WO2022012076A1

WO2022012076A1 - Low-dielectric polyimide composite thin film material and preparation method therefor

Info

Publication number: WO2022012076A1
Application number: PCT/CN2021/082189
Authority: WO
Inventors: 闵永刚; 朋小康; 廖松义; 黄兴文; 张诗洋; 刘荣涛; 赵晨; 刘屹东
Original assignee: 广东工业大学; 东莞华南设计创新院
Priority date: 2020-07-14
Filing date: 2021-03-22
Publication date: 2022-01-20
Also published as: CN111995866A; CN111995866B

Abstract

A low-dielectric polyimide composite thin film material and a preparation method therefor. The method comprises the following steps: reacting diamine with dianhydride to prepare a polyamide acid solution; preparing graphene quantum dots by using a citric acid hydrothermal method, and performing amidation reaction on the graphene quantum dots and diaminopyridine to obtain aminopyridine functionalized graphene quantum dots; and mixing the polyamide acid solution and the functionalized graphene quantum dots at room temperature, performing spin coating, and performing gradient imidization treatment to obtain a low-dielectric polyimide composite thin film material. The functionalized graphene quantum dots are uniformly dispersed in a polyimide matrix to form a thin film material having uniform and controllable thickness.

Description

A kind of low-dielectric polyimide composite film material and preparation method thereof

technical field

The invention relates to the field of photosensitive polyimide materials, in particular to a low-dielectric polyimide composite film material and a preparation method thereof.

Background technique

As an engineering material with high and low temperature resistance, high strength, high modulus, low water absorption, radiation resistance and excellent insulation, polyimide has been widely used in the fields of microelectronics, information, atomic energy industry and aerospace. Applications. With the development of society and science and technology, especially the rapid development of aerospace, information energy, electrical and electronic industry and microelectronics industry in recent years, higher and updated requirements have been put forward for materials. Pure polyimide materials have special requirements. The field of functional materials, such as the field of optical, electrical and magnetic materials, is increasingly showing its deficiencies. With the gradual spread of 5G construction, the dielectric properties of traditional polyimide materials can no longer meet the high-frequency and high-speed operation requirements of 5G. Doping inorganic fillers can effectively increase the free volume, reduce the molar polarizability, and then reduce the dielectric constant. However, the size of inorganic fillers is generally large, and the effect of reducing the dielectric constant of polyimide materials is not ideal.

SUMMARY OF THE INVENTION

In order to solve the technical problem that the existing polyimide is unfavorable to use, the present invention provides a low-dielectric polyimide composite film material and a preparation method thereof.

The invention provides a method for preparing a low-dielectric polyimide composite film material. adding in batches; reacting for a preset time to obtain a polyamic acid solution; using citric acid hydrothermal method to prepare graphene quantum dots, and then performing amidation reaction with diaminopyridine and graphene quantum dots to obtain aminopyridine-functionalized graphite Graphene quantum dots; the polyamic acid solution and the functionalized graphene quantum dots are stirred at room temperature to obtain a mixed solution; the mixed solution is spin-coated to obtain a polyamic acid composite film, which is then subjected to gradient imidization treatment within a certain temperature range. A low-dielectric polyimide composite film material was obtained.

Further, the molar mass ratio of the diamine monomer and the dibasic anhydride monomer is 1: (1-1.2); the sum of the mass of the diamine monomer and the dibasic anhydride monomer and the organic The mass ratio of the solvent is (0.5-2.5):10.

Further, the organic solvent is one or more of N,N-dimethylacetamide, N,N-dimethylformamide and N-methylpyrrolidone.

Further, the described dibasic anhydride monomer is one or more of 6FDA, 6FXDA, PFPDA, 3FDA, 3FXDA, 3FX3FXDA, and its molecular structural formula is as follows:

Further, the temperature range of the graphene quantum dots prepared by the citric acid hydrothermal method is 160-240°C.

