49 results about "Polyoxymethylene" patented technology

This invention discloses a method for synergistic surface modification of tungsten-copper powder to inhibit the decomposition of polyoxymethylene (POM), belonging to the field of polymer material anti-degradation modification technology. This invention addresses the problem that tungsten-copper powder easily catalyzes the severe degradation of POM during PIM tungsten-copper feedstock mixing and injection molding, leading to poor feedstock flowability, injection instability, large fluctuations in product size and weight, and low yield. First, the tungsten-copper powder is activated by low-temperature plasma etching to construct a reaction interface. Then, a silica barrier film is prepared using tetraethyl orthosilicate as the silicon source and modified with fluorosilicone, loaded with a metal soap neutralizer, grafted with a hindered phenolic antioxidant, and simultaneously introduced with epoxy active groups to construct a multi-component synergistic degradation inhibition system. This invention, through multi-step synergistic modification, precisely controls the modification process, comprehensively inhibiting POM decomposition. When the modified powder is blended with POM, a capping reaction occurs, blocking the unzipping degradation pathway of POM, improving the compatibility of the filler and the matrix, and ensuring the continuous and stable preparation and injection molding of PIM tungsten-copper feedstock.

The present application relates to the technical field of chemical process equipment control, and particularly relates to a polyformaldehyde polymerization auxiliary agent feeding system, which comprises a collection module, a buffer module, a metering module, a control module, a conveying module, a blocking module and a connecting module. The collection module acquires auxiliary agent attribute parameters and environmental data in real time; the buffer module maintains a micro-positive-pressure inert environment through a nitrogen sealing unit to prevent material oxidation; the metering module generates high-precision data by monitoring quality changes using a liquid loss balance; the control module dynamically adjusts the conveying rate based on a fuzzy PID algorithm; the conveying module uses a micro gear pump to reduce internal leakage; the blocking module absorbs fluid pulsation through a pulse damping unit; and the connecting module has a flexible pipeline structure to block mechanical vibration transmission. The modules cooperate to realize the precise conveying of several milliliters to tens of milliliters of auxiliary agent per hour, improve the feeding stability and precision, and ensure the polyformaldehyde polymerization reaction effect.

The application discloses a preparation method of energy storage long-cycle COPNA carbon material, and belongs to the technical field of lithium battery energy storage materials, and is characterized by comprising the following steps: first, composite carbonaceous raw materials are heated to 100 DEG C, and after being uniformly stirred, a compounded crosslinking agent and a compounded catalyst are added, and the stirring is continued for 10-15 min until the mixture is uniformly mixed, and then a crosslinking reaction is carried out at 120 DEG C-160 DEG C, and the reaction time is 4-6 h, so that COPNA resin is obtained; the obtained COPNA resin is carbonized at 460 DEG C-520 DEG C, so that COPNA carbon material is obtained. The application has the beneficial effects that: oil slurry pitch, coking wax oil and ethylene tar are used as the composite carbonaceous raw materials, the proportion of the three is controlled to accurately control the polarizing structure proportion of the COPNA carbon material, the structural stability of the material is improved, and the long-cycle requirement is adapted; the COPNA carbon material can consider the conductivity and the regularity of the layered orientation by using the furfural-polyformaldehyde compounded crosslinking agent and the compounded catalyst, and the structure damage or the conductivity decline in the long-term cycle process is avoided.

This disclosure relates to the field of chemical production technology, and in particular to a production apparatus and method for trioxymethylene. The trioxymethylene production apparatus includes: a reaction unit, a separation unit, a first formic acid absorption unit, and a product distillation unit. The outlet of the reaction unit is connected to the inlet of the separation unit; the gas phase outlet of the separation unit is connected to the inlet of the first formic acid absorption unit; the outlet of the first formic acid absorption unit is connected to the inlet of the product distillation unit; and the liquid phase outlet of the separation unit is connected to the inlet of the reaction unit. The reaction unit is used to convert formaldehyde into trioxymethylene under the action of a catalyst. The separation unit is used to separate the gas phase product from the reaction unit into a liquid stream containing recycled formaldehyde and a gas phase stream containing trioxymethylene. The trioxymethylene production apparatus and method provided by this disclosure are used to remove formic acid, a byproduct in the trioxymethylene production process, and reduce equipment corrosion.

