301 results about "Formate" patented technology

The invention discloses a synthesis method of 2-bromomethyl-5-trifluoromethyl furan, which comprises the following steps: S1, carrying out reaction on acetoacetate and halogenated trifluoroacetone under the action of an alkaline substance and a catalyst to generate a 2-acetyl-5, 5, 5-trifluoro-4-oxovalerate crude product; s2, carrying out a cyclization reaction on the 2-acetyl-5, 5, 5-trifluoro-4-oxovalerate crude product, so as to obtain a 2-methyl-5-(trifluoromethyl) furan-3-formate crude product, and carrying out a cyclization reaction on the 2-acetyl-5, 5, 5-trifluoro-4-oxovalerate crude product to obtain a 2-methyl-5-(trifluoromethyl) furan-3-formate crude product; s3, adding an alkaline substance into the crude product, carrying out hydrolysis, and adding acid to adjust the pH value after the hydrolysis is completed, so as to obtain 2-methyl-5-(trifluoromethyl) furan-3-formic acid; s4, the 2-methyl-5-(trifluoromethyl) furan-3-formic acid is subjected to a heating decarboxylation reaction, and 2-methyl-5-(trifluoromethyl) furan is obtained; and S5, carrying out a bromination reaction on the 2-methyl-5-(trifluoromethyl) furan and a bromination reagent to obtain a final product 2-bromomethyl-5-(trifluoromethyl) furan. The raw materials used in the synthesis method are easy to obtain, use of control chemicals is not involved, and industrialization is easy to achieve.

The invention belongs to the field of fertilizers, and particularly relates to a foliar fertilizer with high amino acid synthesis efficiency and a preparation method thereof.The preparation method comprises the steps that spermidine is taken to be subjected to formic acid esterification modification, and formic acid esterification spermidine is obtained; the preparation method comprises the following steps: hydrolyzing 2, 4-epibrassinolide to obtain carboxylated brassinolide; under the action of Tween, carboxylated brassinolide and formic acid esterified spermidine are combined to form a fertilizer base full of emulsified liquid drops; and adding other nutrients to obtain the foliar fertilizer. The leaf fertilizer for increasing the amino acid content of rice can increase the content of amino acids, especially lysine, in grains on the premise of increasing the yield of rice, and nitrogen absorption and utilization of the rice grains are improved.

The invention relates to low-temperature lead-free formic acid solder paste and a preparation method and application thereof, and belongs to the technical field of welding materials. The low-temperature lead-free formic acid solder paste is prepared from the following raw materials in percentage by mass: 85-90% of alloy welding powder and 10-15% of scaling powder, the soldering flux comprises the following raw materials in parts by weight: 10-15 parts of an activating agent, 1-5 parts of a rheological agent, 20-30 parts of an organic solvent, 20-30 parts of a paste forming agent, 3-5 parts of a surfactant and 0.1-0.5 part of a corrosion inhibitor, the activating agent is a composition of hydrogenated dimer acid, glycollic acid and ethylenediaminetetraacetic acid, and the organic solvent is a composition of tetrahydrofurfuryl alcohol and cyclohexanol. The paste forming agent is polyethylene glycol. The solder paste is suitable for a low-temperature welding process at the temperature of 120-150 DEG C, welding energy consumption can be reduced, the residual rate after welding is low, follow-up cleaning is not needed, the production environment can be improved, and the production cost can be reduced.

The present invention relates to the technical field of the preparation of electrocatalysts, and in particular relates to a bismuth-copper bimetallic composite catalyst, and a preparation method therefor and the use thereof. The catalyst comprises ultra-small copper nanoclusters and bismuth nanosheets, wherein the bismuth nanosheets are of a polycrystalline structure, and the copper nanoclusters are highly dispersed on the bismuth nanosheets; and the number of copper atoms in each copper nanocluster is less than 10. In the present invention, highly-dispersed ultra-small copper nanoclusters are loaded on bismuth nanosheets by means of the thermal decomposition of a metal complex and a subsequent in-situ electroreduction method, the electronic state of bismuth atoms is adjusted, and therefore the carbon dioxide activating capacity of the bismuth-copper bimetallic compound is improved, thereby achieving high-selectivity and high-activity preparation of a formate by means of the electrocatalytic reduction of carbon dioxide, and providing a new path for the efficient conversion of carbon dioxide. The bismuth-copper bimetallic composite catalyst provided by the present invention achieves both a formate selectivity of more than 90% and an ultrahigh activity under conditions of 1.2 A cm-2.

