1. The high-thermal-conductivity polyimide film is characterized by comprising the following raw materials in parts by weight: 35.4 to 50.6 portions of diamine monomer, 200 portions of aprotic polar solvent 120-one, 41.2 to 62.1 portions of aromatic dianhydride monomer, 4.5 to 10.6 portions of heat-conducting filler and 0.5 to 1.1 portions of dispersant;

wherein the diamine monomer is prepared by the following steps:

step S1, adding 4 '-chloro-4-nitro- [1, 1' -biphenyl]-2-carbonitrile, K₂HPO₄Mixing the N, N-dimethylacetamide uniformly, cooling to 0 ℃, adding trifluoromethanesulfonyl chloride, performing light source irradiation reaction for 7-8 hours, adding deionized water, extracting with ethyl acetate, combining organic phases, washing, drying and performing rotary evaporation to obtain an intermediate 1;

step S2, mixing the intermediate 1, sodium sulfide nonahydrate and N, N-dimethylacetamide, heating to 170 ℃ for reaction for 24 hours, filtering, washing a filter cake with water, and drying to obtain an intermediate 2;

step S3, mixing the intermediate 2, glacial acetic acid and potassium permanganate, heating to 80 ℃ to react for 2 hours, filtering, adding deionized water into the filtrate to precipitate a crude product, and recrystallizing to obtain an intermediate 3;

and step S4, mixing the intermediate 3, a palladium-carbon catalyst and absolute ethyl alcohol, adding hydrazine hydrate, heating to 70-75 ℃ for reaction, filtering, evaporating the solvent from the filtrate, and recrystallizing to obtain a diamine monomer.

2. The polyimide film with high thermal conductivity according to claim 1, wherein: the wavelength of the light source in step S1 is 280-780 nm.

3. The polyimide film with high thermal conductivity according to claim 1, wherein: the heat-conducting filler is prepared by the following steps:

and dispersing the acidified carbon nano tube in DMF (dimethyl formamide), ultrasonically dispersing, adding hydroxylated zinc oxide, heating to 80 ℃, reacting for 20-22h, and washing by dichloromethane to obtain the heat-conducting filler.

4. The polyimide film with high thermal conductivity according to claim 3, wherein: the hydroxylated zinc oxide is prepared by the following steps:

adding zinc oxide into sodium hydroxide solution, heating to 90 ℃, stirring for reaction for 30-40min, centrifuging, washing precipitate with acetone, and drying to obtain hydroxylated zinc oxide.

5. The polyimide film with high thermal conductivity according to claim 3, wherein: the acidified carbon nano tube is prepared by the following steps:

and (3) uniformly dispersing the nitric acid solution and the carbon nano tube, heating to 70 ℃, reacting for 40-45h, washing with deionized water to be neutral, and obtaining the acidified carbon nano tube.

6. The production process of the polyimide film with high thermal conductivity according to claim 1, wherein the production process comprises the following steps: the preparation method comprises the following preparation steps:

a1, dissolving a diamine monomer in an aprotic polar solvent, adding an aromatic dianhydride monomer, and reacting to obtain a polyamic acid solution;

step A2, adding a heat-conducting filler and a dispersing agent into the polyamic acid solution to obtain a film-forming solution;

and step A3, carrying out vacuum defoaming, tape casting film forming, hot cyclization, bidirectional hot drawing treatment and rolling on the film forming solution to obtain the high-thermal-conductivity polyimide film.

7. The production process of the polyimide film with high thermal conductivity according to claim 6, wherein: in the step A1, the aprotic polar solvent is any one of N, N-dimethylformamide and N, N-dimethylacetamide.

8. The production process of the polyimide film with high thermal conductivity according to claim 6, wherein: in the step a1, the aromatic dianhydride monomer is any one of pyromellitic dianhydride, 3 ', 4, 4' -biphenyltetracarboxylic dianhydride, 3 ', 4, 4' -benzophenonetetracarboxylic dianhydride, bisphenol a dianhydride, and bisphenol F dianhydride.

Background

Polyimide (PI) film is a high-temperature resistant insulating material with competitive advantages, and is widely applied to the fields of flexible printed circuit substrates, microelectronic integrated circuits, battery packages, special electrical appliances and the like. In these fields, however, microelectronics are in a high-density and high-speed operation state, so that electronic components and integrated circuits dissipate a large amount of heat. Since polyimide itself is almost a poor thermal conductor, the conventional polyimide film has a thermal conductivity of about 0.16W/(m · K), has poor thermal conductivity, is liable to accumulate heat, affects the stability, life and operational safety of electronic components, and limits the upgrading of the related industries. In order to meet the increasing thermal conduction (heat dissipation) requirements of circuit boards and devices, insulation materials must be considered to have high thermal conductivity, thereby promoting the development and production of highly thermally conductive polyimide films.

