297 results about "Hypophosphorous acid" patented technology

The invention discloses a method for deeply removing readily oxidizable substances in high-purity electronic-grade phosphoric acid, which deeply removes the readily oxidizable substances in the high-purity electronic-grade phosphoric acid in a mode of combining ozone oxidation and resin adsorption to obtain a high-purity electronic-grade phosphoric acid finished product with extremely low readily oxidizable substance concentration. The specific process mainly comprises the following three steps: S1, introducing ozone gas at a certain temperature to oxidize readily oxidizable substances such as phosphorous acid and hypophosphorous acid in phosphoric acid into phosphoric acid so as to reduce the concentration of the readily oxidizable substances; s2, feeding the phosphoric acid subjected to ozone oxidation into an adsorption reactor to be in contact with an adsorbent, and further removing residual readily oxidizable substances in the phosphoric acid; and S3, filtering the phosphoric acid subjected to adsorption treatment through a filter element for separation, and removing residual small particles and impurities to obtain the electronic-grade phosphoric acid with readily oxidizable substances removed. The method is simple in process, controllable in condition, convenient to operate, safe and environment-friendly, does not need to add an additional solvent, avoids introduction of new impurities, reduces secondary pollution, and is suitable for preparing high-purity electronic-grade phosphoric acid.

The invention discloses a flame retardant with a double-layer microcapsule structure, a flame-retardant polyurethane material as well as a preparation method and application of the flame-retardant polyurethane material, and belongs to the technical field of flame retardants. The material is a multifunctional flame retardant with a double-layer core-shell structure, a shell layer is calixarene boric acid resin, a middle shell layer is melamine phthalic anhydride resin, and a core layer is hydroxyapatite modified aluminum hypophosphite. Due to the high cross-linking degree between polymers, the flame retardance of polyurethane is improved, meanwhile, the mechanical property of the polyurethane is improved, and the flame retardance and seawater corrosion resistance of the material are synergistically enhanced through hydroxyapatite dispersed in the core layer. The double-shell layer has excellent hydrophobicity, prevents internal aluminum hypophosphite from being affected with damp and has anti-fouling and self-cleaning effects, and the prepared flame-retardant polyurethane composite material has excellent tensile and flexible characteristics due to a double network of hydrogen bonds and covalent bonds.

The invention relates to a base membrane for a composite current collector based on SiO2 nano composite modification and a preparation method of the base membrane. Synergistic modified nano SiO2 is compounded with aluminum hypophosphite, montmorillonite and the like to form modified auxiliary particles, the modified auxiliary particles and PET master batches are subjected to blending extrusion, and meanwhile, the surface of the base membrane is coated with a modified coating containing nano SiO2, so that the composite current collector is obtained. The mechanical property, the thermal stability and the flame retardance of the base film are obviously improved.

The invention discloses a high-elasticity regenerated polyester material for chemical fibers and a preparation method thereof, and relates to the technical field of high polymer material regeneration. The invention discloses a high-elasticity regenerated polyester material for chemical fibers. The composite material is prepared from the following raw materials in parts by weight: 8 to 12 parts of glass fiber, 0.2 to 0.4 part of silane coupling agent KH-550, 4 to 6 parts of absolute ethyl alcohol, 4 to 6 parts of aluminum hypophosphite, 2 to 4 parts of melamine cyanurate, 0.05 to 0.15 part of aryl sodium phosphate, 65 to 75 parts of modified regenerated polyester, 20 to 30 parts of modified bio-based elastomer, 5 to 10 parts of maleic anhydride grafted polyolefin elastomer, 0.3 to 0.8 part of antioxidant and 1 to 2 parts of carbon black master batch. 0.1 to 0.3 part of a silicone lubricant; and 5 to 10 parts of didodecyl dimethyl ammonium chloride. Through supercritical chain extension, nano grafting and gradient crystallization technologies, the mechanical property and elasticity of the regenerated polyester are improved. The modified bio-based elastomer, the flame retardant and the antistatic agent have a synergistic effect, so that the material has high elasticity, flame retardance and antistatic functions. The method is suitable for high-end application in the field of chemical fibers, realizes high-value recycling of waste polyester, and has remarkable environmental protection benefits.

