391 results about "Aromatic diamine" patented technology

The invention discloses a toughened epoxy resin and a curing method thereof, and relates to the technical field of epoxy resins, the toughened epoxy resin comprises the following components: 100 parts of an epoxy resin matrix, specifically a mixture of bisphenol A epoxy resin and alicyclic epoxy resin, 5-35 parts of a composite amine curing agent, and 5-20 parts of a nano toughening agent, in particular to core-shell rubber particles grafted with epoxy groups on the surfaces, the core layer of each core-shell rubber particle is cross-linked polybutadiene, the shell layer of each core-shell rubber particle is polymethyl methacrylate, 0.5-3 parts of an accelerant comprising a bi-component synergistic accelerant, 1-5 parts of an interface enhancer, and a mixture of gamma-glycidyl ether oxypropyl trimethoxy silane and a titanate coupling agent, a bisphenol A type epoxy resin and a specific proportion of alicyclic epoxy resin are combined to construct an epoxy resin matrix according to a mass ratio of 2: 1, the epoxy resin matrix is matched with a composite amine curing agent prepared by carrying out a special three-step reaction on long-chain polyether diamine, aromatic diamine and anhydride, and key parameters such as molecular weight, functionality and molar ratio of the components are accurately regulated and controlled.

The invention provides a preparation method of an h-BN / PI high-temperature-resistant anticorrosive coating, and relates to the technical field of polymer composites.The preparation method of the h-BN / PI high-temperature-resistant anticorrosive coating comprises the steps that under the protection of inert atmosphere, aromatic diamine containing impurity element five-membered rings and aromatic dianhydride containing ether bonds are taken and subjected to a polymerization reaction in a polar aprotic solvent, and the h-BN / PI high-temperature-resistant anticorrosive coating is obtained. A polyamide acid solution is obtained; performing ultrasonic-assisted liquid phase stripping on the micron-sized hexagonal boron nitride to obtain single-layer hexagonal boron nitride; adding the single-layer hexagonal boron nitride into the polyamide acid solution for multiple times, and uniformly stirring to obtain a hexagonal boron nitride / polyimide composite solution; and coating the hexagonal boron nitride / polyimide composite liquid on a to-be-coated surface, and carrying out gradient heating curing to obtain the h-BN / PI high-temperature-resistant anticorrosive coating. The h-BN / PI high-temperature-resistant anticorrosive coating based on interaction of multiple hydrogen bonds has relatively good high temperature resistance, relatively good resistance mechanical property and excellent corrosion resistance.

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 discloses a copolyimide film with low dielectric constant and low thermal expansion coefficient and a preparation method thereof, and the preparation method comprises the following steps: reacting 0.019-0.021 mol of aromatic dianhydride and 0.017-0.023 mol of diamine unit in 0.45-0.48 mol of solvent, then adding 0.0004 mol of end-capping reagent dissolved in 0.13-0.15 mol of solvent, and reacting to prepare polyamide acid with a main chain containing o-hydroxyl; the diamine unit comprises 10-40 mol% of a monomer with a main chain containing o-hydroxyl and the balance of aromatic diamine; performing film coating and thermal imidization on polyamide acid to prepare a polyimide film; and heating to carry out thermal rearrangement reaction on the o-hydroxyl to obtain the copolyimide film with the main chain containing the oxazole ring. The dielectric constant of the prepared copolyimide film is 2.7-3.0, and the thermal expansion coefficient of the copolyimide film is 19.5-26.5 ppm / K.

The invention relates to the technical field of nylon materials, in particular to hydrophobic high-strength transparent nylon as well as a preparation method and application thereof. According to the preparation method, 3, 3 '-dimethyl-4, 4-diaminodicyclohexylmethane (MACM), aromatic diamine and fatty diacid are taken as reaction monomers, and the novel transparent nylon is obtained by adjusting the dosage ratio of the monomers and further adjusting the preparation process (regulating and controlling the reaction process). The transparent nylon provided by the invention has the advantages of hydrophobicity, high strength and high light transmittance. The technical problem that existing nylon is high in water absorption rate is solved. The hydrophobic transparent nylon provided by the invention can be used under the condition of high humidity, and has higher safety and longer service life; therefore, the application field of the transparent nylon is expanded.

Disclosed are compositions comprising: a first component comprising an isocyanate-functional prepolymer; a second component comprising a polyol having an Mn greater than 1,000 g / mol; an aromatic diamine; and a filler in an amount greater than 50 percent by weight to 93 percent by weight based on total weight of the composition. Also disclosed are methods for treating a substrate comprising contacting a substrate surface with one of the compositions disclosed. Also disclosed are substrates comprising a coating formed from one of the compositions disclosed herein on a surface thereof. Also disclosed are batteries comprising one of the substrates disclosed herein.

