155results about How to "The synthesis process is easy to control" patented technology

The invention relates to a preparation method of a star polycarboxylic acid high-performance water reducing agent. Polybasic alcohol and (methyl) acrylic acid used as main raw materials for esterification are esterified and polymerized to prepare the star polycarboxylic acid high-performance water reducing agent material: the (methyl) acrylic acid and polybasic alcohol used as reactants are esterified under the action of a catalyst to firstly prepare a star polymerizable active terminal, and free-radical polymerization reaction is carried out with unsaturated polyethenoxy ether, molecular weight regulator and unsaturated carboxylic acid monomer under the action of an initiator to prepare the star polycarboxylic acid high-performance water reducing agent. The invention is easy to control, and has the advantages of high polymerization degree, low cost and no pollution; the esterification reaction is carried out form an active core, and the free-radical polymerization is carried out to generate the chain arm, thereby implementing the polycarboxylic acid high-performance water reducing agent in a star molecular structure; and under the condition of common doping amount and low doping amount, the star polycarboxylic acid high-performance water reducing agent has better cement paste flowability and holding capacity than the traditional linear and comb polycarboxylic acid water reducing agents, and has favorable cement adaptability and concrete application performance.

The invention discloses a self-healing polymer material and a preparation method thereof. The self-healing polymer material comprises at least one polyurethane polymer prepared by random copolymerization reaction of a low polymer dihydric alcohol, a chain extender and a first diisocyanate, wherein the chain extender comprises at least one multiple hydrogen bond chain extender. The invention further provides a preparation method of the self-healing polymer material. The method comprises the following steps: preparing a ureido pyrimidone type end-capping reagent or chain extender, and preparing the low-temperature rapid self-healing polymer material containing quadruple hydrogen bond groups on side chains and end groups by utilizing the random copolymerization reaction of the low polymer diglycol, the chain extender and the first diisocyanate. Compared with the traditional self-healing material, the self-healing material disclosed by the invention can realize repeated self-healing at the same position at a low temperature without adding a repair agent to the damaged part, and the self-healing polymer material is high in healing ability, excellent in mechanical property, excellent in material film-forming property and transparency, simple in process and low in cost.

The invention discloses a synthesis method of a polycarboxylic acid high-performance water reducing agent of a star-like structure, belonging to the field of a water reducing agent. According to the synthesis method, polybasic alcohol, (methyl) acrylic acid, a polyethylene glycol compound and the like are used as esterification raw materials, and the polycarboxylic acid high-performance water reducing agent of the star-like structure is prepared through a sequential esterification and polymerization method, i.e., the (methyl) acrylic acid and the polybasic alcohol are used as reactants, a star-like polymerizable active end is prepared through esterification reaction under the action of a catalyst, and then the polycarboxylic acid high-performance water reducing agent is prepared from the star-like polymerizable active end and esterification macromolecule, a molecular weight regulator and an unsaturated carboxylic acid monomer under the action of an initiator through free radical polymerization reaction. The synthesis method has the advantages of simplicity, easiness in control, high polymerization degree, low cost, no pollution, capability of realizing the polycarboxylic acid high-performance water reducing agent of the star-like structure connected with a plurality of polycarboxylic acid molecules, and more superior cement paste fluidity and holding capacity, good cement adaptability and concrete application performance compared with the conventional linear and comb-shaped polycarboxylic acid water reducing agent in the case of normal and low added amount.

The invention discloses a preparation method of a polyester type pure solid polycarboxylic acid high-performance water reducing agent, belonging to the field of water reducing agents. According to the invention, by taking a (methyl) acrylic acid monomer and a polyethylene glycol compound as reactants, a polymerizable macromonomer is prepared through esterification reaction under the effect of a catalyst, and the polymerizable macromonomer conducts a free radical bulk polymerization reaction with an unsaturated carboxylic acid monomer and a chain transfer agent under the effect of an initiator in an environment without any solvent to obtain the polyester type pure solid polycarboxylic acid high-performance water reducing agent. The method disclosed by the invention has strong process controllability, high degree of polymerization and low cost and prevents environmental pollution; a completely anhydrous polyester type pure solid polycarboxylic acid high-performance water reducing agent is prepared through esterification reaction and bulk polymerization, which has neat cement paste liquidity and holding ability, cement adaptability and concrete application performance similar to a traditional solution method; meanwhile, since the polymer product is an anhydrous pure solid, a solution with any concentration can be prepared according to actual needs; and without the after-treatment processes such as heating and drying, solvent separation and the like, the transportation is more convenient, and good market competitiveness and application prospects are realized.

