44 results about "BPDA" patented technology

The invention discloses a multilayer polyimide film as well as a preparation method and application thereof, belongs to the technical field of high-performance polyimide, and solves the problem that the thermal stability is not ideal when a PI film is applied to a flexible PI plate in the prior art. The method comprises the following steps: mixing ODA, GAPD and DMAc in an ice bath, mixing BPDA and TAHQ, and adding the mixture in batches to obtain a solution B; adding SiO2 aerogel into absolute ethyl alcohol, and carrying out ultrasonic treatment at room temperature to obtain a solution C; coating the solution B into a film shape, drying, coating the solution C on the film, drying, coating the solution B on the film again, and drying to obtain the polyimide film. The multilayer low-dielectric polyimide film prepared by the invention has the advantages of low dielectric, high temperature resistance, high interface compatibility and low water absorption.

The invention discloses a super-smooth, anti-corrosion and anti-coagulation hydrogel composite coating on the surface of a medical instrument as well as a preparation method and application of the super-smooth, anti-corrosion and anti-coagulation hydrogel composite coating, and the super-smooth, anti-corrosion and anti-coagulation hydrogel composite coating is a surface hydrogel composite coating formed by taking N-(3, 4-dihydroxyphenethyl)-2-benzoylbenzamide (BPDA) as a primer and grafting a hydrophilic polymer on the primer. BPDA is deposited on the surface of the substrate, then hydrophilic monomer surface graft polymerization is initiated by light, and a hydrogel coating is constructed on the surface of the BPDA substrate. The BPDA primer provides excellent corrosion resistance, the corrosion rate of a metal substrate is effectively reduced, and benzophenone derivatives with photoreaction activity on BPDA molecules can mediate firm combination of the hydrogel layer; after meeting water, a stable and compact hydrated layer is formed, the super-lubricating property is achieved, adhesion of protein and cells can be remarkably inhibited, and thrombus formation is effectively prevented. The anti-corrosion and anti-blood coagulation coating has excellent anti-corrosion and anti-blood coagulation properties, and is widely applicable to anti-blood coagulation and anti-corrosion surface modification in the fields of medical instruments and the like.

The NH2-UiO-66 (at) BTT-BPDA core-shell material is characterized in that NH2-UiO-66 is used as a core, and BTT-BPDA is used as a shell; the preparation method comprises the following steps: uniformly mixing zirconium tetroxide / 2-aminoterephthalic acid, DMF (Dimethyl Formamide) and acetic acid, heating, washing a solid product by using a mixed solution of methanol and DMF after heating, and drying to obtain NH2-UiO-66; the preparation method comprises the following steps: uniformly mixing NH2-UiO-66, benzotrithiophene tricarboxaldehyde and dioxane, heating, and washing a solid product by using tetrahydrofuran after heating, so as to obtain aldehyde NH2-UiO-66; the preparation method comprises the following steps: dissolving hydroformylated NH2-UiO-66, benzotrithiophene tricarboxaldehyde and (2, 2 '-bipyridyl)-5, 5'-diamine into a glass bottle filled with dioxane and glacial acetic acid; heating the glass bottle to obtain a brown product; and centrifuging the brown product, and washing the solid product with anhydrous tetrahydrofuran to obtain the NH2-UiO-66 (at) BTT-BPDA core-shell material. The NH2-UiO-66 (at) BTT-BPDA core-shell material is used for adsorbing harmful substances in industrial wastewater. The core-shell material prepared by the method is connected through dynamic carbon-nitrogen covalent bonds, has good structural stability, is rich in high-density benzene rings and pyridine rings, and has the advantages of high adsorption capacity, high adsorption rate, good selectivity, easy regeneration and the like on iodine and organic dyes.

