345 results about "Divinylbenzene" patented technology

The invention provides transparent high-impact-resistance heat-resistant MBS (methyl methacrylate-butadiene-styrene) resin and a preparation method thereof, and relates to the field of high polymer material preparation methods, the transparent high-impact-resistance heat-resistant MBS resin is prepared from the following raw materials: water, ethanol, maleic anhydride, an emulsifier, MBS resin grafted latex, potassium persulfate and an antioxidant; the MBS resin grafted latex is prepared from the following raw materials: water, modified styrene-butadiene latex, sodium hydrogen sulfite, potassium persulfate, methyl methacrylate and styrene, the modified styrene-butadiene latex is prepared from the following raw materials: a pre-emulsion, glycidyl methacrylate, ammonium persulfate, divinyl benzene and potassium persulfate; the pre-emulsion is prepared from the following raw materials: water, an emulsifier, butadiene and styrene. The product is good in heat resistance and good in PVC modification effect, and the modified PVC composite material is high in light transmittance, high in cantilever beam impact strength and resistant to aging.

The invention discloses a magnetic ion exchange resin and a preparation method thereof, and the preparation method comprises the following steps: preparing a reaction solution which comprises magnetic particles, glycidyl methacrylate, divinylbenzene and a photoinitiator; the mass ratio of the glycidyl methacrylate to the divinyl benzene is (4.5-10): 1; an ultraviolet-initiated polymerization step: irradiating the reaction solution by ultraviolet light to initiate a polymerization reaction to obtain magnetic microspheres; a functional modification step: mixing the magnetic microspheres with an ammoniation reagent for ammoniation reaction to prepare ammoniated magnetic microspheres; and mixing the ammoniated magnetic microspheres with an alkylation reagent, and carrying out an alkylation reaction to prepare the magnetic ion exchange resin. According to the method, the production time is remarkably shortened, the extra energy consumption is reduced, and the process production flow is effectively simplified.

The present invention relates to a monolithic bipolar membrane with a low transmembrane voltage and a preparation method thereof. The preparation method includes the following steps: preparing a membrane liquid with styrene and divinylbenzene; heating the membrane liquid, and then impregnating a polyolefin thin membrane; polymerizing an impregnated thin membrane and preparing a basement membrane; producing the basement membrane into a semi-anion membrane; additionally partially sulfonating and additionally quaternizing one side of the semi-anion membrane; then, soaking the bipolar membrane in a FeCl2 solution, transforming the bipolar membrane in an alkaline solution, and preparing the bipolar membrane. The present invention effectively reduces the transmembrane voltage, thereby being beneficial to reducing energy consumption.

The invention discloses a high-efficiency composite catalyst for waste gas purification and a use method thereof, belongs to the technical field of catalysts, and aims to solve the technical problems that a zeolite molecular sieve used as a VOCs catalyst in the prior art is high in hydrophilicity, easy to cause a catalyst poisoning phenomenon and low in adsorption efficiency. The method comprises the following steps; the preparation method comprises the following steps: mixing styrene, divinyl benzene, a hydrophobic metal catalyst and a polar monomer, adding a related auxiliary agent to obtain an oil phase, mixing the oil phase and a water phase, and carrying out post-process treatment to obtain the high-efficiency composite catalyst for waste gas purification. A zeolite molecular sieve is used as a carrier, a hydrophobic inorganic adsorption material is prepared through modification of a modified fluorine-containing silane coupling agent, then the hydrophobic inorganic adsorption material is soaked in a mixed transition metal oxide solution, and the hydrophobic metal catalyst is obtained and has the advantage of being high in catalytic efficiency.

The invention discloses a hydrophobic porous adsorption material for removing perfluorooctanoic acid in water and application of the hydrophobic porous adsorption material. The hydrophobic porous adsorption material is prepared by carrying out free radical polymerization reaction on an imidazolyl ionic liquid monomer and divinyl benzene. The hydrophobic porous adsorbent combines the advantages of good pore channel diffusion, electrostatic adsorption, hydrophobic interaction and the like, and shows excellent adsorption performance and extremely high adsorption rate under different initial concentrations of perfluorooctanoic acid. The adsorption material provided by the invention is simple in preparation method and low in cost, the adsorption performance of the adsorption material on the perfluorooctanoic acid is remarkably improved through the synergistic effect of multiple mechanisms, and the adsorption material is an effective scheme for efficiently removing the perfluorooctanoic acid.

