159 results about "Phosphorus pentoxide" patented technology

The invention discloses a comb-type polyphosphate polymeric dispersant and a preparation method thereof, the dispersant is prepared by preparing a phosphate monomer from acrylate and phosphorus pentoxide, then copolymerizing the phosphate monomer with phenyl alkene or alkyl alkene, and finally adding alkali liquor for neutralization. A phosphate-polyether bifunctional side chain is introduced to a main chain, a phosphate group provides electrostatic repulsion, and a polyether group enhances steric hindrance, so that the dispersing agent can meet the requirements of strong adsorption and long-range stability at the same time, and a more durable and effective stabilizing effect is provided for a dispersion system.

The invention provides a thermal response self-ceramization fireproof coating and a preparation method thereof. The thermal response self-ceramization fireproof coating is prepared from the following raw materials in parts by mass: 3 to 10 parts of acrylic monomer, 3 to 10 parts of organic sulfonate, 1 to 4 parts of silane coupling agent, 0.5 to 3 parts of silicate ester, 4 to 6 parts of ceramic precursor, 3 to 6 parts of fluxing agent and 0.05 to 0.4 part of initiator. The fluxing agent comprises a component A and a component B, the component A is one of boric oxide, zinc borate or low-melting-point glass powder, and the component B is one of phosphorus pentoxide and ammonium polyphosphate. The silane coupling agent can be copolymerized with an acrylic monomer to construct a C-C main chain, the C-C main chain and silicate ester are subjected to hydrolytic condensation to form a Si-O-Si three-dimensional network, a chemical cross-linked skeleton is formed, and the chemical cross-linked skeleton can generate silicon dioxide at high temperature to participate in a ceramization reaction; the ceramic precursor and silicate ester can form a strong physical cross-linking effect, so that the fireproof coating with a chemical and physical double-cross-linked network can be formed, and the fireproof coating has excellent mechanical property and machinability at normal temperature.

The invention relates to a process for preparing a phosphor copper rod by using a phosphonate-amide composite purifying agent as a quenching aid, and belongs to the technical field of non-ferrous metallurgy. Phosphorus pentoxide and sodium carbonate are mixed and decocted into fused salt, the fused salt is cooled and ground and then added into a corundum crucible together with scrap copper to be rapidly heated, compressed air is blown in, and slagging-off is conducted after heat preservation and standing; blowing mixed gas into the melt for reduction refining; adding calcium boride into the melt for refining; the refined copper liquid is subjected to continuous casting and continuous rolling; rapidly immersing the phosphorus copper rod subjected to continuous casting and rolling into a quenching aid solution, and carrying out quenching treatment; and the quenched phosphor copper rod is blow-dried and dried, and the high-conductivity phosphor copper rod is obtained. The high-purity phosphorus copper rod prepared by the method is excellent in key indexes of copper content, phosphorus content and conductivity, and meets the expected requirements of high purity and high conductivity.

The invention relates to the technical field of modified carbon graphite materials, and particularly discloses an antioxidant modified carbon graphite material and a preparation method thereof, the antioxidant modified carbon graphite material comprises the following raw materials by weight: 30-34 parts of medium temperature pitch, 4-6 parts of modified silica sol and 10-12 parts of artificial graphite powder; from two aspects, firstly, the aluminum dihydrogen phosphate and the boric acid aqueous solution are added, the aluminum dihydrogen phosphate can promote the asphalt to form a denser and firmer glassy carbon structure during carbonization, and phosphorus pentoxide generated by decomposition of the aluminum dihydrogen phosphate and boron oxide generated by dehydration of boric acid can generate a glass phase with an anti-oxidation effect; secondly, core-shell particles are added, a shell layer of the core-shell structure is an aluminum hydroxide structure generated by hydrolyzing aluminum nitrate nonahydrate, and an inner core is epoxidized nano silicon carbide; through the synergistic effect of the two, the mechanical property and the oxidation resistance of the carbon-graphite material are improved.

