1595 results about "Vinyl alcohol" patented technology

The invention discloses a high-barrier polycrystalline silicon packaging film and a preparation method thereof, and relates to the technical field of packaging materials. The high-barrier polycrystalline silicon packaging film consists of a polyester film carrier and functional slurry, the functional slurry is prepared from the following raw materials in parts by weight: 15 to 25 parts of ethylene-vinyl alcohol copolymer, 10 to 18 parts of polyvinylidene chloride, 5 to 10 parts of modified nano montmorillonite, 8 to 15 parts of modified polylactic acid, 3 to 6 parts of tributyl citrate, 1 to 3 parts of antioxidant 1010, 1 to 3 parts of ultraviolet light absorber UV-531, 0.5 to 1.5 parts of nucleating agent NA-11, 1 to 2 parts of silane coupling agent KH-550 and 3 to 7 parts of modified silicon dioxide aerogel; 2 to 5 parts of vinyl trimethoxy silane, 1 to 3 parts of nano silver and 20 to 30 parts of deionized water. The high-barrier polycrystalline silicon packaging film has excellent barrier performance, and can effectively block oxygen, water vapor and the like. The polycrystalline silicon packaging film is good in mechanical performance, not prone to damage, antibacterial, antioxidant and anti-ultraviolet, the quality guarantee period of polycrystalline silicon can be prolonged, the product quality can be guaranteed, and the polycrystalline silicon packaging film has great application value in the field of polycrystalline silicon packaging.

The invention relates to the technical field of chlorinated polyvinyl chloride plastics, in particular to a PVC corrosion-resistant cable protection pipe and a preparation process thereof. The invention aims to solve the problem that the mechanical property and the corrosion resistance of the existing PVC cable protection pipe cannot be considered at the same time. Chlorinated polyvinyl chloride and polyvinyl chloride are subjected to hot mixing to obtain matrix resin, and the corrosion-resistant additive, the composite flame retardant, the flexibilizer and other additives are added to obtain the cable protection tube. The corrosion-resistant additive is obtained by grafting and modifying nano silicon dioxide with epoxy resin and premixing with an ethylene-vinyl alcohol copolymer; the composite flame retardant comprises core layers of nitrogen series, phosphorus series and inorganic hydroxides and a shell layer of an acrylate polymer, and is obtained through a core-shell reaction; the cable protection pipe is prepared through a multi-step mixing process; by introducing the core-shell structure and the corrosion-resistant auxiliary agent, efficient flame retardance and corrosion resistance are achieved, stress is buffered through the flexible shell layer, and the mechanical property of the material is maintained.

The invention discloses an ethylene-vinyl alcohol copolymer and a preparation process thereof, and relates to the technical field of EVOH. According to the preparation process of the ethylene-vinyl alcohol copolymer, through gradient control of EVA polymerization and alcoholysis process conditions, on one hand, uniform control of heat release in a polymerization stage and an alcoholysis stage can be realized, heat in each stage is fully utilized, and the conversion rate and alcoholysis efficiency in the polymerization process are improved; on the other hand, effective regulation and control of EVOH composition, molecular weight distribution, molecular chain sequence structure and stereoregularity can be realized; finally, side reactions in the polymerization stage and the alcoholysis stage can be reduced, and generation of gel and impurities is reduced.

The invention discloses a corrosion-resistant protective sleeve for an aluminum alloy cable and a preparation method of the corrosion-resistant protective sleeve, and belongs to the field of cable protective sleeves. The corrosion-resistant protective sleeve for the aluminum alloy cable is prepared from the following raw materials in parts by mass: 40 to 50 parts of ethylene propylene diene monomer, 15 to 25 parts of fluorinated silicone rubber, 5 to 10 parts of modified thiolated ethylene-vinyl alcohol copolymer, 8 to 15 parts of metal fluoride nanocrystal, 4 to 8 parts of vulcanizing agent, 3 to 8 parts of plasticizer and 3 to 5 parts of flame retardant. The two rubber matrixes are compounded to form a physical barrier layer to prevent corrosion media and water molecules from permeating, material pores can be filled with the metal fluoride nanocrystals, diffusion channels of the corrosion media are reduced, and hydrophobicity and corrosion resistance are improved through cooperation of the metal fluoride nanocrystals and the fluorinated silicone rubber. The modified thiolated ethylene-vinyl alcohol copolymer can improve the compatibility between rubber matrixes and form coordination with metal ions of the metal fluoride nanocrystals, so that the diffusion path of a corrosive medium is prolonged, and the corrosion of the corrosive medium is synergistically blocked.