The invention relates to the technical field of waste liquid treatment, in particular to a method for efficiently separating nickel, hypophosphorous acid and ammonia from chemical nickel plating waste liquid, which comprises the following steps: S1, nanofiltration: carrying out nanofiltration separation on chemical nickel plating waste water by using a roll type nanofiltration membrane to obtain nickel-containing waste water and waste water containing hypophosphorous acid and ammonia; s2, bipolar membrane electrodialysis: setting an arrangement mode of a bipolar membrane electrodialysis system as follows: sequentially arranging an anode, a first bipolar membrane, an anionic membrane, a cationic membrane, a second bipolar membrane and a cathode, introducing wastewater containing hypophosphorous acid and ammonia into a desalination chamber, and adding deionized water into an acid chamber and an alkali chamber to obtain a hypophosphorous acid solution and ammonia gas; separation of hypophosphorous acid and ammonia is realized; according to the method, hypophosphite and ammonium in the chemical nickel-plating waste liquid are efficiently separated, and the method has important significance on improving the resource utilization efficiency of phosphorus and ammonia in the chemical nickel-plating waste liquid and reducing the treatment difficulty and treatment cost of the chemical nickel-plating waste liquid.

The invention belongs to the technical field of batteries, and particularly relates to a microcapsule type flame retardant and a preparation method thereof, a composite phase change material and a preparation method and application thereof. According to the microcapsule type flame retardant provided by the invention, the melamine cyanurate is used for wrapping, aluminum hypophosphite can be isolated from a heat source, and decomposition of the aluminum hypophosphite is delayed, so that the problem of poor stability of the aluminum hypophosphite is effectively solved; the melamine cyanurate and the phosphorus-based flame retardant can also achieve a phosphorus-nitrogen synergistic flame retardant effect, so that the flame retardance of the flame retardant is improved. Furthermore, the invention also provides the composite phase change material, and the preparation raw materials comprise a phase change matrix, a supporting framework, a heat conduction reinforcing agent and a flame retardant, the flame retardant is ammonium polyphosphate and a microcapsule type flame retardant; when the composite phase change material is applied to a battery thermal management system, heat generated by a battery can be absorbed in time, the temperature of the battery is kept within a reasonable range, and when the battery is on fire abnormally, the composite phase change material can play a role in flame retardance and reduce the risk of thermal runaway.

The invention belongs to the technical field of high-molecular flame retardants, and relates to a method for preparing spherical aluminum hypophosphite with a rough surface at low temperature and normal pressure, which comprises the following steps: adding aluminum sulfate hexahydrate into deionized water for dissolving according to a certain molar ratio, adding sodium hypophosphite monohydrate into deionized water and ethylene glycol for dissolving, and stirring under the condition of mechanical stirring to obtain spherical aluminum hypophosphite; the preparation method comprises the following steps: dropwise adding an aluminum sulfate hexahydrate aqueous solution into a sodium hypophosphite monohydrate solution at a relatively low temperature to obtain a mixed solution, heating in a water bath to 90 DEG C, reacting with the mixed solution to generate aluminum hypophosphite, washing the prepared aluminum hypophosphite slurry with deionized water and absolute ethyl alcohol in sequence, centrifuging, drying in vacuum, and grinding to obtain the spherical aluminum hypophosphite. Under general double decomposition reaction conditions, the spherical aluminum hypophosphite is synthesized at low temperature and normal pressure by controlling the dropwise adding temperature of the raw materials and adopting water and ethylene glycol as a mixed solvent. The prepared aluminum hypophosphite is excellent in morphology, narrow in particle size distribution and good in dispersity.

The invention discloses a low-temperature-resistant working electrolyte for a liquid capacitor and a preparation method of the low-temperature-resistant working electrolyte, and relates to the technical field of electrolytes for capacitors. The low-temperature-resistant working electrolyte is prepared from the following raw materials: ethylene glycol, an auxiliary solvent, a solute, ammonium hypophosphite, a synergist, a stabilizer, 1-ethyl-3-methylimidazolium bis (trifluoromethylsulfonyl) imine, boron nitride nanosheets and 2, 2, 2-trifluoroethyl acrylate. According to the invention, while the auxiliary solvent with a specific proportion is added, the synergist capable of improving the conductivity, the cycle life, the low-temperature ion mobility and the low-temperature power density and the 2, 2, 2-trifluoroethyl acrylate capable of further improving the electrochemical performance stability at the low temperature are also introduced, so that the low-temperature electrochemical performance of the lithium ion battery is improved. And a specific preparation method capable of preventing agglomeration and improving the smoothness of an ion conduction path is combined. Therefore, the electrolyte is more excellent in chemical performance at low temperature and wider in application prospect.

