196 results about "Tetramethylethylenediamine" patented technology

The invention discloses a CO2 trapping absorbent which comprises 20%-50% of proton type ionic liquid, 20%-50% of a phase conversion driving agent and 20%-40% of water, and the phase inversion driving agent is one or a mixture of more of N, N-dimethyl formamide, N-methyl pyrrolidone, pentamethyldiethylenetriamine, tetramethylethylenediamine, tetramethylethylenediamine, tetramethylenediamine, tetramethylethylenediamine and dimethyl piperazine, and the phase inversion driving agent is one or a mixture of more of N, N-dimethyl formamide, N-methyl pyrrolidone, pentamethyldiethylenetriamine, tetramethylethylenediamine, tetramethylethylenediamine and dimethyl piperazine. The absorbent disclosed by the invention has the outstanding advantages of low viscosity, high absorption rate, high regeneration efficiency, high circulation capacity and low regeneration energy consumption, and has a good application prospect.

The invention discloses a preparation method of atmospheric water collection porous gel, and belongs to the technical field of environmental ecological restoration, the method comprises the following steps: S1, dissolving a monomer, a foam stabilizer and a foaming aid in an acidic solution, and stirring to form a solution A; s2, mixing N, N '-methylene bisacrylamide, tetramethylethylenediamine and an initiator with the solution A to form a solution B; s3, mixing and stirring a foaming agent and the solution B, and standing for reaction to form a substrate C; s4, drying the matrix C, and immersing the matrix C into the solution D for reaction to form a precursor E; and S5, drying the precursor E to obtain the atmospheric water collection porous gel material. The problems that in the prior art, the preparation process is complex, and the foaming process is uncontrollable are solved.

The invention discloses preparation and application of a block cationic copolymer / quaternary ammonium salt chitosan-based composite hydrogel. The preparation method comprises the following steps: reacting a sodium alginate solution with a NaIO4 solution at room temperature in a dark place to obtain an oxidized sodium alginate solution; adding ethylene glycol into the oxidized sodium alginate solution, reacting, concentrating, dialyzing and drying to obtain oxidized sodium alginate; the preparation method comprises the following steps: mixing acrylamide, 1-butyl-3-vinyl imidazole ammonium bromide, 3-acrylamide phenylboronic acid and quaternary ammonium salt chitosan, dissolving in water, adding ammonium persulfate and N, N-methylene bisacrylamide, heating for reaction, and cooling to obtain a cooling liquid; adding the oxidized sodium alginate solution into the cooling liquid, continuously adding polymerized N, N, N ', N'-tetramethylethylenediamine, reacting and curing to obtain composite hydrogel; and soaking the composite hydrogel in a glycerin / water mixed solution to obtain the composite hydrogel. When the composite hydrogel is used as a wound dressing, the composite hydrogel has the characteristics of good antibacterial activity, high sterilization efficiency, good anti-freezing and anti-drying performance and difficulty in generating drug resistance.

The invention discloses photocuring conductive hydrogel as well as a preparation method and application thereof. According to the invention, methacryloylethyl sulfobetaine (SBMA), acrylic acid (AA) and hydroxyethyl methylacrylate (HEMA) are used as comonomers, deionized water is used as a solvent, N, N '-methylenebisacrylamide (MBAA) is used as a cross-linking agent, ammonium persulfate (APS) is used as an initiator, tetramethylethylenediamine (TEMED) is used as an accelerator, and 2-hydroxy-4'-(2-hydroxyethoxy)-2-methyl propiophenone (Irgacure2959) is used as a photoinitiator; the conductivity is improved by adding an ionic compound potassium chloride (KCl), and the photocuring conductive hydrogel is prepared in a free radical polymerization manner by adopting an LED-UV curing box. The conductive hydrogel disclosed by the invention has the characteristics of good adhesion property, conductivity, mechanical property and the like, and has wide application in the fields of wearable strain sensors and other flexible electronics.

