5578 results about "Polyimide" patented technology

The invention discloses an MEMS device architecture, which comprises a cap layer, a device layer and a substrate layer, the cap layer is bonded with the device layer, the bonded whole is bonded with the substrate layer, the cap layer is manufactured based on a first silicon substrate, the bottom of the cap layer is provided with a cavity structure, and the cap layer is internally provided with a high-deep groove structure. A silicon dioxide film is arranged on the groove wall of the high-deep groove structure, polycrystalline silicon is deposited and filled in the high-deep groove structure, and a silicon dioxide layer is arranged on the upper surface of the first silicon substrate; the device layer is manufactured based on an SOI wafer and comprises a first silicon structure layer composed of top layer silicon, a buried oxide layer and a second silicon structure layer composed of back substrate silicon. The substrate layer comprises a second silicon substrate, a bottom layer cavity is formed in the top face of the second silicon substrate, and exhaust holes are formed in the bottom face of the second silicon substrate. According to the method, deep groove etching, polycrystalline silicon groove filling and bonding technologies are combined, advanced materials such as the SOI wafer and the polyimide layer are utilized, and excellent signal isolation and flexibility of various MEMS IMU applications are achieved.

A household vacuum sealer contains: a base, a lid, and a hot-melt sealing element. The base includes a receiving chamber for accommodating a control circuit and a vacuum pump. The base also includes a vacuuming chamber and an accommodation chamber. The hot-melt sealing element includes a holder, a mica slice, a laminated heating layer, the insulated composite layer, and a protective cap. The insulated composite layer includes multiple insulated tape layers. The laminated heating layer includes a high-temperature resistance tapes made of polyimide, a metal resistance tape, two electrical connection films, and two alternating current (AC) electrodes. The mica slice is parallelly fixed on a top of the holder. The laminated heating layer includes the two electrical connections. Furthermore, the protective cap is covered on the insulated composite layer and includes a hollowly elongated zone.

The invention relates to a charge accumulation characteristic analysis method for a polyimide material, and the method comprises the steps: applying a multi-stress synergistic effect to the polyimide material based on the multi-stress state of the polyimide material in the electric field, temperature, mechanical stress and irradiation in a deep space environment; a dynamic charge migration model of the polyimide material under the multi-stress synergistic effect is constructed, and the charge accumulation characteristic of the polyimide material is analyzed. According to the invention, based on the multi-stress state of electric field, temperature, mechanical stress and irradiation of the polyimide material in a deep space environment, a multi-stress synergistic effect is applied to the polyimide material, so that the problem of distortion of traditional single-stress or pairwise combined stress measurement is solved; through a dynamic charge migration model, charge accumulation characteristics of the polyimide material under the action of an electric field, temperature, mechanical stress and irradiation are analyzed, and accurate prediction, regulation and control for researching the electrical performance of the polyimide material are realized.

The invention provides a high-strength, light and supercritical foaming fabric and a preparation method thereof, complete fibers used by the fabric comprise core layer fibers and a skin layer material, the outer side of the core layer fibers is uniformly coated with the skin layer material, and the skin layer material can be foamed; the core layer fiber is at least one of aramid fiber, polyarylate fiber, polyimide fiber, ultra-high molecular weight polyethylene fiber, polyester fiber and polyamide fiber; and the skin layer is made of thermoplastic elastomer resin. The preparation method comprises the following steps: uniformly coating the outer side of the core layer fiber with the skin layer material, and then carrying out supercritical foaming on the skin layer material. According to the invention, the contradictory technical requirements of the fabric for shoes on strength, light weight, comfort and the like are solved in a simple mode; the body strength of the fiber for the shoes can be kept, and the characteristics of light weight and air permeability of the foaming fabric are also achieved; the difficulty of direct foaming of the fabric / fiber for shoes is reduced, and the vamp fabric and the shoe article which are uniform in foaming, breathable, light in weight, high in strength and soft can be obtained.

