510 results about "Dehydration reaction" patented technology

The invention discloses an efficient chemical liquid phase coating method of metal soft magnetic powder and application, and belongs to the technical field of preparation of soft magnetic materials, aluminum isopropoxide is dissolved to form a coating precursor solution, and an Al2O3 insulation coating layer is formed on the surface of the fluidized metal soft magnetic powder after hydrolysis and dehydration reactions. The aluminum isopropoxide is dissolved to form gel, the gel is uniformly mixed with the fluidized metal soft magnetic powder, dried gel can be formed on the surface of the metal soft magnetic powder after high-temperature airflow drying, and the dried gel is further calcined and dehydrated to form the high-insulativity Al2O3 coated metal soft magnetic powder. The method can be widely applied to surface insulation coating of the metal soft magnetic powder, has the characteristics of controllable coating layer thickness, simplicity, rapidness and high coating efficiency, and meets the requirements of industrial production such as large-scale, low-cost, safe and environment-friendly industrial production.

The invention discloses a nano material modified alcohol amine grinding aid as well as a preparation method and application thereof, and the preparation method comprises the following steps: firstly, carrying out esterification reaction on alcohol amine and an acid small monomer containing double bonds to generate an esterification product; then, carrying out bulk polymerization on the esterification product and a silane coupling agent KH-570; and finally, combining the bulk polymerization product with the nano-material through a dehydration reaction of a silane coupling agent and hydroxyl on the surface of the nano-material to form the nano-material modified alcohol amine grinding aid. According to the invention, the nano material is directly grafted into the alcohol amine, so that the dispersity of the nano material in the cement grinding process can be effectively optimized, the friction force and energy consumption among cement particles can be reduced, the efficiency and stability of the cement production process can be improved, and the strength and durability of the cement product are improved.

The invention discloses a Schiff base modified silane / polyurethane antifouling coating as well as a preparation method and application thereof. The preparation method comprises the following steps: S1, carrying out dehydration reaction on an aldehyde substance and amino silane, and hydrolyzing to prepare a Schiff base modified silane monomer; s2, dewatering polyether glycol, uniformly mixing the dewatered polyether glycol with diisocyanate, and carrying out cooling reflux under the conditions of stirring and 60-80 DEG C to obtain a polymer A; s3, uniformly mixing the polymer A, a Schiff base modified silane monomer, a solvent and a dibutyltin dilaurate catalyst, and reacting to obtain a polymer B; and S4, coating a base material with the polymer B, and curing to obtain the coating. The anti-fouling coating has a good anti-fouling effect, the coating can effectively inhibit growth of marine fouling organisms based on Schiff base, the active anti-fouling requirement of the coating can be met, meanwhile, the coating has good base material adhesion and wear resistance, and the service life of the coating is guaranteed.

A system for preparing acrylic acid by utilizing carbon dioxide through electro-biological coupling is characterized by comprising an electro-catalysis methanol production unit, a biological fermentation 3-hydracrylic acid production unit, a 3-hydracrylic acid purification unit and an acrylic acid production unit which are connected in sequence, the electro-catalysis methanol production unit is used for carrying out electro-catalysis on hydrogen produced by water through solar electrolysis and carbon dioxide directly captured by air under the action of a ZnO-ZrO2 catalyst to obtain methanol; the unit for producing the 3-hydracrylic acid through biological fermentation takes the methanol obtained by the electrocatalysis unit as a substrate to carry out biological fermentation, and a fermentation product is subjected to gas-liquid separation to obtain fermentation liquor containing the 3-hydracrylic acid; the 3-hydracrylic acid purification unit is used for carrying out solid-liquid separation on the obtained fermentation liquor of the 3-hydracrylic acid and extracting to obtain the 3-hydracrylic acid; the acrylic acid production unit is used for carrying out dehydration reaction on the purified 3-hydracrylic acid to obtain acrylic acid; carbon dioxide is fixed through an electrocatalysis and biological fermentation coupling technology, and the problem that existing fossil-based raw materials are high in dependency degree is solved.