The invention relates to a solvent-free method for preparing non-ionic water-borne polyurethane. The method comprises the following steps: firstly, synthesizing a Y-shaped side chain nonionic hydrophilic chain extender containing two terminal hydroxyl groups; secondly, reacting poly(dihydric alcohol) with isocyanate, and adding the Y-shaped side chain nonionic hydrophilic chain extender for chain extending to generate a side chain prepolymer with a -NCO terminal-group; thirdly, adding one or mixture of two of small-molecular dihydric alcohol and oligomer polyol, uniformly stirring, and immediately adding a deionized water solution to disperse at high speed; and finally heating to react to obtain a stable solvent-free nonionic waterborne oligomer emulsion. Compared with the prior art, the method has the advantage that the stable solvent-free nonionic waterborne oligomer emulsion is prepared under conditions of no additional emulsifier and little co-stabilizer.

The invention provides a preparation method of InP / GaP / ZnS nucleocapsid quantum dots. The preparation method comprises the following steps of dissolving an indium precursor, a gallium precursor and a zinc precursor in organic solvent, and obtaining a mixed precursor solution of indium, gallium and zinc; adding a phosphorus precursor to the mixed precursor solution of indium, gallium and zinc, and obtaining an InP / GaP: Zn quantum dot nuclear solution after a reaction; adding a shell material, which is a mixed solution of a zinc salt solution and thiol, into the InP / GaP: Zn quantum dot nuclear solution multiple times at intervals for a reaction, and obtaining the InP / GaP / ZnS nucleocapsid quantum dots. The preparation method is simple in synthesis process, the quantum yield can reach 60-90%, and the fluorescent wavelength range is 510-650 nm; the InP / GaP / ZnS nucleocapsid quantum dots prepared by the preparation method are thick in shell and good in stability.

The invention relates to antibacterial functional fibers and belongs to the field of polymer material. In the invention, carrier fibers and aqueous solution of an inorganic metal antibacterial agent are mixed and stirred at a constant temperature of 0 to 100 DEG C for 10 minutes to 24 hours first, then the fibers are taken out and washed by deionized water till the pH value of the fibers is 6.5 to 7.5, and finally the fibers are dried at 40 to 60 DEG C to give the target product. In the invention, the raw materials are widely available, the synthesis process is simple, the synthesis process is easy to control, and industrial production is easy to realize. The fibers have a broad antibacterial spectrum and long-lasting antibacterial performance, is safe and reliable, and can be made into health-care underwear, insoles, operation clothes, nurse clothes, medical gauzes and the like. The fibers can also be made into nonwoven fabrics used for making filter elements of air purifiers for killing bacteria and germs in the air, and therefore have a promising application prospect.

The invention provides a preparation method of a water-dispersive ternary mixed-crystal nano titanium dioxide photocatalyst. The preparation method comprises the following steps of: adding a titanium precursor into an absolute alcohol solvent at a room temperature, and uniformly stirring to obtain a titanium precursor alcoholic solution; then adding an acid hydrolysis inhibitor into the obtained titanium precursor alcoholic solution, and uniformly stirring the acid hydrolysis inhibitor and the obtained titanium precursor alcoholic solution, thereby obtaining a mixed solution; adding alcohol aqueous solution into the obtained mixed solution, uniformly stirring the alcohol aqueous solution and the obtained mixed solution, and standing for 1-20 minutes, thereby obtaining a gel; performing solvent thermal reaction on the gel at a temperature of 140-200 DEG C for 2-24 hours, then naturally cooling the reactant mixture to room temperature, and performing centrifugalizing, washing, vacuum drying and grinding, thereby obtaining a target product. Due to adoption of synthesis process based on a one-pot method, the preparation method is high in productivity, low in energy consumption and free from pollution; the product can form a nano dispersion in water and has quite high catalytic activity on organic sewage under a condition of visible lights.

