290 results about "Sodium trimetaphosphate" patented technology

The invention generally provides a light weight composite gypsum board including a foamed low density set gypsum core, a top non-foamed (or reduced-foamed) bonding high density layer and a bottom non-foamed (or reduced-foamed) bonding high density layer, a top cover sheet bonded to the foamed low density set gypsum core by the top non-foamed (or reduced-foamed) bonding high density layer, and a bottom cover sheet bonded to the foamed low density set gypsum core by the bottom non-foamed (or reduced-foamed) bonding high density layer. The foamed low density set gypsum core and the non-foamed (or reduced-foamed) bonding high density layers are made from a gypsum slurry including stucco, pregelatinized starch present in an amount of about 0.5-10% by weight based on the weight of stucco, preferably a naphthalenesulfonate disperant present in an amount of about 0.1-3.0% by weight based on the weight of stucco, and preferably sodium trimetaphosphate present in an amount of about 0.12-0.4% by weight based on the weight of stucco. Other slurry additives can include accelerators, binders, paper fiber, glass fiber, and other known ingredients. The foamed low density set gypsum core is prepared having a density of less than about 30 pcf using soap foam in the gypsum-containing slurry. The combination of components provide a composite gypsum board having light weight and high strength. A method of making the composite gypsum board is also provided.

The invention generally provides gypsum-containing slurries including stucco, a hydroxyethylated starch, naphthalenesulfonate dispersant, and sodium trimetaphosphate. The naphthalenesulfonate dispersant is present in an amount of about 0.1%-3.0% by weight based on the weight of dry stucco. The hydroxyethylated starch is present in an amount of from about 0.5% by weight to about 10% by weight based on the weight of dry stucco in the formulation. The sodium trimetaphosphate is present in an amount of about 0.1%-0.4% by weight based on the weight of dry stucco. Other slurry additives can include accelerators, binders, paper fiber, glass fiber, and other known ingredients. The invention also comprises the gypsum-containing products made with such slurries, for example, lightweight gypsum wallboard, and a method of making lightweight gypsum wallboard.

The invention belongs to the technical field of medical preparations, and in particular discloses a compound microporous starch powder hemostat and a preparation method thereof. The compound microporous starch powder hemostat uses potato starch and sweet potato starch as raw materials. The preparation method comprises the following steps: performing pregelatinization and ultrasonic pretreatment on the potato starch and the sweet potato starch, and then performing enzymatic hydrolysis on the potato starch and the sweet potato starch respectively to make pores so as to prepare microporous starches of the potato starch and the sweet potato starch respectively; in the process of enzymatic hydrolysis to prepare the microporous starches, adopting a vacuum freeze-drying method for drying the starches; using sodium trimetaphosphate to crosslink starch molecules so as to strengthen the structure; and mixing the potato crosslinking microporous starch and the sweet potato crosslinking microporous starch according to certain proportion to obtain the compound microporous starch powder hemostat. The microporous starch prepared by the method has strong hydroscopic property and obviously improved water-absorbing speed; besides, compared with the prior single-starch polysaccharide hemostatic material, the ingredients of the compound have improved performance and good hemostatic effect.

A preparation method of a biodegradable mulching film is characterized in that: 1, according to the weight proportion, materials are prepared by taking the following components: 55-60 parts of polyethylene, 17-20 parts of cassava starch, 18-22 parts of corn starch, and 5-10 parts of a multielement biological degradation promoting agent; the polyethylene comprises the components by weight: 68-90 parts of 7050, and 10-32 parts of 1F7B; the multielement biological degradation promoting agent comprises the components by weight: 40-80 parts of a cross-linking agent, and 20-40 parts of a degradation accelerant; the cross-linking agent is an arbitrary combination of one or two of di(tert-butylperoxy isopropyl)benzene, sodium hexametaphosphate, sodium trimetaphosphate or sodium tripolyphosphate; the degradation accelerant is an arbitrary combination of one or two of a corn oil, a sunflower seed oil, an epoxidized soybean oil or manganese stearate; and 2, the preparation method comprises the following production steps: a, blending to obtain a degradation masterbatch; b, granulating the degradation masterbatch; c, carrying out blow molding to prepare a film; d, trepanning the biodegradable mulching film; and e, rolling up the biodegradable mulching film, carrying out seal package, and warehousing.