This invention relates to a polyoxymethylene-based halide composite solid electrolyte, comprising polyoxymethylene, lithium / sodium salt, halide, plasticizer, and organic solvent; the mass ratio of polyoxymethylene, lithium / sodium salt, halide, plasticizer, and organic solvent is 1:0.08~2:0.001~0.55:0.01~1:6~120. This invention introduces a suitable formulation ratio to achieve a balance between the mechanical strength and ion conduction of the solid electrolyte. Polyoxymethylene, as the main material, provides mechanical strength, ensuring the self-support of the structure, thermal stability, and inhibiting dendrite growth. Small amounts of halide, plasticizer, and organic solvent do not affect the overall mechanical strength and significantly improve lithium-ion migration efficiency, broaden the electrochemical stability window, and enhance ionic conductivity.

This invention discloses a method for preparing furanyl diisocyanate and its applications, relating to the field of organic polymer compounds. Under nitrogen atmosphere, furoic acid is added to concentrated sulfuric acid and mixed, followed by the addition of paraformaldehyde and a temperature-controlled reaction to obtain bis(5-formic acid-2-furan)methane. An organic base is added to a solvent containing bis(5-formic acid-2-furan)methane, and diphenyl azide phosphate is added dropwise to react and obtain bis(5-acyl azide-2-furan)methane. The bis(5-acyl azide-2-furan)methane is dissolved in an organic solvent and reacted to obtain furanyl diisocyanate. This invention provides a high-yield, high-selectivity one-step method for obtaining the intermediate bis(5-formic acid-2-furan)methane, shortening the synthetic route, improving synthetic efficiency, avoiding the use of sodium azide, increasing safety, and reducing production costs. The production of bio-based polyurethane is environmentally friendly, economical, and industrially applicable, and can be used to develop environmentally friendly coatings, adhesives, and sealants.

This invention relates to a weather-resistant polyoxymethylene (POM) automotive sun visor material and its preparation method, belonging to the field of polymer materials technology. The weather-resistant POM automotive sun visor material prepared by this invention possesses excellent mechanical properties, UV aging resistance, and color fastness. This invention synthesizes an aging-resistant additive containing phosphate ester groups, triazine rings, morpholine rings, and tert-butyl groups. This additive can simultaneously exert peroxide decomposition, UV absorption, free radical scavenging, and steric stabilization effects, achieving efficient and in-situ synergistic effects at the molecular scale, solving the problems of component separation and asynchronous action in traditional systems. Furthermore, the aging-resistant additive synthesized in this invention, due to its polarity matching, can form uniform and strong intermolecular interactions (such as hydrogen bonds) with the POM matrix, serving as a dynamically reversible physical crosslinking point. This effectively improves the material's rigidity and strength while enhancing impact toughness through an energy dissipation mechanism.

The application provides a preparation method of 3,7-dinitro-1,3,5,7-tetraazabicyclononane, comprising the following steps: 1) feeding a first material comprising urea and concentrated sulfuric acid and a second material comprising fuming nitric acid and concentrated sulfuric acid into a microchannel reactor to perform a first-stage nitration reaction, to obtain a first-stage nitration reaction liquid; 2) feeding the first-stage nitration reaction liquid into a first tubular reactor to perform a second-stage nitration reaction, to obtain a second-stage nitration reaction liquid; 3) feeding the second-stage nitration reaction liquid and water into a second tubular reactor to perform a hydrolysis reaction, to obtain a hydrolysis liquid; 4) feeding the hydrolysis liquid and a third material comprising polyoxymethylene and ammonia water into a third tubular reactor to perform a condensation cyclization reaction, to obtain 3,7-dinitro-1,3,5,7-tetraazabicyclononane. The preparation method has the advantages of high safety, less waste pollution and simple operation.

