597 results about "Polysulfone" patented technology

The invention discloses a modified hollow fiber membrane which is composed of a separation layer, a supporting layer and a macroporous layer, the pore diameters of the separation layer, the supporting layer and the macroporous layer are sequentially increased, and a preparation method of the modified hollow fiber membrane comprises the following steps: weighing polyether sulfone / polysulfone, a pore-foaming agent, a solvent, an organic macromolecular additive and an inorganic salt additive according to the proportion to prepare a spinning solution; stirring and dissolving at 80-180 DEG C, centrifugally filtering, defoaming at 40-80 DEG C to obtain a spinning solution, carrying out coagulating bath on the spinning solution, molding, cleaning, stretching and drying to obtain the modified hollow fiber membrane. According to the preparation method, micromolecular inorganic salt pore-forming agents with different concentrations are added into a spinning solution and a coagulating bath, and interaction among inorganic salt, a polymer and a solvent is utilized, so that an inner skin layer structure and an outer skin layer structure of the hollow fiber membrane are adjusted, and a unique three-layer structure of a separation layer, a supporting layer and a macroporous layer is formed; the hydrophilic performance is stable, and the clearance on middle molecules is improved.

The invention relates to the technical field of reverse osmosis membranes, in particular to a polyamide reverse osmosis membrane for high-salinity wastewater treatment and a preparation method of the polyamide reverse osmosis membrane. The invention solves the problem that the polyamide reverse osmosis membrane cannot give consideration to both desalination rate and water flux. The polyamide reverse osmosis membrane comprises a polyester non-woven fabric layer, a polysulfone porous layer, a transition layer and a polyamide layer. The polysulfone porous layer is prepared, and the modified pore-forming agent is added to improve the water flux of the reverse osmosis membrane; the hydrophilicity of the reverse osmosis membrane is improved by preparing the transition layer and adding a hydrophilic auxiliary agent when the polyamide layer is prepared; the flux attenuation rate of the polyamide reverse osmosis membrane is reduced by preparing the polyamide layer; the desalination rate of the reverse osmosis membrane is improved by introducing a composite ion complexing agent and graphene quantum dots into the polyamide layer.

The invention relates to the technical field of reverse osmosis membrane supports, in particular to a polyester non-woven fabric and a preparation method and application thereof.The preparation method comprises the steps that S1, polyester main body fibers and polyester adhesive fibers are used as raw materials to prepare high-quantitation original cloth M0 and low-quantitation original cloth H0; carrying out hot pressing pretreatment on the H0 to obtain a product H0 '; s2, overlapping and hot-pressing M0 and H0 'to obtain a composite non-woven fabric M1H1; s3, the M1H1 is impregnated with a functional solution, and the functional solution contains para-aramid nanofibers and nano calcium carbonate modified by hexadecyl trimethyl ammonium bromide; and then carrying out cold pressing on the composite non-woven fabric impregnated with the functional solution to obtain the nano-material modified composite non-woven fabric. And S4, carrying out secondary hot pressing treatment to obtain the polyester non-woven fabric. The polyester non-woven fabric can effectively avoid the problems of excessive curling, excessive permeation of a polysulfone solution and the like during curing after being coated with polysulfone, and is more beneficial to application in a reverse osmosis membrane.

The present invention discloses a high-performance reverse osmosis membrane and a method for preparing the same. The reverse osmosis membrane comprises a polyester non-woven fabric layer, a polysulfone-based membrane, and a polyamide skin layer stacked in sequence. The polysulfone-based membrane has a micron-scale prism structure on the side away from the polyester non-woven fabric layer. The preparation method comprises coating the surface of the polyester non-woven fabric layer with the polysulfone-based membrane, and forming the micron-scale prism structure on the surface of the polysulfone-based membrane by cold pressing with a roller mold during the process of converting the polysulfone-based membrane from a liquid state to a solid state. The present invention improves the flux without affecting the desalination rate of the reverse osmosis membrane or sacrificing the thickness of the skin layer, thereby resolving the trade-off between flux and desalination in the current technology. At the same time, the micron-scale prism structure can be designed into different shapes according to performance requirements, thereby achieving precise control of the flux performance of the reverse osmosis membrane.