The present invention is the synthesis process of Ti-Si molecular sieve, TS-1 molecular sieve, and belongs to the field of inorganic chemical synthesis. The materials, including solid silica gel, Ti(SO4)2, organic alkali template and water, are prepared into TS-1 molecular sieve via a three-step reaction process, including the preparation of solid silica gel and Ti(SO4)2 mixture, the preparationof reaction mixture and hydrothermal crystallization, and routine filtering, washing, drying and roasting. Inside the solid silica gel and Ti(SO4)2 mixture, Ti(SO4)2 is single-layer dispersed in thesurface of solid silica gel. The process has the advantages of cheap materials, no need of hydrolysis, less consumption of organic template agent, easy-to-control process, high repeatability, high yield and low cost.

The invention specifically relates to silicon carbide powder and a preparation method thereof. According to a technical scheme, the preparation method comprises the following steps of: uniformly mixing 5-20 percent by weight of nano-silicon dioxide or silica micro-powder, 0.5-2.5 percent by weight of carbon black or amorphous graphite powder, 70-88 percent by weight of an alkali metal chloride and 5-15 percent by weight of aluminum powder serving as raw materials; putting the uniformly-mixed raw materials into a tubular electric furnace, raising the temperature to 800-1,000 DEG C at the temperature raising rate of 4-10 DEG C per minute under the atmosphere of argon, and preserving heat for 2-10 hours; and putting an obtained product into nitric acid of which the concentration is 2-5 mol / L for soaking for 3-8 hours, filtering, cleaning with deionized water till the pH value of a cleaning solution is 7.0, and drying at the temperature of 110 DEG C for 8-24 hours to obtain silicon carbide powder. The method has the characteristics of low reaction temperature, simple process, controllable synthesis process, low production cost, and the like; and the prepared silicon carbide powder has the characteristics of high crystallization, high product purity, freeness from an impure phase and powder particle size of 50-200 nanometers.

The invention discloses water-soluble rare-earth terbium ion-doped cerium fluoride nanocrystallines and a preparation method thereof, and belongs to the technical field of fluorescent nano-crystalline materials and hydrothermal chemical method synthesis thereof. The rare-earth terbium ion-doped cerium fluoride nanocrystallines are rod-shaped or cube-like; and the polyethyleneimine is coated on the surfaces of the nanocrystallines. The preparation method comprises the following steps of: mixing cerium nitrate hexahydrate, terbium chloride hexahydrate, the polyethyleneimine and ethylene glycol in a certain ratio; reacting for 1 to 12 hours in a baking oven at the temperature of 160 to 240 DEG C; cooling a reaction product; washing the reaction product with water and ethanol; and drying in vacuum. The product has very high solubility, adjustable and controllable appearance, high particle stability and high fluorescence quantum yield, and also can be dispersed in different solvents. In the method, raw materials are cheap and easy to obtain; the process is simple; the cost is low; the process repeatability is high; and the nanocrystallines have a potential application value in the field of biomarkers.

The invention discloses Isooctyl nitrate compounding method. It includes the following steps: mixing nitric acid and sulfuric acid with mol ratio 1:1-5; adding latent solvent with 10-50% volume ratio to the mixed acid or isooctyl alcohol; adding isooctyl alcohol into mixed acid or adding the mixture of isooctyl alcohol and latent solvent into the mixed acid; reacting for 0.5-1h; static layering; discharging acid liquor; water washing; alkali washing; water washing to neutrality; separating ester from latent solvent; and drying by dryer. The latent solvent can be cycling using.