The invention relates to the technical field of pharmaceutical preparations, and provides a minoxidil film coating agent as well as a preparation method and application thereof. The minoxidil film coating agent provided by the invention comprises 40-60% of propylene glycol, 3-7% of polyvinyl alcohol, 20-30% of ethanol, 1-7% of minoxidil and the balance of water. According to the invention, propylene glycol is taken as a solvent, a plasticizer and a transdermal absorption enhancer, polyvinyl alcohol is taken as a film-forming material, and ethanol is taken as a volatile agent, after administration, ethanol is volatilized to promote film formation of polyvinyl alcohol, and propylene glycol enhances the plasticity of the formed film, so that the effect of reducing liquid medicine loss is achieved, the local medicine concentration is increased, and the bioavailability is improved. The minoxidil liniment disclosed by the invention has excellent skin permeability, can effectively convey a medicine to a required part, and can ensure that the medicine is released at a fixed position of the skin and is accurately administered in a medicine release process, so that the stimulation of liquid medicine flow to other parts is reduced, and a good treatment effect is achieved.

The application discloses a kind of imitated plant leaf hydrogel composite material and preparation method thereof, belong to bionic composite material field.The application first by colorant compounding preparation printing paste, and fabric is printed, obtain the green fabric that can realize to plant leaf " green peak " and " red edge " spectral characteristic simulation, and with green fabric simulation leaf structure in fence organization and skeleton;Then with biomaterial polyvinyl alcohol (PVA) as base material, join with strong hygroscopic monomer and crosslinking agent, initiator blend preparation hydrogel prepolymer solution;Finally, hydrogel prepolymer solution is poured into the mold containing green fabric and copolymerization, it directly forms hydrogel in fabric surface and pore interior, obtains imitated plant leaf hydrogel composite material.The material gets rid of the dependence on hygroscopic salt, has water absorption and simulation effect stable, durability is good and the like advantages.

The invention relates to the technical field of water pollutant removal, in particular to a UiO-66 / sodium carboxymethyl cellulose / polyvinyl alcohol / melamine sponge composite material and a preparation method and application thereof.The preparation method comprises the steps that zirconium chloride and terephthalic acid are dissolved in an organic solvent to obtain a mixed solution, the mixed solution is transferred into a reaction kettle, and through solvothermal reaction, the UiO-66 / sodium carboxymethyl cellulose / polyvinyl alcohol / melamine sponge composite material is obtained; the preparation method comprises the following steps: preparing UiO-66 powder; putting UiO-66 powder into the sodium carboxymethyl cellulose solution, and uniformly stirring the UiO-66 powder and the sodium carboxymethyl cellulose solution to obtain a UiO-66 / CMC mixed solution; placing the UiO-66 / CMC mixed solution in a polyvinyl alcohol solution, and uniformly stirring the UiO-66 / CMC / PVA mixed solution to obtain a UiO-66 / CMC / PVA mixed solution; the preparation method comprises the following steps: dipping a melamine sponge in a UiO-66 / CMC / PVA mixed solution to obtain an adsorption saturated melamine sponge; the UiO-66 / CMC / PVA / coated MS composite material is obtained by repeatedly freezing and thawing the adsorption saturated melamine sponge for multiple times and then freeze-drying, the composite material can be used for rapidly, efficiently and selectively removing phosphate or fluorine ions and the like in water and is convenient to separate and recycle, and a new thought is provided for development of efficient water treatment adsorbent materials.

A polyvinyl alcohol-cellulose nanocrystal composite hydrogel interface evaporator, and a preparation method therefor and the use thereof. The preparation method for the composite hydrogel interface evaporator comprises the following steps: adding a cellulose nanomicrocrystal, polyvinyl alcohol and an acid liquor to water, mixing same, and heating the mixture to dissolve the polyvinyl alcohol, so as to obtain a hydrogel precursor solution; and adding reduced graphene oxide and a cross-linking agent to the hydrogel precursor solution, uniformly mixing same to obtain a mixed solution, gelatinizing the mixed solution, and then freeze-drying same, so as to obtain a target product. The preparation method is simple to operate, low in terms of cost, and environmentally friendly, and endows the hydrogel with excellent multifunctional properties, including wide spectrum absorption performance, seawater desalination performance, wastewater purification performance, etc.