The invention relates to the field of composite fertilizers, in particular to an active microorganism coated slow release composite fertilizer, which is prepared from the following raw materials by weight part: 10-15 of 1250-2000 mesh diatomite, 10-12 of triple superphosphate, 15-18 of potassium dihydrogen phosphate, 20-22 of urea, 18-20 of ammonium carbonate, 10-12 of boric magnesium fertilizer, 14-15 of plant fallen leaves, 7-8 of soy bean residue, 0.02-0.03 of a JT strain, 1-2 of ammonium molybdate, 5-6 of Oenanthe javanica, 1-2 of freshwater shrimp shell powder, 10-12 of crop straw, 8-10 of peanut meal, 1-3 of radix isatidis, 6-8 of fermented chicken manure, 10-12 of porous starch, 1-3 of sodium trimetaphosphate, 4-6 of acrylic acid, 6-8 of polyvinyl alcohol, 0.1-0.2 of ammonium persulfate, 3-5 of cherry stone powder, 2-4 of orange peel, 15-18 of fermented alga liquid, and 4-5 of an additive. The composite fertilizer provided by the invention has wide material sources and comprehensive and rich nutrients, and in terms of the production technology, diatomite and an active slow release coating agent are utilized to form dual coating on nutrients, so that the fertility can be more lasting, and the soil vitality can be improved, plant diseases and insect pests can be reduced, and the efficacy of enhancing crop yield and quality can be achieved.

A process for preparing the high-purity raw breviscapine B includes such steps as loading the breviscapine in a container, adding water, adding pH regulator chosen from 15 compounds including sodium meta-phosphate, potassium meta-phosphate, sodium hypophosphate, potassium hypophosphate, etc to regulate pH=4-8, adding solvent, depositing, laying aside, filter, washing the deposit by solvent, transferring the deposit to a solvent solution, acidifying, filter, water washing and drying.

The invention provides a preparation method of an enhanced bacteriostatic and breathable composite fiber electrostatic spinning membrane. The preparation method includes the following steps that 6-8 parts of polyvinyl alcohol are weighed and dissolved in 100 parts of 60-80 DEG C deionized water, and a PVA water solution is prepared; (2), 4 parts of active bacteriostatic substances are added into the PVC water solution, the active bacteriostatic substances are formed by mixing cinnamon essential oil, allicin, tea polyphenol and thyme essential oil according to the mass ratio of (2-4):(1-3):(0.5-2.5):(0.4-2.4), then 0.5-1.5 parts of cyclodextrin and 1-3 parts of corn porous starch are added, after the materials are fully mixed and stirred for 5-8 hours, 5-10 parts of sodium trimetaphosphateand boric acid complex are added for crosslinking, the sodium trimetaphosphate and boric acid complex is formed by compounding sodium trimetaphosphate and boric acid at the mass ratio of 4:5 until thesolution is uniform, and a spinning solution is obtained; (3), the spinning solution is arranged on an electrostatic spinning machine for spinning, and a spinning membrane is obtained; (4), the spinning membrane is subjected to glutaraldehyde fumigation crosslinking, and after the spinning membrane is dried in the air, the composite fiber electrostatic spinning membrane is obtained.

The invention discloses an organic polymer heavy metal chelating flocculant as well as a preparation method and an application thereof. The organic polymer heavy metal chelating flocculant is prepared from the following raw materials in parts by weight: 100 parts of carboxymethyl starch, 5-20 parts of a crosslinking agent, 0.05-0.5 part of an initiator, 5-20 parts of acrylamide and 28-60 parts of carbon disulfide, wherein the crosslinking agent is adipic acid, phosphorus oxychloride or sodium trimetaphosphate. The organic polymer heavy metal chelating flocculant has the efficacies of both excellent heavy metal chelating precipitation and flocculation, has the advantages of rapidness in reaction speed, ideal effect of removing heavy metal ions, high treatment efficiency and the like, is low in dosage and cost and is capable of economically and efficiently treating sewage containing the heavy metal ions.

The invention discloses a chitosan composite preservative film and a preparation process thereof. Chitosan is used as the main component of the preservative film. The preservative film comprises the following components in parts by weight: 100 parts of the chitosan, 3,000-4,000 parts of 1% acetic acid solution, 1-5 parts of sodium trimetaphosphate, 30-50 parts of silica sol, 100-200 parts of glycerol, and 2-10 parts of oleic acid. By being improved through chemical and physical blending modification, the prepared preservative film has the advantages of being good in extensibility, flexibility, transparency, oxygen permeating coefficient and moisture permeability and the like; the preservative film disclosed by the invention has good biocompatibility with organisms; enzymatic degradation, oxidative degradation and acid degradation can be carried out under a certain condition; the final degradation products are oligomers, such as dimeric glucan, trimerical glucan and the like; the residual toxicily problem does not exist; and the preservative film has strong practicability in terms of fruit and vegetable freshness.