The present invention relates to the technical field of seawater desalination membranes, and discloses a durable seawater desalination membrane and a preparation method thereof. The present invention uses pentaerythritol as an initiator, uses propylene oxide and ethylene oxide as raw materials to synthesize a hyperbranched polyether, and then undergoes an ester exchange reaction with 2-aminoethyl acetate to synthesize a modified hyperbranched polyether. The ZIF-8 material is then synthesized by a hydrothermal method, and MoS2 nanosheets are coated on its surface to obtain a MoS2 / ZIF-8 composite material, which is then surface-modified by a silane coupling agent to obtain a modified MoS2 / ZIF-8 composite material. Finally, a casting solution is formed using polysulfone and a modified MoS2 / ZIF-8 composite material to obtain a base membrane, and the base membrane is then sequentially immersed in an aqueous phase solution and an oil phase solution to form a polyamide film layer, thereby obtaining a durable seawater desalination membrane. The seawater desalination membrane prepared by the present invention has excellent water flux, desalination rate and durability.

The invention provides a preparation method of a quick-dissolution reverse osmosis basement membrane, the reverse osmosis basement membrane prepared by the preparation method and application, and relates to the technical field of reverse osmosis basement membrane preparation. The preparation method comprises the following steps: mixing a pre-casting membrane solution containing polysulfone and a solution containing an amphiphilic block copolymer to obtain a casting membrane solution; coating the surface of a base material with the casting film solution to obtain the base material with a wet film layer; immersing the base material with the wet film layer into a coagulating bath, and obtaining a base film with a modified polysulfone layer through a non-solvent induced phase transformation method; sequentially contacting the base membrane with the modified polysulfone layer with a water-phase monomer solution containing m-phenylenediamine and an oil-phase monomer solution containing trimesoyl chloride, and curing to form a polyamide layer, so as to obtain the reverse osmosis base membrane capable of being quickly dissolved out. The TOC dissolution amount of the reverse osmosis membrane material can be effectively reduced, the TOC dissolution process is accelerated, it is ensured that the membrane can rapidly reach the preset water quality standard in the initial use stage, and the performance stability of the membrane is improved.

This disclosure relates to the fabrication of high-performance thin film composite (TFC) reverse osmosis (RO) membranes comprising a thin polyamide rejection layer (thickness of 100-200 nanometer), a porous substrate including polysulfone (PSf) layer (thickness of 40-50 micron) cast on polyester nonwoven fabric (thickness of ˜100 micron). Hydrophilic and antibacterial TFC polyamide RO membranes were developed by incorporating green Lignin and nanostructured silver-based metal organic frameworks (MOFs) into the selective layer. The polyamide layer of TFC RO membranes was fabricated on the porous PSf substrate by interfacial polymerization between aqueous monomer solutions containing MPD, and adequate additives in water and organic monomer solutions containing TMC in the mixture of hexane and co-solvents. The optimized produced RO membranes were provided water flux of 95-100 LMH and sodium chloride (NaCl) salt rejection of 98.5-99.0% during filtration of 2000 ppm NaCl solution at 225 psi pressure, and water flux of 55-60 LMH and sodium chloride (NaCl) salt rejection of 98.6-98.9% during filtration of 35000 ppm NaCl solution at 800 psi pressure. This disclosure also relates to developing a roll-to-roll PSf membrane as a substrate for making TFC RO membranes for water desalination

A membrane includes a polysulfone-based support, a polydopamine (PDA) layer disposed on a surface of the polysulfone-based support, and a silver / polydopamine (Ag / PDA) composite layer disposed on a surface of the polydopamine layer. The polysulfone-based support has a pore size of up to 600 nanometers (nm). The Ag / PDA composite layer contains core-shell structure particles and spherical particles. The core-shell structure particles have a silver nanoparticle core and a polydopamine shell. The spherical particles are silver-decorated polydopamine particles. The membrane can at least partially separate an Erichrome Black T (EBT) dye from an EBT dye / salt containing mixture by rejecting the EBT dye and allowing the EBT dye / salt containing mixture to pass through the membrane.