The invention discloses a method for mixing polyester-ether macromonomers for preparation of a polycarboxylic acid water reducer, and belongs to the field of a water reducer. According to the method, two macromonomers and maleic anhydride polyethylene glycol are taken as raw materials to produce the polycarboxylic acid water reducer through multiple polymerization in the presence of acrylic acid, a chain transfer agent and a reducing agent. By use of influence of the structure and performance of the polycarboxylic acid water reducer by structure difference of polyether macromonomers and ester macromonomers, water reducing ratio and slump retention property of the polycarboxylic acid water reducer can be balanced, and air entraining ratio of the polycarboxylic acid water reducer can be effectively reducted by use of ester ether mixed structure. The method has the advantages of simple process, convenient control, easy industrialization, low cost, safety and environmental protection.

The invention relates to an acrylic acid modified sulfonate-based water-reducible alkyd resin and preparing method thereof. The preparing method comprises the following steps that: dihydric alcohol or polyol, partial polybasic carboxylic acid or acid anhydrides and functional monomer containing the sulfonate-base are subjected to esterification till the acid value is qualified; vegetable oil fatty acid and residual polybasic carboxylic acid or acid anhydrides are added to continue the esterification till the acid value is qualified; glycidyl ester compound containing acrylic acid group is added to continue the esterification till the acid value is qualified; cosolvent is added to dilute; and then mixed liquor of acrylic acid monomers and initiator is added drop by drop; after the reactiontotally completes the acrylic acid modified sulfonate-based water-reducible alkyd resin can be obtained. The alkyd resin of the invention has the advantages of good water dilution, high solid content, excellent paint film water proofness after the resins are made into paint.

The invention relates to a method for directly synthesizing a pure solid high-performance polycarboxylate water-reducer in one step, belonging to the field of water-reducers. According to the method, the pure solid high-performance polycarboxylate water-reducer is prepared by taking an acrylic compound and unsaturated polyoxyethylene ether as polymerization reaction monomers, adding a molecular weight regulator and carrying out free-radical polymerization reaction under the action of an initiator and under a solvent-free environment. The method disclosed by the invention is strong in controllability, high in polymerization degree, low in cost, environment-friendly and pollution-free, achieves the purpose of preparing the absolutely anhydrous pure solid polycarboxylate water-reducer by bulk polymerization, not only has the fluidity and holding property of cement paste, cement adaptability and concrete application performance which are similar to those of a polycarboxylate water-reducer prepared from a common solution by polymerization and can be prepared into any concentration of solution according to actual demands as the pure solid high-performance polycarboxylate water-reducer prepared by direct polymerization is an anhydrous pure solid, but also is free of postprocessing working procedures, such as heat drying or solvent separation and is more convenient to transport, saved in transport cost and favorable in market competitiveness and application prospect.

This invention relates to a method for preparing a star-shaped polycarboxylate superplasticizer by the first esterification step with polyol and (meth)acrylic acid as main reactants and the second polymerization step. In the first step, the star-shaped polymerizable active ends were synthesized by esterification between polyol and (meth)acrylic acid in the presence of catalyst. In the second step, the final star-shaped polycarboxylate superplasticizer was prepared by radical polymerization among the product obtained in first step, unsaturated polyoxyethylene ethers, molecular weight regulator and unsaturated carboxylic acid in the presence of initiator. The production process of this invention exhibits some characteristics including simple, easily controllable, high polymerization degree, low cost and pollution free. The star-shaped molecular structure of polycarboxylate superplasticizer can be achieved through synthesizing active “core” by esterification and “arm” by radical polymerization. It showed better cement paste fluidity and fluidity retention, which manifested as better adaptability to cement and application performance in concrete, than both traditional linear and comb-shaped polycarboxylate superplasticizer at common or lower dosage.

The invention relates to a controllable short-process preparation method of nano titanium dioxide, and belongs to the field of material preparation. The preparation method comprises the following steps that: (1) butyl titanate is added into a hydrogen peroxide solution in a water bath for reaction for 0-1200min at the water bath temperature of -5-40 DEG C to form light orange gel under a stirring condition; the molar ratio of Ti to H2O2 is 1:(2-30); and (2) isopyknic deionized water is added into the light orange gel for heating reflux to obtain a sediment; and the sediment is subjected to centrifugal separation, and dried below 120 DEG C or roasted at 400-700 DEG C for 30-240min to form nano titanium dioxide powder. With the adoption of the preparation method for preparing nano titanium dioxide, the preparation time can be shortened; reaction and gelling processes can be controlled; an external heating source is not required; a chemical agent can be utilized efficiently; the introduction of impurities can be reduced; prepared nano titanium dioxide has a good photocatalytic performance; and the method has a good market application prospect.