The invention relates to a spongy gel phase change cold storage agent for fruit and vegetable preservation and a preparation method thereof. The preparation method comprises the following steps: 1) sequentially adding sodium alginate powder, an N, N '-methylene bisacrylamide aqueous solution, tetramethylethylenediamine and an ammonium persulfate aqueous solution into an acrylamide aqueous solution; (2) transferring the mixed solution into a polytetrafluoroethylene container, quickly putting the polytetrafluoroethylene container into a vacuum dryer filled with allochroic silicagel, vacuumizing by adopting a circulating water vacuum pump, and sealing for overnight cross-linking to prepare spongy gel; and 3) soaking the spongy gel in a potassium chloride solution to prepare the spongy gel phase change cold storage agent. The spongy gel phase change cold storage agent prepared by the method disclosed by the invention has high phase change latent heat and high flexibility; the device can be freely cut to fit the logistics space, and the problem that the internal environment temperature of the logistics space is not uniform due to local cooling is avoided; the potassium chloride solution is used as an additive for adjusting the phase change temperature of the gel cold storage agent, and the appropriate phase change temperature can be adjusted according to different fruits and vegetables.

The invention provides a gel composite adsorbent with a foaming structure as well as a preparation method and application thereof, and the preparation method comprises the following steps: S1, dissolving acrylamide powder in deionized water, and stirring to obtain a solution A; s2, dissolving sodium alginate in the solution A for thickening to obtain a solution B; s3, transferring the solution B into an ice-water bath; s4, adding N, N-methylene bisacrylamide into the solution B, stirring until the N, N-methylene bisacrylamide is completely dissolved, then adding N, N, N ', N'-tetramethylethylenediamine, and stirring until the N, N, N ', N'-tetramethylethylenediamine is uniform to obtain a solution C; s5, adding ammonium persulfate into the solution C, and stirring until the ammonium persulfate is completely dissolved to obtain a solution D; s6, the solution D is poured into a mold and then vacuumized to form gel, and a hydrogel sample is obtained after gel forming; s7, drying the hydrogel sample, and then soaking the dried hydrogel sample in a salt solution to obtain a soaked gel material; and S8, drying the soaked gel material to obtain the finished product composite adsorbent.

The invention discloses a synthesis method of an aryl bidentate phosphine compound, which comprises the following steps of: (1) reacting benzene or alkylbenzene with benzyl chloride or 4-alkyl benzyl chloride at 0-100 DEG C for 0.5-5 hours in the absence of oxygen and under the condition of a lewis acid catalyst to prepare a first intermediate; (2) dropwise adding an alkyl lithium reagent into tetramethylethylenediamine at the temperature of-30 to 40 DEG C under the conditions of no water, no oxygen and a solvent, stirring for 1 to 3 hours, dropwise adding the first intermediate into the mixed solution at normal temperature, and reacting for 4 to 20 hours at the temperature of-20 to 40 DEG C to prepare a second intermediate; and (3) under anhydrous and anaerobic conditions, adding diphenyl phosphine chloride into the second intermediate obtained in the step (2), and reacting at-20 to 80 DEG C for 5-60 hours to obtain the aryl bidentate phosphine compound. The synthesis method disclosed by the invention is simple in process, mild in condition and high in product yield, and has a relatively good industrial prospect.

The invention discloses a photonic crystal hydrogel-based thermochromic intelligent window material as well as a preparation method and application thereof. The photonic crystal hydrogel-based thermochromic intelligent window material is obtained by filling a three-dimensional photonic crystal structure with a temperature-sensitive hydrogel prepolymerization solution and then curing the three-dimensional photonic crystal structure; the preparation method comprises the following steps: adding a temperature-sensitive monomer, modified cellulose and a cross-linking agent into deionized water, carrying out ultrasonic dispersion, stirring under an ice bath condition until the materials are completely dissolved, adding an initiator, stirring until the materials are dissolved, adding N, N, N ', N'-tetramethylethylenediamine, and uniformly stirring to obtain the temperature-sensitive hydrogel prepolymer. The photonic crystal hydrogel-based thermochromic intelligent window material prepared by the invention can regulate and control the window transmittance in real time according to the environment temperature, and has a sensitive thermochromic effect and excellent infrared shielding performance.