The application discloses a synthesis method of 2,3,3',4'-biphenyl tetracarboxylic dianhydride, characterized in that 2,3-dimethylaniline is used as a starting raw material, 2,3-dimethylaniline diazonium salt is prepared through a diazotization reaction, then 2,3,3',4'-tetramethyl biphenyl is prepared through a coupling reaction of the 2,3-dimethylaniline diazonium salt and o-xylene under the catalysis of cuprous chloride, and finally 2,3,3',4'-biphenyl tetracarboxylic dianhydride is prepared through an oxidation reaction and dehydration to form anhydride. The coupling reaction in the synthesis method has good selectivity, 3,3,4',4'-tetramethyl biphenyl which is difficult to separate is not generated, high-purity a-BPDA can be finally obtained, and the coupling reaction in the synthesis method only needs to use low-cost cuprous chloride as a catalyst, so that the production cost is greatly reduced compared to a high-cost catalytic system in the prior art, and the synthesis method is more suitable for industrial mass production.

The present invention provides a polyimide film and a method for manufacturing the polyimide film, wherein the polyamic acid solution is obtained by imidizing a dianhydric acid component comprising two or more selected from the group consisting of benzophenone tetracarboxylic dianhydride (BTDA), biphenyltetracarboxylic dianhydride (BPDA), and pyromellitic dianhydride (PMDA), and a diamine component comprising paraphenylene diamine (PPD), wherein, based on a total content of 100 mol% of the diamine component, the content of paraphenylene diamine is 70 mol% or more and 100 mol% or less, and based on a total content of 100 mol% of the dianhydric acid component, the content of biphenyltetracarboxylic dianhydride is 50 mol% or more and less than 100 mol%, the dielectric loss rate (Df) is 0.003 or less, and the light transmittance at a wavelength of 550 nm is 15% or more and 50% or less.

The invention relates to a high-temperature-resistant epoxy resin adhesive and a preparation method thereof, and belongs to the technical field of adhesives. The adhesive comprises the following components in parts by weight: 100 parts of matrix epoxy resin, 15-22 parts of an anti-thermal debonding aid, 45-55 parts of a latent curing agent, 1.5-2 parts of a flatting agent and 28-36 parts of a reactive diluent, the preparation method comprises the following steps: carrying out click addition on mercaptoethylamine and diallylamine to prepare a diamine modifier, carrying out prepolymerization on BPDA and ODA, carrying out copolymerization on the diamine modifier as a bridging material and a prepolymer to prepare a modified matrix, and introducing an epoxy group to a side chain of a copolymer by epoxy chloropropane to prepare the anti-pyrolytic adhesion aid. The compatibility and dispersibility of the anti-pyrolytic adhesion auxiliary agent and the matrix epoxy resin are good, the anti-pyrolytic adhesion auxiliary agent is uniformly inserted and staggered in the adhesive layer to form a high-temperature-resistant interwoven network, the adhesive layer is fixed, adhesion failure caused by deformation of the adhesive layer at high temperature is reduced, and thus the high-temperature-resistant performance of the adhesive layer is improved.

This invention provides a flexible biomass RTP thin film material, its preparation method, and its application. The thin film material comprises a biomass substrate and luminescent functional molecules dispersed in the biomass substrate. The biomass substrate includes starch, sodium carboxymethyl cellulose, and a polyol plasticizer. The luminescent functional molecules are selected from at least one of ODQA, BPDA, TDCA, BDF, TPO, QBA, and BBA, and the loading amount of the luminescent functional molecules in the biomass substrate is 0.1wt% to 5wt%. The thin film material exhibits room temperature phosphorescence properties and an elongation at break ≥15%. This invention simultaneously achieves efficient room temperature phosphorescence (RTP) emission and excellent macroscopic mechanical flexibility in a biomass substrate.

The invention relates to the field of high polymer materials, in particular to an oil-water-resistant polyimide resin insulating material and a preparation method thereof.The oil-water-resistant polyimide resin insulating material comprises a polyimide precursor, core-shell structure inorganic filler and a DMAc / NMP mixed solvent, and the polyimide precursor is prepared from ODA, BPDA, PMDA and 2, 3, 4-triazole. 2, 2-bis (trifluoromethyl) benzidine is prepared through segmented feeding and polymerization; the core-shell filler takes silicon dioxide as a core and is grafted with an amino silane and fluoroalkyl silane double-coupling layer. The preparation method comprises the steps of core-shell filler synthesis, staged polymerization, ultrasonic dispersion and three-stage gradient curing. The material forms a gradient cross-linked network with a compact surface and a loose interior, after the material is soaked in ATF oil containing 0.5% of water at 155 DEG C for 2000 h, the weight change rate is smaller than or equal to 1.2%, the insulation resistance retention rate is larger than 95%, and the material has excellent oil-water erosion resistance, insulativity and mechanical property and has wide application prospects.

