86 results about "Thermoplastic polyimide" patented technology

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

The invention belongs to the technical field of high-performance polymer materials, and relates to thermal-crosslinkable polyimide, polyimide foam and a preparation method and application thereof. Aiming at the problem that the foaming performance of the existing polyimide foaming material is poor due to the fact that the melt strength and the chain segment activity are difficult to balance, the invention provides a method for regulating and controlling the rheological property by controlling the number-average molecular weight (Mn = 15-45kDa) of a precursor and introducing a thermally-crosslinkable end-capping group. The precursor can form a parison with a specific elastic network structure through hot-pressing cross-linking, and then the polyimide foam which is high in foaming rate, uniform and fine in foam hole, low in density and excellent in heat resistance can be prepared through a two-step method of supercritical fluid saturation pressure relief and high-temperature secondary foaming. The method realizes predictable control from molecular parameters to foaming performance, is suitable for various thermoplastic polyimide systems, and has a wide application prospect in the fields of aerospace heat insulation and the like.

This non-thermoplastic polyimide film (11) contains a non-thermoplastic polyimide. The non-thermoplastic polyimide includes a 3,3',4,4'-biphenyl-tetracarboxylic acid dianhydride residue, a 4,4'-oxydiphthalic acid anhydride residue, a p-phenylenediamine residue, and a 1,3-bis(4-aminophenoxy)benzene residue. The relationships A1 + A2 ≥ 80, B1 + B2 ≥ 80, and (A1 + B1) / (A2 + B2) ≤ 3.50 are satisfied, where A1 mol% is the 3,3',4,4'-biphenyl-tetracarboxylic acid dianhydride residue content, A2 mol% is the 4,4'-oxydiphthalic acid anhydride residue content, B1 mol% is the p-phenylenediamine residue content, and B2 mol% is the 1,3-bis(4-aminophenoxy)benzene residue content.

This invention discloses a high-modulus, high-toughness bismaleimide resin composition, a carbon fiber prepreg, and a preparation method thereof, belonging to the field of composite material technology. The bismaleimide resin composition of this invention comprises the following raw materials in parts by weight: 40-80 parts bismaleimide resin, 10-20 parts o-diallyl bisphenol A, and 5-10 parts a powder toughening agent containing phenolphthalein side chains. The carbon fiber prepreg of this invention is made from the above resin composition and carbon fibers, with thermoplastic polyimide felt interlayered to form an integrated structure. This allows the composite material prepared from the carbon fiber prepreg to maintain high modulus and high temperature resistance while significantly improving its toughness, impact damage tolerance, and interlayer delamination resistance. Furthermore, the prepreg of this invention has good processability and is suitable for manufacturing high-performance complex components.

The multilayer polyimide film (10) has a non-thermoplastic polyimide layer (11) and a thermoplastic polyimide layer (12) disposed on at least one surface of the non-thermoplastic polyimide layer (11). A non-thermoplastic polyimide contained in the non-thermoplastic polyimide layer (11) has, as a tetracarboxylic acid dianhydride residue, a tetracarboxylic acid dianhydride residue containing a benzophenone skeleton, and has, as a diamine residue, a diamine residue containing a biphenyl skeleton. Furthermore, in the multilayer polyimide film (10), the content of diamine residues containing a biphenyl skeleton in the non-thermoplastic polyimide is 30-100 mol% with respect to the total diamine residues constituting the non-thermoplastic polyimide.

