52results about How to "The film making method is simple" patented technology

The invention relates to a preparation method of a metal-organic framework material / polymer composite proton exchange membrane. The method is characterized by comprising the following steps: dissolving a polymer matrix and a certain amount of metal-organic framework material with an organic solvent and carrying out ultrasonic dispersion to form a uniform membrane liquid; coating the flat and smooth surface of a glass plate with the obtained membrane liquid, and then removing the organic solvent to obtain a composite membrane; and carrying out vacuum drying on the composite membrane for 24 hours to prepare the composite proton exchange membrane for an all-vanadium redox flow battery. The composite proton exchange membrane is smooth in surface; the internal structure of the membrane is regular; the membrane is uniform in thickness and free of a defect; and the thickness is 10-300 microns. The composite proton exchange membrane provided by the invention has excellent vanadium ion permeation blocking ability, keeps excellent proton transfer performance, overcomes the defect of relatively high vanadium ion permeability of an existing all-vanadium redox flow battery membrane, and has the advantages of being simple in preparation process, high in proton transmittance, excellent in vanadium blocking property, excellent in oxidative resistance, easy to industrially amplify and the like.

The invention discloses a high-performance Janus forward osmosis membrane, comprising a first surface of a super-hydrophilic polymer microporous membrane, a polymer membrane matrix intermediate layerand a second surface away from the first surface and coated with a super-hydrophobic inorganic nanoparticle coating, wherein the water droplet infiltration time of the first surface of the super-hydrophilic polymer microporous membrane is less than two seconds, and the second surface coated with the super-hydrophobic inorganic nanoparticle coating has a water droplet contact angle of greater than150 degrees. The Janus forward osmosis membrane has the advantage of high water flux and low-salt reverse diffusion flux.

The invention aims to improve the gas separation performance of a membrane material by means of blending modification to the membrane material and particularly provides a multilayer gas separation composite membrane having an ultrathin separation layer and a preparation method thereof. The membrane is mainly used for separating acidic gases, such as CO2 and the like. In the invention, the multilayer gas separation composite membrane is prepared with a block polymer Pebax and glycerol triacetate as the main material of a separation layer. The preparation method is simple and is easy to achieve large-scale production.

The invention discloses a novel polyvinyl alcohol nanofiltration membrane and a preparation method thereof. The method comprises the following steps: 1) mixing and dissolving ethylene glycol monomethyl ether and deionized water according to mass ratio of 1: 1 to prepare a solvent, respectively adding terephthalaldehyde and sodium dodecanesulphonate in the above solvent to prepare a mixing solution, heating the above mixing solution to the temperature of 60-65 DEG C, and stirring and dissolving the material to obtain a cross-linking agent solution; 2) dissolving the polyvinyl alcohol in deionized water to prepare an aqueous solution with mass fraction of 0.05-0.1%, heating the above aqueous solution to the temperature of 90-100 DEG C and stirring the material for 1.5 hours to prepare a polyvinyl alcohol aqueous solution; and 3) pouring the prepared cross-linking agent on a polysulfone base membrane, standing the material for 5 min and removing the superfluous solvent, placing the material in a baking oven at the temperature of 28 DEG C and drying the material; pouring the prepared polyvinyl alcohol aqueous solution on the surface of the membrane, and transferring the material into the baking oven and drying the material at the temperature of 60-90 DEG C for forming the membrane. The prepared polyvinyl alcohol nanofiltration membrane has high penetration selectivity and pollution-resistant performance, the method is easy to carry out, and a used modifier is easily available.

The invention relates to a corn bran based degradable antibacterial film and a preparation method thereof which is prepared from the following components by mass volume ratio: 4-9 percent of corn bran powder, 12-16 percent of sodium hydroxide, 3-5 percent of konjak gum, 1.0-1.6 percent of chitosan, 7.0-9.0 percent of acetic acid, 2-4 percent of arabic gum, 4-5 percent of allyl isothiocyanate and 10-15 percent of deionized water, wherein the corn bran powder selects 270-mesh corn bran powder. The corn bran based degradable antibacterial film has the thickness being 60-140 microns, the tensile strength being 35.9-46.7MP, the elongation at break being 21.6-30 percent and the folding endurance being 20-26 times. According to the corn bran based degradable antibacterial film, corn bran powder fine particles and antibacterial substances are uniformly distributed in a material, and a prepared packaging film has stronger mechanical properties and barrier property and can realize sealing with heating.