The present invention discloses a method, device and application for producing aviation kerosene from methanol, and belongs to the field of petrochemical product processing technology. The method comprises: generating a methanol dehydration reaction product from a methanol raw material under the catalytic action of a first molecular sieve catalyst, separating and treating the methanol dehydration reaction product, and then mixing it with one or more of recycled fuel gas, recycled liquefied gas or recycled gasoline under the catalytic action of a second molecular sieve catalyst to generate a reaction oil gas, the reaction oil gas is fractionated to obtain a kerosene fraction, and the kerosene fraction is subjected to a hydrogenation and refining treatment to obtain aviation kerosene. The method for producing aviation kerosene using methanol as a raw material provided by the present invention has opened up a new way to produce aviation kerosene; the process flow is short and compact, and can effectively achieve energy conservation and emission reduction.

The invention belongs to the field of fine chemical engineering, and particularly relates to a continuous production device and method of high-purity isosorbide. The device comprises a reaction unit, a separation unit and a purification unit which are sequentially connected, the reaction unit comprises a preheater and a reactor, the separation unit comprises a settling tank, a filter, a dehydrating tower and a distillation tower, and the purification unit comprises a decolorizing tower, a rectifying tower and a crystallizing tower. A sorbitol raw material enters a preheater to be preheated, the preheated material enters a reactor to be subjected to a dehydration reaction, the reacted material flows out of a discharging port in the upper portion of the reactor to enter a shell pass of a dehydration tower to be subjected to heat exchange and cooling, the cooled material enters a settling tank to settle solid waste, supernate enters a filter to be filtered, and a liquid phase flows into the dehydration tower to be subjected to water removal and concentration; and distilling out crude isosorbide in a distillation tower, and purifying the isosorbide crude product through a decolorizing tower, a rectifying tower and a crystallizing tower to obtain the high-purity isosorbide. The method has the outstanding characteristics of continuous production, separation and purification, and continuous production of high-purity isosorbide can be realized.

The present invention provides a method for producing an aromatic nitrile compound, the method comprising a dehydration reaction wherein a desired compound can be selectively obtained with high yield while suppressing the generation of by-products during the regeneration of an aromatic amide compound into the corresponding aromatic nitrile compound. In addition, the present invention realizes a method for efficiently producing a carbonate ester by applying the abovementioned production method to a method for producing a carbonate ester. The above are achieved by means of a method for producing an aromatic nitrile compound involving a dehydration reaction wherein an aromatic amide compound is dehydrated, the method having a contact step for bringing the aromatic amide compound into contact with a catalyst in a gas phase during the dehydration reaction.

The invention discloses a steam supply system based on calcium hydroxide thermochemical energy storage and an operation method. The system comprises a thermochemical energy storage device, a steam supply device, an electric heating device and a material circulation auxiliary device. The thermochemical energy storage device is a fluidized bed reactor and a solid material storage tank, reversible conversion between high-grade heat energy and chemical energy is achieved through hydration / dehydration reaction, then heat energy storage is achieved, and the thermochemical energy storage device is matched with the auxiliary device to form a closed material circulation loop. The steam supply device integrates multiple paths of steam through a valve and a mixer; the electric heating device serves as a supplementary heat source in the peak regulation stage of the coal-fired heat supply unit. The operation method is divided into a starting stage, a non-peak-shaving stage and a peak-shaving stage, and cooperative control over high-pressure steam extraction heat energy storage and low-temperature water supply evaporation overheating is achieved. The system aims to solve the thermoelectric decoupling problem of the coal-fired heat supply unit, and has the advantages of flexibility, high efficiency, safety, environmental protection, low application cost, high energy storage density, small occupied area and the like.

