582 results about "Acid resistance" patented technology

The invention discloses a toluidine red pigment for a building coating and a preparation method of the toluidine red pigment, and belongs to the technical field of pigment synthesis, adamantane is introduced into toluidine red, and the adamantane has a stable cage structure, so that the water resistance and acid and alkali resistance of the pigment are improved; in addition, the weather resistance and the thermal stability of the pigment can be improved, so that the durability of the toluidine red pigment for the building coating in an outdoor environment is improved; the cyclodextrin modified resin and the adamantane modified pigment can form a stable host-guest compound through a self-assembly effect, and the dispersity and covering power of the pigment are improved, so that the stability and construction performance of the pigment are improved; good application prospects are realized in the building field.

The invention discloses a preparation method of a breathable underwater self-adhesion myoelectricity sensing fabric. The preparation method comprises the following steps: step 1, preparing a G-PU material with high viscosity; step 2, preparing a high-elasticity breathable RGO coated fabric; step 3, preparing a G-PU / RGO myoelectricity fabric; the invention belongs to the technical field of application of graphene, polyurethane and wet adhesives, according to the method, graphene oxide and viscous waterborne polyurethane are adopted to prepare a water-resistant and acid-resistant RGO / G-PU composite material with excellent adhesive force through a two-step method, a sensing fabric is prepared through a coating process, the preparation process is simple, the production efficiency is high, and the application range is wide. The fabric has the advantages of self-adhesion, water resistance, acid resistance and the like, solves the problems that a common sensing fabric is low in adhesive force and not resistant to water, and particularly relates to a preparation method of a fabric capable of serving as a self-adhesion water-resistant sensing material for sensing human body actions and myoelectricity.

The invention belongs to the technical field of cement concrete surface coatings, and discloses a cement concrete surface coating structure with acid-resistant and corrosion-resistant functions, which has the advantages that the acid resistance is improved: a composite coating structure is adopted, and the advantages of modified epoxy resin, nano filler and polyurea are combined, so that the acid resistance and durability of the coating are remarkably improved. The modified epoxy resin primer has good permeability, so that the adhesive force between the coating and a concrete base layer can be effectively enhanced, and the falling risk is reduced. And compared with a traditional epoxy resin coating, the preparation method of the composite coating simplifies the curing process and reduces the construction difficulty. And the cost is reduced: the nanofiller is adopted to replace part of the polyurea material, so that the cost of the coating is reduced, and the performance is improved. The coating is endowed with excellent hydrophobicity and self-cleaning capability through surface hydrophobic treatment, dirt adhesion is reduced, and the service life is prolonged.

The invention relates to the technical field of dye synthesis, and particularly discloses a 5-substituted amino-5 '-acetamido-3, 3'-dipyridyl derivative as well as a preparation method and application of the 5-substituted amino-5 '-acetamido-3, 3'-dipyridyl derivative. The structure of the 5-substituted amino-5 '-acetamido-3, 3'-dipyridyl derivative is as shown in a formula (I) in the specification, according to the application, N-acetyl blue is used as a parent for modification, and different derivative structures are introduced to amino groups, so that the novel bipyridine dye, namely the 5-substituted amino-5 '-acetamido-3, 3'-bipyridine derivative, is obtained. The 5-substituted amino-5 '-acetamido-3, 3'-dipyridyl derivative has higher color development intensity, and has the advantages of comprehensive color fastness, water washing resistance, acid resistance, sublimation resistance, wet friction resistance, excellent performance and the like when being applied to fabric dyeing.

The invention discloses a method for recovering mixed acid waste liquid containing hydrofluoric acid, which comprises the following steps: reacting raw materials with sodium salt or potassium salt, and filtering to obtain filtrate; the raw material is mixed acid waste liquid containing hydrofluoric acid; feeding the filtrate into a diffusion dialysis device for treatment, wherein the diffusion dialysis device comprises a homogeneous anion exchange membrane; the recovery liquid obtained through treatment of the diffusion dialysis device is fed into a membrane separation device, the membrane material of the membrane separation device is an acid-resistant metal ion removal membrane, and the recovered mixed acid is obtained on the permeation side of the membrane separation device. According to the method, impurities and metal ions in the low-concentration waste acid solution can be effectively removed, the product reaches the electronic-grade recycling standard, the resource recycling rate is increased, the technological process is simple, energy consumption is low, and the method is suitable for industrial application and popularization.

