1844 results about "Poly ethylene" patented technology

In some embodiments, a cable can include an electrically conductive inner core. A first insulation layer can be disposed about the inner core. An electrically conductive layer can be disposed about the first insulation layer. A second insulation layer can be disposed about the electrically conductive layer. A first polymer jacket can be disposed about the second insulation layer. The first polymer jacket can include a first layer of armor strength members disposed therein. A second polymer jacket can be disposed about the first polymer jacket. The second polymer jacket can include a second layer of armor strength members disposed therein. An outer polymer jacket can be disposed about the second polymer jacket. At least one of the first polymer jacket, the second polymer jacket, and the outer polymer jacket can be formed from an aliphatic polyketone polymer, an ethylene-propylene copolymer, a polyolefin elastomer, a polypropylene, or a cross-linkable polyethylene.

The application provides a high-voltage cable preparation method and a high-voltage cable. The preparation method comprises the following steps: preparing modified polyvinyl chloride, wherein the modified polyvinyl chloride comprises polyvinyl chloride and a filler added into the polyvinyl chloride; taking 100 parts by weight of the polyvinyl chloride as a base material, and the filler comprises the following components in parts by weight: 1-2 parts of polyethylene, 2-3 parts of a filler, 2-3 parts of a lubricant and 2-5 parts of a toughening agent; extruding the modified polyvinyl chloride on the outer surface of a smooth metal sheath layer to form a modified polyvinyl chloride sheath, and the modified polyvinyl chloride sheath is bonded to the smooth metal sheath layer; and the smooth metal sheath layer is wrapped on the outer surface of a cable core. The high-voltage cable preparation method can greatly improve the flame-retardant performance of the high-voltage cable.

The invention relates to a particulate composition comprising, or substantially consisting of, urea, an inhibitor, preferably a urease inhibitor and / or a nitrification inhibitor, and an additive, wherein the additive comprises components (i), (ii), and optionally (iii): (i) one or more polyhydric alcohols; preferably one or more carbohydrates, preferably selected from monosaccharides, disaccharides, and oligosaccharides; (ii) a first polymer, preferably an amine-containing polymer; more preferably a polyvinylamine or a polyalkyleneimine; and (ii) optionally, a second polymer, preferably a polar polymer; more preferably a water-soluble polar polymer. The invention further relates to a process for producing the particulate composition, an additive for a particulate composition, and the use of the particulate composition as a fertilizer.

The invention discloses a cable insulating material which comprises the following components in parts by weight: 40-60 parts of low-density polyethylene, 20-30 parts of an ethylene-vinyl acetate copolymer EVA, 2-5 parts of a composite anti-aging agent, 5-10 parts of a core-shell structure nano composite modifier, 1-2 parts of a lubricant, 3-8 parts of a compatilizer, 20-30 parts of a composite flame retardant, 5-10 parts of a nano reinforcing agent and 2-4 parts of phenylsilane. The core-shell structure modifier strengthens interface bonding, and cooperates with the modified nano reinforcing agent to disperse stress, so that the mechanics and high and low temperature resistance are improved; the composite anti-aging agent inhibits multi-path aging and improves the aging resistance. The material has the advantages of excellent mechanical properties, high and low temperature resistance and outstanding aging resistance, and meets the insulation quality and efficiency requirements of cables in complex use environments.

The invention discloses a low-temperature vacuum microwave freeze-dried sinomenine hydrochloride preparation and a preparation method thereof in the technical field of pharmaceutical preparations, and solves the problems of long drying time, high energy consumption and poor product stability in the traditional freeze-drying technology. A vacuum microwave collaborative freeze-drying technology is adopted, microwave internal heating is achieved through a 2.45 GHz magnetron microwave generator and a rectangular waveguide tube under the conditions that the vacuum degree is 20-30 Pa and the plate layer temperature ranges from-40 DEG C to-35 DEG C, the microwave power density in the primary drying stage ranges from 0.3 W / g to 0.5 W / g, the microwave power density in the secondary drying stage ranges from 0.1 W / g to 0.3 W / g, and collaborative control over the microwave power, the vacuum degree, the temperature and the time is achieved in cooperation with a quaternary coupling precise control system. The preparation contains 50 mg of sinomenine hydrochloride, 100 mg of mannitol and 10 mg of sodium carboxymethyl cellulose grafted modified polyvinylpyrrolidone, the residual moisture is controlled to be 0.4-0.6%, the activity retention rate is 94-96%, and the drying time is shortened to 12-16 hours.