Provided in the present invention are a polyvinyl alcohol powder and hydrogel, and a preparation method therefor and the use thereof. The method mainly comprises: preparing a polyvinyl alcohol powder from polyvinyl alcohol, then mixing same with water and swirling same to make the powder swell into discrete microgel particles, and applying pressure to make polyvinyl alcohol molecular chains at the interface of the microgel diffuse, entangle and link with each other and crystallize and fuse, so as to prepare a polyvinyl alcohol hydrogel. With regard to the polyvinyl alcohol powder, the preparation method therefor comprises direct pulverization, or physical crosslinking prior to pulverization, or casting into a film prior to pulverization, etc.; and preferably, the powder is prepared by first performing casting into a film and then pulverizing same, which can make the powder more uniform in terms of crystallinity and more stable in terms of performance. With regard to the swelling process of the polyvinyl alcohol powder, it is necessary to strictly control the ratio of the powder to water, the temperature and the time to ensure that before swelling is complete, transferral into a mold is conducted and pressure is applied to form a hydrogel. Products meeting different performance requirements, including prostheses for the soft tissues of various locomotor systems, medical and esthetic filling materials, etc., are prepared by adjusting process parameters; and the polyvinyl alcohol powder can also be used for preparing PVA plastics having a three-dimensional structure, and thus has broad application prospects.

This invention discloses a one-piece molded all-plastic flexible hose sheet and its composite hose, belonging to the field of polymer material technology. The one-piece molded all-plastic flexible hose sheet of this invention has a three-layer structure: an outer PE film, an intermediate layer, and an inner PE film. The intermediate layer is selected from one of the following: an intermediate polymer layer, a three-layer composite layer formed by an intermediate polymer layer, a polyethylene layer, and an intermediate polymer layer, or a three-layer composite layer formed by an intermediate polymer layer, an ethylene-vinyl alcohol copolymer layer, and an intermediate polymer layer; the intermediate layer may have a double-sided coated or uncoated adhesive layer; the intermediate polymer layer is polymerized from 2,6-dihydroxyisophthalic acid, diaminoalkane, and 4,4'-tetraphenylsilane. The all-plastic flexible hose sheet provided by this invention is formed in one piece using a five-layer co-extrusion machine, possessing excellent gas barrier properties, water vapor barrier properties, high mechanical strength, and good interlayer peel strength.

The invention discloses a high-barrier polyethylene film and a preparation method thereof, and relates to the technical field of high polymer materials. The invention discloses a high-barrier polyethylene film. The high-density polyethylene composite material is prepared from the following raw materials in parts by weight: 25 to 40 parts of high-density polyethylene, 15 to 30 parts of linear low-density polyethylene, 8 to 16 parts of ethylene-vinyl alcohol copolymer, 3 to 8 parts of nano montmorillonite, 5 to 10 parts of modified layered double hydroxide, 2 to 6 parts of nano silicon dioxide aerogel, 0.2 to 0.6 part of antioxidant 1076, 0.1 to 0.4 part of light stabilizer UV-770, 3 to 7 parts of tributyl citrate and 1 to 3 parts of octadecanamide. 1-3 parts of polyethylene wax, 0.6-1.2 parts of a silane coupling agent KH560 and 7-12 parts of a functional additive. According to the high-barrier polyethylene film disclosed by the invention, by using the modified layered double hydroxide and the functional additive, the barrier property and the antibacterial property are enhanced, the mechanical property is improved, the comprehensive performance is excellent, and the application prospect is good.

The invention discloses a recoverable high-barrier-property multilayer composite film and a preparation method thereof. The composite film adopts a five-layer symmetrical structure, namely a heat sealing layer, a first bonding layer, a blocking layer, a second bonding layer and a surface protection layer. Wherein the barrier layer is a montmorillonite modified ethylene-vinyl alcohol copolymer, and montmorillonite is modified by a carboxyl functionalized ammonium bromide intercalator; the bonding layer is maleic anhydride grafted polylactic acid; the heat sealing layer contains modified composite filler; the surface protection layer is a polyethylene / graphene modified coupling agent composite system. The preparation method comprises the steps of intercalation modified montmorillonite preparation, barrier layer material melt blending, five-layer co-extrusion casting, gradient hot pressing and curing treatment. The problems that a traditional high-barrier film is unrecyclable, the interlayer binding force is weak and the high-temperature stability is poor are solved, the ultrahigh barrier performance that the oxygen transmission rate is smaller than or equal to 0.5 cm < 3 > / (m < 2 >. 24 h) and the water vapor transmission rate is smaller than or equal to 1.0 g / (m < 2 >. 24 h) is achieved, and the mechanical property retention rate is larger than or equal to 85% after recycling and re-pelletizing.