The invention relates to a preparation method of a composite nano sponge for efficiently adsorbing rare earth ions in acidic wastewater, a product and application thereof, and belongs to the technical field of rare earth ion separation and purification. The composite nano sponge is prepared by taking cheap and green beta-cyclodextrin, polyvinyl alcohol, phosphorylated chitosan and citric acid as raw materials, mixing beta-cyclodextrin functionalized polyvinyl alcohol and phosphorylated chitosan and taking citric acid as a cross-linking agent. Experimental results show that the composite nano sponge is good in acid resistance, high in adsorption capacity and good in cyclic regeneration capacity, the removal rate of the composite nano sponge to rare earth ions in simulated acid mine water is higher than 92.9%, and the adsorption rate of the composite nano sponge to competitive ions does not exceed 2.0%. The composite nano sponge shows a potential application prospect in the recovery of rare earth ions in acid wastewater, and is expected to improve the current situation that the acquisition way of rare earth elements is single.

The invention discloses a corrosion-resistant aluminum alloy profile and a preparation method thereof, and belongs to the technical field of aluminum alloy profiles. By optimizing the components of the corrosion-resistant aluminum alloy, the strength of the aluminum alloy profile can be guaranteed, and the corrosion resistance of the aluminum alloy profile is positively influenced. Besides, the corrosion-resistant coating is formed on the surface of the corrosion-resistant aluminum alloy base material in a laser cladding mode, the corrosion resistance of the aluminum alloy profile can be remarkably improved while the application performance of the aluminum alloy profile is guaranteed, and in the corrosion-resistant coating, nickel powder can enhance pitting corrosion resistance and intergranular corrosion resistance, so that the corrosion resistance of the aluminum alloy profile is improved. The adhesive force with an aluminum alloy base material is improved; the boron nitride can improve the acid resistance and wear resistance of the surface of the aluminum alloy profile and block a corrosion channel; the lanthanum oxide and the cerium dioxide have a synergistic effect, so that surface grains can be refined, air holes generated in the cladding process are reduced, the compactness of the coating is improved, the compatibility with an aluminum alloy base material is promoted, and the apparent quality of the aluminum alloy profile is guaranteed.

The invention relates to the technical field of flame-retardant coatings, and discloses a nano-material-containing super-hydrophilic flame-retardant coating and a preparation method thereof, and the nano-material-containing super-hydrophilic flame-retardant coating comprises modified epoxy resin, polyethyleneimine, a defoaming agent, a solvent and water. The modified epoxy resin is grafted and modified by aminated nano silicon dioxide, pyridine groups, amino groups and triphenyl phosphate, the aminated nano silicon dioxide and the triphenyl phosphate can effectively improve the flame retardance, the pyridine groups can play a role in corrosion prevention, the shelf life is prolonged, and the hydrophilic property of the coating is greatly improved through multi-amination. The water-based flame-retardant coating has excellent hydrophilicity, heat resistance, acid resistance, alkali resistance and flame retardance, is suitable for most production and living environments, is simple and convenient in production process, and is convenient to widely popularize.

The invention relates to the technical field of water treatment, in particular to a reverse osmosis membrane and a preparation method thereof. The preparation method of the reverse osmosis membrane comprises the following steps: soaking a base membrane in a water phase solution, taking out the base membrane, drying the surface of the base membrane, coating the base membrane with an oil phase solution, carrying out interfacial polymerization reaction, curing, coating with a modifier solution, and drying to obtain the reverse osmosis membrane, the modifying agent comprises 2, 4, 6-tri (4-aminophenyl)-1, 3, 5-triazine-1, 3, 5-tri (4-methyl phenyl) benzene. The successfully grafted COFs can improve the water permeability of the membrane to a certain extent, and also can improve the pollution resistance, acid resistance and oxidation resistance of the membrane, so that the service life of the membrane is prolonged. According to the invention, different effects of the same type of imino COFs introduced to the reverse osmosis membrane are further compared, so that the excellence of the selected imino COFs is highlighted.