The invention provides a preparation method of composite modified starch, comprising: carrying out crosslinking by crosslinker sodium trimetaphosphate; and then esterfying by succinic anhydride. The invention also provides a composite modified starch prepared with the method and application thereof.

The invention discloses a water-based reflective heat insulation paint and a preparation method thereof. The water-based reflective heat insulation paint is prepared from an emulsion, nanoparticles, triazole, sodium trimetaphosphate, hydroxyethyl cellulose, an inorganic non-metal compound, a reflecting material, filler, a dispersant, a toughening agent, a binder, ethylene glycol and distilled water. The preparation method includes: firstly mixing distilled water and a dispersant, then conducting warm water bath heating, adding nanoparticles, the inorganic non-metal compound and the reflecting material in order, stirring the substances evenly, then sequentially adding an emulsion, hydroxyethyl cellulose, triazole and sodium trimetaphosphate, performing stirring, further adding the filler and ethylene glycol, finally adding the toughening agent and the binder, and stirring the substances evenly. The paint provided by the invention has pollution resistance, high temperature resistance, reflection and other performance, also has the advantages of very good adhesion and scrubbing resistance, high tensile strength and elongation at break, good decorative effect, difficult generation of scars, low construction cost and maintenance cost, use of friendly raw materials, environmental protection and health.

The present invention discloses a preparation method of high substituting degree hydroxypropyl distarch phosphate. It is made up by using water as medium and using potato starch, propylene epoxide, sodium trimetaphosphate and sodium hydroxide as raw material through the processes of mixing paste, esterification, cross-linking, neutralization, washing, drying, sieving and packaging. Said product is a white powder.

The invention relates to a method used nanometer material to modify rape stalk, twin screw extruding technology to make new type green decorating or packing material which is formed by rape stalk, nanometer silicon dioxide, double amino silane, sodium trimetaphosphate, high density polyethylene, azo bis formamide, French chalk, paraffin, chlorinated polyethylene, and ethylene propylene terpolymer. The modifying and molding for the rape stalk is in the same device and technology. It is detected that the main technical criteria of the decorating material are that bending strength 27.4MPa, elastic modulus in bending 1582MPa; surface cigarette igniting resistance are that no yellow spot, black spot, crack, bubbling; it satisfies our country relative standard, can substitute for parts of plastic and wood products.

The invention provides a preparation method and applications of octenyl succinate distarch phosphate. The preparation method comprises the following steps: using potato starch and sodium trimetaphosphate (STMP) to perform crosslinking reaction, and then adding octenyl succinic anhydride which is diluted with absolute alcohol to perform esterification reaction. The octenyl succinate distarch phosphate prepared by the method has the advantages that the product has high viscosity and stability, excellent free fluidity and hydrophobicity, good emulsion stability and high temperature resistance, has acid resistance, alkali resistance and saline environment resistance and also has high freeze-thaw stability; and the special properties of potato starch can be maintained.

The invention discloses a preparation method for a chitosan fruit and vegetable preservative film. The preparation method comprises the following steps of (1) dissolving chitosan into an acetic acid solution, heating to the temperature of 60-70 DEG C, and stirring until the chitosan is completely dissolved to obtain a solution A, wherein 100-150mL of the acetic acid solution is added into every gram of the chitosan; (2) immersing polyvinyl alcohol into an aqueous solution for 1-2 hours, heating to the temperature of 70-90 DEG C, and stirring until the polyvinyl alcohol is completely dissolved to obtain a solution B, wherein 50-80mL of the aqueous solution is added into every gram of the polyvinyl alcohol; (3) mixing the solution A and the solution B according to a volume ratio of (100-200):1, uniformly stirring, adding sodium trimetaphosphate, performing crosslinking reaction for 10-30min to form a film, and drying the film to obtain the chitosan fruit and vegetable preservative film. The tensile property of the chitosan fruit and vegetable preservative film prepared by the preparation method is greatly improved.