A polyimide composition comprising particles of a polyimide polymer derived from (i) ODA, (ii) PMDA, (iii) PPD, and (iv) BPDA monomers wherein when the polyimide composition consists of particles of a polyimide polymer, the polyimide composition has an apparent density of < = 0.25 g / cm3.

The present invention provides a polyimide fiber with ultra-high modulus and a preparation method thereof, and relates to the technical field of high-performance organic fibers. Two diamine monomers, 5(6)-amino-2-(4'-aminophenyl)benzimidazole (R3) and p-phenylenediamine (PPDA), are used to carry out polycondensation reaction with biphenyltetracarboxylic dianhydride (BPDA) in a solvent, N-methylpyrrolidone (NMP). The end-capping agent is used to control the dynamic viscosity of the polymerized slurry, and the plasticizing and stretching process of wet spinning and the multi-stage high-temperature stretching process are used to increase the molecular orientation degree inside the fiber while having ultra-high breaking strength, so that the polyimide fiber has an ultra-high elastic modulus. The diversity of polyimide fiber products is increased, and the downstream application market field is broadened. High-strength polyimide fibers can be continuously and stably produced, and the fibers have an ultra-high elastic modulus that the products on the market currently fail to achieve, and the force orientation degree inside the fiber molecules is greatly improved, so that the mechanical properties of the fibers are fully reflected.

The invention relates to the technical field of gas separation membranes, in particular to a cross-linked BPDA-based polyimide separation membrane for extracting helium from natural gas, which is prepared by copolymerizing diamine with TPEQ and BPDA, carrying out thermal crosslinking to synthesize a plurality of cross-linked polyimides, carrying out imidization treatment to prepare a membrane casting solution, and carrying out vacuum drying on the membrane casting solution to obtain the cross-linked BPDA-based polyimide separation membrane for extracting helium from natural gas. The crosslinking type polyimide separation membrane for extracting helium from natural gas is prepared through the prepared membrane casting solution, adopted diamine comprises DABA, ppd and ODA, and three polyimide materials with different polarities and crosslinking densities are synthesized by precisely regulating and controlling the chemical structure and network form of crosslinking type polyimide. Preferential permeation of He is promoted by optimizing the structural advantages of diamine; in this way, the technical problems that in the prior art, a separation membrane material is difficult to meet the requirements of high permeation flux and high selectivity at the same time, and the stability is insufficient under complex working conditions are solved.

The invention discloses black thermoplastic polyimide as well as a preparation method and application thereof, and relates to the technical field of polyimide. The invention discloses thermoplastic polyimide with a novel structure, the structure of the thermoplastic polyimide is as follows: diamine is ABABP and PNDA; dianhydrides BPTME and BPDA are used as raw materials. According to the preparation method disclosed by the invention, PNDA containing a chromophore group imino group (-N-H-) is selected, and the thermoplastic polyimide with black appearance is prepared under the condition that a black filler is not used. # imgabs0 #

An NH2-UiO-66@BTT-BPDA core-shell material takes NH2-UiO-66 as a core and BTT-BPDA as a shell; a preparation method comprises the following steps: uniformly mixing zirconium tetroxide / 2-amino terephthalic acid, DMF and acetic acid, heating, washing the solid product with a mixed solution of methanol and DMF after heating, drying to obtain NH2-UiO-66; uniformly mixing NH2-UiO-66, benzotriphene triformaldehyde and dioxane, heating, washing the solid product with tetrahydrofuran after heating to obtain aldehyde-based NH2-UiO-66; dissolving the aldehyde-based NH2-UiO-66, benzotriphene triformaldehyde and (2,2'-dipyridyl)-5,5'-diamine in a glass bottle containing dioxane and glacial acetic acid; heating the glass bottle to obtain a brown product; centrifuging the brown product, washing the solid product with anhydrous tetrahydrofuran to obtain the NH2-UiO-66@BTT-BPDA core-shell material. The NH2-UiO-66@BTT-BPDA core-shell material is used for adsorbing harmful substances in industrial wastewater. The core-shell material prepared by the method is connected through a dynamic carbon-nitrogen covalent bond, has good structural stability, is rich in high-density benzene rings and pyridine rings, and has the advantages of high adsorption capacity, fast adsorption rate, good selectivity, easy regeneration and the like for iodine and organic dyes.

