431 results about "Dimethylacetamide" patented technology

The invention discloses a fluralamide moxidectin drop and a preparation method thereof, and relates to the technical field of veterinary drugs. The drop is prepared from the following components in parts by weight: 26 to 26.5 parts of fluralan, 1.32 parts of moxidectin, 0.10 part of butylated hydroxytoluene, 29.5 to 30.5 parts of dimethylacetamide, 19.5 to 20 parts of tetrahydrofuran polyethylene glycol ether, 13 to 13.5 parts of diethyl toluamide, 8.5 to 9.3 parts of acetone and 1.0 to 1.5 parts of ethanol. The invention has the effects of improving the stability, permeability and lasting effect of the medicine.

The invention relates to the technical field of layered composite fabrics, in particular to a bio-based antibacterial fiber fabric and a preparation method thereof. The preparation method comprises the following steps: carrying out a reaction on diisocyanate, polyether polyol, bio-based polyester polyol and hexamidine dihydroxyethyl sulfonate in N, N-dimethylacetamide, so as to obtain a polyurethane prepolymer solution; 2-(4-aminophenyl)-5-aminobenzimidazole and amino-modified nano-zinc oxide are sequentially added into the polyurethane prepolymer solution for a reaction, a prepared polyurethane spinning solution is subjected to dry spinning to prepare polyurethane fibers, and then the polyurethane fibers are sequentially spun into yarn and fabric; the bio-based nylon is subjected to melt spinning to obtain bio-based nylon fibers, and the bio-based nylon fibers are sequentially spun into yarns and fabrics; the bio-based antibacterial fiber fabric is prepared by taking a polyurethane fabric as an inner-layer fabric and taking a bio-based chinlon fabric as an outer-layer fabric, and the fabric is good in antibacterial performance and moisture absorption performance.

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 application discloses a preparation method of a hydrophilic oil-water separation anti-pollution membrane and the anti-pollution membrane and application thereof, and prepares MNRs material; the MNRs material is dispersed in dimethylacetamide, is uniformly stirred, polyvinylpyrrolidone is added, and stirring is continued, and a first mixture is obtained through ultrasonic treatment; the first mixture is mixed with polyvinylidene fluoride to obtain a second mixture, and the second mixture is stirred; the treated second mixture is dip-coated on a carrier, the dip-coated carrier is treated in deionized water to obtain an ultrafiltration membrane; the ultrafiltration membrane is soaked in a tea polyphenol solution with a Tris-HCl buffer solution, and is shaken to obtain the hydrophilic oil-water separation anti-pollution membrane. The hydrophilic oil-water separation anti-pollution membrane has excellent separation efficiency and flux recovery rate for four different oil-water mixtures of kerosene, gasoline, edible oil and n-hexane. The preparation process of the oil-water separation membrane is simple, the cost is low, and the reaction condition is mild; when the oil-water separation membrane is applied to organic wastewater separation, the oil-water separation membrane has the advantages of high efficiency, good removal performance and good recycling performance.

The invention is applicable to the field of preparation of modified polyimide materials, and provides a transparent polyimide film material with corona resistance and a preparation method thereof, the transparent polyimide film material comprises the following raw materials: nano SiO2 particle-N, N-dimethylacetamide dispersion liquid, a diamine monomer, a benzoxazine monomer and a dianhydride monomer; wherein the N, N-dimethylacetamide dispersion liquid contains nano silicon dioxide (the particle size is about 10-20 nm, and the mass fraction is 30 wt% + / -5 wt%). The transparent polyimide film with corona resistance is prepared by uniformly dispersing nano silicon dioxide particles and benzoxazine in a polyimide matrix by adopting an in-situ polymerization method, the film realizes excellent corona resistance of a material, and meanwhile, the preparation method has the advantages of simple process, energy conservation, environmental protection, high efficiency and the like.