The invention discloses a flexible copper-clad plate with high thermal conductivity and low dielectric property and a preparation method of the flexible copper-clad plate. The flexible copper-clad plate comprises an insulating substrate, the composite film is a thermoplastic polyimide / heat-conducting low-dielectric ePTFE / thermoplastic polyimide insulating composite film which is composed of a middle layer ceramic / boron nitride-expanded polytetrafluoroethylene functional hybrid membrane and thermoplastic polyimide layers on the two sides of the middle layer ceramic / boron nitride-expanded polytetrafluoroethylene functional hybrid membrane. And the flexible conductive metal foil is compounded with the single surface, double surfaces or multiple layers of the insulating substrate through a thermal forming compounding process. Through the mode, the flexible copper-clad plate can have excellent peel strength under the adhesive-free condition through structure optimization and process innovation, low dielectric constant and low dielectric loss tangent value can be realized under the high-frequency condition, and meanwhile, the heat conductivity coefficient is remarkably improved. And through continuous production, the efficiency is greatly improved, and a high-reliability base material is provided for the high-end electronic fields such as new energy vehicles, 5G / 6G communication and wearable equipment.

The present application relates to the field of polyimide film, provide a kind of thermoplastic polyimide film steel plate preparation method and device, including the following steps;Provide steel foil, and prepare polyamide acid solution;Coated with a layer of polyamide acid solution on the rough surface of steel foil;The steel foil coated with polyamide acid solution obtained is placed on the rack in the furnace body and baked, and the steel foil covered with polyamide acid film is obtained;The steel foil covered with polyamide acid film obtained is subjected to thermal imidization, and the polyimide film steel plate is obtained.By being provided with the rack of metal material in the furnace body, the rack divides the furnace body into two heating cavities, and the two heating cavities are communicated through gap, and the heating pipe in lower chamber is heated towards the polyamide acid film on one side of copper foil, and the other side of polyamide acid film is not placed heating pipe, so that the heat in lower heating cavity is conducted to upper chamber through gap, and the other side of polyamide acid film is heated, and the heating efficiency is improved.

An insulated wire and a preparation method therefor, a coil, and an electronic / electrical device are provided. In the preparation method, the thermoplastic polyimide is extruded to mold by adopting the extrusion process, so as to form the insulating layer on the core material, which can significantly improve the production efficiency compared to the traditional multiple-time coating process. The preparation process of the bonding layer and the extrusion process are optimized; the bonding layer is prepared by a specific bonding layer formulation; and then the insulating layer is extruded under a specific negative pressure, so that the prepared thermoplastic polyimide insulating layer has fewer bubbles, and the size of the bubbles is smaller, which ensures the insulating layer to have a higher breakdown voltage.

An insulated wire and a preparation method therefor, a coil, and an electronic / electrical device are provided. In the preparation method, the thermoplastic polyimide is extruded to mold by adopting the extrusion process, so as to form the insulating layer on the core material, which can significantly improve the production efficiency compared to the traditional multiple-time coating process. The preparation process of the bonding layer and the extrusion process are optimized; the bonding layer is prepared by a specific bonding layer formulation; and then the insulating layer is extruded under a specific negative pressure, so that the prepared thermoplastic polyimide insulating layer has fewer bubbles, and the size of the bubbles is smaller, which ensures the insulating layer to have a higher breakdown voltage.

The invention relates to a composition comprising: a poly(ether ketone ketone), PEKK1; a thermoplastic polyimide having a glass transition temperature greater than or equal to 230°C, TPI; and optionally, a poly(aryl ether ketone), PAEK, PAEK being distinct from PEKK1. PEKK1 represents at least 50% by weight, relative to the total weight of PEKK1, TPI and, where applicable, PAEK, of the composition. PAEK is necessarily present when the TPI content is greater than or equal to 20% by weight, and preferably when the TPI content is greater than or equal to 15% by weight, relative to the total weight of PEKK1 and TPI of the composition.

