A bending-resistant and high-thermal-conductivity aluminum-based copper-clad laminate and its preparation method

Abstract

The present invention discloses a bend-resistant, high-thermal-conductivity aluminum-based copper-clad laminate and a preparation method thereof, relating to the technical field of aluminum-based copper-clad laminates. In the preparation of the bend-resistant, high-thermal-conductivity aluminum-based copper-clad laminate, the present invention comprises reacting 2,7-dinitro-9-fluorenone with resorcinol, converting the nitro group into an amino group to produce a modified monomer; polymerizing a polyimide monomer and then reacting it with 1-aminomethylmaleimide hydrochloride to produce a modified polyimide; nitriding an aluminum sheet and then reacting it sequentially with allyltrimethoxysilane, 4-(aminomethyl)-2-(tert-butyl)phenol, and furan, 2-(2-chloroethyl) to produce a functionalized aluminum sheet; thermally polymerizing the modified polyimide and then mixing it with bisphenol A epoxy resin and acetone; bonding a rolled copper foil to the functionalized aluminum sheet, and hot pressing to produce the bend-resistant, high-thermal-conductivity aluminum-based copper-clad laminate. The bending-resistant and high-thermal-conductivity aluminum-based copper-clad plate prepared by the present invention has the effects of waterproofing, self-repairing, durability and high-temperature resistance of the insulation layer.

Description

Technical Field

[0001] The present invention relates to the technical field of aluminum-based copper-clad laminates, and in particular to a bending-resistant and high-heat-conductivity aluminum-based copper-clad laminate and a preparation method thereof. Background Art

[0002] Aluminum-based copper-clad laminate, also known as aluminum substrate, is a plate-like material made of electronic fiberglass cloth or other reinforcing materials impregnated with resin, single resin, etc. as an insulating adhesive layer, covered with copper foil on one or both sides and hot-pressed. It is called copper-clad aluminum laminate, abbreviated as aluminum-based copper-clad laminate. As a substrate material in the manufacture of printed circuit boards, it mainly plays the role of interconnection, conduction, insulation and support for printed circuit boards, and has a great influence on the transmission speed, energy loss and characteristic impedance of signals in the circuit. The performance, quality, processability, manufacturing level, manufacturing cost, long-term reliability and stability of printed circuit boards depend to a large extent on the aluminum-based copper-clad laminate.

[0003] Aluminum-based copper clad laminates are widely used in the electronics industry, especially in situations where good heat dissipation performance is required. Aluminum-based copper clad laminates are widely used in LED lighting products, power electronic equipment, computers, automotive electronics and other fields. In these applications, aluminum-based copper clad laminates often need to be bent to adapt to complex circuit designs and component layouts, so their bending resistance is crucial. Aluminum-based copper clad laminates will transfer heat from heating elements to the aluminum base layer. If the thermal conductivity is poor, it will cause local high temperatures, accelerate component aging or even burn out, and form a huge temperature difference between local high and low temperature areas, generating thermal stress, causing copper foil circuit cracking or insulation layer delamination. Therefore, this application introduces a bending-resistant and high-thermal-conductivity aluminum-based copper clad laminate and its preparation method. Summary of the Invention

[0004] The object of the present invention is to provide a bending-resistant and high-thermal-conductivity aluminum-based copper-clad laminate and a preparation method thereof, so as to solve the problems existing in the prior art.

[0005] A bend-resistant, high-thermal-conductivity aluminum-based copper-clad laminate, which is prepared by thermally polymerizing a modified polyimide, mixing it with a bisphenol A epoxy resin and acetone, bonding a rolled copper foil and a functionalized aluminum sheet, and hot pressing.

[0006] The functionalized aluminum sheet is prepared by sequentially reacting the aluminum sheet with allyltrimethoxysilane, 4-(aminomethyl)-2-(tert-butyl)phenol and furan, 2-(2-chloroethyl) after nitriding treatment.

[0007] The modified polyimide is prepared by polymerizing polyimide monomer and then reacting it with 1-aminomethylmaleimide hydrochloride;

[0008] The polyimide monomers are respectively a modified monomer, diphenyl hexafluoroisopropyl tetracarboxylic dianhydride, 3,3′,4,4′-dibenzophenone tetracarboxylic dianhydride and 4-aminobenzonitrile;

[0009] The modified monomer is prepared by first reacting 2,7-dinitro-9-fluorenone with resorcinol and then converting the nitro group into an amino group.

[0010] A method for preparing a bending-resistant and high-thermal-conductivity aluminum-based copper-clad laminate, the method mainly comprising the following preparation steps:

[0011] (1) Pre-modified polyimide, 1-aminomethylmaleimide hydrochloride and toluene were mixed in a mass ratio of 4-6:20-30:1, stirred at 150-170°C and 200-300 r / min for 22-26 h, cooled to room temperature, filtered, washed with deionized water 3-5 times, and vacuum dried at 55-65°C for 11-13 h to obtain modified polyimide;

[0012] (2) Furan, 2-(2-chloroethyl), dimethyl sulfoxide and modified aluminum sheet were mixed in a mass ratio of 1:8~12:3~5, ultrasonicated at 85~95℃ for 11~13h, taken out, washed with deionized water 3~5 times, and dried at 40~50℃ for 11~13h to obtain functionalized aluminum sheet;

[0013] (3) The modified polyimide and bisphenol A epoxy resin were mixed evenly in a mass ratio of 1:4~6, and coated on the surface of the polypropylene film with a thickness of 48~52μm. The film was dried at 80~90℃ for 4.5~5.5min, cooled to room temperature, and a 0.6mm thick rolled copper foil was pasted on the surface. The film was laminated at 115~125℃ for 3~5min. The polypropylene film was peeled off and a functionalized aluminum sheet was pasted on the surface. The film was placed in a hot press with a pressure of 0.16MPa, heated to 170~180℃, kept warm for 80~100min, and naturally cooled to room temperature to obtain an aluminum-based copper clad laminate.

[0014] As an optimization, the pre-modified polyimide in step (1) is prepared by mixing the modified monomer, diphenylhexafluoroisopropyl tetracarboxylic dianhydride, 3,3′,4,4′-dibenzophenone tetracarboxylic dianhydride, N-methylpyrrolidone and isoquinoline in a molar ratio of 8-10:6-7:3-4:30-40:0.01, stirring at 200-300 r / min for 50-70 min, heating to 175-185°C at 40°C / h, stirring for 46-50 h, cooling to room temperature, adding 4-aminobenzonitrile in an amount of 0.38-0.42 times the molar amount of the modified monomer, continuing stirring for 50-70 min, heating to 175-185°C at 40°C / h, stirring for 22-26 h, cooling to room temperature, pouring into ethanol, filtering, washing with ethanol 3-5 times, and vacuum drying at 55-65°C for 5-7 h.