A method for catalyzing selective oxidation of 5-hydroxymethylfurfural by ion-doped birnessite belongs to the field of chemical engineering, and comprises the following steps: adding an ion-doped birnessite type catalyst into a solvent, and catalyzing 5-hydroxymethylfurfural to prepare 2, 5-furandicarboxaldehyde and 2, 5-furandicarboxylic acid in the atmosphere of air or oxygen at the temperature of 25-240 DEG C, wherein the solvent is water, methanol, ethanol, acetonitrile, dichloromethane, N, N-dimethylformamide, N, N-dimethylacetamide and the like. The method is simple, few in by-products and environmentally friendly. By adopting ion-doped birnessite as the catalyst, the method has the advantages of economy, environmental protection, mild conditions, high selectivity, easiness in recovery of the catalyst and the like; the ion-doped birnessite catalyst can efficiently and highly selectively catalyze oxidation of 5-hydroxymethylfurfural to prepare 2, 5-furandicarboxaldehyde, catalytic materials are easy to separate, the production cost is low, and the ion-doped birnessite catalyst has remarkable technical and economic effects and application prospects.

The invention discloses a preparation method of a vanadium battery electrolyte oxidation corrosion resistant composite membrane, which comprises the following steps: S1, uniformly dispersing graphene oxide nanosheets on the surface of an SPEEK (sulfonated polyether ether ketone) matrix by using sulfonated polyether ether ketone as a substrate to obtain an SPEEK / GO (graphene oxide) substrate; s2, treating the SPEEK / GO substrate in oxygen plasma treatment equipment, and ultrasonically cleaning the SPEEK / GO substrate with isopropanol for 10-20 minutes; s3, dissolving polybenzimidazole in N, N-dimethylacetamide (the concentration is 3-5wt%), and magnetically stirring until the polybenzimidazole is completely dissolved; the preparation method comprises the following steps: adding TiO2 nanoparticles (the particle size is 20-25nm, and the TiO2 nanoparticles are pretreated by a silane coupling agent KH-570) according to the mass ratio of 15-20%, ultrasonically dispersing and carrying out ice bath to obtain PBI-TiO2 dispersion liquid; s4, the SPEEK / GO substrate treated in the step S1 is vertically immersed in PBI-TiO2 dispersion liquid, the final coating thickness is 1.5 + / -0.2 [mu] m, and a pretreated film is obtained; and S5, carrying out hot pressing on the pretreated membrane by using a hot press, and then carrying out gradient cooling to room temperature to obtain the final composite membrane. The vanadium battery is better in vanadium resistance and corrosion resistance and suitable for high-power-density vanadium batteries.

The application relates to a preparation method of a hollow fiber membrane composite thermal insulation material, which comprises the following steps: adding 18-22% of polyurethane, 4-8% of polyethylene glycol 2000 and 72-76% of N,N-dimethylacetamide into a spinning reaction kettle to mix, stir and defoam to prepare homogeneous casting solution; based on a non-solvent induced phase separation method, the homogeneous casting solution is coated on the surface of a polyester braided tube through a spinneret by adopting a concentric circle composite spinning technology, is gathered on a spinning wheel after a coagulation bath to form a reinforced polyurethane hollow fiber membrane assembly which is arranged in parallel and obliquely crosses and is mutually bonded, and the fiber membrane assembly is hot-pressed to prepare the hollow fiber membrane composite thermal insulation material under the conditions of a temperature of 60-150 DEG C and a pressure of 120-470 MPa. Since the coating layer and the braided tube are both through porous structures, the prepared composite material has good air permeability.

The invention relates to the field of composite ultrafiltration membranes, in particular to a GO / PVDF composite ultrafiltration membrane for MBR and a preparation method of the GO / PVDF composite ultrafiltration membrane. The GO / PVDF composite ultrafiltration membrane is prepared by adopting 18% of polyvinylidene fluoride as a membrane base material, 6% of polyvinylpyrrolidone as a pore-foaming agent, 0-2% of graphene oxide as a modifier and the balance of N, N-dimethylacetamide as a solvent through an impregnation phase inversion method. The GO with low mass fraction is added into the section of the membrane to form a large and thick finger-shaped pore structure, the filtration resistance of membrane pores is reduced, the filtration flux, hydrophilicity, permeability and interception performance of the membrane are improved, the method is simple to operate, the prepared finished product is excellent in performance, and the research and application expansion of a membrane modification technology are promoted.

