CN112625017B - A kind of amide dianhydride, its preparation method and application - Google Patents

Abstract

The invention relates to the technical field of flexible electronics and flexible display, in particular to an amide dianhydride, a preparation method and application thereof. The amide dianhydride has a structure shown in a formula (I) or a formula (II): wherein Q is ₁ And Q ₂ Independently selected from phenyl, cyclohexyl, substituted phenyl or substituted cyclohexyl; y is selected from one or more of a substituted aromatic group, a substituted alicyclic group and a substituted aliphatic group. The transparent polyimide film prepared from the amide dianhydride has better comprehensive performance. Experimental results show that the average light transmittance (measured by a UV spectrometer based on the film thickness of 30 μm) of the transparent polyimide film prepared by the invention at the wavelength of 380-780 nm is not less than 88%, the Coefficient of Thermal Expansion (CTE) at 100-300 ℃ is not more than 25 ppm/DEG C, and the tensile strength>150MPa, modulus>2.0GPa, and the surface energy is 25-40 mN/m.

Description

A kind of amide dianhydride, its preparation method and application

Technical field

The present invention relates to the technical fields of flexible electronics and flexible display, and in particular to an amide dianhydride, its preparation method and application.

Background technique

In the fields of flexible electronics and flexible displays, it is usually necessary to replace hard transparent materials such as glass with transparent polymer film materials to achieve thinner, lighter and more flexible devices. For example, flexible OLED displays, flexible LCD displays, flexible solar cells, flexible sensors, flexible transparent heaters, flexible touch, flexible transparent printed circuits, wearable devices, etc. At present, polyimide film materials usually use fully aromatic polyimide obtained by the condensation polymerization reaction of aromatic tetracarboxylic dianhydride and aromatic diamine. It exhibits a deep amber color and is difficult to be used in high transparency fields. In order to achieve high transparency, alicyclic monomers or fluorine-containing monomers are usually used to produce colorless and transparent polyimides. However, these transparent polyimides usually have low modulus and strength, and have high thermal expansion coefficients. When alicyclic monomers are used, the charge transfer complex that produces color is eliminated, and it has good transparency. However, these alicyclic structures have a tortuous conformation, usually in a cis configuration, and the molecular chains are loosely packed. , so these alicyclic transparent polyimides usually have a high thermal expansion coefficient, and at the same time, the alicyclic polyimide has poor heat resistance, losing the heat resistance advantage of polyimide. However, low thermal expansion coefficient and high heat resistance are necessary properties for flexible electronics and flexible displays, such as flexible display panels or flexible printed circuits, which require transparent polyimide film materials with low linear thermal expansion coefficient (CTE Not exceeding 25ppm/K). In the application of flexible electronics and flexible displays, the required colorless and transparent polyimide film must have the characteristics of high transparency, high strength, bending resistance, low thermal expansion coefficient, and high temperature resistance.

Transparent polyimide films used in flexible displays and flexible electronics need to form a laminated composite structure with other organic or inorganic layers, which requires sufficient bonding strength between layers. Transparent polyimide is usually made of fluorine-containing or grease-containing materials. The ring structure has lower polarity, which results in lower surface energy and greatly reduces the interlayer bonding force. This has also become a problem in the development of transparent polyimide. Therefore, the current transparent polyimide is not satisfactory in many flexible fields.

Contents of the invention

In view of this, the technical problem to be solved by the present invention is to provide an amide dianhydride, its preparation method and application. The transparent polyimide prepared from the amide dianhydride provided by the present invention has better comprehensive properties.

The invention provides an amide dianhydride having a structure shown in formula (I) or formula (II):

Wherein, Q ₁ and Q ₂ are independently selected from phenyl, cyclohexyl, substituted phenyl or substituted cyclohexyl;

Y is selected from one or more types of substituted aromatic groups, substituted alicyclic groups and substituted aliphatic groups.

In certain embodiments of the present invention, Q ₁ and Q ₂ are independently selected from the structure represented by formula (Q-1) or formula (Q-2);

In certain embodiments of the present invention, Y is selected from the group consisting of structures represented by formula (Y-1), formula (Y-2), formula (Y-3) or formula (Y-4);

Wherein, R ₁ , R ₂ , R ₃ and R ₄ are independently selected from hydrogen, alkyl, cycloalkyl, fluoroalkyl, ester or halogen;

R ₈ is selected from one of the structures shown in formulas (4-1) to (4-10);

In certain embodiments of the invention, R ₁ , R ₂ , R ₃ and R ₄ are independently selected from -H, -F, CH ₃ or -CF ₃ .

In certain embodiments of the present invention, the Y is selected from the group consisting of structures represented by formulas (Y-5) to (Y-16);

In some embodiments of the present invention, Y is a disubstituted aliphatic chain with no more than 20 carbon atoms, and the aliphatic chain contains 1 to 2 unsaturated groups.

In certain embodiments of the present invention, the amide dianhydride having the structure represented by formula (I) is selected from the group consisting of structures represented by formulas (1) to (4);

In certain embodiments of the present invention, the amide dianhydride having the structure shown in formula (II) is selected from the group consisting of having the structure shown in formulas (5) to (15);

The substituents R ₅ , R ₆ and R ₇ on the aromatic ring are independently selected from -H, -F, CH ₃ or -CF ₃ , and the same aromatic ring may contain multiple identical or different substituents. .

The present invention also provides a method for preparing the above-mentioned amide dianhydride, which includes the following steps:

The diacid compound having the structure represented by formula (T1-1) undergoes a dehydration cyclization reaction to obtain an amide dianhydride having the structure represented by formula (I);

Or the tetraacid compound having the structure shown in formula (T2-1) undergoes dehydration cyclization reaction to obtain the amide dianhydride having the structure shown in formula (II);

Wherein, Q ₁ and Q ₂ are independently selected from phenyl, cyclohexyl, substituted phenyl or substituted cyclohexyl;

Y is selected from one or more types of disubstituted aromatic groups, disubstituted alicyclic groups and disubstituted aliphatic groups.

In the preparation method of the amide dianhydride, the selection groups of Q ₁ , Q ₂ and Y are the same as above and will not be described again.

In certain embodiments of the present invention, the diacid compound having the structure shown in formula (T1-1) is prepared according to the following method:

Amidation reaction is carried out between an ortho-dicarboxyl group-containing amine having a structure represented by formula (T1-2) and an acid chloride having a structure represented by formula (T1-3) to obtain a diacid having a structure represented by formula (T1-1) compound;

In some embodiments of the present invention, the temperature of the amidation reaction is 0-40°C, and the time of the amidation reaction is 5-24 hours.

In certain embodiments of the invention, the amidation reaction is carried out in a first solvent.

In certain embodiments of the invention, the first solvent includes dichloromethane, chloroform, ethyl acetate, acetonitrile, acetone, methyl ethyl ketone, tetrahydrofuran, 1,4-dioxane, toluene, N-methyl -One or more of 2-pyrrolidone, dimethylformamide and dimethylacetamide.

In some embodiments of the present invention, the molar ratio of the ortho-dicarboxyl group-containing amine having the structure represented by formula (T1-2) to the acid chloride having the structure represented by formula (T1-3) is 1 to 2: 0.95 to 1.05. In certain embodiments, the molar ratio of the ortho-dicarboxyl group-containing amine having the structure represented by formula (T1-2) to the acid chloride having the structure represented by formula (T1-3) is 1:1 or 2:1.

In some embodiments of the present invention, after the amidation reaction, filtration and drying of the filtered solid material are also included. The present invention has no special restrictions on the filtration and drying methods, and filtration and drying methods well known to those skilled in the art can be used.