Refer to the high thermal conductivity polyimide film containing more than two fillers disclosed in chinese patent CN111630088A, the invention improves the thermal conductivity in the plane direction and the thickness direction of the polyimide film by adding carbon-based or boron-based fillers and metal oxide-based fillers, but when the amount of the thermal conductive fillers is small, the fillers can be uniformly dispersed in the resin, but they cannot form mutual contact and interaction, the thermal conductivity is not greatly improved, and when the amount of the fillers is large, the thermal conductivity of the film is greatly improved, but the comprehensive properties of the film, especially the properties of machinery, tear resistance, etc., are significantly reduced, even the film cannot be cast and stretched, the industrial production cannot be realized, and simultaneously the polyimide film has a deep color and a low transmittance in the visible light band due to the conjugated absorption of the polyimide molecular chain and the effect of the charge transfer complex between the molecule and the molecule, limiting its application in the solar cell field.

Disclosure of Invention

The invention aims to provide a high-thermal-conductivity polyimide film and a production process thereof, and solves the technical problems in the background art.

The purpose of the invention can be realized by the following technical scheme:

a high-thermal-conductivity polyimide film comprises the following raw materials in parts by weight:

35.4 to 50.6 portions of diamine monomer, 200 portions of aprotic polar solvent 120-one, 41.2 to 62.1 portions of aromatic dianhydride monomer, 4.5 to 10.6 portions of heat-conducting filler and 0.5 to 1.1 portions of dispersant;

the high-thermal-conductivity polyimide film is prepared by the following steps:

a1, under the protection of nitrogen, setting the temperature at 15-20 ℃, dissolving a diamine monomer in an aprotic polar solvent, adding an aromatic dianhydride monomer, and stirring for reacting for 40-50min to obtain a polyamic acid solution;

step A2, adding a heat-conducting filler and a dispersing agent into the polyamic acid solution, and performing ultrasonic dispersion uniformly to obtain a film-forming solution;

and step A3, carrying out vacuum defoaming and tape casting on the film forming solution to form a film, then carrying out thermal cyclization and bidirectional thermal drafting treatment, and rolling to obtain the polyimide film with high thermal conductivity.

Further, the aprotic polar solvent in step a1 is any one of N, N-dimethylformamide and N, N-dimethylacetamide.

Further, in the step a1, the aromatic dianhydride monomer is any one of pyromellitic dianhydride, 3 ', 4, 4' -biphenyltetracarboxylic dianhydride, 3 ', 4, 4' -benzophenonetetracarboxylic dianhydride, bisphenol a dianhydride, and bisphenol F dianhydride.

Further, the dispersant is any one of polyethylene glycol and acrylamide.

The diamine monomer is prepared by the following steps:

step S1, adding into a reaction kettle under the protection of argonInto 4 '-chloro-4-nitro- [1, 1' -biphenyl]-2-carbonitrile, K₂HPO₄Cooling N, N-dimethylacetamide to 0 ℃, adding trifluoromethanesulfonyl chloride, performing light source irradiation reaction for 7-8h, adding deionized water, extracting for 2-4 times by using ethyl acetate, combining organic phases, washing by using saturated salt water, drying by using anhydrous magnesium sulfate, and removing a solvent by rotary evaporation to obtain an intermediate 1;

the reaction process is as follows:

step S2, adding the intermediate 1, sodium sulfide nonahydrate and N, N-dimethylacetamide into a three-neck flask, heating to 170 ℃ under the protection of nitrogen, reacting for 24 hours, filtering, washing a filter cake with water, and drying to obtain an intermediate 2;

the reaction process is as follows:

step S3, adding the intermediate 2, glacial acetic acid and potassium permanganate into a three-neck flask, heating to 80 ℃, reacting for 2 hours, filtering, adding deionized water into the filtrate to precipitate a crude product, and recrystallizing with ethanol to obtain an intermediate 3;

the reaction process is as follows:

step S4, adding the intermediate 3, a palladium-carbon catalyst and absolute ethyl alcohol into a three-neck flask, uniformly stirring, introducing nitrogen for protection, adding hydrazine hydrate, heating to 70-75 ℃, reacting for 4-4.5h, filtering, evaporating the filtrate to dryness, and recrystallizing with ethyl alcohol to obtain a diamine monomer.