The invention belongs to the technical field of preparation and structural transformation of traditional Chinese medicine polysaccharide and relates to a preparation method of phosphorylated epimedium polysaccharide. The preparation method of the phosphorylated epimedium polysaccharide comprises the following steps: carrying out heating reaction on a phosphorylating reagent (sodium tripolyphosphate-sodium trimetaphosphate), epimedium polysaccharide and sodium sulfate for a period of time under alkaline condition, carrying out phosphorylation molecular modification, and selecting out optimal conditions for phosphorylation modification on the epimedium polysaccharide by carrying out a response surface experiment with content of phosphate radicals of products and reagent ratio, reaction temperature, reaction pH value and reaction time as factors. After the phosphorylated epimedium polysaccharide is prepared, in vitro activity of a modified product is studied, and results show that the phosphorylated epimedium polysaccharide has a certain immunoregulation, antiviral and antioxidant effects.

The invention discloses a slow-crosslinked high-strength jelly profile control water-plugging agent. The slow-crosslinked high-strength jelly profile control water-plugging agent comprises, by mass, 0.3% to 0.6% of a hydrophobic associating polymer, 0. 3% to 0.6% of a melamine resin crosslinking agent, 0.03% to 0.05% of a phenol crosslinking agent, 0.2% to 0.4% of an oxygen scavenger, 0.1% to 0.3% of a delayed crosslinking agent, 0.1% to 0.2% of a water loss inhibitor and the balance water. The phenol crosslinking agent comprises one or two of resorcinol and hydroquinone. The oxygen scavenger comprises one or more of thiourea, sodium sulfite and sodium bisulfate. The delayed crosslinking agent comprises one or two of ammonium chloride and sodium trimetaphosphate. The water loss inhibitor comprises one or two of sodium malonate and sodium salicylate. The gelatinization time of the jelly provided by the invention is adjustable and is 6 days or more. After gelatinization, the jelly strength at least reach to level H based on visual inspection. The water-plugging agent has excellent thermal stability, does not lose water after hot treatment at a temperature of 60-90 DEG C for 270 days and can satisfy the requirements on most of deep oil reservoir displacement.

The invention relates to a method for improving viscosity thermal stability of acetic ester starch slurry, in particular to a method for improving viscosity thermal stability of starch slurry during the chemical processing and denaturation of cassava starch. The method comprises oxidization denaturation, esterification denaturation and cross-linking denaturation. After the oxidization denaturation and the esterification denaturation, sodium trimetaphosphate which accounts for 1 percent of the weight of the cassava starch is added, then the reaction lasts 5 hours at the room temperature, and during the reaction, sodium hydroxide solution with the concentration of 3 percent is used for remaining the pH value of the cassava starch slurry to be 9.0-9.2. The invention has the advantages that when the acetic ester starch slurry prepared according to the method of the invention is used, in comparison with the acetic ester starch slurry prepared through oxidization-esterification denaturation, the viscosity thermal stability is improved from 55.6 percent to 81 percent, the stability of sizing quality can be ensured, and the spinning production efficiency and the product quality can be improved.

The invention provides high branch cationic starch for a papermaking wet end and a preparation method thereof. The high branch cationic starch comprises the following raw materials in parts by weight: 30-60 parts of arrow root starch and 40-70 parts of water, and is prepared through a cationic etherification step, a cross-linking reaction step and a drying step. The high branch cationic starch isadded into paper to improve the paper force strength of the paper or to maintain the paper force strength under the condition of improving the primary retention rate and the ash content of the paper.The preparation method provided by the invention benefits the control of the influence of cross-linking degree for starch molecular weight in the synthesis technology of the high branch cationic starch, and the diminishment of the increased scope of the cross-linking degree so as to improve the starch molecular weight to the most extent. The result of combinedly using phosphorus oxychloride, sodium trimetaphosphate and epoxy chloropropane as a cross-linking agent is better than the result of singly using the phosphorus oxychloride as the cross-linking agent. The high branch cationic starch isapplicable to papermaking enterprises which produce cultural paper and are equipped with continuous digesters.

