CN108250749A - A kind of preparation method of phenyl silsesquioxane/graphene oxide/polyimides three-phase composite film - Google Patents

Abstract

A method for preparing a phenylsilsesquioxane/graphene oxide/polyimide three-phase composite film, the invention relates to the technical field of insulating materials, in particular to a phenylsilsesquioxane/graphene oxide/ A method for preparing a polyimide three-phase composite film. The invention aims to solve the problem that the existing composite film cannot reduce the dielectric constant and improve its thermal performance and mechanical performance at the same time. Methods: Graphene oxide was prepared by improved Hummers method; phenylsilsesquioxane/graphene oxide/polyimide three-phase composite film was prepared by in-situ polymerization. The invention is applied to the preparation of phenylsilsesquioxane/graphene oxide/polyimide three-phase film.

Description

A kind of phenylsilsesquioxane/graphene oxide/polyimide three-phase composite film Preparation

technical field

The invention relates to the technical field of insulating materials, in particular to a method for preparing a phenylsilsesquioxane/graphene oxide/polyimide three-phase composite film.

Background technique

In recent years, the application of nanoporous materials with low dielectric constant in the microelectronics industry has attracted great attention. Due to good mechanical properties, thermal properties and electrical properties, polyimide has been widely used in dielectric materials and packaging materials in the microelectronics industry. However, with the continuous reduction of the feature size of the chip in the integrated circuit, the parasitic resistance and capacitance of the interconnection will cause the delay of signal transmission, crosstalk and energy loss. A new shackle for the development of multifunctional direction. In order to meet the requirements of high integration of integrated circuits and increase the transmission speed of signals, the high-density signal lines in the package are required to be electrically insulated from each other. Materials with a dielectric constant as low as possible should be selected as insulating materials between metal layers. To ensure that the smallest electrical interaction signals can be normally transmitted in adjacent lines. The dielectric constant of polyimide can be significantly reduced by using the low dielectric constant of air. One method is to prepare low dielectric materials by introducing voids in the matrix, and the other method is to hybridize polyimide In order to introduce a monomer with a hollow structure to reduce the dielectric constant of the material. Nano-sized, uniform and closed pores in materials are beneficial to maintain their electrical and mechanical properties. Therefore, it has become an attractive approach to introduce air gaps in joining structural materials and air in polymers to reduce the dielectric constant of materials.

The preparation of polyimide films with low dielectric constant can be achieved by introducing inorganic components. A class of inorganic-organic components—phenyl oligomeric silsesquioxanes are made of rigid cubic silica [octamer ( R ₈ Si ₈ O ₁₂ )] core and pores with a size of 0.3-0.4nm. It has a special structure between inorganic ceramics and organic cinnamon polymers, so these molecules have hybrid properties. The polymer film based on phenyl silsesquioxane has a low dielectric constant property. During the preparation process, adding a coupling agent to modify phenyl silsesquioxane into polyimide, the prepared organic-inorganic nanocomposite has Lower dielectric constant than virgin polyimide. Another type of inorganic component - graphene oxide, compared with expensive fullerene and carbon nanotubes, graphene oxide is cheap, easy to obtain raw materials, has a good nanosheet structure, large specific surface area, and rich surface functions Groups, etc. make it have better dispersibility in water and organic solvents, and it is easy to form chemical bonds or hydrogen bonds with polymers, so that it has greater potential in improving the properties of polymer composites. Especially in terms of improving mechanical properties and thermal performance, it can be used in the preparation of polymer nanocomposite films. However, there are relatively few studies on the simultaneous introduction of phenylsilsesquioxane and graphene oxide into the polyimide matrix for synergistic modification. Therefore, it is of great significance to prepare phenylsilsesquioxane/graphene oxide/polyimide three-phase composite films with low dielectric constant and good comprehensive properties.

