by the application solves the problems in the prior art, such as the use of a large amount of inorganic reducing agent, such as sodium sulfite, in the production of raw material phenylhydrazine for preparing triazolinone through phenylhydrazine, generation of a large amount of solid waste, and low atomic economy; the scheme solves the problems in the prior art, such as the use of a large amount of sulfite reducing agent and sodium hypochlorite oxidant in the production of raw material phenylhydrazine for preparing triazolinone through phenylhydrazine, generation of a large amount of mixed salt, and low chloro-substitution selectivity of sulfentrazone prepared by using phenylhydrazine as raw material; the scheme solves the problems, such as the reduction of diazonium salt to hydrazine, the oxidation of hydrazine to hydrazine, and the like; the scheme directly utilizes intermediate hydrazine and then utilizes cyanate salt ring-closing, and compared with the prior art, the scheme is shortened by 3 steps, and energy consumption and labor intensity are greatly reduced.

The invention relates to a method for preparing fenbendazole by taking m-dichlorobenzene as a raw material. The method comprises the following steps: nitrating m-dichlorobenzene to obtain 1, 3-dichloro-4-nitrobenzene; the 4-chloro-3-nitrodiphenyl sulfide reacts with thiophenol salt to obtain 4-chloro-3-nitrodiphenyl sulfide; reacting with ammonia to obtain 4-amino-3-nitrodiphenyl sulfide; reducing to obtain 3, 4-diaminodiphenyl sulfide; and finally, cyclizing with methyl cyanate to obtain benthioimidazole. The method has the advantages that cheap m-dichlorobenzene is used as a starting raw material, benzenethiol is efficiently synthesized through nitration, thiophenol substitution, ammoniation, reduction and cyclization reaction, the defect that expensive or difficult-to-obtain raw materials are used in the prior art is avoided, and the method is novel in route, simple and convenient to operate, mild in reaction condition, high in total yield and suitable for industrial production.

Compositions and methods are disclosed for improving seed quality. For example, treating a stand of seed crops with a seed crop treatment that includes an effective amount of cyanate, thiocyanate, an acceptable salt of cyanate or thiocyanate, an ester of cyanate or thiocyanate, an isocyanate or isothiocyanate, or a combination thereof results in one or more improved seed qualities compared to a control. The improved seed qualities may include, but are not limited to, enhanced seed vigor, increased quantity of saleable seed, increased proportion of saleable seed, increased uniformity of seed shape and size, and desirable bag weight.

The invention discloses a method for analyzing and extracting gold from gold-loaded resin containing base metal, and relates to the technical field of precious metal metallurgy. The method comprises the following steps: step 1, pickling and resolving metal zinc; 2, metal copper is analyzed through the agent at the normal temperature, a small amount of gold ions in analysis liquid are recycled through activated carbon, and gold mud is obtained after electrodeposition; thirdly, the gold-loaded resin is circularly washed through alkaline thiocyanate, and electrodeposition treatment is conducted on the separated gold-containing pregnant solution to obtain gold mud; 4, carrying out acid regeneration on the desorbed resin; and 5, carrying out alkali neutralization on the resin subjected to acid regeneration, and reducing the resin into OH-type resin for recycling. According to the method, the gold-loaded resin with high base metal content can be effectively analyzed, meanwhile, the electrodeposition energy consumption and the cost of electrodeposition equipment are reduced, and the analysis gold extraction time is shortened.

The invention provides a resin composition and application thereof. The resin composition comprises the following components: cyanate ester resin, bismaleimide resin, epoxy resin and nitride filler, based on the total weight of the resin composition being 100%, the content of the cyanate ester resin is 4%-17%, the content of the bismaleimide resin is 2%-12%, and the content of the epoxy resin is 3%-16%; the nitride filler comprises (A) spherical boron nitride, (B) aluminum nitride and / or silicon nitride; the content of the spherical boron nitride is 20-40% by taking the total weight of the nitride filler as 100%. The resin composition provided by the invention has high thermal conductivity, excellent adhesive property and high heat resistance at the same time, and the metal-based copper-clad laminate prepared from the resin composition has excellent comprehensive properties in the aspects of high thermal conductivity, high reliability and high heat resistance.