The invention relates to an SNCR (selective non-catalytic reduction) denitration synergist, a denitration composition and a denitration method. The SNCR denitration synergist comprises an organic solvent and alkali metal carboxylate, the mass ratio of the organic solvent to the alkali metal carboxylate is (0.1-1): 1, and the organic solvent is selected from one or more of alcohol, ketone, ether and aldehyde. The alkali metal carboxylate is selected from at least one of formate, acetate, citrate, oxalate, ascorbate and tartrate of alkali metal. According to the SNCR denitration synergist, the denitration efficiency can be remarkably improved in a medium and low temperature interval (600-800 DEG C), ammonia escape is reduced, and secondary pollution is reduced.

A direct electrolysis technology for a natural mineral wet mineralization CO2 capture stock solution belongs to the field of carbon capture and resource utilization, and is characterized in that CO2 is captured through natural mineral wet mineralization to generate a bicarbonate solution, an electrolytic bath is constructed by using a bismuth-based catalyst and a cation exchange membrane to directly electrolyze to generate formate, and the formate is directly electrolyzed to generate the CO2 capture stock solution. Formate and regenerated trapping liquid are separated through a bipolar membrane electrodialysis technology, slag can be converted into a silicon-based building material, and integration of emission reduction, value addition and circulation is achieved. Compared with a traditional amine trapping technology, the method has the advantages that the energy consumption is reduced by 40%-50%, the trapping liquid raw material cost is reduced by 60%-70%, the problems of solvent volatilization and equipment corrosion are avoided, and the method is suitable for distributed carbon trapping and resource conversion in high-emission industries such as steel and chemical engineering.

The invention relates to the field of carbon dioxide capture and utilization, in particular to a method and system for producing formate through synergistic capture and conversion of flue gas carbon dioxide, formate is obtained through electrochemical conversion of carbon-rich capture liquid, capture liquid is generated, the capture liquid directly captures flue gas carbon dioxide, and the carbon-rich capture liquid is obtained again. And the carbon-rich trapping liquid is continuously recycled for electrochemical conversion. The carbon-rich capture liquid electrochemical conversion process and the flue gas carbon dioxide capture process do not need to be alternately carried out step by step, but are synchronously and continuously carried out in the same system, the whole process does not need to pre-treat a small amount of oxygen and trace nitrogen oxide and sulfur oxide gas impurities in the flue gas, and a high-energy-consumption carbon dioxide gas regeneration step is avoided; the method overcomes the defect of low single conversion rate of electrochemical conversion of carbon dioxide gas, realizes collaborative capture and conversion of flue gas carbon dioxide to produce formate, and finally realizes direct conversion and utilization of carbon dioxide from flue gas to a high-value product formate.

The invention provides a photocuring composition and application thereof. The composition comprises the following components: (a) at least one benzoyl formate compound; (b) at least one ethylenically unsaturated photopolymerizable compound; the benzoyl formate compound is obtained by reacting a compound shown in a general formula (I) with a compound shown in a general formula (II) or a general formula (III), or is obtained by further reacting the compounds shown in the general formula (I), the general formula (II) and the general formula (III) with a compound with an end-capped substituent group for end capping. The sensitivity of the obtained product is not reduced compared with that of existing small molecules, and the hardness of the product is improved under LED curing.

The invention provides a Co (at) CeO2-x heterogeneous catalytic electrode as well as a preparation method and application thereof. The Co-coated CeO2-x heterogeneous catalytic electrode comprises foamed nickel and an electrocatalyst loaded on the surface of the foamed nickel, and the electrocatalyst comprises metal Co particles and CeO2-x with oxygen vacancy. The Co (at) CeO2-x heterogeneous catalytic electrode provided by the invention is prepared only through a process combining a room-temperature electrodeposition method and an air calcination method, has a three-dimensional self-supporting integrated structure, and also has a heterostructure and a porous nanosheet structure, so that more reaction active sites can be exposed, the interface charge transfer capability can be improved, and the catalytic performance can be improved. And the composite material has excellent activity and stability when being used as a cathode and an anode in the application of preparing formate and hydrogen by electrolyzing water under the assistance of glycerol.