The invention belongs to the technical field of flame-retardant materials, and particularly relates to a prismatic aluminum hypophosphite compound as well as a preparation method and application thereof. The prismatic aluminum hypophosphite compound is prepared from aluminum hypophosphite, layered montmorillonite and nano silicon dioxide, and the weight percentage of the layered montmorillonite is 0.043 to 0.087 weight percent and the weight percentage of the nano silicon dioxide is 0.0036 to 0.0181 weight percent based on 100 weight percent of the aluminum hypophosphite; the particle size D10 of the prismatic aluminum hypophosphite compound is 1-3 microns, the particle size D50 of the prismatic aluminum hypophosphite compound is 5-8 microns, the particle size D90 of the prismatic aluminum hypophosphite compound is 10-15 microns, the particle size D97 of the prismatic aluminum hypophosphite compound is smaller than 20 microns, and the prismatic aluminum hypophosphite compound is of a single prismatic crystal structure or a regular structure in which a plurality of prismatic crystals are mutually embedded. The prismatic aluminum hypophosphite compound provided by the invention has a specific morphology and is especially suitable for a polyurethane flame-retardant system.

The invention belongs to the technical field of X-ray detection, and particularly relates to lead-free two-dimensional double perovskite, a preparation method of the lead-free two-dimensional double perovskite and an X-ray detector manufactured based on the perovskite. The lead-free two-dimensional double perovskite is applied to X-ray detection. According to the preparation method, histamine dihydrochloride (C5H11Cl2N3Cl), silver chloride (AgCl) and bismuth trioxide (Bi2O3) are mainly used as raw materials, a mixed solution of hydrobromic acid (HBr) and hypophosphorous acid (H2PO2) is used as a solvent, a single crystal material ((C5H9N3) 2AgBiBr8 single crystal) is prepared through a hydrothermal method, and the two sides of the single crystal are coated with silver paste to serve as electrodes, so that the direct type X-ray detector is obtained. The preparation method disclosed by the invention has the characteristics of simplicity, easiness in operation, low requirement on equipment, low cost, low energy consumption and suitability for expanded production.

The invention provides a polymer additive as well as a preparation method and application thereof, and the preparation method comprises the following steps: carrying out free radical reaction on a hypophosphorous acid aqueous solution and an antioxidant with ethylene under the action of an initiator to obtain a diethyl hypophosphorous acid aqueous solution; the diethyl phosphinic acid aqueous solution, sulfuric acid and metal hydroxide are subjected to a reaction, then alkali liquor is added, and diethyl phosphinate slurry with the pH value being 3.8-4.2 is obtained; mixing and stirring the diethyl hypophosphite slurry and a flocculating agent to obtain diethyl hypophosphite flocculate, and then filtering, washing and drying to obtain the polymer additive. Through the design of the preparation method, the polymer additive with a low acid value can be obtained, and when the polymer additive is used as a flame retardant to prepare a polymer material, the precipitation of an auxiliary agent in a high-temperature processing process can be inhibited, and mold scale can be reduced, so that the prepared polymer composition has relatively low content of water boiling precipitates, and the service life of the polymer composition under damp and hot conditions is prolonged.

The invention discloses a halogen-free compound flame retardant and application thereof in an antistatic nylon 66 composite material, and belongs to the technical field of polymer composite materials. The halogen-free compound flame retardant is prepared by compounding 68 parts of an organic aluminum hypophosphite flame retardant, 20 parts of a nitrogen-phosphorus intumescent flame retardant, 10 parts of a two-dimensional layered inorganic substance and 2 parts of a coupling agent through a high-speed mixing and drying process. The halogen-free compound flame retardant is blended with nylon 66, reinforced fibers, an antioxidant and the like, and the composite material is prepared through melt extrusion. According to the compound system, the total dosage of the flame retardant is remarkably reduced, the V-0 flame retardant grade is still achieved under the condition that the thickness is 0.8 mm, and the limit oxygen index exceeds 32%. The composite material has excellent flame retardancy and antistatic property while maintaining good mechanical properties, is suitable for a high glass fiber content system, effectively solves the problems of high flame retardant addition amount, difficult processing, high cost and the like in the prior art, and has the advantages of simple process and excellent comprehensive performance.