The invention provides a composite solid electrolyte membrane, a preparation method thereof and a solid lithium metal battery. The preparation method comprises the following steps that an organic-inorganic composite membrane is provided, the organic-inorganic composite membrane comprises organic components and inorganic components, and the organic components comprise polysulfone organic matter; and soaking the organic-inorganic composite membrane in a salt solution, and drying to obtain the composite solid electrolyte membrane. According to the invention, the polysulfone organic matter with high dielectric strength is introduced into the organic-inorganic composite membrane, so that the electrochemical window of the composite solid electrolyte membrane is remarkably improved, and the normal work of the battery in a relatively high voltage range is ensured.

The invention relates to a polyester composition as well as a preparation method and application thereof, and the polyester composition comprises the following components in parts by weight: 40-60 parts of polyester resin, 5-20 parts of a brominated flame retardant, 0.5-5 parts of a synergistic flame retardant, 0.1-15 parts of polysulfone, 0.05-5 parts of talcum powder and 15-40 parts of a reinforcing material, the polyester composition does not contain PFAS substances. On the basis of retaining a brominated flame-retardant system, polysulfone and talcum powder are combined with the brominated flame-retardant system, so that the flame-retardant property of the material under a thin wall is obviously improved under the condition of not using PFAS substances, and the application prospect of the polyester material is expanded.

A composite membrane for desalination includes a polyethylene terephthalate (PET) nonwoven layer having a fibrous structure, and has an average thickness of about 30 to 200 micrometers (μm). A polysulfone (PS) layer having an average thickness of about 30 to 100 μm is disposed on a surface of the PET nonwoven layer. Further, a polyamide layer is disposed on a surface of the PS layer including reacted units of an acyl compound, a phenylenediamine monomer, and a poly-(DADMAC-co-DADA). The polyamide layer has a rough surface including a plurality of irregular-sized ridge-and-valley structures of polyamide. The poly-(DADMAC-co-DADA) has a formula (I), and n is a positive integer.

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 relates to the technical field of antistatic agents, and particularly discloses an oil product antistatic agent and a preparation method thereof. The modified polysulfone is obtained by mixing and treating the following raw materials in parts by mass: 35-40 parts of xylene, 20-25 parts of composite polyamine, 15-20 parts of polysulfone, 5-8 parts of oligomeric dopamine and 1-2 parts of an activating agent, the preparation method comprises the following steps: taking composite polyamine, mixing with oligomeric dopamine, dispersing with xylene, then adding an activator, stirring, then adding polysulfone, and continuously treating, thereby obtaining the product. The preparation method of the composite polyamine comprises the following steps: taking epichlorohydrin, dispersing, adding a mixed amine source, heating, adding sodium carbonate, continuously stirring, cooling, adding a deprotection agent, filtering after treatment, taking a liquid part, drying by distillation, washing, drying again, and grinding to obtain the composite polyamine. The oil product antistatic agent prepared by the invention has relatively strong antistatic capability and relatively long duration time, and can form a firmer double-electric-layer structure.

The invention belongs to the technical field of new materials, and relates to a layered double hydroxide film using polysulfone resin as a binder, and the layered double hydroxide film is obtained by connecting layered double hydroxide particles or layered double hydroxide nanosheets into a continuous film by using the polysulfone resin as the binder. The invention further relates to a preparation method and application of the layered double hydroxide film with the polysulfone resin as the binder. The layered double hydroxide membrane provided by the invention adopts the LDH with anionic conductivity as a main body, and the surface resistance of the layered double hydroxide membrane in an alkaline solution is obviously lower than that of a commodity Zirfon membrane, so that the membrane provided by the invention can show higher electrolysis efficiency when being used for water electrolysis. The membrane forming method is based on the common phase inversion principle in separation membrane preparation in the field of chemical separation, so that large-scale preparation can be conveniently achieved through technological parameter change on the basis of mature industrial equipment for separation membrane phase inversion preparation, and batch preparation is easy to achieve.

