358 results about "Dimethylamines" patented technology

A method for continuously producing m-xylylenediamine belongs to the technical field of organic synthesis and comprises the following steps: (1) mixing isophthalonitrile, toluene and liquid ammonia according to a mass ratio of 1: (3-5): (13-17) in a nitrogen atmosphere to form a reaction mixture; (2) heating the interior of a reaction bed containing a catalyst to 90-95 DEG C, continuously introducing hydrogen into the reaction bed, introducing the reaction mixture after the pressure intensity of the reaction bed is stable, and carrying out a catalytic hydrogenation reaction to generate a reaction product; and (3) carrying out gas-liquid separation on the reaction product, removing liquid ammonia from the liquid-phase product through an ammonia distillation process, and separating toluene and m-xylylenediamine through a rectification process to obtain m-xylylenediamine. According to the method, isophthalonitrile and hydrogen are used as raw materials, liquid ammonia and methylbenzene are used as reaction solvents, the raw materials and the reaction solvents are heated to 90-95 DEG C under the catalytic action of a catalyst for an exothermic reaction, m-xylylenediamine is generated through the reaction, and the reaction yield is larger than 99%.

The present invention relates to the field of the preparation of polyurethane elastic fibers, and relates to a preparation method for a bio-based polyurethane elastic fiber, comprising: preparing polyether polyol from sucrose, glycerol, dimethylamine and propylene oxide; adding a solvent, i.e., N,N-dimethylacetamide, and polyether polyol and polyisocyanate into a reaction tank, and adding p-Toluenesulfonyl semicarbazide and aluminum methylenebis(2,4-di-tert-butylphenoxy) phosphate to prepare a spinning solution; and subjecting the spinning solution to spinning and oil application by means of dry spinning technology to obtain the bio-based polyurethane elastic fiber. The present invention ensures that the properties of polyurethane elastic fibers do not deteriorate or are partially enhanced, while the cost and performance advantages are achieved.

The invention relates to the technical field of chemical synthesis, and discloses a preparation method of anhydrous N, N-dimethyl amino sulfuryl fluoride, which comprises the following steps: (1) introducing sulfuryl fluoride gas into a dimethylamine organic solution to carry out nucleophilic substitution reaction, and then adding triethylamine to obtain a mixed solution containing N, N-dimethyl amino sulfuryl fluoride; and (2) sequentially carrying out normal-pressure rectification and reduced-pressure rectification on the mixed solution containing the N, N-dimethyl amino sulfonyl fluoride to obtain the N, N-dimethyl amino sulfonyl fluoride. According to the method, water is not introduced in the whole process, the risk of water residue is avoided, and the prepared product is high in yield and purity.

The invention discloses a preparation method of a grafted polymer brush copolymer, which comprises the following steps: S1, mixing a styrene monomer, N-4-vinyl phenyl-N, N-dimethylamine, toluene and AIBN, heating, and reacting to generate a first section of polymer; and S2, mixing the first-section polymer with an acrylate monomer and an imide compound, and continuously reacting under an illumination condition to obtain the polymer brush copolymer. AIBN can be decomposed at high temperature to generate free radicals, polystyrene monomers are initiated to polymerize, and a first-section polymer is formed. The imide compound and a nitrogen-containing initiation site form a charge transfer complex under an illumination condition. The charge transfer complex can be dissociated to generate free radicals formed by nitrogen-containing initiation sites, and then the free radicals formed by the nitrogen-containing initiation sites initiate polymerization of acrylate monomers to obtain a grafted polymer brush copolymer. The preparation method is simple in reaction condition, simple and convenient to operate and suitable for industrial large-scale production.

The invention discloses an anticorrosive coating composition based on a nano hybrid and a preparation method of the anticorrosive coating composition, and relates to the technical field of powder coatings. Comprising the following components in parts by weight: 60-70 parts of fluorosilicone modified epoxy resin, 8-10 parts of an aminoethylated acrylic polymer, 4-8 parts of a functionalized nano hybrid, 4-6 parts of a curing agent, 0.3-1.2 parts of an accelerant, 1-2 parts of benzoin, 2-4 parts of a functional aid, 10-15 parts of a micron-sized filler and 1-2 parts of a coupling agent. The curing agent is prepared by compounding dicyandiamide, bicyclo [2.2. 1] heptane dimethylamine and 3, 5-diamino-1, 2, 4-triazole according to a mass ratio of (3 to 5): 1: (0.8 to 1.2). The coating composition is high in adhesive force and excellent in impact resistance and corrosion resistance.