After obtaining the diacid compound having the structure represented by formula (T1-1), the diacid compound having the structure represented by formula (T1-1) is subjected to a dehydration cyclization reaction to obtain the amide diamide having the structure represented by formula (I). anhydride.

Specifically, it can be: mixing the diacid compound having the structure represented by formula (T1-1) and a third solvent, and heating to azeotropic dehydration and cyclization.

The third solvent can promote the water eliminated by dehydration and cyclization to leave the reaction system and accelerate the equilibrium reaction toward product formation, such as: benzene, toluene, xylene, o-dichlorobenzene, cyclohexanone, tert-butanol, methylcyclohexanone, etc. One or more of hexanone, acetic acid and cyclopentanone. The third solvent can also be an additional high boiling point solvent to improve the solubility of the reactants and promote the reaction, such as: N,N-dimethylacetamide, N,N-dimethylformamide, N-methyl -One or more of 2-pyrrolidone, cyclohexanone, dimethyl sulfoxide and γ-butyrolactone.

Alternatively, a chemical dehydrating agent may be added to the diacid compound having the structure represented by formula (T1-1) to promote dehydration and cyclization. These chemical dehydrating agents can be selected from one or more of acetic anhydride, sulfoxide chloride and phosphorus trichloride. In some embodiments of the present invention, the molar ratio of the diacid compound having the structure represented by formula (T1-1) to the chemical dehydrating agent is 1:2-15. In some embodiments, the molar ratio of the diacid compound having the structure shown in Formula (T1-1) to the chemical dehydrating agent is 1:5, 1:3, 1:4, 1:6, 1:10, 1:12, 1:15 or 1:12.5.

It can also be: adding a tertiary amine catalyst to the diacid compound with the structure shown in formula (T1-1). The optional tertiary amine catalyst includes one or more of pyridine, picoline, triethylamine and isoquinoline. kind.

In some embodiments of the present invention, the temperature of the dehydration cyclization reaction is 40-200°C, and the time of the dehydration cyclization reaction is 3-28 hours. In certain embodiments, the temperature of the dehydration cyclization reaction is 100°C, 110°C, 130°C, 80°C or 120°C. In some embodiments, the dehydration cyclization reaction time is 3h, 12h, 8h, 4h, 5h, 7h, 10h, 6h, 15h, 9h or 11h.

In some embodiments of the present invention, after the dehydration cyclization reaction, cooling, filtration and drying are also included. The present invention has no special restrictions on the cooling, filtration and drying methods, and any cooling, filtration and drying methods well known to those skilled in the art can be used.

In certain embodiments of the present invention, the tetra-acid compound having the structure shown in formula (T2-1) is prepared according to the following method:

Amidation reaction is carried out between an ortho-dicarboxyl group-containing amine having a structure represented by formula (T2-2) and an acid chloride having a structure represented by formula (T2-3) to obtain a diacid having a structure represented by formula (T2-1) compound;

In some embodiments of the present invention, the temperature of the amidation reaction is 0-40°C, and the time of the amidation reaction is 5-24 hours.

In certain embodiments of the invention, the amidation reaction is performed in a second solvent.

In certain embodiments of the invention, the second solvent includes dichloromethane, chloroform, ethyl acetate, acetonitrile, acetone, methyl ethyl ketone, tetrahydrofuran, 1,4-dioxane, toluene, N-methyl -One or more of 2-pyrrolidone, dimethylformamide and dimethylacetamide.

In some embodiments of the present invention, the molar ratio of the ortho-dicarboxyl group-containing amine having the structure represented by formula (T2-2) and the acid chloride having the structure represented by formula (T2-3) is 2:0.95～ 1.05.

In some embodiments of the present invention, after the amidation reaction, filtration and drying of the filtered solid material are also included. The present invention has no special restrictions on the filtration and drying methods, and filtration and drying methods well known to those skilled in the art can be used.

After obtaining the tetraacid compound having the structure shown in formula (T2-1), the tetraacid compound having the structure shown in formula (T2-1) is subjected to a dehydration cyclization reaction to obtain the amide diamide having the structure shown in formula (II). anhydride.

Specifically, it can be: mixing the tetra-acid compound having the structure represented by formula (T2-1) and the fourth solvent, and heating to perform azeotropic dehydration and cyclization.

The fourth solvent can promote the water eliminated by dehydration and cyclization to leave the reaction system and accelerate the equilibrium reaction toward product formation, such as: benzene, toluene, xylene, o-dichlorobenzene, cyclohexanone, tert-butanol, methylcyclohexanone, etc. One or more of hexanone, acetic acid and cyclopentanone. The fourth solvent can also be an additional high boiling point solvent to improve the solubility of the reactants and promote the reaction, such as: N,N-dimethylacetamide, N,N-dimethylformamide, N-methyl -One or more of 2-pyrrolidone, cyclohexanone, dimethyl sulfoxide and γ-butyrolactone.

Alternatively, a chemical dehydrating agent may be added to the tetraacid compound having the structure represented by formula (T2-1) to promote dehydration and cyclization. These chemical dehydrating agents can be selected from one or more of acetic anhydride, sulfoxide chloride and phosphorus trichloride. In some embodiments of the present invention, the molar ratio of the tetra-acid compound having the structure represented by formula (T2-1) to the chemical dehydrating agent is 1:2-6.

It can also be: adding a tertiary amine catalyst to the tetraacid compound having the structure shown in formula (T2-1). The optional tertiary amine catalyst includes one of pyridine, picoline, triethylamine and isoquinoline or Several kinds.

In some embodiments of the present invention, the temperature of the dehydration cyclization reaction is 40-200°C, and the time of the dehydration cyclization reaction is 4-28 hours.

In some embodiments of the present invention, after the dehydration cyclization reaction, cooling, filtration and drying are also included. The present invention has no special restrictions on the cooling, filtration and drying methods, and any cooling, filtration and drying methods well known to those skilled in the art can be used.

The preparation method of amide dianhydride provided by the invention can obtain amide dianhydride with higher yield.

The present invention also provides a transparent polyimide, which is prepared from the above-mentioned amide dianhydride; or is prepared from the above-mentioned amide dianhydride prepared by the preparation method.

Specifically, the transparent polyimide undergoes a polycondensation reaction from a dianhydride monomer and a diamine monomer to obtain a polyamic acid precursor, which is then imidized to obtain a transparent polyimide. The dianhydride monomers include the amide dianhydrides described above.

In certain embodiments of the present invention, the dianhydride monomer further includes hexafluorodianhydride and/or biphenyl dianhydride. In certain embodiments of the present invention, the molar ratio of the above-mentioned amide dianhydride and hexafluorodianhydride is 1˜4:1, 1:1 or 4:1. In certain embodiments of the present invention, the molar ratio of the above-mentioned amide dianhydride and biphenyl dianhydride is 3:2.

In certain embodiments of the invention, the diamine monomer is selected from the group consisting of 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl, 3,3'-bis(trifluoromethyl)- Methyl)-4,4'-diaminobiphenyl, 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, p-phenylenediamine, m-phenylenediamine, 2,5 -Diaminotoluene, 2,6-diaminotoluene, N-(4-aminophenyl)-4-aminobenzamide, 4-aminobenzoate (4-aminophenol) ester, 1,3-bis(4 ,4'-Aminophenoxy)benzene, 4,4'-diamino-1,5-phenoxypentane, 3,3'-dimethyl-4,4'-benzidine, 3,3' -Dimethoxy-4,4'-benzidine, 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl ether, 4,4'-diaminodiphenylmethane, 2, 2'-diaminodiphenylpropane, bis(3,5-diethyl-4-aminophenyl)methane, 4,4'-diaminodiphenyl sulfone, 3,3'-diaminodiphenyl sulfone, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)diphenylsulfone, 2, 2-bis[4-(4-aminophenoxy)phenyl]propane, 2,2'-diaminodiphenylpropane, trans-1,4-cyclohexanediamine, cis-1,4- Cyclohexanediamine, 1,3-diaminocyclohexane, 1,4-cyclohexanebis(methylamine), 4,4'-diaminodicyclohexylmethane and 4,4'-methylenebis( 2-methylcyclohexylamine).

