151 results about "Aromatic diamine" patented technology

The invention discloses supercritical fluid foaming polyimide wave-absorbing foam and a preparation method thereof.The thermoplastic polyimide is prepared by the steps that aromatic dianhydride, aromatic diamine and aliphatic diamine serve as comonomers, polyimide acid is generated through solution polymerization, and then high-temperature cyclization is conducted; wherein the mole number of the aliphatic diamine accounts for 10-50% of the total mole number of the diamine, and the free volume and glass transition temperature of a molecular chain are effectively regulated and controlled by introduction of the aliphatic diamine; the wave-absorbing foam is prepared by taking polyimide as a matrix, doping 1-20wt% of wave-absorbing filler, and foaming for 1-3 hours in a supercritical carbon dioxide or nitrogen environment at the temperature of 180-220 DEG C and the pressure of 9-25MPa, through molecular structure design, the adsorption capacity and impact resistance of polyimide to carbon dioxide are remarkably improved, and the prepared foam has the advantages of light weight, high porosity, uniform foam structure and excellent heat resistance, can realize effective electromagnetic wave absorption in an X wave band, and is suitable for the fields of aerospace stealth and electromagnetic compatibility protection.

The invention provides a dye / ion separation membrane with pore diameter and charge coordinated regulation and control as well as a preparation method and application thereof, and belongs to the field of preparation of a double-layer ionic covalent organic framework (COFs) composite membrane. An aromatic polyamide ultrafiltration membrane is used as a base membrane, and a double-layer COFs membrane is constructed on the surface of the aromatic polyamide ultrafiltration membrane through a multi-time interfacial polymerization method. The first layer is a positive charge COFs layer formed by reacting a guanidyl monomer with 1, 3, 5-triformyl phloroglucinol (Tp); and the second layer is a negative charge COFs layer formed by reacting ionic aromatic diamine with Tp. By adjusting the type and concentration of the monomers, the pore diameter and charge distribution of the film layer can be synergistically regulated and controlled, and the double-layer composite film which is stable in structure and orderly stacked is constructed. The obtained membrane has molecular sieve separation and electrostatic regulation functions, can efficiently intercept organic dye molecules in high-salt printing and dyeing wastewater, and has high flux, high selectivity and good chemical stability.

Disclosed are compositions including a first component and a second component. The first component includes an isocyanate-functional polyurethane prepolymer. The second component includes a first difunctional polyol and an aromatic diamine. The composition also may include an accelerator. Also disclosed are substrates comprising a coating formed from one of the compositions disclosed herein on a surface thereof. Also disclosed are armor assemblies comprising one of the substrates disclosed herein.

The invention discloses a diamine monomer based on lignin chemical modification, a polyimide material and a preparation method and application thereof. The invention provides a diamine monomer based on lignin chemical modification and a preparation method thereof. The diamine is used for synthesizing polyimide. And copolymerizing the diamine monomer with an aromatic diamine monomer and a dianhydride monomer to prepare the polyimide material. Due to the addition of diamine, the free volume between polyimide molecular chains can be increased, so that the obtained polyimide material shows considerable dielectric properties in high frequency under the condition that the polyimide material does not contain fluorine, and the polyimide material has good insulating properties, which provides possibility for application to the field of microelectronics.

The invention discloses amino-terminated hyperbranched polyamide acid as well as a preparation method and application thereof. The amino-terminated hyperbranched polyamide acid is formed by polymerizing an aromatic anhydride monomer, an aromatic triamine monomer and an aromatic diamine monomer; the mole numbers of the aromatic anhydride monomer, the aromatic triamine monomer and the aromatic diamine monomer are a, b and c respectively, a: (b + c) = 1: 1-1: 1.5, and the proportion of b to c is any proportion. The amino-terminated hyperbranched polyamide acid disclosed by the invention not only has abundant terminal amino groups, but also contains a large number of polar groups such as ether bonds, imidazole rings, amide groups and carboxyl groups in molecular chains. Therefore, a stable water-based colloid emulsion can be formed in the presence of water and a small amount of organic solvent, other auxiliaries are not needed, and the interface performance and the mechanical performance of the composite material can be greatly improved.

