87results about How to "Small degree of swelling" patented technology

The invention discloses a nano-compound adsorbent for efficiently removing trace phosphorus, arsenic and antimony from a water body, belonging to the technical field of environment functional materials. The organic framework of the nano-compound adsorbent of the invention is hypercrosslinked styrene-divinylbenzene ion exchange resin, a functional group for surface binding of the organic framework is a quaternary ammonium group or pyridyl, nano-inorganic functional particles are loaded, and the total volume of 1-20nm nano-pores accounts for greater than or equal to 90% of the total volume of all the pores of the organic framework. The nano-inorganic functional particles are nano-hydrated ferric oxide or nano-hydrated manganese oxide. The nano-compound adsorbent of the invention has more obvious nano effect, strong reaction activity, great adsorption capacity and high selectivity, well solves the defects of obvious swelling, weak adsorption reaction activity, small adsorption capacity, lower adsorption selectivity and the like of the existing nano-compound adsorbent, and is more suitable for advanced treatment of micro-pollution of water and waste water.

The invention discloses a preparation method of a salt-resistant and detergent-resistant seaweed fiber; by introducing an auxiliary agent containing a borate radical, a finished product seaweed fiber is contacted and infiltrated with an auxiliary agent solution, appropriate raw materials, proportion and reaction conditions are selected, and thus the salt-resistant and detergent-resistant seaweed fiber is prepared. The preparation method solves the problems that the seaweed fiber and textiles thereof are not resistant to salts and detergents; the seaweed fiber after being modified by the borate radical and textiles thereof have good salt resistance and can withstand washing of alkaline detergents; the seaweed fiber modified by the auxiliary agent solution enables the swelling degree to be reduced to 39.8% after being soaked for 72 h in 30 DEG C normal saline, and enables the swelling degree to be reduced to 55.3% after being soaked for 24 h in a standard detergent; and the original appearance of the fiber is maintained, no obvious dissolution phenomenon generates, and at the same time, the self flame retardant performance of the seaweed fiber can be maintained.

A polymer ultraviolet-pH response p(AA-co-AAAB) copolymer aqueous gel is prepared by synthesizing molecular chain containing azobenzol group intermediate monomer AAAB and preparing p(AA-co-AAAB) copolymer aqueous gel by it. It has stable deformation and excellent ultraviolet response. It can be used for miniature optical devices, optical switches and sensors.

The invention discloses a preparation method of a semi-flexible polyether sulfone/ ketone anion-exchange membrane, and particularly provides a preparation method of a high-conductivity anion-exchange membrane of a fuel cell. The membrane material contains flexible aliphatic chains with different lengths in repetitive units. The preparation method comprises steps as follows: 1), polymer synthesis; 2), polymer halomethylation; 3), preparation of the semi-flexible polyether sulfone/ ketone anion-exchange membrane. Due to the fact that the aliphatic chains are introduced into a main polymer chain, the flexibility of the main chain is further improved, the main chain acquires higher mobility, hydrophilic and hydrophobic microphase separation is enhanced, a better ion channel is formed accordingly, and membrane swelling is reduced. The preparation technology is simple, the cost is low, and the prepared anion-exchange membrane has high conductivity and good stability and is applicable to an alkaline fuel cell.

The invention discloses a preparation method of a drought-resistant water-retaining agent, and belongs to the technical field of soil fertilizers and water-saving agriculture. According to the preparation method provided by the invention, N, N-methylene bisacrylamide is used as a crosslinking agent, potassium persulfate is used as an initiator, carboxymethyl cellulose is subjected to graft copolymerization with acrylic acid and acrylamide, so that the number of space network crosslinking points is further increased; after being effectively grafted with hydrophilic monomers acrylic acid and acrylamide, a large network structure can be formed, liquid can be better absorbed and retained, the water holding capacity of soil can be increased, the moisture evaporation rate of the soil can be reduced, and modified montmorillonite is added at the same time, and because montmorillonite bentonite has the characteristics of relatively high cohesiveness, cation exchange property, hygroscopicity andthe like, the characteristics have good effects of adjusting physical and chemical properties of the soil and improving water, fertilizer and gas heat of the soil. The preparation method provided bythe invention solves the problems that an existing soil drought-resistant and water-retaining agent can cause soil hardening and the drought-resistant and water-retaining capacity of the soil is not high when used in the soil for a long time.