Contents of the invention

The present invention aims to solve the problem that the existing composite film cannot reduce the dielectric constant while improving its thermal performance and mechanical performance, and provides a three-phase composite film of phenylsilsesquioxane/graphene oxide/polyimide The method of film preparation.

The preparation method of a kind of phenylsilsesquioxane/graphene oxide/polyimide three-phase composite film of the present invention is to carry out according to the following steps:

1. Under the condition of ice-water bath, use mixed acid solution to dissolve the expanded graphite, mechanically stir until the expanded graphite is completely dissolved, then add potassium permanganate to it, mechanically stir until the potassium permanganate is completely dissolved, continue stirring for 1-2 hours, and then transfer to Keep warm in a water bath with a temperature of 35°C for 1 to 2 hours, then raise the temperature of the water bath from 35°C to 98°C, and add deionized water to it at a constant rate using a separatory funnel during the heating process until the temperature reaches 98°C. After incubating at 98°C for 1-2 hours, add 30% hydrogen peroxide solution until the solution turns bright yellow; dilute the bright yellow solution, filter the reaction product, and centrifuge the obtained solution repeatedly until the pH value is 7. Dry and grind the obtained product to obtain graphite oxide powder, add the prepared graphite oxide powder into deionized water, and dry it after ultrasonic vibration for 3 hours to obtain graphene oxide; the mixed acid solution is concentrated nitric acid and Concentrated sulfuric acid is obtained by mixing the volume ratio of 1:3; the volume ratio of the quality of the expanded graphite to the mixed acid solution is 1g:(80～120) mL; the mass ratio of the expanded graphite to potassium permanganate is 1:( 5～7); The quality of described expanded graphite and the volume ratio of the deionized water that add in the heating process at a constant speed are 1g:(180～220)mL;

2. Add N,N'-dimethylacetamide solution to the graphene oxide obtained in step 1, and ultrasonically disperse evenly to obtain a dispersion liquid; transfer the dispersion liquid to a constant temperature water bath, in a temperature of 60 ° C and nitrogen Add 4,4'-diaminodiphenyl ether I to the dispersion under protected conditions, reflux and stir for 20-28 hours, then first add phenylsilsesquioxane to it, ultrasonically disperse evenly, and then add silane coupling agent , continue to stir until the mixture is uniform, add 4,4'-diaminodiphenyl ether II and pyromellitic dianhydride again, and stir at room temperature for 12 hours to obtain nano-phenylsilsesquioxane/graphene oxide/polymer Amic acid solution; the mass ratio of graphene oxide to 4,4'-diaminodiphenyl ether I is 2:3; the amount of graphene oxide added is 4,4'-diaminodiphenyl ether II and pyromellitic acid 0.1% to 0.9% of the total mass of dianhydride; the amount of phenylsilsesquioxane added is 1% to 3% of the total mass of 4,4'-diaminodiphenyl ether II and pyromellitic dianhydride; The volume ratio of the mass of 4,4'-diaminodiphenyl ether II to N,N'-dimethylacetamide solution is 1g:12mL; 4,4'-diaminodiphenyl ether II and pyromellitic acid The molar ratio of dianhydride is 99:100;

3. Transfer the nano-phenyl silsesquioxane/graphene oxide/polyamic acid solution obtained in step 2 to a constant temperature water bath with a temperature of 50°C, heat and degrade it for 30 minutes, then carry out film coating treatment, and then adopt a gradient heating method The POSS/ODA-GO/PI composite film was prepared by heating to 300°C for thermal imidization and cooling to room temperature.

The beneficial effects of the present invention are:

1. The present invention is mainly applied to the use of electronic packaging materials in the field of microelectronics. The in-situ polymerization method is used to prepare phenylsilsesquioxane/graphene oxide/polyimide three-phase composite films, and the oxide film is prepared by the improved Hummers method. Graphene. According to the characterization results of scanning electron microscopy and atomic force microscopy, the graphene oxide sheet is relatively thin, with a single layer thickness of 0.78nm.