The invention relates to the technical field of fire extinguishing microcapsules, in particular to a high-airtightness perfluorohexanone fire extinguishing microcapsule and a preparation method and application thereof.The perfluorohexanone fire extinguishing microcapsule comprises a composite shell layer and a fire extinguishing core, and the composite shell layer is made of ethylene-vinyl alcohol copolymer resin and silicon dioxide nanoparticles; the fire extinguishing core is a perfluorohexanone fire extinguishing agent and is applied to preparation of indoor fire extinguishing pastes, fireproof coatings and polyurethane adhesive materials. According to the perfluorohexanone fire extinguishing microcapsule disclosed by the invention, the diffusion of low-polarity perfluorohexanone is effectively prevented by utilizing the strong hydrogen-bond interaction between hydroxyl groups in the ethylene-vinyl alcohol copolymer resin, and especially under the condition of relatively high temperature, the perfluorohexanone fire extinguishing microcapsule has a good fire extinguishing effect. The problem that an existing perfluorohexanone fire extinguishing microcapsule is poor in long-term air tightness under the condition of high encapsulation efficiency is effectively solved, and meanwhile harmful substances such as formaldehyde cannot be generated.

The invention relates to the technical field of packaging materials, and discloses a high-barrier multilayer co-extrusion composite film which sequentially comprises an inner layer, a first bonding layer, a first barrier layer, a second bonding layer, a second barrier layer, a third bonding layer and an outer layer from bottom to top. And the second barrier layer is a nano silicon dioxide modified polyvinyl alcohol layer. The two different barrier layers are arranged, the first barrier layer has a good barrier effect on gas, the second barrier layer has outstanding barrier performance on water vapor, and the two barrier layers have a synergistic effect, so that the comprehensive barrier performance of the composite film on oxygen, water vapor, peculiar smell and the like is remarkably improved, the shelf life of a packaged product can be effectively prolonged, and the packaging cost is reduced. According to the high-barrier film, the high-barrier property is ensured, the quality and the performance of a product are ensured, and the use of expensive materials and a complex production process is avoided and the production cost is reduced by reasonably selecting each layer of material and optimizing the structural design on the premise of ensuring the high-barrier property.

The invention relates to the field of polyurethane, and particularly discloses high-barrier water-based polyurethane for packaging. The preparation raw materials of the high-barrier water-based polyurethane for packaging comprise polymeric polyol, isocyanate, a modified composite filler, an ethylene-vinyl alcohol copolymer, maleic anhydride grafted polyethylene, a hydrophilic chain extender, a post-chain extender and water. Wherein aminosilane, polyethylene glycol and carbonyl diimidazole are adopted to carry out synergistic modification on the graphene oxide nanosheets and the glass powder, so that the graphene oxide nanosheets are well dispersed in a polyurethane matrix in a two-dimensional continuous layered structure, and the diffusion path of oxygen, water vapor and other gas molecules in the polyurethane matrix is remarkably prolonged; and the glass powder can fill gaps among graphene oxide nanosheet layers, so that the compactness of the composite material is further enhanced, the permeation of water vapor is reduced, and the barrier property is improved.

The application discloses a high-temperature-resistant and high-barrier composite film and a preparation method thereof, and relates to the technical field of layered products, which comprises A, B and C layers in sequence; the A layer comprises a temperature-resistant layer, a substrate layer and a barrier layer in sequence; the B layer comprises a substrate layer, a connecting layer, a barrier layer, an aluminum plating layer and a protective layer in sequence; the C layer is a heat-sealing layer; the preparation raw materials of the temperature-resistant layer material comprise aluminum oxide and titanium nitride; the preparation raw materials of the barrier layer material comprise ethylene-vinyl alcohol copolymer, succinamic acid, furoinic acid and carbon nanotubes; and the preparation raw materials of the heat-sealing layer material comprise titanium carbide, high-density polyethylene, metallocene polyethylene and zinc stearate. The high-temperature-resistant and high-barrier composite film provided by the application has excellent high-temperature resistance and barrier properties.