The application provides a sulfide solid electrolyte and a preparation method thereof, and particularly relates to the technical field of secondary batteries. The sulfide solid electrolyte is a lithium phosphorus oxysulfide, and the chemical formula of the lithium phosphorus oxysulfide is Li7P3S 7.5+x‑5y O 3.5‑x+5y ; wherein, 0<=x<=3.5, 0<=y<=1.5, -7.5

This invention belongs to the field of high-performance materials and discloses a method for preparing a controllable PBO polymer. The steps are as follows: phosphorus pentoxide is dissolved in polyphosphoric acid to obtain high-concentration polyphosphoric acid; in reactor A, DAR and small-particle-size TPA are subjected to initial prepolymerization in the high-concentration polyphosphoric acid; the above materials are transported to reactor B, and large-particle-size TPA is added for secondary prepolymerization; final polymerization is carried out in a twin-screw extruder, and by adding an appropriate amount of DAR, a PBO polymer with controllable degree of polymerization is obtained; the PBO polymer is precipitated in water and dried to obtain the PBO polymer. This method first adds phosphorus pentoxide to polyphosphoric acid to prepare high-concentration polyphosphoric acid, avoiding the problems of poor powder dispersion, exothermic dissolution, and excessively high temperature that occur when adding phosphorus pentoxide during the polymerization reaction. Furthermore, by adding DAR monomer in the extruder to control the degree of polymerization of PBO macromolecules, the degree of polymerization is controllable, which has high practical value.

The application discloses a method for preparing high-temperature-resistant and anti-degradation well cementing material by using high-aluminum and high-silicon solid wastes, and the content of each component in the raw material is calculated according to the total mass of 100%, and the content of glass is 32-48%, the content of waste ceramic is 30-45%, the content of aluminum oxide is 15-25%, the content of boron trioxide is 1.1-4.8%, the content of alkaline earth metal oxide is 1.6-4.6%, the content of alkali metal oxide is 0.7-4.6%, the content of zirconium oxide is 0.8-5%, the content of zinc oxide is 0.4-2%, and the content of phosphorus pentoxide is 0.4-2%. The raw material is crushed, ground and grinded, the high-silicon aluminum precursor particles prepared by physical methods, chemical methods or the combination of both are pretreated, high-temperature spheroidized and surface-coated, so that the high-temperature-resistant and anti-degradation spherical additive product is prepared. The product has the excellent performances of high sphericity, good fluidity, small friction resistance, easy mixing, simple use and the like; the high-temperature resistance and anti-degradation are obvious under the well condition that the bottom hole static temperature is 150-300 DEG C, and the cement stone strength is obviously improved.

The invention relates to the technical field of chemical preparation, and discloses a preparation method of a phthalimide compound, which comprises the following steps: S1, raw material mixing: sequentially adding phthalic anhydride, a primary amine compound, p-toluenesulfonic acid and phosphorus pentoxide into a reaction container with a stirring device and a temperature control module, and stirring for 1-2 hours; adding ethanol as a solvent, and carrying out a stirring reaction; s2, curing: cooling the reaction liquid to 20-25 DEG C, slowly adding deionized water into the reaction liquid while stirring, standing, and separating out a solid product; a traditional dehydrating agent is changed into a low-cost green dehydrating agent combination, so that the cost loss is reduced, the stimulation effect is reduced, the catalytic activity is equivalent to that of p-toluenesulfonic acid by adding a new sulfonic group functional polymer, but the problems of volatility of liquid acid and equipment corrosion are avoided, a low-toxicity and low-cost solvent of ethanol is added, the toxicity is reduced, and the environment-friendly dehydrating agent is prepared. The preparation is safer, the cost is lower, and the applicability is wider.