The invention provides a polyamide composite material as well as a preparation method and application thereof, and the polyamide composite material comprises the following components in parts by weight: 30-60 parts of polyamide 66 resin, 10-30 parts of high char-forming resin, 4.5-8.5 parts of a red phosphorus flame retardant, 1-4 parts of a melamine derivative and 20-50 parts of glass fiber. The high char forming resin comprises aromatic polyamide; a molecular chain of the aromatic polyamide contains an aromatic diamine structural unit. According to the polyamide composite material disclosed by the invention, the oxygen index of the material can be improved by compounding specific types of high-char-forming resin, red phosphorus flame retardant and melamine derivative, meanwhile, the mechanical property and flame retardant property of the material are both considered, the properties are relatively balanced, and the polyamide composite material has the characteristics of no halogen, high performance, stable flame retardance and easiness in processing; the high requirement on the oxygen index of the material in the field of rail transit can be met.

The invention discloses a process method for preparing a multi-component aramid copolymer through continuous polymerization, and relates to the technical field of high polymer material preparation, and the process method comprises the following steps: S1, preparing a premix: weighing one or more aromatic diamine monomers according to a certain mass ratio, dissolving the aromatic diamine monomers in an amide solvent or a solvent compounded by amides and hydrotropy salt, and stirring to obtain the premix; uniformly stirring and dissolving in a reaction kettle under the protection of a nitrogen environment to form a premix; s2, low-temperature pre-polycondensation reaction; s3, low-temperature polycondensation reaction; s4, post-treatment: neutralizing, washing and drying the multi-element aramid polymer powder obtained in S3, and removing the solvent and the hydrotropy salt to obtain pure and uniform-particle brown yellow powder; or the obtained polymerization stock solution is neutralized, defoamed and filtered to obtain a spinning stock solution, the intrinsic viscosity of the processed brown yellow powder or spinning stock solution is larger than 4.5 dL / g, the polymer powder / polymerization solution can be used for preparing the multi-element aramid fiber through spinning, and the method effectively reduces the industrial production cost of the multi-element cyclic aramid fiber and improves the production efficiency.

The invention relates to the technical field of polymer dielectrics, and discloses a polyimide film preparation method, which comprises: (1) carrying out a condensation polymerization reaction on an alicyclic dianhydride monomer and an ortho-side group aromatic diamine monomer in an organic solvent to obtain a precursor solution; (2) forming a film from the precursor solution, and then carrying out drying and imidization reaction to obtain a polyimide film; the imidization reaction is carried out under a vacuum condition, and the imidization reaction is a temperature programming reaction and specifically comprises the following steps: preserving heat at 180-210 DEG C for 1-2 hours, raising the temperature to 240-260 DEG C, preserving heat for 1-2 hours, continuously raising the temperature to T, and preserving heat for 0.5-1 hour; wherein T = Tg-t, Tg is the glass transition temperature of the polymer, and t is larger than or equal to 10 DEG C and smaller than or equal to 20 DEG C. The polyimide film prepared by the preparation method disclosed by the invention has relatively high insulating property and heat resistance, so that the energy storage application temperature can reach 300 DEG C.

The invention provides benzocyclobutene-containing aromatic diamine and a preparation method thereof, and the preparation method comprises the following steps: dissolving 3-[1, 4-benzenediol]-bicyclo [4.2. 0]-octyl-1, 3, 5-triene and 4-nitrochlorobenzene in a first organic solvent, and reacting under an alkaline condition to obtain a benzocyclobutene-containing dinitro compound; and dissolving the benzocyclobutene-containing dinitro compound in a second organic solvent, and reducing in a hydrogen atmosphere to obtain the benzocyclobutene-containing aromatic diamine compound. The invention also provides a benzocyclobutene-containing aromatic polyamide polymer and a preparation method thereof. According to the linear aromatic polyamide and the cross-linked aromatic polyamide prepared by the invention, the content of benzocyclobutene in the structure can be adjusted according to a use scene, so that the mechanical strength, the thermal stability and the CTE are changed to adapt to different application requirements, and the linear aromatic polyamide is relatively good in solubility in an organic solvent, so that the linear aromatic polyamide is easy to process and relatively good in film-forming property.