In certain embodiments of the present invention, the molar ratio of the dianhydride monomer and diamine monomer is 100:95-105. In certain embodiments, the molar ratio of the dianhydride monomer and diamine monomer is 100:100.

In some embodiments of the present invention, the transparent polyimide is prepared according to the following method:

A) Perform a polycondensation reaction between the dianhydride monomer and the diamine monomer to obtain a polyimide precursor solution;

B) Imidize the polyimide precursor solution to obtain a transparent polyimide.

The components and proportions of the dianhydride monomer and diamine monomer mentioned in the preparation method of the transparent polyimide are the same as above, and will not be described again here.

In some embodiments of the present invention, the dianhydride monomer and diamine monomer undergo a polycondensation reaction in a fifth solvent.

In certain embodiments of the invention, the fifth solvent includes N,N-dimethylacetamide, N,N-dimethylformamide, N-methyl-2-pyrrolidone, m-cresol, N - One or two of methylcaprolactam, sulfolane, dimethyl sulfoxide (DMSO), cyclohexanone, hexamethylphosphoramide and γ-butyrolactone.

In some embodiments of the present invention, the temperature of the polycondensation reaction is not higher than 60°C, and the time of the polycondensation reaction is 10 minutes to 30 hours. In some embodiments, the temperature of the polycondensation reaction is 0-50°C. In certain embodiments, the temperature of the polycondensation reaction is 25°C, 10°C, 0°C, 30°C, 15°C, 20°C or 5°C. In some embodiments, the time of the polycondensation reaction is 12h, 24h, 15h, 13h, 10h, 17h or 18h.

In some embodiments of the present invention, the polycondensation reaction is carried out under protective gas conditions. In some embodiments, the protective gas is nitrogen.

In some embodiments of the present invention, after the polycondensation reaction, filtration is also included. The present invention has no special restrictions on the filtration method, and any filtration method well known to those skilled in the art can be used.

In some embodiments of the present invention, the polyimide precursor solution has a rotational viscosity of 4.7×10 ⁴ mPa/s and a logarithmic viscosity of 1.5 dL/g.

After obtaining the polyimide precursor solution, the polyimide precursor solution is imidized to obtain a transparent polyimide.

In some embodiments of the present invention, the imidization may be thermal imidization or chemical imidization.

In some embodiments of the present invention, the thermal sublimation method uses heating to gradually increase the temperature from 80°C to 400°C to perform dehydration and cyclization of amic acid to achieve imidization.

In some embodiments of the present invention, the chemical imidization is achieved by adding a chemical dehydrating agent to perform dehydration and cyclization of amic acid.

In certain embodiments of the invention, the chemical dehydrating agent is selected from acetic anhydride or benzoic anhydride. Catalysis can be carried out using organic bases such as pyridine, triethylamine or isoquinoline as catalysts. In some embodiments of the present invention, the molar ratio of the chemical dehydrating agent to the dianhydride monomer is 2 to 10:1. In certain embodiments, the molar ratio of the chemical dehydrating agent to the dianhydride monomer is 5:1, 4:1, 3:1 or 7:1. In some embodiments of the present invention, the molar ratio of the catalyst to the dianhydride monomer is 2 to 10:1. In certain embodiments, the molar ratio of the catalyst to the dianhydride monomer is 5:1, 4:1, 3:1 or 7:1.

In some embodiments of the present invention, the temperature for dehydrating and cyclizing the amic acid by adding a chemical dehydrating agent is -20 to 200°C, and the time is 2 to 10 hours. In certain embodiments, the dehydration cyclization temperature is 25°C, 27°C, 20°C, 10°C, or 15°C. In some embodiments, the dehydration cyclization time is 4h, 2h or 3h.

After the polyimide precursor solution is imidized, a transparent polyimide solution is obtained.

In some embodiments of the present invention, after the imidization, the method further includes: mixing the transparent polyimide solution and the sixth solvent to precipitate a white precipitate, filtering and drying to obtain a transparent polyimide.

In certain embodiments of the invention, the sixth solvent is selected from methanol or ethanol.

The present invention has no special restrictions on the filtration and drying methods, and filtration and drying methods well known to those skilled in the art can be used.

In some embodiments of the present invention, the raw materials for preparing transparent polyimide also include fillers. The filler includes one or more of silica, tetraalkoxysilane, polysiloxane, siloxane surfactant and siloxane coupling agent. Specifically, it can be selected from nano silica. , tetramethoxysilane, tetraethoxysilane, tetrabutoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxy One or three of silane, 3-glycidoxypropyltriethoxysilane, polyethersiloxane and polyphenylsilsesquioxane. The filler is added before or after the polyamic acid precursor is obtained by polymerization. The mass ratio of the added amount of the filler to the polyamic acid precursor is 0.01 to 30:100. In some embodiments, the mass ratio of the added amount of filler to the polyamic acid precursor is 0.1 to 15:100.

The present invention also provides a transparent polyimide film, which is prepared from the transparent polyimide described above.

In some embodiments of the present invention, the transparent polyimide film is obtained by coating a solution of transparent polyimide on the surface of a support and performing an imidization reaction.

In some embodiments of the present invention, the transparent polyimide solution may be the transparent polyimide solution obtained after imidization as described above, or the polyimide solution as described above. A precursor solution, or a solution of transparent polyimide prepared by dissolving transparent polyimide in the seventh solvent. In certain embodiments of the invention, the seventh solvent is selected from m-cresol, N,N-dimethylacetamide, N,N-dimethylformamide, N-methyl-2-pyrrolidone, One or more of cyclohexanone and γ-butyrolactone. In some embodiments of the present invention, the mass concentration of the transparent polyimide solution is 20%.

In some embodiments of the invention, the support is a glass plate.

In some embodiments of the present invention, the imidization may be thermal imidization or chemical imidization.

In some embodiments of the present invention, the thermal sublimation can use a heating method to gradually increase the temperature from 80°C to 400°C to achieve imidization. In certain embodiments, the temperature is heated from 80°C to 280°C, or the temperature is heated from 80°C to 300°C, or the temperature is heated from 80°C to 320°C. In some embodiments of the present invention, the thermal sublimation temperature is 250-350°C.

In some embodiments of the present invention, the chemical imidization is achieved by adding a chemical dehydrating agent.

In certain embodiments of the invention, the chemical dehydrating agent is selected from acetic anhydride or benzoic anhydride. Catalysis can be carried out using organic bases such as pyridine or triethylamine as catalysts. In some embodiments of the present invention, the mass ratio of the chemical dehydrating agent to the dianhydride monomer is 2 to 10:1. In some embodiments of the present invention, the mass ratio of the catalyst to the dianhydride monomer is 2 to 10:1.

In some embodiments of the present invention, the temperature for dehydrating and cyclizing the amic acid by adding a chemical dehydrating agent is -20 to 200°C, and the time is 2 to 10 hours.

In the present invention, the polyimide film formed through the imidization reaction can be subjected to the imidization reaction again to remove thermal hysteresis and residual stress from the film, improve thermal stability, and reduce the thermal expansion coefficient.