A polyimide film production line, comprising a steel belt casting machine (A), a peeling transition unit (B), a transverse stretching machine (C), an inspection unit (D), an annealing unit (E) and a winding unit (F) which are sequentially arranged, wherein a drying oven (1) of the steel belt casting machine (A) comprises a frame (11), outer thermally-insulating structures (5) arranged on two sides of the frame (11), and an upper air duct assembly (193) and a lower air duct assembly (194) which are arranged on the frame (11); the frame (11) comprises a bottom thermally-insulating layer (111), a middle-lower heat thermally-insulating layer (112), a middle-upper thermally-insulating layer (113) and a top thermally-insulating layer (114) which are sequentially spaced apart from each other from bottom to top and are parallel to each other; and the transverse stretching machine (C) comprises a transverse pulling box body (7) and a conveying system, and inner tracks (85) located in the transverse pulling box body (7) and outer tracks (86) located outside the transverse pulling box body (7) are provided between a driving sprocket assembly (82) and a driven sprocket assembly (81) of the conveying system. The polyimide film production line effectively reduces the total heating space in the drying box (1) and in the transverse pulling box body (7), the structure is more compact, and the heat loss during heat transfer is reduced, such that the energy consumption can be reduced, and the production cost is reduced.

The invention provides a preparation technology of a three-dimensional camera shooting sonar sparse sensing array, and the method comprises the following steps: forming a patterned electrode on a PVDF or P (VDF-TrFE) piezoelectric film through vacuum adsorption and silk-screen printing according to sparse array element coordinates, and arranging a virtual transition array element at the periphery; performing laser etching on the edge contour and the exhaust hole of the piezoelectric film; designing a bonding positioning auxiliary tool, combining an ultrathin double-sided adhesive tape and a single-sided mask adhesive tape, and utilizing conductive silver paste to realize accurate electric connection between the array element and the PCB bonding pad; designing a polytetrafluoroethylene-metal flattening module, and laminating the array in a vacuum environment for curing and bonding; the matching layer is made of a low-impedance sound transmission material, glue filling and vacuum defoaming are performed from the back side in batches, and the sparse sensing array is prepared in combination with a polyimide film and a metal super-flat plate. The preparation problem of the large-aperture high-frequency imaging sonar on the sensing array is solved, and the array element position accuracy, the array element consistency and the imaging resolution can be improved.

The invention belongs to the technical field of composite material design, and discloses a polyimide-based composite material design method and system based on experiment-machine learning collaborative optimization. The method comprises the following steps: S1, experimental database construction and machine learning performance modeling; S2, machine learning model construction and training; S3, model evaluation and performance index output; and S4, intelligent design of the polyimide-based composite material. The multi-objective performance collaborative optimization design and preparation of the polyimide-based ternary carbon heterostructure composite material are carried out by taking experimental data as a main material and machine learning as an auxiliary material. According to the method, an experiment-model-optimization closed-loop iterative design system is constructed based on an experiment-machine learning collaborative optimization method, the method has the advantages of high prediction precision, high optimization efficiency, good multi-target adaptability and the like, the development efficiency of the polyimide-based composite material is remarkably improved, and the development cost of the polyimide-based composite material is reduced. The method is suitable for intelligent design and large-scale application and popularization of the high-performance heat-conducting electromagnetic shielding material.

The invention relates to the technical field of flexible pressure sensors, in particular to a preparation method and application of a capacitance flexible pressure sensor with an adjustable gradient random micro-cone structure, and the sensor comprises an upper electrode and a lower electrode which are transparent indium tin oxide conductive films (PET / ITO); the packaging layer is a polyimide (PI) adhesive tape and covers the outer side of the electrode; the flexible isolation layer is polydimethylsiloxane (PDMS) with a hollow structure, and is positioned between the upper electrode and the lower electrode; the dielectric layer of a gradient random micro-cone structure is located in the flexible isolation layer and is formed by compounding polyvinyl alcohol (PVA) and phosphoric acid (H3PO4) according to the mass ratio of 1: 1; the gradient micro-cone structure and the ionization effect are combined, the electric double layer effect grading phenomenon occurs, and the gradient micro-cone sensor has the advantages of being high in sensitivity, wide in detection range, capable of keeping linearity under large pressure, short in response time and good in cycling stability.