2. The present invention prepares a kind of dielectric and thermal properties by loading phenyl silsesquioxane with rigid hollow core on the graphene oxide sheet and introducing it into the polyimide matrix by in-situ polymerization. The three-phase composite material with good mechanical and mechanical properties can be used in circuit boards and packaging materials in the field of microelectronics.

3. The advantage of the present invention is that the phenyl silsesquioxane used is at the nanoscale, which can give full play to the reinforcing effect of nanoparticles on the material. After the oxane is loaded, it can be uniformly dispersed in the polyimide matrix, and the three-phase composite material of phenylsilsesquioxane/graphene oxide/polyimide has excellent dielectric properties, thermal properties and mechanical properties. and other characteristics; its dielectric constant is 2.5-2.9 (1MHz), the 5wt% thermal decomposition temperature of the material is 446-564°C, and the tensile strength is 81.8-93.5MPa.

4. The nanoscale phenyl silsesquioxane of the present invention is a new type of organic-inorganic filler. Its obvious feature is that it has a hollow core, and the entire molecule is at the nanoscale, and the nanoscale phenyl silsesquioxane The introduction of siloxane will introduce more air into the matrix, thereby significantly reducing its dielectric constant, and the rigid core of phenylsilsesquioxane itself endows it with good mechanical properties, and the higher thermal decomposition temperature also It has good thermal properties, and after compounding with polyimide, it can meet the requirements of high-speed integrated circuits for dielectric materials.

5. The graphene oxide of the present invention is one of the important derivatives of graphene. Graphene oxide is improving polymerization due to its extremely high specific surface area, special two-dimensional planar structure of graphite, and low processing cost. It has great application prospects in terms of its performance. The basic structure of graphene oxide is similar to that of graphene, so graphene oxide has good physical properties. However, it is different from graphene in chemical structure, so it has the potential for further functionalization. Abundant oxygen-containing groups, such as hydroxyl, carboxyl, epoxy and carbonyl groups, are connected to the surface of the graphene oxide sheet and its surroundings. These oxygen-containing groups on the surface of graphene oxide make it a good medium Electrical properties, multiple chemical functionalization base points, better compatibility, and the ability of graphene oxide to react with polymers to form chemical bonds enhance the dispersion of graphene oxide in polymer matrices. Doping graphene oxide into the polymer is beneficial to obtain a composite material with good thermal stability and excellent dielectric properties, so graphene oxide plays a huge role in the preparation of low-dielectric composite material substrates with excellent comprehensive properties. effect.

6. The present invention adopts nanoscale phenyl silsesquioxane, through the silane coupling agent and the graphene oxide load prepared by the improved Hummers hair, the phenyl silsesquioxane/graphene oxide composite powder and Polyamic acid composite, play the role of phenylsilsesquioxane and graphene oxide in improving the dielectric properties, thermal properties and mechanical properties of materials, and prepare benzene with low dielectric constant, good thermal and mechanical properties after subsequent treatment. Silsesquioxane/graphene oxide/polyimide three-phase composites.

Description of drawings

Fig. 1 is the graphene oxide atomic force microscope figure that embodiment one obtains;

Fig. 2 is the transmission electron microscope figure of the graphene oxide that embodiment one obtains;

Fig. 3 is the transmission electron microscope picture of the 4,4'-diaminodiphenyl ether-graphene oxide that embodiment one obtains;

Fig. 4 is the transmission electron microscope picture of nanometer phenyl silsesquioxane in embodiment one;

Fig. 5 is the powder transmission electron microscope picture of the nano-phenyl silsesquioxane supported graphene oxide that embodiment one obtains;

6 is a scanning electron microscope image of the phenylsilsesquioxane/graphene oxide/polyimide composite material obtained in Example 1.

