1882 results about "Polyacrylonitrile" patented technology

The invention discloses a silicon negative electrode material as well as a preparation method and application thereof, and belongs to the technical field of lithium ion batteries. The silicon negative electrode material comprises a silicon material substrate and a coating layer coating the surface of the silicon material substrate, the coating layer comprises cyclized polyacrylonitrile and a fast ion conductor. According to the silicon negative electrode material provided by the invention, a uniform cyclized polyacrylonitrile and fast ion conductor coating layer is constructed on the surface of a silicon material matrix. The good electronic conductivity and elasticity of the cyclized polyacrylonitrile and the excellent ionic conductivity of the fast ion conductor are beneficial to buffering the volume expansion of the silicon carbon material, accelerating the lithium ion transmission kinetics and effectively improving the rate capability of the negative electrode material; the cyclized polyacrylonitrile has high chemical stability and strong compatibility with the silicon material and the sulfide solid electrolyte, and is used as a buffer layer between the silicon material and the sulfide solid electrolyte to avoid direct contact between the silicon carbon material and the sulfide solid electrolyte, inhibit interface side reaction and effectively improve the cycle stability of the battery.

The invention provides a preparation method of a waterproof flame-retardant multifunctional fabric, and belongs to the technical field of functional textiles. The preparation method comprises the following steps: heating dihydric alcohol until the dihydric alcohol is completely melted, adding diisocyanate, a flame retardant and a catalyst, reacting to obtain a polyurethane prepolymer, adding a chain extender for chain extension, then adding an end-capping reagent for end capping, cooling, adding an emulsifier to obtain a waterproof flame retardant emulsion, adding water to form a finishing agent, soaking a polyacrylonitrile pre-oxidized fiber fabric in the finishing agent for treatment, and drying to obtain the waterproof flame retardant fabric. And pre-drying and baking to obtain the multifunctional fabric. Polyhydric alcohol with a long alkane chain is adopted to carry out chain extension on a polyurethane prepolymer, the obtained waterproof agent has good film-forming property, can be firmly fixed on the surface of a fiber without the help of a cross-linking agent or an adhesive during application, and endows a modified textile with excellent washing fastness.

The invention discloses a preparation method of a composite phase-change temperature-adjusting organic fiber membrane with a flexible core-shell structure, and belongs to the field of intelligent textile materials.The preparation method comprises the following steps that polyacrylonitrile (PAN) serves as a sheath layer material, n-octadecane serves as a core layer phase-change material, and the composite phase-change fiber membrane is prepared through a melt spinning method and a coaxial electrostatic spinning technology. According to the invention, the fiber membrane with high melting enthalpy value (171.6 J / g), excellent thermal stability (the latent heat is still 117.7 J / g after 100 times of heating-cooling circulation) and excellent mechanical properties (the tensile strength is 2.418 MPa, the tensile yield stress is 2.331 MPa, the tensile strain at break is 36.5%, and the elastic modulus is 58.226 MPa) can be prepared; a new thought is provided for preparing intelligent textiles with good flexibility and efficient heat management capability.

The invention relates to a wave-absorbing and vibration-reducing method for dynamic disturbance of an asymmetric high-stress tunnel, which belongs to the technical field of tunnel excavation, and specifically comprises the following steps: step 1, determining the position, range and depth of an asymmetric stress concentration area or a rockburst potential risk area behind a high-stress tunnel face, and determining the position, number and depth of grouting holes; 2, preparing and grouting a wave-absorbing material, and solidifying the wave-absorbing material, wherein the wave-absorbing material comprises the following components: cement, water, a foaming agent, polyacrylonitrile fiber and rubber powder; thirdly, monitoring holes are drilled in the middle and the two ends of the wave-absorbing grouting area, and a vibration sensor is placed in each monitoring hole; and 4, after the vibration sensor monitors that the high-energy disturbance stress wave is transmitted, obtaining an amplitude value through the waveform of the disturbance wave to obtain the main frequency of the disturbance wave. The specific position of wave-absorbing grouting is provided for a rockburst risk area, and the disturbance wave monitoring method provided by the invention can realize disturbance wave attenuation effect evaluation for various disturbance waves.