The invention discloses a lithium ion battery composite diaphragm, a preparation method and a lithium ion battery, and relates to the technical field of lithium ion batteries. The lithium ion battery composite diaphragm comprises a base membrane and a functional coating arranged on the negative electrode side of the base membrane, the functional coating sequentially comprises an ion conducting layer, a thermal barrier layer and a self-repairing layer from the position close to the base film to the position far away from the base film; wherein the base membrane is a polyimide and aramid nanofiber blended electrostatic spinning membrane; the ion conducting layer comprises a compound of a modified fast ion conductor and polyvinylidene fluoride-hexafluoropropylene; the thermal barrier layer comprises a cross-linked network of boron nitride nanosheets and polybenzimidazole; the self-repairing layer comprises polyurethane microspheres loaded with dynamic disulfide bonds. The composite diaphragm provided by the invention can remarkably inhibit a purple area on the surface of a negative electrode, and enhance high-temperature self-protection and interface self-repairing of the lithium ion battery, so that the cycle and safety performance of the lithium ion battery are remarkably improved.

The invention relates to the technical field of drilling fluid cooling, and discloses a phase change microcapsule suitable for drilling fluid cooling and a preparation method thereof.The phase change microcapsule comprises a capsule wall stabilizing material and a capsule core phase change material, and the capsule wall stabilizing material comprises polyurethane, polyurea, polyamide, polyimide, polystyrene and a first organic solvent; the capsule core phase change material comprises paraffin, fatty acid, polyol, inorganic hydrated salt, polymer gel, expanded graphite, carbon nanotubes, metal nanoparticles and a second organic solvent, and the first organic solvent is at least one of toluene, xylene, cyclohexanone and the like. The temperature of the drilling fluid is kept at a relatively low level, the cooling of the drilling fluid is realized, so that the drilling efficiency is improved, harmful solvents and additives are not used in the preparation process of the phase-change microcapsules, the phase-change microcapsules are pollution-free to the environment, and the requirements of greenness and environmental protection are met.

The invention belongs to the technical field of protective coatings, and discloses an anti-corrosion, wear-resistant and high-temperature-resistant coating as well as a preparation method and application thereof. The coating comprises a primer, a middle transition layer and a finish; the raw materials of the primer comprise a primer material and a primer curing agent component; the primer material comprises modified epoxy phenolic resin, a primer functional filler, a first mixed solvent, a high-temperature-resistant coupling agent and an anti-settling agent; the raw materials of the middle transition layer comprise a middle transition layer material and a middle curing agent component; the materials of the middle transition layer comprise polyimide modified epoxy resin, a wear-resistant filler, a reactive diluent, a carbon nanotube, a first dispersant and a compatilizer; the raw materials of the finishing paint comprise a finishing paint material and a finishing paint curing agent component; the finishing paint material comprises organic silicon modified fluorocarbon resin, finishing paint functional filler, a second mixed solvent, a second dispersing agent and a flatting agent. According to the invention, a resin-based composite coating system is synergistically designed through multi-phase materials, so that optimal balance of corrosion resistance, wear resistance, toughness and high temperature resistance of the coating is realized.

The invention belongs to the technical field of high-temperature-resistant coatings, and particularly relates to a core-shell polyimide-based high-temperature-resistant water-based coating and a preparation method thereof. Comprising the following components in percentage by mass: 35-38% of a core-shell emulsion; the core layer is polyimide resin; the transition layer is an organic silicon emulsion modified by 5, 6-dimethyl benzimidazole and a silane coupling agent KH-550; the shell layer is made of polyamide-imide resin; 28%-32% of a modified high-temperature filler; 6%-7.5% of a functional auxiliary agent; and the balance of deionized water. Through core-shell emulsion gradient design, multi-scale filler cooperation and a low-temperature gradient curing process, the high temperature resistance, the adhesive force and the environmental protection property of the coating are improved.

The invention discloses a multi-layer protection cable resistant to an extreme environment, and belongs to the technical field of cables. The cable is of a seven-layer composite structure design and sequentially comprises a conductor, an insulating layer, a shielding layer, a buffer layer, a waterproof layer, a heat insulation layer and a protective outer layer from inside to outside, and the conductor is made of high-purity oxygen-free copper; the insulating layer is made of a polyimide material and has high temperature resistance, low temperature resistance and excellent insulating property; the shielding layer is composed of a tinned copper wire woven mesh and a high-permeability permalloy foil, and electromagnetic interference is effectively shielded; the buffer layer is made of an elastic rubber material to relieve mechanical stress; the waterproof layer adopts a nanoscale fluorosilicone resin coating and has excellent waterproof performance; the heat insulation layer is made of ceramic fibers and aerogel, and efficient heat insulation is provided; and the protective outer layer is made of a high-strength and corrosion-resistant polyether-ether-ketone (PEEK) material. The cable has excellent high temperature resistance, low temperature resistance, corrosion resistance and electromagnetic interference resistance, is suitable for extreme environments, and ensures stable transmission of electric power and signals under extreme conditions.