The invention provides a high-chirality one-dimensional perovskite single crystal and a preparation method thereof, and the preparation method comprises the following steps: 1, using lead oxide, hydriodic acid, hypophosphorous acid and (R)-1-(1-naphthyl) ethylamine to prepare a white precipitate in a glass bottle; 2, heating the glass bottle, and continuously stirring the liquid containing the white precipitate by using magnetons; and 3, cooling the glass bottle to obtain the single crystal. According to the preparation method of the high-chirality one-dimensional perovskite single crystal, provided by the invention, a material (R)-1-(1-naphthyl) ethylamine with ultrahigh chirality is selected as positive ions of perovskite, so that the grown perovskite single crystal also has ultrahigh chirality; the pure one-dimensional chiral perovskite single crystal which is yellow is obtained by adjusting the ratio of lead oxide to (R)-1-(1-naphthyl) ethylamine; and the obtained single crystal has a flat surface, the size can be as long as 6mm, and the application field of the single crystal is widened.

The invention discloses a catalytic carbonized flame-retardant polyolefin nano composite material as well as a preparation process and application thereof, and relates to the technical field of macromolecular flame-retardant materials. The composite material comprises the following components: a polyolefin matrix, a metal organic framework, aluminum hypophosphite, transition metal nickel, and mercaptan and alkene monomers used for a dynamic mercaptan-alkene click reaction. According to the present invention, the three-time combination flame retardation effect of physical barrier-chemical quenching-pyrolysis gas dilution is achieved, when the fire occurs, the staged catalysis mechanism can accurately respond to different temperature stages, and the nickel ions trigger the polyolefin pre-crosslinking at the temperature of 200-250 DEG C to form the three-dimensional network so as to construct the physical barrier so as to achieve the fire retardation effect; aluminum hypophosphite at the temperature of 300 DEG C or above is pyrolyzed to release acid gas to etch the shell of the MOFs and release the free radical trapping agent, chemical quenching and pyrolysis gas dilution are carried out, and the good mechanical property of the polyolefin material is kept.

The invention relates to the technical field of tire rubber manufacturing, and discloses a tread rubber composition containing modified lignin and a mixing method thereof, and the rubber composition is added with the modified lignin. The modified lignin is water-soluble lignin obtained by modifying lignin by grafting citric acid groups. Citric acid is adopted to modify lignin, a citric acid group is grafted on a lignin group under the catalytic action of sodium hypophosphite to enhance the hydrophilicity of the lignin group, wet mixing is combined, the dispersity of the lignin in rubber is effectively improved, the rolling resistance of the rubber composition is reduced, meanwhile, the added lignin can enhance the strength of a rubber network, and the rolling resistance of the rubber composition is reduced. The tensile property of the rubber is improved.

The invention belongs to the technical field of chemical modification of natural polymer materials, and particularly relates to a modified cellulose adhesive and a preparation method thereof. The modified cellulose adhesive is prepared from the following components in parts by weight: 50 to 70 parts of modified cellulose-based emulsion, 10 to 20 parts of VAE (Vinyl Acetate Ethylene) composite emulsion, 5 to 8 parts of rosin water emulsion, 3 to 8 parts of cross-linking agent and 2 to 5 parts of plasticizer, the modified cellulose is obtained by grafting an epoxy hypophosphite compound and a fluorine-containing pentaphenyl alkynyl dicarboxylic acid compound with a nano cellulose solution; according to the prepared modified cellulose adhesive, targeted improvement of waterproofness, durability and bonding strength is achieved through molecular design.

This case involves a base film for a composite current collector based on SiO2 nanocomposite modification and its preparation method. The present invention forms modified auxiliary particles by synergistically modifying nano-SiO2 with aluminum hypophosphite, montmorillonite, etc., and extrudes them together with PET masterbatch. At the same time, a modified coating containing nano-SiO2 is coated on the surface of the base film, which significantly improves the mechanical properties, thermal stability and flame retardancy of the base film.