This invention discloses a bioactive glass and its preparation method, belonging to the field of bioactive glass technology. It aims to solve the problems of insufficient synergistic effect between antibacterial efficacy and bone-promoting activity in existing materials, as well as the inability to monitor in vivo degradation processes in real time. The bioactive glass comprises 44-48 parts silica; 22-27 parts calcium oxide; 22-27 parts sodium oxide; 5-7 parts phosphorus pentoxide; 2-4 parts europium zinc complex; 10-20 parts chitosan; 1-5 parts lidocaine; and 2-5 parts dilute acetic acid solution. The addition of the europium zinc complex promotes bone formation and enhances antibacterial activity, achieving a highly efficient synergy between anti-infection and tissue regeneration. Simultaneously, it provides optical tracking capabilities, allowing for non-destructive real-time monitoring of the material's degradation behavior and tissue integration in vivo via fluorescence imaging. This invention offers superior material performance and a simple preparation process, providing an innovative solution for the repair of infected bone defects.

The application relates to the technical field of fine chemicals, in particular to a biomimetic amphoteric surfactant as well as a preparation method and application thereof; the preparation method of the biomimetic amphoteric surfactant comprises the following steps: reacting a fatty amine polyoxyethylene ether with a halogenated hydrocarbon to obtain a benzyl quaternary ammonium salt intermediate; cooling the benzyl quaternary ammonium salt intermediate, then adding phosphorus pentoxide to react; after the addition is completed, water is added, the reaction is continuously carried out, and the biomimetic amphoteric surfactant is obtained; the biomimetic amphoteric surfactant simultaneously integrates three characteristics of phosphate anion, polyether non-ion and benzyl quaternary ammonium salt cation, effectively solves the industry problem that traditional phosphates and cationic settling agents are incompatible, and is applied to metal processing fluid, can realize stable compounding with cationic settling agents while retaining excellent extreme pressure lubricity and hard water resistance, and can replace traditional extreme pressure agents such as environmentally-unfriendly chlorinated paraffin.

The application discloses a preparation method and system of sodium difluorophosphate. The preparation method of sodium difluorophosphate comprises the following steps: S100, in a water-free or low-water environment, a solid-phase reaction is generated between diphosphorus pentoxide and ammonium fluoride to obtain an ammonium difluorophosphate intermediate, and volatile substances generated in the reaction process are removed and recovered; S200, in a water-free organic solvent, the ammonium difluorophosphate intermediate obtained in the step S100 is reacted with a sodium salt to obtain sodium difluorophosphate. The preparation method of sodium difluorophosphate provided by the application uses diphosphorus pentoxide and ammonium fluoride as reaction raw materials to obtain an ammonium difluorophosphate intermediate, and then reacts to obtain sodium difluorophosphate. The obtained sodium difluorophosphate has high purity and few impurities. The preparation method of sodium difluorophosphate has the advantages of cheap and easily obtained raw materials, stable chemical properties, few by-products generated in the reaction, and easy recovery, and is a green and safe preparation method of sodium difluorophosphate.

The application discloses a production process of electroplating grade potassium pyrophosphate, which uses potassium carbonate and diaphosphorus pentoxide as raw materials, and adds a catalyst to react in a high-pressure reaction kettle. After the reaction is completed, water is added for dissolution, and the pH value of the slurry is controlled to be 9.0-10.0. After being filtered through a precision filter, the slurry is punched into a slurry storage tank, and the slurry storage tank is maintained at 75-95 DEG C. The slurry in the storage tank is punched into an evaporation and concentration device for concentration, and then the concentrated liquid is punched into a continuous crystallization device for continuous crystallization operation. After centrifugal treatment, the filtrate is recycled into the evaporation and concentration device. The potassium pyrophosphate crystals are subjected to vacuum drying treatment in a vacuum drying equipment, and then are packaged into finished products after being crushed and sieved. The potassium pyrophosphate crystals obtained by the application have high purity, less caking phenomenon, and stable and controllable product quality.