The invention relates to a building material, and particularly discloses a high-ductility cement-based composite material and a preparation method thereof.The cement-based composite material is prepared from, by weight, cement, water, an additive, PE fibers, modified PVA fibers, sand, hollow glass beads, silica fume, calcium silicate and expanded perlite; wherein the modified PVA fiber is prepared by compounding and modifying polyimide aerogel with acrylate resin and epoxy resin; the preparation method comprises the following steps: mixing the cement, the silica fume, the sand, the calcium silicate and the expanded perlite, and then adding the PE fibers to prepare a dry-mixed mixture; and mixing an additive with water to obtain a mixture, then adding the modified PVA fibers, uniformly stirring, then adding the dry-stirred mixture, and uniformly stirring to obtain the high-ductility cement-based composite material. According to the present invention, the fly ash is not added, such that the product quality stability is ensured, the good mechanical property and the good ductility are provided, and the energy saving and thermal insulation functions are provided.

The invention discloses a heat-insulating and high-temperature-resistant metal core fireproof plate and a preparation method thereof, belongs to the technical field of plate processing, and is used for solving the technical problem that the structural stability and fireproof performance of a fireproof plate in the prior art need to be further improved. The fireproof board comprises the two composite framework layers and the metal plate core layer arranged between the composite framework layers, in the process of preparing the fireproof board, aerogel and honeycomb polyimide resin are closely crosslinked through chemical bonds, in the supercritical drying process, the aerogel invades into gaps of a felt board to be solidified and closely combined with the felt board, and the fireproof board is formed. The aerogel layer serves as a heat insulation and sound insulation layer and is connected with all the layers at the same time, the honeycomb layer enhances the pressure resistance of the fireproof plate, all the layers are matched with one another in structure, and the fireproof plate which is flame-retardant, heat-insulation, bending-resistant, high-temperature-resistant, impact-resistant and stable is obtained.

The invention discloses a high-strength nano composite stiffening filling master batch and a preparation method thereof, and relates to the technical field of high polymer materials, the raw materials comprise a nano filler, a matrix material and a functional additive; the nano filler comprises nano diamond, nano silicon carbide and bio-based nano cellulose, the base material comprises polyimide, polyether-ether-ketone and bio-based polylactic acid, and the functional additive comprises a hindered phenol antioxidant, a nano aluminum hydroxide flame retardant, a nano silicon dioxide reinforcing agent, an ultraviolet light absorber, a carbon nano tube and nano silver particles. Nano-diamond, nano-silicon carbide and bio-based nano-cellulose are adopted as nano-fillers, polyimide, polyether-ether-ketone and bio-based polylactic acid are combined as base materials, and a plurality of functional additives are added, so that the preparation of the high-strength nano-composite stiffening filling master batch is realized; and the problems of poor dispersibility, mechanical property damage, insufficient hardness and poor interface bonding of the traditional filler master batch can be solved.

The invention relates to the technical field of insulating materials, in particular to insulating powder and a preparation method thereof. The invention discloses a flame-retardant coating which comprises the following components in parts by weight: 15-25 parts of epoxy resin, 10-20 parts of aluminum hydroxide, 5-12 parts of nano boron nitride, 1-3 parts of a silane coupling agent KH-560, 3-8 parts of polytetrafluoroethylene micro powder, 2-6 parts of fluorine-modified montmorillonite, 4-9 parts of melamine cyanurate, 2-5 parts of nano titanium dioxide, 1-4 parts of a fluorine-modified graphene oxide-polyaniline composite material and 0.5-2 parts of pentaerythritol stearate. The anti-corrosion coating is prepared from the following components in parts by weight: 1 to 3 parts of nano zinc oxide, 5 to 10 parts of glass fiber, 2 to 5 parts of polyhedral oligomeric silsesquioxane-polyimide copolymer, 1 to 4 parts of ferrocenyl epoxy resin and 0.5 to 2 parts of perfluorooctyltriethoxysilane. The insulation powder is high in corrosion resistance, excellent in insulation, heat dissipation and mechanical performance, environmentally friendly in processing, good in adaptability, capable of prolonging the service life of equipment and reducing the cost, suitable for special environments and wide in popularization prospect.