The application provides a preparation method of a UiO-66-NH2-based mixed matrix membrane, which comprises the following steps: 3,3',4,4'-diphenyltetracarboxylic dianhydride is prepared by adding 4-chloro-N-methyl phthalimide, a catalyst A, a reducing agent and an additive into an aprotic solvent; then UiO-66-NH2 is added into the reaction system to obtain anhydride-capped UiO-66-NH2 (BPDA); UiO-66-NH2 (BPDA), BPDA and ODA are added into DMAC, a dehydrating agent and a catalyst B are added to obtain BPDA-ODA type polyimide containing UiO-66-NH2; and the BPDA-ODA type polyimide containing UiO-66-NH2 and DMAC are configured into a casting solution to obtain a mixed matrix membrane UiO-66-NH2 / BPDA-ODA-N. Compared with the traditional direct doping method for preparing the mixed matrix membrane, the preparation method greatly improves the doping amount of UiO-66-NH2, which makes the permeation flux of CO2 further improved while the selectivity of retaining CO2 is reserved, and the CO2 separation performance is more excellent.

The invention belongs to the technical field of high polymer materials, and discloses a method for preparing an intrinsic black material from epoxy resin modified polyimide prepared from a bio-based material. Bio-based furfural and eugenol are used as monomers to synthesize a diphenol monomer, and then the diphenol monomer is epoxidized to prepare an epoxy monomer. And finally, adding the black epoxy resin into a commercial PAA acid solution prepared from ODA and BPDA for polycondensation to obtain an epoxy modified polyamide acid solution, and preparing the black epoxy resin / polyimide composite material by a thermal method. The epoxy monomer with high absorbance is introduced, the black composite material can be prepared only by adding a small amount, and the method is simple and efficient. The prepared black epoxy resin / polyimide composite material is excellent in shading performance and heat resistance and has wide application value in the fields of electronic industry, aerospace, instrument communication and the like.

This invention discloses an amino-functionalized ZIF-8 modified polyimide composite film and its preparation method, belonging to the field of polyimide film technology. The process involves a binary copolymerization reaction of p-phenylenediamine (p-PDA) and biphenyl tetracarboxylic anhydride (BPDA) to obtain a polyamic acid (PAA) solution. Then, amino-functionalized ZIFs (ZIF-8-NH2) are ground and thoroughly mixed with a solvent. After ultrasonic extraction, the mixture is introduced into the aforementioned PAA solution to obtain a PAA / ZIF-8-NH2 composite liquid. After adjusting the molar ratio of the dianhydride and undergoing thermal imidization treatment, the amino-functionalized ZIF-8 modified polyimide composite film is obtained. This invention introduces ZIF-8, which possesses high porosity, large specific surface area, adjustable pore structure, excellent thermal stability, and low thermal conductivity, into the composite film preparation process. Based on this, the ZIF-8 is amino-functionalized, resulting in a composite film material with uniform filler dispersion, ultra-low dielectric constant, low dielectric loss, and excellent thermal insulation performance.

The invention relates to a chemical bonding type heterostructure photocatalyst based on a pyrenyl covalent organic framework as well as a preparation method and application of the chemical bonding type heterostructure photocatalyst based on the pyrenyl covalent organic framework. The catalyst is prepared from the following raw materials: 1, 3, 6, 8-tetra (p-aminophenyl) pyrene, 2, 5-dimethoxy terephthalaldehyde or terephthalaldehyde or 4, 4 '-biphenyldicarboxaldehyde and g-C3N4; the expression of the obtained catalyst is as follows: XTAPPy-DMTP-CN or XTAPPy-TPA-CN or XTAPPy-BPDA-CN, X is the mass fraction of TAPPy-DMTP-COF or TAPPy-TPA-COF or TAPPy-BPDA-COF, and the numerical range of X is 10 to 50 percent; according to the technical scheme, the interface driving force can be improved, the charge transfer path is optimized, and the photocatalytic performance of the material is further improved by introducing the pyrenyl unit and the oxidation-reduction active sites.