A method for continuously preparing 2,2,5,5-tetramethyltetrahydrofuran and a catalyst used therefor. In the method for continuously preparing 2,2,5,5-tetramethyltetrahydrofuran, 2,5-dimethyl-2,5-hexanediol is subjected to a dehydration reaction in the presence of the catalyst in a reactor at a temperature of 50-200°C. The catalyst for synthesizing 2,2,5,5-tetramethyltetrahydrofuran can catalyze the reaction of 2,5-dimethyl-2,5-hexanediol at a higher conversion rate, and the reaction has very high selectivity of up to 99% or more. The catalyst used therefor has good stability and a long service life, so that the production energy consumption is further reduced, the production cost is reduced, and industrial production is easy to realize.

The invention belongs to the technical field of perfume preparation processes, and particularly relates to a preparation process of fragrance lasting type perfume ligustral, which comprises the following steps: a catalytic dehydration step: mixing isohexylene glycol and a composite catalyst according to a mass ratio of 100: (0.8-1.2), and carrying out a catalytic dehydration reaction under a gradient heating condition to generate a methyl pentadiene mixture; a Diels-Alder addition step: carrying out an addition reaction on acrolein and a methyl pentadiene mixture according to a mass ratio of 1: (1.05-1.15) under a sectional temperature control condition, controlling the reaction pressure to be 0.25-0.35 MPa, carrying out a heat preservation reaction for 2 hours, and cooling to obtain a ligustral crude product; and a three-tower series rectification step: separating and purifying the ligustral crude product after the addition reaction through a light component removal tower, a middle component removal tower and a refining tower in sequence to obtain a ligustral finished product. By optimizing a catalytic system, reaction conditions and a separation process, the purity and aroma durability of the product are improved.

The invention relates to a water-repellent polyester fiber and a preparation method thereof. The preparation method comprises the following steps: firstly, carrying out dehydration reaction on hydroxyl-terminated hyperbranched polyester and asymmetric alcoholic hydroxyl single-terminated polydimethylsiloxane to obtain siloxane-terminated hyperbranched polyester; then, polyethylene glycol terephthalate I, siloxane-terminated hyperbranched polyester and dimethyl vinyl siloxy polyhedral oligomeric silsesquioxane are subjected to melt blending to prepare a water-repellent polyester functional master batch, polyethylene glycol terephthalate II and the water-repellent polyester functional master batch are blended, and melt spinning is performed; and finally, coating the surface of the fiber obtained by melt spinning with tri-tert-butoxyvinyl silane, and inducing a grafting reaction through ultraviolet radiation to prepare the water-repellent polyester fiber. The number-average molecular weight of the polyethylene glycol terephthalate I and the polyethylene glycol terephthalate II is in the range of 20000-30000 g / mol; and the contact angle of the water-repellent polyester fiber is greater than 145 degrees. The method is simple; and the prepared product has good mechanical properties and water repellency.

The invention discloses modified hydroxytyrosol, a cosmetic, a preparation method and application. The provided preparation method of the modified hydroxytyrosol comprises the following steps: in the presence of an acidic solvent, mixing hydroxytyrosol, lipase and fatty acid ester for reaction, centrifugally layering a reaction product, and collecting components of a middle layer to prepare the modified hydroxytyrosol. According to the provided preparation method of the modified hydroxytyrosol, lipase and fatty acid ester are subjected to an enzyme digestion reaction, an active hydroxyl group in a product obtained through the enzyme digestion reaction and hydroxytyrosol are subjected to a dehydration reaction, so that an ester group molecular chain is grafted into hydroxytyrosol, and a modified hydroxytyrosol product with an ester group is prepared. And the obtained modified hydroxytyrosol has relatively high fat solubility and oxidation resistance.

The invention relates to the field of photovoltaic adhesive films, and particularly discloses an adhesive film, and a composition and a method for reducing relative displacement of the adhesive film and glass in a humid environment. A composition for reducing relative displacement of an adhesive film and glass in a humid environment comprises silane contained in the adhesive film and a silane hydrolysis catalyst, and the silane hydrolysis catalyst promotes hydrolysis of the silane, so that the adhesive film is bonded with the glass; the adhesive film comprises polyolefin matrix resin, a cross-linking agent, an assistant cross-linking agent, a silane hydrolysis catalyst and silane. The adhesive film disclosed by the invention has the advantages that in a humid environment, water vapor is attached to the surface of the glass, and under the action of the silane hydrolysis catalyst, silane accelerates hydrolysis, and is subjected to a dehydration reaction with hydroxyl of the glass to form chemical bonds, so that the adhesive force is enhanced, an anti-slip effect is achieved, and the adhesive film is unlikely to relatively slip.