[0015] As an optimization, the modified monomer is prepared by uniformly mixing ethanol and water in a volume ratio of 2.8~3.2:1 to obtain an ethanol aqueous solution; uniformly mixing the pre-modified monomer, 200-mesh zinc powder, and ammonium chloride in a molar ratio of 1:11~13:3.5~4.5, adding ethanol aqueous solution 12~13 times the mass of the pre-modified monomer and glacial acetic acid 4.2~4.6 times the molar amount of the pre-modified monomer, at 200~300 r / min, 58~62°C, under argon protection, stirring for 6~7 hours, filtering, washing with deionized water 3~5 times, and vacuum drying at -10~0°C for 22~26 hours to obtain the modified monomer.

[0016] As an optimization, the pre-modified monomer is prepared by mixing 2,7-dinitro-9-fluorenone and resorcinol in a molar ratio of 1:2.4~2.6, adding p-toluenesulfonic acid in an amount 1.4~1.6 times the molar amount of 2,7-dinitro-9-fluorenone under argon protection, stirring at 200~300 r / min and 135~145°C for 5~7 hours, cooling to room temperature, adding methanol in an amount 4~5 times the molar amount of 2,7-dinitro-9-fluorenone, stirring at 200~300 r / min for 8~10 minutes, pouring into deionized water, standing for 20~30 minutes, filtering, washing with deionized water 3~5 times, and vacuum drying at -10~0°C for 22~26 hours.

[0017] As an optimization, the modified aluminum sheet in step (2) is prepared by mixing the pre-modified aluminum sheet, ethanol and 4-(aminomethyl)-2-(tert-butyl)phenol in a mass ratio of 1:4~6:0.28~0.32, ultrasonically treating at 45~55°C under argon protection for 1.5~2.5h, taking out, washing with deionized water 3~5 times, and drying at 40~50°C for 11~13h.

[0018] As an optimization, the pre-modified aluminum sheet is prepared by evenly applying the surface treatment liquid on the aluminum sheet containing an aluminum nitride layer on the surface, standing it at 85~95°C for 5~7 hours, repeating the application and drying 5 times, washing it with deionized water 6~8 times, and drying it at 40~50°C for 22~24 hours.

[0019] As an optimization, the surface treatment liquid is prepared by mixing allyltrimethoxysilane and isopropyl alcohol in a mass ratio of 1:8-12, and adjusting the pH to 4-6 with a 0.1 mol / L acetic acid aqueous solution.

[0020] As an optimization, the aluminum sheet containing an aluminum nitride layer on the surface is prepared by grinding a 1 mm thick aluminum sheet to 0.8 mm using silicon carbide sandpaper of models P1000, P1500, and P2000, polishing it with W1 diamond polishing agent, ultrasonicating it in ethanol for 8 to 12 minutes, vacuum drying it at 50 to 60°C for 6 to 8 hours, and placing it in a fully automatic pulse power ion nitriding furnace. The bombardment treatment parameters are: argon: hydrogen flow ratio of 1:1, bombardment temperature of 470 to 490°C, and bombardment time of 1 to 2 hours; the nitriding process parameters are: nitrogen: hydrogen flow ratio of 2.8 to 3.2:1, furnace pressure: 260 to 270 Pa, temperature of 475 to 485°C, and insulation time of 23 to 25 hours.

[0021] As an optimization, the adhesive in step (3) is prepared by mixing modified polyimide and N,N-dimethylacetamide in a mass ratio of 1:3~5, standing at 45~55°C for 1.5~2.5h, heating to 115~125°C, standing for 1.5~2.5h, heating to 375~385°C at a rate of 40°C / h, maintaining for 3.5~4.5h, placing in deionized water, cooling to room temperature, filtering, vacuum drying at -10~0°C for 22~26h, grinding to 400 mesh, and preparing modified polyimide powder. The modified polyimide powder, bisphenol A epoxy resin, and acetone are uniformly mixed in a mass ratio of 18~22:78~82:5~7 to prepare the adhesive.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] In the preparation of a bend-resistant and highly thermally conductive aluminum-based copper-clad laminate, the present invention comprises the following steps: first reacting 2,7-dinitro-9-fluorenone with resorcinol, and then converting the nitro group into an amino group to obtain a modified monomer; then polymerizing the modified monomer, diphenylhexafluoroisopropyl tetracarboxylic dianhydride, 3,3′,4,4′-dibenzophenone tetracarboxylic dianhydride, and N-methylpyrrolidone, and then reacting the polymer with 1-aminomethylmaleimide hydrochloride to obtain a modified polyimide; then nitriding an aluminum sheet and reacting the polymer with allyltrimethoxysilane, 4-(aminomethyl)-2-(tert-butyl)phenol, and furan, 2-(2-chloroethyl) in sequence to obtain a functionalized aluminum sheet; then thermally polymerizing the modified polyimide and mixing it with bisphenol A epoxy resin and acetone; then bonding a rolled copper foil and the functionalized aluminum sheet, and hot pressing the polymer to obtain the bend-resistant and highly thermally conductive aluminum-based copper-clad laminate.

[0024] First, 2,7-dinitro-9-fluorenone is reacted with resorcinol, and then the nitro group is converted into an amino group to obtain a modified monomer; the modified monomer, diphenylhexafluoroisopropyl tetracarboxylic acid dianhydride, 3,3′,4,4′-dibenzophenone tetracarboxylic acid dianhydride, and N-methylpyrrolidone are polymerized and then reacted with 1-aminomethylmaleimide hydrochloride to obtain a modified polyimide; 2,7-dinitro-9-fluorenone is reacted with resorcinol, and then the nitro group is converted into an amino group to obtain a hydroxyl-containing modified monomer, which can be used as a curing agent for epoxy resin; the modified monomer, diphenylhexafluoroisopropyl tetracarboxylic acid dianhydride, 3,3′,4,4′-dibenzophenone tetracarboxylic acid dianhydride, and N-methylpyrrolidone are polymerized to obtain a fluorine-containing polyimide, which can significantly reduce the surface tension of the adhesive, thereby achieving waterproofing. The effect is effective, thereby preventing moisture from penetrating into the circuit board, protecting the circuit board from erosion in a humid environment, preventing moisture from damaging electronic components, and avoiding degradation of the electrical performance of the circuit board and material expansion; and polymaleimide can fill the microcracks and pores formed in the epoxy resin during the curing process, reducing the diffusion path of the corrosive medium; and then reacting with 1-aminomethylmaleimide hydrochloride to introduce maleimide, and through its DA reaction with furan on the epoxy resin, cyclohexene with a substituent is formed to form a thermally reversible dynamic covalent bond. The bond formation and breaking conditions are mild and there are few side reactions, so that the adhesive has a self-repairing effect, which automatically repairs tiny cracks and damage when the material is damaged, thereby reducing material failure caused by accumulation of tiny damage and extending the service life of the material.