The present invention has no special restrictions on the source of the raw materials used above, and they can be generally commercially available.

In some embodiments of the present invention, the thickness of the polyimide film is 10-250 μm. In some embodiments, the thickness of the polyimide film is 10-100 μm.

The surface of the formed polyimide film can directly form the functional layer necessary for flexible display; the polyimide film can also be peeled off from the surface of the support to obtain a self-supporting film material, and the necessary functional layer for flexible display can be processed on the surface.

The transparent polyimide provided by the present invention has excellent properties such as transparency, high heat resistance, and low linear thermal expansion coefficient. It has high surface energy and is suitable for improving interlayer bonding force. For example, when using it to construct a multi-layer composite membrane structure, its low thermal expansion coefficient and sufficient inter-layer bonding force can not only adapt to the thermal expansion properties of inorganic or metal film layer materials, but also improve the inter-layer bonding, thereby improving the performance of the composite membrane. Dimensional stability of horizontal and vertical methods during high temperature processing, reducing the risk of deformation and delamination.

The transparent polyimide film prepared from the amide dianhydride provided by the invention has better comprehensive properties. Experimental results show that the average transmittance of the transparent polyimide film prepared by the present invention at a wavelength of 380-780 nm (based on a film thickness of 30 μm, measured by a UV spectrometer) is not less than 88%, and the average transmittance at 100-300°C The thermal expansion coefficient (CTE) does not exceed 25ppm/℃, the tensile strength is >150MPa, the modulus is >2.0GPa, the surface energy is 25~40mN/m, and the surface energy is high, which is beneficial to its bonding with the functional layer.

Description of drawings

Figure 1 is a hydrogen nuclear magnetic spectrum of the amide dianhydride in Example 1 of the present invention;

Figure 2 is a nuclear magnetic carbon spectrum of the amide dianhydride in Example 1 of the present invention;

Figure 3 is a hydrogen nuclear magnetic spectrum of the amide dianhydride in Example 2 of the present invention;

Figure 4 is a nuclear magnetic carbon spectrum of the amide dianhydride in Example 2 of the present invention;

Figure 5 is a hydrogen nuclear magnetic spectrum of the amide dianhydride in Example 5 of the present invention;

Figure 6 is a nuclear magnetic carbon spectrum of the amide dianhydride in Example 5 of the present invention;

Figure 7 is a hydrogen nuclear magnetic spectrum of the amide dianhydride in Example 6 of the present invention;

Figure 8 is the NMR carbon spectrum of the amide dianhydride in Example 6 of the present invention;

Figure 9 is a hydrogen nuclear magnetic spectrum of the amide dianhydride in Example 16 of the present invention;

Figure 10 is a carbon NMR spectrum of the amide dianhydride in Example 16 of the present invention.

Detailed ways

The technical solution of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention.

The raw materials used in the following examples are all commercially available.

The instruments, equipment and parameter conditions used in the examples are as follows:

1. Nuclear magnetic resonance: Bruker300 nuclear magnetic resonance spectrometer, Bruker Company, Germany;

2. Infrared spectrum: Vertex 70 Fourier transform infrared spectrometer (FTIR) instrument, Bruker Company, Germany, test range 4000-600cm ^-1 ;

3. Coefficient of thermal expansion (CTE): Tested using Thermo plas TMA thermomechanical analyzer (TMA, TA company Q400); test conditions: 10℃/min, 100~300℃ range;

4. Tensile test: NSTRON-1121 electronic universal testing machine, tensile rate 5mm/min;

5. Optical transmittance: Shimadzu Uv-2550 UV-visible spectrum tester, average transmittance at wavelengths of 380 to 780nm;

6. Glass transition temperature (Tg): DSC Perkin-Elmer DSC-7 tests thin film materials, nitrogen atmosphere, heating rate 10°C/min;

7. Rotational viscosity: digital viscometer, room temperature;

8. Logarithmic viscosity ([eta]inh): Ubbelohde viscometer, 30°C.

Example 1

Add 3.623g (0.02mol) 4-aminophthalic acid and 80g tetrahydrofuran to the reaction vessel, stir, and add 4.2114g (0.02mol) trimellityl chloride in batches at 10°C, and the reaction proceeds for 15 hours. Filter, and the filtered solid powder is dried to obtain the diacid. The obtained diacid was added to 100g of xylene, heated to reflux at 100°C for 3 hours, cooled, filtered, and dried to obtain 6.556g of amide dianhydride, which has the structure shown in formula (1) and a yield of 97.2%. 1H NMR (400MHz, DMSO-d6) δ11.31(s,1H),8.64(s,1H),8.51(d,J＝6.1Hz,2H),8.27(d,J＝8.0Hz,2H),8.12 (d,J＝8.3Hz,1H).13C NMR(101MHz,DMSO-d6)δ164.7,162.3,141.0,139.3,134.5,132.6,132.2,132.1,129.8,127.7,127.5,126.7,119.8.

Figure 1 is a hydrogen nuclear magnetic spectrum of the amide dianhydride in Example 1 of the present invention.

Figure 2 is a NMR carbon spectrum of the amide dianhydride in Example 1 of the present invention.

Example 2

Add 3.623g (0.02mol) 4-aminophthalic acid and 100g acetonitrile to the reaction vessel, stir, and add 4.3324g (0.02mol) hydrogenated trimellityl chloride in batches at 10°C, and the reaction proceeds for 12 hours. Filter, and the filtered solid powder is dried to obtain the diacid. The obtained diacid was added to 120g of cyclohexanone, heated to reflux at 110°C for 12 hours, cooled, filtered, and dried to obtain 6.518g of amide dianhydride with the structure shown in formula (2), with a yield of 95.0%. 1H NMR (300MHz, DMSO-d6) δ10.73(s,1H),8.32(s,1H),7.98(dd,J＝21.6,8.3Hz,2H),3.67-3.47(m,1H),3.29( dd,J＝18.2,8.0Hz,1H),2.55(s,1H),2.20(d,J＝5.3Hz,1H),2.08(dd,J＝13.5,4.3Hz,1H),1.82(t,J ＝24.0Hz,2H),1.62(dd,J＝24.1,11.0Hz,1H),1.41(dd,J＝21.8,11.9Hz,1H).13C NMR(101MHz,DMSO-d6)δ172.9,172.2,162.3, 146.3,132.2,129.8,126.7,119.8,42.0,40.4,36.4,28.6,26.6,22.6.

Figure 3 is a hydrogen nuclear magnetic spectrum of the amide dianhydride in Example 2 of the present invention.

Figure 4 is a NMR carbon spectrum of the amide dianhydride in Example 2 of the present invention.

Example 3

Add 3.7438g (0.02mol) 1,2-dicarboxy-4-aminocyclohexane and 85g methylene chloride into the reaction vessel, stir, and add 4.2114g (0.02mol) trimellityl chloride in batches at 20°C. , the reaction was carried out for 10h. Filter, and the filtered solid powder is dried to obtain the diacid. The obtained diacid was added to a mixed solution of 150g toluene and 10.209g (0.1mol) acetic anhydride, heated to reflux at 130°C for 8 hours, cooled, filtered, and dried to obtain 6.5869g of amide dianhydride, which has the formula ( 3) The structure shown, the yield is 96%. 1H NMR(300MHz,DMSO-d6)δ8.60-8.58(m,2H),8.37(d,1H),8.03(s,1H),3.54-3.49(m,1H),2.9(m,2H), 2.05(m,2H),1.79(m,2H),1.54(m,2H).13C NMR(101MHz,DMSO-d6)δ172.2,167.2,162.3,139.3,134.5,132.6,132.1,127.7,127.5,48.8, 42.4,34.5,29.1,25.3,20.7.

