138results about How to "Simple film making process" patented technology

The present invention discloses preparation process of hydrophilic modified hollow microporous polyethylene film. Some hydrophilic matters with relatively high surface energy are used to mix with fused polyethylene. The present invention features that the prepared hollow microporous polyethylene film has improved hydrophilicity, including contact angle reduced by over 20 deg, film porosity of 40-80 %, average pore size of 0.1-0.5 micron and air permeability of 0.01-1 cu cm/sq cm.s.cmHg. The film has inner diameter of 250-500 microns and thickness of 30-60 microns. The prepared hollow microporous polyethylene film of the present invention has average pore size, porosity and hydrophilicity much higher than those of hollow polyethylene fiber film prepared through fusion spinning-stretching process, and has no obvious change in tension strength, rebound degree, etc.

A gasifying osmotic film for separating the azeotropic methanol/dimethyl carbonate solution is prepared from polyvinyl alcohol and polyacrylic acid. Its preparing process is also disclosed.

The invention discloses a polyamide film composite membrane and a preparation method and application thereof. The composite membrane comprises a polymer support layer and a polyamide active layer. The polyamide active layer is obtained by a reaction of a multielement acyl chloride solution and a polyamine aqueous solution containing a tertiary amine additive. In the preparation process, the polyamine aqueous solution containing the tertiary amine additive and the multielement acyl chloride solution undergo an interfacial polymerization reaction to produce the modified polyamide active layer so that the film-forming process is greatly simplified. The composite membrane has a high crosslinking degree and high compactness, and has a high water flux in membrane separation, a low reverse salt flux and good anti-fouling properties.

The invention discloses a high permeability nanofiltration membrane containing zwitterion and a preparation method. The nanofiltration membrane is composed of a polysulfones supporting layer and a functional layer containing a terpolymer of zwitterion group; the preparation process comprises the following steps: acquiring the water-soluble terpolymer through free radical copolymerization reactioncontaining zwitterion, preparing the copolymer and a cross-linking agent to an aqueous solution with a certain concentration, dipping one layer of the aqueous solution on the surface of the polysulfones supporting layer, then solidifying to obtain the membrane. The water flux of the nanofiltration membrane containing zwitterion is 30-45L.m-2.h-1 under the operation pressure of 0.6 MPa, and the nanofiltration membrane has high retention rate to bivalent ions with the highest of 97.5%, the retention rate to the monovalent cation is lower than 60%. The prepared nanofiltration membrane containingzwitterion has high permeability and stain resistane, the method for preparing the membrane is simple and easy which has low cost, and has good industrialization application prospect.

The invention relates to a preparation method of a pervaporation film with the preferential penetration of dimethyl carbonate. Film casting liquid containing vinyl polydimethylsiloxane (Vi-PDMS), hydrogen-containing polydimethylsiloxane (H-PDMS), hydrophobic nano SiO2, a catalyst and a solvent is adopted, a film is coated on an upper layer of a porous ultrafiltration film supported by a polyester non-woven fabric, is aired at room temperature and is also heated, and the cross linkage of the film is finished. An additive type polydimethylsiloxane compound film filled with the hydrophobic nano SiO2, which is obtained by the preparation method of the pervaporation film with the preferential penetration of the dimethyl carbonate, has a simple film preparation process, adopts the materials with low price, strong swelling resistance in dimethyl carbonate/methanol azeotropic liquid, and excellent performance of preferential penetration of the dimethyl carbonate. When the filling mass proportion of the hydrophobic nano SiO2 is 15 percent, the separation factor alpha of the pervaporation film is equal to 3.97, and the penetration flux J is equal to 0.707kg/m2h ([DMC]=30wt%, 40 DEG C).

A cellulose hollow fiber ultrafiltration membrane with figure-type hole support layer dissymmetrical structure; the process is: 1) mixing, solving and debubbling the NMMO .H2O 88-93wt% with and fiber in 95DEG C to prepare uniform casting film solution which cellulose concentration is 7-12wt%; 2) weaving the residual solvent in films; 4) plasticizing it with 30% -50% glycerol and preparing the wet hollow film. Compared with traditional renewable and modified cellulose film, the crystallinity, mechanical strength, the capabilities of resistance organic solvents, alkali and acid of the hollow film is good, the anti-pollution capability is stronger, and the water treatment prospect is good.