The invention relates to a preparation method for a proton-conducting membrane, and belongs to the technical field of ion exchange membranes. The preparation method is characterized in that dimethyl sulfoxide is adopted to dissolve polyvinylidene fluoride and sodium allylsulfonate monomer containing proton conducting functional group; a flow casting method is adopted to form a membrane on a smooth solid surface through flow casting; the sodium allylsulfonate monomer is initiated to carry out polyreaction; and the products of the polyreaction and polyvinylidene fluoride molecular chain are formed into the proton-conducting membrane of macromolecular interpenetrating network structure. The preparation method can obtain an ion exchange membrane material with ideal proton conductibility, and overcomes the disadvantage that the prior melting mould pressing process cannot prepare homogeneous phase ion exchange membranes; moreover, the preparation method has the advantages of simple technological process, easy industrial scaling up and the like.

The present invention is preparation process of reinforced hybrid organic-inorganic film and belongs to the field of organic-inorganic separating film preparing technology. During the preparation of the reinforced hybrid organic-inorganic film, inorganic precursor is added directly into filming liquid of organic polymer to obtain the mixture film casting liquid comprising organic polymer 10-20 wt%, additive 0-10 wt%, solvent 55-80 wt% and inorganic precursor 0-24 wt%; the film casting liquid is then cured at 25-75 deg.c for 1-2 days before flow casting or spinning; the flow cast or extruded filming liquid is pre-evaporated in the air for 0-120 s before curing in solidification bath in pH 0.4-4 or pH 10-13; and the cured film is further soaked in the solidification bath for 5-25 min and soaked in pure water for 1-2 days. The reinforced hybrid organic-inorganic film has simplified preparation process and high mechanical strength.

The invention relates to a preparation method of a metal-organic framework material / polymer composite proton exchange membrane. The method is characterized by comprising the following steps: dissolving a polymer matrix and a certain amount of metal-organic framework material with an organic solvent and carrying out ultrasonic dispersion to form a uniform membrane liquid; coating the flat and smooth surface of a glass plate with the obtained membrane liquid, and then removing the organic solvent to obtain a composite membrane; and carrying out vacuum drying on the composite membrane for 24 hours to prepare the composite proton exchange membrane for an all-vanadium redox flow battery. The composite proton exchange membrane is smooth in surface; the internal structure of the membrane is regular; the membrane is uniform in thickness and free of a defect; and the thickness is 10-300 microns. The composite proton exchange membrane provided by the invention has excellent vanadium ion permeation blocking ability, keeps excellent proton transfer performance, overcomes the defect of relatively high vanadium ion permeability of an existing all-vanadium redox flow battery membrane, and has the advantages of being simple in preparation process, high in proton transmittance, excellent in vanadium blocking property, excellent in oxidative resistance, easy to industrially amplify and the like.

The invention relates to an ion exchange membrane of interpenetrating network structure and a preparation method thereof. The preparation method is characterized by dissolving a hydrogen type perfluorosulfonic acid ion exchange resin and a salt type perfluorosulfonic acid ion exchange resin with a polar organic solvent; casting the solution on the smooth solid surface; and then forming the membrane under heating condition, wherein the molecular chains of the hydrogen type perfluorosulfonic acid ion exchange resin and the salt type perfluorosulfonic acid ion exchange resin form the macromolecular ion exchange membrane of interpenetrating network structure. The ion exchange membrane with good mechanical performance can be obtained by the method, thus overcoming the defect that the homogeneous crosslinked ion exchange membranes can not be prepared in the existing fusing and molding processes, and the method has the advantages of simple technological process, easy industrial scale-up, etc.