The invention discloses a collophanite dry sorting method based on combination of color sorting and a dense medium fluidized bed. According to the method, aiming at the defects of high environmental protection risk and insufficient single color sorting precision of existing wet sorting, efficient quality improvement of medium-low-grade collophanite is realized through a synergistic process of color sorting classification and dry-method dense medium fluidized bed enrichment: firstly, raw ore is crushed, concentrate, middling and tailings are obtained through two-stage color sorting classification, the concentrate is subjected to secondary color sorting, and the concentrate is subjected to secondary color sorting; the crushing size fraction is adjusted according to the content of phosphorus pentoxide, then an iron powder dense medium matched with the mineral particle size is adopted, and accurate separation is achieved through differentiated fluidization separation density. The whole process is free of water and chemical agents, the average grade of the concentrate reaches 20% or above, the phosphorus recovery rate is 80% or above, the environment-friendly requirements of ecological sensitive areas such as water sources are met, medium-low-grade resources can be fully utilized, the production cost is reduced, and the adaptability is wide.

A sustainable control release fertilizer and a producing method thereof are developed. The sustainable control release fertilizer comprises a natural char / struvite composite with different ratio of the natural char to struvite (0:100, 25:75, 50:50, 75:25). The natural char / struvite composites represent a phosphorus pentoxid content in a range of 16 wt% to 25 wt% which is more than a common phosphate fertilizer. Furthermore, a mole ratio of Mg2+:NH4+:PO4 3- in the sustainable control release fertilizer is 2:1:1. The sustainable control release fertilizer can enhance phosphorus uptake of at least one plant at early stage of growth due to its composition as well as the developed producing method of sustainable control release fertilizer is based on recovery of phosphorus from wastewater that has the good economic and environmental effects.

The invention relates to the technical field of preparation of fluorine-containing intermediates, and discloses a synthesis method for preparing 4, 4 '-difluorobenzophenone through a one-pot domino reaction. The invention aims to solve the problems of expensive raw materials, complex process, serious pollution, low yield and purity and the like in the prior art. According to the method, 4-fluorobenzoic acid and fluorobenzene are taken as raw materials, any one or more of trifluoromethanesulfonic anhydride, phosphorus pentoxide, trifluoroacetic anhydride or paraformaldehyde is taken as an acid catalyst under a solvent-free condition, and a target product is directly prepared through a one-pot reaction. After the reaction is finished, excessive fluorobenzene is recovered, a high-purity product is obtained through extraction, alkali washing, drying and concentration, and unreacted 4-fluorobenzoic acid can be recovered by acidifying a water phase. The method has the advantages of simple process, easily available raw materials, mild conditions and environmental protection, realizes the excellent effects that the conversion rate of 4-fluorobenzoic acid is greater than 99%, the product yield is greater than 95% and the purity is greater than 99%, and is suitable for industrial production.

The invention discloses a preparation method of phosphorus pentafluoride, which comprises the following steps: 1) mixing fluorine-containing inorganic salt and hydrogen-containing inorganic salt, and carrying out activation process treatment; and 2) adding phosphorus pentoxide into the system in the step 1) for reaction to generate phosphorus pentafluoride gas. The method has the advantages of low reaction temperature and high product purity, does not need to use high-toxicity and high-corrosivity hydrogen fluoride, and is environment-friendly, simple in process and suitable for industrial production.

The invention discloses a medium and low temperature wave-absorbing porous ceramic raw material and a preparation method thereof. The medium-low temperature wave-absorbing porous ceramic is prepared from the following raw materials in percentage by weight: 20 to 50 percent of magnetic loss phase, 20 to 45 percent of dielectric loss phase, 24.6 to 55.2 percent of low-temperature non-toxic flux, 5 to 10 percent of dual-mode pore forming agent, 0.07 to 0.125 percent of zinc oxide powder turbid liquid and 100 to 400 percent of citric acid solution, wherein the dielectric loss phase is zinc oxide powder modified carbon fiber and modified silicon carbide; the magnetic loss phase is flaky carbonyl iron powder or flaky iron-cobalt alloy; the low-temperature non-toxic flux comprises borax, silicon dioxide, zinc oxide and phosphorus pentoxide; the dual-mode pore-forming agent is formed by adding limestone powder or calcium sulfate powder into a mixture of rice husks and starch. The preparation method has the advantages of low raw material modification cost, simple process, environmental protection and the like, can be used for preparing the porous ceramic raw material with good wave-absorbing performance and temperature resistance, and can meet the requirements of military and civil fields on high-performance wave-absorbing materials.