The invention relates to the field of ion exchange resin, and discloses quaternary ammonium type anion exchange resin, a preparation method and application thereof, and a catalytic hydration reaction method of an epoxy-containing compound. The anion exchange resin comprises a resin matrix # imgabs 0 # and a quaternary ammonium group connected with the resin matrix # imgabs 1 # through an alkylene group; wherein the resin matrix # imgabs2 is a hydrogenated styrene-dienylbenzene copolymer, and the styrene-dienylbenzene copolymer contains a styrene structural unit as shown in a formula (1), a dienylbenzene structural unit as shown in a formula (2), a # imgabs3 # formula (1) and a # imgabs4 # formula (2); in the formula (1), R11 is alkyl or hydrogen, and R12 is alkyl or hydrogen; in the formula (2), n is an integer between 0 and 2. The quaternary ammonium type anion exchange resin provided by the invention has excellent swelling resistance.

The invention discloses a method for catalyzing melamino-formaldehyde resin methylation reaction by solid acid. According to the invention, epoxy silane coupling agent grafted modified nanocellulose is introduced into sulfonated styrene-divinyl benzene cross-linked copolymer microspheres for in-situ crystal cross-linking, so that the problems that the traditional sulfonated polystyrene resin is poor in mechanical strength and solution solubility resistance, low in cycle index, easy to swell and fall off and the like are effectively solved; the prepared solid acid resin has the characteristics of high reaction activity, high proton transfer rate, high mechanical strength, high cyclicity and easiness in solid-liquid separation, and by utilizing the solid acid resin to catalyze the etherification reaction of the melamino-formaldehyde resin, the reaction temperature and the production energy consumption are reduced, the reaction time is shortened, the product quality and the production efficiency are improved, and the production cost is reduced. The problems of environmental protection and energy consumption caused by the generation of a large amount of VOCs in the etherification reaction of the traditional liquid catalyst for synthesizing the high-etherified melamine formaldehyde resin and the by-product inorganic salt in the subsequent process are solved.

The invention discloses an imidazolyl polyionic liquid catalyst and a preparation method and application thereof, belonging to the technical field of five-membered cyclic carbonate synthesis. The invention polymerizes an imidazolyl polyionic liquid and divinylbenzene to obtain an imidazolyl polyionic liquid catalyst, and uses the catalyst to catalyze carbon dioxide and styrene to prepare styrene cyclic carbonate in one step. The imidazolyl polyionic liquid catalyst can efficiently convert styrene into styrene cyclic carbonate (the yield of styrene cyclic carbonate is greater than 70%), and the catalytic performance of the imidazolyl polyionic liquid catalyst is not significantly reduced after centrifugal separation and drying. The imidazolyl polyionic liquid catalyst provided by the invention has the advantages of high catalytic activity, simple separation, good circulation performance, no need for solvents and co-catalysts, etc.

The invention belongs to the technical field of functional resin, and particularly relates to macroporous adsorption resin for sugar decolorization and a preparation method and application thereof.The preparation method of the macroporous adsorption resin for sugar decolorization comprises the following steps that water, a dispersing agent and a polymerization inhibitor are mixed, and a water phase is obtained; mixing a monomer, an initiator and a pore-foaming agent to obtain an oil phase; mixing the water phase and the oil phase, standing, shaping, carrying out polymerization reaction, and removing the pore-foaming agent to obtain matrix white balls; the monomer comprises at least one of divinylbenzene, styrene and methyl acrylate; in the oil phase, the mass ratios of the monomer, the initiator and the pore-foaming agent are respectively 36.38%-41.5%, 0.34%-0.45% and 58.05%-63.19%; and mixing the matrix white balls and Lewis acid, and carrying out a post-crosslinking reaction to obtain the macroporous adsorption resin for sugar decoloration. The synthesis process is low in equipment requirement, simple and convenient to operate, low in cost and environment-friendly; and the prepared product has high decolorization rate and can be regenerated.