This invention provides a method for purifying erythromycin thiocyanate. The method first involves dissolving crude erythromycin thiocyanate in an ester solvent under alkaline conditions; then adding thiocyanate and crystallizing under neutral to slightly alkaline conditions; followed by membrane-assisted cooling for secondary crystallization; and finally, filtration and drying to obtain purified erythromycin thiocyanate. This invention uses a membrane-assisted cooling coupled crystallization method instead of the traditional cooling crystallization method, successfully controlling the nucleation rate, eliminating explosive nucleation, and significantly improving the content and yield of erythromycin thiocyanate A.

The present invention relates to curable mixtures of reactive resins having polymerizable functional cyanate groups and linear poly (bisphenol-diorganosiloxane) copolymers, to a method for the production thereof, and to cured materials and composites obtainable therefrom which exhibit high fracture resistance. The invention based on the patent application is a result of a project funded by the Federal Education Institute under the funding code 03XP0170C. The content of the patent application is responsible for the applicant.

The invention relates to the technical field of organic synthesis, and particularly discloses a method for synthesizing a 2-hydroxyl diaryl urea derivative. According to the method, benzoxazole compounds and aryl iso (thio) cyanate are used as raw materials and react in a methanol solvent at 60 DEG C under the synergistic catalysis of PIFA and protonated aluminum oxide, and an o-hydroxyl-ureido structure is constructed in one step. According to the method, highly toxic phosgene / isocyanate and noble metal catalysts are thoroughly avoided, the problems of low yield and more byproducts of a traditional route are solved, and the highest yield of 87% is achieved under normal-pressure mild conditions. 100% regioselectivity is achieved through a ring opening / coupling mechanism, derivatives containing 24 substituent groups such as halogen, trifluoromethoxy and naphthyl are successfully synthesized, and the bottleneck of asymmetric urea selective synthesis is broken through.

The application discloses a preparation method of a 7-position-hydrogen-substituted pyrazolo[1,5-a]pyrimidine compound. The preparation method comprises the following steps: contacting a compound shown in a formula (I) with a compound shown in one of formula (II) or formula (III), a thiocyanate, an iodine-containing oxidant and a solvent to react. The preparation method has the characteristics of simple operation, low cost of raw materials, wide application range of substrates and high yield, and the obtained product is an important pharmaceutical intermediate.

The invention discloses nitrous acid and ammonia nitrogen resistant nitrobacter (Nitrobacter sp.) TKz-YC01, the preservation number of the nitrous acid and ammonia nitrogen resistant nitrobacter (Nitrobacter sp.) TKz-YC01 is GDMCC No: 65729, the nitrous acid and ammonia nitrogen resistant nitrobacter (Nitrobacter sp.) TKz-YC01 has been preserved in Guangdong Microbial Culture Collection Center on March 7, 2025, is called GDMCC for short, has the preservation address of Nitrobacter sp., and is classified and named as Nitrobacter sp., and the preservation name of the nitrous acid and ammonia nitrogen resistant nitrobacter (Nitrobacter sp. TKz-YC01 is Nitrobacter sp. The nitrobacter can effectively degrade nitrite, cyanate and / or ammonium salt in water, and the nitrobacter can still effectively remove nitrogen under the impact of 30 mM ammonium salt (ammonium chloride) and 50 mM nitrite (sodium nitrite).

The invention discloses an intermediate for synthesizing 7-methylxanthine as well as a synthesis method and application of the intermediate, 4-amino-1-methylimidazole-5-carboxylic acid ethyl ester is taken as a raw material and reacts with cyanate to synthesize 4-ureido-1-methylimidazole-5-carboxylic acid ethyl ester, and finally, sodium hydroxide is used for alkali ring closing to obtain the 7-methylxanthine.