The invention belongs to the technical field of textile dyeing and finishing, and particularly relates to a long-acting hydrophilic, soft, fluffy and washable silicone oil composition as well as a preparation method and application thereof. The silicone oil composition is prepared from the following raw materials in parts by mass: 20 parts of modified silicone oil, 0.5 to 2.5 parts of anionic surfactant, 0.5 to 2 parts of nonionic surfactant, 0.1 to 1 part of polyhexamethylene biguanide hydrochloride, 0.2 to 0.5 part of glacial acetic acid and 76 to 79 parts of water, the modified silicone oil is prepared from the following raw materials: octamethylcyclotetrasiloxane, tetramethylethylenediamine, secondary aminated polyether amine, allyl epoxy polyether, polyether amine, allyl glycidyl ether, isopropanol, diethylene glycol butyl ether, an end-capping reagent and a catalyst. The silicone oil composition provided by the invention can endow a fabric with a long-acting hydrophilic effect, excellent hand feeling, low yellowing and washability; and the dye has excellent stability, is safe and stable to use, and does not influence the colored light of the dyed fabric.

The invention discloses a self-adaptive hydrogel coupling agent as well as a preparation method and application thereof, belongs to the field of medical instruments, and particularly relates to a preparation method of the self-adaptive hydrogel coupling agent. The preparation method comprises the following steps: dissolving a main monomer, a functional monomer, a molecular weight regulator and a reinforcing filler in sterilized deionized water under dark and sterile conditions, carrying out a free radical polymerization reaction under the action of a persulfate solution and tetramethylethylenediamine, and carrying out dialysis and sterilization treatment to obtain the self-adaptive hydrogel coupling agent. The self-adaptive hydrogel coupling agent prepared by the invention eliminates tissue deformation caused by probe pressurization, significantly improves the accuracy of measurement of the actual distance of a target by ultrasound in an operation, and meanwhile, the self-adaptive hydrogel coupling agent is good in biocompatibility, can be sterile, is convenient to operate, and is suitable for open or endoscopic surgical wounds.

The invention relates to an intelligent composite material diaphragm as well as a preparation method and application thereof. The intelligent composite material diaphragm comprises a shape memory polymer foam skeleton and a gel electrolyte filled in the shape memory polymer foam skeleton, the shape memory polymer foam skeleton is prepared from the following raw materials: epoxy resin and a D-230 curing agent; the gel electrolyte is prepared from the following raw materials: N-isopropylacrylamide, acrylamide, N, N '-methylene bisacrylamide, ammonium persulfate, tetramethylethylenediamine and a lithium salt solution. The intelligent composite material diaphragm can perform real-time response according to the temperature change in the working process of the battery, adjust the ionic conductivity to control the output power of the battery, provide over-temperature protection, have an automatic thermal protection function, further have a function of inhibiting the growth of lithium dendrites, can prolong the service life of the battery, and is suitable for popularization and application. And the battery is especially suitable for battery application scenes with high energy density and high safety requirements.

The invention provides a preparation method of an insecticide synergistic responsive release delivery system, and belongs to the technical field of insecticides. Chlorantraniliprole insecticide is dissolved in an acetone solvent containing Tween 80 to form a drug-carrier complex; then polymerizing the N-isopropylacrylamide temperature-sensitive monomer under the action of an ammonium persulfate and tetramethylethylenediamine initiation system to form a temperature-responsive hydrogel matrix; four key parameters including the optimal molar ratio, the optimal embedding temperature, the optimal embedding time and the optimal phase change temperature control precision of an amido hydrophilic group and an isopropyl hydrophobic group are calculated by applying a double-layer game model, and a drug-carrier complex is embedded into a hydrogel matrix through a physical embedding effect to construct a three-layer nested delivery structure; the technical problem that the pesticide effect utilization rate is low due to the fact that the pesticide lacks an accurate temperature-responsive release control mechanism in environmental application is solved.

The invention relates to the technical field of pharmaceutical preparations, and discloses a mild photo-thermal microneedle patch and a preparation method and application thereof, and the mild photo-thermal microneedle patch comprises a substrate and needle tips arranged on the substrate in an array; the substrate is prepared from the following raw materials in parts by weight: 400 to 500 parts of N-isopropylacrylamide, 30.5 to 40.5 parts of acrylamide, 4 to 5 parts of polydopamine nanoparticles, 10 to 30 parts of N, N-methylene bisacrylamide, 100 to 200 parts of sodium alginate, 6.2 to 9.3 parts of tetramethylethylenediamine and 8 to 12 parts of potassium persulfate; the needle tip is prepared from the following raw materials in parts by weight: 0.1 to 0.5 part of methacrylated gelatin, 0.2 to 0.6 part of deferoxamine mesylate, 0.8 to 1.2 parts of a photoinitiator and 33.6 to 56 parts of polyethylene glycol diacrylate. The mild photo-thermal microneedle patch can realize photo-thermal sterilization under near-infrared irradiation, and also can promote skin repair and regeneration.