The invention discloses a preparation method and application of a mesoporous anti-perovskite structure electrocatalyst for producing formate through electrooxidation of glucose, and belongs to the technical field of catalysts. The preparation method of the catalyst comprises the following steps: (1) dispersing Kit-6, copper nitrate and nickel nitrate in a mixed solution to obtain a solution 1; (2) incubating the solution 1 in a drying oven, and evaporating to dryness to obtain a powder precursor 1; (3) transferring the powder precursor 1 into a muffle furnace, and calcining to obtain a powder precursor 2; (4) adding the powder precursor 2 into sodium hydroxide, etching in a drying oven, washing and drying to obtain a powder precursor 3; and (5) transferring the powder precursor 3 into a tubular furnace, and calcining in an NH3 atmosphere to obtain the mesoporous anti-perovskite structure electrocatalyst. The catalyst prepared by the invention uses non-noble metal, so that the synthesis cost is reduced; the preparation process is simple. The catalyst is applied to production of formate through electrooxidation of glucose, and has the advantages of high catalytic stability, high formate yield and the like.

The invention provides a device for extracting cesium from lepidolite and preparing cesium formate by a preparation system of cesium formate, which comprises: an extraction section, which comprises a plurality of first high-speed centrifugal extractors connected in series, and a first extraction inlet of the first high-speed centrifugal extractor of the last stage is introduced with a liquid to be extracted; the to-be-extracted liquid is leached frozen clear liquid of lepidolite, and the frozen clear liquid is alkaline and comprises cesium, rubidium, sodium, potassium and lithium ions; the t-BAMBP is diluted by adopting ESCAID 110 as an extraction agent, the concentration of the extraction agent is 0.4-0.6 mol / L of t-BAMBP, and the O / A ratio in the extraction section is 1: (1.8-2.0); the washing section comprises a plurality of second high-speed centrifugal extractors which are connected in series; the back extraction section comprises a third high-speed centrifugal extractor, and cesium bicarbonate back extraction post-liquid flows out of a first back extraction outlet of the third high-speed centrifugal extractor; the oil removal section is used for removing oil from the cesium bicarbonate back-extraction post-liquid; and the evaporation and concentration section is used for introducing formic acid for neutralization reaction to form a cesium formate solution after oil removal, and then evaporating and concentrating the cesium formate solution to obtain the final cesium formate solution.

Compositions and methods for a hybrid biological and chemical process that captures and converts carbon dioxide and / or other forms of inorganic carbon and / or CI carbon sources including but not limited to carbon monoxide, methane, methanol, formate, or formic acid, and / or mixtures containing CI chemicals including but not limited to various syngas compositions, into organic chemicals including biofuels or other valuable biomass, chemical, industrial, or pharmaceutical products are provided. The present invention, in certain embodiments, fixes inorganic carbon or CI carbon sources into longer carbon chain organic chemicals by utilizing microorganisms capable of performing the oxyhydrogen reaction and the autotrophic fixation of CO2 in one or more steps of the process.

The invention relates to a chemically modified high-strength high-temperature-resistant polyurethane fiber and a preparation method thereof.The preparation method comprises the following steps that 1, oligomer mixed polyol and diisocyanate are subjected to a full prepolymerization reaction, a solvent is added for full dissolution, and a-NCO-terminated prepolymer polyurethane formate solution is obtained; 2) adding hydroxyalkyl silane and a catalyst into the prepared prepolymer, and fully reacting to obtain a modified prepolymer; (3) carrying out chain extension reaction and chain termination reaction on the prepared modified prepolymer to obtain a polyurethane urea solution; (4) adding an antioxidant, an ultraviolet light absorber, an anti-yellowing agent, a delustering agent and a lubricating and releasing agent into the polyurethane urea solution to prepare a polyurethane spinning solution; and (5) preparing the high-strength high-temperature-resistant polyurethane from the prepared polyurethane spinning solution by virtue of a dry spinning system. According to the invention, a polyurethane molecular chain is subjected to functional chemical modification, so that the product has the characteristics of high temperature resistance and high strength.