Example 4

Add 3.7438g (0.02mol) 1,2-dicarboxy-4-aminocyclohexane and 68g tetrahydrofuran to the reaction vessel, stir, and add 4.6926g (0.02mol) hydrogenated trimellityl chloride in batches at 15°C. The reaction was carried out for 16h. Filter, and the filtered solid powder is dried to obtain the diacid. The obtained diacid was added to a mixed solution of 80g xylene and 10.209g acetic anhydride (0.1mol), heated to 80°C for 4 hours, cooled, filtered, and dried to obtain 6.777g amide dianhydride with formula (4 ), the yield is 97%. 1H NMR(300MHz,DMSO-d6)δ8.03(s,1H),3.54(m,1H),2.9(m,4H),2.38(m,1H),2.04(m,2H),1.80-1.74( m,6H),1.55-1.49(m,4H).13C NMR(101MHz,DMSO-d6)δ173.3,172.2,48.6,46.0,42.4,42.0,36.4,34.5,29.1,28.6,26.6,25.3,22.6,20.7 .

Example 5

Add 3.623g (0.02mol) 4-aminophthalic acid and 69g tetrahydrofuran to the reaction vessel, stir, and add 2.0302g (0.01mol) terephthaloyl chloride in batches at 20°C, and the reaction proceeds for 20 hours. Filter, and the filtered solid powder is dried to obtain tetraacid. The obtained tetraacid was added to a solution containing 6.13g (0.06mol) acetic anhydride and 100g xylene, heated to 120°C for 5 hours, cooled, filtered, and dried to obtain 4.38g bisamide dianhydride with formula (5) Structure shown, yield 96%. 1H NMR(300MHz,DMSO-d6)δ13.21(s,3H),10.75(s,2H),8.17–8.07(m,6H),8.03(dd,J＝8.6,1.9Hz,2H),7.79( d, J＝8.5Hz, 2H).13C NMR (101MHz, DMSO-d6) δ165.6,163.3,162.7,146.2,136.7,132.6,128.3,126.6,126.4,125.0,115.3.

Figure 5 is a hydrogen nuclear magnetic spectrum of the amide dianhydride in Example 5 of the present invention.

Figure 6 is a NMR carbon spectrum of the amide dianhydride in Example 5 of the present invention.

Example 6

Add 3.623g (0.02mol) 4-aminophthalic acid and 69g tetrahydrofuran to the reaction vessel, stir, and add 2.0302g (0.01mol) isophthaloyl chloride in batches at 20°C, and the reaction proceeds for 20 hours. Filter, and the filtered solid powder is dried to obtain tetraacid. The obtained tetraacid was added to a solution containing 8.16g (0.08mol) acetic anhydride and 100% xylene, heated to 120°C for 5 hours, cooled, filtered, and dried to obtain 4.335g bisamide dianhydride with formula (6) Structure shown, yield 95%. 1H NMR (300MHz, DMSO-d6) δ13.10 (s, 4H), 10.78 (s, 2H), 8.59 (s, 1H), 8.20 (dd, J = 7.8, 1.4Hz, 2H), 8.09 (d, J＝2.0Hz,2H),8.03(dd,J＝8.5,2.1Hz,2H),7.75(dd,J＝14.6,8.1Hz,3H).13C NMR(101MHz,DMSO-d6)δ165.7,163.3,162.7 ,146.1,134.3,132.8,131.5,129.0,127.6,126.6,126.5,125.1,115.1.

Figure 7 is a hydrogen nuclear magnetic spectrum of the amide dianhydride in Example 6 of the present invention.

Figure 8 is a NMR carbon spectrum of the amide dianhydride in Example 6 of the present invention.

Example 7

Add 3.623g (0.02mol) 4-aminophthalic acid and 69g 1,4-dioxane to the reaction vessel, stir, and add 2.0907g (0.01mol) 1,4-cyclohexane in batches at 30°C. Diformyl chloride, the reaction was carried out for 15h. Filter, and the filtered solid powder is dried to obtain tetraacid. The obtained tetraacid was added to a solution containing 12.25g (0.12mol) acetic anhydride and 90g toluene, heated to 110°C for 7 hours, cooled, filtered, and dried to obtain 4.39g bisamide dianhydride, which has the formula (7) The structure is shown, and the yield is 95%. 1H NMR(300MHz,DMSO-d6)δ8.66(s,2H),8.40(d,2H),8.21(dd,2H),7.23(s,2H),2.38(m,2H),1.91(m, 4H),1.66(m,4H).13C NMR(101MHz,DMSO-d6)δ172.9,162.3,146.3,132.2,129.8,126.7,119.8,42.8,26.2.

Example 8

Add 3.623g (0.02mol) 4-aminophthalic acid and 50g ethyl acetate to the reaction vessel, stir, and add 2.7912g (0.01mol) 4,4'-biphenyl dicarboxylic acid chloride in batches at 10°C. , the reaction was carried out for 20h. Filter, and the filtered solid powder is dried to obtain tetraacid. The obtained tetraacid was added to a solution containing 8.16g (0.08mol) acetic anhydride and 75g toluene, heated to 110°C for 10 hours, cooled, filtered, and dried to obtain 5g bisamide dianhydride, with formula (8) Structure, yield 94%. 1H NMR(300MHz,DMSO-d6)δ9.15(s,2H),8.66(d,2H),8.52(dd,2H),8.40(d,2H),8.21(dd,2H),8.09(dd, 2H),7.76(m,2H),7.59(m,2H).13C NMR(101MHz,DMSO-d6)δ164.7,162.3,141.0,132.6,132.2,132.1,129.8,128.0,127.7,126.7,126.5,121.2, 119.8.

Example 9

Add 3.623g (0.02mol) 4-aminophthalic acid and 50g ethyl acetate to the reaction vessel, stir, and add 2.6114g (0.01mol) 1,3-adamantanedicarboxylic acid chloride in batches at 10°C. The reaction was carried out for 14h. Filter, and the filtered solid powder is dried to obtain tetraacid. The obtained tetraacid was added to a solution containing 20.42g (0.2mol) acetic anhydride and 120g xylene, heated to 120°C for 6 hours, cooled, filtered, and dried to obtain 4.99g bisamide dianhydride with formula (9) Structure shown, yield 97%. 1H NMR(300MHz,DMSO-d6)δ8.66(s,2H),8.40(d,2H),8.21(dd,2H),7.23(s,2H),2.36(t,1H),1.83(m, 3H),1.65(m,2H),1.58(m,3H),1.49(m,2H),1.43(m,1H),1.24(m,2H).13C NMR(101MHz,DMSO-d6)δ174.6,172.9 ,162.3,146.3,132.2,129.8,126.7,119.8,45.2,39.3,37.0,36.7,36.1,34.2,26.3.

Example 10

Add 3.623g (0.02mol) 4-aminophthalic acid and 60g butanone into the reaction vessel, stir, and add 4.2914g (0.01mol) 2,2'-bis(4-chlorocarbonyl) in batches at 30°C. phenyl) hexafluoropropane, the reaction was carried out for 24 h. Filter, and the filtered solid powder is dried to obtain tetraacid. The obtained tetraacid was added to a solution containing 25.52g (0.25mol) acetic anhydride and 120g xylene, heated to 120°C for 10 hours, cooled, filtered, and dried to obtain 6.48g bisamide dianhydride with formula (10) Structure shown, yield 95%. 1H NMR(300MHz,DMSO-d6)δ9.15(s,2H),8.66(dd,2H),8.40(d,2H),8.21(dd,2H),7.95(d,4H),7.58(d, 4H).13C NMR (101MHz, DMSO-d6) δ164.7,162.3,149.5,141.0,132.2,131.7,129.8,128.3,128.0,126.7,119.8,106.2,66.3.