Detailed ways

Specific embodiment one: the preparation method of a kind of phenylsilsesquioxane/graphene oxide/polyimide three-phase composite film of this embodiment is to carry out according to the following steps:

1. Under the condition of ice-water bath, use mixed acid solution to dissolve the expanded graphite, mechanically stir until the expanded graphite is completely dissolved, then add potassium permanganate to it, mechanically stir until the potassium permanganate is completely dissolved, continue stirring for 1-2 hours, and then transfer to Keep warm in a water bath with a temperature of 35°C for 1 to 2 hours, then raise the temperature of the water bath from 35°C to 98°C, and add deionized water to it at a constant rate using a separatory funnel during the heating process until the temperature reaches 98°C. After incubating at 98°C for 1-2 hours, add 30% hydrogen peroxide solution until the solution turns bright yellow; dilute the bright yellow solution, filter the reaction product, and centrifuge the obtained solution repeatedly until the pH value is 7. Dry and grind the obtained product to obtain graphite oxide powder, add the prepared graphite oxide powder into deionized water, and dry it after ultrasonic vibration for 3 hours to obtain graphene oxide; the mixed acid solution is concentrated nitric acid and Concentrated sulfuric acid is obtained by mixing the volume ratio of 1:3; the volume ratio of the quality of the expanded graphite to the mixed acid solution is 1g:(80～120) mL; the mass ratio of the expanded graphite to potassium permanganate is 1:( 5～7); The quality of described expanded graphite and the volume ratio of the deionized water that add in the heating process at a constant speed are 1g:(180～220)mL;

2. Add N,N'-dimethylacetamide solution to the graphene oxide obtained in step 1, and ultrasonically disperse evenly to obtain a dispersion liquid; transfer the dispersion liquid to a constant temperature water bath, in a temperature of 60 ° C and nitrogen Add 4,4'-diaminodiphenyl ether I to the dispersion under protected conditions, reflux and stir for 20-28 hours, then first add phenylsilsesquioxane to it, ultrasonically disperse evenly, and then add silane coupling agent , continue to stir until the mixture is uniform, add 4,4'-diaminodiphenyl ether II and pyromellitic dianhydride again, and stir at room temperature for 12 hours to obtain nano-phenylsilsesquioxane/graphene oxide/polymer Amic acid solution; the mass ratio of graphene oxide to 4,4'-diaminodiphenyl ether I is 2:3; the amount of graphene oxide added is 4,4'-diaminodiphenyl ether II and pyromellitic acid 0.1% to 0.9% of the total mass of dianhydride; the amount of phenylsilsesquioxane added is 1% to 3% of the total mass of 4,4'-diaminodiphenyl ether II and pyromellitic dianhydride; The volume ratio of the mass of 4,4'-diaminodiphenyl ether II to N,N'-dimethylacetamide solution is 1g:12mL; 4,4'-diaminodiphenyl ether II and pyromellitic acid The molar ratio of dianhydride is 99:100;

3. Transfer the nano-phenyl silsesquioxane/graphene oxide/polyamic acid solution obtained in step 2 to a constant temperature water bath with a temperature of 50°C, heat and degrade it for 30 minutes, then carry out film coating treatment, and then adopt a gradient heating method The POSS/ODA-GO/PI composite film was prepared by heating to 300°C for thermal imidization and cooling to room temperature.

In this embodiment, phenylsilsesquioxane and graphene oxide are evenly distributed in the polyimide matrix by in-situ polymerization. After graphene oxide is modified by 4,4'-diaminodiphenyl ether, graphite oxide The further increase of the interlayer spacing of the olefin sheet is conducive to the formation of chemical bonds between the graphene oxide and the polyimide matrix, which is conducive to the uniform distribution of the graphene oxide during the composite process, and the phenylsilsesquioxane loaded on the graphene oxide The surface, along with the uniform distribution of graphene oxide, is also uniformly distributed in the polyimide matrix, which is conducive to obtaining a uniformly distributed and stable three-phase composite film. The phenylsilsesquioxane/graphene oxide/polyimide three-phase composite film contributes to the reduction of the dielectric constant of the polyimide and maintains its thermal and mechanical properties. The phenylsilsesquioxane/graphene oxide/polyimide three-phase composite film can change the performance of the polyimide composite material by adjusting the addition of phenylsilsesquioxane and graphene oxide.