The invention relates to a high-temperature water environment resistant tetrapropyl fluoro elastomer composition and a preparation method thereof, and belongs to the field of rubber materials. The high-temperature water environment resistant tetrapropyl fluoro elastomer composition comprises the following components in parts by weight: 100 parts of tetrapropyl fluoro elastomer, 1-6 parts of a processing aid, 1-8 parts of organic peroxide, 15-80 parts of a reinforcing filler, 2-6 parts of an auxiliary crosslinking agent and 3-25 parts of a high-temperature stabilizer. After the tetrapropyl fluoro elastomer composition materail is aged for 24 hours in a high-temperature water environment at the temperature of 350 DEG C, the hardness, the tensile strength and the elongation retention rate ofthe tetrapropyl fluoro elastomer composition material are obviously higher than those of rubber without a high-temperature stabilizer, and the volume retention rate is close to 90%. The tetrapropyl fluoro elastomer material resisting corrosion of the high-temperature water environment can be used as a main material of a rubber barrel of a thermal recovery packer, so that the thermal recovery packer with better performance is formed and applied to heavy oil recovery at home and abroad, and the high-temperature water environment resistant tetrapropyl fluoro elastomer composition has wide application prospect.

The invention relates to a high-temperature crosslinked chitosan/nitrogenous phosphonic acid polysiloxane proton exchange membrane and a preparation method thereof. The membrane is obtained by the following steps: (1) preparing a chitosan liquid; (2) preparing an organic nitrogenous phosphonic acid liquid; (3) slowly dropwise adding the organic nitrogenous phosphonic acid liquid to the chitosan liquid, fully stirring evenly to obtain a mixed liquid, and slowly dropwise adding amino siloxane to the mixed liquid, so as to obtain a sol liquid; (4) slowly adding an aldehyde crosslinking agent to the sol liquid, and stirring evenly, so as to obtain a gel liquid; and (5) pouring the gel liquid into a polytetrafluoroethylene mold, ageing at a room temperature for 2-3 days, drying at 80 DEG C, then sequentially carrying out heat treatment at 100 DEG C, 120 DEG C and 150 DEG C for 2 hours respectively, cooling and stripping off from the polytetrafluoroethylene mold, so as to obtain the high-temperature crosslinked chitosan/nitrogenous phosphonic acid polysiloxane proton exchange membrane. The preparation method is simple, and mild in reaction condition; the prepared proton exchange membrane has the advantages of relatively high proton conductivity and good heat stability under high-temperature and anhydrous conditions.

The invention discloses a preparation method of three-dimensional carrageenan/sodium alginate double network structure gel spheres. The method comprises the following steps: respectively taking carrageenan and sodium alginate, adding deionized water, and performing uniform mixing to form a carrageenan and sodium alginate mixture; dropwise adding the carrageenan and sodium alginate mixture into a K<+> solution, and soaking obtained drops for 4-8 h to obtain gel spheres; soaking the gel spheres in a Ca<2+> solution for 8 h, and then soaking and washing the gel spheres with deionized water to obtain hydrogel; and freeze-drying the hydrogel to obtain the target gel spheres. The product prepared in the invention has the advantages of simple preparation process, easiness in control of conditions, low cost, small rupture possibility in the swelling process, excellent adsorption property and excellent mechanical properties.