Provided is a multilayer polyimide film that is excellent in heat-resistance, low dielectric loss tangent, and dimensional stability. The multilayer polyimide film has: a layer of a heat-resistant polyimide; and a layer of a heat-bondable polyimide laminated on one surface or both surfaces thereof. The heat-resistant polyimide is obtained from: a tetracarboxylic acid component containing 75 mol% or more of 3,3',4,4'-biphenyltetracarboxylic acid dianhydride (s-BPDA) and 25 mol% or less of pyromellitic acid dianhydride (PMDA); and a diamine component containing 70-95 mol% of p-phenylenediamine and 5-30 mol% of 2,2'-dimethylbenzidine. The heat-bondable polyimide is obtained from: a tetracarboxylic acid component containing 10-60 mol% of the s-BPDA and 40-90 mol% of the PMDA; and a diamine component containing 50 mol% or more of 2,2-bis[4-(4-aminophenoxy)phenyl]propane.

The application discloses a kind of multilayer polyimide film and its preparation method and application, belong to high-performance polyimide technical field, solve the problem that PI film in prior art is not ideal when being applied to flexible PI board Heat stability.The method comprises: ODA, GAPD and DMAc are mixed under ice bath, after mixing BPDA and TAHQ, it is added in batches, to obtain solution B;SiO2 Aerogel is added to anhydrous ethanol, ultrasonic is obtained at room temperature, to obtain solution C;Solution B is coated into thin film, after drying, solution C is coated on it, after drying, solution B is coated on it again, drying is obtained Polyimide film.The multilayer low-dielectric polyimide film prepared by the application has the advantages of low dielectric, high temperature resistance, high interfacial compatibility and low water absorption.

This invention provides a multilayer polyimide film with excellent heat resistance, low dielectric loss tangent, and dimensional stability. The multilayer polyimide film comprises a heat-resistant polyimide layer and a heat-fusion polyimide layer laminated on one or both sides; the heat-resistant polyimide is obtained from a tetracarboxylic acid component containing more than 75 mol% of 3,3',4,4'-biphenyltetracarboxylic dianhydride (s-BPDA) and less than 25 mol% of pyromellitic dianhydride (PMDA), and a diamine component containing 70 mol% to 95 mol% of p-phenylenediamine and 5 mol% to 30 mol% of 2,2'-dimethylbenzidine; the heat-fusion polyimide is obtained from a tetracarboxylic acid component containing 10 mol% to 60 mol% of s-BPDA and 40 mol% to 90 mol% of PMDA, and a diamine component containing more than 50 mol% of 2,2-bis[4-(4-aminophenoxy)phenyl]propane.

The invention discloses a preparation method of an aluminum foil PI composite film with a high-density structure and the composite film prepared by the method. The composite film comprises three layers of structures: an upper layer is a thermosetting rigid polyimide composite film, a middle layer is an aluminum layer, and a lower layer is a thermoplastic flexible polyimide adhesive film; the upper layer is prepared from the following raw materials: 4, 4 '-diaminodiphenyl methane (PDA), 3, 3', 4, 4 '-biphenyl tetracarboxylic dianhydride (BPDA), graphene and silicon dioxide; the middle layer is an aluminum layer through vacuum sputtering and electroplating; the lower layer comprises the following raw materials: 3, 3 '-diaminodiphenyl sulfone (3, 3'-DDS), 1, 3-bis (4-aminophenoxy) benzene (1, 3, 4-APB) and 4, 4 '-oxydiphthalic anhydride (ODPA); the cable has the effects that the cable has excellent EMI shielding performance and good mechanical performance; the rigidity and stiffness of the film are effectively improved, the bonding effect is good, and hot-pressing bonding can be directly carried out.