The invention discloses a preparation method of a polyimide-boron nitride nanosheet heat-conducting composite film. The preparation method comprises the following steps: firstly, dispersing boron nitride nanosheets into N, N-dimethylacetamide containing poly (diallyldimethylammonium chloride) to prepare slurry; meanwhile, 4, 4 '-diaminodiphenyl ether reacts with pyromellitic dianhydride to prepare a polyamide acid solution. And mixing the two materials, forming a layered structure through vertical and horizontal temperature gradients by adopting a bidirectional freezing casting technology, and freezing by liquid nitrogen to obtain the aerogel in oriented arrangement. And performing hot pressing and step-by-step thermal imidization treatment to obtain the heat-conducting composite film. According to the method, the highly-oriented arrangement of boron nitride nanosheets is constructed through bidirectional freezing casting, and the composite film has excellent heat-conducting property and keeps good mechanical strength and flexibility in combination with the surface modification effect. The process is simple and controllable, and is suitable for the fields of flexible electronics, 5G heat dissipation, battery thermal management and the like.

The present invention belongs to the technical field of fabric color fixing agents and provides a novel acidic color fixing agent free of bisphenol S and a preparation method thereof; the acidic color fixing agent is composed of the following components in parts by weight: 15-25 parts of water, 10-15 parts of phenol, 15-25 parts of dimethylacetamide, 2-5 parts of sodium sulfite, 10-15 parts of acetic acid, 5-7 parts of concentrated sulfuric acid, 15-20 parts of acrylic acid, 2-5 parts of ethylene glycol dimethyl ether, and 1-3 parts of sorbitol; the preparation method comprises the following steps: mixing a formula amount of phenol, dimethylacetamide, acrylic acid, acetic acid, and sodium sulfite, heating, adding concentrated sulfuric acid to react, cooling, adding a formula amount of water, and adding a formula amount of ethylene glycol dimethyl ether and sorbitol to obtain the product. Compared with the prior art, the present invention does not contain bisphenol S, has a good color fixing effect, can effectively improve various fastnesses such as water fastness, perspiration fastness, and seawater resistance, has little effect on the color change of the fabric after treatment, and has good tolerance to hardness ions.

The invention discloses a compound fluralana external preparation for dogs, a preparation method and application, belongs to the technical field of veterinary drugs, and solves the problems that an existing preparation is poor in skin surface permeability, a solvent is easy to volatilize, and use experience and drug effect exertion are influenced. The preparation is prepared from the following raw materials: fluralana, moxidectin, ethyl butylacetamidopropionate and N, N-dimethylformamide. The preparation method comprises the following steps: adding N, N-dimethylacetamide, acetone, an auxiliary adjuvant, a transdermal penetration enhancer, an antioxidant and a surface film-forming agent; according to the invention, the combination of the fluralab and the moxidectin can play a synergistic effect and expand an anti-parasitic spectrum so as to achieve an internal and external driving effect; both the fluralab and the moxidectin belong to high-fat-soluble substances, parasites can be quickly repelled and killed by adding novel adjuvant natural parasite expelling ingredients, and meanwhile, the skin permeability can be improved by adding the efficient transdermal penetration enhancer, and the risk that medicine residues are licked by pets is reduced.

The invention discloses a preparation method and an application of a flower-like Mg-Al LDH (layered double hydroxide) modified polydimethylsiloxane / polyethersulfone composite membrane. The preparation method comprises the following steps: dissolving polyethersulfone in N, N-dimethylacetamide, scraping a membrane, and soaking the membrane in deionized water; the preparation method comprises the following steps: dissolving PDMS in an isooctane solvent, adding LDH with different concentrations, continuously stirring until LDH is completely dispersed, adding PDMS, a cross-linking agent and a catalyst into the cross-linking agent and the catalyst according to a mass ratio of 10: 2: 1, and preparing the coating by adopting a wet film dip-coating method. And coating to obtain the modified composite membrane. The method is mainly applied to preparation of gas-liquid two-phase gas separation so as to obtain a composite membrane material with high CO2 / O2 selectivity and high gas permeability. Meanwhile, the method is simple in preparation process, the raw materials are cheap and easy to obtain, the LDH modified composite membrane can effectively improve the gas permeability and selectivity of the material, and a new preparation thought is provided for preparing a good CO2 gas separation membrane.