The invention relates to the technical field of magnetic materials, in particular to a ferrite neodymium iron boron composite magnetic material and a preparation method thereof. The ferrite neodymium iron boron composite magnetic material comprises the following raw materials in parts by weight: 20-30 parts of ferrite magnetic powder, 40-50 parts of neodymium iron boron magnetic powder, 5-10 parts of silicon dioxide, 2-5 parts of carbon nanotubes, 0.5-1 part of polyethylene and 0.5-2 parts of polyimide. The high-temperature-resistant and corrosion-resistant permanent magnet has high magnet performance and also has high-temperature-resistant performance and corrosion-resistant performance.

The invention relates to the technical field of dielectric materials, and discloses polyimide, a polyimide film and a preparation method and application thereof, the polyimide is obtained by a polymerization reaction of a dianhydride monomer and a diamine monomer, the diamine monomer comprises a methylene bridging group and a phenyl group with a substituent group, and the methylene bridging group is a phenyl group with a substituent group. The substituent group at least comprises one methyl group. The molecular twisted conformation lock structure provided by the invention not only can improve the tolerance of polyimide, but also can doubly inhibit intrachain and inter-chain charge migration of the dielectric film, so that the dielectric film still has extremely high energy storage density and energy storage efficiency at a service temperature close to a glass-transition temperature.

The utility model discloses a liquid crystal phased array based on a bidirectional switch. Comprising an upper quartz glass substrate, a lower quartz glass substrate, a liquid crystal medium arranged between the upper quartz glass substrate and the lower quartz glass substrate, polyimide films arranged above and below the liquid crystal medium, a Z-direction direct current bias network arranged on the upper surface of the lower quartz glass substrate, and a one-to-many power divider, the Y-direction direct current bias network is arranged on the lower surface of the lower quartz glass substrate, the metal ground is arranged on the lower surface of the upper quartz glass substrate, and the antenna units are coupled with the one-to-multiple power divider. Wherein the Z-direction direct-current bias network is controlled to apply a longitudinal electric field to the liquid crystal molecules, and the Y-direction direct-current bias network is controlled to apply a transverse electric field to the liquid crystal molecules. The utility model provides a liquid crystal phased array with quick response, which can obviously improve the performance index of a reconfigurable millimeter wave phased array system and is very beneficial to the integration and development of the reconfigurable millimeter wave system.

The invention discloses a shielding protection adhesive tape for semiconductor integrated circuit packaging and a preparation method thereof, and relates to the technical field of semiconductor integrated circuit packaging. The shielding protective adhesive tape for packaging the semiconductor integrated circuit is prepared by taking polyimide as a base material and coating a coating, and the coating comprises the following raw materials in parts by weight: 3-5 parts of modified nano silicon dioxide, 30-40 parts of N, N-dimethylformamide, 1-3 parts of a curing agent and 1-3 parts of a curing agent. The invention discloses a high-temperature-resistant epoxy resin coating which is prepared from the following components in parts by weight: 25-30 parts of N, N-dimethylformamide, 25-30 parts of a modified acrylate copolymer, 17-26 parts of ethyl acetate, 12-15 parts of epoxy resin, 1-2 parts of a silane coupling agent KH-550, 0.5-1 part of an antioxidant 1010, 0.3-0.8 part of an ultraviolet absorbent UV-327, 1-2 parts of carboxyl-terminated nitrile rubber, 2-4 parts of decabromodiphenyl ether, 0.1-0.3 part of an organic siloxane defoaming agent, 0.2-0.5 part of an acrylate flatting agent and 10-11 parts of diaminodiphenyl sulfone. The adhesive tape contains the modified nano silicon dioxide, the modified acrylate copolymer and other components, so that the performance of the adhesive tape is guaranteed; pretreatment is meticulous, preparation steps are standard, and mass production is easy; a finished product can be effectively shielded, and the packaging yield and the product stability can be improved.