The invention belongs to the technical field of membrane material preparation and water treatment, and discloses a La-MOF-COOH / AO-PAN composite membrane material and a preparation method and application thereof, and the preparation method of the membrane comprises the following steps: preparing a PAN membrane; preparing an AO-PAN membrane; the preparation method comprises the following steps: preparing La-MOF-COOH; and the preparation of the La-MOF-COOH / AO-PAN film is carried out. The composite membrane material is composed of modified polyacrylonitrile fibers, metal lanthanum and an organic ligand. Amino groups and hydroxyl groups in amidoximated PAN participate in hydrogen bonds and covalent interaction, so that the interfacial compatibility and stability of La-MOF-COOH and AO-PAN are improved, agglomeration of La-MOF-COOH filler is avoided, the structural uniformity, stability and functionality of the La-MOF-COOH / AO-PAN composite membrane are improved, and the composite membrane has a good application prospect.

The invention provides weather-resistant anti-freezing road concrete and a preparation method thereof, and belongs to the technical field of concrete. The concrete comprises the following components: sulphoaluminate cement, Portland cement, silica fume, fly ash, modified granite gravel coarse aggregate, medium sand fine aggregate, silica fume blended fiber, silica fume blended polyacrylonitrile fiber, a composite air entraining agent, a functional modifier, a composite antifreeze agent, pre-absorbent zeolite powder and the like. The preparation method comprises the following steps: modifying granite macadam with Al (H2PO4) 3, SiO2 and methoxypolyethylene glycol triethoxysilane, and modifying with a lithium silicate aqueous solution to obtain the modified granite macadam coarse aggregate. The composite air entraining agent comprises a JRY-Q air entraining agent and sodium alpha-olefin sulfonate. The functional modifier is prepared from gas phase method spherical nano silicon dioxide and nano alpha-Al2O3. The composite antifreeze agent comprises ethylene glycol butyl ether acetate and modified calcium carbonate. The modified calcium carbonate is obtained by sequentially modifying nano calcium carbonate with calcium chloride, a KH-550 silane coupling agent and stearic acid.

The invention relates to the field of textile fabrics, and particularly discloses an antibacterial and crease-resistant garment fabric and a preparation process thereof. The antibacterial and crease-resistant garment fabric is prepared from modified cotton fibers and electrospun fibers of polyacrylonitrile and polyurethane according to the mass ratio of 1: (0.1-0.3): (0.3-0.5), and a preparation method of the polylactic acid fiber modified cotton fibers containing silver nanowires comprises the following steps that the cotton fibers are padded in finishing liquid and then dried and shaped, and pretreated cotton fibers are prepared; the pretreated cotton fibers are padded in the treating fluid and then dried and baked, and modified cotton fibers are prepared; the finishing liquid is prepared from the following raw materials: citric acid modified titanium dioxide sol, sodium hypophosphite, triethanolamine and deionized water; the treating fluid is prepared from the following raw materials: nylon waste silk, chitosan quaternary ammonium salt, N, N-dimethylformamide and alkaline silica sol. The garment fabric has the advantages of being good in antibacterial and crease-resistant effect, lasting in antibacterial effect and high in breaking strength.