The invention discloses a method for synthesizing N, N-dimethylformamide through electrochemical catalytic conversion of dimethylamine. The synthesis method provided by the invention comprises the following steps: by taking dimethylamine as a single substrate, carrying out in-situ electrochemical oxidation reaction to obtain N, N-dimethylformamide; a working electrode used in the in-situ electrochemical oxidation reaction is a composite electrode loaded with a co-oxide Cr2WO6 crystal. According to the synthesis method provided by the invention, only dimethylamine is used as a substrate, and the substrate is few in variety and low in concentration, so that the raw material cost is greatly reduced, and the damage of the high-concentration substrate to a catalyst and reaction equipment is reduced; in addition, the method is high in Faraday efficiency, has important practical application value for efficient resource utilization of dimethylamine, and has far-reaching significance in the aspect of carbon neutralization at present.

The present application relates to a kind of dimethylamine piperidine continuous synthesis dimethylamine piperidine method of oxy group, by using reaction raw material mixed solution into continuous flow packed bed reaction zone, i.e.catalyst layer;Reaction temperature is 20-80 ℃, normal pressure, feed liquid is the mixture of dimethylamine piperidine, hydrogen peroxide and deionized water, oxidation is carried out on the catalyst layer of continuous flow packed bed adiabatic reactor to make dimethylamine piperidine into dimethylamine piperidine oxy group, realize the continuous preparation of dimethylamine piperidine oxy group;The obtained reaction liquid is quenched, then filtered to remove solid particle quenching agent, vacuum distillation to remove water and vacuum rectification treatment obtain high-purity dimethylamine piperidine oxy group;The process scheme overcomes the series of deficiencies in the previous preparation process, such as complicated steps, low product purity, low production capacity in unit production time, realizes the continuous preparation of high-purity dimethylamine piperidine oxy group, with the characteristics of efficient, safe, green manufacturing.

The present application belongs to the technical field of protective coating, and relates to a protective coating with reverse enhanced adhesion, a preparation method and application thereof. The protective coating is composed of component A and component B. The preparation raw materials of component A include water-based epoxy resin emulsion, cashew phenol glycidyl ether, wetting penetrant and defoaming agent. The preparation raw materials of component B include phenolic amine curing agent, alicyclic amine curing agent, dopamine, 2,4,6-tris(dimethylaminomethyl)phenol and pigment filler. The dopamine and the phenolic amine curing agent and the alicyclic amine curing agent are grafted under the action of 2,4,6-tris(dimethylaminomethyl)phenol to form a modified curing agent. The coating has low requirements for surface treatment, high adhesion in dry and humid environments and presents the characteristics of "reverse enhanced adhesion".

The invention relates to a method for producing methylamine by a generally exothermic gas-phase reaction of methanol and ammonia as reactants in the presence of a heterogeneous catalyst at a pressure in the range of 15 to 35 bar. The reactants are evaporated in one or more heat exchangers and superheated prior to being fed to the reactor, wherein the heat exchangers in turn are heated with a stream of hotter product gas from the reactor. In addition to methylamine (monomethylamine, dimethylamine, and trimethylamine), the product gas stream contains unconverted reactants, water, and any other reaction by-products. To control the reactor inlet temperature and limit it to a temperature in the range of 350 DEG C to 410 DEG C, a suitable quenching liquid is introduced into the hot product gas stream prior to feeding the hot product gas stream to a heat exchanger for heating the reactants. Evaporation and overheating of the added quenching liquid removes the corresponding amount of energy extracted from the hot product gas stream, with the result of efficient and rapid cooling of the hot product gas stream. As a result, the temperature difference between the cold side and the hot side of the heat exchanger is small, which means less energy is transferred to the reactant stream, and thus its reactor inlet temperature can be adjusted or limited.