The application discloses a kind of aromatic amine epoxy resin curing agent and its design method and insulating epoxy resin and its preparation method, belong to insulating technical field.At least two benzene ring structures are designed, and the benzene ring structures are connected by functional bridge bond;An amino functional group is respectively arranged at the two ends of the designed structure;High electron-withdrawing substituent group is not arranged at the ortho position of the designed amino functional group;Get aromatic amine epoxy resin curing agent;Functional bridge bond is arranged at the 1,4 or 1,3 substitution site of benzene ring structure.Multiple aromatic diamines are used as the curing agent component of epoxy resin, rigid aromatic structure is introduced into the epoxy main chain to enhance its thermal stability and improve the glass transition temperature;Functional bridge bond is introduced between benzene rings as breaking benzene ring conjugated structure, to improve electrical performance.Can prepare high-temperature stability and high-resistance high-voltage direct-current insulating epoxy resin.Help to solve the electrical performance of key insulating parts in DC GIS / GIL under the action of high temperature gradient and high electric field.

The invention relates to the technical field of polyimide film preparation, in particular to a high-light-transmittance polyimide film and a preparation method thereof.The preparation method comprises the following steps that aromatic diamine monomers are subjected to vacuum drying and then dissolved in an organic solvent, dianhydride monomers are slowly and dropwise added after the temperature is increased, a polyamide acid solution is obtained through segmented temperature control curing, and a polyimide film is obtained; performing vacuum defoaming on the solution, coating a substrate with the solution, performing gradient heating imidization treatment to obtain a film crude product, and performing plasma surface treatment and inert atmosphere annealing to obtain the high-light-transmittance polyimide film. According to the preparation method, conventional monomers are adopted, through optimization of drying, polymerization, defoaming, film forming, imidization and post-treatment process parameters, introduction of special structural monomers or external filler adding is not needed, the process is simple, the cost is low, the preparation method is suitable for large-scale production, and the prepared polyimide film is high in light transmittance at the wavelength of 550 nm and high in transparency. The optical uniformity, the surface flatness, the thermal stability and the mechanical property are excellent.

The invention discloses a tung oil-based non-isocyanate polyurethane photo-thermal anti-icing coating as well as a preparation method and application thereof, and belongs to the field of functional polymer materials. The method comprises the following steps: taking tung oil-based epoxy resin as a raw material, reacting with carbon dioxide to prepare tung oil-based cyclic carbonate, and reacting amino-terminated polydimethylsiloxane with terephthalaldehyde to obtain modified polydimethylsiloxane. And mixing tung oil-based cyclic carbonate, modified polydimethylsiloxane and a specific sulfur-containing aromatic diamine curing agent, spraying, and carrying out programmed heating curing to form the coating on the surface of the base material. A stable liquid-like layer can be formed on the surface of the coating, and the coating has extremely low surface energy and can obviously delay icing time. Meanwhile, the coating is endowed with efficient photo-thermal conversion capability through a D-pi-A molecular structure constructed by sulfur-containing diamine, and quick and active deicing can be realized under the irradiation of sunlight.

This polymer film 10 is characterized by comprising a first resin layer 11, a second resin layer 12, and a third resin layer, in that order. The polymer film is also characterized in that: the first resin film 11 forms one outermost layer of the polymer film 10; the first resin layer 11 includes a polyamide resin; the polyamide resin includes a copolymer polyamide that is a polycondensation product of diamine units and dicarboxylic acid units; the proportion of the number of aromatic diamine units to the total number of diamine units included in the polyamide resin that forms the first resin layer 11 is at least 75 mol%; the proportion of the number of isophthalic acid units to the total number of dicarboxylic acid units included in the polyamide resin that forms the first resin layer 11 is at least 22 mol%; the second resin layer 12 includes acid-denatured polypropylene; and the third resin layer 13 includes homopolypropylene.

Provided are a polyimide compound including a repeating unit having an aromatic diamine component having a specific structure in which a side-chain benzylic position is regioselectively brominated, a gas separation membrane having a gas separation layer containing the polyimide compound, and a gas separation module and a gas separation apparatus each having the gas separation membrane.