The invention discloses a method for rapidly synthesizing MOFs (Metal-Organic Frameworks) derived sulfide CoS / Co-MOF (Metal-Organic Frameworks). The synthesis method comprises the following steps that a Co-MOF precursor is obtained through a solvothermal method, then the Co-MOF precursor is mixed with thioacetamide, absolute ethyl alcohol and dimethylacetamide, and the MOFs derivative sulfide CoS / Co-MOF composite material is obtained through the solvothermal method. Compared with a traditional pyrolysis method, the method is easy and convenient to operate and mild in condition, the reaction time is greatly shortened, and in addition, a series of electrochemical tests (LSV, CV, EIS and CP) prove that the CoS / Co-MOF composite material shows excellent OER performance and is an excellent OER catalyst.

The invention relates to the technical field of non-woven materials, in particular to a polyether-ether-ketone resin special material for melt-blown non-woven fabric, a preparation method of the polyether-ether-ketone resin special material, the melt-blown non-woven fabric and a manufacturing method of the melt-blown non-woven fabric. The preparation method of the special material for the polyether-ether-ketone resin comprises the following steps: in an inert gas atmosphere, heating a first mixture obtained by mixing 4, 4 '-difluorobenzophenone and dimethylacetamide to a first temperature to obtain a first mixture at the first temperature; sequentially adding alkali carbonate and hydroquinone into the first mixture at the first temperature, then performing sectional heating treatment, and performing washing treatment to obtain polyether-ether-ketone resin; the polyether-ether-ketone resin is placed in a screw extruder to be subjected to melt extrusion granulation, and the polyether-ether-ketone resin is obtained after filtering treatment. The polyether-ether-ketone resin special material with ultrahigh melt flowability and low apparent viscosity can be prepared by the method provided by the invention, and can meet the requirements of manufacturing melt-blown non-woven fabrics.

The invention relates to a polyimide composite film for realizing high-dispersion carbon nanotubes through chemical anchoring and a preparation method of the polyimide composite film, which are used for solving the problems that carbon nanotubes in the existing carbon nanotube / polyimide composite material are easy to agglomerate, poor in interfacial compatibility and low in grafting efficiency. The preparation method comprises the following steps: S1, ultrasonically dispersing aminated carbon nanotubes in anhydrous dimethylacetamide to obtain a stable dispersion liquid; s2, slowly dropwise adding pyromellitic dianhydride into the stable dispersion liquid under an ice bath condition, and enabling the pyromellitic dianhydride to react with the aminated carbon nanotubes under the assistance of triethylamine to form anchor points; s3, adding a diamine monomer 4, 4 '-diaminodiphenyl ether, and gradually adding the residual pyromellitic dianhydride to carry out in-situ polymerization; and S4, preparing a wet film by adopting a curtain coating or spin coating method, and carrying out step-by-step thermal imidization at 80-300 DEG C to obtain the covalent composite film. Controllable covalent connection of the carbon nanotubes and pure polyimide chain segments can be achieved on the molecular level, and therefore the composite film with excellent heat conductivity, electromagnetic shielding performance and mechanical performance is obtained.

The application discloses a preparation method of superfine nanofiber antibacterial and mosquito-repellent high-efficiency low-resistance air filtration membrane, which comprises the following steps: dissolving cellulose acetate, cinnamyl aldehyde and polyhexamethylene biguanide hydrochloride in a solvent, fully stirring to form a spinning solution, wherein the solvent is a mixed solution of acetone, N, N-dimethylacetamide and water; and performing electrostatic spinning on the spinning solution to obtain the superfine nanofiber antibacterial and mosquito-repellent high-efficiency low-resistance air filtration membrane. The manufacturing steps of the application are simple and not complicated; cellulose acetate has excellent mechanical properties, hydrophobicity and thermal stability, and is an ideal material for air filtration membrane; the liquid property of cinnamyl aldehyde can effectively dilute cellulose acetate, so that the overall binding energy of the mixed solution system is reduced, the diameter of the prepared fiber is reduced, and meanwhile, the mild binding force of cinnamyl aldehyde minimally affects the interaction between cellulose acetate molecules.