The present invention discloses a method for preparing furfural, which includes: under the action of a heteropolyacid-based phase transfer catalyst, an intramolecular dehydration reaction occurs for xylose-based carbohydrates in a ternary two-phase reaction medium composed of a low-boiling organic solvent, a protic solvent, and an ionic organic ammonium chloride. The catalyst used in the present invention has the property of phase transfer, that is, its solubility in the reaction medium increases at high temperature, and it catalyzes the dehydration of xylose in the form of a liquid acid; after the reaction, the solubility decreases and it precipitates in the form of a solid, which is convenient for the recovery and separation of the catalyst, and largely solves the problems of low efficiency of solid acid catalysts and difficult separation of liquid acid catalysts. And an advanced reaction medium is coupled to increase the solubility of xylose-based carbohydrates and the solvation effect on xylose. Through the optimization of the catalyst and the reaction medium, the reaction performance of the reaction system is effectively improved.

The invention belongs to the technical field of high polymer materials, and particularly relates to a Si-P-N ternary hybrid flame retardant and a preparation method thereof.The method comprises the steps that wollastonite, a silane coupling agent KH570, ethyl alcohol and water are mixed and react to obtain a dehydration reaction product, then organic silicon resin and acetic acid are added into the dehydration reaction product, and a condensation polymerization reaction product is obtained after a reaction; the preparation method comprises the following steps: adding melamine and triphenyl phosphate into a solvent, reacting to obtain a polymer, mixing a polycondensation reaction product with the polymer, reacting to obtain an addition reaction product, adding a silane coupling agent KH570 into the addition reaction product, reacting to obtain a final reaction product, and drying the final reaction product to remove the solvent, thereby obtaining the Si-P-N ternary hybrid flame retardant. Nitrogen in the melamine, phosphorus in the triphenyl phosphate and silicon in the wollastonite fiber play a synergistic flame-retardant role, so that the flame-retardant property of the material is improved; the silane coupling agent KH570 is added twice, so that the interfacial compatibility is improved, and the mechanical properties of the material are not influenced.

The invention discloses a modified POSS (Polyhedral Oligomeric Silsesquioxane) and derivative flame-retardant synergist thereof, a preparation method of the flame-retardant synergist, a thermoplastic polyester elastomer material and a preparation method of the thermoplastic polyester elastomer material. The modified POSS and derivative flame-retardant synergist compound 1 and compound 2 are prepared through a dehydration reaction under the action of a catalyst, and the thermoplastic polyester elastomer material comprises the following ingredients in parts by weight: 80-120 parts of thermoplastic polyester elastomer, 2-12 parts of modified POSS and derivative flame-retardant synergist, 2-10 parts of a flame retardant, 0.5-1 part of a lubricant and 0.5-1 part of an antioxidant. The high-flame-retardancy thermoplastic polyester elastomer material provided by the invention has excellent flame retardancy and physical and mechanical properties, and the anti-dripping effect is greatly improved.

A method of producing pentaerythritol mercaptocarboxylate including subjecting a mercaptocarboxylic acid and pentaerythritol to a dehydration reaction under solvent-free conditions, a polymerizable composition containing the pentaerythritol mercaptocarboxylate, a resin which is a cured product of the polymerizable composition, an optical material containing the resin, and a spectacle lens containing the resin.