[0025] Secondly, the aluminum sheet is nitrided and then reacted with allyltrimethoxysilane, 4-(aminomethyl)-2-(tert-butyl)phenol and furan, 2-(2-chloroethyl) in sequence to obtain a functionalized aluminum sheet; the modified polyimide is thermally polymerized and mixed with bisphenol A epoxy resin and acetone, the rolled copper foil and the functionalized aluminum sheet are bonded and hot pressed to obtain a bending-resistant and highly thermally conductive aluminum-based copper-clad laminate; the aluminum sheet is nitrided to form a layer of aluminum nitride on the surface, which can greatly improve the thermal conductivity of the material; it is then reacted with allyltrimethoxysilane and 4-(aminomethyl)-2-(tert-butyl)phenol to introduce hindered phenol on the surface of the material. Due to the hydroxyl groups on the hindered phenol, The radicals are restricted by spatial barriers, and hydrogen atoms are easily detached from the original molecular structure and combined with peroxy radicals, alkyl radicals, hydroxyl radicals, etc., causing them to lose their original activity, thereby terminating the oxygen aging reaction and extending the service life of the insulation layer; the modified polyimide is thermally polymerized to form a triazine ring. The triazine ring has a high degree of planarity and a rigid structure. This structure makes the molecule less likely to deform at high temperatures, thereby maintaining the mechanical strength and stability of the material. The carbon-nitrogen bond in the triazine ring is a relatively stable chemical bond that can remain intact at high temperatures and is not easily broken. The stability of this bond further enhances the heat resistance of the insulation layer. DETAILED DESCRIPTION

[0026] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0027] Example 1:

[0028] A method for preparing a bending-resistant and highly thermally conductive aluminum-based copper-clad laminate mainly comprises the following preparation steps:

[0029] (1) 2,7-Dinitro-9-fluorenone and resorcinol were mixed in a molar ratio of 1:2.4. Under argon protection, p-toluenesulfonic acid (1.4 times the molar amount of 2,7-Dinitro-9-fluorenone) was added. The mixture was stirred at 200 r / min and 135 ° C for 5 h. After cooling to room temperature, methanol (4 times the molar amount of 2,7-Dinitro-9-fluorenone) was added. The mixture was stirred at 200 r / min for 8 min. The mixture was poured into deionized water, allowed to stand for 20 min, filtered, washed with deionized water 3 times, and vacuum dried at -10 ° C for 22 h to obtain a pre-modified monomer.

[0030] Ethanol and water were mixed uniformly in a volume ratio of 2.8:1 to prepare an ethanol aqueous solution; a pre-modified monomer, 200 mesh zinc powder, and ammonium chloride were mixed uniformly in a molar ratio of 1:11:3.5, and an ethanol aqueous solution with a molar amount 12 times that of the pre-modified monomer and glacial acetic acid with a molar amount 4.2 times that of the pre-modified monomer were added, and the mixture was stirred at 200 r / min, 58° C., and argon protection for 6 hours, filtered, washed with deionized water 3 times, and vacuum dried at -10° C. for 22 hours to prepare a modified monomer;

[0031] The modified monomer, diphenyl hexafluoroisopropyl tetracarboxylic dianhydride, 3,3′,4,4′-dibenzophenone tetracarboxylic dianhydride, N-methylpyrrolidone and isoquinoline were mixed in a molar ratio of 8:6:3:30:0.01, stirred at 200 r / min for 50 min, heated to 175°C at 40°C / h, stirred for 46 h, cooled to room temperature, 0.38 times the molar amount of 4-aminobenzonitrile of the modified monomer was added, and the mixture was stirred for 50 min. The mixture was heated to 175°C at 40°C / h, stirred for 22 h, cooled to room temperature, poured into ethanol, filtered, washed with ethanol three times, and vacuum dried at 55°C for 5 h to obtain a pre-modified polyimide.

[0032] The pre-modified polyimide, 1-aminomethylmaleimide hydrochloride and toluene were mixed in a mass ratio of 4:20:1, stirred at 150°C and 200 r / min for 22 h, cooled to room temperature, filtered, washed with deionized water three times, and vacuum dried at 55°C for 11 h to prepare the modified polyimide;

[0033] (2) An aluminum sheet with a thickness of 1 mm was polished to 0.8 mm using silicon carbide sandpaper of models P1000, P1500, and P2000, polished with W1 diamond polishing agent, ultrasonicated in ethanol for 8 minutes, vacuum dried at 50°C for 6 hours, and placed in a fully automatic pulse power ion nitriding furnace. The bombardment treatment parameters were: argon: hydrogen flow ratio of 1:1, bombardment temperature of 470°C, and bombardment time of 1 hour; the nitriding process parameters were: nitrogen: hydrogen flow ratio of 2.8:1, furnace pressure of 260 Pa, temperature of 475°C, and holding time of 23 hours; and an aluminum sheet containing an aluminum nitride layer on the surface was obtained;

[0034] Allyltrimethoxysilane and isopropyl alcohol were mixed in a mass ratio of 1:8, and the pH was adjusted to 4 with a 0.1 mol / L acetic acid aqueous solution to prepare a surface treatment liquid. The surface treatment liquid was evenly applied to an aluminum sheet containing an aluminum nitride layer on the surface, and allowed to stand at 85°C for 5 hours. The application and drying were repeated 5 times, and the sheet was washed with deionized water 6 times and dried at 40°C for 22 hours to prepare a pre-modified aluminum sheet.

[0035] The pre-modified aluminum sheet, ethanol and 4-(aminomethyl)-2-(tert-butyl)phenol were mixed in a mass ratio of 1:4:0.28, ultrasonicated at 45°C under argon protection for 1.5 hours, taken out, washed with deionized water three times, and dried at 40°C for 11 hours to obtain a modified aluminum sheet;

[0036] Furan, 2-(2-chloroethyl), dimethyl sulfoxide and modified aluminum flakes were mixed in a mass ratio of 1:8:3, ultrasonicated at 85°C for 11 h, taken out, washed three times with deionized water, and dried at 40°C for 11 h to prepare functionalized aluminum flakes.

[0037] (3) Modified polyimide and N,N-dimethylacetamide were mixed in a mass ratio of 1:3, allowed to stand at 45 °C for 1.5 h, heated to 115 °C, allowed to stand for 1.5 h, heated to 375 °C at a rate of 40 °C / h, maintained for 3.5 h, placed in deionized water, cooled to room temperature, filtered, vacuum dried at -10 °C for 22 h, and ground to 400 mesh to obtain modified polyimide powder. Modified polyimide powder, bisphenol A epoxy resin and acetone were mixed in a mass ratio of The adhesive was evenly mixed at 18:78:5 to prepare an adhesive; the adhesive was applied on the surface of a polypropylene film with a thickness of 48 μm, dried at 80°C for 4.5 minutes, cooled to room temperature, and a 0.6 mm thick rolled copper foil was pasted on the surface, and laminated at 115°C for 3 minutes. The polypropylene film was peeled off, and a functionalized aluminum sheet was pasted on the surface. The film was placed in a hot press with a pressure of 0.16 MPa, heated to 170°C, kept warm for 80 minutes, and naturally cooled to room temperature to prepare an aluminum-based copper clad laminate.