The invention belongs to the technical field of electrocatalytic carbon dioxide reduction, and particularly relates to a green and high-activity method for preparing formate through electrocatalytic carbon dioxide reduction. Comprising the following steps: loading a cathode catalyst on cathode carbon paper to obtain a catalytic cathode; loading an anode catalyst on the anode titanium felt to obtain a catalytic anode; constructing a flowing electrolytic tank by utilizing the catalytic cathode and the catalytic anode; carbon dioxide gas is introduced into the gas flow channel, so that the carbon dioxide gas is diffused to the catalytic cathode; an alkaline electrolyte is introduced into the liquid flow channel, so that the alkaline electrolyte flows through the catalytic anode; and voltage is applied to the flowing electrolytic tank for an electrolytic reaction, a product of the catalytic anode is collected, and formate is obtained after concentration and distillation. The method disclosed by the invention can be operated for a long time under the current density of 500-600mA / cm < 2 >, and the formate content in the formate solution can reach about 13%.

The invention discloses a citric acid coordination regulated amino-functionalized palladium-silver alloy catalyst as well as a preparation method and application thereof. Nitrogen-doped carbon is used as a carrier, and the palladium-silver alloy catalyst is constructed through coordination-confinement in-situ reduction of citric acid. According to the preparation method, citric acid is introduced, and synergistic interaction of sub-nano-scale dispersion and efficient interface mass transfer is achieved through dual synergistic regulation and control of the size and the interface; the coordination effect enables the palladium-silver alloy to achieve sub-nano-scale superfine dispersion; as a competitive hydrogen bond acceptor / donor, the polycarboxyl group can effectively break an interface hydrogen bond network and inhibit the formation of a tight gas film from the source. The mechanism ensures that the catalyst is always in full contact with a mixed aqueous solution containing formic acid and formate and hydrogen is quickly released during formic acid dehydrogenation hydrogen production reaction, so that the catalyst has excellent anti-poisoning cycling stability while keeping high intrinsic activity, and the technical problem that high activity and long-term stability are difficult to consider at the same time is solved.

The invention provides a grain boundary defect-enriched cerium dioxide nano catalyst and a preparation method thereof, and the preparation method comprises the following steps: preparing a cerium salt solution with nitrate radicals, reacting to obtain cerium formate and basic cerium carbonate precursor products, and washing, drying and roasting to obtain the grain boundary defect-enriched cerium dioxide nano catalyst. The cerium dioxide nano-catalyst prepared by the method can form an oxygen vacancy defect, promote the adsorption and activation of O2, form peroxy, superoxide and other active oxygen species, and improve the catalytic oxidation activity. According to the method, the covalence of Ce-O bonds is effectively reduced by destroying the periodicity of CeO2 crystal lattices. The reduction of covalence can weaken the constraint strength that surface lattice oxygen atoms are surrounded by Ce atoms and enhance the release reactivity of the surface lattice oxygen atoms essentially, so that the formation of oxygen deficiency is further promoted, the CeO2 adsorption is enhanced, the activity of activating O2 to form active oxygen for oxidation reaction is enhanced, and the oxidation reaction efficiency is improved. Furthermore, the catalyst has good catalytic performance on toxic and harmful substances such as chlorobenzene, sarin toxic agent simulation agents, CO and the like.

This application relates to the field of functional crystalline material preparation and microfluidic application technology, specifically disclosing a method and product for preparing formate crystals using core-shell microcapsules, including the following steps: (1) dissolving a solid alkaline raw material in a formic acid solution to prepare reaction solution a; (2) separately conveying polymer solution A and polymer solution B with phase separation characteristics, and reaction solution a, so that they are mixed at the intersection of microchannels to prepare dispersed phase b, which is then introduced into the assembly zone for phase separation assembly to form core-shell microcapsules; (3) the core-shell microcapsules are crystallized in a continuous temperature-changing crystallization zone to form formate solid; (4) the formate solid is collected, washed and dried sequentially to obtain the target product; (5) the oil layer is continuously extracted and returned to the assembly zone for recycling. The formate crystals prepared in this application not only have a large particle size, but also exhibit good size uniformity and morphological repeatability, and have the advantages of high throughput, green environmental protection, and simple operation.

The present application relates to a kind of preparation method of vicinal diol compound, which comprises the following steps: in non-aqueous solvent, formula (I) compound and reducing agent are reacted under light condition, to obtain the vicinal diol compound shown in formula (II);The reducing agent is formic acid or formate;The wavelength of the light is less than 390nm;Its reaction formula is as follows.The preparation method of the present application does not need transition metal catalyst, also does not need other special catalyst and special additive, and the aldehyde ketone substrate can be reacted with formic acid or formate in solvent by specific wavelength of light, to obtain corresponding vicinal diol compound with high yield, its reaction condition is mild, has wide substrate applicability, and green and environmental protection, simple and practical operation method, provides an effective synthesis strategy for the synthesis of shikimic alcohol compound.