The invention discloses a method for preparing high-density polyethylene / ethylene-vinyl acetate blended hydrophobic microporous membranes. The method is characterized in that the high-density polyethylene / ethylene-vinyl acetate blended hydrophobic microporous membranes comprise, by weight, 10-50 parts of high-density polyethylene, 1-30 parts of ethylene-vinyl acetate, 50-80 parts of diluents and 0-4 parts of nucleating agents. The method for preparing the high-density polyethylene / ethylene-vinyl acetate blended hydrophobic microporous membranes which are blended membranes is a thermally induced phase separation method. The method has the advantages that obvious modification effects can be realized for the blended membranes under the condition that the excellent chemical properties and thehigh strength of the high-density polyethylene are not changed; the mechanical performance of the membranes which are products can be greatly enhanced, and the membranes are excellent in flexibility,high in breaking elongation and long in service life; the ethylene-vinyl acetate is added, accordingly, the membrane pore sizes are narrow and uniform in distribution, the pore sizes and the porosityare easy to control, the pore sizes range from 0.1 micrometer to 1 micrometer, and the porosity is higher than 62%; the heat conductivity coefficients of the membranes which are the products can be lowered, the method can be applied to membrane distillation procedures, accordingly, the temperature difference of two sides of each membrane and the vapor pressure difference can be increased, heat loss can be reduced, and the heat efficiency can be improved.

The invention discloses a method for preparing a nanofiber-based composite nanofiltration membrane by low-temperature reverse interface polymerization, which is characterized in that it comprises: electrospinning a polymer solution to obtain a nanofiber non-woven fabric, which is obtained after cold pressing The nanofiber porous base membrane; the surface of the nanofiber porous base membrane is infiltrated with a low-temperature oil phase monomer solution; then the water phase monomer solution is added for reverse interfacial polymerization reaction; the nanofiber base composite nanofiltration membrane is obtained after heat treatment. The invention reduces the volatilization rate of the oil phase under low temperature conditions by controlling the temperature of the oil phase solution, provides a complete and uniform reaction interface for the reverse interface polymerization, and overcomes the skin layer inherent in the reverse interface polymerization caused by the rapid volatilization of the oil phase Defects and infiltration problems, the thickness, uniformity and density of the functional barrier layer are optimized by controlling the temperature of the oil phase solution and the polymerization parameters of the reverse interface, thereby enhancing the nanofiltration performance of the composite membrane.

The invention discloses a super hydrophobic modification method for polyvinylidene fluoride hydrophobic membranes and belongs to the technical field of membrane separation. The method comprises: preparing membrane casting solution by using polyvinylidene fluoride (PVDF), N,N-dimethylacetamide (DMAC) serving as a solvent and non-solvent low-molecular-weight alcohol and aging the membrane casting solution to form upper membrane solution; preparing membrane casting solution by using PVDF, DMAC, LiCl or / and polyvinyl pyrrolidone (PVP), and aging the membrane casting solution to form lower membrane solution, wherein the PVDF content in the lower membrane solution is higher than that in the upper membrane solution; scraping the lower membrane solution and the upper membrane solution on a glass plate in turn, and placing the glass plate in air at 50 to 75 DEG C and at a water relative humidity of 80 to 100 percent to obtain a primary ecological membrane; and immersing in running water for stripping the membrane and drying to obtain a polyvinylidene fluoride composite film of which the surface is super hydrophobic. In the invention, the method is simple, the process flow is short, the cost is low, and the prepared membrane has high flux and high salt rejection rate.