The invention discloses a method for hydrolyzing dimethylformamide and recovering dimethylamine, which comprises the following steps: mixing dimethylformamide wastewater with alkali liquor, and adjusting the pH value of the wastewater to 11.5-12 to obtain adjusted wastewater; heating the adjusted wastewater to 70-80 DEG C, and carrying out hydrolysis reaction to obtain hydrolyzed wastewater, wherein the hydraulic retention time is 3-4 hours; carrying out steam stripping deamination on the hydrolyzed wastewater to obtain steam containing dimethylamine and deaminated wastewater; the steam containing dimethylamine is subjected to condensation and gas-liquid separation, gas-phase dimethylamine and condensate are obtained, and the condensate flows back to the steam stripping amine removal step; the gas-phase dimethylamine is absorbed by a low-temperature absorption liquid to obtain a dimethylamine aqueous solution product, and tail gas generated in the absorption process is purified. According to the method, the residual concentration of DMF can be reduced to be extremely low (1t: 15 mg / L), the biotoxicity is effectively relieved, and good conditions are created for subsequent anaerobic and aerobic biochemical treatment of wastewater.

The invention relates to a method for green, mild and efficient synthesis of methylamine hydrochloride based on photocatalysis. According to the method, methanol and ammonium chloride which are wide in source and low in price are used as raw materials, under the anaerobic condition, a Pd / TiO2 photocatalyst is adopted for a photocatalytic reaction, and target methylamine hydrochloride products including monomethylamine hydrochloride, dimethylamine hydrochloride and trimethylamine hydrochloride are synthesized in one step. Compared with traditional industrial synthesis, the photocatalysis technology has the advantages of mild reaction conditions, simplicity and convenience in operation, environmental friendliness and the like, provides an efficient and feasible way for green synthesis of methylamine hydrochloride, and has a wide application prospect.

This invention discloses a highly efficient catalytic synthesis process for nicotinamide intermediates using the field of organic synthesis technology. The process includes: adding appropriate amounts of dichloronicotinic acid, organic solvent, lanthanum-doped composite metal fluoride-diatomaceous earth supported catalyst, and encapsulated 4A molecular sieve to a reaction vessel under nitrogen protection; purging with nitrogen, heating, and stirring; introducing anhydrous dimethylamine gas, controlling the pressure, and continuing stirring; after the reaction is complete, washing with sodium bicarbonate aqueous solution, washing with deionized water, drying, concentrating, and recrystallizing to obtain the target product. The lanthanum-doped composite metal fluoride-diatomaceous earth supported catalyst prepared by this invention is recyclable, has mild reaction conditions, high product yield, is environmentally friendly, and suitable for industrial production.

The application belongs to the field of chemical industry, and particularly relates to a preparation method of N,N,N',N'-tetramethyl diacrylamine, which comprises the following steps: hydrogenation reaction is carried out by introducing hydrogen into an amine group propyl cyanide compound, a dimethylamine aqueous solution and a catalyst; under the protection of inert gas, solid-liquid separation (filtration) is carried out on the obtained hydrogenated material, so that a filtrate and a filter cake are obtained; and the filtrate is subjected to rectification, so that N,N,N',N'-tetramethyl diacrylamine (2(DMAP)A) is obtained. The application has the advantages of simple process, mild conditions, green environmental protection, high product yield and facilitation of industrial production.

The present invention relates to ophthalmic formulations in which a synergistic combination of three different types of disinfectants (a polybiguanide compound, a quaternary ammonium compound and an antifungal / anti-acanthamoeba compound), in particular a combination of polyhexamethylene biguanide, polyquaternium-1 and myristoylaminopropyl dimethylamine, high concentrations of hyaluronates are enabled to provide better comfort and support for corneal health without compromising antimicrobial efficacy. The novel ophthalmic formulations support the use of hyaluronates at concentrations greater than 7.5 times as high as currently commercially available multi-purpose disinfectants.