The invention discloses a high-strength, high-conductivity and heat-resistant aluminum-based composite material. The aluminum-based composite material is formed by compounding and sintering 90-95 wt% of an aluminum alloy matrix and 5-10 wt% of a conductive fiber membrane. A trace amount of Zr, Hf and B elements are added into the aluminum alloy matrix, and the effects of refining grains, purifying impurities and improving the electric conductivity, heat resistance and comprehensive mechanical performance of the alloy matrix can be achieved. The conductive fiber membrane is a polyaniline / polyacrylonitrile composite conductive fiber membrane doped with nano-copper particles and cerium oxide particles, and polyaniline and polyacrylonitrile blended spinning can improve the strength and stability of the fiber membrane. And the conductivity of the fiber membrane and the bonding strength of the fiber membrane and an aluminum alloy matrix can be further improved through doping of the nano-copper particles and the cerium oxide particles. The aluminum-based composite material disclosed by the invention has good electrical conductivity and heat resistance and excellent comprehensive mechanical properties.

The invention discloses a polyacrylonitrile carbon fiber and a preparation method thereof, and the method comprises the following steps: (1) copolymerizing acrylonitrile and acrylamidine to obtain a polymer spinning solution; (2) sequentially carrying out spinning, solidification forming, first-stage drafting, washing, oiling, drying, second-stage drafting and heat setting on the polymer spinning solution to obtain a polyacrylonitrile precursor; and (3) sequentially carrying out pre-oxidation and carbonization treatment on the polyacrylonitrile precursor to obtain the polyacrylonitrile carbon fiber. Therefore, by adopting the method, the radial structure difference of the nascent fiber can be effectively controlled, the radial structure of the obtained nascent fiber is more homogeneous, and the radially homogeneous polyacrylonitrile precursor is obtained, so that the prepared carbon fiber is more excellent in performance or larger in diameter, and meanwhile, an ammonification process link is omitted.

The invention belongs to the technical field of wall joint filling, and relates to a wall cracking joint filling agent and a wall joint filling process, the wall cracking joint filling agent comprises a cement-based cementing material, fine aggregate, modified toughening fiber, modified nano zinc oxide, a dispersing agent, a defoaming agent, a water-retaining agent and a mildew preventive; the modified toughened fiber is obtained by sequentially carrying out alkali etching, dopamine coating and intercalated kaolin loading on polyacrylonitrile fiber; the modified nano-zinc oxide is obtained by modifying nano-zinc oxide through a silane coupling agent and coating and modifying the nano-zinc oxide through chitosan. According to the wall crack repairing agent provided by the invention, the modified toughening fibers and the modified nano zinc oxide which are subjected to surface functionalization treatment are introduced, so that the crack resistance and toughness of a cement-based crack repairing material can be remarkably improved, the occurrence probability of secondary cracking after repairing can be remarkably reduced, meanwhile, lasting and effective mildew-proof and antibacterial capabilities can be provided, microbial erosion can be inhibited, and the service life of the wall crack repairing agent is prolonged. And good construction operability and basic mechanical properties of the material are maintained.

The invention relates to the field of temperature-adjusting fibers, and particularly discloses a preparation method of a phase-change temperature-adjusting fiber. The phase-change temperature-adjusting fiber is of a core-shell composite structure, a core layer is a lyocell fiber with wood pulp as a raw material, phase-change microcapsules are arranged on the fiber, octadecane serves as a phase-change material, and the phase-change microcapsules are formed by wrapping melamine-formaldehyde resin formed by condensation of melamine and formaldehyde. The outer layer is a shell fiber which is formed by blending polyacrylonitrile and cellulose acetate, the surface of the shell fiber contains structures such as pores, micropores and cracks, and nano titanium dioxide particles capable of absorbing ultraviolet rays are attached to the shell fiber. Experiments prove that the phase-change temperature-regulating fiber not only has a phase-change temperature-regulating function, but also has the effects of ultraviolet resistance, moisture permeability and sweat releasing. The phase-change temperature-adjusting fiber is used as a raw material, and is blended and woven with other fibers to prepare the temperature-adjusting functional fabric.