The invention relates to the field of gel materials, and discloses biomass gel and a preparation method and application thereof.The method comprises the steps that 1, in an inert atmosphere 1, in the presence of a mixed solvent 1, polyether, 2-acrylamide-2-methylpropanesulfonic acid, dimethylaminoethyl methacrylate, divinylbenzene and an initiator are subjected to a polymerization reaction, and an intermediate is obtained; (2) in an inert atmosphere 2, in the presence of a mixed solvent 2, carrying out a cross-linking reaction on the intermediate, a biomass raw material and a trivalent iron salt to obtain biomass gel; the biomass raw material is selected from at least one of alkali lignin, dealkalized lignin, sodium lignin sulfonate, calcium lignin sulfonate, tannic acid, cellulose and inulin; by adopting the method disclosed by the invention, the biomass gel which is resistant to high temperature and salt and is not easy to dissociate can be prepared.

The invention belongs to the field of pharmaceutic adjuvants, and particularly relates to a method for preparing sodium polystyrenesulfonate resin through a centrifugal interfacial membrane emulsification technology and application of the sodium polystyrenesulfonate resin. The method comprises the following steps: by taking a mixed solvent of styrene, divinylbenzene and benzoyl peroxide as a dispersion phase and a polyvinyl alcohol solution as a continuous phase, carrying out centrifugal interfacial membrane emulsification, then carrying out suspension polymerization reaction to obtain polystyrene-divinylbenzene microspheres with narrow particle size distribution, and finally, carrying out sulfonation reaction and alkali exchange to obtain the polystyrene-divinylbenzene composite microsphere. The final product sodium polystyrenesulfonate resin is obtained. The resin prepared by controlling the centrifugal rotating speed, the centrifugal time and the using amount of the dispersing agent, the cross-linking agent and the sulfonating agent and combining a centrifugal interfacial membrane emulsification technology is in a dry golden brown powder shape, the average particle size is 60-100 microns after the resin is dispersed in water, and particles of the resin are uniformly distributed and are of a spherical structure. Meanwhile, the preparation method is simple in preparation process, short in operation time, low in energy consumption, good in economic benefit, suitable for industrial production and wide in market application prospect.

The invention discloses zwitterionic concrete internal curing hydrogel based on humidity-pH dual responsiveness and a preparation method of the zwitterionic concrete internal curing hydrogel, and belongs to the technical field of building materials. The water-based cleaning agent is prepared from the following raw material components in percentage by weight: 6%-8% of N-vinyl imidazole, 8%-12% of 2-methylimidazole, 6%-8% of 2-acrylamido-2-methylpropanesulfonic acid, 2%-4% of sodium p-styrenesulfonate, 26%-30% of acrylic acid, 18%-21% of N-vinyl pyrrolidone, 15%-18% of glycidyl methacrylate, 2%-5% of nano montmorillonite powder, 0.05%-0.1% of divinyl benzene, 0.05%-0.15% of N, N-dimethylformamide and the balance of water. The invention discloses an anti-freezing agent which is prepared from the following components in percentage by weight: 0.1%-0.3% of N, N-methylene bisacrylamide, 0.1%-0.3% of 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propane-1-ketone, 0.5%-0.8% of ammonium persulfate and 0.5%-0.8% of sodium hydrogen sulfite. Double response to the internal humidity and pH value of the concrete can be achieved, and the requirement for precise internal curing of modern high-performance concrete is met.

The invention discloses a hydrophobic modified manganese-doped copper-based catalyst for preparing methanol through CO2 thermal reduction hydrogenation as well as a preparation method and application of the hydrophobic modified manganese-doped copper-based catalyst, and belongs to the technical field of catalysts. The preparation method of the catalyst comprises the following steps: mixing a metal salt mixed solution of a copper salt, a zinc salt, an aluminum salt and a manganese salt with an alkaline solution of a sodium salt, and controlling the pH value; heating, aging, standing and layering; washing the precipitate, drying and roasting to obtain a manganese-doped copper-based catalyst to be hydrophobically modified; the preparation method comprises the following steps: carrying out a hydrothermal reaction on divinyl benzene and a DMF solution of epoxy resin, washing and drying a white solid obtained by the reaction to obtain a hydrophobic material nano-porous polydivinyl benzene; the preparation method comprises the following steps: mixing a hydrophobic material and a manganese-doped copper-based catalyst to be hydrophobically modified, grinding, tabletting and forming to obtain the hydrophobically modified manganese-doped copper-based catalyst. The CO2 adsorption capacity of the catalyst is improved, the monatomic dispersion degree of the catalyst is promoted, and large-scale low-steric-hindrance hydrophobic modification of an active phase is realized.