This invention relates to an aqueous polyimide / SiO₂ nanocomposite coating and its preparation method. The preparation method of the aqueous polyimide / SiO₂ nanocomposite coating includes: dissolving an aromatic diamine monomer in a system composed of water and an organic base; adding an aromatic dianhydride monomer in batches to react and prepare an aqueous polyamic acid salt solution; adding a silane coupling agent to the aqueous polyamic acid salt solution to react and then adding an orthosilicate ester for in-situ hydrolysis and condensation to prepare an aqueous polyamic acid / SiO₂ nanocomposite coating; coating the aqueous polyamic acid / SiO₂ nanocomposite coating onto a substrate surface, followed by drying and imidization treatment to obtain the aqueous polyimide / SiO₂ nanocomposite coating. The aqueous polyimide / SiO₂ nanocomposite coating of this invention has excellent heat resistance and adhesion properties, and can be widely used in high-temperature protective coatings and electronic packaging fields.

The invention relates to an imidazolium functionalized polyimide anion exchange membrane for diffusion dialysis acid recovery and a preparation method of the imidazolium functionalized polyimide anion exchange membrane, and belongs to the technical field of polymer functional membrane materials. The method comprises the following steps: firstly, carrying out condensation polymerization on a dianhydride monomer BPA-2a and an aromatic diamine monomer to prepare intrinsic microporous polyimide PI-6B containing a hexabenzyl structural unit; performing bromomethylation modification on the polyimide PI-6B-Br by adopting liquid bromine to obtain brominated polyimide PI-6B-Br; and carrying out nucleophilic substitution reaction through an imidazole compound, and introducing an imidazolium cation functional group on a polymer main chain to obtain the imidazolium functionalized polyimide anion exchange membrane. The obtained anion exchange membrane has high ion exchange capacity, high acid dialysis coefficient and excellent acid / salt separation factors, and has good application prospects in the field of waste acid diffusion dialysis recovery.

The invention relates to the technical field of membrane separation, in particular to a functional group regulated covalent organic framework (COF) membrane and a preparation method thereof, and relates to application of the membrane in selective separation of monovalent cations. The preparation method comprises the following steps: condensing a polyaldehyde monomer and aromatic diamine with different side chain substitutions on an interface through oil-water-oil three-phase interface micro-fluidic dripping to generate a two-dimensional COF nanosheet, carrying out ultrasonic dispersion, carrying out vacuum filtration, self-assembling on a porous substrate, and drying to obtain a continuous separation layer with the thickness of 50-150nm. The functional group can regulate and control pore channels and surface charges, flux and selectivity of monovalent cations such as Li < + > can be adjusted, effective separation is kept at the pH of 3-11, and the functional group is suitable for lithium salt extraction and electrolyte purification.

The present application relates to the technical field of insulating paint, in particular to a corona-resistant and high-wear-resistant modified polyimide insulating paint and a preparation method thereof. The corona-resistant and high-wear-resistant modified polyimide insulating paint comprises a polyamide acid resin and nano inorganic particles; the polyamide acid resin is synthesized from a dianhydride and a diamine, and the diamine includes a diamine containing a POSS structure and an aromatic diamine. The polyimide insulating paint prepared by the present application has the characteristics of corona resistance, high adhesion and high wear resistance, and can be used as an insulating paint for special motors and remains stable during long-time operation.

The application provides a polyimide insulating paint, preparation and application thereof. The polyimide insulating paint comprises a polyimide precursor, a crosslinking agent and a phase separation agent, the polyimide precursor is formed by reaction of aromatic diamine and aromatic dianhydride in an organic solvent, the aromatic dianhydride comprises 3,3',4,4'-diphenyl tetracarboxylic dianhydride with a molar content of 10-30%; the phase separation agent is an organic solvent with a boiling point higher than 170 DEG C, and the content of the crosslinking agent and the phase separation agent is respectively 0.1-10wt% and 10-50wt% of the total mass of aromatic dianhydride and aromatic diamine. The application also provides an electromagnetic wire comprising a conductor and an insulating layer coated on the surface of the conductor, the insulating layer is formed by coating and curing of the polyimide insulating paint of the first aspect. The polyimide insulating paint provided by the application has the advantages of low BPDA content, low cost, resistance to ATF oil water and high PDIV.