The present invention discloses a preparation method and application of a rust-resistant polycarboxylate water reducer, including an imidazoline derivative preparation step: mixing alkyl N-hydroxyethyl imidazoline with allyl chloride and adding it to a reactor, and adding sodium hydroxide, sequentially performing substitution and dehydration reactions to obtain an imidazoline derivative; a p-isopropenylphenol polyalkoxy ether preparation step: taking p-isopropenylphenol into an autoclave, under high pressure conditions, raising the reaction temperature, adding ethylene oxide and propylene oxide to obtain p-isopropenylphenol polyalkoxy ether; a rust-resistant polycarboxylate water reducer preparation step: mixing p-isopropenylphenol polyalkoxy ether, an imidazoline derivative and deionized water and adding them to a reaction device, heating and stirring to generate a polyether monomer, then adding acrylic acid and an oxidant, and finally sequentially adding a reducing agent, an initiator, and a chain transfer agent, and neutralizing to obtain a rust-resistant polycarboxylate water reducer. The rust-resistant polycarboxylate water reducer prepared by the present invention has good rust-resistant performance and water-reducing performance.

The invention discloses a green production process for synthesizing 1, 8-terpineol and preparing perfume-grade terpilenol by dehydrating the 1, 8-terpineol, which comprises the steps of hydration reaction, centrifugal separation, acid water recovery, by-product recovery, dehydration reaction and secondary distillation. Wherein the turpentine hydration reaction conditions are as follows: a catalyst is composed of alpha-hydroxy acid and phosphoric acid or boric acid, intermittent stirring is performed at room temperature, the reaction is performed for 2-15 days, an IBC ton barrel can be adopted as a reaction tank, and the mass yield of terpin hydrate is greater than 100%. Citric acid or tartaric acid is adopted to catalyze the dehydration reaction of terpineol hydrate, and the selectivity of terpineol can reach 91% or above. Compared with a traditional process, the method has the advantages that the catalyst is low in corrosivity and does not need an enamel reaction kettle; the reaction is carried out at room temperature, and no cooling equipment is needed; centrifuging to obtain terpin hydrate crystals without alkali neutralization; acid water is easy to recycle, and almost no wastewater is discharged; an IBC barrel is used as a reactor, so that the equipment investment is low.

The invention provides a process and system for synthesizing a bismaleimide compound, and relates to the technical field of chemical synthesis, and the process comprises the following steps: (1) amidation reaction; (2) ring-closure dehydration reaction; (3) recovering the organic solvent; (4) a toluene thermal washing process; (5) a cooling crystallization process; (6) alkali washing process; (7) washing with hot water; and (8) drying. The process provided by the invention is high in production efficiency, the synthesized bismaleimide product is high in yield and purity, and compared with the prior art, the process is a clean production process in which the solvent can be recycled, no waste liquid is generated, the environment-friendly requirement is met, and the process has great environmental benefits, social benefits and economic benefits.

The invention relates to a method for preparing norambrox ether from sclareolide. The method comprises the following steps: 1) preparing a red aluminum toluene solution; 2) dissolving sclareolide with toluene to obtain a sclareolide toluene solution, adding the sclareolide toluene solution into the red aluminum toluene solution for complete reaction, and quenching with a NaCl solution to obtain a reactant containing sclarediol; 3) carrying out oil-water separation on the reactant to obtain a primary organic phase and a water phase, so as to obtain an organic phase containing sclarediol; 4) carrying out a dehydration reaction on the organic phase containing sclarediol by using a molecular sieve, and after the reaction is completed, separating out an organic phase containing norambrox ether; 5, the organic phase containing the norambergyl ether is subjected to distillation concentration and crystallization separation, and a norambergyl ether product is obtained.According to the method, sclareolide is reduced through the red aluminum, and compared with lithium aluminum hydride, hydroboron and red aluminum, the red aluminum has the advantages of being good in stability, beneficial to industrialization, low in reaction temperature and safe.