The invention discloses a dry-process high-temperature-resistant lithium battery diaphragm and a preparation method thereof, and relates to the technical field of lithium battery diaphragms. The specific preparation method comprises the following steps: activating and cross-linking polypropylene, polyimide, a PP-b-PI block copolymer and a cross-linking agent BIBP under the protection of nitrogen to prepare a polypropylene-polyimide matrix; after melting, adding a pre-sintered ZrO2-coated Al2O3 core-shell filler, hydroxylated boron nitride and zinc borate, and carrying out double-stage screw extrusion, ultrasonic orientation, nitrogen annealing and cold roller quenching to obtain a mixed melt; carrying out warm stretching and hot air circulation heat treatment to prepare a hard elastic crystal base film; carrying out stretching, thermal relaxation and thermal shaping to obtain a microporous base membrane; after slitting, plasma activation is carried out, epoxy silane and tetraethyl orthosilicate / polybenzimidazole aerogel precursors are sprayed, and a nano closed-pore coating is formed through pre-curing and heat shrinkage curing; and finally eliminating static electricity and rolling to obtain a finished product. The lithium battery diaphragm prepared by the invention is excellent in high temperature resistance and low in thermal shrinkage rate.

The invention belongs to the technical field of chips, and discloses a vehicle gauge-level SMD chip crystal and a processing method thereof, and the method comprises the steps: forming a gradient doped region on the surface layer of a quartz wafer through an ion implantation technology, and carrying out the recognition of the surface defects of the wafer and the etching of an anchor point groove based on a visual detection system; the etched doped quartz wafer is subjected to micro-electro-mechanical processing, a double-cantilever supporting structure is formed, a three-dimensional electromagnetic shielding layer is constructed on the surface of the wafer subjected to cantilever processing, a ceramic substrate and a metal conducting layer are alternately deposited through an additive manufacturing process, a polyimide-silicon dioxide colloid material is provided, and the three-dimensional electromagnetic shielding layer is formed; gradient distribution of an adhesive layer is realized through a micro-droplet jetting technology, a polyimide-silicon dioxide composite stress buffer layer is coated on a ceramic substrate, alignment and patch packaging are carried out on a processed crystal and a substrate, and through material modification and process collaborative optimization, the method is suitable for application in a high-temperature environment; the reliability problem in the extreme environment of the vehicle gauge is solved, and meanwhile the yield is improved.

The invention provides a preparation method and application of a wear-resistant polyimide material, and the preparation method comprises the following steps: S1, adding a polyimide material into an alkali solution for reaction, cleaning reactants with acid and ethanol, and drying to obtain an activated polyimide material; s2, adding the activated polyimide material into a silane coupling agent solution for reaction, cleaning reactants with ethanol and water, and drying to obtain a modified polyimide material with silicon-oxygen bond active sites on the surface; s3, adding the modified polyimide material with silicon-oxygen bond active sites on the surface into a modified epoxy resin solution, adjusting the pH value to be acidic, and reacting to obtain the wear-resistant modified polyimide material, wherein the modified epoxy resin solution is obtained by reacting a silane coupling agent with acrylate. According to the method, the wear resistance of the polyimide can be improved on the premise that other properties of the polyimide material are not influenced.

The utility model discloses a bending-resistant radio frequency coaxial cable, which comprises an inner conductor, an insulating layer, a shielding layer and a sheath layer which are sequentially arranged from inside to outside, the inner conductor is formed by concentrically twisting a plurality of strands of silver-plated copper wire monofilaments; the insulating layer comprises an inner insulating layer and a polytetrafluoroethylene film outer insulating layer; the inner insulating layer is wrapped outside the inner conductor and is formed by sintering a polytetrafluoroethylene tape; the polytetrafluoroethylene film outer insulating layer is wrapped outside the inner insulating layer; the shielding layer comprises an inner shielding layer, a middle layer and an outer shielding layer, and the inner shielding layer is a silver-plated copper strip wrapping layer and wraps the insulating layer; the middle layer is a polyimide aluminum foil composite belt wrapping the inner shielding layer; the outer shielding layer is a silver-plated aramid yarn woven layer and is woven outside the middle layer; the sheath layer is a polytetrafluoroethylene sheath layer. The cable provided by the utility model has the characteristics of high-frequency bending resistance and good environment resistance, and also has excellent electrical transmission performance.