Further, the diamine monomer is more than one of TFMOB, 3,3'-6FDAm, 3FDAm, TFMB, 4,4'-6FDAm or BDAF, and its molecular structural formula is as follows:

Further, the diaminopyridine is one or more of 2,3-diaminopyridine, 2,6-diaminopyridine, 2,5-diaminopyridine and 3,4-diaminopyridine.

Further, the gradient imidization temperature range of the polyamic acid composite film is 100-400°C.

On the other hand, the present invention also provides a low-dielectric polyimide composite film material, and the low-dielectric polyimide composite film material is prepared by the preparation method.

The beneficial effects of the present invention are as follows: the present invention adopts diaminopyridine to functionalize the graphene quantum dots, and the graphene quantum dots can be uniformly dispersed in the matrix by the salt-forming effect between the amino group and the carboxyl group in the polyamic acid. The purpose is to effectively reduce the dielectric constant of polyimide. In addition, the composite film material prepared by introducing pyridine-functionalized graphene quantum dots into polyimide has the characteristics of low dielectric constant, low imidization temperature, and energy saving. The preparation method of the invention is simple, the used graphene quantum dots reach nanometer level, the specific surface area is large, and after modification, they can be uniformly dispersed in the polyimide matrix to form a thin film material with uniform and controllable thickness.

detailed description

The following describes in detail the embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals refer to the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary, and are intended to explain the present invention and should not be construed as limiting the present invention.

In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", " Rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", etc. The relationship is based on the orientation or positional relationship shown in the drawings, only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore It should not be construed as a limitation of the present invention.

In addition, the terms "first" and "second" are only used for descriptive purposes, and should not be construed as indicating or implying relative importance or implying the number of indicated technical features. Thus, a feature defined as "first" or "second" may expressly or implicitly include one or more of that feature. In the description of the present invention, "plurality" means two or more, unless otherwise expressly and specifically defined.

In the present invention, unless otherwise expressly specified and limited, the terms "installed", "connected", "connected", "fixed" and other terms should be understood in a broad sense, for example, it may be a fixed connection or a detachable connection , or integrally connected; it can be a mechanical connection or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or the internal communication between the two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

In the present invention, unless otherwise expressly specified and limited, a first feature "on" or "under" a second feature may include the first and second features in direct contact, or may include the first and second features Not directly but through additional features between them. Also, the first feature being "above", "over" and "above" the second feature includes the first feature being directly above and obliquely above the second feature, or simply means that the first feature is level higher than the second feature. The first feature is "below", "below" and "below" the second feature includes the first feature is directly below and diagonally below the second feature, or simply means that the first feature has a lower level than the second feature.

The present invention will be further described in detail below through specific embodiments in conjunction with the accompanying drawings.

Specifically, the amidation reaction of described diaminopyridine and graphene quantum dots comprises the following steps:

The graphene quantum dots are dispersed in a mixed solvent of thionyl chloride and toluene, refluxed for 12 hours in a temperature range of 60 to 100° C., washed with a tetrahydrofuran solution, and dried to obtain acyl chloride graphene quantum dots;

Graphene acyl chloride quantum dots are dispersed in tetrahydrofuran solution, add diaminopyridine, stir at room temperature, pass nitrogen or argon flow, react for 6 h, and dialyze the product and freeze-dry to obtain aminopyridine functionalized graphene quantum dots.

In the present invention, the graphene quantum dots are functionalized and modified by using diaminopyridine, and the salt-forming effect between the amino group and the carboxyl group in the polyamic acid can be used to make the graphene quantum dots uniformly disperse in the matrix, and the polyamide can be effectively reduced. Dielectric constant of imine. In addition, the composite film material prepared by introducing pyridine-functionalized graphene quantum dots into polyimide has the characteristics of low dielectric constant, low imidization temperature, and energy saving. The preparation method of the invention is simple, the used graphene quantum dots reach nanometer level, the specific surface area is large, and after modification, they can be uniformly dispersed in the polyimide matrix to form a thin film material with uniform and controllable thickness.