The invention relates to a preparation method of furan-containing polybenzimidazole (PBI), in particular to a method for preparing furan-containing polybenzimidazole (PBI) by using bio-based furandicarboxylic acid (FDCA) as a diacid monomer instead of a traditional petroleum-based monomer and by using specific aromatic tetramine including 3, 3 ', 5'-tetracarboxylic acid (FDCA) as a diacid monomer. The novel polybenzimidazole polymer is synthesized by the following steps of: reacting 3, 3 '-diaminobenzidine, 3, 3', 4, 4 '-tetraamino diphenyl ether or 3, 3', 4, 4 '-tetraamino diphenyl sulfone at 150-160 DEG C for 2-4 hours under the protection of nitrogen in the presence of an ionic liquid solvent and a dehydrating agent phosphorus pentoxide, and reacting at 165-215 DEG C for 4-30 hours. The invention solves the problems of high processing difficulty, high cost and fossil raw material dependence of the traditional petroleum-based PBI.

The invention discloses a flame-retardant wood-plastic plate and a preparation method thereof, and relates to the technical field of wood-plastic plates. The flame-retardant wood-plastic plate prepared by the invention comprises modified polyethylene and modified wood flour, and the modified polyethylene is obtained by grafting a functional monomer to polyethylene and then reacting with phosphorus pentoxide; the modified wood flour is obtained by wrapping wood flour with polyether amine and then reacting with o-tolyl biguanide, and the prepared flame-retardant wood-plastic plate has good flame-retardant, antibacterial and anti-aging properties.

The invention relates to the field of inorganic non-metallic materials, and discloses a high-brightness long-afterglow luminescent ceramic material and a preparation method thereof.The material is composed of calcium fluoride, zinc sulfide, strontium sulfide, kaolin, quartz, albite, titanium dioxide, barium oxide, iron oxide and phosphorus pentoxide, a SiO2-Y2O3 crystal boundary regulation phase is introduced, the luminous efficiency and trap level distribution are optimized, and the luminous efficiency is improved. The preparation method comprises the steps of raw material ball milling, pre-sintering, cold press molding, three-section gradient hot pressed sintering, reduction annealing and polishing, and high densification and crystal grain controllable growth are achieved through staged temperature control pressurization. The initial brightness of the obtained material is greater than or equal to 800cd / m, the afterglow is greater than or equal to 11 hours, and the standard deviation of luminescence uniformity is lt; and the process is compatible with a conventional production line, the energy consumption is low, the cost is controllable, and the method is suitable for the fields of emergency indication, building decoration, intelligent wearing and the like.

The application relates to a bridge deck waterproof material and a preparation method thereof, which is prepared from the following raw materials in parts by weight: 15-22 parts of fluorosilicon type thermoplastic polyurethane elastomer, 65-72 parts of asphalt, 3-5 parts of cellulose nanocrystals, 5-8 parts of 2-naphthylamine-4,8-disulfonic acid, 0.8-1.5 parts of diaphosphorus pentoxide, 0.5-0.8 parts of polyphosphoric acid, 4-6 parts of vinyl hydroxyl silicone oil, 3-5 parts of SBR rubber powder, 1-2 parts of a coupling agent, 5-8 parts of reinforcing material, 1-3 parts of 1,3,5-triglycidyl-S-triazinetrione, 1-2 parts of (perfluoropropane-2,2-diyl)bis(4,1-phenylene)diacrylate, 3-5 parts of a plasticizer, 1-3 parts of an anti-aging agent, and 0.1-0.3 parts of an initiator. The bridge deck waterproof material has the advantages of large bonding strength, good low-temperature crack resistance, high-temperature resistance and aging resistance, excellent waterproof performance and long service life.