After adding 4,4'-diaminodiphenyl ether II and pyromellitic dianhydride in step 2 of this embodiment, when the molar ratio of the two reaches the same amount, the viscosity of the system increases sharply, and there is an obvious rod climbing phenomenon.

Embodiment 2: The difference between this embodiment and Embodiment 1 is that the volume ratio of the mass of expanded graphite described in step 1 to the mixed acid solution is 1g:100mL. Others are the same as in the first embodiment.

Specific embodiment three: the difference between this embodiment and specific embodiment one or two is: the mass ratio of expanded graphite and potassium permanganate described in step one is 1:6. Others are the same as in the first or second embodiment.

Embodiment 4: This embodiment differs from Embodiments 1 to 3 in that: the potassium permanganate described in step 1 is added in the following way: potassium permanganate is added in 6 times on average, with an interval of 10 minutes each time. Others are the same as the specific embodiments 1 to 3.

Embodiment 5: This embodiment differs from Embodiment 1 to Embodiment 4 in that the volume ratio of the quality of expanded graphite described in step 1 to the deionized water added at a constant speed during the heating process is 1g:200mL. Others are the same as one of the specific embodiments 1 to 4.

Embodiment 6: The difference between this embodiment and one of Embodiments 1 to 5 is that the silane coupling agent described in step 2 is 3-aminopropyltrimethoxysilane, and every time 4,4'-diaminodi 1% phenylsilsesquioxane based on the total mass of phenylene ether II and pyromellitic dianhydride, add 5 drops of silane coupling agent. Others are the same as one of the specific embodiments 1 to 5.

The silane coupling agent is titrated using a standard burette.

Embodiment 7: The difference between this embodiment and one of Embodiments 1 to 6 is that the method of adding pyromellitic dianhydride described in step 2 is as follows: adding pyromellitic dianhydride on average in 6 times, Each interval is 15 minutes. Others are the same as one of the specific embodiments 1 to 6.

Embodiment 8: The difference between this embodiment and one of Embodiments 1 to 7 is that the amount of graphene oxide added in Step 2 is 4,4'-diaminodiphenyl ether II and pyromellitic dianhydride 0.1% to 0.9% of the total mass. Others are the same as one of the specific embodiments 1 to 7.

Embodiment 9: The difference between this embodiment and one of Embodiments 1 to 8 is that the gradient temperature increase in step 3 is to raise the temperature from 50°C to 80°C, and keep it at 80°C for 0.5h , then raise the temperature from 80°C to 120°C, and keep it at 120°C for 0.5h, then raise the temperature from 120°C to 150°C, keep it at 150°C for 0.5h, and then The temperature was raised from 150°C to 180°C, and kept at 180°C for 0.5h, then raised from 180°C to 200°C, and kept at 200°C for 0.5h. Then the temperature was raised from 200°C to 250°C, and kept at 250°C for 0.5h. Then the temperature was raised from 250°C to 300°C, and kept at 300°C for 0.5h. Others are the same as one of the specific embodiments 1 to 8.