This invention relates to the field of chemical synthesis technology and discloses a method for preparing 2,5-furandicarboxylic acid from fructose, comprising the following steps: preparing reaction system A containing fructose, an organic bromide, a solid acid catalyst, and water; performing a dehydration reaction to separate the solid acid catalyst and obtain a fructose dehydration reaction solution; preparing reaction system B containing the fructose dehydration reaction solution, a co-oxidant, an oxidation catalyst, and acetic acid; performing an oxidation reaction under an oxidizing gas atmosphere; separating the product to obtain 2,5-furandicarboxylic acid. This invention utilizes a co-oxidant, which can reduce the requirement for fructose concentration in the one-pot preparation of 2,5-furandicarboxylic acid while ensuring the yield and purity of FDCA, thereby improving production efficiency. Furthermore, it reduces or even eliminates the use of hydrobromic acid in the oxidation reaction, thus reducing corrosion to equipment.

The present invention relates to the technical field of alcohol dehydration, and specifically to a catalyst for producing alpha-olefins by dehydrating alcohol, a preparation method thereof, and a method for producing alpha-olefins by dehydrating alcohol. The catalyst comprises: 84-99.88 wt% of a main component, 0.04-6 wt% of a Group IIA oxide, 0.05-8 wt% of a Group IIIB oxide, and 0.03-10 wt% of a transition metal oxide; wherein the main component is selected from at least one of Group IVB oxides; and the transition metal oxide is selected from at least one of Group VIB oxides, Group VIII oxides, Group IB oxides, and Group IIB oxides. The present invention rationally modifies the catalyst by introducing Group IIA metal elements, Group IIIB metal elements, and Group VIB, VIII, IB, and IIB metal elements into the main component, thereby suppressing carbon deposition of the catalyst in the alcohol dehydration reaction, improving the catalytic performance of the catalyst, and promoting the efficient conduct of the alcohol dehydration reaction to produce alpha-olefins.

The invention relates to a method for preparing formaldehyde by oxidizing dimethyl ether. According to the method, dimethyl ether is adopted as a reactant, and formaldehyde is prepared through an oxidation dehydration reaction under the action of an iron-molybdenum catalyst. The reaction conditions are as follows: the reaction is carried out in a fixed bed reactor, the reaction temperature is 280-340 DEG C, the reaction pressure is 0.1-0.3 MPa, and the volume space velocity of the dimethyl ether is 4500-25000h <-1 >. The method is characterized in that an iron-molybdenum material with a specific structure is used as a catalyst, the preparation structure of the catalyst is controllable, the cost is relatively low, the dimethyl ether is efficiently catalyzed to oxidize and generate formaldehyde in a high-selectivity manner, the highest selectivity of the formaldehyde can reach 85%, the highest conversion rate of methanol reaches 90%, and the stability is relatively good.

The invention belongs to the technical field of detergents, and particularly relates to a preparation method of a composite fluorescent whitening agent. The method comprises an acylation reaction, a sulfonation reaction, a carbonyl reduction reaction, a dehydration reaction and a sulfonic acid salification reaction. Compared with a commercially available fluorescent whitening agent such as CBS, the composite fluorescent whitening agent synthesized by the preparation method disclosed by the invention has similar application effects, but the preparation process disclosed by the invention is simple, low in cost, environment-friendly in route and environment-friendly in working environment.

The invention discloses a preparation method of titanium dioxide for high-ionic-conductivity battery electrolyte, and relates to the technical field of inorganic material preparation, and the preparation method comprises the following steps: S1, raw material mixing and esterification reaction; s2, reflux reaction and dehydration reaction; s3, neutralizing acidity and carrying out liquid-liquid layering; s4, double distillation purification; s5, performing ultrasonic-assisted dispersion; s6, carrying out sol-gel conversion; s7, carrying out gelation and vacuum drying; s8, performing low-temperature nitrogen presintering; s9, high-temperature oxidation calcination; and S10, performing nanocrystallization and interface modification. Through low-temperature nitrogen presintering and high-temperature oxidation calcination, the low-temperature presintering avoids structural damage, the high-temperature calcination optimizes the crystal performance, the purity, crystallinity and stability are remarkably improved, the high activity and long service life are achieved, and a key material support is provided for the fields of energy, environmental protection and the like.