The present invention discloses a triazine benzoate compound having the structure shown in formula (I) or a stereoisomer:The definition of each substituent in the formula I is described in the description. The compound of the formula I of the present invention has excellent herbicidal activity and can be used for controlling weeds.

The invention belongs to the technical field of chemical synthesis, and particularly relates to a synthesis method of 1-(tert-butyl)-3-ethyl-4-(4, 4, 5, 5-tetramethyl-1, 3, 2-dioxaborane-2-yl)-5, 6-dihydropyridine-1, 3 (2H)-dicarboxylate. According to the invention, 1-(tert-butyl)-3-ethyl-4-oxopiperidine-1, 3-diformate, namely the compound A, is taken as a base material, two-step reaction is carried out, the reaction conditions are relatively mild, the product yield is high, and the operation is easy.

The invention provides a three-dimensional multi-stage needle tip array type Bi-CuO integral electrode as well as a preparation method and application of the three-dimensional multi-stage needle tip array type Bi-CuO integral electrode. The integral electrode comprises foamy copper, a copper oxide needle tip array layer growing on the foamy copper and a bismuth nanosheet array layer uniformly covering the surface of a copper oxide needle tip. The integral electrode has a multi-stage self-supporting structure, so that catalyst aggregation or stacking is effectively avoided, and the specific surface area of exposed active sites is remarkably increased; and the electrode also has multiple heterogeneous interfaces, and shows excellent catalytic activity, selectivity and electrochemical window when being used as a working electrode for electrically reducing CO2 to prepare formate. The preparation method comprises the following steps: generating the copper hydroxide nanowire layer on foamy copper in situ by using a chemical oxidation method, performing annealing treatment in air to form the copper oxide needle tip array layer, and depositing the bismuth nanosheet array layer on the surface of the copper oxide needle tip by using a wet chemical method to obtain the integral electrode. The preparation method is novel and simple, the use of a binder is avoided, the operability is high, and the preparation method has a good application prospect.

The invention relates to a synthesis method of novel energy-saving phosphorus-doped copper oxide, a catalyst as well as a preparation method and application of the catalyst. The synthesis method comprises the following steps: S100, obtaining copper oxide nanoparticles; s200, obtaining a black phosphorus nanosheet; s300, the copper oxide nanoparticles and the black phosphorus nanosheets are mixed and then subjected to ultrasonic treatment, and phosphorus-doped copper oxide is obtained.According to the method, the phosphorus-doped copper oxide nanoparticle catalyst can be synthesized under the mild condition, and very high methanol oxidation reaction activity and formate selectivity are achieved.

The invention discloses a synthetic carbamate compound based on 3-substituted dioxazolone as well as a preparation method and application of the synthetic carbamate compound, and belongs to the technical field of organic synthesis. The synthesis method comprises the following steps: (1) preparing 3-substituted dioxazolone from hydroximic acid with different substituent groups and phosgene under an ice bath condition; and (2) reacting the 3-substituted dioxazolone obtained in the step (1) with different phenols (alcohols) under an alkaline condition to obtain corresponding carbamate compounds. According to the method, the yield of carbamate is further improved by adjusting the conditions of alkali, equivalent weight, temperature and the like; the preparation method provided by the invention is novel and has the advantages of mild reaction conditions, few generated impurities, high yield, high safety, convenience in operation and the like; and the compound shows good cholinesterase activity in activity screening, and can be used in insecticides or pesticides.

A simple synthetic method of adamantane formate belongs to the technical field of adamantane formate, and comprises the following steps: 1) preparing adamantane formyl chloride: under the protection of nitrogen, carrying out heating reflux reaction on adamantane carboxylic acid and an acyl chloride reagent at 0-70 DEG C for 3-6 hours, and then carrying out rotary evaporation to obtain adamantane formyl chloride; dichloromethane, an acid-binding agent and an alkyl alcohol / alkylphenol mixture are added into the adamantane formyl chloride obtained in the step 1 through a dropping funnel, the mixture reacts for 8-10 h at the temperature of 0-30 DEG C, adamantane formate is synthesized and can be used for preparing lubricating oil, and the method is easy and convenient to implement, high in reaction rate, high in product yield and high in purity.