The invention relates to a preparation method of a carbon fiber reinforced carbon aerogel heat insulation composite material, which comprises the following steps: firstly, pre-oxidizing a commercial polyacrylonitrile (PAN) needled felt reinforcement at 195-255 DEG C to obtain pre-oxidized felt reinforcements with different pre-oxidation degrees; uniformly mixing phenolic resin serving as an organic sol raw material, hexamethylenetetramine serving as a cross-linking curing agent and normal propyl alcohol serving as a solvent according to a proper proportion to form organic sol; secondly, the pre-oxidized felt blank body is placed in a stainless steel mold, organic sol is poured into the stainless steel mold, the pre-oxidized felt is completely immersed in the sol, and the pre-oxidized felt reinforcement is fully soaked in the organic sol under the vacuum negative pressure condition; sealing the stainless steel mold dipped with the pre-oxidized felt, and curing and aging for 40-80 hours at 80 DEG C to obtain pre-oxidized felt reinforced organic wet gel; placing the wet gel at room temperature for 24 hours, and drying the wet gel in an air dry oven at 60 DEG C for 72 hours to obtain pre-oxidized felt reinforced organic aerogel; and finally, carbonizing the pre-oxidized felt reinforced organic aerogel at 850-1100 DEG C for 3 hours by using a vacuum carbonization furnace at a heating rate of 3-5 DEG C / min to obtain the carbon fiber reinforced carbon aerogel composite material.

The invention relates to a defect-free ultrathin continuous MOF (Metal Organic Framework) film as well as a preparation method and application thereof. The MOF membrane is synthesized by taking an amidoxime functionalized commercial polyacrylonitrile ultrafiltration membrane as a support body through a diffusion method, and the thickness of the MOF membrane is 22 nm to 1.36 microns. The preparation method comprises the following steps: firstly, respectively preparing aqueous solutions of Fe < 3 + > salt and organic ligands, then respectively placing the aqueous solutions on two sides of a support body, and synthesizing the defect-free ultrathin continuous MOF membrane at room temperature by utilizing a pair diffusion method. Compared with the prior art, the thickness of the defect-free ultrathin continuous MOF membrane is controllable, the minimum thickness can reach 22 nm, the membrane flux and the rejection rate of organic pollutants can be regulated and controlled, the defect-free ultrathin continuous MOF membrane has photocatalytic degradation performance, organic pollutants can be treated through membrane separation and photocatalytic coupling technologies, and the defect-free ultrathin continuous MOF membrane has great application value in the field of wastewater treatment.

The invention belongs to the technical field of novel adsorption materials, and particularly relates to needle-punched cloth for extracting uranium from seawater based on dry-process PAN fibers and a preparation method and application of the needle-punched cloth. The needle-punched fabric for extracting uranium from seawater comprises chemical modified functional fibers and supporting fibers, the chemically modified functional fiber with amidoxime groups is obtained by chemically modifying a dry polyacrylonitrile short fiber. The invention discloses the needle punched cloth for extracting uranium from seawater based on the dry PAN fiber for the first time, the material has the advantages of low production cost, batch production and large-scale implementation, can be directly soaked in seawater, can be rolled into components such as a filter element and the like, and can be used for enriching and separating uranium from seawater in forms of single-layer filtration, multi-stage filtration and the like; the industrial popularization and application are easy.

The invention discloses a preparation method of a porous few-layer carbon nitride / amidoxime-based seawater uranium extraction composite material with a multilevel structure, and relates to the field of seawater uranium extraction materials. The composite material is a porous few-layer carbon nitride material with high photocatalytic performance obtained by repeatedly calcining melamine at a high temperature; polyacrylonitrile is subjected to amidoxime functionalization, and a polyamidoxime solution is obtained; uniformly dispersing porous few-layer carbon nitride in the polyamidoxime solution, and adding a sacrificial pore-forming agent polyvinylpyrrolidone at the same time to obtain a spinning solution; and finally, preparing the porous few-layer carbon nitride / amidoxime-based seawater uranium extraction composite material with high adsorption performance by utilizing a one-step electrostatic spinning technology. The obtained composite material has excellent uranium adsorption performance and adsorption rate and can be recycled, the preparation method is simple in process and free of pollution to the environment, and the prepared composite material has excellent uranium adsorption performance and adsorption rate, can be recycled and has wide application prospects in the field of uranium extraction from seawater.