The invention discloses a double-component aqueous adhesive for an automotive interior and a preparation method of the double-component aqueous adhesive. The adhesive is a double-component aqueous adhesive of which a component A is synthesized by firstly introducing sulfonate to a polyurethane prepolymer molecular chain from an oligomer polyhydric alcohol, a nonionic hydrophilic monomer, a polyisocyanate, a micromolecule chain extender, a sulfonate-containing hydrophilic chain extender or a polyhydric alcohol with a sulfonic group, adding certain amounts of a silane coupling agent and an epoxy resin, carrying out uniform stirring, adding water, carrying out stirring emulsification, adding an amino type chain extender, an epoxy group and -NCO after emulsification, and by carrying out a reaction so as to obtain a polyurethane emulsion with amino; a component is an aqueous epoxy resin; the component A and the component B are mixed according to a certain ratio; and an aqueous thickening agent is additionally used to adjust the viscosity of the emulsion to form a novel adhesive system for bonding automotive interior materials. The double-component aqueous adhesive has the characteristics of being good in primary viscosity, thermal resistance and environment change resistance stability and free of smell, and use requirements on the automotive interior materials can be met.

The present invention discloses a sea urchin-like lithium titanate microsphere preparation method, which comprises: adding metal titanium powder to a sodium hydroxide solution, stirring, carrying out a hydrothermal reaction at a temperature of 80-260 DEG C, carrying out centrifugation separation on the obtained precipitate, drying the precipitate to obtain a titanium dioxide precursor, adding a lithium salt and the titanium dioxide precursor to an ethanol and deionized water mixed solution, stirring to obtain an emulsion, carrying out a hydrothermal reaction, carrying out centrifugation separation on the obtained precipitate, drying to obtain white powder, carrying out a calcining heat treatment at a temperature of 300-1000 DEG C, and cooling to a room temperature to obtain the sea urchin-like lithium titanate microsphere. The method of the present invention has the following beneficial effects that: the sea urchin-like lithium titanate microsphere having the micro-nano grading structure is provided, and has characteristics of high discharge specific capacity and excellent rate cycle performance.

The invention relates to the technical field of concrete additives, in particular to a solid polycarboxylate superplasticizer as well as a preparation method and application thereof. According to thepreparation method, an unsaturated carboxylic acid and a liquid polyether monomer are subjected to direct free radical polymerization reactions in a solvent-free environment, and then the solid polycarboxylate superplasticizer which is excellent in property is prepared. By adopting the preparation method, a body polymerization mode is implemented, no solvent or medium is used in the whole process,and a common method that water or an organic solvent is added at an early stage and is removed at a later stage is effectively improved; the obtained solid polycarboxylate superplasticizer not only is convenient to transport, but also has properties superior to those of solid polycarboxylate superplasticizers in the market.

The invention discloses a system and method of multi-element pulsed laser deposition for synthesizing a composite material in batches in the field of materials science. The method comprises the following steps of: using several beams of high energy laser, focusing the high energy laser beams and evaporating different source material targets by the focused high energy laser to generate different laser plasma beams, and finally depositing the source material unevenly on a substrate. The system and the method provided by the invention are simple and easy to use and have the characteristics of low cost, high efficiency, strong coordination and so on. The system and the method can be used for large-batch material synthesis in novel material research.

The invention discloses a preparation method of a polycarboxylic acid water reducer for finish concrete. The preparation method comprises the following steps: (1) allowing diethylenetriamine and maleic anhydride to react under the action of a catalyst to prepare a bright red viscous pre-polymer solution; and (2) copolymerizing the pre-polymer solution, unsaturated polyoxyethylene ether, a sulfoacid monomer and unsaturated carboxylic acid under the action of a redox initiation system and a chain transfer agent to prepare a polycarboxylic acid type water reducer for finish concrete. The water reducer and one or more of a defoaming agent, an air entraining agent, a retarder and a viscosity adjusting agent are compounded and then doped into concrete to prepare finish concrete which is high in construction performance, excellent in wrapping property and can be used for realizing the mirror effect.