The invention relates to a preparation method of a proton exchange membrane used in fuel cells. The invention specifically relates to a preparation method of a cross-linked polyphenyl ether composite proton exchange membrane. According to the method, polyphenyl ether is dissolved in a chlorobenzene solution, such that a high-molecular solution is prepared; gamma-mercaptopropyl triethoxysilane or gamma-mercaptopropyl trimethoxysilane is added; the mixture is heated and stirred such that a solution is formed; the solution is cast on a glass plate and is dried and cross-linked, such that a membrane is formed; the cross-linked polyphenyl ether composite membrane is soaked and oxidized in a hydrogen peroxide solution under room temperature, such that the cross-linked polyphenyl ether composite proton exchange membrane is obtained. The composite proton exchange membrane provided by the invention has excellent proton conductivity, wherein the proton conduction rate is higher than that of a Nafion membrane. The membrane provided by the invention also has good stability. A swelling degree of the membrane provided by the invention is smaller than that of the Nafion membrane. The method provided by the invention also has the advantages of simple process and convenient operation. A membrane production cost is lower than that of the Nafion membrane. The method is suitable for industrialization.

The invention discloses a preparation method of a phosphotungstic acid/polyvinyl alcohol composite proton exchange membrane, belonging to the field of fuel-cell electrolyte materials. The method comprises the following steps: firstly, dissolving polyvinyl alcohol in de-ionized water to prepare a polymer solution; adding phosphoric acid and sodium tungstate, heating and stirring to form a solution; pouring the solution on a polytetrafluoroethylene glass plate; and drying to form a membrane, so as to obtain a phosphotungstic acid/polyvinyl alcohol composite proton exchange membrane. The composite proton exchange membrane prepared according to the preparation method provided by invention not only has the characteristics of excellent proton electrical conductivity, low methanol permeability and low cost, but also can be conveniently produced in a large scale.

The invention relates to a method for using alginic acid-calcium carbonate hybrid gel to immobilize beta-glucuronidase, wherein, calcium carbonate powdered precipitation is generated by mixing and stirring sodium carbonate solution and calcium chloride solution at room temperature, and then kept, washed by water and acetones and dried, and micron mesoporous calcium carbonate particles are obtained which are added into trihydroxymethyl aminomethane-hydrochloric acid (Tirs-HCl) buffer of beta-glucuronidase or aqueous solution thereof for absorption, and calcium carbonate particles absorbing glucuronidase are obtained after centrifugal separation, then uniformly mixed with sodium alginate solution and added into calcium chloride solution by dropping for aging. The invention has the advantages of mild preparation conditions, simple and easy preparation technologies, good immobilization ability of obtained hybrid vectors on enzymes, low leakage rate of immobilized beta-glucuronidase, low swelling capacity and good reusage stability.

The invention discloses an alcohol dehydrogenase embedded gelatin-silica hybrid gel and a preparation method thereof. According to invention, the grain diameter of the alcohol dehydrogenase embedded gelatin-silica hybrid gel is 3-4mm, and a silica coating is coated on a gelatin core. The preparation method comprises the following steps of: preparing a mixed solution of gelatin and alcohol dehydrogenase; preparing a mixed solution of sodium silicate and a glutaraldehyde solution precursor; adding the mixed solution of gelatin and alcohol dehydrogenase into deionized water at a temperature of 0-4 DEG C droplet by droplet to generate alcohol dehydrogenase embedded gelatin gel particles; stirring and incubating to obtain the alcohol dehydrogenase embedded gelatin-silica hybrid gel. The preparation method has the advantages that the preparation condition is mild, the preparation process is simple and feasible, and the alcohol dehydrogenase embedded gelatin-silica hybrid gel has a strong fixing capability; compared with gelatin gel, the hybrid gel has a lower leakage rate of immobilized alcohol dehydrogenase, and lower swelling degree and better recycling stability.