The invention relates to the technical field of gel material preparation, in particular to a bio-based gel material for dangerous chemical leakage disposal and a preparation method thereof.The preparation method comprises the steps that gelatin and deionized water are added into a reaction container, a gelatin solution is obtained under the preset dissolution condition, alkaline protease is added into the gelatin solution for an enzymolysis reaction, and a gelatin solution is obtained; a modified gelatin solution is obtained; the preparation method comprises the following steps: adding a phytic acid-chitosan compound and magnesium-aluminum layered double hydroxide into dispersion equipment, and obtaining a composite inorganic matter dispersion liquid under a preset dispersion condition; adding the modified gelatin solution, the composite inorganic substance dispersion liquid, polyethylene glycol and phase change microcapsules into a mixing reactor, and obtaining a premixed solution under a preset mixing condition; sequentially adding an initiator, a cross-linking agent and tetramethylethylenediamine into the premixed liquid, and performing cross-linking reaction under preset cross-linking conditions to obtain a bio-based gel initial product. The plugging efficiency of the bio-based gel material on dangerous chemical leakage is improved.

The invention discloses a method for preparing high-entropy boride ultrahigh-temperature ceramic powder by a liquid phase method. The green, low-cost and controllable high-entropy boride superhigh-temperature ceramic powder is prepared by taking a transition metal oxide as a metal source, boric acid as a boron source and sorbitol as a carbon source through a liquid phase method in combination with a boron thermal / carbon thermal reduction reaction. According to the preparation method disclosed by the invention, the ammonium sulfate, the tetramethylethylenediamine, the acrylamide and the N, N '-methylene bisacrylamide are used for carrying out gelation treatment to obtain the pure-phase high-entropy boride ultrahigh-temperature ceramic powder, so that a feasible strategy is provided for preparing the high-entropy boride ultrahigh-temperature ceramic powder which is efficient, environment-friendly and economical.

The invention relates to the technical field of fertilizers, and discloses a water-retaining slow-release fertilizer and a preparation method thereof. The nitrogen fertilizer is prepared from the following raw materials in parts by weight: 30 to 40 parts of nitrogen fertilizer, 15 to 20 parts of chitosan, 1 to 2 parts of urease inhibitor, 3 to 5 parts of maleic anhydride grafted compatilizer, 100 parts of acetic acid solution, 20 to 25 parts of acrylamide, 1 to 2 parts of 2-mercaptobenzoic acid, 0.4 to 0.6 part of ammonium persulfate, 0.4 to 0.6 part of tetramethylethylenediamine, 4 to 6 parts of calcium carbonate powder, 10 to 15 parts of talcum powder and 0.3 to 0.5 part of nitrification inhibitor. According to the invention, chitosan and acrylamide are copolymerized and prepared into the hydrogel, and the three-dimensional network structure contains a large amount of hydroxyl groups, so that the water absorption and holding capacity of the polymer can be greatly improved. The nitrogen fertilizer is wrapped by a three-dimensional network structure of the polymer, is gradually hydrolyzed when encountering water, and cooperates with the urease inhibitor grafted on the polymer and a coating film formed on the surface, so that an efficient slow-release and controlled-release effect is achieved.

The invention discloses preparation and application of natural biomass water retention gel for water collection and retention of arid soil, and the preparation method comprises the following steps: dissolving sodium alginate and carboxymethyl cellulose in deionized water, and then adding lithium chloride, an N-isopropylacrylamide monomer and N, N '-dimethyl diacrylamide to obtain a mixture; foaming the mixture with Ar gas, then adding N, N, N ', N'-tetramethylethylenediamine, a polymerization accelerator and ammonium peroxide as initiators, and polymerizing to obtain mixed gel; dropwise adding the mixed gel into a calcium chloride aqueous solution through a microfluidic method to obtain hydrogel beads, washing and drying to obtain the natural biomass water-retaining gel. The natural biomass water retention gel contains a three-dimensional porous structure, enhances adsorption-desorption kinetics, and effectively inhibits aggregation of hygroscopic salt-LiCl particles in a hydration process, so that good water absorption performance and cycling stability are realized, water vapor can be extracted from arid climate, and water can be effectively captured from atmosphere.