The application discloses a high-strength plasticization-resistant gas separation membrane, a preparation method and application. By introducing a rigid group BPDA (3,3',4,4'-biphenyl tetracarboxylic dianhydride) with good crystallinity, PMDA (1,2,4,5-benzene tetracarboxylic dianhydride) and a high-crystallinity aromatic diamine into a 6FDA (hexafluoro dianhydride) and DABA (3,5-diamino benzoic acid) system, the flowability of a polymer chain is reduced, and the plasticization resistance and mechanical strength of the polymer are improved. In order to improve the solubility of monomers, a polyimide represented by a general formula (I) is obtained by dissolving a polymerization system by using a phenol as a solvent. The hollow fiber membrane prepared by spinning the obtained polyimide has the advantages of high strength, plasticization resistance and the like in a gas separation process, has good thermal stability, improves the permeation rate, and can maintain good selectivity for CO2 / N2 and CO2 / CH4, and has an important role in the field of flue gas and biogas CO2 removal. n is the polymerization degree of different components of the polymer, n is an integer of 100-200, and x is the mole ratio of the DABA part, x is an integer of 0-100.

The invention relates to the technical field of polyimide resin, in particular to modified polyimide resin for a glass fiber composite material as well as a preparation method and application of the modified polyimide resin. The preparation raw materials comprise a dianhydride monomer, a diamine monomer, an end-capping reagent, a filler and a solvent. The binary anhydride monomer comprises BPDA and ODPA; the diamine monomer comprises TFDB and TPE-R. The invention also discloses a preparation method of the diamine monomer. A quaternary copolymerization system constructed by binary anhydride monomers (BPDA and ODPA) and diamine monomers (TFDB and TPE-R) can improve the heat resistance and mechanical properties of the prepared resin; the weight ratio of BPDA to ODPA is 4: (0.5-2), and the weight ratio of TFDB to TPE-R is 1: (3-5), so that the toughness of the prepared resin can be further improved, and the elongation of the resin is greater than or equal to 25%.

The invention discloses a polyimide fiber as well as a preparation method and application thereof. The fiber adopts a'core layer-shell layer 'double high-heat-resistant cross-linked structure, a core layer and a shell layer both select a weak-bond-free high-rigidity heat-resistant monomer system, and the fiber is formed by copolymerization of a diamine system composed of p-phenylenediamine (PDA) and biphenyl diamine (BZ), a dianhydride system composed of benzene tetracarboxylic anhydride (PMDA) and 3, 3', 4, 4 '-biphenyl dianhydride (BPDA) and a dialkynyl-containing heat-resistant cross-linking agent. The glass transition temperature (Tg) of the fiber is greater than or equal to 320 DEG C, the 5% weight loss temperature (Td5) is greater than or equal to 580 DEG C under the condition that the temperature is increased by 10 DEG C / min in a nitrogen atmosphere, the tensile strength retention rate is greater than or equal to 70% after the fiber is exposed for 600 h in a 300 DEG C air environment, and the fiber has ultrahigh temperature resistance and structural stability and can be widely applied to the fields of aerospace high-temperature parts, electronic and electric power insulation, extreme environment protection and the like.

The present invention provides a low-dielectric polyimide film with excellent dimensional stability and heat resistance, comprising a block copolymer containing a first block and a second block. The first block is obtained by imidizing an acid dianhydride component containing biphenyl dianhydride (BPDA) with a diamine component containing p-phenylenediamine (PPD). The second block is obtained by imidizing an acid dianhydride component containing benzophenone tetracarboxylic dianhydride (BTDA) and pyromellitic dianhydride (PMDA) with a diamine component containing m-tolidine.

The application discloses black thermoplastic polyimide and a preparation method and application thereof, and relates to the technical field of polyimide. The application discloses thermoplastic polyimide with a new structure, and the structure of the thermoplastic polyimide is as follows, wherein diamine is ABABP and PNDA; and dianhydride is BPTME and BPDA. The application selects PNDA containing a chromophore group imido (-N-H-), and thus the thermoplastic polyimide with a black appearance is prepared without using black fillers.