The invention provides a modified carbon nanofiber as well as a preparation method and application thereof. The preparation method comprises the following steps: S1, dissolving polyacrylonitrile in N, N-dimethylformamide, so as to obtain an electrostatic spinning precursor solution; s2, performing electrostatic spinning treatment on the electrostatic spinning precursor solution to obtain an electrostatic spinning nanofiber material; s3, sequentially carrying out pre-oxidation and graphitization treatment on the electrostatic spinning nanofiber material to obtain unmodified carbon nanofibers; and S4, soaking the unmodified carbon nanofibers in a K2FeO4 solution, and sequentially carrying out first drying, calcination and acidification treatment to obtain the modified carbon nanofibers. The carbon nanofiber has more active sites, high specific surface area and good conductivity and hydrophilicity, can remarkably improve the energy density and cycling stability of a battery when being used for an electrode material, and can provide powerful technical support for the development of the field of new energy.

The invention provides a preparation method of high-performance polyacrylonitrile pre-oxidized fibers, and belongs to the technical field of preparation of carbon filaments from polyacrylonitrile. The preparation method comprises the following steps: adding hydroxylated carbon nanotubes into deionized water, performing ultrasonic dispersion, adding a modifier and a catalyst, continuing ultrasonic dispersion, heating to 80-90 DEG C, performing constant-temperature reaction, fully washing with water, and drying to obtain modified carbon nanotubes; dispersing the modified carbon nanotube in an N, N '-dimethylformamide solution, adding an acrylonitrile monomer, hydroxyethyl acrylate and an initiator, copolymerizing to form a carbon nanotube / acrylonitrile copolymer, and spinning to obtain a carbon nanotube / acrylonitrile copolymer fiber; the carbon nano tube / acrylonitrile copolymer fiber is placed in a microwave treatment device, and a plurality of microwave generators are arranged in the microwave treatment device and are used for carrying out segmented pre-oxidation on the carbon nano tube / acrylonitrile copolymer fiber. The problems that an existing polyacrylonitrile fiber pre-oxidation technology is high in energy consumption and low in strength, poor in flame retardance and the like due to the difference between internal and external pre-oxidation effects can be solved.

The invention relates to the technical field of batteries, in particular to a diaphragm, a preparation method thereof and a lithium ion battery. The diaphragm comprises a base membrane and a coating located on the surface of at least one side of the base membrane, the base membrane comprises a polyvinyl alcohol membrane and first particles dispersed in the polyvinyl alcohol membrane, and the first particles comprise at least one of boehmite, aluminum oxide and zirconium oxide; the coating comprises second particles and a first binder, and the second particles comprise at least one of attapulgite, zeolite, sepiolite, montmorillonite and diatomite; the first binder comprises at least one of polyacrylonitrile, polyacrylic acid, an acrylic acid-acrylonitrile copolymer, an acrylic acid-acrylamide copolymer, an acrylonitrile-acrylamide copolymer, an acrylic acid-acrylonitrile-acrylate copolymer, an acrylic acid-acrylonitrile-acrylamide copolymer and an acrylic acid-acrylonitrile-acrylate copolymer. The diaphragm disclosed by the invention is good in thermal stability and liquid absorbency; comprising the diaphragm disclosed by the invention can improve lithium dendrites and cycle performance.