The present invention provides a preparation method of an anion exchange membrane capable of introducing surfactant molecules to be used as cationic sites, and belongs to the technical field of fuel cells. The method comprises the following steps: using quaternized chitosan as a main membrane raw material and acetic acid solution as a solvent, introducing conductive materials Gemini molecules (G16-2-16, G12-2-12, G8-2-8) of three different molecular structures into a membrane structure, initiating polymerization to form a high polymer long chain by an initiator KPS, and adding a crosslinking agent GA to crosslink the membrane into a mesh structure; and casting the membrane on a glass plate by using a tape casting method, and penetrating the dried membrane into a potassium hydroxide solution to prepare a hydroxyl ion type compound membrane. The anion exchange membrane prepared by the preparation method has higher electrical conductivity and a lower swelling degree. According to the preparation method, the problems of a pure QCS anion membrane such as low electrical conductivity and high degree of swelling are solved.

The invention relates to a polysulfone modification based anionic membrane having ultralow aqueous solution swelling degree for a fuel cell and a preparation method of the anionic membrane, belonging to the technical field of fuel cells. The preparation method comprises the following steps of completely dissolving polysulfone (PSF) particles having rigid macromolecule skeleton structures as a membrane base solution by taking chloroform as a solvent; uniformly doping conductive material Gemini molecules {diethyl maleate di[dimethyl dodecyl]ammonia/ammonium bromide], named with G<12-2-12>} to a chloroform casting membrane solution of the PSF by a simple physical blending method; casting to form a membrane on a glass plate by tape casting method, immersing the dried film in a potassium hydroxide solution, and preparing hydroxyl ion type composite die. The aniomic membrane prepared according to the method has ultralow swelling degree, excellent alkaline resistant performance and favorable mechanical property, the conductivity of the membrane is effectively improved, and the problems of poor alkaline resistance, overhigh swelling, poor mechanical property and the like caused by overhigh grafting percent of the polysulfone modified anionic membrane are solved.

The invention discloses a preparation method of a modified poly (vinylidene fluoride-co-hexafluoropropylene) grafted vinyl imidazole anion exchange membrane. The preparation method comprises the following steps: (1) fully stirring poly (vinylidene fluoride-co-hexafluoropropylene) and DMAc in a container to obtain a transparent solution A; (2) slowly adding a strong alkali alcohol solution into the solution A, and stirring to obtain a solution C; (3) slowly adding the solution C into excessive deionized water to obtain a fibrous solid, washing the solid with deionized water until the solid is neutral, and performing vacuum drying to obtain a solid D; (4) dissolving the solid D, vinyl imidazole and benzoyl peroxide in NMP to obtain a solution E; and (5) carrying out heating reaction on the solution E in a nitrogen atmosphere, adding 1, 4-dibromobutane, fully stirring, paving the obtained solution on a clean glass plate, and carrying out vacuum drying to obtain the modified poly (vinylidene fluoride-co-hexafluoropropylene) grafted vinyl imidazole anion exchange membrane. The prepared membrane is excellent in acid concentration performance, good in acid resistance and low in swelling degree.

The invention provides a multi-quaternary ammonium side long-chain type polysulfone anion exchange membrane and a preparation method thereof, which belong to the field of high polymer chemistry and alkaline anion exchange membrane fuel cells. The anion exchange membrane comprises polysulfone with different chloromethylation degrees and long hydrophobic chain type quaternary ammonium salt with a plurality of quaternary ammonium functional groups. A long side chain is grafted to chloromethylated polysulfone through a Menshutkin reaction, and a target membrane material is prepared through membrane forming by a tape casting method. By constructing a hydrophilic/hydrophobic microphase separation structure, an effective ion channel is formed, and the hydroxyl conductivity of the membrane is improved; meanwhile, a hydrophobic chain containing long alkyl intervals can reduce the swelling degree of the quaternary ammonium salt membrane, the membrane has good dimensional stability, and the problems of ionic conductivity and dimensional stability existing for a long time in a membrane material are effectively solved. The hydroxyl conductivity of the multi-quaternary ammonium side long-chain type polysulfone anion exchange membrane can reach 0.113 S cm<-1> at the temperature of 80 DEG C, and the alkaline anion exchange membrane with excellent performance is obtained.