The invention relates to a synthesis method of an aminoacridine compound, and belongs to the technical field of organic synthesis. The synthesis method of the amino acridine compound comprises the following steps: reacting an aryne precursor derivative, polysubstituted o-aminobenzonitrile and fluorinion in the environment of acetonitrile and inert gas to obtain an aromatic diamine derivative, mixing the aromatic diamine derivative with a solvent, and reacting to obtain the amino acridine compound. And carrying out cyclization reaction under the action of acid to obtain the aminoacridine compound. The amino acridine compound is prepared by adopting a one-pot method, the process steps are simple, the experimental process is simplified, the raw materials are cheap and easy to obtain, and the product is easy to purify.

Provided is a two-part curing resin raw material that is curable at room temperature and has high strength, while having a long pot life. A two-part curing resin raw material according to an embodiment comprises a first liquid that contains an active hydrogen compound and a second liquid that contains a polyisocyanate, wherein: the active hydrogen compound contains an aromatic diamine having an alkylthio group; and the polyisocyanate contains an allophanate-modified product of an aliphatic polyisocyanate, which has a viscosity of 1300-3300 Pa·s at 25°C and contains 13-25 mass% of NCO.

The invention discloses a polyamide composite material as well as a preparation method and application thereof. The polyamide composite material comprises the following components in parts by weight: 90-150 parts of semi-aromatic polyamide; 30 parts of aliphatic polyamide; 60-90 parts of a reinforcing filler; wherein the semi-aromatic polyamide contains a structural unit derived from aromatic diamine and a derivative thereof and a structural unit derived from aliphatic dibasic acid; the aliphatic polyamide contains a structural unit derived from binary acid with the carbon atom number of 6-10 and a derivative thereof and a structural unit derived from aliphatic diamine, or a structural unit derived from lactam with the carbon atom number of 6-10 or aliphatic amino carboxylic acid; the average retention length of the reinforcing filler is 600 to 900 [mu] m. According to the polyamide composite material disclosed by the invention, specific semi-aromatic polyamide and aliphatic polyamide are compounded, and the dosage of each component is adjusted, so that the prepared polyamide composite material has relatively good fastening force and appearance performance.

This invention discloses a method for preparing a series of bismaleimide products, relating to the field of high-performance thermosetting resin monomer synthesis technology. The method includes a pre-reaction of maleic anhydride and aromatic diamine at a molar ratio of 2.0–2.2:1 under nitrogen protection at 60–90°C. The resulting amic acid intermediate is pumped into a twin-screw extruder. Irradiation is performed in the vacuum dehydration ring-closing zone (or imidization zone) using a 365 nm UV LED array, coupled with a 0.3–1.0 wt% benzophenone / triethanolamine photoinitiator system. The ring-closing reaction is completed at 110±5°C and a vacuum of -0.090 to -0.098 MPa, with a total residence time of 30–90 seconds, yielding bismaleimide products with an acid value ≤0.1 mg KOH / g and a ring closure degree ≥98.5%. Rapid product switching for a series of products can be achieved by changing different aromatic diamines. This invention eliminates the use of organic solvents, reduces energy consumption by more than 55%, and has a batch-to-batch acid value variation coefficient of less than 2%, meeting the requirements of electronic-grade packaging materials. Furthermore, the process conditions are fundamentally different from existing technologies, demonstrating significant technological advancements.

The invention discloses a method for preparing polyimide by reducing the imidization temperature of polyamide acid, which comprises the following steps: carrying out polymerization reaction on an aromatic diamine monomer and an aromatic dianhydride monomer in an organic solvent to generate polyamide acid, and then adding ZIFs to obtain a polyamide acid solution / ZIFs compound; the polyamide acid solution / ZIFs compound solvent is volatilized to obtain a polyamide acid / ZIFs compound, and then the polyamide acid / ZIFs compound is heated, so that the polyimide acid in the polyamide acid / ZIFs compound is subjected to imidization reaction to generate polyimide. By adopting the method to prepare the polyimide, the reaction temperature for generating the polyimide through imidization of polyamide acid can be obviously reduced, namely, the imidization temperature is reduced to 220 DEG C from the traditional imidization temperature greater than 300 DEG C, and the obtained polyimide has good thermal stability and transparency and can be applied to the high and new technical fields of display devices, photoelectrons, microelectronics, aerospace and the like.