The invention relates to the technical field of nano materials, and provides a preparation method and application of a friction nano generator with high surface charge density. The invention aims to overcome the defects of low surface charge density, environmental influence, easy aging and the like in high-frequency mechanical energy collection of the existing friction nano-generator, and the application of the friction nano-generator in environmental mechanical energy collection is improved. The main scheme is as follows: 4, the preparation method comprises the following steps: dissolving 4, 4 '-diaminodiphenyl ether in N, N'-dimethylacetamide, adding diphenyl ether dianhydride into the solution to synthesize a polyamide acid solution, carrying out electrospinning and high-temperature treatment on the solution to obtain an imidized nanofiber membrane, treating the surface of the nanofiber membrane through a plasma sputtering instrument, selecting a fluorinated ethylene-propylene copolymer as an electric negative electrode material, and carrying out electrospinning and high-temperature treatment on the surface of the nanofiber membrane. And pasting an electrode and packaging to construct the friction nano generator. The invention is used in the fields of friction power generation, mechanical sensing and the like, and has the advantages of simple process, high preparation speed, high yield, low cost, good robustness, no environmental influence and high output performance.

The present invention relates to the technical field of concrete structure repair, and specifically discloses an anti-freezing spraying material for repairing concrete cracks, its preparation method and application. The spraying material comprises components in the following proportions: 20-85 parts by weight of latex solution, 0.1-3 parts by weight of cross-linking agent, 0.5-4 parts by weight of initiator, 1-15 parts by weight of silicon hydroxylated nanoparticles, 0.5-1.5 parts by weight of dimethylacetamide, 2-10 parts by weight of titanium carbide nanosheets, and 2-30 parts by weight of water. The anti-freezing spraying material of the present invention has the characteristics of good permeability in the cracks of concrete structures and good anti-freezing performance, and is particularly suitable for repairing the cracks of concrete structures by spraying, with convenient and fast construction.

The present application relates to photosensitive polyimide oligomer, preparation method and polyimide photosensitive resin composition prepared by the same, the present application provides the molecular formula of photosensitive polyimide oligomer, which is prepared from 1, 4, 5, 8-naphthalene tetracarboxylic anhydride, N, N-dimethylacetamide, triethylamine, tetramethyl benzene dimethyl diisocyanate, hydroquinone methyl ether, dibutyl tin dilaurate and hydroxyethyl acrylate according to the molar ratio of 2.5:10-15:1.2-1.6:3.0:0.0035-0.0045:0.007-0.01:2-2.5.The good solubility group is introduced into the molecular structure, so that it has good solubility in active diluent, and the polyimide oligomer can be photocured reaction;The device printed by the polyimide photosensitive resin composition prepared by the same has small shrinkage, high precision, and has the excellent performance of photosensitive polyimide oligomer, and has certain toughness and excellent weather resistance.

The invention relates to the field of electrocatalysts, in particular to a simple preparation method of a Ni2P / Fe3P electrocatalyst and application of the Ni2P / Fe3P electrocatalyst in industrial hydrogen production. Nickel nitrate hexahydrate, ferric nitrate nonahydrate, dimethylacetamide, N, N-dimethylacetamide and deionized water are mixed under the stirring condition and subjected to a hydrothermal reaction to obtain a Fe1Ni1-MOF material, then the obtained Fe1Ni1-MOF material is placed in a tubular furnace to be phosphatized, the Ni2P / Fe3P catalyst is obtained, the preparation method is environmentally friendly and simple, the cost is low, the product is pure, and the method is suitable for industrial production. The method has certain stability and activity in an ampere-level industrial current scene, and has a good application prospect.

The present invention relates to a kind of water-resistant honeycomb activated carbon and preparation method thereof, belong to the technical field of activated carbon. A kind of preparation method of water-resistant honeycomb activated carbon comprises the following steps: 1) after heating and firing the coconut shell raw material after cleaning; 2) under nitrogen atmosphere, cyano-modified polyphenylene sulfide, polyetherimide, accelerator and activated carbon powder are mixed uniformly and then heated to react, cooled and washed, and dried; 3) N, N-dimethylacetamide is added to activated carbon intermediate and heated and extracted, solid is filtered and taken, put into anhydrous ethanol and soaked, solid is filtered and taken, after washing; 4) modified activated carbon is placed in anhydrous ethanol, tetrabutyl titanate is added and stirred and mixed, ferric nitrate solution is added by spraying under stirring, ultrasonic treatment is carried out after the addition of materials is completed, solid is filtered and taken, and microwave drying is carried out after centrifugation. The water-resistant honeycomb activated carbon prepared by the present invention has higher stability, water resistance and adsorption.