The invention relates to preparation of metal-labeled plastic microspheres, and belongs to the technical field of high-molecular polymers. The preparation method comprises the following steps: firstly, preparing a polyacrylonitrile inner core by an emulsion polymerization method, adding rare metal salt into the polyacrylonitrile inner core while synthesizing the polyacrylonitrile inner core, slowly injecting styrene, a cross-linking agent divinyl benzene and a functional monomer into a system to form a carboxyl modified polystyrene outer shell, and carrying out heat treatment on the carboxyl modified polystyrene outer shell to obtain the high-performance polystyrene composite material. And thus, the metal-labeled carboxyl modified nano plastic microspheres are obtained. According to the preparation method disclosed by the invention, the rare metal is coated inside the acrylonitrile, and the crosslinking agent is used for enhancing the crosslinking degree of the styrene, so that the metal marker in the prepared metal-labeled nano-plastic microsphere is stable in combination and hardly leaks from the plastic microsphere, and the metal-labeled nano-plastic microsphere can be used for quantifying trace micro-plastic in the environment; the metal chelated polystyrene nanospheres prepared by the method are large in specific surface area and uniform in particle size.

The invention provides a collection and detection method for electronic cigarette atomized released substances, and belongs to the technical field of electronic cigarette detection. The method comprises the following steps: step 1, adsorbing and collecting aerosol release substances generated after atomization of electronic cigarette atomized liquid by using a solid-phase extraction column, wherein the solid-phase extraction column is filled with an adsorbing material polyethylene divinylbenzene; step 2, eluting the solid-phase extraction column after adsorption in the step 1 to obtain an eluent as a to-be-detected sample solution; and 3, detecting the content of a sweetening agent in the to-be-detected sample solution obtained in the step 2 by using a liquid chromatograph, and detecting the content of a cooling agent and a flavor substance in the to-be-detected sample solution by using a gas chromatograph-mass spectrometer. The method provided by the invention has very good trapping efficiency on substances with various phase states and pH values in aerosol release substances of the electronic cigarette, especially has a relatively strong adsorption effect on low-carbon ester and terpene flavor substances, improves the detection accuracy, and is suitable for simultaneous detection of various components in electronic cigarette products.

The invention belongs to the technical field of new energy materials and lithium ion batteries, and relates to a PVDF-HFP / LLZO composite solid electrolyte membrane, a preparation method and application of the PVDF-HFP / LLZO composite solid electrolyte membrane in a flexible electronic device. The composite solid electrolyte membrane disclosed by the invention comprises a matrix formed by PVDF-HFP (Polyvinylidene Fluoride-Hexafluoropropylene) nanofibers and LLZO (Likelike Likelike Zinc Oxide) particles, and a three-dimensional network structure formed by crosslinking DVB (Divinylbenzene) in the matrix, wherein SDS (Sodium Dodecyl Sulfate) is adsorbed on the surfaces of the LLZO particles. A flexible fiber scaffold structure is constructed through an electrostatic spinning process, and sodium dodecyl sulfate (SDS) is introduced into a precursor to carry out interface regulation and control treatment on the surface of an inorganic filler LLZO, so that the dispersity and wettability of the inorganic filler LLZO in a polymer matrix are improved; meanwhile, divinylbenzene (DVB) is introduced as a cross-linking monomer, and in-situ construction of a three-dimensional network structure is realized under a heat treatment condition, so that the mechanical stability and ionic conductivity of the membrane material are remarkably improved.

The invention discloses a low-carbon olefin alkylation catalyst and a preparation method thereof, and belongs to the technical field of molecular sieve catalysts, the low-carbon olefin alkylation catalyst comprises the following components by mass: 77-79.6% of a g-C3N4 / ZMQ-1 molecular sieve, 20-22% of a polydivinylbenzene-CeSmAgPOx nanoparticle cocatalyst, and the balance of a metal auxiliary agent with a hydrogenation function; the poly (divinyl benzene)-CeSmAgPOx nanoparticle cocatalyst is prepared from poly (divinyl benzene) microgel and a CeSmAgP sol system according to a mass ratio of 1: (1.2 to 1.4); the g-C3N4 / ZMQ-1 molecular sieve is obtained by carrying out high-temperature ball milling modification treatment on a ZMQ-1 molecular sieve and a g-C3N4 nanosheet according to a mass ratio of (3.6-5.7): 1. By adopting the mode, the low-carbon olefin alkylation catalyst disclosed by the invention has the advantages that the stability is strong, the catalyst is not easy to inactivate, the regeneration frequency is favorably reduced, the selectivity of the target product TMP can reach 80% or above, and the economic value of industrial production is favorably improved.