This invention discloses an environmentally friendly, high flame-retardant cable material and its preparation method, relating to the field of cable material technology. It comprises the following raw materials in parts by weight: 100 parts thermoplastic polyester elastomer, 10-15 parts benzene ring-containing hyperbranched polyborosilicate, 8-10 parts 3-tris(hydroxymethyl)methylamine-2-hydroxypropanesulfonic acid, 1-3 parts phosphorus pentoxide, 0.5-0.8 parts polyphosphoric acid, 3-5 parts melamine phosphate, 25-35 parts modified filler, 3-5 parts compatibilizer, 0.8-1.5 parts antioxidant, 0.5-0.8 parts lubricant, 4-6 parts plasticizer, and 1-2 parts light stabilizer. This cable material exhibits significant flame retardant effect, excellent mechanical and environmental properties, good aging resistance, and a long service life.

A glass-ceramic article comprises silica, lithia, phosphorus pentoxide, and zirconia in amounts that, when heat treated, provide a glass-ceramic including a lithium disilicate (Li2Si2O5) crystalline phase. The glass-ceramic may have high fracture toughness, transparency, hardness, and may be strengthen via ion-exchange.

The invention relates to a phosphorus-modified FER structure molecular sieve, which is characterized in that the mass content of phosphorus is 0.1-10% based on phosphorus pentoxide; after the molecular sieve is washed with water at 70 DEG C for 2 hours, the phosphorus content retention rate is not less than 60%, and the phosphorus content retention rate is defined as P2O5 after washing / P2O5 before washing in percentage by mass; the molecular sieve is obtained by contacting and dipping an FER structure molecular sieve with an aqueous solution of a phosphorus-containing compound of which the valence state of phosphorus is + 1 valence, drying, and roasting at 300-400 DEG C.

The utility model discloses a phosphorus pentoxide production tail gas purification system, which belongs to the field of chemical product production and comprises a washing liquid collecting tank, a primary washing tower, a fine washing tower, a production tail gas pipe, an exhaust pipe, a first washing liquid discharge pipe, a second washing liquid discharge pipe, a connecting pipe, a first liquid inlet device and a second liquid inlet device, the production tail gas pipe is communicated with the primary washing tower, the exhaust pipe is communicated with the fine washing tower, one end of the connecting pipe is communicated with the primary washing tower, the other end of the connecting pipe is communicated with the fine washing tower, the primary washing tower and the fine washing tower are located above the washing liquid collecting tank, and the first liquid inlet device is communicated with the primary washing tower and the washing liquid collecting tank. And the second liquid inlet device is respectively communicated with the fine washing tower and the washing liquid collecting tank. According to the utility model, not only is the overall occupied area reduced, but also the first washing liquid and the second washing liquid can be reused, and phosphorus pentoxide dust and the like can form phosphoric acid to be recycled.

The application discloses a kind of phosphogypsum road base water stable material and its construction method, by weight fraction, including calcined phosphogypsum 300~2000 parts, cement clinker 300~2000 parts, limestone 50~500 parts, toughening agent 1~10 parts, high-strength water-resistant agent 10~200 parts, sodium bentonite 50~100 parts, glass fiber 1~10 parts;The high-strength water-resistant agent is magnesium chloride, magnesium oxide, dimethyl chlorosilane is added with 1:1:0.05~0.5, the toughening agent is polyvinyl alcohol and EVA is mixed with 1:0.5~1 to form.The water stable material produced by using industrial by-product phosphogypsum calcined building gypsum as raw material has strong water resistance, high compressive strength and surface hardness, and is resistant to cracking caused by expansion;After premixing at construction site, road construction is carried out, the setting time meets the construction requirements, the water-soluble fluorine ion concentration of road surface is less than 3.50mg / L, water-soluble phosphorus pentoxide is not detected, the liquid leached under rainwater washing has no environmental pollution, the water stable material of the application enables the engineering of solid waste to be batched, and realizes the maximum resource utilization of phosphogypsum.