The invention relates to the field of packaging materials, in particular to a high-temperature-resistant water-soluble polyvinyl alcohol packaging film as well as a preparation method and application thereof. The high-temperature-resistant water-soluble polyvinyl alcohol packaging film is prepared from the following raw materials: polyvinyl alcohol, modified polyvinyl alcohol, a compound composition, modified nanoparticles, a surfactant, deionized water and the like. The finally prepared film material not only has good mechanical properties, but also can maintain good water solubility, barrier property and other properties while having excellent high temperature resistance, solves the contradictory problem that the high temperature resistance of the existing PVA film is changed by sacrificing other properties, avoids the complex process of multi-layer co-extrusion film formation, and is suitable for large-scale production. And the equipment cost is further saved, the comprehensive performance requirements of the existing packaging field on the PVA film are met, and the method has very excellent application prospects.

The invention belongs to the field of functional textile materials, and provides a one-way moisture-conducting breathable fabric based on a vinyl elastomer and a preparation method of the one-way moisture-conducting breathable fabric based on the vinyl elastomer. The hydrophilic coating contains a vinyl elastomer matrix, polyvinyl alcohol, a zwitterionic polymer and a cross-linking agent, the hydrophobic coating contains a vinyl elastomer matrix, vinyl-terminated polydimethylsiloxane, polyhedral oligomeric silsesquioxane and other components, the coatings are only attached to the surfaces of yarn fibers and do not block pores, and a wettability gradient structure is formed; the excellent performance that the static contact angle gradient in the thickness direction is larger than or equal to 50 degrees, the capillary water absorption height from the inner side to the outer side is larger than or equal to 3.0 cm / 10 min, the capillary water absorption height from the outer side to the inner side is smaller than or equal to 1.0 cm / 10 min, the moisture permeation amount is larger than or equal to 5000 g.m.24 h, and the air permeability after curing is 65% or above of a fabric base material is achieved, the technical problem that an existing fabric is insufficient in moisture conductivity and air permeability is solved, and wide application value is achieved.

A method for preparing monodisperse nanoscale calcium fluoride, comprising the following steps: (S1) dispersing calcium long-chain alkylbenzenesulfonate and an acrylate copolymer in a mixed solution of water, n-hexane, and an alcohol to form a stable emulsion A, wherein monomers of the acrylate copolymer comprise (meth)acrylic acid, a polyether macromonomer, and a C1-4 alkyl (meth)acrylate; (S2) dissolving a fluoride salt in water, adding polyvinyl alcohol, and uniformly mixing these materials to obtain a solution B; and (S3) slowly dropwise adding the solution B to the emulsion A under stirring and ultrasonic conditions, and carrying out standing for aging, centrifugal separation, washing, and drying to obtain monodisperse nanoscale calcium fluoride. By using the calcium long-chain alkylbenzenesulfonate with surface activity as a calcium source in combination with homemade acrylate as a dispersing agent, an emulsion is formed in a specific combined solvent, and by dropwise adding a fluorine salt aqueous solution to the emulsion under an ultrasonic condition, nanoscale calcium fluoride with a uniform and controllable particle size can be prepared under the action of a microemulsion.

The invention belongs to the technical field of water treatment materials, and particularly discloses chitosan-polyvinyl alcohol photo-thermal aerogel as well as a preparation method and application thereof. Chitosan, polyvinyl alcohol and genipin are cross-linked to prepare the chitosan-polyvinyl alcohol photo-thermal aerogel, and the chitosan-polyvinyl alcohol photo-thermal aerogel has the advantages of being simple in preparation method, low in cost, low in energy consumption, high in light absorption rate, high in evaporation rate, good in salt resistance and stability, capable of self-floating and the like; meanwhile, the hydrophilic advantages of the chitosan and the polyvinyl alcohol are combined, the hydrophilic performance is remarkably enhanced, the efficient evaporation performance is shown, the purpose of efficient evaporation can be achieved, and the chitosan / polyvinyl alcohol composite material has huge potential application prospects in the fields of seawater desalination, sewage treatment and the like.