The invention discloses a polyimide composite material and a preparation method thereof, and relates to the technical field of functional composites.The polyimide composite material is composed of hollow quartz fibers and silicon-containing polyimide resin, the fiber volume content of the polyimide composite material is 45%-60%, and the density of the polyimide composite material is 1.25-1.55 g / cm < 2 >; wherein the silicon-containing polyimide resin is formed by polymerizing a mixture of aromatic dianhydride, aromatic diamine and diamine containing a siloxane structure, and an end-capping reagent. The preparation method comprises the following steps: synthesizing a polyamide acid solution, preparing a prepreg by preimpregnation, performing by a vacuum bag method, performing hot-pressing curing and performing high-temperature post-treatment. Through collaborative innovation of the components and the process, the preparation method is simple, and the composite material has ultralow density, ultrahigh heat resistance, low dielectric constant and high strength and is suitable for the fields of aerospace, 5G communication, semiconductors and the like.

The invention provides a photosensitive polyimide photoresist and a preparation method thereof. The photosensitive polyimide photoresist comprises the following components in parts by weight: 20-50 parts of polyimide, 2-10 parts of a micromolecular monomer containing double bonds or triple bonds, 2-10 parts of a thiol monomer, 1-10 parts of a photoinitiator and 30-70 parts of an organic solvent. The polyimide is formed by polymerizing a magnolol-based bio-based diamine monomer, an aromatic diamine monomer and an aromatic dianhydride monomer. Compared with the prior art, the photosensitive polyimide photoresist prepared by the invention has good low-temperature curing and light pattern performance, and a cured film has good thermal and optical transmission performance and the like, can be applied to the fields of photoelectric devices, optical devices and the like, and also conforms to the development trend of green sustainable development.

The invention discloses an electrode for an alkali metal ion battery as well as a preparation method and application of the electrode. The electrode comprises 8-12 parts by weight of a dispersion binder, the dispersion binder is a polyimide polymer, the polyimide polymer is obtained by imidization of a polyamide acid polymer, and the polyamide acid polymer is obtained by polymerization of aliphatic diamine, aromatic diamine and aromatic dianhydride; the electrode for the alkali metal ion battery also comprises the following components in parts by weight: 75-85 parts of an active substance; and 8-12 parts of a conductive agent. According to the electrode for the alkali metal ion battery, the polyimide polymer serves as a binding agent during electrode preparation and serves as a dispersing agent of the conductive agent, the phenomena of agglomeration, sedimentation and the like of the conductive agent can be avoided, additional materials do not need to be added, increase of inactive substances is avoided, and the service life of the electrode is prolonged. Therefore, the energy density of the battery is improved, and the performance of the battery is optimized.

A polyurethane resin of the present invention includes a reaction product of a polyisocyanate component and a chain extending component, and the polyisocyanate component consists of a prepolymer composition including an isocyanate group-terminated prepolymer and a free polyisocyanate monomer; the isocyanate group-terminated prepolymer includes the reaction product of a bis(isocyanatomethyl)cyclohexane and a macropolyol having a number average molecular weight of 800 or more and 1800 or less; the isocyanate group concentration of the prepolymer composition is above 12% by mass and below 20% by mass; and the chain extending component is an aromatic diamine compound.

The invention provides a preparation method of a polyimide film with high light transmittance and good mechanical properties and the polyimide film. The preparation method of the polyimide film comprises the steps that a first kind of diamine with the first molar mass and a first kind of binary anhydride with the second molar mass are added into a solvent to be dissolved and react to obtain a first mixture, the first kind of diamine is fluorine-containing aromatic diamine, and the first kind of binary anhydride is rigid straight type dianhydride with a rigid coplanar structure; a second kind of diamine with a third molar mass is added into the first mixture, after stirring and dissolving, a second kind of dianhydride with a fourth molar mass is added, a polyamide acid resin solution is obtained, the second kind of diamine is fluorine-containing aromatic diamine, and the second kind of dianhydride is distorted dianhydride with a non-planar structure; adjusting the viscosity of the polyamic acid resin solution by using a solution of a second type of dianhydride to obtain a polyamic acid solution with target viscosity; and mixing the polyamide acid solution with a chemical imidization reagent, and imidizing to obtain the polyimide film.

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.