This invention relates to a composite catalyst, its preparation method, and its application. The preparation method of the composite catalyst includes the following steps: S1: providing a composite support containing zirconium oxide and oxides of non-metallic elements; S2: doping the composite support with gadolinium to obtain a composite doped support; S3: doping the composite doped support with yttrium and other metallic elements; wherein the oxides of the non-metallic elements include one or more of silicon dioxide, boron trioxide, and phosphorus pentoxide; and the other metallic elements include one, two, or three of holmium, erbium, and thulium. The composite catalyst prepared according to one embodiment of this invention can be used in the urea hydrolysis reaction, enabling the urea hydrolysis reaction to proceed at a relatively low temperature, and the catalyst exhibits a high high-temperature activity retention rate.

The invention discloses a method for measuring total phosphorus, polyphosphate, orthophosphorus and polymerization rate in an ammonium polyphosphate fertilizer, and belongs to the technical field of fertilizer detection.The method comprises the following steps that S1, an ammonium polyphosphate sample is weighed and recorded as m, the unit is g, and the ammonium polyphosphate sample is dissolved in water; s2, adjusting the pH value of the solution to 7.5-8.0 by using alkali; s3, titrating with a Mg < 2 + > standard solution to an end point; s4, alkali is added into the titrated solution to adjust the pH value to 8.1-8.5, titration is continued with the Mg < 2 + > standard solution, titration is excessive titration, the volume consumed again is recorded as V2, and the unit is mL; s5, filtering the mixed solution obtained after titration in S4, and washing the precipitate with water; s6, drying the precipitate at 110-118 DEG C until the weight is constant, and weighing to obtain the mass of the magnesium ammonium phosphate precipitate; and S7, calculating the content of orthophosphorus, the content of polyphosphate, the content of total phosphorus and the polymerization rate. The method provided by the invention can be used for rapidly detecting polyphosphate (based on phosphorus pentoxide), orthophosphorus (based on phosphorus pentoxide), total phosphorus pentoxide content and polymerization rate in the fertilizer-grade ammonium polyphosphate.

The present application relates to the technical field of polymer preparation, and provides a polybenzimidazole and a preparation method and application thereof.The present application forms a mixed solvent system by compounding PPA and MSA, improves the viscosity problem of a traditional single solvent system by the synergistic effect of a phosphorus pentoxide cosolvent, improves the solubility and mass transfer efficiency of the reaction system to diamine and diacid monomers, and lays a foundation for the full performance of polycondensation reaction; the mixed solvent system formed by compounding PPA and MSA not only solves the inherent defects of the pure PPA system, such as high viscosity, high reaction temperature and limited monomer diffusion, but also makes up for the short board of the pure MSA system, such as insufficient catalytic activity, realizes the synergistic balance of catalytic activity and mass transfer efficiency, completes the polycondensation under relatively low temperature conditions, significantly reduces the process energy consumption, greatly improves the product molecular weight and batch consistency, and the obtained polybenzimidazole can be used in the fields of proton exchange membranes, diaphragms and the like.

The application provides a novel polyphosphoric acid preparation method, which comprises the following steps: (1) ball milling P2O5 solid into P2O5 superfine powder with a required particle size; (2) taking the P2O5 superfine powder obtained in step (1) and water as raw materials, putting the raw materials into a reaction kettle according to a certain molar ratio, controlling reaction temperature, reaction time, stirring speed and reaction kettle pressure, and performing a polymerization reaction, so that a colorless transparent viscous liquid, i.e. polyphosphoric acid, is finally obtained.