The invention discloses a thermally stable gas diffusion layer material and a fuel cell, and relates to the field of fuel cells. When the heat-stable gas diffusion layer material is prepared, short-cut polyacrylonitrile carbon fibers are subjected to papermaking and then cured, and 3-aminothiophene is oxidized and grafted to prepare a modified carbon paper base layer; the preparation method comprises the following steps: carrying out a reaction on a single-layer graphene oxide nanosheet, 6-amino-2-mercaptobenzothiazole and 3-aminoethyl thiophene to prepare a modified single-layer graphene oxide nanosheet; the preparation method comprises the following steps: reacting polyvinylidene fluoride powder, 3-allyl thiophene and single-ended vinyl silicone oil to prepare a modified polyvinylidene fluoride emulsion; and uniformly mixing the modified single-layer graphene oxide nanosheet, a modified polyvinylidene fluoride emulsion and isopropanol, spraying on the modified carbon paper base layer, and reacting with 3, 4-ethylenedioxythiophene to prepare the thermally stable gas diffusion layer material. The thermally stable gas diffusion layer material prepared by the method has excellent porosity, thermal stability, conductivity and corrosion resistance.

Recycling wind turbine blades includes shredding, crushing, and milling the wind turbine blades to yield a multiplicity of particles including glass fiber and sieving the particles to yield a multiplicity of pellets including glass fibers. Manufacturing a composite coaxial fiber includes providing a first, second, and third polymer composition to yield a composite coaxial fiber precursor, processing the composite coaxial fiber precursor to yield a coagulated composite coaxial fiber precursor, drawing the coagulated composite coaxial fiber precursor, and heating the drawn coagulated composite coaxial fiber precursor to yield the composite coaxial fiber. The second polymer composition can include the recycled glass fibers. The resulting composite coaxial fiber includes an inner and outer layer including polyacrylonitrile and a middle layer between the inner layer and the outer layer. The middle layer includes polyacrylonitrile and a multiplicity of the recycled glass fibers.

The invention belongs to the field of intelligent wearing, and discloses a multifunctional wearable composite fiber membrane and a preparation method and application thereof. The multifunctional wearable composite fiber membrane is of a sandwich structure, the upper layer is a fullerene hybridized phosphorene modified polyacrylonitrile membrane, the lower layer is a polyurethane membrane, and the middle layer is a silver nanowire layer. The preparation method comprises the following steps: firstly, preparing fullerene hybridized phosphorene nanosheets, dispersing the fullerene hybridized phosphorene nanosheets into a solvent to obtain fullerene hybridized phosphorene dispersion liquid, adding the fullerene hybridized phosphorene dispersion liquid into a polyacrylonitrile solution, stirring to obtain a fullerene hybridized phosphorene / polyacrylonitrile spinning solution, and carrying out electrostatic spinning to obtain the fullerene hybridized phosphorene modified polyacrylonitrile fiber membrane. And then rolling or spraying a silver nanowire layer, covering one side of the silver nanowire layer with a polyurethane fiber membrane, drying and pressing to obtain the composite material. The composite fiber membrane prepared by the invention has good mechanical properties, air permeability, one-way moisture conduction performance, antibacterial performance, heat dissipation performance, electromagnetic shielding performance and flame retardant performance, and has a wide application prospect in the field of flexible wearable intelligent equipment.

The invention discloses a preparation method of a high-performance polyacrylonitrile-cellulose nanocrystalline composite battery diaphragm, and belongs to the technical field of lithium ion battery diaphragms. The preparation method comprises the following steps: mixing cellulose nanocrystals, polyacrylonitrile and a solvent to obtain a spinning solution; and carrying out electrostatic spinning on the spinning solution to obtain the high-performance polyacrylonitrile-cellulose nanocrystalline composite battery diaphragm, the mass of the cellulose nanocrystal is 1-10% of the sum of the mass of the cellulose nanocrystal and the mass of the polyacrylonitrile; the cellulose nanocrystals are obtained by hydrolyzing sisal hemp cellulose through phosphoric acid. The polyacrylonitrile-cellulose nanocrystalline composite battery diaphragm disclosed by the invention has excellent thermal stability, mechanical property and electrolyte wettability, and has good cycle stability when being applied to a lithium ion battery. Meanwhile, the raw materials of the cellulose nanocrystals are wide in source, low in price and environment-friendly, and the production cost of the diaphragm is reduced by taking the cellulose nanocrystals as one of the raw materials.