The present invention relates to the field of water treatment technology, and more particularly to a kind of reverse osmosis membrane and preparation method thereof.The preparation method of the reverse osmosis membrane includes:Basement membrane is soaked in aqueous phase solution, after taking out surface drying, oil phase solution is coated on basement membrane and carries out interfacial polymerization reaction, after solidification, coating modifier solution, after drying, obtain reverse osmosis membrane;The modifier includes 2,4,6-tris (4-aminophenyl) ‑1,3,5-triazine ‑1,3,5-tris (4-methylphenyl) benzene.The COFs successfully grafted by the present invention can improve the water permeability of membrane to a certain extent, and can also improve the anti-pollution property, acid resistance and oxidation resistance of membrane, and then improve the service life of membrane.The present invention further compares the different effects that the same type of imino COFs are introduced into reverse osmosis membrane, so as to highlight the excellence of the imino COFs selected by the present invention.

The invention provides an oil-water separation mineralization net film as well as a preparation method and application thereof. The oil-water separation mineralization net film comprises an organic layer crosslinked on a grid substrate, the inorganic layer grows in the organic layer in an in-situ mineralization manner; the organic layer is a polymer layer formed by coating a polymer solution containing a cross-linking agent on the grid substrate for cross-linking; the inorganic layer is an inorganic mineral particle layer which grows on the surface of the organic layer in an in-situ mineralization mode. The mineralized net film for oil-water separation not only has excellent binding capacity with the grid substrate, but also has high chemical stability of acid resistance, alkali resistance and organic solvent resistance and excellent mechanical performance, and can be widely applied to oil-water separation under complex conditions.

The invention relates to the technical field of adhesive tapes, and particularly discloses a UV (ultraviolet) visbreaking anti-acid adhesive tape for thinning flexible glass and a preparation process of the UV visbreaking anti-acid adhesive tape. A UV viscosity-reducing acid-resistant adhesive tape for thinning flexible glass comprises a base material layer, a pressure-sensitive adhesive layer and a release film layer which are stacked in sequence, and the pressure-sensitive adhesive layer is prepared from the following raw materials: 85-120 parts by mass of an acrylate copolymer, 3-5 parts by mass of a cross-linking agent, 1.5-2.5 parts by mass of a photoinitiator, 2-5 parts by mass of an acid-resistant nano filler and 0.2-0.4 part by mass of an amine catalyst; the acrylate copolymer is prepared from the following raw materials in parts by mass: 20-30 parts of an imidazolinyl-containing monomer, 15-25 parts of a large-steric-hindrance alkyl-containing monomer, 45-55 parts of a flexible monomer and 5-10 parts of a carboxyl-containing monomer. The UV visbreaking acid-resistant agent prepared by the invention has relatively good acid resistance and reliable UV visbreaking and high initial bonding balance.

The invention provides a high-performance hydrogen fuel cell sealing silicone rubber material and a preparation method thereof, and belongs to the field of rubber composite materials. The sealing silicone rubber material comprises a component A, a component B and a component C, wherein the component A is 45-50 parts of addition type liquid silicone rubber containing 0.01-0.2 part of a platinum-based catalyst; the component B is prepared from 45 to 50 parts of addition type liquid silicone rubber containing 0.01 to 0.5 part of a polymethylhydrosiloxane cross-linking agent; 15 to 20 parts of vinyl fluorosilicone oil; 5-10 parts of white carbon black; 5-10 parts of an acid-resistant filler; and 1-2 parts of a structure control agent. The preparation method comprises the following steps: firstly, preparing an acid-resistant filler composed of fluorosilane coupling agent modified nanoparticles and polytetrafluoroethylene micropowder; and preparing the sealing silicone rubber material. The silicone rubber composite formula provided by the invention can prevent the silicone rubber from being structured and inhibit the corrosion of an acid solution to a silicone rubber matrix; fluorine atoms are introduced into an addition type liquid silicone rubber matrix, so that the problem of poor acid resistance of sealing silicone rubber is fundamentally solved.