The invention relates to the technical field of polycarbonate, and discloses a preparation process of a halogen-free flame-retardant high-strength polycarbonate composite material, wherein a DOPO dicarbonate ethyl chloride intermediate and N,N,N',N'-tetramethylethylenediamine are reacted to obtain a cationic DOPO carbonate-based polymer flame retardant. Then, the carbon nanotubes are modified with sodium triazine benzenesulfonate to blend and modify the polycarbonate. The polymer flame retardant contains the same carbonate structural unit as the polycarbonate, and the two have good structural similarity and compatibility, and will not affect the mechanical properties of the polycarbonate. At the same time, the interface interaction and compatibility between the carbon nanotubes and the polycarbonate are improved, and the tensile properties and impact strength of the polycarbonate are improved. The polymer flame retardant contains a DOPO flame retardant group, and the surface of the carbon nanotube contains a triazine functional group and a sulfonate group, which significantly improves the flame retardant properties of the polycarbonate.

The invention relates to the technical field of glass, in particular to heat insulation type fireproof glass and a manufacturing method thereof.The heat insulation type fireproof glass comprises a fire-facing glass layer and a fire-backing glass layer, and the space between the fire-facing glass layer and the fire-backing glass layer is filled with a polyacrylamide gel layer; the polyacrylamide gel layer is prepared from the following raw materials: acrylamide, octa-amino POSS (Polyhedral Oligomeric Silsesquioxane), polydopamine modified tetrapod-like zinc oxide whiskers, a composite flame retardant, a cross-linking agent, tetramethylethylenediamine, an initiator and deionized water; the mass ratio of the acrylamide to the octa-amino POSS to the polydopamine modified tetrapod-like zinc oxide whisker is (30-38): (2.5-4): (1.5-2.2); the heat insulation type fireproof glass has excellent fireproof performance, heat insulation performance and aging resistance.

The invention discloses SDS-PAGE polyacrylamide gel prepared by a one-step method, the SDS-PAGE polyacrylamide gel comprises a separation gel and a concentration gel, the separation gel comprises the following components: a Tris-HCl buffer solution, acrylamide, N, N '-methylene bisacrylamide, a trihalide compound, lauryl sodium sulfate, an ammonium persulfate solution, a glycerin aqueous solution, tetramethylethylenediamine and water; the concentrated gel is prepared from the following components: a Tris-HCl buffer solution, acrylamide, N, N '-methylene bisacrylamide, lauryl sodium sulfate, an ammonium persulfate solution, tetramethylethylenediamine and ultrapure water. The polyacrylamide gel provided by the invention can be used for preparing gel by a one-step method, so that a sample loading hole is clearer and more visible, and a clear protein band can be presented by irradiating for 60-90 seconds under 300 nm ultraviolet after electrophoresis.

The invention relates to the technical field of high polymer chemical polymerization, in particular to sodium alginate-based polyacrylamide hydrogel and a preparation method thereof. The sodium alginate-based polyacrylamide hydrogel is prepared from the following components in parts by mass: 10 to 20 parts of acrylamide, 10 to 15 parts of sodium alginate, 3 to 7 parts of modified montmorillonite, 1 to 3 parts of nano titanium dioxide, 0.3 to 0.9 part of anhydrous calcium chloride, 0.1 to 0.5 part of a cross-linking agent, a photoinitiator and tetramethylethylenediamine. The invention provides a sodium alginate-based polyacrylamide hydrogel and a preparation method thereof, and aims to solve the problems of poor mechanical properties and poor heat resistance of sodium alginate-acrylamide composite gel in related technologies.