[0038] Example 2:

[0039] A method for preparing a bending-resistant and highly thermally conductive aluminum-based copper-clad laminate mainly comprises the following preparation steps:

[0040] (1) 2,7-dinitro-9-fluorenone and resorcinol were mixed in a molar ratio of 1:2.5. Under argon protection, p-toluenesulfonic acid (1.5 times the molar amount of 2,7-dinitro-9-fluorenone) was added. The mixture was stirred at 250 r / min and 140 ° C for 6 h. After cooling to room temperature, methanol (4.5 times the molar amount of 2,7-dinitro-9-fluorenone) was added. The mixture was stirred at 250 r / min for 9 min. The mixture was poured into deionized water, allowed to stand for 25 min, filtered, washed with deionized water 4 times, and vacuum dried at -5 ° C for 24 h to obtain a pre-modified monomer.

[0041] Ethanol and water were mixed uniformly in a volume ratio of 3:1 to prepare an ethanol aqueous solution; a pre-modified monomer, 200-mesh zinc powder, and ammonium chloride were mixed uniformly in a molar ratio of 1:12:4, and an ethanol aqueous solution with a molar amount of 12.5 times that of the pre-modified monomer and glacial acetic acid with a molar amount of 4.4 times that of the pre-modified monomer were added, and the mixture was stirred at 250 r / min, 60° C., and argon protection for 6.5 hours, filtered, washed with deionized water 4 times, and vacuum dried at -5° C. for 24 hours to prepare a modified monomer;

[0042] The modified monomer, diphenyl hexafluoroisopropyl tetracarboxylic dianhydride, 3,3′,4,4′-dibenzophenone tetracarboxylic dianhydride, N-methylpyrrolidone and isoquinoline were mixed in a molar ratio of 9:6.5:3.5:35:0.01, stirred at 250 r / min for 60 min, heated to 180°C at 40°C / h, stirred for 48 h, cooled to room temperature, 0.4 times the molar amount of 4-aminobenzonitrile of the modified monomer was added, and the mixture was stirred for 60 min. The mixture was heated to 180°C at 40°C / h, stirred for 24 h, cooled to room temperature, poured into ethanol, filtered, washed with ethanol 4 times, and vacuum dried at 60°C for 6 h to obtain a pre-modified polyimide.

[0043] The pre-modified polyimide, 1-aminomethylmaleimide hydrochloride and toluene were mixed in a mass ratio of 5:25:1, stirred at 160°C and 250 r / min for 24 h, cooled to room temperature, filtered, washed with deionized water 4 times, and vacuum dried at 60°C for 12 h to prepare the modified polyimide;

[0044] (2) An aluminum sheet with a thickness of 1 mm was polished to 0.8 mm using silicon carbide sandpaper of models P1000, P1500, and P2000, polished using W1 diamond polishing agent, ultrasonicated in ethanol for 10 min, vacuum dried at 55 ° C for 7 h, and placed in a fully automatic pulse power ion nitriding furnace. The bombardment treatment parameters were: argon: hydrogen flow ratio of 1:1, bombardment temperature of 480 ° C, and bombardment time of 1.5 h; the nitriding process parameters were: nitrogen: hydrogen flow ratio of 3:1, furnace pressure: 265 Pa, temperature of 480 ° C, and holding time of 24 h; an aluminum sheet containing an aluminum nitride layer on the surface was obtained;

[0045] Allyltrimethoxysilane and isopropyl alcohol were mixed in a mass ratio of 1:10, and the pH was adjusted to 5 with a 0.1 mol / L acetic acid aqueous solution to prepare a surface treatment liquid. The surface treatment liquid was evenly applied to an aluminum sheet containing an aluminum nitride layer on the surface, and the mixture was allowed to stand at 90°C for 6 hours. The application and drying were repeated 5 times, and the mixture was washed with deionized water 7 times. The mixture was dried at 45°C for 23 hours to prepare a pre-modified aluminum sheet.

[0046] The pre-modified aluminum sheet, ethanol and 4-(aminomethyl)-2-(tert-butyl)phenol were mixed in a mass ratio of 1:5:0.3, ultrasonicated at 50°C under argon protection for 2 hours, taken out, washed with deionized water 4 times, and dried at 45°C for 12 hours to obtain a modified aluminum sheet;

[0047] Furan, 2-(2-chloroethyl), dimethyl sulfoxide and modified aluminum flakes were mixed in a mass ratio of 1:10:4, ultrasonicated at 90°C for 12 h, taken out, washed with deionized water four times, and dried at 45°C for 12 h to prepare functionalized aluminum flakes.

[0048] (3) The modified polyimide and N,N-dimethylacetamide were mixed in a mass ratio of 1:4, allowed to stand at 50°C for 2 h, raised to 120°C, allowed to stand for 2 h, raised to 380°C at a rate of 40°C / h, maintained for 4 h, placed in deionized water, cooled to room temperature, filtered, vacuum dried at -5°C for 24 h, and ground to 400 mesh to obtain modified polyimide powder. The modified polyimide powder, bisphenol A epoxy resin and acetone were mixed in a mass ratio of 20: The adhesive was evenly mixed in an amount of 80:5 to obtain an adhesive; the adhesive was applied on the surface of a polypropylene film with a thickness of 50 μm, dried at 85°C for 5 minutes, cooled to room temperature, and a 0.6 mm thick rolled copper foil was pasted on the surface, and laminated at 120°C for 4 minutes. The polypropylene film was peeled off, and a functionalized aluminum sheet was pasted on the surface. The film was placed in a hot press with a pressure of 0.16 MPa, heated to 175°C, kept warm for 90 minutes, and naturally cooled to room temperature to obtain an aluminum-based copper clad laminate.

[0049] Example 3:

[0050] A method for preparing a bending-resistant and highly thermally conductive aluminum-based copper-clad laminate mainly comprises the following preparation steps:

[0051] (1) 2,7-Dinitro-9-fluorenone and resorcinol were mixed in a molar ratio of 1:2.6. Under argon protection, p-toluenesulfonic acid (1.6 times the molar amount of 2,7-Dinitro-9-fluorenone) was added. The mixture was stirred at 300 r / min and 145 °C for 7 h. After cooling to room temperature, methanol (5 times the molar amount of 2,7-Dinitro-9-fluorenone) was added. The mixture was stirred at 300 r / min for 10 min. The mixture was poured into deionized water, allowed to stand for 30 min, filtered, washed with deionized water 5 times, and vacuum dried at 0 °C for 26 h to obtain a pre-modified monomer.

[0052] Ethanol and water were mixed uniformly in a volume ratio of 3.2:1 to prepare an ethanol aqueous solution; a pre-modified monomer, 200 mesh zinc powder, and ammonium chloride were mixed uniformly in a molar ratio of 1:13:4.5, and an ethanol aqueous solution with a molar amount 13 times that of the pre-modified monomer and glacial acetic acid with a molar amount 4.6 times that of the pre-modified monomer were added, and the mixture was stirred at 300 r / min, 62° C., and argon protection for 7 h, filtered, washed with deionized water 5 times, and vacuum dried at 0° C. for 26 h to prepare a modified monomer;

[0053] The modified monomer, diphenylhexafluoroisopropyl tetracarboxylic dianhydride, 3,3′,4,4′-dibenzophenone tetracarboxylic dianhydride, N-methylpyrrolidone and isoquinoline were mixed in a molar ratio of 10:7:4:40:0.01, stirred at 300 r / min for 70 min, heated to 185°C at 40°C / h, stirred for 50 h, cooled to room temperature, 0.42 times the molar amount of 4-aminobenzonitrile of the modified monomer was added, and the mixture was stirred for 70 min. The mixture was heated to 185°C at 40°C / h, stirred for 26 h, cooled to room temperature, poured into ethanol, filtered, washed with ethanol 5 times, and vacuum dried at 65°C for 7 h to obtain a pre-modified polyimide.