The invention provides a preparing method of a nano-adsorbent for chemical waste liquid treatment. The method specifically includes the steps of firstly, preprocessing styrene-divinylbenzene ion exchange resin; secondly, preparing a crosslinking product of styrene-divinylbenzene ion exchange resin and polydopamine; thirdly, loading nanometer metal oxide. By means of the adsorbent, on one hand, a styrene-divinylbenzene ion exchange resin framework has small nanometer aperture and high specific surface area and provides bountiful adsorption sites; on the other hand, polydopamine is crosslinked on the surface of the framework and in the framework, and the adsorption performance is further improved; finally, the nano-adsorbent quite excellent in performance is obtained by loading nanometer oxide, and the adsorbent has quite excellent performance in dye waste solutions, heavy-metal-containing waste solutions, phosphorus waste solutions, arsenic waste solutions and antimony waste solutions.

The invention relates to the technical field of food active packaging films, in particular to an antibacterial fresh-keeping composite freeze-thawed edible film for chilled fresh meat, a preparation method of the antibacterial fresh-keeping composite freeze-thawed edible film and an application method of the antibacterial fresh-keeping composite freeze-thawed edible film in chilled fresh meat fresh keeping and color protection. The main process parameters are as follows: freezing and thawing is performed for three times, the concentration of calcium lactate is 3%, calcification is performed for 6 minutes, sodium alginate addition amount is 60%, and the tensile strength of the sodium alginate/hyaluronic acid composite film obtained under the condition is 10.41 MPa. The main technical purposes are that excellent renewable natural macromolecular sodium alginate and hyaluronic acid are used as film-forming base materials, the cross-linking agent calcium lactate with a color protection effect is added to produce an active packaging film, the mechanical property of the film is improved through physical treatment of freeze thawing, a green, safe and degradable composite edible film is prepared, the quality deterioration process of the chilled meat in the cold storage process can be effectively delayed, and the edible quality of the chilled meat is kept.

The invention discloses a preparation method of a polyvinylidene fluoride-polyvinyl alcohol composite proton exchange membrane and belongs to the field of a battery electrolyte material. The preparation method comprises the following steps of: firstly preparing a polymer solution by dissolving polyvinyl alcohol in mixed liquid of dimethyl sulfoxide and water; adding silicon tetrachloride and sodium tungstate to the polymer solution; heating, stirring, and then adding polyvinylidene fluoride; carrying out oil bath in vacuum, heating and stirring so as to form a solution; pouring the solution on a polytetrafluoroethylene glass plate and drying to form a membrane, thus obtaining the needed silicotungstic acid and silicon dioxide doped polyvinylidene fluoride-polyvinyl alcohol composite proton exchange membrane. The proton exchange membrane prepared by the method has very good proton electrical conductivity, low methyl alcohol permeability and relatively low swelling degree and is favorable for large-scale production.

The invention discloses a fuel oil resistant ethylene-propylene-diene monomer (EPDM) formula which is characterized by comprising raw materials, namely an ethylene-propylene-diene monomer, paroline, fast extruding furnace black, half-reinforced carbon black, silicon powder, CTP-80, zinc oxide, stearic acid, a composite accelerant GA, sulfur and 2,2,4-trimethyl-1,2-dihydroquinone polymer (RD) 1-3.A raw ethylene-propylene-diene monomer is of a grade of a high molecular weight, a high ethylene content and a high ENB content, and although the intrinsic quality that the EPDM (Ethylene-Propylene-Diene Monomer) is poor in oil resistance is not changed, the fuel oil resistance swelling degree of the rubber is reduced to a certain extent; the novel composite accelerant GA comprises only one accelerant instead of multiple raw materials, and is a special EPDM accelerant and is compounded with a small amount of sulfur, so that the vulcanization effect is good, and a product is free of blooming; the formula is applicable to vulcanization of a glue injection process; and the system is relatively rapid in rubber compound vulcanization speed, and vulcanized rubber is excellent in physical property and good in thermal oxidation resistance, ozone aging resistance and oil resistance.