The invention relates to a carbon dioxide separating membrane having both primary amine and carbonate and a preparation method thereof; the method comprises the steps of preparing the polymer blends of poly (vinyl amine-diallyl dimethyl ammonium carbonate) copolymer and polyvinyl amine or poly diallyl dimethyl ammonium carbonate; taking polysulfone ultrafiltration membrane as a supporting body, dissolving the polymer blends into deionized water, and defoaming to obtain coating solution after stirring; under the condition of a certain temperature and relative humidity, carrying out drying treatment for a period of time to obtain the CO2 separating membrane having both the primary amine and the carbonate. The carbon dioxide separating membrane having both the primary amine and the carbonate realizes the synergic coupling effect between different function carriers: not only is the efficiency of the function carriers strengthened, but also the defects of various function carriers are avoided when the carriers are used alone. The carbon dioxide separating membrane having both the primary amine and the carbonate has excellent CO2 permeation selection performance: with regard to the mixed gas of CO2 / N2, under the condition that the feed pressure force is 0.11-2.00 MPa, the permeation rate of the CO2 is (137-1842)*10-6, and the CO2 / N2 separation factors are 23-160.

The invention discloses a composite flat-sheet polysulfone membrane doped with active carbon and nanometer zinc oxide and a preparation method. The preparation steps are as follows: mixing nanometer zinc oxide, active carbon particles, polysulfone and 1-methyl-2-pyrrolidone in a mass ratio of (0.5-1) to 5 to 20 to 100; ultrasonically oscillating and dispersing the components; stirring the mixture until the components are completely dissolved, de-foamed and membrane-pushed; standing the pushed membrane in the air for 15-20 seconds, then soaking the membrane to a water coagulating bath for 20 minutes, putting the soaked membrane to deionized water to soak for 3 days and then taking out the soaked membrane. The composite flat-sheet polysulfone membrane provided by the invention can improve anti-pollution and adsorption performances of the membrane, and further can carry out photocatalysis under ultraviolet irradiation to effectively remove degradation-resistant pollutants in the water.

The invention relates to a carbon dioxide separation membrane with primary amino groups and carbonate groups and a preparation method thereof; preparation of poly(vinylamine-diallyl dimethyl ammonium carbonate) copolymer and polyvinylamine or polydiallyl A blend of dimethyl ammonium carbonate; with polysulfone ultrafiltration membrane as a support, the blend is dissolved in deionized water, stirred and defoamed to obtain a coating solution; dried for a period of time under certain temperature and relative humidity conditions to obtain A CO2 separation membrane with both primary amine groups and carbonate groups. The invention realizes the synergistic coupling effect between different functional carriers: not only the efficiency of the functional carriers is enhanced, but also the disadvantages of various functional carriers when used alone are avoided. Excellent CO2 permeation selectivity performance: For CO2 / N2 mixed gas, under the feed gas pressure of 0.11-2.00MPa, the CO2 permeation rate is (137-1842)×10-6, and the CO2 / N2 separation factor is 23-160 .

The invention discloses a method for preparing a charged nanofiltration membrane by chloromethylated polysulfone. According to the invention, chloromethylated polysulfone is placed in a trimethylamine solution to obtain a positively charged polysulfone material, then the material is subjected to magnetic stirring for 24 h, the positively charged polysulfone material is placed in ethylene glycol monomethyl ether to prepare a casting solution, the casting solution is used for coating the surface of a polysulfone ultrafiltration base membrane, and the base membrane is dried in a temperature scope of 30-40 DEG C to prepare the nanofiltration membrane; under pressure of 1.2 MPa, the nanofiltration membrane has retention rate and flux on sodium chloride and magnesium chloride being 69.3% / 52.6 L.m<-2>.h<-1> and 76.8% / 40.6 L.m<-2>.h<-1>. The film forming material contains a positively charged group, the retention rate of a positively charged dye by the membrane can reach 95% and above, the charged nanofiltration membrane can be used for separating the salt and the positively charged dye, the nanofiltration membrane has the hydrophilic group, and has good anti-pollution performance.

The invention provides a preparation method for separating phenolic organic matter / water thermoplastic pervaporation polymer membrane. Through the synergistic effect of solvent ratio, temperature and solvent volatilization rate, the curing rate of thermoplastic materials is regulated, and pervaporation polymer films with excellent film-forming properties are prepared. The pervaporation polymer membrane prepared by the method has outstanding separation performance in removing phenolic organic matter in water, and its flux and separation factor are superior to the similar separation membranes prepared by the traditional method. The method can better retain the intrinsic properties of the membrane material and maximize the performance of the separation membrane.