The invention belongs to the technical field of membrane separation, and particularly relates to a method for preparing a high-flux hollow fiber nanofiltration membrane based on interfacial polymerization, the obtained membrane and application. The method comprises the following steps: firstly, carrying out pre-adsorption treatment on a polyethersulfone hollow fiber ultrafiltration base membrane through a polyethyleneimine aqueous solution to form a reactive anchoring layer; then sequentially dipping in an aqueous phase solution containing piperazine, sodium phytate and nanoscale cellulose whiskers and an organic phase solution containing trimesoyl chloride and 5-isocyanate isopeptide acyl chloride for interfacial polymerization; and finally, carrying out heat treatment on the obtained primary composite membrane, and completing a gas-phase cross-linking reaction in a glutaraldehyde steam atmosphere. According to the method, the hollow fiber nanofiltration membrane with high flux, high selectivity, excellent chlorine resistance and pollution resistance is successfully prepared through a multi-stage strengthening process, and the hollow fiber nanofiltration membrane is suitable for the fields of drinking water purification, industrial wastewater reuse, material separation and the like.

The invention relates to the technical field of biological separation materials, and discloses an amine-functionalized magnetic nano composite material and application thereof in protein separation and purification. The material has a core-shell structure and comprises a magnetic ferroferric oxide nano core, an ordered mesoporous silicon dioxide intermediate layer and a covalent grafted polyethyleneimine functional layer. By controlling the matching relationship between the pore diameter of mesopores and the molecular size of the polymer and adopting a crosslinking strategy, the material has high magnetic responsiveness, rapid mass transfer performance and high-density surface amino groups. The material shows high adsorption capacity, rapid adsorption kinetics and good cycle stability in the protein separation process, and is suitable for enrichment purification and metal chelating affinity separation of protein in a biological sample. According to the invention, the technical problems of low protein adsorption capacity, slow dynamics and poor cycling stability caused by compact shell layer, non-uniform amino distribution and limited mass transfer of the existing amine functionalized magnetic material are solved.

The invention belongs to the technical field of membrane separation, and particularly relates to a low-pressure high-flux polyamide / polysulfone hollow fiber composite nanofiltration membrane and a preparation method thereof. The preparation method of the composite nanofiltration membrane comprises the following steps: dissolving sulfonated polysulfone, poly (1-vinyl-3-butylimidazole) bromide and polyvinylpyrrolidone to prepare a spinning solution, and spinning to obtain a base membrane; carrying out hydrophilic modification on the base membrane by using 1, 3-propane sultone; then, an aqueous phase solution containing poly (gamma-glutamic acid) and triethylene tetramine and an organic phase solution containing trimesoyl chloride and 3, 5-diaminobenzoic acid are subjected to interfacial polymerization in the inner cavity of the modified base membrane to form a polyamide separation layer; and finally, carrying out heat treatment to obtain the composite nanofiltration membrane. Through the synergistic effect of zwitterionic ionization of the base membrane and biomacromolecule construction of the separation layer, the mass transfer resistance of water is remarkably reduced, unification of high flux and high selectivity is achieved, and good structural stability is achieved.