The invention discloses a multi-component composite material for removing heavy metal cadmium in a water environment as well as a preparation method and an application method of the multi-component composite material. The multi-component composite material is mercaptan modified charcoal-sodium alginate / polyvinyl alcohol composite gel balls; the preparation method comprises the following steps: preparing a turbid liquid composed of a polyvinyl alcohol solution, sodium alginate and mercaptan modified biochar; the cross-linking reaction product of the turbid liquid is the composite gel ball; the multi-component composite material disclosed by the invention is high and stable in removal efficiency of cadmium in water or sediments, and the maximum adsorption capacity can reach 162.45 mg / g; and after a regeneration cycle test, the Cd < 2 + > adsorption capacity can still reach 70% or above of the initial adsorption capacity, so that the Cd < 2 + > adsorbent has good recycling performance and excellent cycle performance.

The invention discloses a polypropylene composite material as well as a preparation method and application thereof, and belongs to the technical field of high polymer materials. The polypropylene composite material is prepared from the following components in parts by weight: 44 to 60 parts of polypropylene resin, 5 to 15 parts of ethylene-vinyl alcohol copolymer, 10 to 25 parts of modified talcum powder and 15 to 25 parts of toughening agent. The polypropylene resin, the ethylene-vinyl alcohol copolymer, the modified talcum powder, the flexibilizer and the antioxidant are compounded, the compatibility of all the components is good, the compounded material has good bonding performance with other plastic materials (such as PMMA), meanwhile, the tensile strength and impact strength of the polypropylene composite material can be effectively improved, and the service life of the polypropylene composite material is prolonged. The requirements of automobile decorative parts on the adhesive property, the rigidity and the toughness can be met.

The invention relates to the technical field of polyethylene packaging films, and particularly discloses an antibacterial polyethylene composite packaging film and a preparation method thereof.The antibacterial polyethylene composite packaging film comprises an inner layer, a middle layer and an outer layer, the inner layer is prepared from the following raw materials in parts by weight: 60 to 80 parts of low-density polyethylene, 25 to 35 parts of polypropylene, 4 to 6 parts of modified filler, 0.3 to 0.6 part of antioxidant and 1 to 3 parts of compatilizer; the middle layer is prepared from 62 to 75 parts of high-density polyethylene, 28 to 40 parts of ethylene-vinyl alcohol copolymer, 0.8 to 1 part of anti-binding agent and 2 to 5 parts of compatilizer; the outer layer comprises 55-70 parts of high-density polyethylene, 35-45 parts of metallocene polyethylene, 12-25 parts of nylon, 4-10 parts of antibacterial modified montmorillonite and 3-6 parts of compatilizer, the polyethylene composite packaging film has good processability and good stability, the composite film adopts a double-layer antibacterial design of the inner layer and the outer layer, the middle layer has excellent barrier property and good compactness, and the polyethylene composite packaging film is suitable for being used as a packaging film. The composite packaging film has excellent antibacterial performance and mechanical performance and good comprehensive performance.

The invention provides a leveling composition and a preparation method and application thereof, the leveling composition comprises negatively charged nanoparticles, an oxidant, a catalyst, a stabilizer, a lubricant and a solvent, the pH value of the leveling composition is less than or equal to 4, and the lubricant comprises one or more of polyethylene glycol and polyvinyl alcohol. In the application, in a proper pH environment, through matching of the components, metal tungsten can be quickly softened and removed, and under the combined action of a protective layer formed by the lubricant and electrostatic repulsion of negatively charged nanoparticles and oxides, the oxide is low in leveling speed and small in scratch number, so that the leveling speed selection ratio of the metal tungsten to the oxide is increased, and the leveling effect of the metal tungsten is improved. And the flattening effect is improved, so that the production yield of the semiconductor device is improved, and the comprehensive performance of the semiconductor device is improved.

The invention discloses a low-shrinkage acrylate gel material and a preparation method thereof. The gel material is prepared by mixing a solution A and a solution B according to an equal proportion, the liquid A comprises acrylate, a cross-linking agent, an accelerant and a retarder; the acrylate is a calcium acrylate solution, a magnesium acrylate solution or a mixed solution of calcium acrylate and magnesium acrylate; the concentration of the acrylate in the solution A is 15wt.%-35wt.%; the liquid A is also added with a modified material, and the modified material is selected from at least one of hydroxyethyl ester, chloroprene rubber, polyurethane, polyvinyl alcohol and epoxy resin; the addition amount of the modified material is 1%-5% of the total mass of the solution A; the solution B comprises an initiator and distilled water; the initiator is selected from at least one of ammonium persulfate, hydrogen peroxide and azodiisobutyronitrile; the use amount of distilled water in the solution B is determined according to initiator concentration; by optimizing an acrylate compound system, introducing an anti-shrinkage functional component and accurately controlling a preparation process, the comprehensive improvement of material performance and engineering applicability is finally realized.