The present application provides an insulated wire and a preparation method therefor, a winding wire, and an electrical device, relating to the technical field of electrochemical elements. The insulated wire includes a conductor and an intermediate layer and an insulation layer sequentially coated on the conductor; the insulation layer includes thermoplastic polyimide and polyetheretherketone; a mass percentage of the thermoplastic polyimide in the insulation layer ranges from 85% to 95%, and a mass percentage of the polyether ether ketone in the insulation layer ranges from 5% to 15%; the number of bubbles with a pore size of 30 µm or more in the insulation layer is not more than 5 per 100 m. The present application further provides a preparation method for the above insulated wire, and a winding wire and an electrical device using the above insulated wire. The insulated wire provided in the present application overcomes the defect in the prior art that bubbles are easy to appear, when the thermoplastic polyimide is taken as the insulating layer, to cause a local breakdown voltage to be low.

The invention discloses a method for continuously synthesizing thermoplastic polyimide through polymerization-extrusion granulation, and relates to the technical field of high-performance polymer synthesis, and the method comprises the following specific steps: mixing dianhydride and diamine monomer according to a ratio, and reacting in a water-containing solvent or a pure water phase to obtain an oligomer mixture; carrying out flash evaporation under the negative pressure of-0.01 to-0.1 MPa to recover the solvent / water, so as to obtain polyimide oligomer powder; drying the powder, mixing the dried powder with an auxiliary agent and other flexibilizers, carrying out stepped heat treatment in a nitrogen atmosphere, conveying the mixture into a screw machine through a screw, extruding, and pelletizing to obtain thermoplastic polyimide particles; the continuous production of the thermoplastic polyimide is realized by integrating core procedures, and the material loss and the time cost are reduced; and auxiliary materials such as the antioxidant and the flexibilizer are added, so that the product performance is improved, the application range is widened, and efficient and low-carbon production is realized.

The utility model relates to the technical field of film heaters, in particular to an irradiation-resistant heater, which comprises an electric heating layer, a pair of leads and a pair of insulating layers. The electric heating layer is fixedly arranged between the pair of insulating layers; the head ends of the pair of wires are electrically connected with the positive electrode of the electric heating layer and the negative electrode of the electric heating layer respectively. According to the utility model, the thermoplastic connecting layer made of the thermoplastic polyimide material is adopted to replace a bonding layer of a film heater in the prior art, so that the total radiation-resistant dose of the device is improved to 1.0 * 1010rad (SI), and the device can meet the requirements of the use environment outside a spacecraft cabin; the defect that a film heater in the prior art is poor in environment adaptability is overcome.

The application provides a high thermal and oxidative stability polyimide composite film and a preparation method thereof.The high thermal and oxidative stability polyimide composite film comprises a non-thermoplastic polyimide layer and a first thermoplastic polyimide layer, and the first thermoplastic polyimide layer is located on the first side of the non-thermoplastic polyimide layer; the non-thermoplastic polyimide layer and the first thermoplastic polyimide layer both contain rare earth oxides; and the first thermoplastic polyimide layer contains a toughening agent with a -COOH, -N-H or -C=O polar group.The film is modified by the toughening agent, the bonding strength is improved, the overall thermal and oxidative stability of the film is improved by the rare earth oxides, and the adverse influence of the toughening agent on the mechanical properties of the resin is reduced as much as possible, so that the thermal and oxidative stability of the film is improved as a whole.

The present application relates to the technical field of 5G high-frequency copper-clad plate, and particularly relates to polyimide, a preparation method thereof, a composition and a polyimide film. The polyimide is shown as formula 1, wherein n is an integer of 10-100; A is selected from one or more of substituted or unsubstituted aromatic hydrocarbon groups, saturated or unsaturated aliphatic groups; R1 is selected from substituted or unsubstituted saturated aliphatic hydrocarbon groups; and R is selected from one or more of substituted or unsubstituted aromatic hydrocarbon groups, saturated or unsaturated aliphatic groups. The present application adopts an anhydride containing a terminal carboxyl structure, seals the polyimide to form an oligomer prepolymer containing a carboxyl group, and then introduces a fatty alcohol containing a terminal hydroxyl group to form an ester group structure, so as to obtain a polyester polyimide. The material has a lower dielectric constant and higher adhesion. The polyimide is applied to thermoplastic polyimide (TPI), and the pressure bonding temperature is lower.