The invention discloses a preparation method of a high-temperature-resistant high-strength polyimide composite material, and relates to the technical field of polyimide composites.The preparation method comprises the following preparation steps that S1, a customized silane coupling agent is prepared; s2, preparing a bionic dynamic interface modified reinforcing filler, wherein the modified reinforcing filler is synergistically modified through a bionic coating and a customized silane coupling agent; and S3, preparing a polyimide precursor solution containing the dynamic network. According to the preparation method of the high-temperature-resistant high-strength polyimide composite material, through the integrated design of'customized silane coupling agent + bionic dynamic interface modification + dynamic network-containing polyimide precursor + gradient hot-pressing curing ', the glass-transition temperature of the prepared composite material is greater than or equal to 335 DEG C, the tensile strength is greater than or equal to 208 MPa, and meanwhile, the thermal repair efficiency at 180-250 DEG C is greater than or equal to 87%; the technical bottleneck that high temperature resistance, mechanical strength and repairing performance of the material are difficult to consider at the same time in the prior art is solved.

The invention discloses an insulating tape for a new energy battery and a preparation method of the insulating tape, and relates to the technical field of new energy battery assemblies. The insulating tape for the new energy battery is prepared by coating pretreated glass fiber cloth with a coating, the coating is prepared from the following raw materials in parts by weight: 15 to 20 parts of modified polyimide resin, 2 to 4 parts of epoxy resin E-51, 71 to 77 parts of an ethanol / butanone mixed solvent, 3 to 5 parts of modified nano silicon dioxide, 0.2 to 0.4 part of a silane coupling agent KH-550, 0.1 to 0.3 part of polydimethylsiloxane, 0.1 to 0.2 part of paraffin-based mineral oil and 0.3 to 0.5 part of triethylene tetramine. The glass fiber cloth pretreatment material comprises deionized water and a 5%-8% sodium hydroxide solution. The insulating adhesive tape for the new energy battery contains the modified polyimide resin, so that the high temperature resistance and electrolyte resistance of the adhesive tape can be enhanced, the insulativity is improved, and the modified nano silicon dioxide is good in dispersity. The preparation process is fine, the glass fiber cloth is fully pretreated, the preparation process is standard, and the use requirements of new energy batteries can be met.

The invention belongs to the field of advanced materials, and particularly relates to polyimide resin with low curing temperature and high heat resistance and a preparation method thereof. According to the invention, pararosaniline is introduced into the molecular chain structure of the phenylacetylene-terminated polyimide resin, and the curing temperature of the phenylacetylene-terminated polyimide resin is reduced by changing the spatial distortion degree of the polyimide molecular chain and introducing free radicals to catalyze the curing process. The polyimide resin can be cured and molded at a relatively low temperature, and keeps excellent heat resistance and mechanical properties. The forming temperature of the high-performance polyimide and the composite material thereof is effectively reduced, so that the manufacturing difficulty and cost are reduced, and the preparation method has important application prospects.

The present invention relates to a novel method for synthesizing olefin covalent organic framework foams, and polyimide, imine, hydrazone or Ketoenamine covalent organic frameworks (COFs). The method is a green synthetic strategy, including: under non-solvent condition, performing condensation reaction of a methyl-containing monomer and an aldehyde monomer with participation of acid anhydride or carboxylic acid compound to prepare olefin COFs; performing condensation reaction of a multihead acid anhydride or a multihead carboxylic acid monomer and an amino monomer with participation of acid anhydride or carboxylic acid compound to prepare amide COFs; and performing condensation reaction of the aldehyde monomer and the amino monomer with participation of acid anhydride, imidazole or carboxylic acid compound to prepare imine COFs. The COFs obtained by using the method have large specific surface area, regular and adjustable porous structure, and high crystallinity. The method effectively avoids use of organic solvent and risk of high pressure in the reaction process, and is suitable for large-scale preparation of COF materials.

To provide polyimide as an insulation material for preparing a printed circuit board.SOLUTION: Polyimide includes one or a plurality of repeating units derived from dianhydride, and one or a plurality of repeating units derived from diamine. Infrared absorption spectrum of the polyimide obtained through Fourier transform infrared spectroscopy (FTIR) using attenuated total reflection (ATR) has a characteristic peak A of 1,753 cm-1 to 1,803 cm-1, a characteristic peak B of 1,635 cm-1 to 1,752 cm-1, and a characteristic peak C of 1,160 cm-1 to 1,170 cm-1, the characteristic peak A has a characteristic peak area a, the characteristic peak B has a characteristic peak area b, the characteristic peak C has a characteristic peak area c, b / a is 25.00 or less, and c / b is 0.3000 or more.SELECTED DRAWING: None