The invention discloses a heat-resistant insulated power cable and a preparation method thereof, and relates to the technical field of insulated power cables, the heat-resistant insulated power cable comprises a centering mechanism, the centering mechanism is fixedly mounted on the outer surface of a wire core, and a gap is formed between the outer surface of the wire core and the centering mechanism and is filled with a heat-conducting insulating material. According to the heat-resistant insulated power cable and the preparation method thereof, the heat-shrinkable tube, the outer sleeve and the silica gel filling layer form a protective layer so that gas is not easy to leak, the spiral sheet embedded in the silica gel filling layer enables the cable to be not easy to break, compared with armoring, the spiral sheet enables the cable to be better in bendability, and the plurality of insulation mechanisms sleeve the surface of the longer wire core so that the heat-resistant insulated power cable is more stable in performance. The distance of the cavity gas flow channel is shortened, so that insulating gas in the cavity gas flow channel is easier to control and adjust, traditional flame-retardant coating coating is replaced, and the problem that a flame-retardant material is poor in flame-retardant effect during application due to toxic gas and dehydration reaction is solved.

The application discloses a continuous synthesis method of an amicarbazone intermediate 5-isopropyl-1,3,4-oxadiazole-2(3H)-ketone. The method comprises two continuous processes of hydrazinolysis and phosgenation: continuously feeding a mixture of isobutyric acid and a solvent, a mixture of hydrazine hydrate and a catalyst into a hydrazinolysis continuous reactor respectively, carrying out a warming reflux dehydration reaction, and obtaining an isobutyryl hydrazine solution shown in formula I; continuously feeding the isobutyryl hydrazine solution and phosgene into a phosgenation continuous reactor, carrying out a phosgenation reaction, and after distillation and desolventizing treatment of a reaction solution, obtaining 5-isopropyl-1,3,4-oxadiazole-2(3H)-ketone shown in formula II. The application has the advantages of simple reaction flow, high product yield, and significant production efficiency improvement, and is suitable for industrial large-scale production.

The application discloses a kind of high flame-retardant tpe materials and preparation method thereof, by polytetrahydrofuran, modified monomer and 4,4'-dicyclohexyl methane diisocyanate are reacted, chain extension is used with 1,4-butanediol, finally join flame-retardant additive, form branched structure, and the molecular structure of the pte material is branched structure, and molecular chain segment contains organic silicon composite organic phosphorus structure, when heat decomposition, can generate phosphoric acid, poly-metaphosphoric acid and other acidic substances, these acidic substances will catalyze pte molecule to occur dehydration reaction, accelerate its crosslinking, organic silicon chain segment will produce inorganic silicate or silicon-carbon, and then form a dense carbon layer on the surface of material, can heat insulation and oxygen isolation, prevent combustible gas to escape outward and oxygen diffusion inward, and slow down the further thermal decomposition of internal material, prevent carbon layer from being burnt through or collapse under high temperature, improve the durability of barrier, so that pte material has good flame-retardant effect.

The invention belongs to the technical field of synthesis of ester compounds, and particularly relates to a preparation method of 2, 6-dichloro-4-cyanobenzoic acid methyl ester, which comprises the following steps: by taking dimethyl 2-aminoterephthalate as a raw material, sequentially carrying out substitution reaction, deamination reaction, hydrolysis reaction, amidation reaction and dehydration reaction to obtain the 2, 6-dichloro-4-cyanobenzoic acid methyl ester. The 2, 6-dichloro-4-cyanobenzoic acid methyl ester is prepared by the method, and the yield reaches 59.28%. The N-chlorosuccinimide is used as a chlorine source to carry out substitution reaction on the 2-amino dimethyl terephthalate, so that the potential safety hazard caused by the traditional chlorination reagent is avoided, and the tert-butyl nitrite used in the deamination reaction avoids the potential safety hazard caused by the use of strong corrosive sulfuric acid; the amidation reaction is completed in one step by adopting a condensing agent, so that the complicated operation caused by firstly preparing acyl chloride and then carrying out condensation reaction is avoided, and therefore, the preparation method has the characteristics of safe preparation process, environment friendliness, simplicity in operation and the like under the condition of ensuring the product yield and purity.