The invention discloses application of sulfur quantum dot nanoparticles to improvement of plant waterlogging resistance. The invention provides sulfur quantum dot nanoparticles PEI-SQDs prepared from sulfur, sodium hydroxide, polyethylene glycol and polyethyleneimine. The sulfur quantum dot nanoparticles PEI-SQDs are simple in synthesis method, small in particle size, low in toxicity, low in price, simple to prepare, suitable for large-scale production, good in water solubility and good in biocompatibility; the compound has the capacity of removing active oxygen and ethylene in vitro, and can remove excessive active oxygen and ethylene in plants with waterlogging stress, relieve short-term waterlogging stress suffered by crops and recover growth and development of the crops when being applied to the plants with waterlogging stress; further, long-term waterflooding stress on the crops can be relieved, and the yield of the crops is increased; and the sulfur quantum dot nanoparticles are simple and convenient in use method and obvious in action effect.

The invention discloses an internal-acid and external-alkali type organic-inorganic hybrid molecular sieve catalyst as well as a preparation method and application thereof, and belongs to the technical field of heterogeneous catalytic materials and chemical processes. According to the catalyst, a hydrogen type Beta molecular sieve is used as an acidic inner core, polyvinylpyrrolidone (PVP) is used as an organic shell, and a unique inner-acid outer-alkali structure is formed. The preparation method comprises the following steps: hydrothermally synthesizing a hydrogen type Beta molecular sieve with a specific silica-alumina ratio, and then coating PVP through surface adsorption. The catalyst is used for catalyzing the condensation of methylal and trioxymethylene under mild conditions (40-70 DEG C and normal pressure) to prepare polyoxymethylene dimethyl ethers (DMMn). The PVP shell covers acidic sites on the outer surface of the molecular sieve to form an external neutral / weak base and internal strong acid microenvironment, so that the secondary side reaction of the product is effectively inhibited, the trioxymethylene conversion rate of more than 98% and the DMMn selectivity of more than 96% can be obtained in the reaction at 50 DEG C and normal pressure, the product distribution can be regulated and controlled, and the traditional Anderson-Schulz-Flory distribution limitation is broken through. The catalyst disclosed by the invention has the advantages of high activity, high selectivity, mild conditions and easiness in separation, and has a good industrial application prospect.

The invention relates to the technical field of pharmaceutical preparations, in particular to a solid dispersion-based sustained-release drug composite carrier as well as a preparation method and application thereof. The preparation method comprises the following steps: carrying out synergistic spray drying on double polymers (hydroxypropyl methylcellulose acetate succinate and polyvinylpyrrolidone-vinyl acetate copolymer) to form a solid dispersion; compounding with mesoporous silica and calcium silicate for localization, and spraying ethanol to activate pores; calcium stearate and magnesium stearate are sequentially added for lubrication; prefabricating a sustained-release skeleton master batch; and finally, mixing, rolling and forming. According to the method, through hierarchical structural design, the drug stability, the powder fluidity and the release controllability are remarkably improved, the method is suitable for industrial production of the dihydroergoline mesylate sustained release preparation, and a release curve is smooth and reliable.

The invention belongs to the technical field of new energy materials and bioelectrochemistry, and particularly relates to an iron-based multi-metal sulfide composite carbon anode material and a preparation method of the iron-based multi-metal sulfide composite carbon anode material. The preparation method is simple in process flow, convenient to operate, easy for large-scale production, wide in raw material source, low in cost and environment-friendly, and can be used for preparing the three-dimensional porous carbon matrix which is formed by foaming and carbonizing polyvinylpyrrolidone and is provided with interconnected carbon nanosheets. Through reasonable composition design and structural regulation, and optimization of metal ratio and vulcanization conditions, accurate regulation of material performance can be realized, electrochemical performance and biocompatibility are significantly improved, electricity generation performance and operation stability of a microbial fuel cell are improved, and good industrial application prospects are achieved.

The invention discloses a modified microfiltration membrane for enriching biological particles and a preparation method and application thereof, and belongs to the technical field of biological separation.The preparation method of the modified microfiltration membrane comprises the following steps that a mixed cellulose ester microfiltration membrane is provided and subjected to alkali liquor activating treatment; placing the activated membrane in a weakly alkaline buffer solution for balancing; the preparation method comprises the following steps: in a weakly alkaline buffer solution, firstly contacting the surface of the membrane with a tannic acid solution to carry out a first reaction, and then directly adding a polyethyleneimine solution to carry out a second reaction under the condition of not replacing a system, so as to form a phenol-amine cross-linked network on the surface of the membrane in situ; sodium cyanoborohydride is continuously added for reduction stabilization treatment, and the modified microporous filter membrane is obtained. The modified microporous filter membrane prepared by modifying the microporous filter membrane with tannic acid and polyethyleneimine can realize one-step synchronous enrichment of all negatively charged targets, and the problems of target loss, efficiency loss and the like caused by a multi-step process are avoided from the source.