The application of the low-dielectric polyimide composite film material in the fields of integrated circuits, 5G communication antenna materials or flexible copper clad laminates. The film has the characteristics of good heat resistance, low dielectric constant, low dielectric loss, low imidization temperature, and energy saving.

In an optional embodiment, the molar mass ratio of the diamine monomer and the dibasic anhydride monomer is 1: (1-1.2); the ratio of the diamine monomer and the dibasic anhydride monomer is The ratio of the sum of the mass to the mass of the organic solvent is (0.5-2.5):10.

In an optional embodiment, the organic solvent is one or more of N,N-dimethylacetamide, N,N-dimethylformamide and N-methylpyrrolidone.

In an optional embodiment, the described dibasic anhydride monomer is one or more of 6FDA, 6FXDA, PFPDA, 3FDA, 3FXDA, 3FX3FXDA, and its molecular structural formula is as follows:

In an optional embodiment, the temperature range of the graphene quantum dots prepared by the citric acid hydrothermal method is 160-240°C.

In an optional embodiment, the diamine monomer is one or more of TFMOB, 3,3'-6FDAm, 3FDAm, TFMB, 4,4'-6FDAm or BDAF, and its molecular structure is as follows :

In an optional embodiment, the diaminopyridine is 2,3-diaminopyridine, one of 2,6-diaminopyridine, 2,5-diaminopyridine and 3,4-diaminopyridine or more.

In an optional embodiment, the gradient imidization temperature range of the polyamic acid composite film is 100-400°C.

Specific examples are as follows:

Example 1

1. Dissolve 10mmol of 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl (TFMB) and 10mmol of hexafluorodianhydride (6FDA) in 40mL of N,N-dimethylethyl acetate successively. In the amide solvent (the dibasic anhydride monomers are added in batches), the reaction is stirred at room temperature in a nitrogen atmosphere to obtain a polyamic acid (PAA) solution;

2. Dissolve 2.0 g of citric acid in 10 mL of deionized water, stir to form a uniform solution, transfer the solution to a lined polytetrafluoroethylene hydrothermal reactor, and react at 200 ° C for 8 hours to obtain a brown solution, and then the brown The solution was dialyzed with a dialysis bag (molecular weight cut-off Da=500) for 3 days to obtain a graphene quantum dot solution, and then freeze-dried for 3 days to obtain graphene quantum dot powder (GQDs);

3. First disperse 1g GQDs in 100mL thionyl chloride and 30mL benzene solution, reflux at 80°C for 12h, wash the reflux product with tetrahydrofuran, and dry for 12h to obtain acid chloride GQDs powder; then disperse 100mg GQDs powder in tetrahydrofuran In the solution, 20mg 2,3-diaminopyridine was added, and under stirring at room temperature, a nitrogen stream was introduced to react for 6h, the product was dialyzed with a dialysis bag (molecular weight cutoff Da=500) for 3 days, and the dialysis product was freeze-dried for 3 days to obtain Aminopyridine functionalized graphene quantum dots (FGQDs-1);

4. Add 1wt% of functionalized graphene quantum dots (FGQDs-1) to the PAA solution, stir to obtain a mixed solution, spin-coat the mixed solution to obtain a polyamic acid composite film, and then undergo 100 ℃, 200 ℃, After gradient imidization at 300°C, 350°C, and 400°C, a low-dielectric polyimide/graphene quantum dot composite film was obtained.

The average thickness of the obtained polyimide composite film is 15μm, the dielectric constant is 2.67@1MHz, the water absorption rate is 0.68%, and the thermal expansion coefficient is 27.6ppm/℃, which has considerable application prospects in the field of integrated circuits and 5G communications.