The present application belongs to the field of polymer materials, and particularly relates to a self-toughened epoxy resin with high temperature resistance and a preparation method thereof. The modifier is a multifunctional epoxy resin containing a polyetherimide structure. The modifier is dissolved and blended with a bisphenol A type epoxy resin. The curing agent comprises one or more of methyl nadic anhydride, methyl tetrahydrophthalic anhydride, methyl hexahydrophthalic anhydride, dodecenyl succinic anhydride and pyromellitic anhydride. The curing accelerator comprises one or more of dimethylaminomethylphenol, ortho-hydroxybenzyl dimethylamine, 2,4,6-tris(dimethylaminomethyl)phenol, triethylamine and triethanolamine. The multifunctional epoxy resin containing a polyetherimide structure not only has good solubility in the bisphenol A type epoxy resin, but also can participate in the curing reaction of the bisphenol A type epoxy resin, so that the toughness and temperature resistance of the bisphenol A type epoxy resin can be significantly improved.

The present application belongs to the technical field of pharmaceutical therapy, and particularly relates to an amide-substituted tryptophan ketone derivative, a preparation method and application thereof. The structural formula of the tryptophan ketone derivative is shown in formula (A) or formula (B). In the formula, n=1 or 2, and R is any one of dimethylamine group, diethylamine group, morpholine group, 1-methylpiperazine group, cyclopropylamine group and 4-hydroxypiperidyl group. The compound can selectively inhibit the activity of acetylcholinesterase, and has the potential to develop into a drug for treating Alzheimer's disease due to the abilities of self-aggregation and the like. 1‑42 ​

The invention relates to a method for preparing (cyclopentadienyl) tris (dimethylamino) hafnium by using nuclear magnetic control, which comprises the following steps: S1, carrying out heating reflux reaction on hafnium tetrachloride, cyclopentadiene and dimethylamine in the presence of n-butyllithium and n-hexane, and after reacting for a certain time, taking supernate to detect a nuclear magnetic hydrogen spectrum; s2, calculating the ratio a of the integral area of the characteristic peak A to the integral area of the characteristic peak B according to the nuclear magnetic hydrogen spectrum, judging whether a is in a target range or not, if a is in the target range, terminating the reaction, separating a liquid phase, distilling and collecting a crude product; and if a value is greater than the maximum value of the target range, adding cyclopentadiene into the reaction system to continue the reaction, and if a value is less than the minimum value of the target range, continuing the reaction until the ratio of the integral area of the characteristic peak A to the integral area of the characteristic peak B in the nuclear magnetic hydrogen spectrum of the reaction supernatant is within the target range, terminating the reaction, separating the liquid phase, distilling and collecting a crude product. The method can effectively improve the safety of the production process, the raw material conversion rate and the product purity.

The invention belongs to the field of electrochemical synthesis, and particularly discloses a method for synthesizing N, N, N ', N'-tetramethyl methylenediamine by directly utilizing a dimethylamine aqueous solution through electrochemical amine methylenation. According to the method, a dimethylamine aqueous solution is used as a raw material, and an electrochemical amine methyleneation reaction of dimethylamine is carried out on an anode loaded with a carbon material catalyst in an electrically driven oxidation manner, so that synthesis of N, N, N ', N'-tetramethyl methylenediamine is realized. Different from the existing dimethylamine and formaldehyde condensation method and dimethylamine and methanol electrosynthesis method, the method disclosed by the invention directly adopts the industrial dimethylamine aqueous solution as a raw material to synthesize N, N, N ', N'-tetramethyl methylenediamine, so that the process flow is simplified, and the yield is high. The method has the characteristics of mild process conditions, high system stability, few byproducts, greenness, safety, low cost and suitability for industrial application. The method has wide application potential in the fields of electrochemical organic synthesis, energy storage, pharmaceutical chemical industry and the like.

The invention belongs to the technical field of chemical synthesis of semiconductor materials, and particularly relates to a synthesis method of tetra (dimethylamino) titanium, which comprises the following steps: (1) reacting titanium tetrachloride with dimethylamine to generate an intermediate TiClx [N (CH3) 2] 4-x, where x is an integer from 0 to 4; (2) reacting dimethylamine with an organic metal lithium reagent to synthesize lithium dimethylamino (LiN (CH3) 2); and (3) reacting the intermediate obtained in the step (1) with lithium dimethylamino obtained in the step (2) to obtain tetra (dimethylamino) titanium. By adopting a step-by-step reaction strategy, the dependence on expensive n-butyllithium is fundamentally reduced, the raw material cost is remarkably reduced, meanwhile, the reaction process is optimized by generating an intermediate, the product yield is greatly improved, the generation of byproducts is effectively reduced, and the product purity is improved.