[0054] The pre-modified polyimide, 1-aminomethylmaleimide hydrochloride and toluene were mixed in a mass ratio of 6:30:1, stirred at 170°C and 300 r / min for 26 hours, cooled to room temperature, filtered, washed with deionized water 5 times, and vacuum dried at 65°C for 13 hours to prepare the modified polyimide;

[0055] (2) An aluminum sheet with a thickness of 1 mm was polished to 0.8 mm using silicon carbide sandpaper of models P1000, P1500, and P2000, polished with W1 diamond polishing agent, ultrasonicated in ethanol for 12 minutes, vacuum dried at 60°C for 8 hours, and placed in a fully automatic pulse power ion nitriding furnace. The bombardment treatment parameters were: argon: hydrogen flow ratio of 1:1, bombardment temperature of 490°C, and bombardment time of 2 hours; the nitriding process parameters were: nitrogen: hydrogen flow ratio of 3.2:1, furnace pressure of 270 Pa, temperature of 485°C, and holding time of 25 hours; and an aluminum sheet containing an aluminum nitride layer on the surface was obtained.

[0056] Allyltrimethoxysilane and isopropyl alcohol were mixed in a mass ratio of 1:12, and the pH was adjusted to 6 with a 0.1 mol / L acetic acid aqueous solution to prepare a surface treatment liquid. The surface treatment liquid was evenly applied to an aluminum sheet containing an aluminum nitride layer on the surface, and the mixture was allowed to stand at 95°C for 7 hours. The application and drying were repeated 5 times, and the mixture was washed with deionized water 8 times. The mixture was dried at 50°C for 24 hours to prepare a pre-modified aluminum sheet.

[0057] The pre-modified aluminum sheet, ethanol and 4-(aminomethyl)-2-(tert-butyl)phenol were mixed in a mass ratio of 1:6:0.32, ultrasonicated at 55°C under argon protection for 2.5 hours, taken out, washed with deionized water 5 times, and dried at 50°C for 13 hours to obtain a modified aluminum sheet;

[0058] Furan, 2-(2-chloroethyl), dimethyl sulfoxide and modified aluminum flakes were mixed in a mass ratio of 1:12:5, ultrasonicated at 95°C for 13 h, taken out, washed with deionized water 5 times, and dried at 50°C for 13 h to prepare functionalized aluminum flakes.

[0059] (3) Modified polyimide and N,N-dimethylacetamide were mixed in a mass ratio of 1:5, allowed to stand at 55 °C for 2.5 h, heated to 125 °C, allowed to stand for 2.5 h, heated to 385 °C at a rate of 40 °C / h, maintained for 4.5 h, placed in deionized water, cooled to room temperature, filtered, vacuum dried at 0 °C for 26 h, and ground to 400 mesh to obtain modified polyimide powder. Modified polyimide powder, bisphenol A epoxy resin and acetone were mixed in a mass ratio of 22 :82:7 are mixed evenly to prepare an adhesive; the adhesive is applied on the surface of a polypropylene film with a thickness of 52 μm, dried at 90°C for 5.5 minutes, cooled to room temperature, and a 0.6 mm thick rolled copper foil is pasted on the surface, and laminated at 125°C for 5 minutes. The polypropylene film is peeled off, and a functionalized aluminum sheet is pasted on the surface. The film is placed in a hot press and pressurized at 0.16 MPa, heated to 180°C, kept warm for 100 minutes, and naturally cooled to room temperature to prepare an aluminum-based copper clad laminate.

[0060] Comparative Example 1:

[0061] The difference between the preparation method of the bending-resistant and high-thermal-conductivity aluminum-based copper-clad laminate of Comparative Example 1 and Example 2 lies in the difference in step (1). Step (1) is modified as follows: 2,7-dinitro-9-fluorenone and resorcinol are mixed in a molar ratio of 1:2.5, and under argon protection, p-toluenesulfonic acid is added in an amount 1.5 times the molar amount of 2,7-dinitro-9-fluorenone, and stirred at 250 r / min and 140°C for 6 hours. The mixture is cooled to room temperature, and methanol is added in an amount 4.5 times the molar amount of 2,7-dinitro-9-fluorenone, and stirred at 250 r / min for 9 minutes. The mixture is poured into deionized water, allowed to stand for 25 minutes, filtered, washed with deionized water 4 times, and vacuum dried at -5°C for 24 hours to obtain a pre-modified monomer.

[0062] Ethanol and water were mixed uniformly in a volume ratio of 3:1 to prepare an ethanol aqueous solution; a pre-modified monomer, 200-mesh zinc powder, and ammonium chloride were mixed uniformly in a molar ratio of 1:12:4, and an ethanol aqueous solution with a molar amount of 12.5 times that of the pre-modified monomer and glacial acetic acid with a molar amount of 4.4 times that of the pre-modified monomer were added, and the mixture was stirred at 250 r / min, 60° C., and argon protection for 6.5 hours, filtered, washed with deionized water 4 times, and vacuum dried at -5° C. for 24 hours to prepare a modified monomer;

[0063] The modified monomer, diphenylhexafluoroisopropyl tetracarboxylic dianhydride, 3,3',4,4'-benzophenone tetracarboxylic dianhydride, N-methylpyrrolidone, and isoquinoline were mixed in a molar ratio of 9:6.5:3.5:35:0.01, stirred at 250 r / min for 60 min, heated to 180°C at 40°C / h, stirred for 48 h, cooled to room temperature, and 4-aminobenzonitrile (0.4 times the molar amount of the modified monomer) was added. Stirring was continued for 60 min, heated to 180°C at 40°C / h, stirred for 24 h, cooled to room temperature, poured into ethanol, filtered, washed four times with ethanol, and vacuum dried at 60°C for 6 h to produce a modified polyimide. The remaining steps were the same as in Example 2.

[0064] Comparative Example 2:

[0065] The preparation method of the bending-resistant and high-thermal-conductivity aluminum-based copper-clad laminate of Comparative Example 2 differs from that of Example 2 in that step (1) is different. Step (1) is modified as follows: 2,7-dinitro-9-fluorenone and resorcinol are mixed in a molar ratio of 1:2.5, and under argon protection, p-toluenesulfonic acid is added in an amount 1.5 times the molar amount of 2,7-dinitro-9-fluorenone, and stirred at 250 r / min and 140°C for 6 h. The mixture is cooled to room temperature, and methanol is added in an amount 4.5 times the molar amount of 2,7-dinitro-9-fluorenone, and stirred at 250 r / min for 9 min. The mixture is poured into deionized water, allowed to stand for 25 min, filtered, washed with deionized water 4 times, and vacuum dried at -5°C for 24 h to obtain a pre-modified monomer.