The application discloses a preparation method of a five-element copolymer high-Tg polyimide film, which comprises the following steps: first, raw materials PDA, PMDA, M-TOLIDINE, ODA and S-BPDA are weighed according to proportions; PMDA is divided into three parts of dianhydride monomer A, dianhydride monomer B and dianhydride monomer C; PDA is dissolved in an organic solvent to obtain a diamine monomer solution; the dianhydride monomer A is added into the diamine monomer solution to obtain a mixed solution through stirring and mixing reaction; then, the M-TOLIDINE is added into the mixed solution to perform stirring and mixing reaction, and then the dianhydride monomer C is added into the mixed solution to perform stirring and mixing reaction; then, the ODA is added into the mixed solution to perform stirring and mixing reaction, and then the dianhydride monomer B is added into the mixed solution to perform stirring and mixing reaction; finally, the S-BPDA is added into the mixed solution to adjust the viscosity, and then the PAA is obtained through stirring and mixing reaction under a cold water bath condition; the PAA is coated on a glass plate, and then high-Tg polyimide film is obtained through thermal imidization under temperature rising. The high-Tg polyimide film produced by the application has good heat resistance and high heat dimensional stability, and promotes the application of the polyimide film product in the field of flexible display substrates.

The application relates to a two-dimensional covalent organic framework material based on Fe doping and bipyridine ligands, a preparation method and application thereof, and belongs to the technical field of covalent organic framework materials. N,N,N',N'-tetra-(p-aminophenyl)-p-phenylenediamine (TAPD) and 2,2'-bipyridine-5,5'-diformyl (BPDA) are used as ligands to synthesize JLNU-305, and JLNU-305-Fe is obtained after reaction with ferrous sulfate heptahydrate, which has multiple active sites (Fe 2+ , Fe 3+ and pyridine N), and exhibits excellent catalytic performance in the activation of sodium persulfate (PDS) for the degradation of 2,4-dichlorophenol (2,4-DCP) under room temperature conditions. At room temperature, 10mg / L of 2,4-dichlorophenol can be removed at a removal rate of 100% by JLNU-305-Fe in only 8min, and the performance is far superior to that of inorganic or organic porous organic polymers, and the JLNU-305-Fe has good reusability.

The application discloses a kind of medical instrument surface super slippery anticorrosive anticoagulant hydrogel composite coating and its preparation method and application, with N-(3,4-dihydroxyphenethyl)-2-benzoyl benzamide (BPDA) as primer, and the surface hydrogel composite coating formed by grafting hydrophilic polymer on it.Hydrophilic monomer surface grafting polymerization is initiated by light after BPDA is deposited on the surface of substrate, and a layer of hydrogel coating is constructed on the surface of BPDA primer.The primer BPDA provides excellent corrosion resistance, effectively reduces the corrosion rate of metal substrate, and the benzophenone derivative with photo-reactivity on BPDA molecule can mediate the firm combination of hydrogel layer;After meeting water, stable and dense hydration layer is formed, with super lubrication characteristics, which can significantly inhibit the adhesion of protein and cell, and effectively prevent the formation of thrombus.Its excellent anticorrosion and anticoagulant properties are widely applicable to the anticoagulant anticorrosion surface modification of medical instruments and other fields.

The invention relates to the field of power semiconductor packaging materials, in particular to a high-voltage power device mixed insulating material, a preparation method and application, and the preparation method comprises the following steps: step 1, dissolving BN nanoparticles under ultrasonic treatment by taking N, N-dimethylacetamide as a solvent to obtain a mixed solvent; step 2, adding 4, 4 '-diaminodiphenyl ether into the mixed solvent in an ice-water bath under a nitrogen atmosphere; step 3, adding 3, 3 ', 4, 4'-biphenyltetracarboxylic dianhydride into the intermediate mixture, and stirring to obtain PAA / BN; and 4, carrying out vacuum heat treatment on the PAA / BN to obtain the PI / BN insulating material. According to the invention, PI synthesized by two materials of BPDA (3, 3 ', 4, 4'-biphenyl tetracarboxylic dianhydride) and ODA (4, 4 '-diaminodiphenyl ether) through a two-step method is used as an insulating material, c-BN / h-BN is added as a nano filler by using the PI as a substrate, so that the novel insulating material is obtained, DBC of the PI / c-BN insulating material with the filler content of 10% successfully passes 7kV and 10kV partial discharge tests, no partial discharge occurs, and the insulating material has good insulation performance. And the voltage withstanding grade of the power module insulating material is improved.