Verify the beneficial effects of the present invention through the following examples:

Embodiment one: a kind of preparation method of phenylsilsesquioxane/graphene oxide/polyimide three-phase composite film is to carry out according to the following steps:

1. Under the condition of ice-water bath, use mixed acid solution to dissolve 1g of expanded graphite, mechanically stir until the expanded graphite is completely dissolved, then add 6g of potassium permanganate to it, mechanically stir until the potassium permanganate is completely dissolved, continue stirring for 1h, and then transfer to Keep warm in a water bath at a temperature of 35°C for 2 hours, then raise the temperature of the water bath from 35°C to 98°C, and add 200 mL of deionized water to it at a constant rate using a separatory funnel during the heating process until the temperature reaches 98°C. After incubating at 98°C for 1 hour, add a 30% hydrogen peroxide solution until the solution turns bright yellow; dilute the bright yellow solution, filter the reaction product, and centrifuge the obtained solution repeatedly until the pH value is 7. The obtained product was dried and ground to obtain graphite oxide powder, and the prepared graphite oxide powder was added to deionized water, ultrasonically oscillated for 3 hours and then dried to obtain graphene oxide; the mixed acid solution was 25mL concentrated nitric acid and 75mL concentrated Obtained by mixing sulfuric acid; the addition method of the potassium permanganate is as follows: the potassium permanganate is added in 6 times on average, with an interval of 10 minutes each time;

2. Add N,N'-dimethylacetamide solution to the graphene oxide obtained in step 1, and ultrasonically disperse evenly to obtain a dispersion liquid; transfer the dispersion liquid to a constant temperature water bath, in a temperature of 60 ° C and nitrogen Add 4,4'-diaminodiphenyl ether I to the dispersion under protected conditions, reflux and stir for 20-28 hours, then first add phenylsilsesquioxane to it, ultrasonically disperse evenly, and then add silane coupling agent , continue to stir until the mixture is uniform, add 4,4'-diaminodiphenyl ether II and pyromellitic dianhydride again, and stir at room temperature for 12 hours to obtain nano-phenylsilsesquioxane/graphene oxide/polymer Amic acid solution; the mass ratio of graphene oxide to 4,4'-diaminodiphenyl ether II is 2:3; the amount of graphene oxide added is 4,4'-diaminodiphenyl ether II and pyromellitic acid 0.1% to 0.9% of the total mass of dianhydride; the amount of phenylsilsesquioxane added is 1% to 3% of the total mass of 4,4'-diaminodiphenyl ether II and pyromellitic dianhydride; The volume ratio of the mass of 4,4'-diaminodiphenyl ether II to N,N'-dimethylacetamide solution is 1g:12mL; 4,4'-diaminodiphenyl ether II and pyromellitic acid The molar ratio of the dianhydride is 99:100; the addition method of the pyromellitic dianhydride is as follows: the pyromellitic dianhydride is added in 6 times on average, with an interval of 15 minutes each time;

3. Transfer the nano-phenyl silsesquioxane/graphene oxide/polyamic acid solution obtained in step 2 to a constant temperature water bath with a temperature of 50°C, heat and degrade it for 30 minutes, then carry out film coating treatment, and then adopt a gradient heating method heated to 300°C for thermal imidization, and cooled to room temperature to obtain a POSS/ODA-GO/PI composite film; the gradient temperature was raised from 50°C to 80°C, and the Keep it under the condition for 0.5h, then raise the temperature from 80°C to 120°C, and keep it at 120°C for 0.5h, then raise the temperature from 120°C to 150°C, and keep it at 150°C 0.5h, then raise the temperature from 150°C to 180°C, keep at 180°C for 0.5h, then raise the temperature from 180°C to 200°C, and keep at 200°C for 0.5h. Then the temperature was raised from 200°C to 250°C, and kept at 250°C for 0.5h. Then the temperature was raised from 250°C to 300°C, and kept at 300°C for 0.5h.

Fig. 1 is the graphene oxide atomic force microscope figure that embodiment one obtains; Fig. 2 is the transmission electron microscope figure of the graphene oxide that embodiment one obtains; Fig. 3 is the 4,4'-diaminodiphenyl ether that embodiment one obtains- The transmission electron microscope figure of graphene oxide; Fig. 4 is the transmission electron microscope figure of nanometer phenylsilsesquioxane in embodiment one; Fig. 5 is the powder of nanometer phenylsilsesquioxane supported graphene oxide that embodiment one obtains Bulk transmission electron micrograph; Figure 6 is a scanning electron micrograph of the phenylsilsesquioxane/graphene oxide/polyimide composite material obtained in Example 1.