The invention provides a PTA wastewater treatment method, which comprises: carrying out biodegradation treatment and membrane separation treatment on to-be-treated PTA wastewater, carrying out adsorption treatment through an adsorption resin, and carrying out ultrafiltration and reverse osmosis treatment, wherein the adsorption resin is formed by compounding zeolite and a polymer, and is obtained by the following method: uniformly mixing zeolite, styrene, divinylbenzene, an initiator, a pore-foaming agent and 3-methyl-5-vinylpyridine to obtain an oil phase; uniformly mixing water and a dispersing agent to obtain a water phase; and uniformly mixing the oil phase and the water phase, stirring, and carrying out polymerization reaction to obtain the adsorption resin. According to the PTA wastewater treatment method disclosed by the invention, a physical process and a biochemical process are combined, so that pollutants such as bromide ions can be effectively removed, and the wastewater recycling requirement is met.

The invention relates to the technical field of adsorption materials, in particular to modified adsorption resin for a high-impurity n-heptane raw material and a purification method of the modified adsorption resin. The resin is prepared from the following raw materials: polystyrene-divinylbenzene resin microspheres, chloromethyl ether, 1, 3, 5, 7-tetra (4-chloromethylphenyl) adamantane, 2-methylimidazole and the like. During preparation, polystyrene-divinylbenzene resin microspheres are subjected to chloromethylation to introduce active sites, adamantine crosslinking to construct rigid pore channels, and imidazolyl functionalization to introduce specific adsorption sites. During purification, dynamic adsorption is performed after pretreatment of two stages of adsorption columns, mild regeneration is performed by using an ethanol-acetone mixed solution, isoparaffin, aromatic hydrocarbon and oxygen-containing compounds can be synchronously removed, high-purity n-heptane is obtained, the resin regeneration performance is excellent, and the whole process is easy to industrialize.

The application relates to the field of shoe-making moulds and high polymer foaming forming technology, and discloses a running type basketball shoe tree and a production process thereof. The shoe tree is made of raw materials containing the following components by weight: high-density polyethylene, ethylene-1-octene copolymer, precipitated barium sulfate, dicumyl peroxide, divinylbenzene and powder pre-dispersed foaming agent. The production process of the shoe tree comprises the following steps: constant temperature closed mixing, melt extrusion and air cooling and granulation of all the materials to obtain base rubber particles, injection of the rubber particles into a mould after heating to complete chemical crosslinking and microporous foaming, superposition of a sinusoidal servo pressure maintaining flow field on the material to implement mechanical kneading of the material to promote molecular chain segment relaxation and rearrangement when the temperature is lowered to the semi-cured window period, and finally forced cooling and shaping in a tree to obtain the shoe tree. Through polymer blending and heterogeneous nucleation, and in combination with the sinusoidal servo flow field mechanical kneading to eliminate residual stress, the size precision and mechanical support consistency of the shoe tree are improved.

The invention belongs to the technical field of catalyst preparation, and particularly relates to an ozone catalyst for water treatment and a preparation method thereof, and the preparation method comprises the following steps: uniformly mixing iron-manganese modified zeolite subjected to hot water treatment, TEOS hydrolysate, VTMS hydrolysate, a VSNa solution, divinyl benzene, an initiator, sodium chloride and CMC to obtain slurry, treating the slurry into wet particles, and drying the wet particles to obtain the ozone catalyst for water treatment. Carrying out heating curing treatment on the wet particles to obtain a catalyst precursor, washing the catalyst precursor with deionized water, and then carrying out heat treatment and cooling to obtain the catalyst. The method can effectively reduce the effluent COD of the petrochemical wastewater containing sodium oxalate, and is high in long-term use stability.