The application provides a preparation method of N,N-dimethylformamide (DMF). The method uses carbon dioxide, hydrogen and dimethylamine as reaction raw materials, and N,N-dimethylformamide is prepared through N-formylation of carbon dioxide under the action of a catalyst. The method uses an oxide supported transition metal as the catalyst, the catalyst composition and the preparation method are simple and low in cost, the reaction is carried out in a fixed bed reactor, the reaction continuity is good, the catalyst and the reaction system are easy to separate, the catalyst is convenient to recycle, the reaction condition is relatively mild, the conversion rate of dimethylamine and the selectivity of DMF are high, and the method provides an economic, environment-friendly and effective way for the synthesis of DMF.

The invention discloses gemini quaternary ammonium salt type sulfur-containing polyester and a preparation method and application thereof.The preparation method comprises the steps that dimethylamino diacrylate and halogenated alkyl quaternary ammonium salt are subjected to a substitution reaction, and gemini quaternary ammonium salt type diacrylate is obtained; then, the gemini quaternary ammonium salt type diacrylate and alkyl dithiol are subjected to a sulfydryl-alkene click polymerization reaction, and the gemini quaternary ammonium salt type sulfur-containing polyester is obtained. According to the gemini quaternary ammonium salt type sulfur-containing polyester as well as the preparation method and the application thereof, the gemini quaternary ammonium salt type sulfur-containing polyester has excellent inhibition and killing activity on helicobacter pylori and has good blood compatibility and relatively low cytotoxicity.

The application discloses a preparation and purification process of high-purity low-chlorine tetra (dimethylamino) tin, and belongs to the technical field of synthesis of semiconductor electronic chemicals. The three core technologies of accurate control of the molar ratio of chlorine and tin 2.00-2.05, low-temperature segmented synthesis of intermediates at-78 DEG C to-60 DEG C, and three-stage gradient low-temperature purification at 40 DEG C to 60 DEG C are used to synthesize the product with high-purity anhydrous stannous chloride and low-moisture anhydrous dimethylamine as raw materials, and double alkali reagents are used to synthesize the product, so that the risk of high-temperature decomposition is avoided in the whole process, and chlorine ions and metal impurities are deeply removed. The product has a purity of greater than or equal to 99.99%, chlorine ions are less than 10 ppm, single metal impurities are less than 1 ppm, total metal impurities are less than or equal to 5 ppm, moisture is less than 20 ppm, and the comprehensive yield is 55%-60%. The product is suitable for EUV dry photolithography, electron beam CVD and tin-based ALD processes. The process parameters of the application are quantitatively controlled in a narrow range, the technical barriers are strict, and the application has a good authorization prospect.

The present invention relates to ophthalmic formulations wherein a synergistic combination of three different classes of disinfectants (a multimeric biguanide compound, a quaternary ammonium compound and an antifungal / anti-acanthamoeba compound, in particular a combination of polyhexamethylene biguanide, Polyquaternium-1 and myristamidopropyl dimethylamine) enables the use of high concentrations of hyaluronate for providing better comfort and support of corneal health without compromising antimicrobial efficacy. The novel ophthalmic formulations support the use of more than 7.5 times higher concentrations of hyaluronate than are present in currently marketed multi-purpose disinfection solutions.

The invention belongs to the technical field of biomolecule detection, and particularly relates to a quantitative analysis method for sialic acid. According to the method, a basic type sialic acid standard substance is used as an internal standard substance, dimethylamine and deuterated dimethylamine are used as labeling reagents, amido bonds are generated between the labeling reagents and carboxyl groups in the internal standard substance and a biological sample, sialic acid is labeled at the same time, the samples with light and heavy labels are mixed, and the mixture passes through a reduction end of 3-nitrophenylhydrazine derivative sialic acid. After detection is completed through a liquid chromatography-mass spectrometry method, absolute quantitative analysis can be performed on sialic acid in a biological sample on the basis of combined use of an internal standard method and an external standard method. As O-acetylated sialic acid and non-O-acetylated sialic acid of the same type can generate similar secondary mass spectrums and same quantitative ions, absolute quantitative analysis can be approximately performed on O-acetylated sialic acid by using the method and the device.