The thickness between the two points in Figure 1 is measured to be 0.78nm, indicating that the graphene oxide sheet prepared by the present invention is relatively thin, and the single layer reaches the nanometer level.

It can be seen from FIG. 2 that the sheet edge length of the graphene oxide prepared by the present invention is between 500 nm and 1 μm.

It can be seen from Figure 3 that the surface wrinkles of graphene oxide sheets modified by 4,4'-diaminodiphenyl ether increase, indicating that the modification is successful and the distance between sheets increases due to modification.

From Fig. 4, it can be seen that the surface size of the phenylsilsesquioxane filler used in the present invention is a cube structure with a side length between 10 and 20 nm, indicating that the phenylsilsesquioxane used in the present invention is in nanometer size and can Give full play to the reinforcing effect of nano fillers on materials.

It can be seen from Figure 5 that phenylsilsesquioxane particles are supported on the surface and surroundings of the graphene oxide sheet, indicating that with graphene oxide uniformly distributed in the polyimide matrix, phenylsilsesquioxane will also Evenly distributed in the polyimide matrix.

It can be seen from Figure 6 that there are clearly visible graphene oxide sheets on the cross section of the material, and evenly distributed phenylsilsesquioxane particles are clearly visible, indicating that the graphene oxide sheets and phenylsilsesquioxane are evenly coated. Covering the inside of the polyimide matrix can give full play to the reinforcing effect of the filler on the matrix material.

Claims (9)