The invention discloses a preparation method of a high-crosslinking-degree polyamide solvent-resistant nanofiltration membrane, and belongs to the technical field of water and solvent treatment. Polyacrylonitrile (PAN) is used as a base membrane, an iron oxyhydroxide (FeOOH) middle layer is prepared through in-situ hydrolysis, then polyamine monomers and high-activity acyl chloride monomers react to synthesize a polyamide separation layer, and finally the polyamide solvent-resistant composite nanofiltration membrane with the adjustable crosslinking degree is prepared. The method has the advantages that the process is simple and mature, the conditions are green and mild, the surface hydrophilicity of the middle layer can be reasonably regulated and controlled through hydrolysis process parameters, the thickness of the polyamide separation layer is reduced, and the membrane flux is improved; meanwhile, due to the use of the rigid polyamine monomer, the prepared solvent-resistant nanofiltration membrane has a high degree of crosslinking, is endowed with good solvent resistance, can stably remove small molecular pollutants (the molecular weight is 200-1000Da) in solvents such as ethanol, acetone and tetrahydrofuran, and has a relatively wide application prospect.

The invention discloses a metal-free catalyst ZrC whisker as well as a preparation method and application thereof, and belongs to the technical field of ultrahigh-temperature ceramic materials. The preparation method comprises the following steps: dissolving a zirconium source and sodium fluoride in N-N, dimethylformamide to prepare a metal salt solution; adding a carbon source into the metal salt solution to obtain a spinning precursor solution; wherein the carbon source is simultaneously used as a carbon source and a spinning auxiliary agent, and the carbon source is polyacrylonitrile or polyvinylpyrrolidone; carrying out electrostatic spinning by adopting the spinning precursor solution to obtain a primary spun yarn; and carrying out high-temperature carbonization on the initial spinning yarns to obtain the ZrC crystal whiskers. As no metal catalyst is used, the ZrC whisker prepared by the method is free of impurities and high in purity, and large-scale and simple preparation of the ZrC whisker can be realized.

The invention discloses a phase-change heat-storage fluffy fiber and a preparation method thereof. According to the method, polyethylene glycol, microcapsules, fatty acid, paraffin or alkane and the like are used as phase change heat storage materials, elastic polymers such as polystyrene, polyurethane, polyamide and the like are used as elastic spinning materials, and hydrophobic polymers such as polyacrylonitrile, polysulfone, polytetrafluoroethylene, polyvinylidene fluoride and the like are used as hydrophobic spinning materials; the phase-change heat-storage fluffy fiber is prepared in a high-humidity environment through an electrostatic spinning method. The phase-change heat-storage fluffy fiber synthesized by the method is in a flexible fluffy form and has the advantages of good phase-change stability, low heat conductivity coefficient and the like, and the environmental temperature is kept stable through an accompanying heat absorption or heat release effect when phase change occurs at the phase-change temperature; the material can be used as a thermal insulation filling material and has wide application prospects in human body and environment thermal management and other aspects.

The invention discloses a polyacrylonitrile pre-oxidation method and application thereof and a preparation method of polyacrylonitrile-based high-modulus carbon fiber, the polyacrylonitrile pre-oxidation method comprises the following steps: pre-oxidizing polyacrylonitrile in at least three temperature zones in sequence in an air atmosphere, the first three temperature zones are controlled according to the sequence of pretreatment: the temperature of the first temperature zone is controlled to be 180-230 DEG C, the temperature of the second temperature zone is controlled to be 210-260 DEG C, and the temperature of the third temperature zone is controlled to be 250-300 DEG C. According to the method, the cyclization degree of the fiber in the pre-oxidation stage is used as a structure control index, and the pre-oxidation fiber with a perfect structure is prepared through regulation and control design of key parameters such as the pre-oxidation temperature, the drafting rate and the retention time, so that the high-model carbon fiber is prepared.