The invention discloses a preserving fluid for preserving RNA (Ribonucleic Acid) nucleic acid in a biological sample at normal temperature, and belongs to the technical field of biological preserving reagents. The preservation solution comprises the following components in percentage by mass volume: 10-30% of dimethylacetamide, 90-200mM of inorganic salt, 1-10M of cracking agent, 20-100mM of chelating agent, 0.5-5% of reducing agent, 1-5M of stabilizing agent and 30-200mM of buffer salt, wherein the pH (Potential of Hydrogen) of the preservation solution is 6.0-9.0. According to the invention, dimethylacetamide is used as a preservative, so that a biological sample can be preserved at normal temperature for 15 days without degrading RNA nucleic acid. The preserving fluid provided by the invention is very suitable for preserving RNA nucleic acids, especially miRNA, can provide important guarantee for medical detection based on miRNA, and has very important clinical application value.

A process to produce cellulose ester fibers is provided, the process comprising: a. mixing cellulose ester and at least one solvent at a temperature ranging from about 60 ℃ to less than 90 ℃ to produce a cellulose ester dope; wherein the solvent comprises N, N-dimethylformamide, N, N-dimethylacetamide, or dimethyl sulfoxide, or mixtures thereof; and b. spinning the cellulose ester dope through at least one spinneret to produce the cellulose ester fibers; wherein the cellulose ester fibers have improved color over cellulose ester fibers produced from dope mixed outside about 60 ℃ to less than 90 ℃.

The invention discloses an atmospheric fine particulate matter on-line extraction and quantitative concentration device, and relates to the technical field of environmental protection, the atmospheric fine particulate matter on-line extraction and quantitative concentration device comprises an ultrasonic pool, a particulate matter collection bottle fixedly installed at the center in the ultrasonic pool and a collision type PM2.5 filter arranged at the top of the particulate matter collection bottle, a dimethylacetamide solvent is stored in the particulate matter collection bottle, and the collision type PM2.5 filter is arranged at the top of the particulate matter collection bottle. The annular groove is formed in the top of the ultrasonic pool, and an annular piece is inserted into the annular groove in a sliding mode and used for increasing the overall volume of the ultrasonic pool; the two-way lead screw is arranged in the horizontal direction and rotationally arranged in the ultrasonic pool, and two nuts are connected to the two-way lead screw in a threaded and sleeving mode; by starting the motor, the two-way screw rod can rotate, so that the two nuts are close to each other in the arrangement direction of the guide rod, and the two rotating pieces are driven to rotate and push the annular piece to move upwards in the annular groove, so that the overall height of the ultrasonic pool is increased, the volume of the ultrasonic pool is conveniently increased, and the ultrasonic pool is suitable for machining of different specifications.

The invention provides a preparation method of an elastomer material, an anti-leakage artificial blood vessel and a preparation method of the anti-leakage artificial blood vessel, and belongs to the field of biomedical materials. The preparation method comprises the following steps: dissolving polyethylene glycol, hexamethylene hexamethylene diisocyanate and dibutyltin dilaurate in a mixed solution of a first solvent and tetrahydrofuran, carrying out an oil bath reaction at 50-80 DEG C for 3-24 hours to obtain a precursor solution, and then adding a chain extender chitosan oligosaccharide for continuous reaction to obtain a polyurethane elastomer solution. Wherein the first solvent is one of N 'N-dimethylacetamide and DMF (Dimethyl Formamide). Polyethylene glycol which is good in biocompatibility and can be degraded is selected as a soft segment raw material, chitosan oligosaccharide with the molecular weight of 1000-2500 is selected as a chain extender, and the prepared elastomer material has good in-vivo and in-vitro biocompatibility and also has the degradable performance. The prepared polyurethane elastomer solution is sprayed on the artificial blood vessel, and the anti-leakage artificial blood vessel can be prepared. The tensile strength of the prepared anti-leakage artificial blood vessel is larger than or equal to 19 MPa, and the tear resistance can reach 162 kJ m <-2 >.