The invention relates to the lot synthesis method for nano / micron ZnO hollow ball. Wherein, with Zn powder or ZnO powder as material, using simple chemical gas phase deposition to synthesize directly the product; adjusting the evaporating temperature of material, product deposition temperature or adding catalyst to realize original assembly synthesis. The product has well physical chemical performance and wide application in electronic device or other fields.

The invention discloses a synthesis method of a polycarboxylic acid high-performance water reducing agent of a star-like structure, belonging to the field of a water reducing agent. According to the synthesis method, polybasic alcohol, (methyl) acrylic acid, a polyethylene glycol compound and the like are used as esterification raw materials, and the polycarboxylic acid high-performance water reducing agent of the star-like structure is prepared through a sequential esterification and polymerization method, i.e., the (methyl) acrylic acid and the polybasic alcohol are used as reactants, a star-like polymerizable active end is prepared through esterification reaction under the action of a catalyst, and then the polycarboxylic acid high-performance water reducing agent is prepared from the star-like polymerizable active end and esterification macromolecule, a molecular weight regulator and an unsaturated carboxylic acid monomer under the action of an initiator through free radical polymerization reaction. The synthesis method has the advantages of simplicity, easiness in control, high polymerization degree, low cost, no pollution, capability of realizing the polycarboxylic acid high-performance water reducing agent of the star-like structure connected with a plurality of polycarboxylic acid molecules, and more superior cement paste fluidity and holding capacity, good cement adaptability and concrete application performance compared with the conventional linear and comb-shaped polycarboxylic acid water reducing agent in the case of normal and low added amount.

The invention provides a composite material MoO3 / Polyaniline / Ti3C2Tx and a preparation method thereof. The preparation method includes the steps that 1, Ti3AlC2 powder is completely immersed in an HF solution with the volume fraction of 40%, centrifugation is conducted, and powder is obtained and dried; 2, ammonium molybdate tetrahydrate and tartaric acid are completely dissolved in water, and a water solution is obtained; 3, the powder Ti3C2Tx is added into the water solution; 4, suspension liquid obtained in the step 3 is centrifuged and dried in a vacuum drying oven; 5, the powder obtained in the step 4 is sintered and subjected to heat preservation, and a MoO3 / Ti3C2Tx composite material is obtained; 6, the obtained powder is ultrasonically dispersed in distilled water, aniline is added, and stirring is conducted in an ice bath; 7, (NH4)2S2O4 is dissolved in HCl, cooling is conducted, and the mixture is added into suspension liquid obtained the step 6; 8, suspension liquid obtained in the step 7 is centrifuged, washed, subjected to alcohol washing and freeze drying, and the target object is obtained. Due to the fact that the material is high in composition adjustability, the preparation process is simple and the synthesis process is easy to control, the application range of the composite material to an electrode material is widened.

The invention provides a preparation method for a lithium iron phosphate material of a positive electrode of a lithium ion secondary battery. The preparation method comprises the following steps of: evenly mixing an iron source, a carbon source, a lithium source, a phosphate radial source and doping ions, conducting a drying procedure to obtain lithium iron phosphate precursor mixture, warming and heating the mixture in reducing atmosphere at the speed of 0.5-10 DEG C / min, preserving heat at 300-400 DEG C for 2-5hours, calcining at 500-850 DEG C for 3-28 hours, conducting furnace cooling to room temperature, smashing and classifying to obtain the lithium iron phosphate material of the positive electrode. The preparation method realizes the adoption of the low-cost ferric iron source, and achieves the doping of metal ions and further synthesis of the lithium iron phosphate composite material, and the prepared lithium iron phosphate material of the positive electrode is good in rate capability, easy for the synthesis process to control, and suitable for industrialized production, the prepared material is even in particles, high in crystallinity degree, good in discharge capacity, and stable in recycling property.