The invention relates to a dry-jet wet-spinning ultra-high-performance polyacrylonitrile-based carbon fiber and a preparation method thereof, and belongs to the technical field of carbon fibers. A preparation method of dry-jet wet-spinning ultra-high-performance polyacrylonitrile-based carbon fiber comprises the following steps: S1, mixing acrylonitrile, a comonomer, a chain transfer agent, an initiator and a solvent, carrying out polymerization reaction through a solvent dropwise addition method, and preparing a spinning solution; wherein the comonomers comprise a first comonomer, a second comonomer and a third comonomer; s2, the spinning solution is subjected to solidification, water washing, water drawing, oiling, drying and steam drawing, and precursor fibers are obtained; s3, the precursor fiber is sequentially subjected to pre-oxidation, low-temperature carbonization, high-temperature carbonization, graphitization, surface treatment, sizing and drying, and the ultra-high-performance polyacrylonitrile-based carbon fiber is prepared. Wherein the pre-oxidation adopts four-stage pre-oxidation treatment. The strength and modulus of the carbon fiber can be effectively and synergistically optimized, and the carbon fiber with high strength and high modulus is prepared.

The application belongs to the technical field of membrane separation materials, and discloses an ultrahydrophilic oil-water separation membrane, a preparation method and application thereof, and comprises the following steps: 2-(2-bromoisobutyryloxy)ethyl methacrylate monomers are prepared from 2-hydroxyethyl methacrylate and 2-bromoisobutyryl bromide, and a polymer with an atom transfer radical polymerization initiator is prepared through a free radical polymerization reaction; the polymer with the atom transfer radical polymerization initiator and polyacrylonitrile are dissolved into a solvent, and a PAN / P(AN-g-BIEM) blended membrane is prepared through a non-solvent induced phase separation method; and a hydrophilic polymer brush is grafted to the surface of the PAN / P(AN-g-BIEM) blended membrane to obtain the ultrahydrophilic oil-water separation membrane; the ultrahydrophilic oil-water separation membrane prepared by the application has a high separation flux, excellent oil-water separation efficiency and separation performance for different oil-in-water emulsions.

The invention relates to a preparation method of a hydrophobic manganese-based low-temperature denitration catalyst. According to the catalyst, a composite oxide of CeO2 and MnO2 is used as an active component, and polyacrylonitrile submicron fibers are used as a carrier; a mixed solution of carbon tetrachloride and gamma-aminopropyltriethoxysilane is used as a hydrothermal solution substrate, a mixed solution of ethyl acetate and gamma-aminopropyltriethoxysilane is used as a hydrothermal solution supernatant, and a hydrothermal-electrostatic spinning method is adopted for preparation; on the basis of the mass of the polyacrylonitrile submicron fiber carrier, the mass percentage of the active component is 10-20%, and the mass ratio of CeO2 to MnO2 in the active component is 1: (1-2). The catalyst not only can be used for catalytically reducing NO into N2 at low temperature, but also can be used for filtering particles in flue gas, has excellent water and sulfur poisoning resistance, and has relatively high economic value and wide market application prospect.

A preparation method of a polyester nanofiltration membrane with high chlorine resistance and pollution resistance relates to the technical field of chlorine-resistant polyester nanofiltration membranes, and comprises the following steps: sequentially dipping a polyacrylonitrile support layer in an aqueous phase solution and an oil phase solution, carrying out condensation polymerization at 25-45 DEG C to generate a polyester selection layer on the surface, and finally heating and crosslinking at 45-65 DEG C to obtain the polyester nanofiltration membrane. The aqueous phase solution is a tannic acid aqueous solution, a rhamnose aqueous solution, a vitamin C aqueous solution or a chlorogenic acid aqueous solution, the preparation method is simple and low in cost, and the formed polyester nanofiltration membrane has high chlorine resistance and pollution resistance.