793 results about "Sodium hypophosphite" patented technology

The invention discloses a chemical nickel-plating method for carbon fiber, which is designed for overcoming the disadvantages of high cost, a large number of process steps and poor operability existing in the prior art. In the method, a chemical plating process is adopted; and a pre-treatment is performed on a raw material and chemical plating solution is prepared before the chemical plating. The pre-treatment process comprises the steps of: calcining by using a muffle furnace to remove glue; soaking in solution of absolute ethanol to remove oil; performing surface roughening and activating treatment by using solution of sodium hydroxide and solution of silver ammonia; sensitizing by using a sensitizer, namely stannous chloride; and performing surface reduction by using solution of sodium hypophosphite. The chemical plating solution consists of nickel sulfate hexahydrate, sodium hypophosphite, sodium pyrophosphate and sodium citrate. The chemical nickel-plating on the carbon fiber is finished by placing a pre-treatment product of the chemical plating into the chemical plating solution, and reacting, standing, filtering and drying under a chemical plating condition. The method has the characteristics that: the product has a uniform surface, a compact plating layer and uniform particles.

A tampon pledget includes crosslinked cellulose fibers having microstructures treated to provide improved absorbency and higher wet strength. The fibers are treated with a crosslinking agent to provide at least one of a molecular weight between crosslinks of from about 10 to 200 and a degree of crystallinity of from about 25% to 75%. The crosslinking agent includes citric acid in 1% by weight. The crosslinking agent may further include sodium hypophosphite in 1% by weight. In another embodiment, the crosslinking agent may be a difunctional agent including a glyoxal or a glyoxal-derived resin. In still another embodiment, the crosslinking agent is a multifunctional agent including a cyclic urea, glyoxal, polyol condensate. The crosslinking agent is added in an amount from about 0.001% to 20% by weight based on a total weight of cellulose fibers to be treated and, preferably, in an amount of about 5% by weight.

The present invention provides a process for producing copper nanoparticles, comprising steps of: a) reacting an aqueous solution containing a reductant with an aqueous solution of a copper salt while stirring for 1-8 min, wherein the reductant being one or more selected from a group consisting of hydrazine hydrate, sodium borohydride and sodium hypophosphite; b) adding an apolar organic solution containing the extracting agent and continuing the stirring for 0.5-1.5 hrs, said extracting agent being one or more selected from the group consisting of alkyl dithiocarbonic acid and salts thereof, O,O′-dialkyl dithiophosphoric acid and salts thereof, and dialkylamino dithioformic acid and salts and said apolar organic solution being one selected from the group consisting of benzene, toluene and straight or branched alkanes having 6-12 carbon atoms, wherein the alkyl having 6-20 carbon atoms; and c) post-treating the reaction product to obtain copper nanoparticles.

The invention discloses a polycarboxylate superplasticizer and a preparation method thereof. The raw materials of the polycarboxylate superplasticizer comprise the following components in parts by weight: 190-200 parts of a polyether monomer, 15-25 parts of unsaturated acid, 1-5 parts of hydroxyl alkyl acrylate, 1.5-3.5 parts of an oxidizing agent, 1-3 parts of sodium hypophosphite, 0.5-2.5 parts of tartaric acid, 325 parts of water and 11-21 parts of 30-32% sodium hydroxide by mass concentration, wherein the polyether monomer is 600-3000 methylallyl polyoxyethylene-polyoxypropylene or isopentenol polyoxyethylene ether. The preparation method of the polycarboxylate superplasticizer, disclosed by the invention, is carried out in a temperature range of 5-40 DEG C and can be used for solving the problem that the initiating efficiency is relatively low at a relatively low temperature when a single reducing agent is used, meanwhile, the dropwise adding time can be shortened, the production cycle is shorter, the energy consumption is relatively low and the production cost is lowered.