Provided is a glass composition having a high elastic modulus and improved acid resistance and alkali resistance. The glass composition according to the present invention has SiO2, Al2O3, B2O3, CaO, and T-Fe2O3 content ratios of 50 mass% < = SiO2 + Al2O3 < = 66 mass%, 0 mass% < = B2O3 < = 10 mass%, 5 mass% < = CaO < = 30 mass%, and 10 mass% < T-Fe2O3 < = 25 mass%. The mass ratio calculated by Al2O3 / (SiO2 + Al2O3) is 0.05 or more and less than 0.15, and the mass ratio calculated by MgO / (MgO + CaO) is 0.001 or more and 0.20 or less.

The invention belongs to the technical field of coating preparation, and discloses a nanoparticle modified heavy anti-corrosion material as well as a preparation method and application thereof. The nano-particle modified heavy anti-corrosion material comprises the following components in percentage by weight: 60-80% of a component A, 10-25% of a component B and 10-30% of a first solvent, wherein the total percentage is 100%; the component A comprises the following components in percentage by weight: 45%-60% of a resin solution, 0.5%-5% of graphene oxide, 8%-20% of polyaniline nanofibers, 0.5%-5% of carbon nanotubes, 0.6%-40% of a filler, 0.3%-3% of an additive and 8%-12% of a cosolvent, and the total percentage is 100%; the component B comprises the following components in percentage by weight: 40-60% of polyamide and 40-60% of a second solvent, wherein the total percentage is 100%. The nano-particle modified heavy anti-corrosion material prepared by the invention has excellent salt mist resistance, acid resistance, alkali resistance, good adhesive force and impact resistance.

The invention relates to the technical field of high polymer materials and sealing, in particular to a rubber gasket and a preparation method of the rubber gasket. The preparation method comprises the following steps: enhancing by using an ethylene-vinyl alcohol copolymer (EVOH) with the ethylene content of 29-48%, carrying out compatibility by using a styrene-ethylene-butylene-styrene block copolymer grafted maleic anhydride (SEBS-g-MA) with the grafting rate of more than or equal to 10%, carrying out synergistic reinforcement by using carbon black and nanoscale calcium carbonate, and carrying out premixing, hot-pressing vulcanization and acid environment aging treatment. Through EVOH enhancement, SEBS-g-MA compatibility, filler synergistic reinforcement and process optimization, multiple improvements of compatibility, mechanical properties, barrier property and acid resistance are achieved, key defects of a traditional EPDM gasket are overcome, and the EPDM gasket has remarkable technical advantages and practical value in the high-end sealing field (such as fuel cells and tunnel engineering).

The invention relates to normalized high-strength medium-carbon acid-resistant container steel and a preparation method, and belongs to the technical field of steel manufacturing. The acid-resistant container steel comprises the following chemical components in percentage by mass: less than or equal to 0.20% of C, less than or equal to 0.55% of Si, 1.20-1.70% of Mn, less than or equal to 0.025% of P, less than or equal to 0.010% of S, less than or equal to 0.050% of Nb, less than or equal to 0.050% of V, less than or equal to 0.030% of Ti, more than or equal to 0.020% of Al, less than or equal to 0.0060% of Ca and a matrix element Fe. A proper amount of Nb (niobium), V (vanadium) and Ti (titanium) alloy elements are added to replace a traditional Cu (copper) and Ni (nickel) alloy combination, and the alloy component cost is greatly reduced while high strength and acid resistance are guaranteed.