The invention provides a treatment process of a byproduct sodium hypophosphite in a phosphorane preparation process, and aims to efficiently remove impurities and prepare a high-purity hypophosphorous acid product. The process comprises the following steps: carrying out small-volume sampling on reaction mother liquor, introducing carbon dioxide gas, and drawing an acidification curve of pH and conductivity; according to the plateau phase of an acidification curve, the CO2 flow rate and the pH value are controlled, step-by-step selective precipitation of impurities such as PO4 < 3->, HPO4 < 2->, Fe < 3 + >, AsO4 < 3-> and S < 2-> is achieved, and loss of a target component H2PO4 < 2-> is avoided; calcium hydroxide turbid liquid is introduced at a proper time to supplement Ca < 2 + > and promote efficient removal of phosphorus, arsenic and sulfur impurities; and subsequently removing excessive Na < + > and Ca < 2 + > through cation exchange, and concentrating to obtain a hypophosphorous acid product with the purity of more than or equal to 99.5%. The method is accurate in process control, thorough in impurity removal and good in repeatability and industrial adaptability, and the resource utilization efficiency of by-products and the added value of products are remarkably improved.

The invention belongs to the technical field of synthetic ester, and particularly relates to a preparation method of fatty acid pentaerythritol ester base oil, which comprises the following steps: carrying out esterification reaction on pentaerythritol and fatty acid in the presence of a catalyst and a color retention agent, and carrying out post-treatment to obtain the fatty acid pentaerythritol ester base oil, the catalyst comprises at least one of stannous octoate, stannous oxalate, stannous oxide, tetrabutyl titanate, isopropyl titanate and sodium hydrogen sulfate; the color retention agent comprises at least one of sodium hypophosphite, hypophosphorous acid, activated carbon and sodium sulfite. The color retention agent sodium hypophosphite is matched with the specific catalyst such as stannous oxalate, so that the petroleum color number of the produced fatty acid pentaerythritol ester base oil is smaller, and meanwhile, the esterification reaction time is shorter.

The invention relates to the technical field of silicone rubber, in particular to high-temperature-resistant flame-retardant silicone rubber, a preparation method thereof and a cable, the high-temperature-resistant flame-retardant silicone rubber comprises a gradient layer material composed of a surface layer material, a transition layer material and a core layer material, and the surface layer material comprises methyl vinyl silicone rubber, superfine furnace black, calcium stannate, polyacrylonitrile aerogel and a flame-retardant premix; the transition layer material comprises methyl vinyl silicone rubber, superfine furnace carbon black, spandex fibers, polyarylester, calcium stannate and a flame-retardant premix; the core layer material is prepared from methyl vinyl silicone rubber, superfine furnace black, aramid fiber, polyarylester, phthalonitrile resin and 2-mercaptobenzothiazole zinc salt; wherein the flame-retardant premix is prepared from hydroquinone bis (diphenyl) phosphate, phenyl ethyl aluminum phosphinate and zinc hypophosphite according to the weight ratio of (6 to 10): (2 to 4): (1 to 3); the problems that an existing material is prone to aging in an extreme environment, the flame retardant effect is poor, and the mechanical property is degraded are effectively solved.

The invention discloses a phosphorus-silicon type Schiff base derivative flame retardant and a preparation method and application thereof.The preparation method comprises the steps that salicylaldehyde and 1, 3-bis (3-aminopropyl)-1, 1, 3, 3-tetramethyldisiloxane react to obtain silicon-containing Schiff base, then P-H on hypophosphorous acid substances and-C = N-on the silicon-containing Schiff base are subjected to an addition reaction, and the phosphorus-silicon type Schiff base derivative flame retardant is obtained. The phosphorus-silicon type Schiff base derivative flame retardant is prepared. The flame retardant contains a plurality of groups such as-OH,-NH-and the like, can achieve molecular-level dispersion in a high polymer material, and plays an efficient flame-retardant role. The flame retardant has a gas-phase and condensed-phase dual-phase flame retardant effect: in the gas phase, the effects of dilution and free radical capture are exerted; and in a condensed phase, char formation can be promoted and a barrier effect can be exerted. In addition, due to the existence of organic silicon, a compact carbon layer with a specific-Si-O-bond or-Si-C-bond of siloxane can be generated during combustion, the protection effect of oxygen isolation and heat insulation is achieved, and the condensed phase flame retardant effect is enhanced. The phosphorus-silicon type Schiff base derivative flame retardant has a wide application prospect and can be applied to flame-retardant modification of polyurethane and epoxy resin.