The reaction process is as follows:

further, in step S1, 4 '-chloro-4-nitro- [1, 1' -biphenyl]-2-carbonitrile, K₂HPO₄The molar ratio of N, N-dimethylacetamide to trifluoromethanesulfonyl chloride is 1: 3: 50: 1.

further, the wavelength of the light source is 280-780nm in step S1.

Further, in the step S2, the dosage ratio of the intermediate 1, the sodium sulfide nonahydrate and the N, N-dimethylacetamide is 0.9-0.92 mol: 0.45-0.46 mol: 410-430 mL.

Further, in the step S3, the dosage ratio of the intermediate 2, glacial acetic acid and potassium permanganate is 0.15-0.18 mol: 523-536 mL: 0.6-0.64 mol.

Further, in the step S4, the dosage ratio of the intermediate 3, the palladium-carbon catalyst, the absolute ethyl alcohol and the hydrazine hydrate is 0.12 to 0.14 mol: 0.4-0.5 g: 510-520 mL: 1.2-1.4 mol.

The heat-conducting filler is prepared by the following steps:

step C1, adding zinc oxide into a sodium hydroxide solution with the mass fraction of 10%, heating to 90 ℃, stirring for reaction for 30-40min, centrifuging, washing the precipitate with acetone, and drying again to obtain hydroxylated zinc oxide;

step C2, adding a nitric acid solution with the mass fraction of 60% and the carbon nano tube into a three-neck flask, uniformly dispersing, heating to 70 ℃, reacting for 40-45h, washing with deionized water to be neutral, and obtaining an acidified carbon nano tube;

and step C3, dispersing the acidified carbon nano tube in DMF (dimethyl formamide), ultrasonically dispersing for 30-40min, adding hydroxylated zinc oxide, heating to 80 ℃, reacting for 20-22h, and washing for 3-4 times by using dichloromethane to obtain the heat-conducting filler.

Further, the amount of the nitric acid solution and the carbon nanotubes used in the step C2 is 100-110 mL: 5-5.5 g.

Further, the using ratio of the acidified carbon nano tube, DMF and hydroxylated zinc oxide in the step C2 is 5-5.5 g: 50-55 mL: 0.5-0.6 g.

The invention has the beneficial effects that:

1) selecting synthetic polyimide monomer, and mixing diamine monomer and aromatic dianhydride monomerThe polyimide film with high heat conductivity and high transparency is prepared through polymerization reaction, the high heat conductivity and the high transparency of the film are mainly contributed by diamine monomer, firstly 4 '-chloro-4-nitro- [1, 1' -biphenyl]-2-carbonitrile with trifluoromethanesulfonyl chloride in K₂HPO₄The intermediate 1 is generated by ring-closing reaction under catalysis and light source irradiation, the intermediate 1 is generated into an intermediate 2 under the action of sodium sulfide nonahydrate, the intermediate 2 is generated into an intermediate 3 under the action of potassium permanganate, and the intermediate 3 is generated into diamine monomer under the action of palladium carbon catalyst. Generally, diamine is used as an electron-rich group, dianhydride is used as an electron-deficient group, and strong charge transfer action occurs between the two groups to form a strong Charge Transfer Complex (CTC), so that the transparency of the film is poor. The diamine monomer contains sulfonyl and trifluoromethyl, the sulfonyl has small flexibility and strong electron-withdrawing effect, so that intermolecular and intramolecular CTC (cell-mediated transport) effects are effectively inhibited, and the bis-trifluoromethyl has a steric hindrance effect, so that the molecular chain conformation is distorted, the molecular chain is loosely stacked, the intermolecular CTC effect caused by the molecular chain stacking can be effectively weakened, the transparency of the film is improved, the high-transparency polyimide film is prepared, and the applicability of the polyimide film in the field of solar cells is expanded.