The invention belongs to the technical field of biological medicine, and particularly relates to eutectic gel, a preparation method thereof and application of the eutectic gel in promoting mucous membrane drug delivery. The invention provides eutectic gel. The eutectic gel comprises a eutectic solvent and a polymer solution, the eutectic solvent comprises a hydrogen bond acceptor and a hydrogen bond donor; the polymer solution is selected from one or more of a gelatin solution, a polyvinyl alcohol solution, a polyethylene solution or a pyrrolidone solution. The eutecticevaporate gel provided by the invention can realize rapid and tight adhesion and continuous administration on mucous membranes which continuously secrete mucus, and has the following advantages: tight adhesion can be formed on mucous membranes with dynamically updated mucus, so that the residence time of an administration system on the mucous membranes is prolonged; and a drug delivery channel is established by penetrating through a mucous layer, so that the drug is efficiently and continuously delivered to mucous membrane tissues. The deep eutectic gel effectively solves the problem that an existing mucous membrane drug delivery system is low in drug delivery efficiency.

The invention discloses an anti-fouling curtain structure for water dredging engineering, and belongs to the technical field of environment protection of dredging engineering, the anti-fouling curtain structure for water dredging engineering comprises a floating body, an anti-fouling curtain and a vertical body, the floating body is arranged at the top end of the anti-fouling curtain, the vertical body is arranged at the bottom end of the anti-fouling curtain, and the anti-fouling curtain is geotechnical cloth; the geotechnical cloth is prepared from the following components in parts by weight: 100 to 150 parts of polyester, 20 to 50 parts of copolyester and 5 to 30 parts of inorganic filler, the copolyester is a copolymer of terephthalic acid, 5-sulfoisophthalic acid sodium salt, ethylene glycol and dihydroxyl-terminated polyvinyl imidazole, and the geotechnical cloth is further prepared by a post-treatment step. According to the invention, the copolyester composed of terephthalic acid, sodium 5-sulfoisophthalic acid, ethylene glycol and dihydroxyl-terminated polyvinyl imidazole and the inorganic filler are added into the polyester fiber, and the polyester fiber is modified through a post-treatment step, so that the alkali resistance and the antifouling property of the antifouling curtain are improved.

The present disclosure relates to a metallocene-catalysed multimodal polyethylene polymer (P), and to methods and uses of the multimodal polymer (P) of ethylene in film applications, and to a film including the disclosed polymer (P).

The invention discloses a MoO3 / TiO2 heterojunction material with a photocatalytic memory effect and application of the MoO3 / TiO2 heterojunction material in degradation of quinolone antibiotics, and belongs to the technical field of inorganic non-metallic material preparation, solar energy utilization and environmental protection. A molybdenum source precursor solution and a titanium source precursor solution are adopted to react, polyvinylpyrrolidone is used for modifying the surface of the material, the MoO3 / TiO2 heterojunction material is obtained, and the material can generate photochromic and photocatalytic memory effects under the pre-illumination effect. The memory effect provides continuous driving force for the catalytic reaction, and the activity of the material in the dark-state catalytic process is remarkably enhanced. The MoO3 / TiO2 heterojunction material disclosed by the invention shows excellent catalytic degradation performance in practical application, and particularly shows extremely high catalytic efficiency in the aspect of water pollution control.