The application provides a thermoplastic polyimide prepreg preparation method and a special device thereof, and preparation includes unwinding, cloth storage and desizing, one-time impregnation, secondary impregnation, pre-drying, three-time impregnation and drying and the like. The application adopts three-time impregnation process and special one-time impregnation device and drying device, realizes solvent method preparation of high-performance thermoplastic prepreg, and solves the problems of low resin content, insufficient impregnation, insufficient flatness of the prepreg, and defects such as air holes and pitting. The method has high preparation efficiency and less wear, the prepared prepreg has uniform fiber impregnation, smooth surface, uniform thickness, high strength and impact resistance, can be stored for a long time and recycled, and is suitable for manufacturing of resin prepreg with high melt viscosity and soluble in proper single or mixed solvent. The prepared prepreg can be applied to the manufacturing of lightweight high-performance parts in the fields of rail transportation, aerospace, weapons and the like.

A method for manufacturing an electrically conductive member, which includes: attaching a powder to a surface of a metal member by an electrostatic coating method, the powder containing a thermoplastic polyimide containing a structural unit represented by formula (1); and forming an insulating coating film by melting the attached powder by heating, in an IR spectrum of the insulating coating film, at least one of the following conditions is satisfied: a ratio I ‑1 / I 1487 of an absorption intensity I ‑1 at 1487 cm 1778 to an absorption intensity I 1487 at 1778 cm 1778 is 3.0 to 5.0; and a ratio I ‑1 / I 1232 of an absorption intensity I ‑1 at 1232 cm 1778 to an absorption intensity I 1232 at 1778 cm 1778 is 3.0 to 5.0.

A multi-layered polyimide film includes a non-thermoplastic polyimide layer and at least one thermoplastic polyimide layer disposed on at least one surface of the non-thermoplastic polyimide layer. A non-thermoplastic polyimide contained in the non-thermoplastic polyimide layer has a tetracarboxylic dianhydride residue including a benzophenone skeleton, as a tetracarboxylic dianhydride residue, and has a diamine residue including a biphenyl skeleton, as a diamine residue. In the multi-layered polyimide film, the content rate of the diamine residue including a biphenyl skeleton in the non-thermoplastic polyimide is 30 mol % or more and 100 mol % or less with respect to all of diamine residues included in the non-thermoplastic polyimide.

The present application provides an insulated wire and a preparation method therefor, a winding wire and an electrical device, relating to the technical field of electrochemical elements. The insulated wire includes a conductive wire and an insulating layer coated on the conductive wire, where the insulating layer includes polyetheretherketone and thermoplastic polyimide, and a mass percentage of the polyetheretherketone in the insulating layer is not more than 20%; and the conductive wire is in direct contact with the insulating layer; and after extrusion and cooling for 24 h, under a condition that the insulated wire is ring cut and stretched by 15%, a length of the insulating layer losing adhesion is not greater than 1.9 mm. The present application further provides a preparation method for the above insulated wire and an electrical device using the above insulated wire. The insulated wire provided in the present application overcomes the defect of poor adhesive force between the insulating layer and the conductive wire in the prior art.

The preparation method comprises the following steps: dissolving a diamine monomer in a polar solvent, then adding an end-capping reagent and a dianhydride monomer, and carrying out a stirring reaction so as to obtain a polyamide acid solution; then sequentially adding a poor solvent, a dehydrating agent and a catalyst, and stirring to complete imidization; and carrying out suction filtration and washing for multiple times, and finally drying to obtain the polyimide granules capable of being subjected to injection molding. The prepared polyimide has high Tg, the melting temperature ranges from 320 DEG C to 340 DEG C, the heat resistance and the machinability of a product are considered, in addition, the melt index is moderate, direct injection molding can be achieved without granulation, the mechanical property of an injection molded part is good, and the thermoplastic polyimide is the thermoplastic polyimide which has the heat resistance and the machinability and is excellent in comprehensive performance and used for direct injection molding machining forming.