Example 2

1. 10mmol 2,2-bis(4-aminophenyl) hexafluoropropane (4,4'-6FDAm) and 10mmol 1,3-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride ( PFPDA) was successively dissolved in 40 mL of N,N-dimethylformamide solvent (dibasic anhydride monomers were added in batches), and the reaction was stirred at room temperature to generate a polyamic acid (PAA) solution in an argon atmosphere;

3. First disperse 1g GQDs in 100mL thionyl chloride and 30mL benzene solution, reflux at 80°C for 12h, wash the reflux product with tetrahydrofuran, and dry for 12h to obtain acid chloride GQDs powder; then disperse 100mg GQDs powder in tetrahydrofuran In the solution, 20mg 2,6-diaminopyridine was added, and under stirring at room temperature, argon flow was introduced to react for 6h, the product was dialyzed with a dialysis bag (molecular weight cut-off Da=500) for 3 days, and then the dialysis product was freeze-dried for 3 days to obtain Aminopyridine functionalized graphene quantum dots (FGQDs-2);

4. Add 1wt% of functionalized graphene quantum dots (FGQDs-2) to the PAA solution, stir to obtain a mixed solution, spin-coat the mixed solution to obtain a polyamic acid composite film, and then pass through 100 ℃, 200 ℃, After gradient imidization at 300°C, 350°C, and 400°C, a low-dielectric polyimide/graphene quantum dot composite film was obtained.

The polyimide film obtained above has an average thickness of 15 μm, a dielectric constant of 2.86@1MHz, a water absorption rate of 0.71%, and a thermal expansion coefficient of 28.5ppm/°C.

Example 3

1. Combine 10mmol 2,2-bis(3-aminophenyl)hexafluoropropane (3,3'-6FDAm) and 10mmol 4,4'-(1-phenyl-2,2,2-trifluoroethylidene ) diphthalic anhydride (3FDA) is successively dissolved in 40mL N-methyl pyrrolidone solvent (dibasic anhydride monomer is added in batches), and stirring reaction generates polyamic acid (PAA) solution under nitrogen atmosphere and room temperature;

3. First disperse 1g GQDs in 100mL thionyl chloride and 30mL benzene solution, reflux at 80°C for 12h, wash the reflux product with tetrahydrofuran, and dry for 12h to obtain acid chloride GQDs powder; then disperse 100mg GQDs powder in tetrahydrofuran In the solution, 20mg 2,5-diaminopyridine was added, and under stirring at room temperature, a nitrogen stream was introduced to react for 6h, the product was dialyzed with a dialysis bag (molecular weight cut-off Da=500) for 3 days, and the dialysis product was freeze-dried for 3 days to obtain Aminopyridine functionalized graphene quantum dots (FGQDs-3);

4. Add 1wt% of functionalized graphene quantum dots (FGQDs-3) to the PAA solution, stir to obtain a mixed solution, spin the mixed solution to obtain a polyamic acid composite film, and then pass through 100 ℃, 200 ℃, After gradient imidization at 300°C, 350°C, and 400°C, a low-dielectric polyimide/graphene quantum dot composite film was obtained.

The polyimide film obtained above has an average thickness of 15 μm, a dielectric constant of 2.74@1MHz, a water absorption rate of 0.81%, and a thermal expansion coefficient of 26.3ppm/°C.

Example 4

1. Combine 10mmol of 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane (BDAF) and 10mmol of 9-trifluoromethyl-9-phenylxanthene dianhydride (3FXDA) Dissolved successively in 45mL N-methylpyrrolidone solvent (dibasic anhydride monomers were added in batches), stirred and reacted in an argon atmosphere at room temperature to generate a polyamic acid (PAA) solution;

3. First disperse 1g GQDs in 100mL thionyl chloride and 30mL benzene solution, reflux at 80°C for 12h, wash the reflux product with tetrahydrofuran, and dry for 12h to obtain acid chloride GQDs powder; then disperse 100mg GQDs powder in tetrahydrofuran In the solution, 20 mg of 3,4-diaminopyridine was added, and under stirring at room temperature, a nitrogen stream was introduced to react for 6 h, the product was dialyzed with a dialysis bag (molecular weight cut-off Da=500) for 3 days, and the dialysis product was freeze-dried for 3 days to obtain Aminopyridine functionalized graphene quantum dots (FGQDs-4);