The invention belongs to the technical field of flame-retardant materials, and particularly relates to modified piperazine pyrophosphate, a composite flame retardant and a preparation method and application of the modified piperazine pyrophosphate and the composite flame retardant. The modified piperazine pyrophosphate provided by the invention is obtained by modifying piperazine pyrophosphate with a modifier; the modifier comprises silicon resin. According to the preparation method, the piperazine pyrophosphate is modified by adopting a specific type of silicon resin as a modifier, and the piperazine pyrophosphate is coated by utilizing a three-dimensional network structure of the silicon resin, so that the hydrophobicity and the flowability of the piperazine pyrophosphate powder can be improved, and the piperazine pyrophosphate powder has good dispersity in a high polymer material; and the paint has good flame retardance, water resistance, acid resistance and alkali resistance.

According to the high-flux chlorine-resistant and acid-alkali-resistant reverse osmosis composite membrane and the preparation method thereof, a porous supporting layer is sequentially immersed into a first water-phase solution, an organic-phase solution, a second water-phase solution and a third water-phase solution, ester bonds are formed through esterification reaction of water-soluble monomers, chlorine attack sites do not exist on the ester bonds, the chlorine resistance can be effectively improved, and the reverse osmosis composite membrane can be used for preparing the high-flux chlorine-resistant and acid-alkali-resistant reverse osmosis composite membrane. The reverse osmosis membrane with high flux and high desalination rate is obtained; the composite membrane is subjected to surface grafting modification, and the reverse osmosis active layer is covered with the protective layer, so that the chlorine resistance, acid resistance and alkali resistance of the membrane are greatly improved, and the service life of the membrane is prolonged; the preparation method has the characteristics of simplicity, convenience in operation, cheap and easily available raw materials, large-scale industrial production and the like, and can be widely applied to brackish water treatment and seawater desalination.

The invention relates to conductive silver paste and a preparation method and application thereof, and belongs to the technical field of conductive paste. The conductive silver paste provided by the invention comprises the following components in parts by weight: 55-64 parts of inorganic silver powder, 5-15 parts of a silver compound, 5-9 parts of glass powder, 10-34 parts of an organic carrier and 1-5 parts of an additive, the glass powder comprises SiO2 and B2O3, and the ratio of the mass of the silver compound to the total mass of SiO2 and B2O3 in the glass powder is 1: (0.1-1). Specific components are added into the conductive silver paste, the content of the components and the content of functional groups are adjusted, it is guaranteed that the paste has good conductivity, binding force and acid resistance during printing, the paste has good surface appearance after printing, and the conductive silver paste can be suitable for products with smaller specifications and sizes.

The invention relates to the technical field of membrane separation, and discloses a polythiourea composite nanofiltration membrane as well as a preparation method and application thereof. The composite nanofiltration membrane comprises a bottom layer, a porous support layer and a polythiourea separation layer which are arranged in sequence, wherein the polythiourea separation layer comprises a structural unit A from polyamine and a structural unit B from a polyisothiocyano compound; wherein the structural unit A and the structural unit B are connected through a structure shown in a formula I, Ar1 is a residue obtained after a reaction of a compound containing polyisothiocyano groups, and Ar2 is a residue obtained after a reaction of polyamine. The separation layer structure of the polythiourea composite nanofiltration membrane contains C = S bonds, a large number of hydrogen bonds can be formed, the polythiourea composite nanofiltration membrane has excellent chemical stability, the structural stability of the composite nanofiltration membrane in a strong acid environment is remarkably improved on the premise that the separation performance of the composite nanofiltration membrane is guaranteed, and the acid resistance of the composite nanofiltration membrane is improved.

The invention relates to the technical field of adhesives, in particular to a flexible circuit board covering film and a preparation method thereof.The covering film is composed of a release film, a photo-thermal dual-curing composition and a polyimide film from top to bottom; the photo-thermal dual-curing composition is prepared from the following components in parts by weight: 80 to 125 parts of acrylic acid prepolymer, 8 to 25 parts of benzoxazine-novolac epoxy resin, 0.1 to 10 parts of photoinitiator, 0.1 to 5 parts of photosensitizer and 10 to 100 parts of solvent I. Due to the existence of the photo-thermal dual-curing composition, the peel strength of the cover film after photo-curing and thermal curing reaches 1.4 N / mm; the benzoxazine-novolac epoxy resin is applied to the cover film of the flexible circuit board, so that the cover film has acid resistance and high temperature resistance; by controlling the glass-transition temperature of the acrylic prepolymer, the requirements of high peel strength and high weather resistance of the cover film are met at the same time, so that the properties of the cover film in all aspects reach a balanced state.