This invention relates to the field of high-temperature resistant, low-dielectric polymer materials technology, and particularly to a diamine monomer containing an adamantane structure and its preparation method, polyimides and their preparation methods and applications, and polyimide films. The adamantane-containing diamine monomer has the following structure: wherein R1, R2, and R3 are the same or different, and each independently represents -H, C1-6 alkyl, halogenated C1-6 alkyl, methoxy, phenyl, -F, -Cl, or -Br. This invention introduces an adamantane alkyl group and a flexible ether bond into an aromatic diamine monomer, enabling the reaction of the diamine monomer with dianhydrides as a raw material for preparing polyimides to obtain polyimides with high solubility, high transparency, and low dielectric constant.

The invention discloses a dynamic covalent bond in-situ self-repairing composite nanofiltration membrane based on temperature response and a preparation method and application thereof, and belongs to the technical field of nanofiltration membranes. A functional layer of the nanofiltration membrane is a cross-linked network containing dynamic covalent bonds and formed by common reaction of aromatic diamine, a cross-linking agent and trimesoyl chloride, and the dynamic covalent bonds are imine bonds or disulfide bonds. When the surface of the membrane is damaged, dynamic covalent bond breakage and recombination can be triggered through mild heating at 60-80 DEG C, in-situ self-repairing of the membrane is achieved, and the repairing efficiency is larger than or equal to 90%. Compared with an existing beta-cyclodextrin system, pH adjustment is not needed, the elastic modulus is increased by 40% or above, the new membrane dye retention rate is larger than or equal to 98%, the method is suitable for printing and dyeing wastewater treatment and fine chemical engineering separation scenes, and the service life of the membrane can be remarkably prolonged.

This invention belongs to the field of polymer composite materials technology, specifically relating to a self-lubricating polyimide resin based on a perfluoroether bond network and carbon dot reinforcement, its preparation method, and applications. The invention involves mixing carboxyl-functionalized carbon dots, an ether-containing aromatic diamine, and a polar aprotic solvent to obtain a carbon dot-diamine pre-assembled system, which is then polymerized with a perfluoroaromatic dianhydride to obtain a linear polyamic acid solution. This linear polyamic acid solution is then reacted with a phenylacetylene-containing active end-capping agent to obtain a polyamic acid solution with a three-dimensional network structure. Finally, the polyamic acid solution with the three-dimensional network structure is cured in a protective gas atmosphere to obtain a self-lubricating polyimide resin. The self-lubricating polyimide resin provided by this invention achieves a synergistic improvement in load-bearing capacity, wear resistance, and structural stability under high temperature and high load conditions, and can be widely applied in aerospace high-temperature bearings, high-load sealing rings, wear-resistant coatings for extreme conditions, and high-temperature sliding components.

The present invention aims to provide a method for producing a silicone-modified polyimide resin having a desired structure without using amide-based solvents. Furthermore, the present invention aims to provide a method for producing a silicone-modified polyimide resin that does not use amide-based solvents and that yields a uniform silicone-modified polyimide resin even when it contains a high amount of silicone moieties, and in particular, a method for producing a silicone-modified polyimide resin that yields a uniform silicone-modified polyimide resin even when it contains a high amount of long-chain silicone moieties. [Solution] A method for producing a silicone-modified polyimide resin, A method for producing polyamic acid, comprising the steps of: reacting (A) a tetracarboxylic dianhydride, (B) a linear organopolysiloxane having amino groups at both ends, and (C) an aromatic diamine compound in (D) a solvent without amide bonds to obtain a solution containing polyamic acid; and subjecting the polyamic acid to a dehydration ring-closing reaction to imidize it to obtain the silicone-modified polyimide resin, wherein the amount of component (D) is 3.5 times or more the total mass of components (A), (B), and (C), and 15 times or less the mass of component (B).