The invention relates to a selective nanofiltration membrane as well as a preparation method and application thereof. The selective nanofiltration membrane comprises a support layer and a separation layer, the separation layer is obtained through interfacial polymerization of an oil-phase reactant and a water-phase reactant; the water-phase reactant comprises a negatively charged monomer and a positively charged monomer; the positively charged monomer comprises any one or a combination of at least two of polyvinylamine, polyethyleneimine, diethylenetriamine, water-soluble chitosan, quaternized polyethyleneimine, polyallylamine or triethylene tetramine. According to the method, monomers with different charges are added into a water phase, so that the nanofiltration membrane is wholly charged and neutral, the interception of sodium sulfate can be effectively reduced, the interception of antibiotics is increased, and the separation of the antibiotics and inorganic salts can be efficiently promoted.

The invention relates to the field of textiles, and particularly discloses a preparation process of antibacterial fibers, which comprises the following steps: S1, respectively drying and preparing polymer slices and an antibacterial agent; s2, performing melt spinning on the polymer slices and an antibacterial agent, performing air cooling, and then performing traction and winding to obtain antibacterial fibers; wherein the antibacterial agent is prepared by mixing dodecyl trimethyl ammonium chloride, polyvinylpyrrolidone and core-shell type antibacterial particles according to the mass ratio of (0.4-0.5): (0.1-0.2): 1, the core-shell type antibacterial particles are prepared by loading nano-zinc oxide and nano-silver particles on intercalation modified montmorillonite and then forming a silicon dioxide coating layer through a sol-gel method, and the core-shell type antibacterial particles are prepared from the silicon dioxide coating layer through a sol-gel method. And carrying out spray drying to obtain the core-shell antibacterial particles. The preparation method has the characteristic of improving the antibacterial durability and uniformity of the antibacterial fiber.

The invention discloses a washable, wear-resistant and uvioresistant polyarylate fiber as well as a preparation method and application of the washable, wear-resistant and uvioresistant polyarylate fiber. The method sequentially comprises the following steps: carrying out surface activation on fibers by adopting a deep eutectic solvent, spraying a TiO2 / organic ultraviolet absorbent UV1130 compound solution to construct an anti-ultraviolet layer, and carrying out interfacial polymerization by utilizing polyethyleneimine and trimesoyl chloride to form a polyamide encapsulation layer. The polyamide film can firmly coat the ultraviolet screening agent and anchor the ultraviolet screening agent on the surface of the fiber, so that the ultraviolet resistance of the polyarylester fiber is remarkably improved, meanwhile, the polyarylester fiber is endowed with excellent durability, the UPF retention rate is still higher than 90% after 10 times of standard washing or 200 times of friction, and the polyarylester fiber has excellent washing resistance and wear resistance. The process is simple, green and efficient, and the prepared composite fiber has wide application prospects in the fields of outdoor protection, intelligent spinning and the like.

The invention discloses a high-strength radio frequency cable for retracting and releasing an antenna, and relates to the technical field of radio frequency cables, the high-strength radio frequency cable comprises a sheath, the sheath is a soft protection tube made of polyethylene, an anti-bending protection assembly is arranged in the sheath, and a signal conduction assembly is arranged in the anti-bending protection assembly; according to the invention, through cooperation of the first layer of braiding and the second layer of braiding, double-layer structure protection is provided for the cable, bending resistance and pulling resistance of the cable are improved, electromagnetic shielding protection is carried out for transmission of electric signals in the inner conductor layer, and anti-interference capability of the cable is improved; through cooperation of the signal conduction layer and the supporting layer, the structural strength of the inner conductor is enhanced, and the bending resistance and the pulling resistance of the inner conductor are improved. Through the above structure, the problems that when an existing high-strength radio frequency cable is used, the cable is easy to damage or the signal transmission capability is reduced due to repeated bending, and the cable is easy to generate electromagnetic interference in a strong magnetic environment are solved.