The invention discloses a mud-resistant polycarboxylic acid water reducer which is prepared from the following components: allyl polyoxyethylene polyoxypropylene ether, components R, R1 and R2, a chain transfer agent, an initiating agent R3 and water, wherein the component R is one or more of maleic anhydride, sodium methallyl sulfonate, vinyl acetate, itaconic acid, itaconic anhydride and fumaric acid; R1 is one or a mixture of two of acrylic acid and methylacrylic acid; R2 is one or more of ascorbic acid, sodium formaldehyde sulfoxylate, ferrous sulfate, tin sulfate, sodium hypophosphite, sodium hydrogen sulfite and oxalic acid. The invention further discloses a preparation method for the mud-resistant polycarboxylic acid water reducer. The mud-resistant polycarboxylic acid water reducer has the following benefits: the water solubility and the steric hindrance of polycarboxylic acid are effectively kept; a large amount of non-hydrophilic structures on branch chains can be used for effectively preventing soil interlayer adsorption, so that the adsorption speed and effect are greatly reduced and the mud-resistant purpose is achieved.

The invention relates to a method for preparing aluminum hypophosphite. The method includes the following steps of firstly, preparing sodium hypophosphite solution with concentration of 2-6mol/L, adjusting pH (potential of hydrogen) to be 3-5 preferentially within 3-6.5; secondly, preparing aluminum sulfate solution; and thirdly, subjecting the sodium hypophosphite solution and the aluminum sulfate solution to reaction by heating on the acid condition to generate aluminum hypophosphite. The aluminum sulfate is added into the sodium hypophosphite solution for reaction within a certain temperature range, so that harms caused by volatilization of hypophosphorous acid during preparing of the aluminum hypophosphite are avoided, operation is simplified, yield of products is high, cost is low and industrialization is easy to realize.

The invention relates to a nickel-phosphorus chemical precipitation plating layer of an aluminium alloy, mainly containing the following components in content by weight: 20-30 grams/litre of hexahydrated nickel sulphate, 20-30 grams/litre of sodium hypophosphite, 15-20 grams/litre of sodium acetate, 6-10 grams/litre of butane diacid, 30-50 grams/litre of complexing agents, 20-60 PPM of stabilizingagent and 30-100 PPM of plating midbodies. The nickel-phosphorus chemical precipitation plating layer has the advantages of fast precipitation, well combining force of a plating layer, brightness andcompactness of the plating layer, excellent stable property of tank liquor, long service life, easy maintenance, and the like.

The invention provides a silvered aramid conductive fiber and a preparation method thereof. The preparation method is conducted according to the steps as follows: a. coarsening: coarsening the aramid fiber through putting the fiber into a mixed solution of sodium hydroxide, absolute ethanol and the balance of water, and neutralizing the fiber by rinsing; b. hydrolyzing: hydrolyzing the coarsened aramid fiber by putting the fiber into an acid solution; c. activation of palladium salt: activating the hydrolyzed aramid fiber subjected to activation of palladium salt in step b by putting the fiber into a mixed solution of hydrochloric acid, palladium chloride, stannous chloride and the balance of water; d. reducing: reducing the palladium salt activated aramid fiber in step c by putting the fiber into a mixed solution of hydrochloric acid, sodium hypophosphite and the balance of water; e. chemical silvering: chemical silvering the reduced aramid fiber in step d by putting the fiber into a chemical silvering solution of silver nitrate, sodium hydroxide, aqua ammonia, a complex agent, a reducing agent and the balance of water; f. drying: drying the chemical silvered aramid fiber in step e in the conventional manner to obtain the silvered aramid conductive fiber.

The invention provides a novel method for preparing nickel phosphide (Ni12P5) by the low-temperature solvothermal method. The method of the invention is characterized by dissolving anhydrous nickel chloride as a nickel source and sodium hypophosphite as a phosphorus source in a high-boiling-point organic solvent at the room temperature, stirring the materials until the organic solvent is transparent, sealing the organic solvent in a high-pressure kettle and heating up to 140-240 DEG C and reacting for certain time to obtain Ni12P5. The method of the invention is characterized by using a high-boiling point organic substance as the solvent, the reaction conditions are simple and mild and the generated Ni12P5 is the nano-particle with the size being 50nm to 200nm and the specific surface area being larger. The method is favorable for hydrodesulfurization, selective hydrogenation and other catalytic hydrogenation reactions, thus having wider application range.