The invention relates to the technical field of high-performance engineering plastics, in particular to polyimide as well as a preparation method and application thereof. The invention provides polyimide. The polyimide is prepared from the following raw materials in percentage by mole: 30-50% of an aromatic dianhydride monomer, 40-70% of an aromatic diamine monomer and 1-20% of a flexible diamine monomer, the flexible diamine monomer comprises bis (3-aminopropyl); the number average molecular weight of the flexible diamine monomer is 200 to 3000g / mol; the aromatic dianhydride monomer and the aromatic diamine monomer are polymerized to form a polyimide main chain, and the flexible diamine monomer is embedded into the polyimide main chain in a copolymerization form to serve as an enriched phase to form a dispersed soft phase domain. The polyimide has the advantages of intrinsic heat resistance and strength, and also has excellent fracture toughness.

The invention relates to the technical field of gas separation membranes, and discloses fluorine-containing copolyimide, a separation membrane and a preparation method and application of the fluorine-containing copolyimide and the separation membrane, and the fluorine-containing copolyimide contains structural units shown in a formula (1) and a formula (2); a is selected from a structural unit provided by trifluoromethyl diaminobiphenyl; m is 5 to 95; c is selected from a structural unit provided by an aromatic dianhydride monomer; n is 5 to 95; b is selected from any one of structural units provided by substituted or unsubstituted aromatic diamine; in (Y1) to (Y11), R1 to R21 are respectively selected from any one of H, halogen,-OH, amino, carboxyl, unsubstituted or substituted C1-C6 straight chain or branched chain alkyl and C6-C10 aryl;

The present disclosure relates to an organic polymerizable composition, and polymerized products and optical articles prepared therefrom. The composition comprises (a) an isocyanate-functional prepolymer and (b) an aromatic diamine having at least one primary amino group. The prepolymer (a) is prepared from a reaction mixture comprising: (i) a polyisocyanate component comprising (1) an aliphatic polyisocyanate having at least one primary isocyanate functional group and at least one secondary isocyanate functional group; and (2) a 4, 4 '-methylene bis (cyclohexyl isocyanate); and (ii) a polyol component. The composition further includes a photochromic compound, which may be present in the reaction mixture that forms the prepolymer. A method of reducing opacity of an optical article is also provided.

This invention provides a fabrication process for a negative electrode-free sodium metal battery and the battery itself. The fabrication process includes the following steps: preparing a positive electrode sheet; mixing an acrylate monomer, an aromatic diamine, and an initiator to obtain a first mixture, then adding a graphene oxide solution to obtain a second mixture; adding a liquid electrolyte and an ether to the second mixture to obtain a third mixture; separating the positive electrode sheet and the negative electrode current collector using a separator membrane and assembling them into a bare cell, then packaging it; filling it with the third mixture and sealing it; and finally, heating and polymerizing to form the battery. This fabrication process effectively suppresses sodium dendrites and, while maintaining the high capacity of the negative electrode-free sodium metal battery, also improves the battery's cycle performance and low-temperature performance.

The application belongs to the field of fine chemical industry, and proposes a synthetic route for preparing aromatic diamine from anisyl alcohol through esterification, carbon-carbon (C-C) coupling, nitration and reduction process. In the route, anisyl alcohol is first subjected to esterification reaction to obtain anisyl formate, the formate intermediate is further catalytically converted into a dimer, then the dimer is subjected to nitration to obtain an aromatic dinitro compound, and the nitration product is finally subjected to reduction to obtain the aromatic diamine. The route has high carbon yield and economic value.

The present application provides a kind of polyimide precursor, polyimide, its preparation method and application.The polyimide precursor has the repeat unit structure shown in formula I, the polyimide has the repeat unit structure shown in formula II:Wherein, R a It represents the residue of tetracarboxylic dianhydride component, and the residue of tetracarboxylic dianhydride component includes the residue of 9,9-bis(3,4-dicarboxyphenyl) fluorene dianhydride component;R b It represents the residue of aromatic diamine. The polyimide formed by the polyimide precursor, or the polyimide having the repeat unit shown in formula II has good solubility in various solvents, thereby giving it good processability; and the polyimide film provided by the present application has higher light transmittance, lower yellowness index, excellent thermal stability, higher glass transition temperature and good mechanical properties.