The invention belongs to the technical field of membrane separation, and particularly relates to a low-pressure high-flux polyamide / polysulfone hollow fiber composite nanofiltration membrane and a preparation method thereof. The preparation method of the composite nanofiltration membrane comprises the following steps: dissolving sulfonated polysulfone, poly (1-vinyl-3-butylimidazole) bromide and polyvinylpyrrolidone to prepare a spinning solution, and spinning to obtain a base membrane; carrying out hydrophilic modification on the base membrane by using 1, 3-propane sultone; then, an aqueous phase solution containing poly (gamma-glutamic acid) and triethylene tetramine and an organic phase solution containing trimesoyl chloride and 3, 5-diaminobenzoic acid are subjected to interfacial polymerization in the inner cavity of the modified base membrane to form a polyamide separation layer; and finally, carrying out heat treatment to obtain the composite nanofiltration membrane. Through the synergistic effect of zwitterionic ionization of the base membrane and biomacromolecule construction of the separation layer, the mass transfer resistance of water is remarkably reduced, unification of high flux and high selectivity is achieved, and good structural stability is achieved.

The invention discloses a preparation method of polysulfone with stable color and reduced yellowness, which comprises the following steps: by using N-methyl pyrrolidone as a reaction solvent, reacting bisphenol A with 4, 4 '-dichlorodiphenyl sulfone in the presence of an acid-binding agent to generate polysulfone; wherein the N-methyl pyrrolidone contains N-methyl pyrrolidone peroxide, and the molar content of the N-methyl pyrrolidone peroxide in the N-methyl pyrrolidone is less than or equal to 0.05%. The polysulfone with stable color and reduced yellowness value can be synthesized by controlling the content of peroxide impurities in the N-methyl pyrrolidone.

The low-pressure reverse osmosis membrane comprises a non-woven fabric base material, a polysulfone porous supporting layer and a polyamide functional layer. According to the low-pressure reverse osmosis membrane, the non-woven fabric base material is adopted for providing basic support, the polysulfone porous supporting layer has proper thickness and pore diameter, and a stable and transparent supporting structure is established for the polyamide functional layer. Nano titanium dioxide particles are introduced into the polyamide functional layer, and the particle size and the content of the nano titanium dioxide particles and the thickness and the surface carboxyl density of the polyamide functional layer are accurately controlled. Nano titanium dioxide particles are uniformly dispersed in a polyamide network, so that the hydrophilicity and surface charge distribution of a separation layer are effectively improved, and the resistance of water molecules passing through the membrane is reduced, thereby realizing high water flux; meanwhile, the structural stability of the polyamide composite layer is enhanced, and the mechanical strength and pollution resistance of the membrane are improved. Charge distribution and hydrophilicity on the surface of the membrane are adjusted by proper carboxyl density, water molecules are promoted to quickly pass through, solutes such as salt are effectively intercepted, and high desalination rate is realized.

The invention belongs to the technical field of ion exchange membranes, and relates to a bipolar membrane and a preparation method thereof.The bipolar membrane comprises a cation exchange membrane, an anion exchange membrane and a middle layer; the cation exchange membrane is sulfonated polysulfone; the anion exchange membrane is aminated chloromethyl polysulfone; and the middle layer is prepared by reacting an organic amine compound with vinyl and chloromethyl polysulfone. The substrates of the three layers of polymers of the bipolar membrane are all made of polysulfone materials, the swelling characteristics of the materials are consistent, the affinity among the three layers is appropriate due to the fact that the three layers are made of the same material, the affinity among the layers of the bipolar membrane is easy to be tight, meanwhile, the stability of the middle catalyst layer is enhanced through a cross-linking method, and the stability of the middle catalyst layer is improved. The loss of the catalytic effect is prevented; the technical problem that the middle layer is prone to loss or blistering is solved.