1. A preparation method of phenylsilsesquioxane/graphene oxide/polyimide three-phase composite film, characterized in that phenylsilsesquioxane/graphene oxide/polyimide three-phase composite The preparation method of film is to carry out according to the following steps: 1. Under the condition of ice-water bath, use mixed acid solution to dissolve the expanded graphite, mechanically stir until the expanded graphite is completely dissolved, then add potassium permanganate to it, mechanically stir until the potassium permanganate is completely dissolved, continue stirring for 1-2 hours, and then transfer to Keep warm in a water bath with a temperature of 35°C for 1 to 2 hours, then raise the temperature of the water bath from 35°C to 98°C, and add deionized water to it at a constant rate using a separatory funnel during the heating process until the temperature reaches 98°C. After incubating at 98°C for 1-2 hours, add 30% hydrogen peroxide solution until the solution turns bright yellow; dilute the bright yellow solution, filter the reaction product, and centrifuge the obtained solution repeatedly until the pH value is 7. Dry and grind the obtained product to obtain graphite oxide powder, add the prepared graphite oxide powder into deionized water, and dry it after ultrasonic vibration for 3 hours to obtain graphene oxide; the mixed acid solution is concentrated nitric acid and Concentrated sulfuric acid is obtained by mixing the volume ratio of 1:3; the volume ratio of the quality of the expanded graphite to the mixed acid solution is 1g:(80～120) mL; the mass ratio of the expanded graphite to potassium permanganate is 1:( 5～7); The quality of described expanded graphite and the volume ratio of the deionized water that add in the heating process at a constant speed are 1g:(180～220)mL; 2. Add N,N'-dimethylacetamide solution to the graphene oxide obtained in step 1, and ultrasonically disperse evenly to obtain a dispersion liquid; transfer the dispersion liquid to a constant temperature water bath, in a temperature of 60 ° C and nitrogen Add 4,4'-diaminodiphenyl ether I to the dispersion under protected conditions, reflux and stir for 20-28 hours, then first add phenylsilsesquioxane to it, ultrasonically disperse evenly, and then add silane coupling agent , continue to stir until the mixture is uniform, add 4,4'-diaminodiphenyl ether II and pyromellitic dianhydride again, and stir at room temperature for 12 hours to obtain nano-phenylsilsesquioxane/graphene oxide/polymer Amic acid solution; the mass ratio of graphene oxide to 4,4'-diaminodiphenyl ether I is 2:3; the amount of graphene oxide added is 4,4'-diaminodiphenyl ether II and pyromellitic acid 0.1% to 0.9% of the total mass of dianhydride; the amount of phenylsilsesquioxane added is 1% to 3% of the total mass of 4,4'-diaminodiphenyl ether II and pyromellitic dianhydride; The volume ratio of the mass of 4,4'-diaminodiphenyl ether II to N,N'-dimethylacetamide solution is 1g:12mL; 4,4'-diaminodiphenyl ether II and pyromellitic acid The molar ratio of dianhydride is 99:100; 3. Transfer the nano-phenyl silsesquioxane/graphene oxide/polyamic acid solution obtained in step 2 to a constant temperature water bath with a temperature of 50°C, heat and degrade it for 30 minutes, then carry out film coating treatment, and then adopt a gradient heating method The POSS/ODA-GO/PI composite film was prepared by heating to 300°C for thermal imidization and cooling to room temperature. 2. the preparation method of a kind of phenylsilsesquioxane/graphene oxide/polyimide three-phase composite film according to claim 1 is characterized in that the quality of expanded graphite described in step 1 and mixed acid solution The volume ratio is 1g:100mL. 3. the preparation method of a kind of phenylsilsesquioxane/graphene oxide/polyimide three-phase composite film according to claim 1 is characterized in that described expanded graphite and potassium permanganate in step one The mass ratio is 1:6. 4. the preparation method of a kind of phenylsilsesquioxane/graphene oxide/polyimide three-phase composite film according to claim 1 is characterized in that the addition mode of potassium permanganate described in step one As follows: Potassium permanganate is added in 6 times on average, with an interval of 10 minutes between each time. 5. the preparation method of a kind of phenylsilsesquioxane/graphene oxide/polyimide three-phase composite film according to claim 1 is characterized in that the quality and heating process of expanded graphite described in step one The volume ratio of deionized water added at a constant speed was 1g:200mL. 6. the preparation method of a kind of phenylsilsesquioxane/graphene oxide/polyimide three-phase composite film according to claim 1 is characterized in that the silane coupling agent described in step 2 is 3- For aminopropyltrimethoxysilane, add 5 drops of silane coupling agent for every 1% of phenylsilsesquioxane based on the total mass of 4,4'-diaminodiphenyl ether II and pyromellitic dianhydride. 7. the preparation method of a kind of phenylsilsesquioxane/graphene oxide/polyimide three-phase composite film according to claim 1 is characterized in that the pyromellitic dianhydride described in step 2 The adding method is as follows: add pyromellitic dianhydride in 6 times on average, with an interval of 15 minutes between each time. 8. the preparation method of a kind of phenylsilsesquioxane/graphene oxide/polyimide three-phase composite film according to claim 1 is characterized in that the addition of graphene oxide described in step 2 is 0.5% of the total mass of 4,4'-diaminodiphenyl ether II and pyromellitic dianhydride. 9. the preparation method of a kind of phenylsilsesquioxane/graphene oxide/polyimide three-phase composite film according to claim 1, it is characterized in that described in step 3 gradient heating is that temperature is from 50 Raise the temperature to 80°C and keep it at 80°C for 0.5h, then raise the temperature from 80°C to 120°C and keep it at 120°C for 0.5h, then raise the temperature from 120°C to 150°C, keep at 150°C for 0.5h, then raise the temperature from 150°C to 180°C, keep at 180°C for 0.5h, then raise the temperature from 180°C to 200°C, Keep at 200°C for 0.5h. Then the temperature was raised from 200°C to 250°C, and kept at 250°C for 0.5h. Then the temperature was raised from 250°C to 300°C, and kept at 300°C for 0.5h.