The invention belongs to the technical field of aerosol detection, and particularly relates to an aerosol adsorption material, a preparation method, an aerosol collection device and a detection system. The aerosol adsorption material comprises a polymer microsphere skeleton with a porous structure and a metal organic framework nano-material growing on the surface of the polymer microsphere skeleton, and the metal organic framework nano-material radiates outwards and grows along the surface of the polymer microsphere skeleton; wherein the polymer microsphere skeleton comprises a polystyrene-divinyl benzene microsphere, and the metal organic framework nano material comprises Zn-BDC (zinc-boron dichloride). A Zn-BDC metal organic framework nano material is grown on a porous polystyrene-divinyl benzene microsphere skeleton in a radiation manner, so that the composite adsorbent with a multilevel structure is constructed. According to the design, the macrostructure advantage of a polymer skeleton and the nano-scale ultrahigh adsorption performance of an MOF material are combined, synergistic interaction can be achieved, and efficient and accurate capture of all aerosol components (especially nicotine, characteristic aroma small molecules and the like) is achieved.

A macroporous cation exchange resin and its preparation and application method are disclosed. The method involves dispersing polystyrene-divinylbenzene microspheres in dichloroethane to obtain a microsphere suspension. A sulfonating agent, a mixture of fuming sulfuric acid and chlorosulfonic acid, is then slowly added dropwise under cooling and stirring conditions. After the addition is complete, heating is initiated to trigger a polysulfonation reaction. Once the reaction is complete, the reaction mixture is slowly poured into ice water and continuously stirred and diluted until the solution pH reaches 2.5. The solution is then filtered, washed, and dried to obtain a solid resin. This invention simultaneously introduces a matched number of sulfonic acid groups and sulfone groups onto the polystyrene-divinylbenzene backbone. Utilizing the electron-withdrawing effect of the sulfone groups and the rigid framework they form, the stability of the C-H and C-S bonds in the resin is enhanced. This solves the problems of resin structure damage, rapid decline in separation performance, and significantly shortened service life associated with existing cation exchange resins used in treating chromium plating aging solutions.

The invention relates to an adsorbing material for blood perfusion and a preparation method thereof. The preparation method comprises the following steps: providing a hydrophobic porous carrier which comprises styrene-divinyl benzene copolymer microspheres, and introducing a coordination group on the surface of the hydrophobic porous carrier through chemical modification. The average pore size of the hydrophobic porous carrier is 2-50 nm, and the specific surface area of the hydrophobic porous carrier is greater than or equal to 500 m < 2 > / g; the coordination group is selected from at least one of iminodiacetic acid (IDA), ethylenediaminetetraacetic acid (EDTA) and N, N, N-tricarboxymethyl ethylenediamine (TED). The prepared adsorption material is high in A beta removal capacity, has certain removal capacity on heavy metal ions, is good in blood compatibility and excellent in anticoagulation performance, and is an ideal material for preparing a blood perfusion device.

The invention relates to the technical field of resin preparation, in particular to macroporous weak-base anion exchange resin as well as a preparation method and application thereof. The crosslinked styrene-divinylbenzene microsphere matrix obtained by a preparation process of regulating and controlling the crosslinked styrene, the divinylbenzene and the pore-foaming agent and adding the crosslinking agent has the advantages of high mechanical strength, controllable specific surface area, adjustable pore diameter and the like. A macroporous weak base anion exchange resin; according to the method, the total exchange capacity reaches 4.8 mmol / g or above, the resin sphericity in the fatigue strength of 100 cycles is 90% or above, the resin sphericity in the fatigue strength of 300 cycles is 70% or above, the treatment volume ratio (BV) in the first cycle in the xylose decolorization process is 80 or above, and the purposes of improving the resin quality, reducing the environmental pollution and improving the energy efficiency ratio can be achieved.

This invention relates to the field of filter material production technology, specifically to a novel filter material and its preparation process, comprising the following steps: drying and swelling styrene-divinylbenzene copolymer spheres, then adding them to a sulfonation tank; adding concentrated sulfuric acid to the sulfonation tank, starting a first motor to drive a stirring blade for stirring, and heating to carry out the sulfonation reaction; initially, the stirring blade rotates counterclockwise; at the end of the reaction, a second motor is started to drive a lead screw to rotate, causing the moving parts and stirring blades to move to the bottom of the rotating shaft, while simultaneously the gear rotates under the action of the gear plate, causing the stirring blades to rotate 180°, and then rotate clockwise; after sulfonation, a strongly acidic cation exchange resin is obtained. This invention, by setting a driving structure to change the position of the stirring blades according to different reaction stages, and simultaneously changing the tilt angle of the stirring blades, avoids the styrene-divinylbenzene copolymer spheres floating on the surface of concentrated sulfuric acid or accumulating at the bottom of the sulfonation tank, thus preventing a decrease in yield.