The invention discloses a nanofiltration membrane continuous preparation method and a preparation system.The preparation method comprises the steps that a moving carrier membrane is evenly coated with a polymer solution, a membrane layer with the set thickness is formed, the carrier membrane is a polyester membrane or a polyether sulfone membrane, and the membrane layer is a membrane layer with the set thickness; the polymer solution is polysulfone, polyimide, polyacrylate or a mixture thereof; carrying out suction filtration on the membrane layer, and removing the solvent to form a nanofiltration membrane with a predetermined pore structure; the nanofiltration membrane is dried and coiled, and movement of the carrier membrane is achieved through traction of a nanofiltration membrane coiling mechanism. According to the preparation method and the preparation system, continuous automatic production of the nanofiltration membrane can be realized, related parameters in the production process can be automatically adjusted according to data detected in real time, the production efficiency is improved, the production cost is reduced, and the product quality consistency can be ensured.

The invention belongs to the technical field of porous adsorption membrane materials, and discloses a titanium lithium ion porous adsorption membrane material and a self-assembly preparation method and application thereof. The preparation method comprises the following steps: dissolving a film-forming polymer in a dispersion liquid containing MXene nanosheets to form a uniform precursor liquid; the MXene nanosheet is a transition metal carbide, nitride or carbonitride with a single-layer structure; dispersing a titanium-lithium composite oxide into the precursor solution to form a membrane casting solution; coating the membrane casting solution on a support body, and then performing phase inversion through pure water to obtain a matrix membrane; and placing the matrix membrane in a lithium eluent for immersion cleaning, replacing lithium ions in the matrix membrane, and carrying out a self-assembly reaction on the titanium-lithium composite oxide in the matrix membrane to obtain the titanium-based lithium ion porous adsorption membrane material. The MXene nanosheet and the polysulfone matrix membrane are innovatively introduced, the MXene nanosheet is fixed on the polysulfone matrix membrane to serve as an in-situ growth substrate of the titanium-lithium composite oxide, and the obtained membrane material has high adsorption capacity.

A method for preparing a 4,4'-dihydroxybiphenyl compound relates to a method for preparing an organic compound. The method uses 2,6-di-tert-butylphenol as a raw material and a new copper complex as a catalyst to efficiently generate 3,3',5,5'-tetra-tert-butylbiphenyl, which is de-tert-butylated to generate 4,4'-dihydroxybiphenyl. 4,4'-dihydroxybiphenyl is an important organic intermediate, often used as a rubber antioxidant and plastic antioxidant, for colorless vulcanized rubber products, rubber products for food packaging and medical latex products, and also for sulfur chloride cold vulcanized products, such as medical gloves. At the same time, it is also a dye intermediate and a stabilizer for petroleum products, such as a stabilizer for synthetic photosensitive materials and lubricating greases. In terms of synthetic polymers, due to its excellent heat resistance, it is often used as a modified monomer for polyesters, polyurethanes, polycarbonates, polysulfones and epoxy resins, etc., to manufacture excellent engineering plastics and composite materials.

The invention relates to the technical field of aluminum alloys, in particular to a high-strength corrosion-resistant aluminum material and a preparation method thereof. The preparation method comprises the following steps: mixing a chitosan corrosion inhibitor, an amino acid corrosion inhibitor, polysulfone, lignosulfonate and other raw materials to obtain a microcapsule corrosion inhibitor; and adding the microcapsule corrosion inhibitor into a dopamine solution, and carrying out stirring reaction to obtain the dopamine microcapsule corrosion inhibitor. Adding the dopamine microcapsule corrosion inhibitor and the curing agent into epoxy resin to obtain an epoxy resin coating; and the surface of the pretreated aluminum profile is coated with epoxy resin paint, and a finished product is obtained. The finished product prepared through the method has good corrosion resistance, durability and crack resistance, and therefore the finished product has wide application prospects in the technical field of aluminum alloy.