The invention discloses a preparation method for a cationic side chain esterified-grafted highly-mud-resistant cement dispersing agent, and belongs to the field of dispersing agents. The preparation method comprises the following steps: performing free radical polymerization on an unsaturated carboxylic acid monomer serving as a reactant to obtain a polycarboxylic acid main chain under the action of an initiator and a chain transfer agent, performing free radical polymerization on an unsaturated cationic quaternary ammonium salt monomer serving as a reactant to obtain a hydroxyl-terminated cationic side chain under an oxidization-reduction initiation system formed by high-valence ceric salt and alcohol, and performing esterification-grafting reaction on the polycarboxylic acid main chain, the hydroxyl-terminated cationic side chain and a polyethylene glycol compound in the presence of a catalyst. According to the preparation method, a process is simple and easy to control, and the preparation method is low in cost, energy-saving, efficient, environment-friendly and free of pollution; a composite side chain structure is modified and synthesized by a molecular structure design, so that side chain steric hindrance effects are successfully achieved, cationic charge arrangement is successfully implemented, water reduction and slump retaining characteristics and clay side effect suppression capabilities higher than those of an ordinary polycarboxylic acid water reducing agent are achieved, and the dispersing agent has broad market prospect and great popularization and application potential.

The present invention provides an anionic and nonionic mixed aqueous polyurethane dispersion body and a preparation method thereof, wherein the raw material components comprise, by weight, 80-150 parts of macromolecule polyol, 35-50 parts of isocyanate, 10-20 parts of dihydroxyl polyethylene oxide, 2-4 parts of a carboxylic acid type hydrophilic chain extender, 2-5 parts of a neutralizing agent, 2-10 parts of a small molecule polyol chain extender, and 2-10 parts of a small molecule amine post chain extender. According to the present invention, the organic solvent is not required to be added during the preparation of the aqueous polyurethane dispersion body, such that the environmental pollution can be avoided; the main chain of the prepared anionic and nonionic mixed aqueous polyurethanedispersion body contains the Y-shaped side chain non-ionic hydrophilic component, such that the aqueous polyurethane dispersion body has the uniformly-distributed hydrophilic chains, and further has advantages of excellent performance and improved stability; and the side chain of the aqueous polyurethane dispersion body contains the carboxylic acid type hydrophilic component so as to optimize thewater resistance of the aqueous polyurethane dispersion body.

The invention discloses a preparation method of an ultra-thin carbon nano tube wave-absorbing coating material. According to the preparation method, surface strong oxidation treatment is carried out on a carbon nano tube by a method of mixing strong acid with a strong oxidant, and a modified carbon nano tube with a special ''wool-shaped'' surface appearance is prepared. Different high polymer materials are selected as a matrix, and the ultra-thin broadband carbon nano tube wave-absorbing coating material is obtained by adjusting the proportion relation between the content of an absorbent and the high polymer materials. The coating material prepared by the method overcomes the defects of large thickness, large mass, narrow absorption frequency band, complex preparation process and the likeof a conventional wave-absorbing coating material. When the thickness of the coating is 1.0 mm or below, full-band absorption of the X wave band and the Ku wave band of radar waves of -4dB or below can be realized, and the frequency width of reflection loss less than -10dB can reach 5.23GHz.

The invention discloses a preparation method of an iron carbide composite electrode material coated with nitrogen and sulfur doped with carbon. The method comprises the following steps of: (1) mixingan iron-containing compound, thiourea and glucose, dissolving the mixture into a solvent for stirring and heating until dried powder is obtained; (2) performing heat treatment in an inert atmosphere for cooling to obtain black powder; (3) adding an acid solution for heating and stirring, filtering to remove filter residues to wash until the solvent is neutral, cooling and drying the residue obtained after washing to obtain an iron carbide composite electrode material coated with nitrogen and sulfur doped with carbon. The method is simple in process, greatly limits the agglomeration of the ironcarbide nanoparticles, is easy to control of the synthesis process and low in manufacturing cost, and can be applied to fields of energy storage and conversion research such as lithium ion batteries,electrocatalytic oxygen reduction.