To provide a composition for external use on the skin for reducing skin wrinkles containing polyvinyl alcohol, and more particularly, a composition excellent in reducing skin wrinkles by sustainably contracting the skin only by drying after application to the skin without a separate film, by containing a high molecular weight polyvinyl alcohol.SOLUTION: The composition according to the present disclosure can reduce skin wrinkles without side effects and at a lower cost compared to conventional wrinkle-improving treatments.SELECTED DRAWING: Figure 1

The invention relates to a preparation method of quartz sand, and belongs to the technical field of quartz. The preparation method comprises the following steps: S1, adding a polyvinyl butyral solution into silica sol, and uniformly stirring to obtain silica sol dispersion liquid; the polyvinyl butyral solution comprises polyvinyl butyral (PVB) and tert-butyl alcohol; s2, performing spray drying on the silica sol dispersion liquid to obtain quartz microspheres; and S3, carrying out oxidation carbon removal treatment and vacuum dehydroxylation treatment on the quartz microspheres to obtain the quartz sand. Drying cracking and micro-hollow structure defects of the quartz sand can be effectively eliminated, it is ensured that the product is compact and free of pores, and the structural integrity and the use reliability are greatly improved; the density performance bottleneck of quartz sand is successfully broken through, and the bulk density after sintering is remarkably improved; the particle size distribution of the quartz sand can be accurately controlled, and the product particle size uniformity is ensured.

The invention discloses a metal powder metallurgy forming process, and belongs to the technical field of metal powder metallurgy. The process comprises the following steps: preparing a metal mixture containing tungsten, copper, nickel, iron and an interface toughening agent according to a specific proportion, adding a polyvinyl alcohol aqueous solution, and uniformly stirring; carrying out compression molding on the mixture to obtain a green body; performing high-temperature sintering steps such as pre-sintering, sintering and cooling to obtain a sintered blank; and finally shaping to obtain a finished product. Compared with the prior art, the fracture toughness and elongation performance of the material are remarkably improved, innovative breakthrough is brought to a metal powder metallurgy forming process, and the method can be widely applied to the fields of aerospace, automobile manufacturing and the like to meet the requirements for high-performance metal parts.

The invention provides a tin-based perovskite thin film, a preparation method thereof and a tin-based perovskite solar cell, and belongs to the technical field of photovoltaic materials. The preparation method comprises the following steps: dissolving a tin-based perovskite raw material in an organic solvent, and adding polyvinyl alcohol or polyvinylpyrrolidone to prepare a tin-based perovskite precursor solution; and coating the tin-based perovskite precursor solution through a printing method to form a film, and carrying out annealing treatment to obtain the tin-based perovskite thin film. According to the invention, polyvinyl alcohol or polyvinylpyrrolidone is used to slow down the crystallization rate of perovskite, and is used as a template to provide heterogeneous nucleation sites, so that the defect state density is reduced, and the compactness of the perovskite film is improved.

The invention relates to a high-strength self-cleaning infrared radiation heat dissipation water-based coating as well as a preparation method and application thereof. The coating comprises the following components in parts by weight: 40-55 parts of water, 5-10 parts of a water-based binder, not more than 20 parts of a high-emissivity filler and not more than 5 parts of a fluorocarbon surfactant, the water-based binder is selected from at least one of styrene-acrylic emulsion, water-based polyurethane, polyvinyl alcohol, water-based acrylic resin, water-based epoxy resin and water-based alkyd resin, and the fluorocarbon surfactant is selected from at least one of water-based acrylic emulsion, water-based polyurethane, polyvinyl alcohol, water-based acrylic resin, water-based epoxy resin and water-based alkyd resin. The high-emissivity filler is selected from at least one of BaSO4, ZnO, Al2O3, SiC, BN (boron nitride) and SiO2, and the fluorocarbon surfactant is selected from at least one of FS-65, FS-34, ST-110, FC-4432 and FS-3100. According to the invention, ZnO, BaSO4 and the like are introduced as composite fillers, so that the coating is endowed with high strength, self-cleaning property and full-wave-band high emissivity, various properties such as wear resistance, adhesion, acid and alkali resistance, organic solvent corrosion resistance, aging resistance, high and low temperature resistance and the like of the coating are improved, and the coating can meet the requirements of various different heat dissipation scenes when being applied to electronic components.