The invention relates to a reverse osmosis membrane and a preparation method thereof, and the preparation method comprises the following steps: immersing a polysulfone-based membrane into a dopamine-containing mixed solution, and carrying out constant-temperature oscillation to form a dopamine pretreatment layer so as to obtain a modified base membrane; dissolving rosmarinic acid ester modified m-phenylenediamine, piperazine, a surfactant, an auxiliary agent and a pH regulator in water, and stirring for dissolving to obtain a water phase solution; dissolving an acyl chloride monomer in an organic solvent, stirring and dissolving, then adding the modified titanium dioxide, and carrying out ultrasonic dispersion to obtain an oil phase solution; immersing the modified base membrane into the water phase solution, taking out the modified base membrane, immersing the modified base membrane into the oil phase solution, taking out the modified base membrane and drying the modified base membrane to obtain a pre-compounded reverse osmosis membrane; and carrying out post-treatment on the pre-compounded reverse osmosis membrane to obtain the reverse osmosis membrane. Under the condition that the water yield is guaranteed, the reverse osmosis membrane disclosed by the invention has a high desalination rate and the oxidation resistance of the reverse osmosis membrane is improved for a long time.

The application belongs to the technical field of porous adsorption membrane materials, and discloses a titanium lithium ion porous adsorption membrane material and a self-assembly preparation method and application thereof. The preparation method comprises the following steps: dissolving a film-forming polymer in a dispersion liquid containing MXene nanosheets to form a uniform precursor liquid; the MXene nanosheet is a carbide, nitride or carbonitride of a transition metal with a single-layer structure; dispersing a titanium lithium composite oxide in the precursor liquid to form a casting solution; coating the casting solution on a support, and then performing phase inversion by using pure water to obtain a matrix film; placing the matrix film in a lithium elution liquid for immersion washing, replacing lithium ions in the matrix film, and causing a self-assembly reaction of the titanium lithium composite oxide in the matrix film, so that the titanium lithium ion porous adsorption membrane material is obtained. The application innovatively introduces MXene nanosheets and a polysulfone matrix film, fixes the MXene nanosheets on the polysulfone matrix film as an in-situ growth substrate of the titanium lithium composite oxide, and the obtained membrane material has a high adsorption capacity.

The present invention relates to the technical field of separation membranes, and particularly relates to a preparation method for a selective permeable anti-pollution special separation membrane. In the solution, a supporting membrane is used as a substrate; the material of the supporting membrane is any one of polysulfone, polyethersulfone, polyimide, polyvinylidene fluoride and polyvinyl chloride; by subjecting a water phase reaction liquid A and an oil phase reaction liquid to an interfacial polymerization reaction on the surface of the supporting membrane, a polyamide layer is generated; by means of unreacted acyl chloride groups left on the surface, a water phase reaction liquid B is then poured onto the surface of the membrane to generate a secondary interfacial polymerization reaction; and by utilizing 3-bromopropionic acid, a quaternization treatment is carried out to obtain an anti-pollution special separation membrane, which has good selective permeability on a divalent / monovalent salt, a relatively high water flux, and improved antibacterial properties.

The invention discloses cyano-terminated modified polysulfone and a preparation method thereof. The terminal cyano group is selected from at least one of the following groups: n, m, p, q and r are independently 0 or 1; r1, R2, R3 and R4 are respectively and independently selected from any one of H, methyl, trifluoromethyl and cyano. Through molecular structure design, a polar group (cyano) with large dipole moment is introduced into the end group of polysulfone to prepare the cyano-terminated modified polysulfone and the film thereof. According to the polysulfone provided by the invention, the cyano group at the chain end has a relatively large degree of freedom, and when the cyano group is subjected to sub-Tg polarization, the steric hindrance is relatively small. Therefore, the cyano-terminated modified polysulfone can maintain relatively low dielectric loss and high Tg while increasing the dielectric constant.