The invention discloses a high-temperature-resistant benzimidazolone polyamide imide battery binder as well as a preparation method and application thereof, and belongs to the technical field of battery materials. The high-temperature-resistant benzimidazolone polyamideimide battery binder with uniformly distributed amide segments and imide segments is prepared through a method for activating aromatic diamine on one side of trimethylchlorosilane and changing the activity of amino groups on the two sides, the comprehensive performance of the high-temperature-resistant benzimidazolone polyamideimide battery binder is excellent, the defects that a traditional binder is poor in heat resistance and insufficient in chemical stability are overcome, and the service life of the high-temperature-resistant benzimidazolone polyamideimide battery binder is prolonged. The introduction of high-polarity groups can improve the wettability and ion transmission capability of the electrolyte, improve the solubility of the electrolyte so as to facilitate electrode forming, and can also form strong chemical bonds or physical adsorption with positive and negative inorganic active materials during application, thereby reducing the structural damage in the cycle process and improving the electrochemical performance of the battery. The lithium ion battery electrode can keep a stable structure in a high-temperature environment, the thermal runaway risk caused by high temperature is remarkably reduced, and the application requirements of the lithium ion battery in a fast charging or high-temperature energy storage scene are well met.

The invention discloses a preparation method of a polyamide-imide-polyimide copolymer resin binder and a semiconductor element temporary packaging adhesive film, and the preparation method comprises the following steps: under the protection of inert gas, dissolving flexible long-chain aromatic diamine, siloxane diamine and 4, 4 '-dithio diphenylamine in a polar organic solvent, and stirring to obtain a mixed solution; the preparation method comprises the following steps: adding an acid-binding agent, uniformly stirring and mixing in an ice bath, adding trimellitic anhydride acyl chloride for reaction, heating to 15-45 DEG C, adding flexible long-chain dianhydride for reaction, adding an end-capping reagent for end capping, and diluting; adding a catalyst and a water absorbent into the diluted reaction liquid to carry out imidization treatment to obtain polyamide-imide-polyimide copolymer resin; diluting the polyamideimide-polyimide copolymer resin adhesive until the solid content is 15-25%, adding siloxane epoxy resin, and uniformly stirring and mixing, so as to obtain the polyamideimide-polyimide copolymer resin adhesive. The heat-resistant adhesive has excellent heat resistance and cohesiveness, and no adhesive residue exists in the stripping process.

The invention discloses a halogen-free resin composition and a high-Tg low-loss copper-clad plate prepared from the halogen-free resin composition. The halogen-free resin composition comprises the following raw materials: a bismaleimide polymer, aromatic diamine, benzoxazine resin, a phosphorus flame retardant, an inorganic filler, an imidazole catalyst and a solvent. According to the invention, through prepolymerization of the bismaleimide polymer, especially the oligomer and the aromatic diamine, the brittleness problem of common bismaleimide is solved, the modified bismaleimide has excellent toughness, and the problems of bismaleimide precipitation and board resin agglomeration when a large amount of bismaleimide resin is used are solved.

The invention belongs to the technical field of synthetic high polymer materials, and relates to water-soluble polyamide acid salt as well as a water-phase one-pot preparation method and application thereof. The preparation method comprises the following steps: completely dissolving an aromatic dianhydride monomer in water to obtain a first solution, completely dissolving an aromatic diamine monomer and an organic alkali in water to obtain a second solution, mixing the first solution and the second solution, carrying out a polymerization reaction, after the polymerization reaction is finished, adding an end-capping reagent, continuously stirring until the end-capping reagent is completely dissolved, and removing water to obtain a finished product. The water-soluble polyamide acid salt is obtained. According to the preparation method, water is used as a solvent, a single-step polymerization reaction is adopted, any subsequent purification treatment step is not needed, the production process is green and environment-friendly, the process is simple and convenient, the cost is low, and the preparation method is not limited by the feeding amount of aromatic dianhydride monomers and the scale of a reaction system. The viscosity average molecular weight of the finally prepared water-soluble polyamide acid salt is 8.0 * 10 < 3 >-2.0 * 10 < 4 > g / mol, the film forming effect is excellent, and the water-soluble polyamide acid salt can be used as sizing liquid.

The invention discloses an aromatic amine epoxy resin curing agent, a design method thereof, insulating epoxy resin and a preparation method thereof, and belongs to the technical field of insulation. At least two benzene ring structures are designed, and the benzene ring structures are connected through functional bridge bonds; an amino functional group is arranged at each of two ends of the designed structure; the ortho-position of the designed amino functional group is not provided with a high-electron-withdrawing substituent group; the aromatic amine epoxy resin curing agent is obtained; and the functional bridge bond is arranged at a 1, 4 or 1, 3 substitution position of the benzene ring structure. Polyaromatic diamine is used as a curing agent component of the epoxy resin, and a rigid aromatic structure is introduced into an epoxy main chain to enhance the thermal stability of the epoxy main chain and increase the glass-transition temperature; functional bridge bonds are introduced between benzene rings to break the conjugated structure of the benzene rings, so that the electrical performance is improved. And the high-temperature-stability and high-resistance insulating epoxy resin for the high-voltage direct current can be prepared. And the electrical performance of a key insulating part in the direct-current GIS / GIL under the action of a high temperature gradient and a high electric field can be improved.