[0066] Ethanol and water were mixed uniformly in a volume ratio of 3:1 to prepare an ethanol aqueous solution; a pre-modified monomer, 200-mesh zinc powder, and ammonium chloride were mixed uniformly in a molar ratio of 1:12:4, and an ethanol aqueous solution with a molar amount of 12.5 times that of the pre-modified monomer and glacial acetic acid with a molar amount of 4.4 times that of the pre-modified monomer were added, and the mixture was stirred at 250 r / min, 60° C., and argon protection for 6.5 hours, filtered, washed with deionized water 4 times, and vacuum dried at -5° C. for 24 hours to prepare a modified monomer;

[0067] The modified monomer, 3,3′,4,4′-benzophenone tetracarboxylic dianhydride, N-methylpyrrolidone, and isoquinoline were mixed in a molar ratio of 9:10:35:0.01, stirred at 250 r / min for 60 min, heated to 180°C at 40°C / h, stirred for 48 h, and cooled to room temperature. 4-aminobenzonitrile (0.4 times the molar amount of the modified monomer) was added, stirred for a further 60 min, heated to 180°C at 40°C / h, stirred for 24 h, cooled to room temperature, poured into ethanol, filtered, washed four times with ethanol, and vacuum dried at 60°C for 6 h to produce a modified polyimide. The remaining steps were the same as in Example 2.

[0068] Comparative Example 3:

[0069] The difference between the preparation method of the bending-resistant and high-thermal-conductivity aluminum-based copper-clad laminate of Comparative Example 3 and Example 2 lies in the difference in step (2). Step (2) is modified as follows: an aluminum sheet with a thickness of 1 mm is polished to 0.8 mm using silicon carbide sandpaper of models P1000, P1500, and P2000 in sequence, polished using W1 diamond polishing agent, ultrasonicated in ethanol for 10 minutes, vacuum dried at 55°C for 7 hours, placed in a fully automatic pulse power supply ion nitriding furnace, bombardment treatment parameters: argon: hydrogen flow ratio of 1:1, bombardment temperature of 480°C, bombardment time of 1.5 hours; nitriding process parameters: nitrogen: hydrogen flow ratio of 3:1, furnace pressure: 265Pa, temperature of 480°C, holding time of 24 hours; to obtain an aluminum sheet containing an aluminum nitride layer on the surface;

[0070] Allyltrimethoxysilane and isopropyl alcohol were mixed in a mass ratio of 1:10, and the pH was adjusted to 5 with a 0.1 mol / L acetic acid aqueous solution to prepare a surface treatment liquid. The surface treatment liquid was evenly applied to an aluminum sheet containing an aluminum nitride layer on the surface, and the mixture was allowed to stand at 90°C for 6 hours. The application and drying were repeated 5 times, and the mixture was washed with deionized water 7 times. The mixture was dried at 45°C for 23 hours to prepare a pre-modified aluminum sheet.

[0071] The pre-modified aluminum sheet, ethanol, and 4-(aminomethyl)-2-(tert-butyl)phenol were mixed in a mass ratio of 1:5:0.3, and ultrasonicated at 50°C under argon for 2 hours. The sheet was removed, washed four times with deionized water, and dried at 45°C for 12 hours to produce a functionalized aluminum sheet. The remaining steps were the same as in Example 2.

[0072] Comparative Example 4:

[0073] The preparation method of the bending-resistant and high-thermal-conductivity aluminum-based copper-clad laminate of Comparative Example 4 differs from that of Example 2 in that step (2) is modified as follows: an aluminum sheet having a thickness of 1 mm is polished to 0.8 mm using silicon carbide sandpaper of types P1000, P1500, and P2000 in sequence, polished using W1 diamond polishing agent, ultrasonicated in ethanol for 10 min, vacuum dried at 55° C. for 7 h, and placed in a fully automatic pulse power supply ion nitriding furnace with bombardment treatment parameters: argon:hydrogen flow ratio of 1:1, bombardment temperature of 480° C., and bombardment time of 1.5 h; and nitriding process parameters: nitrogen:hydrogen flow ratio of 3:1, furnace pressure of 265 Pa, temperature of 480° C., and holding time of 24 h; thereby obtaining a functionalized aluminum sheet. The remaining steps are the same as those of Example 2.

[0074] Comparative Example 5:

[0075] The method for preparing the bending-resistant, high-thermal-conductivity aluminum-based copper-clad laminate of Comparative Example 5 differs from that of Example 2 in step (2). Step (2) is modified as follows: a 1 mm thick aluminum sheet is polished to 0.8 mm using silicon carbide sandpaper of types P1000, P1500, and P2000, respectively, polished using W1 diamond polishing agent, ultrasonically treated in ethanol for 10 min, and vacuum-dried at 55° C. for 7 h to obtain a functionalized aluminum sheet. The remaining steps are the same as those of Example 2.

[0076] Comparative Example 6:

[0077] The preparation method of the bending-resistant and high-thermal-conductivity aluminum-based copper-clad laminate of Comparative Example 6 is different from that of Example 2 in that steps (1) and (3) are different. Step (1) is modified as follows: 2,7-dinitro-9-fluorenone and resorcinol are mixed in a molar ratio of 1:2.5, and under argon protection, p-toluenesulfonic acid with a molar amount of 1.5 times that of 2,7-dinitro-9-fluorenone is added, and stirred at 250 r / min and 140°C for 6 hours, cooled to room temperature, and methanol with a molar amount of 4.5 times that of 2,7-dinitro-9-fluorenone is added, and stirred at 250 r / min for 9 minutes, poured into deionized water, allowed to stand for 25 minutes, filtered, washed with deionized water 4 times, and vacuum dried at -5°C for 24 hours. h, to prepare the pre-modified monomer; ethanol and water were mixed in a volume ratio of 3:1 to prepare an ethanol aqueous solution; the pre-modified monomer, 200 mesh zinc powder, and ammonium chloride were mixed in a molar ratio of 1:12:4, and an ethanol aqueous solution with a molar amount of 12.5 times that of the pre-modified monomer and glacial acetic acid with a molar amount of 4.4 times that of the pre-modified monomer were added, and stirred at 250r / min, 60℃, and argon protection for 6.5h, filtered, washed with deionized water 4 times, and vacuum dried at -5℃ for 24h to prepare the modified monomer; the modified monomer, diphenylhexafluoroisopropyl tetracarboxylic dianhydride, 3,3',4,4'-dibenzophenone tetracarboxylic dianhydride, N-methylpyrrolidone and isoquinoline were mixed in a molar ratio of 9:6.5:3.5:3 The pre-modified polyimide was prepared by mixing the pre-modified polyimide with 1-aminomethylmaleimide hydrochloride and toluene in a mass ratio of 5:25:1, stirring at 160°C and 250r / min for 24h, cooling to room temperature, adding aniline in an amount of 0.4 times the molar amount of the modified monomer, continuing to stir for 60min, heating to 180°C at 40°C / h, stirring for 24h, cooling to room temperature, pouring into ethanol, filtering, washing with ethanol 4 times, and vacuum drying at 60°C for 6h to obtain the pre-modified polyimide; the pre-modified polyimide, 1-aminomethylmaleimide hydrochloride and toluene were mixed in a mass ratio of 5:25:1, stirring at 160°C and 250r / min for 24h, cooling to room temperature, filtering, washing with deionized water 4 times, and drying at 60°C. The modified polyimide was vacuum dried for 12 hours to obtain a modified polyimide. Step (3) was modified to grind the modified polyimide to 400 mesh to obtain a modified polyimide powder. The modified polyimide powder, bisphenol A epoxy resin, and acetone were mixed uniformly in a mass ratio of 20:80:5 to obtain an adhesive. The adhesive was applied to the surface of a polypropylene film to a thickness of 50 μm, dried at 85°C for 5 minutes, cooled to room temperature, and a 0.6 mm thick rolled copper foil was attached to the surface. The film was laminated at 120°C for 4 minutes, the polypropylene film was removed, and a functionalized aluminum sheet was attached. The film was placed in a hot press and pressurized at 0.16 MPa. The film was heated to 175°C, kept warm for 90 minutes, and naturally cooled to room temperature to obtain an aluminum-based copper-clad laminate. The remaining steps were the same as those in Example 2.