The application discloses a kind of corrosion-resistant aluminum alloy profiles and preparation method thereof, belong to aluminum alloy profile technical field.The application can ensure the strength of aluminum alloy profile by optimizing the composition of corrosion-resistant aluminum alloy, and has a positive effect on the corrosion resistance of aluminum alloy profile.In addition, the application forms a corrosion-resistant coating on the surface of the corrosion-resistant aluminum alloy substrate by laser cladding, which can significantly improve the corrosion resistance of the aluminum alloy profile while ensuring the application performance of the aluminum alloy profile.In the corrosion-resistant coating, nickel powder can enhance the resistance to pitting and intergranular corrosion, and improve the adhesion to the aluminum alloy substrate.Boron nitride can improve the surface acid resistance and wear resistance of the aluminum alloy profile, and block the corrosion channel.Lanthanum oxide and cerium dioxide have a synergistic effect, which can refine the surface grains, reduce the pores generated during the cladding process, improve the compactness of the coating, promote the compatibility with the aluminum alloy substrate, and ensure the appearance quality of the aluminum alloy profile.

Disclosed in the present invention are an acid-resistant noble metal ion adsorption film and a preparation method therefor. The preparation method comprises: a) pretreatment of a base film: firstly, cleaning and drying a silicon carbide substrate to obtain a clean film; then performing oxidation treatment on the clean film to obtain a micro-oxidation film; and finally, placing the micro-oxidation film in a strong acid solution for acidification treatment, to obtain a base film modified with a hydroxyl functional group; b) the growth of an MOF seed crystal: placing the obtained base film modified with the hydroxyl functional group into a seed crystal growth solution, and reacting at 110-130°C for 12-24 hours to obtain a film loaded with the MOF seed crystal; and c) MOF secondary growth: placing the prepared film loaded with the MOF seed crystal into a secondary growth solution, and reacting at 110-130°C for 20-30 hours to obtain the acid-resistant noble metal ion adsorption film. The adsorption film prepared according to the present invention has good acid resistance, and can achieve efficient and stable recovery of rare noble metals in a strong acid environment.

The invention relates to the technical field of metallurgy, in particular to a heat treatment process for improving the HIC resistance of a Q345R (HIC) steel plate, which comprises the following steps of: heating the steel plate to 30-50 DEG C above AC3, keeping in-furnace time for more than or equal to 30 minutes, and then cooling in two stages: in the first stage, quickly cooling, namely cooling to Ar1 temperature at the speed of 25-30 DEG C / s; in the second stage, the cooling speed is reduced, and cooling is conducted to the Bs temperature at the speed of 2-5 DEG C / s; and then air-cooling to room temperature. The phase change degree of the steel plate is controlled by adopting a two-stage cooling mode, so that the final structure of the steel plate is changed, the purposes of reducing the banded structure and improving the acid resistance of the Q345R (HIC) steel plate are achieved, and good social and economic benefits are achieved.

The present invention discloses a photothermal conversion super-hydrophobic wind turbine blade surface protective coating and a preparation method thereof. The coating is mainly composed of a fluorinated silicone waterborne polyurethane-fluorinated acrylate dispersion modified by a photothermal conversion modified nano slurry. On the one hand, the dispersion effect of the photothermal conversion nano slurry is improved. On the other hand, the evenly dispersed photothermal conversion nano particles ensure the photothermal conversion effect of the super-hydrophobic wind turbine blade surface protective coating coating, making the surface moisture of the coating easy to volatilize and difficult to freeze. Even if it freezes, it has the advantage of being easy to melt and drip. Compared with the wind turbine blade surface protective coating with a single function and an insufficient anti-icing effect on the current market, the photothermal conversion super-hydrophobic wind turbine blade surface protective coating of the present invention has a particularly outstanding anti-icing effect, and the ice adhesion is as low as below 20kPa; at the same time, the coating also has the advantages of simple and easy process, environmental protection, resistance to wet and heat aging and ultraviolet aging, acid resistance, and safe use.