2) Because the existence of the multi-benzene ring structure in the diamine monomer greatly increases the crystallinity of the polymer, the crystal lattices which are arranged orderly can conduct heat through thermal vibration, phonon heat conduction is realized, the heat conductivity coefficient of the polyimide film is obviously improved, and the heat-conducting filler is added in the polyamic acid, and the zinc oxide and the carbon nano tube are excellent heat-conducting materials, so that the heat-conducting coefficient of the film can be remarkably improved, and the zinc oxide and the carbon nano tube are respectively subjected to surface treatment to obtain hydroxylated zinc oxide and an acidified carbon nano tube, the hydroxylated zinc oxide and the acidified carbon nano tube have hydrogen bond effects, and the bonding force is stronger.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

Preparing a diamine monomer:

step S1, under the protection of argon, adding 4 '-chloro-4-nitro- [1, 1' -biphenyl into a reaction kettle]-2-carbonitrile, K₂HPO₄Cooling N, N-dimethyl acetamide to 0 ℃, adding trifluoromethanesulfonyl chloride, irradiating with a light source for reaction for 7h, adding deionized water, extracting with ethyl acetate for 2 times, combining organic phases, washing with saturated saline, drying with anhydrous magnesium sulfate, and removing the solvent by rotary evaporation to obtain an intermediate 1, wherein 4 '-chloro-4-nitro- [1, 1' -biphenyl is obtained]-2-carbonitrile, K₂HPO₄The molar ratio of N, N-dimethylacetamide to trifluoromethanesulfonyl chloride is 1: 3: 50: 1, the wavelength of a light source is 280 nm;

step S2, adding 0.9mol of intermediate 1, 0.45mol of sodium sulfide nonahydrate and 410mL of N, N-dimethylacetamide into a three-neck flask, heating to 170 ℃ under the protection of nitrogen, reacting for 24 hours, filtering, washing a filter cake with water, and drying to obtain an intermediate 2;

step S3, adding 0.15mol of intermediate 2, 523mL of glacial acetic acid and 0.6mol of potassium permanganate into a three-neck flask, heating to 70 ℃ to react for 2 hours, filtering, adding deionized water into the filtrate to precipitate a crude product, and recrystallizing with ethanol to obtain an intermediate 3;

step S4, adding 0.12mol of intermediate 3, 0.4g of palladium-carbon catalyst and 510mL of absolute ethanol into a three-neck flask, uniformly stirring, introducing nitrogen for protection, adding 1.2mol of hydrazine hydrate, heating to 80 ℃, reacting for 4 hours, filtering, evaporating the filtrate to dryness, and recrystallizing with ethanol to obtain the diamine monomer.

Example 2

Preparing a diamine monomer:

step S1, adding into a reaction kettle under the protection of argonInto 4 '-chloro-4-nitro- [1, 1' -biphenyl]-2-carbonitrile, K₂HPO₄Cooling N, N-dimethyl acetamide to 0 ℃, adding trifluoromethanesulfonyl chloride, irradiating with a light source for reaction for 7h, adding deionized water, extracting with ethyl acetate for 2 times, combining organic phases, washing with saturated saline, drying with anhydrous magnesium sulfate, and removing the solvent by rotary evaporation to obtain an intermediate 1, wherein 4 '-chloro-4-nitro- [1, 1' -biphenyl is obtained]-2-carbonitrile, K₂HPO₄The molar ratio of N, N-dimethylacetamide to trifluoromethanesulfonyl chloride is 1: 3: 50: 1, the wavelength of a light source is 350 nm;

step S2, adding 0.91mol of intermediate 1, 0.45mol of sodium sulfide nonahydrate and 420mL of N, N-dimethylacetamide into a three-neck flask, heating to 170 ℃ under the protection of nitrogen, reacting for 24 hours, filtering, washing a filter cake with water, and drying to obtain an intermediate 2;

step S3, adding 0.16mol of intermediate 2, 529mL of glacial acetic acid and 0.62mol of potassium permanganate into a three-neck flask, heating to 80 ℃, reacting for 2 hours, filtering, adding deionized water into the filtrate to precipitate a crude product, and recrystallizing with ethanol to obtain an intermediate 3;

step S4, adding 0.13mol of intermediate 3, 0.45g of palladium-carbon catalyst and 515mL of absolute ethyl alcohol into a three-neck flask, uniformly stirring, introducing nitrogen for protection, adding 1.3mol of hydrazine hydrate, heating to 72 ℃, reacting for 4 hours, filtering, evaporating the filtrate to dryness, and recrystallizing with ethyl alcohol to obtain the diamine monomer.