[0078] Test Example 1:

[0079] Bending test:

[0080] Test method: Tested in accordance with IPC-TM-6502.4.3 test standard. Results are shown in Table 1.

[0081] Table 1

[0082] Folding resistance Example 1 >10 times Example 2 >10 times Example 3 >10 times Comparative Example 1 >10 times Comparative Example 2 >10 times Comparative Example 3 >10 times Comparative Example 4 >10 times Comparative Example 5 >10 times Comparative Example 6 >10 times

[0083] From the comparison of the experimental data in Table 1, it can be found that the bending-resistant and high-thermal-conductivity aluminum-based copper-clad laminate prepared in the present invention has good bending resistance.

[0084] Test Example 2:

[0085] Thermal conductivity test:

[0086] Test method: Tested in accordance with ASTM D5470. Results are shown in Table 2.

[0087] Table 2

[0088] Thermal conductivity Example 1 3.38W / m·K Example 2 3.40W / m·K Example 3 3.41W / m·K Comparative Example 1 3.39W / m·K Comparative Example 2 3.37W / m·K Comparative Example 3 3.36W / m·K Comparative Example 4 3.38W / m·K Comparative Example 5 1.98W / m·K Comparative Example 6 3.39W / m·K

[0089] From the comparison of the experimental data in Table 2, it can be found that the bending-resistant and high-thermal-conductivity aluminum-based copper-clad laminate prepared in the present invention has good thermal conductivity.

[0090] From the comparison of the experimental data of Examples 1, 2, 3 and Comparative Example 5 in Table 2, it can be found that the thermal conductivity coefficients of Examples 1, 2, and 3 are large. The difference between Comparative Example 5 and the Examples is that no aluminum nitride is formed on the surface of the aluminum plate, which shows that aluminum nitride can greatly improve the thermal conductivity of the material.

[0091] Test Example 3:

[0092] Insulation test:

[0093] The adhesives prepared in each example and comparative example were evenly applied on a polytetrafluoroethylene plate with a thickness of 50 μm, a length of 15 cm, and a width of 3 cm. The plates were cured at 85° C., peeled off, and tested.

[0094] Aging resistance test: The tensile strength of the specimen is tested, recorded as J0, and the specimen is aged for three days at a temperature of 70°C and a humidity of 100%. The tensile strength is tested again, recorded as J1. Aging retention rate = J1 / J0 × 100%;

[0095] Self-healing test: The tensile strength of the specimen was tested, recorded as J0. A 2 cm long and 50 μm deep cut was made in the center of the specimen. The specimen was placed at 80°C for 24 h, cooled to room temperature, and the tensile strength was tested again, recorded as J2. The self-healing rate = J2 / J0 × 100%;

[0096] Waterproof test: test water contact angle;

[0097] High-temperature resistance testing: A TA Instruments Q500 thermogravimetric analyzer was used. Under a nitrogen atmosphere, the temperature was raised from room temperature to 120°C at a rate of 20°C / min, held for 20 minutes, then lowered to 100°C. A second heating cycle was performed, from 100°C to 800°C at a rate of 20°C / min, with a nitrogen flow rate of 50 mL / min. The 5% weight loss temperature was recorded. The results are shown in Table 3.

[0098] Table 3

[0099] Aging retention rate Self-repair rate Water contact angle 5% thermal weight loss temperature Example 1 98.8% 98.3% 108.3° 410.3℃ Example 2 99.0% 98.1% 108.6° 411.0℃ Example 3 98.9% 98.4% 108.5° 410.7℃ Comparative Example 1 98.6% 39.6% 108.4° 410.6℃ Comparative Example 2 98.7% 39.8% 89.2° 411.1℃ Comparative Example 3 98.5% 39.7% 108.2° 410.5℃ Comparative Example 4 96.2% 39.5% 108.3° 410.1℃ Comparative Example 5 96.1% 39.3% 108.5° 410.2℃ Comparative Example 6 98.7% 98.2% 108.2° 353.5℃

[0100] From the comparison of the experimental data in Table 3, it can be found that the bending-resistant and high-thermal-conductivity aluminum-based copper-clad laminate insulation layer prepared in the present invention has good aging resistance, self-repairing, heat resistance and waterproof capabilities.

[0101] From the comparison of the experimental data of Examples 1, 2, and 3 and Comparative Example 1 in Table 3, it can be found that the self-repair rates of Examples 1, 2, and 3 are large. The difference between Comparative Example 1 and the Example is that no maleimide structure is introduced into the polyimide, and no DA reaction can occur with furan. This shows that through the DA reaction of maleimide with furan on the epoxy resin, cyclohexene with a substituent can be formed, forming a thermally reversible dynamic covalent bond. The bond formation and breaking conditions are mild and there are few side reactions, thereby making the insulating layer have a self-repair effect.

[0102] From the comparison of the experimental data of Examples 1, 2, and 3 and Comparative Example 2, it can be found that the water contact angles of Examples 1, 2, and 3 are large. The difference between Comparative Example 2 and the Example is that no fluorine is added to the main chain of the polyimide. This shows that the addition of fluorine-containing polyimide can significantly reduce the surface tension of the insulating layer, thereby achieving a waterproof effect.

[0103] From the comparison of the experimental data of Examples 1, 2, 3 and Comparative Example 4, it can be found that the aging retention rates of Examples 1, 2, and 3 are large. The difference between Comparative Example 4 and the Example is that no hindered phenol is introduced on the surface of the aluminum plate. This shows that the hydroxyl groups on the hindered phenol are restricted by spatial barriers, and the hydrogen atoms are easily detached from the original molecular structure and combined with peroxyl radicals, alkyl radicals, hydroxyl radicals, etc., causing them to lose their original activity, thereby terminating the oxygen aging reaction and extending the service life of the insulation layer.