The invention relates to the technical field of oilfield chemistry, in particular to a clay stabilizer containing dihydroxyl quaternary ammonium salt and a preparation method thereof, and the preparation method of the clay stabilizer containing dihydroxyl quaternary ammonium salt comprises the following steps: mixing required amounts of tetramethylethylenediamine, 3-chloro-2-hydroxypropyl trimethyl ammonium chloride and a hydrogen bond donor for reaction to obtain the clay stabilizer containing dihydroxyl quaternary ammonium salt. And after the reaction is ended, obtaining the clay stabilizer containing the dihydroxyl quaternary ammonium salt. The clay stabilizer containing dihydroxyl quaternary ammonium salt is high in charge density and remarkable in clay expansion prevention effect; the fabric has the characteristic of multi-point adsorption and is high in washing resistance; the polymer is composed of small molecular weight compounds and can be used for transformation of low-permeability and ultra-low-permeability reservoirs. And meanwhile, the fracturing fluid has good compatibility with the fracturing fluid, the influence on the viscosity of the fracturing fluid is small, and the sand-carrying performance of the fracturing fluid can be guaranteed while reservoir protection is realized. The preparation method of the clay stabilizer containing the dihydroxyl quaternary ammonium salt is simple in process, easy to control and implement and suitable for industrial large-scale production.

The invention belongs to the technical field of underground engineering grouting materials, and discloses an anti-dispersion solid waste grouting filling material and a preparation method and application thereof. The slurry A is prepared from the following components in parts by mass: 400 to 1000 parts of fly ash, 500 to 1000 parts of blast furnace slag, 100 to 500 parts of Portland cement, 250 to 1200 parts of water, 5 to 50 parts of sodium hydroxide and 10 to 50 parts of PolyFure-I; the polyFure-I comprises acrylamide and N, N, N ', N'-tetramethylethylenediamine, and the polyFure-I comprises acrylamide and N, N, N ', N'-tetramethylethylenediamine; the slurry B is prepared from the following components in parts by mass: water glass and PolyFure-II; the PolyFure-II is prepared from water glass, an ammonium persulfate solution, xanthan gum and carboxymethyl cellulose. The flowing water dispersion resistance of the grouting material is effectively improved, the blocking effect of flowing water is enhanced, and the problem of insufficient blocking of a traditional grouting material is solved.

The invention provides a preparation method of a cyano chlorosilane compound, and the preparation method of the cyano chlorosilane compound comprises the following steps: reacting methyl dichlorosilane with a cyano-containing olefin compound under the action of a catalyst to obtain the cyano chlorosilane compound, the catalyst comprises a combination of cuprous salt, organic alkali and tetramethylethylenediamine. According to the method, methyl dichlorosilane and cyano-containing olefin are used as raw materials to react, and the cyano chlorosilane compound is prepared under the action of a specific catalyst; the preparation method is simple in reaction operation, the yield is 76% or above, the purity is 99.1% or above, and the preparation method is suitable for industrial production.

The invention discloses double-crosslinking personalized hydrogel for promoting wound healing and a preparation process thereof, and relates to the technical field of biomedical materials. The hydrogel comprises sodium alginate, modified chitosan, calcium carbonate, glucolactone, acrylamide, methylene diacrylamide, ammonium persulfate and tetramethylethylenediamine, and the hydrogel can also carry drugs in the preparation process, including but not limited to drugs with the functions of diminishing inflammation, resisting bacteria, stopping bleeding and the like. The hydrogel is prepared in a double-crosslinking mode of physical crosslinking and chemical crosslinking. The hydrogel provided by the invention has the advantages of high biocompatibility, adjustable viscosity, easy replacement, adjustable water absorbability and temperature responsiveness, has a loose porous structure, has better water content, cell proliferation and migration performance, swelling performance, drug sustained release performance and the like, can effectively promote wound healing, and has a good application prospect. The method has potential application prospects in skin wound treatment and repair.

The present invention relates to a medical hydrogel, and in particular to a hydrogel, a preparation method therefor and the use thereof. The preparation method comprises the steps of: completely dissolving polyvinyl alcohol in deionized water to obtain a component A in a clear state; dissolving acrylamide in deionized water, then adding N,N-methylene bisacrylamide and ammonium persulfate, and mixing same until uniform to obtain a component B; and mixing the component A and the component B at a volume ratio of 1:1 and stirring same until the mixture is completely clear and transparent, then adding Ag-ZnO nanoparticles, and finally dropwise adding a tetramethylethylenediamine solution to obtain a hydrogel prepolymer, and curing same to obtain the hydrogel. The hydrogel obtained in the present invention can be applied to an organ model for surgical training, so that the prepared organ model can more accurately simulate the properties of a biological soft tissue to make surgical training more realistic, has a better performance in terms of inhibiting bacteria, anti-fatigue, electric conduction, stretching, compression and the like, and can also be subjected to operations such as electrocoagulation and hemostasis, endoscopy, suturing and cutting.