Example 3

Preparing a diamine monomer:

step S1, under the protection of argon, adding 4 '-chloro-4-nitro- [1, 1' -biphenyl into a reaction kettle]-2-carbonitrile, K₂HPO₄Cooling N, N-dimethyl acetamide to 0 ℃, adding trifluoromethanesulfonyl chloride, irradiating with a light source for reaction for 8h, adding deionized water, extracting with ethyl acetate for 4 times, combining organic phases, washing with saturated saline, drying with anhydrous magnesium sulfate, and removing the solvent by rotary evaporation to obtain an intermediate 1, wherein 4 '-chloro-4-nitro- [1, 1' -biphenyl is obtained]-2-carbonitrile, K₂HPO₄The molar ratio of N, N-dimethylacetamide to trifluoromethanesulfonyl chloride is 1: 3: 50: 1, the light source wavelength is 780 nm;

step S2, adding 0.92mol of intermediate 1, 0.46mol of sodium sulfide nonahydrate and 430mL of N, N-dimethylacetamide into a three-neck flask, heating to 170 ℃ under the protection of nitrogen, reacting for 24 hours, filtering, washing a filter cake with water, and drying to obtain an intermediate 2;

step S3, adding 0.18mol of intermediate 2, 536mL of glacial acetic acid and 0.64mol of potassium permanganate into a three-neck flask, heating to 80 ℃, reacting for 2 hours, filtering, adding deionized water into the filtrate to precipitate a crude product, and recrystallizing with ethanol to obtain an intermediate 3;

step S4, adding 0.14mol of intermediate 3, 0.5g of palladium-carbon catalyst and 520mL of absolute ethanol into a three-neck flask, uniformly stirring, introducing nitrogen for protection, adding 1.4mol of hydrazine hydrate, heating to 75 ℃, reacting for 4.5h, filtering, evaporating the filtrate to dryness, and recrystallizing with ethanol to obtain a diamine monomer.

Example 4

Preparing a heat-conducting filler:

step C1, adding zinc oxide into a sodium hydroxide solution with the mass fraction of 10%, heating to 90 ℃, stirring for reaction for 30min, centrifuging, washing the precipitate with acetone, and drying again to obtain hydroxylated zinc oxide;

step C2, adding 100mL of nitric acid solution with the mass fraction of 60% and 5g of carbon nano tubes into a three-neck flask, uniformly dispersing, heating to 70 ℃, reacting for 40 hours, washing with deionized water to be neutral, and obtaining acidified carbon nano tubes;

and step C3, dispersing 5g of acidified carbon nano tubes in 50mL of DMF (dimethyl formamide), ultrasonically dispersing for 30min, adding 0.5g of hydroxylated zinc oxide, heating to 80 ℃, reacting for 20h, and washing for 3 times by using dichloromethane to obtain the heat-conducting filler.

Example 5

Preparing a heat-conducting filler:

step C1, adding zinc oxide into a sodium hydroxide solution with the mass fraction of 10%, heating to 90 ℃, stirring for reaction for 35min, centrifuging, washing the precipitate with acetone, and drying again to obtain hydroxylated zinc oxide;

step C2, adding 105mL of nitric acid solution with the mass fraction of 60% and 5.2g of carbon nano tubes into a three-neck flask, uniformly dispersing, heating to 70 ℃, reacting for 43 hours, washing with deionized water to be neutral, and obtaining acidified carbon nano tubes;

and step C3, dispersing 5.3g of acidified carbon nano tubes in 53mL of DMF (dimethyl formamide), ultrasonically dispersing for 35min, adding 0.55g of hydroxylated zinc oxide, heating to 80 ℃, reacting for 21h, and washing for 3 times by using dichloromethane to obtain the heat-conducting filler.

Example 6

Preparing a heat-conducting filler:

step C1, adding zinc oxide into a sodium hydroxide solution with the mass fraction of 10%, heating to 90 ℃, stirring for reaction for 40min, centrifuging, washing the precipitate with acetone, and drying again to obtain hydroxylated zinc oxide;

step C2, adding 110mL of nitric acid solution with the mass fraction of 60% and 5.5g of carbon nano tubes into a three-neck flask, uniformly dispersing, heating to 70 ℃, reacting for 45 hours, washing with deionized water to be neutral, and obtaining acidified carbon nano tubes;

and step C3, dispersing 5.5g of acidified carbon nano tubes in 55mL of DMF (dimethyl formamide), ultrasonically dispersing for 40min, adding 0.6g of hydroxylated zinc oxide, heating to 80 ℃ to react for 22h, and washing for 4 times by using dichloromethane to obtain the heat-conducting filler.