The invention relates to a method for separating an n-propyl formate-n-propyl alcohol-water mixture by liquid-liquid phase separation coupling extractive distillation, which comprises the following steps of: dividing a raw material into a water phase and an organic phase by using a phase splitter based on the heterogeneous characteristic of an azeotropic system, and carrying out four-tower operation on a rectifying tower (C1), a rectifying tower (C2), a rectifying tower (C3) and a rectifying tower (C4) to obtain an n-propyl formate-n-propyl alcohol-water mixture. The efficient separation of the n-propyl formate-n-propyl alcohol-water mixture is realized. After separation, the molar fraction of n-propyl formate is greater than 99.99%, the molar fraction of n-propyl alcohol is greater than 99.99%, and the molar fraction of water is greater than 99.99%. The method provided by the invention realizes high-efficiency and low-energy-consumption separation of the n-propyl formate-n-propanol-water azeotropic mixture, and has economic benefits and environmental friendliness.

The invention discloses a polyurethane or polyurea aqueous dispersion with high humidity and heat resistance as well as a preparation method and application thereof. The aqueous dispersion is prepared by reacting the following components: a) polyester diol and / or polyol, b) di-and / or polyisocyanate which at least contains more than 50% by mass of toluene diisocynate, c) a monofunctional or polyfunctional polyethoxy chain segment-containing component which is synthesized by taking sodium methoxide as a catalyst and has reaction activity to isocyanate, and d) a polyethoxy chain segment-containing component which has reaction activity to isocyanate. D) a sulfonic acid type hydrophilic compound; e) a low molecular compound containing hydroxyl and containing at least two NCO reactive amino groups; wherein the ratio of the sodium ions in the component c) to the toluene diisocynate in the component b) is 10 ppm to 100 ppm. Sodium ions can catalyze a small amount of isocyanate groups to react with carbamate bonds to generate allophanate bonds in a polyurethane synthesis process, so that a trace cross-linked structure is introduced into a polyurethane chain segment, and the heat resistance / damp heat resistance of a product is improved.

The utility model relates to the related technical field of heat exchangers for formate preparation, and one embodiment of the utility model provides a heat exchanger for formate preparation, which comprises a bottom plate and a shell, the shell is fixed at the top of the bottom plate, connecting pipelines are respectively connected to the top and the bottom of the shell, and an outer cover is arranged outside the shell. The telescopic switch assembly is arranged between the outer cover and the shell, the heat exchange connecting assembly is arranged on the outer cover and comprises an installation groove, the installation groove is formed in the side surface of the outer cover, a sealing plate is installed in the installation groove, and a plurality of heat exchange pipelines are arranged on the surface of the sealing plate. By means of the technical scheme, the technical problem that in the prior art, due to the fact that the heat exchange pipes are fixed and difficult to detach, once corrosion damage occurs, the heat exchange pipes cannot be independently replaced, and the whole heat exchanger needs to be maintained or replaced generally is solved.

The invention discloses a palladium-based electrocatalyst as well as a preparation method and application thereof, and belongs to the technical field of catalysis. The palladium-based electrocatalyst provided by the invention comprises a composite carrier and palladium particles, the palladium particles are loaded on the composite carrier; the composite carrier comprises a fusiform titanium dioxide carrier and reduced graphene oxide quantum dots; the reduced graphene oxide quantum dots are modified on the surface of the fusiform titanium dioxide carrier. Reduced graphene oxide quantum dots are introduced as a functional modifier of titanium dioxide to synergistically enhance metal-carrier interaction and induce generation of oxygen vacancies, so that the electrocatalytic oxidation performance on formate, ethanol and methanol is remarkably improved.

The present application provides a kind of isocyanate prepolymer composition and its preparation method which can be stably stored.The composition contains isocyanate prepolymer, phosphine compound.The phosphine compound does not react with isocyanate in the system, and can capture basic or metal catalyst in the prepolymer compound system to deactivate it, reduce the further reaction of isocyanate and carbamate / uretonimine crosslinking, and further reduce the generation of macromolecular polymer, reduce the viscosity and composition change of product, and thus improve the storage stability of product.