The invention provides a preparation method of a multilayer reinforced alkaline water composite diaphragm. The preparation method comprises the following steps: S1, preparing raw materials; the raw materials comprise polysulfone, zirconium dioxide, polyethylene glycol, polyvinylpyrrolidone, potassium chloride, methyl pyrrolidone and a PEEK woven net; s2, preparing slurry; s3, preparing a film; the high-temperature alkaline electrolytic cell diaphragm has the beneficial effects that the PEEK woven mesh is adopted as the reinforced framework layer, the melting point of a PEEK material is 340 DEG C, the melting point of pps is about 280 DEG C, the heat resistance of the PEEK material is obviously higher than that of pps mesh cloth, and the heat resistance and safety of the diaphragm are greatly improved when the diaphragm is applied to a high-temperature alkaline electrolytic cell (greater than 100 DEG C) in the future.

A method for preparing a composite nanofiltration membrane based on aspartic acid modified carbon quantum dots belongs to the field of nanofiltration membrane preparation, and comprises the following steps: 1) dissolving citric acid monohydrate in water, adding aspartic acid, heating and stirring, and then adding a sodium hydroxide solution to adjust pH; (2) carrying out suction filtration on the mixed solution obtained in the step (1) by using a microfiltration membrane, dialyzing and purifying in ultrapure water, and freeze-drying to obtain the aspartic acid modified carbon quantum dots; (3) fixing a polysulfone base membrane in a mold, preparing a water-phase solution containing anhydrous piperazine and aspartic acid modified carbon quantum dots, pouring the water-phase solution into the mold to be in contact with the base membrane, and air-drying; and 4) preparing a trimesoyl chloride solution by using n-hexane as a solvent, pouring the trimesoyl chloride solution into a mold for contact, and finally drying to obtain the composite nanofiltration membrane.When the concentration of the aspartic acid modified carbon quantum dots is 2000ppm, the water flux reaches 168LMH, the retention rate reaches a peak value when the concentration of the quantum dots is 1000ppm and is 1.3 times of that of a base membrane, and the composite nanofiltration membrane shows excellent performance.

The invention discloses a polyolefin composition as well as a preparation method and application thereof, and belongs to the field of high polymer materials. According to the application, a specific amount of polysulfone resin is added into the polyolefin resin, so that the skid resistance and the dimensional stability of the polyolefin resin are improved; according to the present invention, the specific amount of the surfactant type antistatic agent is added so as to improve the antistatic property and the skid resistance, and the surfactant type antistatic agent and the polysulfone resin can synergistically improve the skid resistance, such that the obtained polyolefin composition has characteristics of high surface friction coefficient, good antistatic property and good dimensional stability, the material is suitable for products such as non-slip mats, wood-plastic floors, loose tubes and the like.

The invention discloses a hydrophobic gas diffusion electrode loaded with silver nanoparticles and application of the hydrophobic gas diffusion electrode in electrocatalytic carbon dioxide reduction, and belongs to the technical field of electrocatalysis. The hydrophobic gas diffusion electrode comprises a gas diffusion layer and a catalyst layer sprayed on the gas diffusion layer; the catalyst layer comprises a silver nanoparticle catalytic material, a first ionomer and a second ionomer; wherein the first ionomer is a fluororesin ionomer, and the second ionomer is a quaternized polysulfone ionomer. A system for preparing CO by reducing CO2 through electro-catalysis is constructed, the system comprises an MEA electrolytic cell, a cathode, an anode and an anion exchange membrane, and the cathode adopts the hydrophobic gas diffusion electrode loaded with the silver nanoparticles. The preparation method is mild in preparation condition and environmentally friendly, the modified hydrophobic gas diffusion electrode has high hydrophobicity, efficient conversion of CO2 can be achieved under the high current density, FECO can reach 96.5% under the high current density, and excellent catalytic performance is shown.