Example 11

Add 3.623g (0.02mol) 4-aminophthalic acid and 80g tetrahydrofuran to the reaction vessel, stir, and add 4.4332g (0.01mol) 9,9-bis(4-chloroformylbenzene) in batches at 25°C. base) fluorene, the reaction was carried out for 12h. Filter, and the filtered solid powder is dried to obtain tetraacid. The obtained tetraacid was added to a solution containing 10.21g (0.1mol) acetic anhydride and 80g toluene, heated to 110°C for 6 hours, cooled, filtered, and dried to obtain 6.55g bisamide dianhydride with formula (11) The structure is shown, and the yield is 94%. 1H NMR(300MHz,DMSO-d6)δ9.15(s,2H),8.66(d,2H),8.40(d,2H),8.21(dd,2H),7.91(d,4H),7.87(dd, 2H),7.55(dd,2H),7.41(d,4H),7.38(m,2H),7.28(m,2H).13CNMR(101MHz,DMSO-d6)δ164.7,162.3,151.1,141.9,141.0,132.2 ,131.7,129.8,128.7,128.3,128.1,128.0,126.7,126.2,119.8,62.9.

Example 12

Add 3.7438g (0.02mol) 4-aminocyclohexane-1,2dicarboxylic acid and 65g dimethylacetamide into the reaction vessel, stir, and add 2.5308g (0.01mol) 2,7 in batches at 25°C. -Naphthalenedicarboxyl chloride, the reaction was carried out for 10 hours. Filter, and the filtered solid powder is dried to obtain tetraacid. The obtained tetraacid was added to a solution containing 24.5g (0.24mol) acetic anhydride and 70g xylene, heated to 120°C, reacted for 15h, cooled, filtered, and dried to obtain 5.1g bisamide dianhydride with formula (12 ), the yield is 98%. 1H NMR(300MHz,DMSO-d6)δ8.48(s,2H),8.13(d,2H),8.03(m,2H),7.98(m,2H),3.54(m,2H),2.9(m, 4H),2.05(m,4H),1.79(m,4H),1.54(m,4H).13C NMR(101MHz,DMSO-d6)δ172.2,167.2,137.4,134.9,131.2,130.0,127.9,126.5,48.8 ,42.4,34.5,29.1,25.3,20.7.

Example 13

Add 3.623g (0.02mol) 4-aminophthalic acid and 50g N-methylpyrrolidone to the reaction vessel, stir, and add 2.2108g (0.01mol) 2,5-dichloroformyl bicyclo in batches at 20°C. [2,2,1] Heptane, the reaction was carried out for 16 hours. Filter, and the filtered solid powder is dried to obtain tetraacid. The obtained tetraacid was added to a solution containing 30.63g (0.3mol) acetic anhydride and 100g toluene, heated to 110°C for 10 hours, cooled, filtered, and dried to obtain 4.55g bisamide dianhydride, which has the formula (13) The structure is shown, and the yield is 96%. 1H NMR(300MHz,DMSO-d6)δ8.66(d,2H),8.40(d,2H),8.21(dd,2H),7.23(s,2H),2.37(m,2H),2.13(m, 1H),1.88(m,3H),1.66-1.62(m,4H).13C NMR(101MHz,DMSO-d6)δ172.9,162.3,146.3,132.2,129.8,126.7,119.8,42.8,41.0,35.8,30.8.

Example 14

Add 3.623g (0.02mol) 4-aminophthalic acid and 55g acetonitrile to the reaction vessel, stir, add 3.4318g (0.01mol) 3,3'-sulfonylxylenyl chloride in batches at 25°C, and react Carry out for 10h. Filter, and the filtered solid powder is dried to obtain tetraacid. The obtained tetraacid was added to a solution containing 25.52g (0.25mol) acetic anhydride and 60g toluene, heated to 110°C for 9 hours, cooled, filtered, and dried to obtain 5.78g bisamide dianhydride, which has the formula (14) The structure is shown, and the yield is 97%. 1H NMR(300MHz,DMSO-d6)δ9.15(s,2H),8.66(dd,2H),8.45(m,2H),8.40(d,2H),8.28(m,2H),8.21(dd, 2H),8.03(m,2H),7.80(t,2H).13C NMR(101MHz,DMSO-d6)δ164.7,162.3,142.5,141.0,135.2,132.5,132.2,131.7,129.8,126.7,121.3,119.8.

Example 15

Add 3.623g (0.02mol) 4-aminophthalic acid and 60g dichloromethane to the reaction vessel, stir, and add 2.6316g (0.01mol) 3,8-dichloroformyl bicyclo[ 4,4,0]decane, the reaction was carried out for 15h. Filter, and the filtered solid powder is dried to obtain tetraacid. The obtained tetraacid was added to a solution containing 30.63g (0.3mol) acetic anhydride and 110g xylene, heated to 120°C for 11 hours, cooled, filtered, and dried to obtain 4.9g bisamide dianhydride with formula (15) Structure shown, yield 95%. 1H NMR(300MHz,DMSO-d6)δ8.66(d,2H),8.40(d,2H),8.21(dd,2H),7.23(s,2H),2.37(m,2H),1.91(m, 4H),1.64(m,2H),1.53(m,4H),1.27(m,4H).13C NMR(101MHz,DMSO-d6)δ172.9,162.3,146.3,132.2,129.8,126.7,119.8,43.7,40.5 ,27.5,24.1,22.5.

Example 16

Add 3.623g (0.02mol) 4-aminophthalic acid and 50g tetrahydrofuran to the reaction vessel, stir, and add 2.7498g (0.01mol) 2,3,5,6-tetrafluoroparaben in batches at 30°C. Diformyl chloride, the reaction was carried out for 11 hours. Filter, and the filtered solid powder is dried to obtain tetraacid. The obtained tetraacid was added to a solution containing 30.63g (0.3mol) acetic anhydride and 90g toluene, heated to 120°C for 6 hours, cooled, filtered, and dried to obtain 5.07g bisamide dianhydride with formula (16) The structure is shown, and the yield is 96%. ¹ H NMR (400MHz, DMSO) δ = 11.87 (s, 2H), 8.41 (s, 2H), 8.14 (d, J = 8.2, 2H), 8.06 (d, J = 8.3, 2H). 13C NMR (101MHz ,DMSO-d6)δ162.9,162.5,156.1,144.3,133.2,126.9,126.5,126.2,114.7.

Figure 9 is a hydrogen nuclear magnetic spectrum of the amide dianhydride in Example 16 of the present invention.

Figure 10 is a carbon NMR spectrum of the amide dianhydride in Example 16 of the present invention.

Example 17

Add 3.2023g (0.01mol) 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl and 37.26g dimethylacetamide into the reaction vessel, control the temperature to 6°C, and stir to dissolve. Add 3.3724g (0.01 mol) of the dianhydride compound with the structure shown in formula (1) in batches, perform a polymerization reaction at 25°C for 12 hours under nitrogen conditions, and filter to form a transparent polyimide precursor solution. The rotational viscosity was tested to reach 4.7×10 ⁴ mPa/s, and the logarithmic viscosity was 1.5dL/g. Add 5.1g (0.05mol) acetic anhydride and 5.06g (0.05mol) triethylamine to the precursor solution, and react at 25°C for 4 hours. The reaction mixture was slowly poured into ethanol, and a white filamentous precipitate precipitated. The filamentous precipitate was filtered out and dried to obtain a transparent polyimide resin. Dissolve this resin in N-methylpyrrolidone to form a 20% mass fraction solution, apply it on the surface of the glass plate, place it in an oven and heat it to 200°C to form a transparent polyimide film.