Example 7

A high-thermal-conductivity polyimide film comprises the following raw materials in parts by weight:

35.4 parts of diamine monomer, 120 parts of aprotic polar solvent, 41.2 parts of pyromellitic dianhydride, 4.5 parts of heat-conducting filler and 0.5 part of polyethylene glycol;

the high-strength high-temperature-resistant water supply pipe is prepared by the following steps:

step A1, under the protection of nitrogen, setting the temperature to be 15 ℃, dissolving the diamine monomer prepared in the embodiment 1 into an aprotic polar solvent, adding pyromellitic dianhydride into the solvent, and stirring the mixture to react for 40min to obtain a polyamic acid solution;

step A2, adding the heat-conducting filler and polyethylene glycol prepared in the embodiment 4 into the polyamic acid solution, and obtaining a film-forming solution after uniform ultrasonic dispersion;

and step A3, carrying out vacuum defoaming and tape casting on the film forming solution to form a film, then carrying out thermal cyclization and bidirectional thermal drafting treatment, and rolling to obtain the polyimide film with high thermal conductivity.

Example 8

A high-thermal-conductivity polyimide film comprises the following raw materials in parts by weight:

42.5 parts of diamine monomer, 150 parts of aprotic polar solvent, 50.3 parts of 3,3 ', 4, 4' -biphenyl tetracarboxylic dianhydride, 7.2 parts of heat-conducting filler and 0.7 part of polyethylene glycol;

the high-strength high-temperature-resistant water supply pipe is prepared by the following steps:

step A1, under the protection of nitrogen, setting 18 ℃, dissolving the diamine monomer prepared in the embodiment 2 in an aprotic polar solvent, adding 3,3 ', 4, 4' -biphenyl tetracarboxylic dianhydride into the solvent, and stirring to react for 45min to obtain a polyamic acid solution;

step A2, adding the heat-conducting filler and polyethylene glycol prepared in the example 5 into the polyamic acid solution, and obtaining a film-forming solution after uniform ultrasonic dispersion;

and step A3, carrying out vacuum defoaming and tape casting on the film forming solution to form a film, then carrying out thermal cyclization and bidirectional thermal drafting treatment, and rolling to obtain the polyimide film with high thermal conductivity.

Example 9

A high-thermal-conductivity polyimide film comprises the following raw materials in parts by weight:

50.6 parts of diamine monomer, 200 parts of aprotic polar solvent, 62.1 parts of bisphenol A dianhydride, 10.6 parts of heat-conducting filler and 1.1 parts of acrylamide;

the high-strength high-temperature-resistant water supply pipe is prepared by the following steps:

step A1, under the protection of nitrogen, setting 20 ℃, dissolving the diamine monomer prepared in the embodiment 3 in an aprotic polar solvent, adding bisphenol A dianhydride into the solvent, and stirring for reaction for 50min to obtain a polyamic acid solution;

step a2, adding the heat conductive filler and acrylamide prepared in example 6 into a polyamic acid solution, and obtaining a film forming solution after uniform ultrasonic dispersion;

and step A3, carrying out vacuum defoaming and tape casting on the film forming solution to form a film, then carrying out thermal cyclization and bidirectional thermal drafting treatment, and rolling to obtain the polyimide film with high thermal conductivity.

Comparative example 1

Polyimide film produced by xuchang city yu energy electric insulating material limited company.

Comparative example 2

Comparative example 2 polyimide film was prepared according to example 7, except that no thermally conductive filler was added.

Comparative example 3

Comparative example 3 polyimide film was prepared according to example 8, except that the diamine monomer was replaced with p-phenylenediamine.

The polyimide films obtained in examples 7 to 9 and comparative examples 1 to 3 were subjected to the following performance tests, (1) measurement of light transmittance using a UV spectrophotometer (Konita Minolta, CM-3700d) at 550 nm; (2) thermal conductivity, test method reference ASTM-D696; (3) tensile strength, elongation at break, test methods refer to ASTM-D882; the test results are shown in table 1:

TABLE 1

As can be seen from Table 1, the polyimide films prepared in examples 7 to 9 have superior mechanical properties, higher light transmittance and high thermal conductivity compared with those of comparative examples 1 to 3, and can be used as ideal materials for packaging and heat dissipation of microelectronic devices.

In the description herein, references to the description of "one embodiment," "an example," "a specific example" or the like are intended to mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The foregoing is illustrative and explanatory only and is not intended to be exhaustive or to limit the invention to the precise embodiments described, and various modifications, additions, and substitutions may be made by those skilled in the art without departing from the scope of the invention or exceeding the scope of the claims.