The present invention relates to isocyanate-terminated prepolymers based on polyoxymethylene-polyoxyalkylene block copolymers, to a process for their preparation, and to the use of these isocyanate-terminated prepolymers as isocyanate components in 1- and 2-component systems for coatings, adhesives and sealants.

This invention relates to a process for preparing compounds having formula (I): R 1 ‑C(=O)‑O‑CH2‑O‑C(=O)‑R 2 (I), where R 1 and R 2 Each of the terms represents an alkyl, cycloalkyl, or aryl group independently, wherein the alkyl, cycloalkyl, or aryl group is optionally substituted; the process includes step i) reacting the following substances: compound A selected from: trioxane, polyoxymethylene without a hydroxyl terminal group; compound (II): R 1 -C(=O)-O-C(=O)-R 2 (II); and perfluorosulfonic acid; wherein step i) is carried out at a temperature T1 of at least 50°C, wherein the molar ratio of compound (II) to compound A is 1:1 to 1.2:1.

This invention discloses the preparation of a high-efficiency paraformaldehyde sulfonic acid catalyst and its application in the catalytic synthesis of C14 secondary alcohols, relating to the field of olefin catalytic hydration technology. The catalyst is prepared by high-temperature polymerization of p-toluenesulfonic acid and paraformaldehyde under concentrated sulfuric acid catalysis. C14 olefins, the paraformaldehyde sulfonic acid catalyst, isopropanol, and deionized water are added to a reactor, and a catalytic reaction is carried out at a certain temperature. The product conversion rate is 0.46%, and the selectivity is >99%. The catalyst of this invention is simple to prepare, has a well-developed mesoporous structure and sufficient acidic sites, provides mild catalytic hydration reaction conditions, exhibits good olefin conversion and secondary alcohol selectivity, and is easily recoverable and reusable. The process is green and environmentally friendly, with high atom economy, and is beneficial for the industrial conversion and application of high-value utilization of Fischer-Tropsch olefins from coal-to-oil.

Provided is a polyacetal resin composition that can reduce wear of a metal component even if the metal component comes into contact with a component (molded article) made of said polyacetal resin composition when the component made of the polyacetal resin composition slides, and that has preferable mechanical strength.　A polyacetal resin composition according to the present invention contains (A) 70-95 mass% of a polyacetal resin, (B) not less than 4 mass% to less than 25 mass% of a glass-based filler, and (C) 1-10 mass% of a glycidyl group-containing copolymer including an olefin and a glycidyl (meth)acrylate as copolymerization components.

A sealing gasket (F), typically used in areas such as doors, windows, and vehicle bodywork to ensure a perfect fit between two surfaces, close the gaps between them, and prevent the passage of external factors such as air, water, dust, and noise, characterized in that; comprising: - A clip (30) made of POM (Polyoxymethylene) material, forming the skeleton of the gasket (F), to ensure the gasket (F) is securely fixed in its intended location and to provide a corrosion-resistant, lightweight, and long-lasting gasket (F), - A body (10) formed by extruding TPE (Thermoplastic Elastomer) around the POM (Polyoxymethylene), to provide the gasket (F) with an elastic and durable structure and to ensure sealing against external factors such as water, dust, and air, and including at least one filler cavity (12), - Polyurethane (PU) injected into the filler cavity (12) to enhance the elasticity and high memory retention of the body (10).

The present application relates to a polyformaldehyde-based composite solid electrolyte film, comprising the following raw materials: polyformaldehyde, oxide, sulfide, lithium / sodium salt, plasticizer and additive, and the mass ratio of polyformaldehyde, oxide, sulfide, lithium / sodium salt, plasticizer and additive is 1:0.0005-0.6:0.0005-0.6:0.01-2.4:0.01-2:10-40. The present application also discloses a preparation method of the polyformaldehyde-based composite solid electrolyte film. Through unique component design, the present application realizes the complementary and synergistic effect of the material at the molecular scale, improves the interface stability, takes into account the wide working voltage window and high ion transmission rate, and effectively inhibits the anode side dendrite growth and penetration, and improves the processability of the material.