[0104] From the comparison of the experimental data of Examples 1, 2, 3 and Comparative Example 6, it can be found that the aging retention rates of Examples 1, 2, and 3 are large. The difference between Comparative Example 6 and the Examples is that the benzonitrile at both ends of the polyimide is not reacted to form triazine, which shows that the triazine ring has a high degree of planarity and a rigid structure. This structure makes the molecule less likely to deform at high temperatures, thereby maintaining the mechanical strength and stability of the material. The carbon-nitrogen bond in the triazine ring is a relatively stable chemical bond that can remain intact at high temperatures and is not easily broken. The stability of this bond further enhances the heat resistance of the insulating layer.

[0105] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for preparing a bending-resistant and highly thermally conductive aluminum-based copper-clad laminate, characterized in that: The preparation method of the bending-resistant and high-thermal-conductivity aluminum-based copper-clad laminate mainly includes the following preparation steps: (1) Mix 2,7-dinitro-9-fluorenone and resorcinol in a molar ratio of 1:2.4~2.

6. Under argon protection, add p-toluenesulfonic acid with a molar weight of 1.4~1.6 times that of 2,7-dinitro-9-fluorenone. Stir at 200~300 r / min and 135~145℃ for 5~7h. Cool to room temperature. Add methanol with a molar weight of 4~5 times that of 2,7-dinitro-9-fluorenone. Stir at 200~300 r / min for 8~10min. Pour deionized water into the mixture. The pre-modified monomer was prepared by mixing ethanol and water in a volume ratio of 2.8 to 3.2:1 to obtain an ethanol aqueous solution; the pre-modified monomer, 200 mesh zinc powder, and ammonium chloride were mixed in a molar ratio of 1:11 to 13:3.5 to 4.5, and an ethanol aqueous solution with a molar ratio of 12 to 13 times the mass of the pre-modified monomer and ice with a molar ratio of 4.2 to 4.6 times the mass of the pre-modified monomer were added. Acetic acid, at 200~300r / min, 58~62℃, under argon protection, stirred for 6~7h, filtered, washed with deionized water 3~5 times, and vacuum dried at -10~0℃ for 22~26h to prepare a modified monomer; the modified monomer, diphenylhexafluoroisopropyl tetracarboxylic dianhydride, 3,3',4,4'-dibenzophenone tetracarboxylic dianhydride, N-methylpyrrolidone and isoquinoline were mixed in a molar ratio of 8~10:6~7:3~4:30~40:0.01, and heated ... stirring at 40°C / h for 50-70 minutes, heating to 175-185°C at 40°C / h, stirring for 46-50 hours, cooling to room temperature, adding 4-aminobenzonitrile in an amount of 0.38-0.42 times the molar amount of the modified monomer, continuing stirring for 50-70 minutes, heating to 175-185°C at 40°C / h, stirring for 22-26 hours, cooling to room temperature, pouring into ethanol, filtering, washing with ethanol 3-5 times, and vacuum drying at 55-65°C for 5-7 hours to obtain a pre-modified polyimide; The pre-modified polyimide, 1-aminomethylmaleimide hydrochloride and toluene are mixed in a mass ratio of 4-6:20-30:1, stirred at 150-170°C and 200-300 r / min for 22-26 hours, cooled to room temperature, filtered, washed with deionized water 3-5 times, and vacuum dried at 55-65°C for 11-13 hours to prepare a modified polyimide; (2) Aluminum sheets with a thickness of 1 mm were polished to 0.8 mm using silicon carbide sandpaper of models P1000, P1500, and P2000, polished with W1 diamond polishing agent, ultrasonicated in ethanol for 8 to 12 minutes, vacuum dried at 50 to 60 ° C for 6 to 8 hours, and placed in a fully automatic pulse power ion nitriding furnace. The bombardment treatment parameters were: argon: hydrogen flow ratio of 1:1, bombardment temperature of 470 to 490 ° C, and bombardment time of 1 to 2 hours; nitriding process parameters were: nitrogen: hydrogen flow ratio of 2.8 to 3.2:1, furnace pressure of 260 ~270Pa, temperature 475~485℃, holding time 23~25h, to prepare an aluminum sheet with an aluminum nitride layer on the surface; allyltrimethoxysilane and isopropyl alcohol are mixed in a mass ratio of 1:8~12, and the pH is adjusted to 4~6 with a 0.1mol / L acetic acid aqueous solution to prepare a surface treatment liquid; the surface treatment liquid is evenly applied to the aluminum sheet with the aluminum nitride layer on the surface, and allowed to stand at 85~95℃ for 5~7h, and the application and drying are repeated 5 times, and the sheet is washed with deionized water 6~8 times, and dried at 40~50℃ for 22~24h to prepare a pre-modified aluminum sheet. The pre-modified aluminum sheet, ethanol and 4-(aminomethyl)-2-(tert-butyl)phenol were mixed in a mass ratio of 1:4-6:0.28-0.32, ultrasonicated at 45-55°C under argon protection for 1.5-2.5 hours, taken out, washed with deionized water 3-5 times, and dried at 40-50°C for 11-13 hours to prepare a modified aluminum sheet; furan, 2-(2-chloroethyl), dimethyl sulfoxide and the modified aluminum sheet were mixed in a mass ratio of 1:8-12:3-5, ultrasonicated at 85-95°C for 11-13 hours, taken out, washed with deionized water 3-5 times, and dried at 40-50°C for 11-13 hours to prepare a functionalized aluminum sheet; (3) Modified polyimide and N,N-dimethylacetamide were mixed in a mass ratio of 1:3~5, allowed to stand at 45~55℃ for 1.5~2.5h, heated to 115~125℃, allowed to stand for 1.5~2.5h, heated to 375~385℃ at a rate of 40℃ / h, maintained for 3.5~4.5h, placed in deionized water, cooled to room temperature, filtered, vacuum dried at -10~0℃ for 22~26h, ground to 400 mesh, and prepared modified polyimide powder. Modified polyimide powder, bisphenol A epoxy resin and acetone were mixed in a mass ratio of 18~2 The method comprises the following steps: uniformly mixing the adhesive in a ratio of 2:78~82:5~7 to prepare an adhesive; applying the adhesive on a surface of a polypropylene film with a thickness of 48~52 μm, drying the film at 80~90°C for 4.5~5.5 minutes, cooling the film to room temperature, pasting a rolled copper foil with a thickness of 0.6 mm on the surface, laminating the film at 115~125°C for 3~5 minutes, peeling off the polypropylene film, pasting a functionalized aluminum sheet on the adhesive layer, placing the film in a hot press under a pressure of 0.16 MPa, heating the film to 170~180°C, keeping the temperature for 80~100 minutes, and naturally cooling the film to room temperature to prepare an aluminum-based copper clad laminate.