The invention provides compound micro-porous cross-linked starch styptic powder which is prepared by emulsification and cross-linking of one of purified water, potato starch, sodium alginate and sodium carboxymethyl cellulose, an emulsifying agent, a cross-linking agent and a dispersing agent as raw materials, wherein the emulsifying agent is selected from Span and Tween; the cross-linking agent is selected from glutaric dialdehyde, sodium trimetaphosphate, formaldehyde and epoxy chloropropane; and the dispersing agent is selected from paraffin and vegetable oil. The compound micro-porous cross-linked starch styptic powder has the following technical effects: micro-porous starch styptic materials are spherical particles extracted from plant starch and subjected to micro-porous treatment; when micro-porous polysaccharide styptic particles are put on a bleeding wound, the molecules of the particles absorb moisture in blood, and visible components in the blood are aggregated on the surfaces of the particles so as to form a gelatinous mixture, thereby achieving the effect of stopping bleeding in time; and meanwhile, activation of endogenous blood coagulation factors is accelerated, the blood coagulation time is shortened, a local clot is formed, and the styptic effect is finished within tens of seconds.

The invention discloses phosphoric acid esterification snakegourd peel polysaccharide and a medical application thereof. The phosphoric acid esterification snakegourd peel polysaccharide is characterized by being prepared by performing phosphoric acid esterification modification on snakegourd peel polysaccharide by using sodium tripolyphosphate and sodium trimetaphosphate. The phosphoric acid esterification snakegourd peel polysaccharide disclosed by the invention has a significant anti-ageing function, does not have toxic or side effects, cannot cause damages to internal organs, and can be used for preparing anti-ageing medicaments.

The invention discloses an edible lollipop packaging film and relates to the technical field of packaging materials. The edible lollipop packaging film is prepared from raw materials in parts by weight as follows: 90-100 parts of plant starch, 25-30 parts of microcrystalline cellulose, 15-20 parts of cyclodextrin, 15-20 parts of dried skim milk, 13-16 parts of fish bone meal, 10-15 parts of silk fibroin protein, 10-15 parts of Chinese herb extracts, 8-12 parts of fenugreek gum, 8-12 parts of mannitol, 6-10 parts of carnosol, 6-10 parts of potassium sorbate, 5-8 parts of sodium trimetaphosphate, 12-15 parts of palm oil, 35-40 parts of ethanol and 200-300 parts of water. The prepared packaging film is non-toxic and harmless and can be eaten together with a lollipop, the added Chinese herb extracts have the functions of invigorating stomach, helping digestion, resisting oxidation and preventing corrosion, the edible value is improved, and the guarantee period of the lollipop is prolonged.

The invention provides a method for preparing an absorbable and antibacterial guided tissue regeneration membrane for a bone-like structure, and belongs to the field of biological medical materials. The method comprises the following steps: firstly, preparing a cell free bovine pericardial collagen fiber membrane by adopting a repeated freeze-thaw method and a surface active agent TritonX-100, or preparing a demineralized cell free collagen fiber membrane of a cattle lamellar bone by using a method of EDTA decalcification by using the surfactant TritonX-100; treating by using sodium trimetaphosphate to obtain a phosphorylated collagen fiber membrane; with the assistance of a direct-current electric field, mineralizing in agar hydrogel containing calcium and phosphate, thereby obtaining a mineralized collagen membrane with a bone-like structure with certain hardness; and finally soaking the mineralized collagen membrane into a minocyline solution, and preparing an antibacterial bone-like structured composite membrane structure by virtue of the characteristics of combined minocyline and hydroxyapatite. The guided tissue regeneration membrane provided by the invention has a bone-like structure, is capable of maintaining a bone defect space, is good in operation forming property and antibacterial property, and can be applied to clinical practice for bone defect remediation and reconstruction in periodontal departments, dental implant mediation and occlusalf surfaces.

The invention provides a lightweight composite gypsum board including a foamed low density set gypsum core, a top non-foamed (or reduced foamed) bonding high density layer and a bottom non-foamed (or reduced-foamed) bonding high density layer, a top cover sheet bonded to the foamed low density set gypsum core by the top non-foamed (or reduced-foamed) bonding high density layer, and a bottom cover sheet bonded to the foamed low density set gypsum core by the bottom non-foamed (or reduced-foamed) bonding high density layer. The foamed gypsum core and the non-foamed (or reduced-foamed) bonding layers are made from a gypsum slurry including stucco, pregelatinized starch, and preferably a naphthalenesulfonate dispersant and sodium trimetaphosphate. The foamed gypsum core has a density of less than about 30 pcf using soap foam in the gypsum-containing slurry. The gypsum board is lightweight with high strength. A method of making the gypsum board is also provided.