The present invention discloses a preparation method of chrome-free tanned upper leather, comprising the following steps: Step 1: Re-wetting Add the prepared aqueous solution of sodium chloride and sodium bicarbonate into a drum machine, and then put in the raw hide, and rotate for 10 - 30 min; Step 2: Water washing Immerse the re-wetted raw hide in pure water and wash for 10 - 30 min; Step 3: Tanning Add water, a catalyst, and a modified tanning agent into the drum machine, and run the drum machine for tanning for 200 - 360 min; Step 4: Alkali raising Add sodium bicarbonate into the drum machine, adjust the pH to 8.0, raise the temperature to 35 °C, rotate for 4 h, stand for 5 - 20 h, and dry to obtain the upper leather; The modified tanning agent is formed by the reaction of starch, trimethylolethane triglycidyl ether, tetramethylethylenediamine, N-(2-hydroxyethyl)guanidine, and epoxypropionic acid. The purpose of the present invention is to provide a preparation method of chrome-free tanned upper leather.

This invention relates to a method for preparing a broadband absorption hydrogel. The method comprises the following steps: S1, mixing solvent A (N,N-dimethylformamide or acetonitrile) with deionized water to obtain a mixed solvent; S2, adding polyethylene glycol methyl ether acrylate-480 and acryloylmorpholine to the solvent in S1 and dissolving them to obtain a mixed solution; S3, removing dissolved oxygen from the mixed solution in S2, sealing the container, and stirring under ice bath conditions; S4, adding potassium persulfate and N,N,N',N'-tetramethylethylenediamine to the mixed solution after stirring in S3, and sealing the container again; S5, completing the polymerization reaction in the container at 60 °C to obtain the hydrogel. Compared with the prior art, the hydrogel material provided by this invention has improved reflection loss intensity and effective absorption bandwidth performance, thus providing a new perspective for developing highly flexible and efficient electromagnetic wave absorbers.

The preparation method comprises the following steps: under the protection of nitrogen, mixing N-isopropylacrylamide and potassium persulfate, adding mesoporous silica and deionized water, carrying out ultrasonic treatment for 10-60 minutes, uniformly mixing, carrying out polymerization reaction for 0.5-2 hours under the constant temperature condition of 20-30 DEG C, adding tetramethylethylenediamine, carrying out ultrasonic treatment for 20-30 minutes, and carrying out ultrasonic treatment for 20-30 minutes to obtain the degradable PNIPAM / MSN hydrogel. Carrying out constant-temperature polymerization for 6 to 24 hours under the condition that the temperature is 20 to 30 DEG C, so as to obtain the degradable PNIPAM / MSN hydrogel. By adjusting the polymerization time, the natural degradation time of the sample can be regulated and controlled, the process is simple, the stability is good, the translation entropy of water molecules and ions is maximized, the LCST point is effectively controlled, and the method can be widely applied to a drug delivery system.

The invention relates to polyvinyl alcohol polynitrogen isoacrylamide cellulose hydrogel with an anisotropic structure as well as a preparation method and application of the polyvinyl alcohol polynitrogen isoacrylamide cellulose hydrogel, and belongs to the technical field of water catching materials. The preparation method of the hydrogel comprises the following steps: S1, adding polyvinyl alcohol, glutaraldehyde and lithium chloride into deionized water to obtain a mixed solution A; s2, adding the cellulose nanocrystal powder into deionized water to obtain a cellulose nanocrystal dispersion liquid; s3, adding N-isoacrylamide and N, N-methylene bisacrylamide into deionized water, so as to obtain a mixed solution B; s4, adding the mixed solution A and the cellulose nanocrystal dispersion solution into the mixed solution B, and reacting to obtain a mixed solution C; s5, ammonium persulfate, hydrochloric acid and tetramethylethylenediamine are added into the mixed solution C, freezing, low-temperature crosslinking and unfreezing are conducted, and then freezing-unfreezing circulation crosslinking is conducted; and finally, taking out, unfreezing and dialyzing. The hydrogel provided by the invention has a highly anisotropic structure and regular vertical pore channels.