The application discloses a kind of corrosion and scale integrated fracturing fluid, and relates to fracturing fluid technical field.The fracturing fluid includes thickening agent, crosslinking agent, composite corrosion and scale inhibitor and water;The composite corrosion and scale inhibitor includes the first component and the second component with mass ratio of 3:0.5~1, wherein the first component is prepared by the reaction of polyethyleneimine, long-chain acrylate monomer, acrylic acid monomer and hydroxyethyl acrylate monomer, and the second component is prepared by imidazole compound containing a primary amine and glyoxylic acid.The corrosion and scale integrated fracturing fluid of the application has good compatibility between components, and at the same time, it has good corrosion and scale inhibition and anti-sloughing performance.

The invention discloses concrete with anti-freezing performance and a preparation method thereof, and belongs to the technical field of concrete. The invention aims to solve the problems that the porosity of an interface transition area is high, hydration products are easy to degrade and the anti-freezing and anti-permeation performances are insufficient under the working conditions of high altitude, low air pressure, strong ultraviolet rays and salt-freezing synergy of the existing large-dosage fly ash concrete. The concrete is prepared from the following components in parts by weight: 100 parts of cement, 100 to 150 parts of coal ash, 280 to 320 parts of fine aggregate, 1000 to 1200 parts of modified basalt coarse aggregate, 1.5 to 3.5 parts of polycarboxylic acid water reducing agent, 0.2 to 0.6 part of PEG (Polyethylene Glycol) coated chitosan quaternary ammonium salt microspheres, 0.05 to 0.25 part of chitosan grafted nano cerium oxide composite particles, 1.0 to 3.0 parts of bacillus pseudofirmus microcapsule-polyvinylpyrrolidone mixture and 0.03 to 0.12 part of trisodium citrate. Through the synergistic effect of all the components, the interface structure of the concrete is effectively optimized, the ultraviolet aging resistance, the salt-freezing synergistic damage resistance and the chloride ion infiltration resistance are improved, the high-altitude severe service condition is adapted, and reliable material support is provided for high-altitude infrastructure construction.

The invention discloses a polymer dry powder fracturing fluid and a preparation method thereof, and belongs to the technical field of oil and gas field yield increase. The preparation method comprises the following steps: adding polymer dry powder, modified fluorocarbon, polyvinylpyrrolidone and beta-cyclodextrin into a mixer, stirring and mixing for 20-40 minutes, then sieving with a 120-180-mesh sieve, and packaging to obtain the polymer dry powder fracturing fluid. Nano silicon dioxide is modified and then subjected to a copolymerization reaction with acrylic acid, acrylamide and 2-acrylamido-2-methylpropanesulfonic acid, and nano particles with rigidity and extremely high thermal stability are chemically bonded to a polymer molecular chain, so that thermal oxidative degradation and shear fracture of the molecular chain at high temperature can be effectively inhibited; the shear resistance and the high temperature resistance of the fracturing fluid are improved; the fluorocarbon chain segment in the modified fluorocarbon can significantly reduce the interfacial tension between the fracturing fluid and the inner wall of the pipeline and the formation fluid, and the drag reduction capability of the fracturing fluid is enhanced in cooperation with the uniform and stable viscosity characteristic of the polymer system.

The application discloses a functional carrier filler, a preparation method and application thereof. The functional carrier filler comprises a polyethylene carrier and a functional layer loaded on the surface of the polyethylene carrier; and the functional layer comprises amino graphene. The application fixes the amino graphene on the surface of the polyethylene carrier, so that the surface of the filler is rich in nitrogen functional groups capable of mediating electron transfer, the electron transfer of microorganisms is promoted, the biodegradation of antibiotics is strengthened, the specific surface area of the carrier is improved, and the biofilm is hung, the functional carrier filler is used as a suspended filler of a moving bed biofilm reactor, and is used in a post-denitrification MBBR process after sewage treatment, so that the denitrification rate is improved, the degradation of antibiotics is promoted, the use of carbon sources is reduced, and energy saving and emission reduction are facilitated.