The present application relates to the technical field of high-performance resin film, and particularly relates to a polyimide modified thermotropic liquid crystal resin composition and double-sided copper clad plate. The composition comprises a polyimide resin and a thermotropic liquid crystal resin, wherein the polyimide resin comprises a structure shown in formula (1) and each group in formula (1) has a specific selection. The present application significantly improves the cohesion and orientation of the resin from the chemical structure and condensed state structure by using a thermoplastic polyimide resin with a specific structure to blend and modify the thermotropic liquid crystal resin. The double-sided copper clad plate prepared therefrom has high peeling strength and excellent isotropy, and has a good application prospect in the field of high-frequency flexible microwave circuit and the like. Formula (1).

The invention provides soluble thermoplastic polyimide resin and a preparation method thereof, a coating, a composite film and a flexible copper-clad plate. According to the invention, large-volume functional groups are concentrated in an X chain segment and enter a molecular main chain in the form of a block structure, so that the distance between molecular chains can be further increased, solvent molecules enter wound molecular chain groups, and the effect of increasing the solubility is achieved. Moreover, while the solubility is enhanced, the proportion of large-volume functional group monomers can be reduced by the block structure, and the influence of the large-volume functional group monomers on the flexibility of a molecular main chain is reduced. Therefore, the polyimide resin provided by the invention still has a relatively low glass transition temperature.

This invention provides a multilayer film, a metal-clad laminate, and a circuit board. The multilayer film has outer layers comprising multiple polyimide layers on both sides of an inner layer including an adhesive layer, ensuring dimensional stability while further improving dielectric properties. The multilayer film includes multiple polyimide layers and an adhesive layer, wherein the multilayer film satisfies: a) the total thickness of the thermoplastic polyimide layer and the non-thermoplastic polyimide layer stacked on one side of the adhesive layer is in the range of 2 μm or more and 20 μm or less; b) 65 < P P / P AD <1,550, by P P =P P1 +P P2 P P1 =(E' P100 +E' P200 )×thickness of polyimide layer [μm], P P2 =(E' P100 +E' P200 )×thickness of polyimide layer [μm], P AD =(E' AD100 +E' AD200 E' represents the thickness of the adhesive layer [μm]. P100 、E' P200 E' is the storage elastic modulus [GPa] of the polyimide layer at 100℃ and 200℃. AD100 、E' AD200 c) The storage elastic coefficient [GPa] of the adhesive layer at 100℃ and 200℃; c) As a whole multilayer film, the dielectric loss tangent at 20 GHz measured using an SPDR resonator is less than 0.0029.

The invention provides a polyimide supercritical foaming material and application thereof, and relates to the technical field of foaming polyimide. The main chain structure of the thermoplastic polyimide contains a plurality of ester bonds, and the thermoplastic polyimide is prepared from the following raw materials: a dianhydride compound, a diamine compound and di-p-aminophenyl terephthalate, so that the affinity to CO2 is improved while the thermoplasticity of the polyimide is improved, and the thermoplastic polyimide has better foaming performance under CO2 supercritical foaming. The supercritical foaming material provided by the invention is suitable for wave-absorbing materials.

This invention relates to a fiber-reinforced thermoplastic polyimide laminate, its preparation method, and its application. The preparation method includes the following steps: S1: Prepare a diamine solution, add a dianhydride to the diamine solution to obtain a precursor solution, and prepare a diluent; S2: Add the diluent to the precursor solution to obtain an impregnation resin; S3: Coat the impregnation resin onto the surface of a substrate to form a wet film, and then perform a first drying treatment on the wet film to obtain an adhesive film; impregnate a fiber fabric with the impregnation resin or coat the surface of the fiber fabric with the impregnation resin to obtain an impregnated fabric, and then perform a second drying treatment on the impregnated fabric to obtain a prepreg; S4: Stack m prepreg sheets and n adhesive films alternately along the thickness direction to form a laminate, wherein m≥1, n≥1, and then hot-press the laminate to obtain a thermoplastic polyimide laminate. This invention has a simple process, high preparation efficiency, and the resulting laminate has excellent mechanical properties.