The invention relates to a corrosion-resistant coating and a preparation method thereof. The corrosion-resistant coating comprises a component A and a component B, the component A comprises the following components in parts by weight: 40-60 parts of epoxy resin, 20-40 parts of pigments and fillers, 1-5 parts of auxiliaries and 10-50 parts of deionized water; the component B comprises 40-60 parts of a water-based curing agent, 1-5 parts of a tea polyphenol-modified graphene composite material and 30-50 parts of deionized water; wherein the mass ratio of the component A to the component B is (4-7): 1. Compared with the prior art, the paint obtained by the invention has the characteristics of low water absorption, strong cohesiveness, excellent acid resistance, alkali resistance, salt mist resistance and corrosion resistance when being applied to a metal coating.

The invention discloses glass powder and conductive copper paste for an MLCC (multilayer ceramic capacitor) and a preparation method of the glass powder and the conductive copper paste. The formula of the glass powder comprises 18.0% to 28.0% of SiO2, 25.0% to 35.0% of B2O3, 30.0% to 45.0% of BaO, 0% to 10% of CaO, 0% to 5% of Na2O, 0% to 8.0% of TiO2, 0% to 6% of CuO, 0% to 5.0% of Sb2O3 and 0% to 5.0% of NaF. Basic components of the glass powder do not contain Bi and Zn, a system is SiO2-B2O3-Na2O-BaO, TiO2, CuO, Sb2O3, NaF and the like are added into the basic glass components, Sb2O3 can reduce the surface tension of the glass and improve the wettability between the glass and the copper powder and ceramic, and TiO2 and CuO enhance the acid resistance of the glass and increase the compactness of an interface. NaF is used as a glass liquid clarifying agent, so that the clarifying speed of the glass liquid can be increased, the high-temperature viscosity of the glass powder can be reduced, the flowability of the glass powder is enhanced, and the interface densification speed is increased. The average particle size of the glass powder is 1.8-2.5 microns, and the thermal expansion coefficient of the glass is 6.5-9.5 ppm / DEG C. The glass powder has an obvious sintering assisting effect on the copper paste, after the copper paste is applied to an MLCC ceramic substrate to be sintered, the copper paste and the ceramic substrate have firm physical and chemical bonding, and the MLCC shows excellent electrical properties, adhesive force and good electroplating liquid resistance.

A purpose of the present invention is to provide an alkali-free glass which has a low dielectric loss tangent in a high-frequency region and is excellent in terms of acid resistance, moisture resistance, and phase separation property. The present invention relates to an alkali-free glass comprising, in terms of oxide amount in mol%, 50-76 SiO2, 2-6 Al2O3, 18-35 B2O3, 1-6 MgO, 0.5-5 CaO, 1-5 SrO, and 0-3 BaO and having a value of expression (A) of 3.5-6, a value of expression (B) of -2 to 2, a value of expression (J) of 0.2-0.7, and a value of Δβ-OH of 0 mm-1 to 0.1 mm-1.

The invention relates to an acid-resistant nanofiltration membrane and a preparation method thereof, and relates to the technical field of nanofiltration membranes. The acid-resistant nanofiltration membrane comprises a supporting base layer and a functional layer, the functional layer is formed by interfacial polymerization on the supporting base layer, the supporting base layer comprises a polyetherimide-nanomembrane, raw materials of the functional layer comprise an oil-phase solution and a water-phase solution, the oil-phase solution comprises 1, 3, 5-benzene trisulfonyl chloride and an oil-phase solvent, and the water-phase solution comprises 1, 3, 5-benzene trisulfonyl chloride and a water-phase solvent. The water-phase solution comprises piperazine and a water-phase solvent; the method has the effect of improving the acid resistance of the nanofiltration membrane.