Example 18

Add 1.1419g (0.01mol) trans-1,4-cyclohexanediamine and 25.6g N-methyl-2-pyrrolidone to the reaction vessel, heat to 70°C to dissolve all the solids, cool to room temperature, and add 1.2g acetic acid , stir for 10 minutes. Add 3.3724g (0.01mol) of the dianhydride compound with the structure shown in formula (1) in batches, perform a polymerization reaction at 10°C for 12 hours under nitrogen conditions, and filter to form a transparent polyimide precursor solution. The rotational viscosity was tested to reach 3.0×10 ⁴ mPa/s, and the logarithmic viscosity was 1.2dL/g. This precursor solution is coated on the surface of the glass plate, placed in an oven, and heated at a gradient temperature from 80°C to 280°C to form a transparent polyimide film.

Example 19

Add 3.2023g (0.01mol) 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl and 37.6g dimethylacetamide into the reaction vessel, control the temperature not to exceed 10°C, and stir Dissolve. Add 3.4329g (0.01 mol) of the dianhydride compound with the structure shown in formula (2) in batches, perform a polymerization reaction at 0°C for 24 hours under nitrogen, and filter to form a transparent polyimide precursor solution. The rotational viscosity was tested to reach 4.6×10 ⁴ mPa/s, and the logarithmic viscosity was 1.6dL/g. Add 5.1g (0.05mol) acetic anhydride and 5.06g (0.05mol) triethylamine to the precursor solution. After stirring evenly, apply the reaction mixture on the surface of the glass plate and place it in an oven to heat to 200°C to form a transparent polyamide. imine film.

Example 20

Add 3.2023g (0.01mol) 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl and 37.6g N-methyl-2-pyrrolidone into the reaction vessel, control the temperature to 6°C, and stir Dissolve. 3.4329g (0.01mol) of the dianhydride compound with the structure shown in formula (3) was added in sequence, polymerized at 30°C for 15 hours under nitrogen, and filtered to form a transparent polyimide precursor solution. The rotational viscosity was tested to reach 4.7×10 ⁴ mPa/s, and the logarithmic viscosity was 1.6dL/g. Add 5.1g (0.05mol) acetic anhydride and 5.06g (0.05mol) pyridine to the precursor solution, and react at 27°C for 2 hours. The reaction mixture was slowly poured into methanol, and a white filamentous precipitate precipitated. The filamentous precipitate was filtered out and dried to obtain a transparent polyimide resin. Dissolve this resin in γ-butyrolactone to form a 20% mass fraction solution, apply it on the surface of the glass plate, place it in an oven and heat it to 200°C to form a transparent polyimide film.

Example 21

Add 3.2023g (0.01mol) 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl and 38g dimethylacetamide into the reaction vessel, control the temperature not to exceed 10°C, stir and dissolve . 3.4934g (0.01mol) of the dianhydride compound with the structure shown in formula (4) was added in sequence, polymerized at 15°C for 24 hours under nitrogen conditions, and filtered to form a transparent polyimide precursor solution. The rotational viscosity was tested to reach 4.8×10 ⁴ mPa/s, and the logarithmic viscosity was 1.7dL/g. This precursor solution is coated on the surface of the glass plate, placed in an oven, and heated at a gradient temperature from 80°C to 300°C to form a transparent polyimide film.

Example 22

Add 1.1419g (0.01mol) trans-1,4-cyclohexanediamine and 32.33g dimethylacetamide into the reaction vessel, control the temperature not to exceed 15°C, and stir to dissolve. Heat to 70°C to dissolve all the solids, cool to room temperature, add 1.2g acetic acid, and stir for 15 minutes. 4.5636g (0.01mol) of the dianhydride compound with the structure shown in formula (5) was added in sequence, polymerized at 20°C for 13 hours under nitrogen conditions, and filtered to form a transparent polyimide precursor solution. The rotational viscosity was tested to reach 4.9×10 ⁴ mPa/s, and the logarithmic viscosity was 1.6dL/g. This precursor solution is coated on the surface of the glass plate, placed in an oven, and heated at a gradient temperature from 80 to 300°C to form a transparent polyimide film.

Example 23

Add 3.2023g (0.01mol) 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl and 44g dimethylacetamide to the reaction vessel, place in an ice-water bath, and stir to dissolve. 4.5636g (0.01mol) of the dianhydride compound with the structure shown in formula (6) was added in sequence, polymerized at 5°C for 10 hours under nitrogen conditions, and filtered to form a transparent polyimide precursor solution. The rotational viscosity was tested to reach 4.6×10 ⁴ mPa/s, and the logarithmic viscosity was 1.5dL/g. Add 4.08g (0.04mol) acetic anhydride and 5.17g (0.04mol) isoquinoline to the precursor solution, react at 20°C for 2 hours, slowly pour the reaction mixture into ethanol, and a white filamentous precipitate will precipitate. Filter out and dry to obtain transparent polyimide resin. Dissolve this resin in N-methylpyrrolidone to form a 20% mass fraction solution, apply it on the surface of the glass plate, place it in an oven and heat it to 200°C to form a transparent polyimide film.

Example 24

Add 3.2023g (0.01mol) 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl, 0.12g nanosilica, and 44.4g dimethylacetamide into the reaction vessel. Warm to 6°C and stir to dissolve. Add 4.6241g (0.01mol) of the dianhydride compound with the structure shown in formula (7) in batches, perform a polymerization reaction at 25°C for 17 hours under nitrogen conditions, and filter to form a transparent polyimide precursor solution. The rotational viscosity was tested to reach 4.8×10 ⁴ mPa/s, and the logarithmic viscosity was 1.7dL/g. This precursor solution is coated on the surface of the glass plate, placed in an oven, and heated at a gradient temperature from 80 to 300°C to form a transparent polyimide film.

Example 25

Add 1.1419g (0.01mol) trans-1,4-cyclohexanediamine and 32.33g dimethylacetamide into the reaction vessel, control the temperature not to exceed 15°C, and stir to dissolve. Heat to 70°C to dissolve all the solids, cool to room temperature, add 1.2g acetic acid, stir for 15 minutes, then add 0.10g 3-aminopropyltrimethoxysilane, 0.25g tetramethoxysilane, and 36.6g N-methyl-2- Pyrrolidone, stir, and control the temperature to 6°C. Add 5.3246g (0.01mol) of the dianhydride compound with the structure shown in formula (8) in batches, perform a polymerization reaction at 20°C for 18 hours under nitrogen conditions, and filter to form a transparent polyimide precursor solution. The rotational viscosity was tested to reach 4.8×10 ⁴ mPa/s, and the logarithmic viscosity was 1.9dL/g. This precursor solution is coated on the surface of the glass plate, placed in an oven, and heated at a gradient temperature from 80°C to 320°C to form a transparent polyimide film.

Example 26

Add 3.2023g (0.01mol) 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl and 47.3g N-methyl-2-pyrrolidone to the reaction vessel, stir under an ice-water bath Dissolve. Add 5.1448g (0.01 mol) of the dianhydride compound with the structure shown in formula (9) in batches, perform a polymerization reaction at 0°C for 12 hours under nitrogen, and filter to form a transparent polyimide precursor solution. The rotational viscosity was tested to reach 4.7×10 ⁴ mPa/s, and the logarithmic viscosity was 1.7dL/g. Add 3.06g (0.03mol) acetic anhydride and 3.87g (0.03mol) isoquinoline to the precursor solution, and react at 10°C for 2 hours. The reaction mixture is coated on the surface of a glass plate and placed in an oven to heat to 250°C to form a transparent polyimide film.