The invention discloses a quaternary polymeric form corrosion and scale inhibitor which consists of maleic anhydride, hydroxy-propyl acrylate, acrylic acid, sodium alkyl sulfonate, sodium peroxydisulfate, sodium hypophosphite, isopropyl alcohol and water. The invention also discloses a preparation method of the quaternary polymeric form corrosion and scale inhibitor. The corrosion and scale inhibitor has good performance in inhibiting calcium carbonate scale, calcium sulphate scale, calcium phosphate scale and zinc scale and good dispersing performance for dispersing ferric oxide and is also characterized by corrosion resistance, high temperature resistance, stable molecule structure and low phosphorus content; the whole production process has no emission of 'the three wastes'. The technique of the product of the invention for treating circular cooling water is simple and the product of the invention has the advantages of little dosage, low cost, good effect and good economic benefit and wide social benefit.

The invention relates to the preparation and storage method of silver nano-particles for conductive adhesive, in particular to a method for preparing silver nano-particles by reducing high-concentration silver nitrate by adopting a chemical liquid-phase method. The method comprises the following steps: mixing sodium hypophosphite, polyvinyl pyrrolidone and sodium hexametaphosphate to obtain reduction solution, adding sulfuric acid dropwise to adjust pH value, adding silver nitrate solution into the reduction solution under magnetically stirring to obtain silver colloid, standing, centrifugally separating, recovering filtrate, concentrating, centrifugally separating, washing the solid, vacuum-drying to obtain silver nano-particles, sealing and packaging, and storing at low temperature. The method adopts high-concentration silver nitrate solution, and has the advantages of simple process flow, high yield of silver powder, short production cycle and good safety. In the separation process, the filtrate can be recovered to improve the coefficient of recovery of silver powder. The silver nano-particle has spherical shape, uniform particle diameter, narrow distribution, high purity, good dispersibility, good storage stability and long storage time without oxidization, and can be used for conductive filler such as conductive adhesive.

The invention discloses a foamed nickel self-supported flake-shaped Ni3P/C composite material for a sodium ion battery negative electrode and a preparation method for the composite material. According to the composite material, the flake-shaped Ni3P is uniformly growing on the foamed nickel; and the Ni3P is uniformly coated with a C film. The preparation method for the composite material comprises the steps of taking a nickel compound as the raw material, and uniformly growing a flake-shaped nickel hydroxide layer on the surface of the nickel compound through a hydrothermal method; then taking sodium hypophosphite as a phosphorus source, and performing thermal insulation at a temperature of 300 DEG C for 2h to prepare the foamed nickel self-supported flake-shaped Ni3P material; and finally, performing carbon coating on the foamed nickel self-supported flake-shaped Ni3P material to obtain the foamed nickel self-supported flake-shaped Ni3P/C composite material. The sodium ion battery prepared from the Ni3P/C composite material prepared by the invention has excellent specific capacity, rate capability and stable cycling performance; and in addition, the preparation method is simple and feasible, wide in raw material resources and suitable for industrial production.

The invention provides a formulation of medium-temperature acidic electroless nickel-phosphorus alloy, which is characterized in that the formulation is as follows: 25 to 30 grams of nickel sulfate per liter, 25 to 35 grams of sodium hypophosphite per liter, 12 to 18 grams of sodium acetate per liter, 0.5-1.3 milligrams of thiourea per liter, 7 to 13 milliliters of lactic acid per liter, 7 to 13 milliliters of acetic acid per liter, 4-10 grams of organic acid per liter, 5-16 milligrams of potassium iodide or potassium iodate per liter, and the loadage is between 0.5 and 1.5 dm<2>/L. The invention has the advantages that: the formulation improves the stability of a plating solution, obviously improves plating rate, has good corrosion resistance and the comprehensive properties of plating; the stability of the plating solution can reach over 1800 s; the stability of periodic experiments is more than ten periods; the corrosion resistance of the plating reaches over 130 s; and the hardness of the plating reaches 480 HV.

The invention discloses an antibacterial wash-and-wear fire-retardant finishing liquid which is prepared from the following raw materials in parts by weight: 10-15 parts of glyoxal, 10-15 parts of citric acid, 5-8 parts of cyclic phosphate, 5-8 parts of a licorice extract, 3-5 parts of chitosan, 2-3 parts of magnesium chloride, 2-3 parts of sodium hypophosphite, 1-2 parts of a penetrant, 1-2 parts of a coupling agent, 1-2 parts of a softener, 1-2 parts of ethylene glycol, 1-2 parts of a fiber protecting agent, 1-2 parts of a pH adjusting agent and 1-2 parts of a dispersant. The prepared multifunctional antibacterial finishing liquid is environment-friendly and free of pollution, has good efficacies of being wash-and-wear, shrink-proof, antibacterial and flame-retardant, and can meet the requirements of people on various functional aspects of textiles.