Provided is a polyformal resin containing a structural unit represented by formula (UN1) and a terminal structure having a vinyl group, the terminal structure being present at both ends. In formula (UN1): Ux is a single bond or a divalent group; R1 and R2 are each independently substituents; m is 0, 1, 2, 3, or 4; n is 0, 1, 2, 3, or 4; and * represents a binding site.

The present application relates to the technical field of catalyst, in particular to a synthesis method of active site adjustable bimetallic catalyst.The synthesis method of active site adjustable bimetallic catalyst comprises the following steps: synthesizing ligand;preparing bimetallic complex;limiting domain pyrolysis carbonization.The present application first takes p-tert-butylphenol, polyformaldehyde and bis(2-pyridylmethyl)amine as raw materials, reacts in a mixed solvent to synthesize ligand Hbpbp, then sequentially reacts with metal salt in methanol by a stepwise coordination method to construct homonuclear or heteronuclear bimetallic complex, finally uniformly mixes the complex with carbon black and dicyandiamide, and performs programmed temperature carbonization under inert atmosphere to prepare bimetallic catalyst with atomic level dispersion structure, realizes accurate anchoring and stable loading of bimetallic sites on the carbon carrier, and not only has high activity and stability in electrocatalytic carbon dioxide reduction reaction, but also can efficiently activate peroxymonosulfate for pollutant degradation.

This invention provides a method for preparing deuterated paraoxymethylene. Specifically, this invention provides a method for preparing deuterated paraoxymethylene comprising the following steps: (S1) deuteration of dibromomethane; (S2) synthesis of deuterated methylene diacetate; and (S3) synthesis of deuterated paraoxymethylene.

A method for preparing a high-strength, high-conductivity copper alloy by injection molding belongs to the field of powder metallurgy copper alloy preparation technology. The method includes: S1, preparing 50-500 nm nanoscale ultrafine copper composite powder using a chemical co-precipitation method; S2, mixing the ultrafine copper composite powder obtained in step S1 with polyvinyl butyral (PVB), granulating the mixture, and passing it through a 600-mesh sieve to obtain near-spherical hydroxide coarse composite powder with a particle size ≤23 μm; S3, subjecting the coarse composite powder to hydrogen calcination and reduction treatment to obtain near-spherical atomically mixed copper composite powder with a particle size ≤23 μm; S4, kneading and granulating the powder with a polyoxymethylene binder to prepare a feedstock; S5, obtaining a high-strength, high-conductivity copper alloy after injection molding, acid removal, and sintering. This invention achieves atomic-level mixing of powders through a chemical co-precipitation-hydrogen reduction process, which significantly reduces the sintering temperature and increases the density. The sintering temperature is reduced by about 100 °C, and the product has a relative density of ≥98%, electrical conductivity of ≥85% IACS, thermal conductivity of ≥350 W / (m·K), and tensile strength of 540–620 MPa, exhibiting excellent overall performance.

This invention relates to the field of polymer materials technology, and discloses a flame retardant composition for glass fiber reinforced polyoxymethylene (POM), its preparation method, and its application. The flame retardant composition comprises: 100 parts of a main flame retardant expander, 2-10 parts of a synergist, 1-6 parts of a compatibility modifier, and 2-10 parts of a toughening agent. This invention also provides a glass fiber reinforced flame retardant POM material containing this composition and its preparation method. Through the synergistic effect of its components, this invention achieves a stable UL-94 V0 flame retardancy rating within a range of glass fiber addition amounts, and exhibits good processing performance. It is suitable for high melt index POM, solving the problems of poor compatibility between flame retardants and glass fiber and obvious processing defects in existing technologies.