The method of sputtering and depositing bioactive gradient hydroxyapatite/Ti layer on Ti alloy surface includes the following steps: mixing and ball milling material powder; hydrothermal reaction; stoving and grinding; mixing target material; cold pressing at 200-300 MPa to form; sintering; double-inclined target sputtering; and heat treatment of the sputtered film. The product has multilayer structure of Ti alloy matrix, compact transition TiO2 layer I with dispersed hydroxyapatite, TiO2 reinforced transition hydroxyapatite layer II, and porous hydroxyapatite layer. The present invention realizes the double gradient of both component and structure, and raises the interface binding strength effectively. The present invention has simple film preparing process and homogeneous film thickness, is suitable for surface activation of implant with complicated shape, and can prepare hard tissue for clinical need, especially as bearing bone repairing and substituting material.

The invention discloses a preparation method of a polyester fiber braided tube enhanced type composite hollow fiber forward osmotic membrane. The preparation method comprises the following steps of confecting a polymer, an organic additive, an inorganic additive and an organic solvent to be homogeneous membrane casting liquid according to a proportion; uniformly coating the membrane casting liquid on the outer wall and an internal pore canal of a polyester fiber braided tube, so as to obtain a braided tube of which the inner wall and the outer wall are coated with membranes; making the membrane coated braided tube pass a certain air residence time and then enter a coagulation bath to carry out phase-inversion membrane formation; soaking a primarily formed membrane in deionized water to remove the residual organic solvent, soaking the primarily formed membrane in a hot water bath, finally, soaking the primarily formed membrane in a glycerol aqueous solution, and then taking out and airing the primarily formed membrane, so that the polyester fiber braided tube enhanced type composite hollow fiber forward osmotic membrane is made. According to the preparation method, polymer membrane casting liquid is coated on the inner wall and the outer wall of the braided tube in a one-step manner by adopting an immersion precipitation phase inversion method to obtain a high-strength composite hollow fiber forward osmotic membrane; the film making process is simple; the water flux, the selectivity, the hydrophilism, the performance stability and the service life of a membrane are improved by an organic and inorganic blending membrane making method.

The hollow cellulose fiber gas humidifying membrane is homogeneous compact structure prepared through direct dissolving cellulose with N-methyl morpholine monohydrate as solvent and spinning vian immersing phase converting process. The preparation process includes: dissolving cellulose with 80-93 % concentration MMNO.H2O at 80-110 deg.c and debubbling to obtain membrane forming liquid of 7-20 wt% cellulose concentration; spinning hollow membrane through immersing phase converting process; washing to eliminate residual solvent in the membrane; and drying naturally to obtain dry hollow membrane. The cellulose fiber gas humidifying membrane thus prepared has high crystallization degree, high mechanical strength, high organic solvent, acid and alkali resistance, high water penetrating capacity, and small oxygen and hydrogen osmosing coefficient, and is very suitable for use in gas humidifying system in fuel cell.

A gas separating film of hollow fibers from cellulose and its preparation. The film has an even and compact texture. Solving cellulose directly by the aqueous solution of methyl morpholine oxide, spinning hollow fibers of cellulose by an immersing phase conversion method. The preparation method is:1) mixing 80í½93úÑ of MMNOíñH2O by weight with cellulose, and debubbling, obtaining a transparent casting-film solution containing 7í½20úÑ of cellulose by weight;2) spinning hollow fibers by an immersing phase conversion method;3) wash off residual solvent in the film; 4) drying naturally with the relative humidity of 40úÑí½90úÑ, getting dried hollow film. Compared with traditional regenerative and modified cellulose films, the hollow film is better in crystallization, mechanical strength, capacities of resisting organic solvents, acids and bases, and has great performance in penetrating and separating gases, especially adapts to separate and recycle acidic gases such as CO2 and SO2.

The invention discloses a zeolite imidazate-doped polyether block amide (PEBA) gas separation membrane, and a preparation method and application thereof. According to the preparation method provided by the invention, two inorganic nano-materials, i.e. ZIF-8 and Zn/Ni-ZIF-8 are successfully prepared and are mixed and stirred with polyether block amide at 40 to 80 DEG C, and a ZIF-8-PEBA and Zn/Ni-ZIF-8-PEBA mixed matrix membrane is prepared through a dry phase transformation method. The zeolite imidazate-doped polyether block amide gas separation membrane, and the preparation method and the application thereof provided by the invention have the advantages that the preparation method of the inorganic materials is simple, the conditions are mild, the operation is easy, and the inorganic material is environmentally friendly; the prepared membrane is acid and alkali resistant and good in flexibility; the membrane has excellent comprehensive performance when being used for gas separation; particularly, the Zn/Ni-ZIF-8-PEBA mixed matrix membrane with the adding content being 10 percent by weight has high CO2 permeation flux and CO2/N2 selectivity.