The invention discloses melamine glazing powder and a preparation method thereof, and belongs to the technical field of melamine glazing resin. The method is used for solving the technical problems that in the prior art, a melamine glazing powder synthesis process is poor in surface brightness and smoothness and is not resistant to high temperature. The preparation method of the melamine glazing powder comprises the following steps: uniformly mixing and ball-milling a primary material, a lubricant, a curing agent, hybrid resin and poly-2, 2 '-(m-phenyl)-5, 5'-bis-benzimidazole to prepare the melamine glazing powder. Wherein methyl acrylate and divinylbenzene are subjected to suspension copolymerization to synthesize a suspension copolymer; 4-chloromethylstyrene is cross-linked with the suspension copolymer, and composite resin is prepared; and hydrolyzing tetraethyl orthosilicate in the composite resin to prepare the hybrid resin. When melamine and formaldehyde are subjected to polycondensation, p-toluenesulfonamide is adopted for modification, so that the smoothness and the brightness value of the prepared melamine glazing powder are improved. The melamine glazing powder prepared by the invention has the advantages of high surface brightness and smoothness and high temperature resistance.

The application belongs to the field of ion exchange membranes, and discloses a crosslinked fluorine-containing ion exchange membrane and a preparation method and application thereof. Styrene sulfonic acid and 4-vinylbenzyl pentafluorophenol ether are pre-polymerized in an inert gas atmosphere, and divinylbenzene is added in the inert gas atmosphere, and the mixture is poured into a smooth horizontal tank for in-situ crosslinking polymerization reaction. Solvents in the system are evaporated and removed to obtain a pre-prepared ion exchange membrane. After sufficient sulfonation, the ion exchange membrane is washed with 0.5-1 mol / L dilute sulfuric acid and deionized water in sequence until the washing liquid is neutral, and is naturally dried at room temperature. The raw materials are widely sourced and inexpensive, the cost is effectively controlled, the preparation process is relatively simple, the conditions are mild, and the application is suitable for large-scale industrial production. The application has good mechanical properties, high vanadium battery efficiency, excellent durability or corrosion resistance, and can replace the existing ion exchange membrane to be applied to the field of flow battery energy storage.

The application provides a method for improving the mechanical properties of ceramic matrix composites, and relates to the technical field of ceramic matrix composite preparation. The method uses polymethylsilane (PMS) as a ceramic precursor, silicon carbide powder as a filler, divinylbenzene (DVB) as a cross-linking agent, introduces boron nitride as a sintering aid and a second-phase toughening component, and is prepared through six core processes of constant-temperature mixing under nitrogen protection, carbon fiber cloth vacuum impregnation, laminating exhaust forming, tungsten bead weight matching shaping, two-stage gradient sintering and multiple precursor impregnation and densification to obtain high-performance continuous carbon fiber reinforced silicon carbide composite materials. The sintering promotion effect and dispersion toughening mechanism of boron nitride are used, and the optimized forming process of layer-by-layer exhaust and weight matching shaping is used to effectively reduce the porosity of the matrix, and significantly improve the material density, bending strength and fracture toughness. The process parameters of the application are quantifiable and controllable, the batch stability is high, no special equipment is needed, and the application can be adapted to large-scale production.

The invention discloses a method for determining acetate and malate of a compound electrolyte injection (II) by liquid chromatography. According to the method, acetate and malate are detected by adopting high performance liquid chromatography, sulfonic acid type polystyrene and divinylbenzene copolymer cation exchange resin H type is used as a filler, the detection wavelength is 200-210 nm, the flow rate is 0.5-1.0 ml / min, the retention time of acetate is 16 min, the retention time of malate is 12 min, the column temperature is 50-90 DEG C, the sample size is 5-50 microliters, and a mobile phase is a 0.005 mol / L sulfuric acid solution. And calculating the content of acetate and malate by adopting an external standard method. The method is high in specificity, good in precision and high in accuracy, the solution is stable within 48 hours, and the method can be used for quality control in preparation production.