The invention relates to the technical field of coatings, and discloses a modified epoxy heat-resistant flame-retardant coating and a preparation method thereof.The preparation method comprises the steps that flame-retardant modified halloysite nanotubes, deionized water, epoxy resin, boron phenolic resin, a defoaming agent and a flatting agent are mixed to be uniform and discharged, and the modified epoxy heat-resistant flame-retardant coating is obtained. Diethyl hypophosphorous acid ethylene oxide methyl ester and boric acid modified halloysite nanotubes react to obtain flame-retardant modified halloysite nanotubes, and the halloysite nanotubes and the organic flame retardant diethyl hypophosphorous acid ethylene oxide methyl ester have a synergistic effect, so that agglomeration of the halloysite nanotubes is avoided, migration of a small-molecule organic flame retardant is avoided, and the flame retardance of the halloysite nanotubes is improved. The boron phenolic resin, the flame-retardant modified halloysite nanotubes and the epoxy resin form a three-dimensional cross-linked thermosetting network structure, so that the hardness, wear resistance and impact resistance of the coating can be improved, and the obtained coating has excellent flame retardance and heat resistance.

The invention relates to the field of flame-retardant substances, in particular to a diisobutyl aluminum hypophosphite intercalated montmorillonite flame retardant as well as a preparation method and application thereof. The preparation method comprises the following steps: melting diisobutyl aluminum hypophosphite in a high-temperature internal mixer, and adding montmorillonite for internal mixing and blending; performing high-speed stirring on the kneaded powder subjected to internal mixing in a high-speed mixer, and performing spray grafting on a silane coupling agent; grinding the silane coupling agent grafted diisobutyl aluminum hypophosphite intercalated montmorillonite into powder by using an airflow mill, and controlling the particle size to be 10-20 microns; polyimide (PI is a polymer containing an imide ring (-CO-NCO-1) repetitive group, is a faint yellow solid or powder in appearance, and has good flame retardance and low smoke formation without adding other auxiliaries, LOI can reach up to 47%, and the combustion grade is UL94-V-0 grade.

The invention is suitable for the technical field of MCA, and provides an MCA / PA6 flame-retardant composite material and a preparation method thereof. Comprising the following components in parts by weight: 50-60 parts of MCA, 15-20 parts of PA6, 15-25 parts of long glass fiber, 3-8 parts of metal hydroxide, 0.5-1.5 parts of titanium dioxide, 0.3-0.6 part of an antioxidant, 1-2 parts of nano silicon dioxide, 1-3 parts of zinc molybdate, 2-5 parts of aluminum hypophosphite, 1-2 parts of silicone resin, 0.5-1 part of carbodiimide and 5-8 parts of a toughening agent. The MCA / PA6 flame-retardant composite material disclosed by the invention combines the flame-retardant property of MCA and the excellent physical property of PA6, so that the flame-retardant property of the material is remarkably improved, and meanwhile, the original characteristics of light weight, good toughness, chemical resistance, good durability and the like of PA6 are maintained. By adding the long glass fiber, the metal hydroxide, the titanium dioxide, the antioxidant, the nano silicon dioxide, the zinc molybdate, the aluminum hypophosphite, the silicone resin, the carbodiimide, the flexibilizer and other components, the strength, the heat resistance and the flame retardant effect of the composite material are further enhanced.

The invention discloses a synthesis process of an environment-friendly halogen-free flame-retardant polyamide composite material, and belongs to the technical field of halogen-free flame-retardant polyamide composites.The synthesis process comprises the steps that firstly, the surface of an aluminum hypophosphite material is modified through a mechanical grinding method; meanwhile, an aluminate coupling agent and a rare earth aluminate coupling agent are respectively matched to react to generate a reticular cross-linked macromolecular structure, so that the compatibility of aluminum hypophosphite in a PA66 composite material system is improved; then, the modified aluminum hypophosphite prepared in the previous step and melamine polyphosphate are subjected to a synergistic effect to jointly serve as a flame retardant; the long glass fiber is used for reinforcing and toughening to improve the mechanical property of the composite material; finally, the environment-friendly halogen-free flame-retardant polyamide composite material is obtained. The technical problem of how to improve the environmental protection performance of the flame-retardant polyamide composite material is solved.

The invention provides an organic hypophosphite flame retardant as shown in a formula (I). Compared with the prior art, the flame retardant provided by the invention contains aryl, is high in stability, relatively high in phosphorus content and relatively high in flame retardance, can be used for flame retardance of various high polymer materials such as polyurethane, epoxy resin and unsaturated polyester, and can endow the polyurethane material with good flame-retardant stability and good mechanical properties especially when being applied to polyurethane.