To provide a polyacetal resin composition that can reduce wear on metal parts even when parts (molded articles) made of the polyacetal resin composition come into contact with metal parts during sliding, and that also has good mechanical strength. [Solution] The polyacetal resin composition of the present invention contains (A) 70% to 95% by mass of polyacetal resin, (B) 4% to less than 25% by mass of glass-based filler, and (C) 1% to 10% by mass of polyamide or polyamide copolymer.

The application discloses a kind of full biological base benzoxazine monomer modified rosin-based epoxy resin and preparation method thereof, comprising: vanillin, decanediamine, polyformaldehyde are reacted to obtain full biological base benzoxazine monomer;Full biological base benzoxazine monomer and 1,8-are added to solvent and reacted to obtain the Schiff base with amino;The Schiff base with amino and propylene pimaric acid diglycidyl ester are mixed uniformly, then poured into mould, then heated and cured to obtain full biological base benzoxazine monomer modified rosin-based epoxy resin.The full biological base benzoxazine monomer modified rosin-based epoxy resin obtained by the application has strong mechanical properties and good thermal stability, and also has excellent self-repairing, shape memory, recyclability, hydrophobicity and dielectric properties.

A polyoxymethylene polymer composition is disclosed, comprising a formaldehyde stabilizer package. This formaldehyde stabilizer package, containing at least two emission control agents, significantly and unexpectedly reduces formaldehyde emissions. The formaldehyde stabilizer package includes at least two emission control agents selected from benzoguanamine compounds, hydantoin, substituted hydantoin, amino acids, and alkylene ureas such as ethylene urea.

A method for producing a polyoxymethylene polyoxyalkylene copolymer, comprising reacting a polymer formaldehyde compound with an alkylene oxide in the presence of a double metal cyanide (DMC) catalyst, wherein the polymer formaldehyde compound comprises at least one terminal hydroxyl group and wherein the method comprises the steps of placing a suspending agent in a reactor and subsequently incrementally or continuously metering in the polymer formaldehyde compound into the reactor during the reaction is provided.

It relates to novel formulations of epinephrine that comprise polyoxymethylene alkyl ethers as a permeation enhancer, methods of administering the formulation, and uses thereof.

To provide a polyacetal resin composition that can reduce wear on metal parts even when parts (molded articles) made of the polyacetal resin composition come into contact with metal parts during sliding, and that also has good mechanical strength. [Solution] The polyacetal resin composition of the present invention contains (A) 70% to 95% by mass of polyacetal resin, (B) 4% to less than 25% by mass of glass-based filler, and (C) 1% to 10% by mass of a glycidyl group-containing copolymer having olefin and glycidyl (meth)acrylate as copolymer components.

This utility model relates to the field of cotton spinning spindle wing stabilization technology, and discloses a cotton spinning spindle wing stabilization device, including a spindle disc, a spindle rod body fixedly installed on the top of the spindle disc, and a spindle foot 1 fixedly installed on the bottom of the spindle disc. A threaded sleeve is fixedly installed at the bottom of the spindle foot 1, and a spindle foot 2 is installed on the external thread of the threaded sleeve. An installation cylinder is fixedly installed inside both the spindle foot 2 and the spindle foot 1. Rubber rings are fixedly installed on the upper and lower surfaces of the installation cylinder. Three reinforcing rings 1 are fixedly installed inside the installation cylinder. The reinforcing rings 1 and 2 are made of polyoxymethylene material (with excellent wear resistance, low coefficient of friction, and good self-lubrication), which makes them more wear-resistant and extends the service life of the contact point between the device and the spinning yarn. Secondly, the spindle foot 1 and the spindle foot 2 are assembled, and damaged parts can be replaced in a targeted manner, saving costs. The rubber rings absorb the slight vibrations generated when the spinning yarn contacts the reinforcing rings 1.