The invention discloses a metal-based isocyanate gold leaching agent and a high-temperature catalytic synthesis method thereof. The high-temperature catalytic synthesis method of the metal-based isocyanate gold leaching agent comprises the following steps: grinding and uniformly mixing a proper amount of cyanate and a metal catalyst to obtain a mixture; carrying out high-temperature roasting on the mixture to obtain a roasted product; and the roasted product is naturally cooled and crushed, and the metal-based isocyanate gold leaching agent is obtained. According to the metal-based isocyanate gold leaching agent and the high-temperature catalytic synthesis method thereof, the synthesis raw materials are simple and easy to obtain, the cost is low, the synthesis process is simple and easy to control, the production efficiency is high, the energy consumption is low, and the metal-based isocyanate gold leaching agent has excellent gold leaching performance; the method can replace sodium cyanide to realize efficient gold leaching under the original cyaniding gold leaching process and equipment.

The application discloses preparation and application of amino acid isocyanate derivative. The amino acid isocyanate derivative containing isocyanogen, carboxylate group and different side chains is prepared through esterification, neutralization, formylation, isocyanation and saponification by taking amino acid as raw material. The preparation route is simple in operation, low in raw material cost, mild in reaction condition, novel in synthesis route, high in product yield, various in product types and good in industrial conversion prospect. The prepared amino acid isocyanate derivative can be used in preparation of polyamino acid derivative or copolymer antibacterial material, so that the single type, high price and difficulty in obtaining of commercially available isocyanate is made up, the product added value is improved, the type selection of polyamino acid derivative or copolymer is expanded, and a new direction for further improving antibacterial activity is provided.

The invention relates to an anti-moisture absorption treatment method for a water-soluble mold, belongs to the technical field of water-soluble mold processing, and aims to solve the problem that a water-soluble mold for forming an annular frame of a space camera is easy to absorb moisture. The method comprises the steps that a water-soluble adhesive, a base material and water are mixed in proportion and subjected to cold press molding to form a water-soluble mold blank block, and rough machining mold blocks are obtained through drying and reserved machining allowance cutting; mixing the mold block with a cyanate ester resin block, and heating to melt the resin and form a curing layer on the surface of the mold block; and finish machining is carried out on the mold block coated with the curing layer, and demolding cloth can be coated after finish machining. Moisture absorption prevention protection of the water-soluble mold is achieved through the cyanate resin curing layer, the dimensional stability of the mold is guaranteed, and then the subsequent annular frame forming precision is guaranteed.

The invention discloses a method for preparing calcium cyanamide based on two-stage reaction of a rotary tube furnace, and relates to the technical field of inorganic chemical synthesis, and the method comprises the following steps: obtaining industrial urea and self-burning calcium oxide; the method comprises the following steps: uniformly mixing and grinding industrial urea and self-burning calcium oxide according to a mass ratio of 2: 1 to obtain a reaction precursor, and putting the reaction precursor into a rotary tube furnace; introducing high-pressure inert protective gas into the rotary tube furnace to replace air, controlling the rotary tube furnace to continuously rotate, and controlling the reaction precursor in the rotary tube furnace to react at the constant temperature of 240 DEG C for 2 hours to obtain a calcium cyanate intermediate; continuously introducing high-pressure inert protective gas into the rotary tube furnace, controlling the calcium cyanate intermediate in the rotary tube furnace to perform high-temperature reconstruction reaction for 2.0 hours at the temperature of 650 DEG C and the pressure of 2.2 MPa, and removing carbon dioxide to obtain a target calcium cyanamide product. According to the invention, a brand-new, more efficient, more environment-friendly and easier-to-industrialize calcium cyanamide production path is constructed.