The invention provides a polymer additive, a preparation method thereof and a polymer composition containing the polymer additive, and the preparation method comprises the following steps: carrying out free radical reaction on a hypophosphite aqueous solution and an antioxidant with ethylene in the presence of an initiator to obtain a diethyl phosphinate aqueous solution; mixing the diethyl phosphinate aqueous solution, the metal salt aqueous solution and the alkali liquor, and reacting under the condition that the pH value is 3.5-3.8 to obtain diethyl phosphinate metal salt slurry; mixing and stirring the diethyl hypophosphorous acid metal salt slurry and a flocculating agent to obtain a diethyl hypophosphorous acid metal salt flocculate, filtering, washing and drying to obtain the polymer additive. Through the design of the preparation method, the polymer additive with low acid value and high thermal stability can be obtained, the polymer additive is used as a flame retardant to prepare a polymer composition, injection mold scale can be reduced, the polymer composition has fewer water boiling precipitates, and the stability of the polymer composition under damp and hot conditions is improved.

The present invention provides a preparation method for high-content 2-trifluoromethyl-4-heptafluoroisopropyl aniline. In the presence of dithionous acid, a solvent, and a catalyst, 2-trifluoromethyl aniline and 2-bromoheptafluoropropane undergo a reaction and post-treatment to obtain high-content 2-trifluoromethyl-4-heptafluoroisopropyl aniline, wherein the catalyst is selected from phosphoric acid, pyrophosphoric acid, hypophosphorous acid, metaphosphoric acid, phosphorous acid, pyrophosphorous acid, hydrobromic acid, hydrogen bromide gas, hydrogen chloride gas or sodium bisulfite. The preparation method of the present invention is simple to operate, has mild chemical reaction conditions, achieves a primary reaction conversion content of 96% or above under good reaction conditions, has few post-treatment steps, requires no rectification, achieves a final product content of 98% or above, achieves a total reaction yield of 93% or above, is easy for industrial production, and has good prospects for application.

The invention relates to the technical field of ABS resin, and discloses modified ABS resin and a preparation method thereof.The modified ABS resin adopts a phosphorus-nitrogen flame retardant compounded by aluminum hypophosphite and melamine polyphosphate, dispersity is improved through surface modification of a silane coupling agent, efficient flame retardance is achieved, molten drops are inhibited, the influence on mechanical performance is reduced, and the flame retardance is improved. The low-temperature impact resistance is improved through the organic silicon modified acrylate core-shell toughening agent, meanwhile, rigidity loss is avoided, the tensile strength (larger than or equal to 45 MPa) and toughness are balanced, and the synergistic flame retardance and mechanical performance are optimized; nano titanium dioxide is subjected to double coating of stearic acid and silane and ultraviolet pretreatment, so that dispersity and ultraviolet shielding performance (UVA transmittance lt; the strength retention rate of the material is larger than or equal to 90% after the material is subjected to QUV aging for 1000 hours in combination with the hindered amine light stabilizer (HALS), the crystal structure is optimized through the rare earth beta nucleating agent, the thermal stability and surface smoothness of the material are further improved, and multifunctional compounding and weather resistance are improved.

The utility model discloses a bipolar membrane electrodialysis device for preparing high-purity hypophosphorous acid from sodium hypophosphite. The bipolar membrane electrodialysis device comprises a pure water deoxidation device, a sodium hypophosphite preparation tank, an acid liquid tank, an alkali liquid tank, a salt liquid tank, an electrode liquid tank and an electrodialysis membrane stack, the pure water deoxidizing device is respectively communicated with the sodium hypophosphite preparation tank, the acid liquor tank and the alkali liquor tank through deoxidized water liquid inlet pipes, the sodium hypophosphite preparation tank is communicated with the salt liquor tank, and liquid outlets of the acid liquor tank, the alkali liquor tank, the salt liquor tank and the electrode liquor tank are respectively communicated with corresponding liquid inlets of the electrodialysis membrane stack; a liquid outlet of the electrodialysis membrane stack is respectively communicated with the corresponding acid liquid tank, alkali liquid tank, salt liquid tank and polar liquid tank; the device has the characteristic of improving the preparation purity of hypophosphorous acid.