The invention discloses a catalyst for synthesizing 1, 3-dioxane-2-ketone as well as a preparation method and application of the catalyst. The catalyst is prepared from the following components in percentage by mass: 60wt%-90wt% of a component A, 5wt%-20wt% of a component B and 5wt%-30wt% of a component C, wherein the component A is one or more of N, N-dimethyl formamide, N, N-dimethylacetamide, N, N-diethyl formamide and urea, and the component B is one or more of N, N-dimethyl formamide, N, N-dimethylacetamide, N, N-diethyl formamide and urea; the component B is one or more of lithium carbonate, sodium carbonate, potassium carbonate, cesium carbonate, calcium carbonate and magnesium carbonate; and the component C is 1-butyl-3-methylimidazolium tetrafluoroborate and / or 1-butyl-3-methylimidazolium hexafluorophosphate, and the component C is 1-butyl-3-methylimidazolium hexafluorophosphate. According to the present invention, the components of the catalyst have the mutual synergistic promotion effect, the reaction substrate can be adsorbed and activated, the reaction condition is mild, the product yield is high, the catalyst can be recovered and regenerated, and the environmental pollution is low.

The invention relates to the technical field of production of flurala drops, in particular to a flurala drop preparation method based on online monitoring. The preparation method comprises the following preparation processes: sequentially adding weighed dimethylacetamide and acetone into a liquid preparation tank, adding fluralana and tetrahydrofuran polyglycol ether into the liquid preparation tank, stirring until the materials are uniformly mixed, monitoring raw material data, production data and product data by using a monitoring and collecting system in the preparation process, and recording and storing the raw material data, production data and product data through a monitoring and recording system. Data collected by the monitoring and collecting system is used as a reference, production is controlled and commanded through the monitoring and controlling system, and the monitoring and recording system records and stores the data and sends the data to the monitoring and analyzing system for statistical analysis and machine learning training. Key links such as raw material parameters, environmental process parameters and intermediate product and finished product quality data are monitored online in real time through the monitoring and collecting system, the production dynamic state is comprehensively mastered, and it is guaranteed that all procedures are strictly executed according to the process requirements.

The invention discloses a membrane separation material for purifying a sucralose-6-acetate alcoholysis product. The technology comprises three main parts, namely MOF (Metal Organic Framework) synthesis, membrane preparation and membrane dialysis separation. The method comprises the following steps: firstly, taking gamma-cyclodextrin and sodium hydroxide as raw materials, carrying out morphology adjustment by using hexadecyl trimethyl ammonium bromide, and synthesizing Na-gamma-CD-MOF by using a solvent method; then mixing the MOF material with N, N-dimethylacetamide and polyvinylidene fluoride in proportion to prepare a membrane casting solution, and preparing the membrane casting solution into a composite membrane material by using a phase inversion method; finally, the membrane is placed in a liquid phase dialysis device, dialysis separation is conducted on all components in the sucralose-6-acetate alcoholysis product, and efficient separation of impurities and efficient purification of the main product sucralose are achieved. The advantages of the membrane separation technology are fully utilized, conditions are mild, the device is simple, operation is convenient, and the method has good application prospects.

The invention relates to the technical field of organic synthesis, in particular to a preparation method of crude poly (p-phenylene terephthamide). According to the method, phase-to-phase switching between non-aqueous suspension and ionic liquid homogeneous phase is adopted, and AB type end group balance, alternating end sealing and interface confinement branching are combined to realize end group accurate control and molecular weight distribution convergence. The method comprises the following steps: emulsifying an N-methyl pyrrolidone / calcium chloride solution in paraffin oil; carrying out polycondensation with p-phenylenediamine and paraphthaloyl chloride at a low temperature, and adding p-aminobenzoyl chloride to carry out dynamic balance on an end group; after layering, transferring into 1-butyl-3-methylimidazole chloride / N, N-dimethylacetamide for continuous polycondensation; cooling and re-emulsifying, and alternately adding benzoyl chloride and p-toluyl chloride for end sealing; trimesoyl chloride is added to a phase interface to realize limited branching; and carrying out ionic liquid homogenization, amine termination and alcohol / water sedimentation washing to obtain the product. The method effectively relieves end group drift, inhibits high molecular weight tailing and improves the filtering performance, and is suitable for preparation of high-reliability aramid fibers.