4. Add 1wt% of functionalized graphene quantum dots (FGQDs-4) into the PAA solution, stir to obtain a mixed solution, spin the mixed solution to obtain a polyamic acid composite film, and then pass through 100 ℃, 200 ℃, After gradient imidization at 300°C, 350°C, and 400°C, a low-dielectric polyimide/graphene quantum dot composite film was obtained.

The polyimide film obtained above has an average thickness of 15 μm, a dielectric constant of 2.54@1MHz, a water absorption rate of 0.60%, and a thermal expansion coefficient of 29.1ppm/°C.

In the description of this specification, reference is made to the description of the terms "one embodiment", "some embodiments", "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc. It is intended that a particular feature, structure, material or characteristic described in connection with this embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms 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 above content is a further detailed description of the present invention in conjunction with specific embodiments, and it cannot be considered that the specific implementation of the present invention is limited to these descriptions. For those of ordinary skill in the technical field to which the present invention pertains, some simple deductions or substitutions can also be made without departing from the concept of the present invention.

Claims

A method for preparing a low-dielectric polyimide composite film material is characterized by comprising the following steps: first dissolving a diamine monomer and a dibasic anhydride monomer in an organic solvent, respectively; adding in batches; reacting for a preset time to obtain a polyamic acid solution; using citric acid hydrothermal method to prepare graphene quantum dots, and then performing amidation reaction with diaminopyridine and graphene quantum dots to obtain aminopyridine-functionalized graphite Graphene quantum dots; the polyamic acid solution and the functionalized graphene quantum dots are stirred at room temperature to obtain a mixed solution; the mixed solution is spin-coated to obtain a polyamic acid composite film, which is then subjected to gradient imidization treatment within a certain temperature range. A low-dielectric polyimide composite film material was obtained.
The method for preparing a low-dielectric polyimide composite film material according to claim 1, wherein the molar mass ratio of the diamine monomer and the dibasic anhydride monomer is 1: ( 1-1.2); the ratio of the sum of the mass of the diamine monomer and the dibasic anhydride monomer to the mass of the organic solvent is (0.5-2.5):10.
The method for preparing a low-dielectric polyimide composite film material according to claim 1, wherein the organic solvent is N,N-dimethylacetamide, N,N-dimethylacetamide One or more of formamide and N-methylpyrrolidone.
The method for preparing a low-dielectric polyimide composite film material according to claim 1, wherein the dibasic anhydride monomer is one of 6FDA, 6FXDA, PFPDA, 3FDA, 3FXDA, and 3FX3FXDA. One or more of , whose molecular structural formula is as follows:
The method for preparing a low-dielectric polyimide composite film material according to claim 1, wherein the temperature range for preparing graphene quantum dots by the citric acid hydrothermal method is 160-240°C.
The method for preparing a low-dielectric polyimide composite film material according to claim 1, wherein the diamine monomer is TFMOB, 3,3'-6FDAm, 3FDAm, TFMB, 4 , more than one of 4'-6FDAm or BDAF, and its molecular structure is as follows:
The method for preparing a low-dielectric polyimide composite film material according to claim 1, wherein the diaminopyridine is 2,3-diaminopyridine, 2,6-diaminopyridine, One or more of 2,5-diaminopyridine and 3,4-diaminopyridine.
The method for preparing a low-dielectric polyimide composite film material according to claim 1, wherein the gradient imidization temperature range of the polyamic acid composite film is 100-400°C.
A low-dielectric polyimide composite film material, characterized in that, the low-dielectric polyimide composite film material is prepared by the preparation method of any one of claims 1-8.