The application provides a method for comprehensive utilization of polyformaldehyde organic alcohol waste liquid resources, comprising the following steps: the polyformaldehyde waste liquid is sent into a kettle heater with stirring function; the kettle heater is used for pretreating the polyformaldehyde waste liquid by adjusting the stirring speed; the pretreatment generates gas phase which enters a separation tower, and meanwhile, solid flocculation and precipitation at the bottom of the kettle are discharged; light components distilled from the top of the separation tower are condensed by a condenser, and then the components are detected by an online analyzer; the online analyzer switches the condensed liquid to a methyl formate storage tank, a benzene storage tank or azeotrope reflux tank according to the detection result; the content of the azeotrope reflux tank is sent into an extraction tank to add water as an extractant for extraction; after extraction, the mixture enters a water separation tank to be separated into layers; the upper benzene organic phase of the water separation tank is refluxed to the top of the separation tower, and the lower water phase is recycled back to the extraction tank; and the heavy components in the kettle of the separation tower are sent into a subsequent crystallization and filtration unit for treatment.

The utility model belongs to the powder sampling technical field, concretely relates to a kind of formaldehyde powder leakage sampling device of preventing polymerization, including the sampling storage box being communicated with storage tank, still including powder recovery tank, waste gas absorption tank, the sampling storage box is sequentially divided into coaxial upper cone cylinder, middle cylinder and lower cone cylinder from top to bottom, the upper cone cylinder is connected between the discharge port of storage tank by feed pipe, lower cone cylinder is connected between powder recovery tank by discharge pipe;The taper surface of the upper cone cylinder is provided with exhaust port, the hard anti-bending pipe is installed in this exhaust port, the anti-bending pipe is connected with a flexible exhaust pipe, the end of the flexible exhaust pipe is immersed below the liquid level of waste gas absorption tank;The junction of the middle cylinder and lower cone cylinder is provided with horizontal sieve plate, the sieve plate is provided with a plurality of hollow holes, the central position of the sieve plate is provided with recessed mounting groove, the open sampling bottle is clamped in the mounting groove;First valve, second valve are sequentially installed in the feed pipe from top to bottom, third valve is provided on the discharge pipe.The utility model is simple, low risk, low pollution.

The application relates to the technical field of detection devices, and discloses a detection device and method for the polymerization degree of paraformaldehyde, which are combined with a special paraformaldehyde polymerization degree detection device, are specially designed for the polymerization degree detection working condition of paraformaldehyde, can provide convenient conditions for the polymerization degree detection operation, and have higher overall practicability. The device comprises multiple reagent bottles, multiple raw material bottles, a main frame, a load component rotatably connected to the main frame, a processing component, and an operation component. The multiple reagent bottles are arranged in the processing component, and the multiple raw material bottles are arranged in the load component. The operation component comprises a mounting plate and two fixed pipes. The mounting plate is fixedly connected to the main frame, and the two fixed pipes are rotatably connected to the mounting plate. Lifting pipes are slidably connected in the two fixed pipes, sampling pipes are slidably connected in the two lifting pipes, primary springs are fixedly connected between the lifting pipes and the fixed pipes, and secondary springs are fixedly connected between the sampling pipes and the lifting pipes.

This invention discloses a zinc-based polyoxymethylene gel electrolyte based on weak interactions and its preparation method. Using bis(trifluoromethanesulfonyl)imide zinc (Zn(TFSI)2), dimethyl carbonate (DMC), and 1,3,5-trioxane monomer (TXE) as raw materials, DMC-POM-Zn(TFSI)2 is prepared via ring-opening polymerization. Zn(TFSI)2 acts as the zinc salt and initiator, while DMC acts as the solvent and plasticizer. A weak interaction is formed between DMC and the polyoxymethylene matrix (POM). The resulting DMC-POM-Zn(TFSI)2 exhibits an electrochemical impedance of 7.0–8.0 Ω and an ionic conductivity of 0.55–0.70 mS·cm. ‑1 It can cycle stably for more than 3000 hours, and the polarization voltage remains at 80-90 mV during the cycle.