The application discloses a thermoplastic polyimide and application thereof in temporary bonding technology. A preparation method of the thermoplastic polyimide comprises the following steps: obtaining polyamide acid which is a polyimide precursor by copolymerization of a diamine and a dianhydride; and obtaining the thermoplastic polyimide by thermal imidization of the polyamide acid; wherein the temperature of the thermal imidization is 200 DEG C-350 DEG C, and the curing time of the thermal imidization is 0.5h-10h; the diamine is a diamine with flexible bonds and rigid groups; and the dianhydride is a dianhydride with flexible bonds and rigid groups. The thermoplastic polyimide provided by the application meets the process requirements of easy bonding and debonding in the process of ultra-thin wafer processing in the ultraviolet laser temporary bonding technology, improves the efficiency and safety of the temporary bonding process, and has potential application value in electronic packaging.

The application provides a polyimide composite film preparation method and a polyimide composite film. The polyimide composite film preparation method comprises the following steps: providing a first polyamic acid capable of forming a thermoplastic polyimide, wherein the first polyamic acid is terminated by a carbonylimidazole group; providing a second polyamic acid capable of forming a non-thermoplastic polyimide, wherein the second polyamic acid is terminated by an anhydride group; co-extruding and cyclizing the first polyamic acid and the second polyamic acid to obtain a polyimide composite film, wherein the polyimide composite film has amide groups generated by the reaction between the carbonylimidazole group and carboxyl groups in the second polyamic acid.

The application provides a soluble thermoplastic polyimide resin, a preparation method thereof, a coating, a composite film and a flexible copper-clad plate. The application concentrates bulky functional groups in X segments and enters the molecular main chain in a block structure, so that the molecular chain spacing is further increased, the solvent molecules enter the inside of the entangled molecular chain group, and the solubility is increased. Moreover, while the solubility is increased, the block structure can reduce the proportion of the bulky functional group monomers and reduce the influence of the bulky functional group monomers on the flexibility of the molecular main chain. Thus, the polyimide resin of the application still has a low glass transition temperature.

The application discloses an epoxy resin surface alternate spraying embedded type composite coating and a preparation method, belongs to the technical field of composite coating, and mixes thermoplastic polyimide powder, thermosetting polyimide powder, nano alumina powder, deionized water and a binder, sprays and granulates after ball milling to obtain polyimide-nano Al2O3 composite powder; and the polyimide-nano Al2O3 composite powder and Al2O3 powder are alternately sprayed on a resin-based composite material. In the application, the polyimide-nano Al2O3 composite material is introduced as a transition layer, the high combination of the glass fiber reinforced resin-based composite material and the alumina ceramic layer is ensured, and the temperature resistance and wear resistance of the matrix are improved. The alumina is in an embedded structure in the polymer-based nano composite coating, the highest bonding strength reaches 20 MPa, and the highest resistivity reaches 71 TΩ.cm. Compared with a pure matrix, the bending strength is 235 MPa after ablation for 150 times, is increased by 28%, and excellent plasma ablation resistance is shown.

The present application relates to an electrically insulating laminate for electrical machine applications comprising a flexible polymer layer having a first thermoplastic polyimide having a glass transition temperature (Tg) in the range of 140 DEG C to 280 DEG C, and a first flexible cushion layer having a first organic material having a second thermoplastic polyimide having a glass transition temperature (Tg) in the range of 140 DEG C to 280 DEG C, the first organic material includes a woven, non-woven, or fiber, and the flexible polymer layer is thermally bonded and in direct contact with the first organic material. The electric machine includes the electrically insulating laminate.