The application provides a nitrogen-doped carbon-coated catalyst, a preparation method thereof and a method for preparing m-xylylenediamine from m-xylylene cyanide, the nitrogen-doped carbon-coated catalyst is a core-shell structure with a metal active component as an inner core and a nitrogen-doped carbon material as a coating layer, and the loading amount of the metal active component is 9-50 wt% based on 100 wt% of the mass fraction of the nitrogen-doped carbon-coated catalyst. The nitrogen-doped carbon-coated catalyst provided by the application does not need to be activated and can directly be used to show excellent catalytic activity, selectivity and stability for the hydrogenation reaction of m-xylylene cyanide, the selectivity and yield of m-xylylenediamine can be significantly improved under relatively mild reaction conditions, and the catalyst is easy to separate from the product and convenient for recycling.

The invention relates to the field of textile printing materials, and discloses a preparation method of water-based digital printing bottoming white adhesive cement, which comprises the following steps: mixing water-based acrylate emulsion with an auxiliary agent and a macromolecular quaternary ammonium salt color fixing agent to obtain a premix; mixing the premix with filling powder to obtain dispersion liquid; and adding a curing agent and a thickening agent into the dispersion liquid and mixing. The macromolecular quaternary ammonium salt color fixing agent is prepared by reacting an organic silicon modified allylamino phosphorus-containing bromine substituent and bis (dimethylamino) phosphoric acid hydrogenated cardanol ester; the organic silicon modified allylamine phosphorus-containing bromine substituent is prepared by preparing the allylamine phosphorus-containing bromine substituent from allylamine, phenyl dichlorophosphate and 2-bromoethylamine hydrobromide as raw materials and then reacting the allylamine phosphorus-containing bromine substituent with heptamethyltrisiloxane. The white rubber cement prepared by the preparation method is bright in color and clear in pattern, can be recycled and reused, and has the advantages that the white rubber cement is easy to prepare, the cost is low, and the application prospect is wide. The color fixing fastness, the flame-retardant and fire-proof performance, the net blocking prevention performance and the hand feeling comfort degree are good.

The invention discloses a method for high-selectivity separation of low-concentration coal bed gas by a hydrate method using tri-n-butylphosphine oxide as a thermodynamic accelerant. The method comprises the following steps: carrying out hydrate generation and separation on low-concentration coal bed gas in a 5 wt% tri-n-butyl phosphine oxide solution under the conditions of 277.15 K and 4 MPa, and increasing the methane concentration from 30.07 mol% to 88.17 mol% after purification; the separation performance is improved by further adding 0.5 wt% of a kinetic accelerator (preferably cocamidopropyl dimethylamine), and experimental results show that the methane concentration after single-stage separation can be improved from 30.07 mol% to 92.84 mol%, the separation factor reaches 40.93, and the system is in slurry dispersion and has no wall climbing phenomenon. The method is safe to operate, the accelerant can be recycled, and the method is suitable for efficient purification and resource utilization of methane in mixed gas such as low-concentration coal bed gas, biogas and coke-oven gas.

The invention belongs to the field of water treatment, and more particularly to a positively charged quaternary ammonium salt polymer catalyst and its preparation method and application. The catalyst provided by the present invention is made of a positively charged quaternary ammonium salt precursor through polymerization and anion exchange, and the positively charged quaternary ammonium salt precursor is the reaction product of acrylate and halogenated alkane; the acrylate is one or more of dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate and 3 (dimethylamino) ethyl acrylate; the halogenated alkane is one or more of undecane bromide, dodecane bromide, tetradecane bromide, hexadecane bromide, eicosane bromide, dodecane chloride, tetradecane chloride and hexadecane chloride. The catalyst provided by the present invention has good stability and antibacterial properties, can efficiently and selectively catalyze the degradation of organic pollutants by peroxide, has important practical significance for removing wastewater rich in organic pollutants, and has a wide range of applications in water pollution control and water environment restoration.