The invention relates to an absorbable starch bleeding-stopping powder and preparation method thereof. The method comprises: taking plant native starch and carboxy methyl starch as raw materials, performing emulsion dispersing under the effects of span 80, tween 80 and plant oil at pH of 9-10 at a temperature of 45-70 DEG C, crosslinking with sodium trimetaphosphate, extracting with ethyl acetate and performing liquid separation, washing with anhydrous ethanol, drying in a baking oven, and sterilizing, so as to obtain the absorbable starch bleeding-stopping powder. The bleeding-stopping powder has good biocompatibility, is directly applicable to general bleeding, deep bleeding and bleeding at positions where operations are difficult to reach, and is simple and convenient to use. The bleeding-stopping power employs starch as the raw material, is nontoxic, free of stimulation, wide in source, low in cost and simple and feasible in technology, and has wide clinic application prospect.

The invention discloses a method for preparing L-ascorbic acid-2-phosphate. The preparation method comprises the following steps: taking VC raw powder, sodium trimetaphosphate, calcium chloride and calcium hydroxide as raw materials to perform catalytic esterification reaction; and standing and curing a catalytic esterification product for 18+ / 2 hours, and drying the product to obtain the L-ascorbic acid-2-phosphate. The L-ascorbic acid-2-phosphate has the characteristics of large specific gravity of materials, small water solubility and the like, and is particularly suitable for compound feed of aquatic animals.

The invention provides a modified starch, which comprises the following components by weight: 100 parts of corn starch, 1-4 parts of sodium trimetaphosphate, 0.6-1 part of NaOH, 0.8-1.5 parts of HCl and 130-140 parts of mixing water. The modified starch possesses the advantages of good flowability, certain lipophilicity, high gelatinization temperature, stable viscosity and good anti-shearing ability, and can replace partial polyether glycol and partial isocyanate in the production of polyurethane foamed plastics.

The invention discloses a carboxymethyl-chitosan compound fresh-keeping film and a preparation method thereof, and relates to the technical field of food packaging. The compound fresh-keeping film is prepared by the following raw materials according to mass percentage: 2% to 5% of carboxymethyl chitosan, 1% to 1.4% of glycerinum, 0.5% to 1% of paraffin, 0.5% to 0.8% of sodium trimetaphosphate, 0.1% to 0.5% of food-grade polysorbate-80, 0.05% to .2% of garlic essential oil, 0.15% to 0.3% of sorbic acid, 0.05% to 0.2% of silicon dioxide and 94.85% to 95.40% of distilled water; the preparation method comprises the following steps: firstly, preparing a fresh-keeping solution according to the mass percentages; secondly, coating the fresh-keeping solution on the surface of a film carrier; thirdly, stripping the film from the film carrier when the film is solidified to acquire the carboxymethyl-chitosan compound fresh-keeping film. The carboxymethyl-chitosan compound fresh-keeping film has the characteristics of high transparency, good flexibility, excellent retraction performance, low moisture-permeating rate and the like, so that the quality food can be improved obviously, the shelf life of food can be prolonged obviously, and the economic benefit is increased; besides, the carboxymethyl-chitosan compound fresh-keeping film has excellent biocompatibility with organisms, and the problem of residual toxicity does not exist.

The invention provides cooked adhesive powder for wall rendering and a preparation method thereof. The cooked adhesive powder comprises the following components in parts by weight: 100 parts of starch, 1-3 parts of modifier I, 3-10 parts of modifier II, 20-30 parts of etherifying agent, 15-20 parts of catalyst, 1-5 parts of activator and 26-30 parts of ethanol, wherein the modifier I is one or two of epichlorohydrin, urea, sodium metapohsphate and phosphorus oxychloride; the modifier II is combination of alkenyl succinic anhydride (ASA), polyacrylamide and epoxy resin. The adhesive powder for wall rendering provided by the invention has the characteristics of excellent comprehensive performance, high viscosity, strong film forming property and good water resistance.

The invention belongs to the application field of biological medical material, and particularly relates to a preparation method of a composite hydrogel dressing for repairing a skin injury. The composite hydrogel dressing is a hydrogel dosage form, is flexible and smooth in texture, and has good water absorption and low degradation property. The composite hydrogel dressing is prepared through the following steps of: carrying out chemically cross-linking on hyaluronic acid and collagen type I in an alkaline solution by using sodium trimetaphosphate as a cross-linking agent, washing a cross-linking product through deionized water and soaking, and removing the residual cross-linking agent and alkali. The composite hydrogel dressing can be used for rapidly prompting the injury to cure, and can be applied to repairing various types of skin injuries, such as burn and mechanical injury.