The invention relates to a plating solution for chemical plating nickel-tungsten-phosphor alloy, comprising nickel vitriol of 24 to 28 g/l, sodium citrate of 40 to 70 g/l, gluconic acid sodium salt of 20 to 30 g/l, ammonium sulfate of 30 to 40 g/l, sodium pyroborate of 5 to 15 g/l, sodium tungstate of 30 to 50 g/l, sodium hypophosphite of 20 to 28 g/l, potash iodate of 10 to 20 mg/l, thiourea of 0.5 to 1.5 mg/l and sodium dodecyl sulfate of 5 to 15 mg/l. The plating solution is characterized in that: the chemical plating method using the plating solution comprises the following steps that: the pH value of the plating solution is adjusted to 8 to 9, and then the plating solution is heated to 80 to 90 degree centigrade, and then the processed plating articles are dipped into the plating solution; the time of dip plating is determined by the required plating layer thickness. The plating solution for chemical plating nickel-tungsten-phosphor alloy has the advantages of higher stability and higher plating speed.

The invention discloses a method for degrading methyl orange by use of perovskite/polysaccharide composite photocatalyst. The method comprises the following steps: preparing perovskite by utilizing nitrate of La, Cu and Fe, adding the perovskite and chitosan into an acetic acid solution, and performing ultrasonic treatment; drying to form a film to obtain a perovskite/chitosan composite photocatalyst; or adding xylan into distilled water, adding sodium hypophosphite and citric acid solution, adding perovskite, performing ultrasonic treatment, dehydrating, crosslinking to form a film, and washing with ethanol to obtain a perovskite/xylan composite photocatalyst; adding the composite photocatalytic material into the methyl orange solution, respectively reacting for 470-490 minutes at normal temperature in ultraviolet radiation. The polysaccharide used in the method is formed by compounding the catalyst and polysaccharide respectively with chitosan and xylan, the methyl orange photocatlytic degrading capability of the polysaccharide can be improved. The polysaccharide has the advantages of high catalytic efficiency, strong photo-response performance, regeneration, recycling and the like.

The invention discloses s preparation method of a hydroxypropyl guar gum/nanocellulose cross-linked adsorption film. The method takes hydroxypropyl guar gum and microcrystalline cellulose as main raw materials, and comprises the steps: thinning the microcrystalline cellulose in a nano grinder and a high-strength ultrasonic wave generator successively to prepare nanocellulose, then respectively dispersing and dissolving the nanocellulose and hydroxypropyl guar gum in maleic acid, then adding maleic anhydride and sodium hypophosphite, stepwise heating to carry out esterification and cross-linking reaction, centrifuging and defoaming the reactant, shaping the reactant in a mold, forming a film by drying, and cleaning and freeze-drying the film to obtain the adsorption film. The film prepared by the method is light yellow and transparent, has good adsorptive capacity on copper ions, zinc ions, led ions, methylene blue and methyl violet, and simultaneously has higher mechanical properties.

The invention discloses a preparation method of a hollow Ni2P/Co2P/Fe2P nano-composite electrocatalyst. The method comprises the following steps: preparing a nickel-cobalt precursor, used as a template, by using nickel acetate, cobalt acetate and polyvinylpyrrolidone as reaction materials and ethanol as a reaction solvent, adding potassium ferricyanide, and preparing a hollow Prussian blue analogthrough room temperature stirring by using ethanol and water as reaction solvents; and phosphating PBA in a tubular furnace at a low temperature with sodium hypophosphite as a phosphorus source to prepare the hollow Ni2P/Co2P/Fe2P nano-composite material. The hollow Ni2P/Co2P/Fe2P nano-composite electrocatalyst prepared in the invention has the advantages of high repeatability, simple and high preparation process, and superior catalytic activity and stability in electrocatalytic oxygen evolution reactions.