A resin composition that contains: (A) a bio-polyethylene resin; (B) an ethylene-vinyl alcohol copolymer having an ethylene content of 20 to 60 mol %; and (C) at least one component selected from the group consisting of an ethylene-vinyl acetate copolymer, an acid-modified ethylene-α-olefin copolymer, an ethylene-unsaturated monocarboxylic acid copolymer, an ionomer of the ethylene-unsaturated monocarboxylic acid copolymer, an ethylene-vinyl alcohol copolymer having an ethylene content of 70 to 90 mol %, and a hydrotalcite compound. The resin composition employs a bio-polyethylene resin and yet can suppress gumming and provide a formed product having an excellent appearance.

The invention discloses an electromagnetic shielding film as well as a preparation method and application thereof. The electromagnetic shielding film comprises the following components: InZnSeyC and a conductive polymer, the conductive polymer is prepared from poly (3, 4-ethylenedioxythiophene) and polystyrene sulfonate; the electromagnetic shielding film prepared by the invention has enough flexibility, bendability and self-supporting characteristic. The composite film can keep stable in structure without additional support, and has potential application prospects in the fields of 6G communication, high-frequency electromagnetic wave interference solving, health protection, flexible circuit boards and the like.

The invention relates to the field of sheath materials, and discloses an anti-aging sheath material for an electronic wire and a preparation method thereof, the sheath material comprises low density polyethylene, an ethylene-vinyl acetate copolymer, an ethylene-octene copolymer, ethylene propylene diene monomer, a triazine ring derivative, ammonium polyphosphate, modified nano silicon dioxide and an auxiliary agent; according to the triazine ring derivative, N-butyl-2, 2, 6, 6-tetramethyl-4-piperidylamine reacts with cyanuric chloride to prepare a triazine ring monosubstituent, hydrazine hydrochloride is used as a bridging agent to react with the triazine ring monosubstituent, and the triazine ring derivative and piperazine are polymerized to prepare the triazine ring derivative. The modified nano silicon dioxide is prepared by enabling 3-(3, 5-di-tert-butyl-4-hydroxyphenyl) propionyl chloride and 4-propenyloxy-2-hydroxybenzophenone to react, and carrying out free radical polymerization on the reaction product on the surface of the nano silicon dioxide. The synergistic effect of mechanical property, thermo-oxidative aging resistance, ultraviolet aging resistance and flame retardant property is realized.

This disclosure provides a nano-silver powder and its preparation method, relating to the field of metal powder preparation technology. The preparation method of the nano-silver powder includes: dissolving a silver source in a first solvent to obtain a first solution with a concentration of 0.01M to 0.5M; dissolving a reducing agent, polyvinylpyrrolidone, and a polysaccharide-containing compound in a second solvent and adjusting the pH to 8 to 9 to obtain a second solution; adding the second solution dropwise to the first solution under stirring conditions at 15°C to 50°C, controlling the dropwise addition time between 30 min and 180 min to obtain a third solution; and sequentially subjecting the third solution to ultrasonic dispersion, centrifugal classification, washing, and drying to obtain the nano-silver powder. This disclosure can improve the quality of the nano-silver powder.

The invention belongs to the field of lithium ion batteries, and particularly relates to an aramid polymer coated lithium ion battery diaphragm and a preparation method thereof, the diaphragm takes a polyethylene porous base membrane as a support body, and the surface of the polyethylene porous base membrane is coated with a composite coating containing a para-aramid polymer, two specific modified compounds and aluminum oxide. The two key modified compounds are perfluorophenylimidazole lithium salt and tetracyanobenzene dicarboximide dimethyl ammonium respectively, and the preparation method is realized through step-by-step reaction of commercially available raw materials. The preparation method of the diaphragm comprises the following steps: carrying out corona treatment on a base membrane, synthesizing an aramid fiber glue solution at a low temperature, adding two modified compounds, dispersing the two modified compounds and aluminum oxide to form a coating solution, and carrying out coating, coagulating bath phase inversion, water washing and vacuum drying to obtain a finished product. The two modified compounds have a synergistic effect, so that the thermal stability, ionic conductivity and electrode interface compatibility of the diaphragm are remarkably improved, and the finally prepared diaphragm has excellent thermal dimensional stability and electrochemical performance and is suitable for high-safety and long-service-life lithium ion batteries.