The invention provides a polyimide film for optical fibers and a preparation method of the polyimide film, preparation raw materials of polyamide acid slurry for optical fibers comprise aromatic diamine, aromatic dianhydride, ester functional monomers, an organic solvent and a coupling agent, and the ester functional monomers comprise diamino-containing ester and / or ester containing dianhydride groups; the specific ester functional monomer is added into the preparation raw materials, and the coupling agent is added in a matched manner, so that a polyimide coating formed by coating the polyamide acid slurry for the optical fiber outside a bare optical fiber has good adhesion, flexibility, heat resistance and tensile property, can effectively protect the optical fiber, also has excellent chemical peelability, and is suitable for popularization and application. The optical fiber can be quickly dissolved or fused after being infiltrated into a chemical reagent, so that the optical fiber can be thoroughly stripped from a base material without damaging the base material, and connection and use of the optical fiber are facilitated.

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 provides a low-water-absorptivity aramid fiber lithium battery diaphragm, a preparation method thereof and a lithium ion battery, and belongs to the technical field of battery diaphragms. Specific fluorinated side chain aromatic diamine with relatively high activity is adopted, a fluorinated side chain is introduced into the aramid diaphragm through condensation polymerization of aromatic dicarbonyl chloride and the fluorinated side chain aromatic diamine, and the fluorine content is increased by controlling the chain length of a perfluorinated chain, so that the water absorption rate and the water affinity of the aramid diaphragm are obviously reduced, and the performance of the aramid diaphragm is improved. The water content of the diaphragm can be controlled within the requirement of a commercial diaphragm in a vacuum baking mode. Meanwhile, the low-water-absorption aramid fiber lithium battery diaphragm provided by the invention has low swelling property and high heat resistance of the aramid fiber polymer, and the prepared lithium ion battery has excellent capacity, cycling stability and safety performance.

The present invention relates to a polyol composition, comprising a polyol component (a) having a linkage A-containing moiety, wherein linkage A is selected from a group consisting of urethane linkage and urea linkage, wherein the polyol composition is obtained by reacting a polyurethane-containing material with a transesterification reagent containing at least 2 hydroxyl groups, and wherein the amount of amine in the polyol composition is not more than 2% by weight, based on the weight of the polyol composition. The present further relates to a process of preparing the polyol composition and use of the polyol composition. The polyol composition of the present invention has little or no hazardous aromatic diamine such as TDA and MDA, can be obtained directly from recycling polyurethane-containing materials, such as polyurethane-containing wastes, and can be used directly as the raw material for the production of new polyurethane materials.

The invention provides a normal-pressure drying preparation method and application of polyimide aerogel powder, and the method comprises the following steps: taking aromatic diamine and aromatic dianhydride as monomers, dissolving the monomers in an organic solvent, and carrying out condensation polymerization to generate a polyamide acid solution; the preparation method comprises the following steps: introducing metal ions into a polyamide acid solution, constructing a cross-linked network among molecular chains by a cross-linking agent, and preparing a polyimide solution through chemical imidization reaction; a polyimide solution is directly injected into absolute ethyl alcohol to shorten the gel aging time, rapid solvent exchange is carried out, the production cycle of the polyimide aerogel is remarkably shortened, and the obtained suspension is filtered and dried at normal pressure to prepare polyimide aerogel powder. The polyimide aerogel powder can be used for preparing functional slurry, a high-performance battery diaphragm is processed through a coating process, and the battery performance is remarkably improved. According to the invention, the slurry and the industrial spraying production technology are combined, the batch preparation of the large-area composite battery diaphragm can be realized, and the method has a wide application prospect.

The invention provides a polyimide film and a preparation method thereof, and relates to the technical field of polyimide film preparation. The preparation method of the polyimide film comprises the following steps: adding aromatic diamine and aromatic dianhydride into a polar solvent, and reacting to obtain polyamide acid resin; adding a dispersing agent and carbon black into a polar solvent to obtain slurry; adding the slurry into polyamic acid resin, and then adding aromatic dianhydride to obtain a polyamic acid resin solution B; adding aromatic diamine into the polyamic acid resin solution B to obtain a polyamic acid resin solution C, adding aromatic dianhydride to obtain a polyamic acid resin solution D, and adding an end-capping reagent to obtain a modified polyamic acid resin solution E; performing defoaming, coating and solvent removal treatment on the solution E to obtain a gel film, and performing imidization treatment to obtain a polyimide film; the film prepared by the invention has low water absorption and excellent insulating property.

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.