The invention discloses a preparation method of a polyethylene imine/sodium lignin sulfonate composite membrane. The preparation method includes: using a polysulfone ultrafiltration membrane with an electronegative surface as the base membrane, polyethylene imine and sodium lignin sulfonate are sequentially self-assembled to the base membrane to form a self-assembled composite layer, and the self-assembled composite layer is allowed to form a structurally-stable composite layer through glutaraldehyde crosslinking. The preparation method has the advantages that the electrostatic interaction among electrolyte with different charges is utilized to allow cation and anion polyelectrolyte to attach to the surface of the polysulfone ultrafiltration membrane, and layer-by-layer self-assembling of the polyelectrolyte is achieved; when the number of polyelectrolyte double-layers is 7, and composite nanofiltration membrane has good separation performance.

The invention discloses a dimethylpolysiloxane composite membrane and a preparation method and application thereof, and belongs to the field of membrane separation. The dimethylpolysiloxane compositemembrane comprises a mixed substrate layer, the mixed substrate layer is a membrane which is formed by porous hybrid material doped dimethylpolysiloxane after the dimethylpolysiloxane is cured, a porous hybrid material is the hybrid material of a metal organic framework material and a carboxyl group modified carbon material, and the metal organic framework material is connected with the carboxyl group modified carbon material through hydrogen bonds. The dimethylpolysiloxane composite membrane comprises a supporting layer, any of the surfaces of the supporting layer is coated with the mixed substrate layer, the supporting layer is a polymeric membrane, the supporting layer is non-woven fabric or the supporting layer is non-woven fabric which is coated with the polymeric membrane. Accordingto the dimethylpolysiloxane composite membrane, the composite membrane is prepared through a solution blending method, a membrane preparation technology is greatly simplified, inorganic particle aggregation is not caused, and the content of organic solvent separation factors of the obtained composite membrane is high.

The invention relates to a method for preparing a macromolecular ultrafiltration membrane. The method for preparing a low trapped molecular weight hollow fibre ultrafiltration membrane comprises the following steps: (1) preparation of a casting membrane liquid: the method uses polysulfone as a raw material, dimethylfomamide or dimethylacetamide as a solvent and polyvinylpyrrolidone as an additive to prepare the casting membrane liquid, wherein each composition has the following mass percentage: 15 to 40 percent of the polysulfone, 50 to 80 percent of the dimethylfomamide or dimethylacetamide and 5 to 20 percent of the polyvinylpyrrolidone; and the casting membrane liquid is heated and stirred at a temperature of between 30 and 80 DEG C so that each composition is fully dissolved, sealed, kept stand and defoamed; (2) membrane forming: the casting membrane liquid prepared in the step (1) passes through a spinning plate, injected to a heating water bath through the distance of an air section and condensed to form the hollow fibre ultrafiltration membrane; and (3) posttreatment: the hollow fibre ultrafiltration membrane prepared in the step (2) is soaked in a mixed solution of glycerin, Tween-80 and water.

The invention relates to a composite carbon diaphragm with a mesoporous and microporous gradient structure and a preparation method for the diaphragm. The composite carbon diaphragm with the mesoporous and microporous gradient structure consists of a porous support body, a mesoporous intermediate layer and a surface separation layer, and is characterized in that the pore diameter of the porous support body is 100 to 500 nanometers, the breaking strength is 2 to 15MPa, and the anti-explosion strength is 3 to 10MPa; the pore diameter of the mesoporous intermediate layer is 2 to 10 nanometers, the specific surface area is 400 to 1,000 m<2>/g, the porosity is 30 to 50 percent, and the thickness is 1 to 10 micrometers; and the pore diameter of the surface separation layer is 0.3 to 0.5 nanometer, the specific surface area is 300 to 600 m<2>/g, the porosity is 20 to 40 percent, and the thickness is 0.1 to 5 micrometers. By the composite carbon diaphragm with the mesoporous and microporous gradient structure, the phenomenon that the gas separation performance of the composite carbon diaphragm is greatly reduced due to the defect of the surface of the support body is avoided, and the permeability of the prepared composite carbon diaphragm is improved obviously on the basis of keeping high gas separation selectivity.

The invention relates to a preparation method of a positively charged nanofiltration membrane. The preparation method comprises the steps of preparation of a pretreatment base membrane, preparation of a coating solution, coating and solidifying. The positively charged nanofiltration membrane has good stability and leaching resistance. According to the preparation method, the charge performance and the hydrophilic-hydrophobic property of the positively charged nanofiltration membrane can be improved through adjusting components and proportions of a copolymer monomer and the water flux of the positively charged nanofiltration membrane can be effectively improved. The preparation method of the positively charged nanofiltration membrane is simple, the production cost is low, the used functional polymer material is simple and available and has a good industrial application prospect.