Example 27

Add 1.1419g (0.01mol) trans-1,4-cyclohexanediamine and 45g N-methyl-2-pyrrolidone into the reaction vessel, control the temperature not to exceed 15°C, and stir to dissolve. Heat to 80°C to completely dissolve the solid, cool to room temperature, add 1.2g acetic acid, stir for 10 minutes, add 6.8248g (0.01mol) dianhydride compound with the structure shown in formula (10) in batches, and polymerize at 15°C under nitrogen. React for 18 hours and filter to form a transparent polyimide precursor solution. The rotational viscosity was tested to reach 3.8×10 ⁴ mPa/s, and the logarithmic viscosity was 1.4dL/g. This precursor solution is coated on the surface of the glass plate, placed in an oven, and heated at a gradient temperature from 80°C to 320°C to form a transparent polyimide film.

Example 28

Add 3.2023g (0.01mol) 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl and 50.47g dimethylacetamide into the reaction vessel, stir and dissolve in an ice-water bath. 3.4833g (0.005mol) dianhydride compound with the structure shown in formula (11) and 2.2212g (0.005mol) hexafluorodianhydride were added in sequence, polymerized at 25°C for 18h under nitrogen conditions, and filtered to form a transparent polyimide precursor solution. The rotational viscosity was tested to reach 4.6×10 ⁴ mPa/s, and the logarithmic viscosity was 1.6dL/g. Add 4.08g acetic anhydride and 3.16g pyridine to the polymerization system, and react at 10°C for 4 hours. The reaction mixture is coated on the surface of the glass plate and placed in an oven to heat to 280°C to form a transparent polyimide film.

Example 29

Add 3.2023g (0.01mol) 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl and 45.85g N-methyl-2-pyrrolidone into the reaction vessel, control the temperature to 15°C, and stir Dissolve. 3.111g (0.006mol) dianhydride compound with the structure shown in formula (12) and 1.1769g (0.004mol) biphenyl dianhydride were added in sequence, polymerized at 5°C for 24h under nitrogen conditions, and filtered to form a transparent polyimide precursor solution. The rotational viscosity was tested to reach 3.7×10 ⁴ mPa/s, and the logarithmic viscosity was 1.4dL/g. Add 7.14g (0.07mol) acetic anhydride and 5.54g (0.07mol) pyridine to the precursor solution, and react at 25°C for 3 hours. The reaction mixture was slowly poured into methanol. White filamentous precipitates precipitated. The filamentous precipitate is filtered out and dried. Obtain transparent polyimide resin. Dissolve this resin in γ-butyrolactone to form a 20% mass fraction solution, apply it on the surface of the glass plate, place it in an oven and heat it to 150°C to form a transparent polyimide film.

Example 30

Add 3.2023g (0.01mol) 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl and 44.14g dimethylacetamide to the reaction vessel, stir and dissolve in an ice-water bath. 3.699g (0.008mol) dianhydride compound with the structure shown in formula (13) and 0.888g (0.002mol) hexafluorodianhydride were added in sequence, polymerized at 25°C for 24h under nitrogen conditions, and filtered to form a transparent polyimide precursor solution. The rotational viscosity was tested to reach 3.8×10 ⁴ mPa/s, and the logarithmic viscosity was 1.4dL/g. Add 5.1g (0.05mol) acetic anhydride and 5.06g (0.05mol) triethylamine to the precursor solution, and react at 15°C for 2 hours. The reaction mixture is coated on the surface of the glass plate and placed in an oven to heat to 300°C to form a transparent polyimide film.

Example 31

3.2023g (0.01mol) 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl and 51.93g N-methyl-2-pyrrolidone were added to the reaction vessel. 5.9652g (0.01mol) of the dianhydride compound with the structure shown in formula (14) was added in batches, polymerized at 0°C for 24 hours under nitrogen, and filtered to form a transparent polyimide precursor solution. The rotational viscosity was tested to reach 4.0×10 ⁴ mPa/s, and the logarithmic viscosity was 1.4dL/g. This precursor solution is coated on the surface of the glass plate, placed in an oven, and heated at a gradient temperature from 80°C to 320°C to form a transparent polyimide film.

Example 32

Add 1.1419g (0.01mol) trans-1,4-cyclohexanediamine and 36g N-methyl-2-pyrrolidone into the reaction vessel, control the temperature to 20°C, and stir to dissolve. Heat to 70°C to completely dissolve the solid, cool to room temperature, add 1.2g acetic acid, stir for 15 minutes, add 5.1650g (0.01mol) dianhydride compound with the structure shown in formula (15) in batches, and polymerize at 15°C under nitrogen conditions React for 15 hours and filter to form a transparent polyimide precursor solution. The rotational viscosity was tested to reach 4.5×10 ⁴ mPa/s, and the logarithmic viscosity was 1.6dL/g. This precursor solution is coated on the surface of the glass plate, placed in an oven, and heated at a gradient temperature from 80°C to 300°C to form a transparent polyimide film.

Example 33

Add 3.2023g (0.01mol) 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl and 50g dimethylacetamide into the reaction vessel, control the temperature not to exceed 30°C, stir and dissolve . 5.2832g (0.01mol) of the dianhydride compound with the structure shown in formula (16) was added in sequence, polymerized at 30°C for 18 hours under nitrogen, and filtered to form a transparent polyimide precursor solution. The rotational viscosity was tested to reach 4.5×10 ⁴ mPa/s, and the logarithmic viscosity was 1.3dL/g. The precursor solution is coated on the surface of the glass plate, placed in an oven, and heated at a gradient temperature from 80°C to 200°C to form a transparent polyimide film.

The properties of the transparent polyimide films of Examples 17 to 33 were tested, and the test results are shown in Table 1.

Table 1 Performance test results of transparent polyimide films of Examples 17 to 33

Table 2 Contact angle and surface energy of transparent polyimide films of Examples 17 to 33

As can be seen from Table 1 and Table 2, the average transmittance of the transparent polyimide film prepared by the present invention at a wavelength of 380 to 780 nm (based on a film thickness of 30 μm, measured by a UV spectrometer) is not less than 88%. The thermal expansion coefficient (CTE) at 100~300℃ does not exceed 25ppm/℃, the tensile strength is >150MPa, the modulus is >2.0GPa, and the surface energy is 25~40mN/m.

The description of the above embodiments is only used to help understand the method and its core idea of the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be practiced in other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (1)

1. A transparent polyimide film, the transparent polyimide film is obtained by coating a solution of transparent polyimide on the surface of a support and carrying out an imidization reaction; The transparent polyimide is prepared according to the following method: A) Perform a polycondensation reaction between the dianhydride monomer and the diamine monomer to obtain a polyimide precursor solution; B) imidize the precursor solution of the polyimide to obtain a transparent polyimide; The diamine monomer is trans-1,4-cyclohexanediamine or 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl; When the diamine monomer is trans-1,4-cyclohexanediamine, the dianhydride monomer is a dianhydride compound with a structure shown in formula (1) or a dianhydride compound with a structure shown in formula (5). anhydride compounds; When the diamine monomer is 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl, the dianhydride monomer is a dianhydride compound having a structure shown in formula (4) , a dianhydride compound having a structure represented by formula (6), a dianhydride compound having a structure represented by formula (7), or a dianhydride compound having a structure represented by formula (9); (1);/> (4); (5);/> (6); (7);/> (9); The thickness of the transparent polyimide film is 10~250 μm; The thermal expansion coefficient of the transparent polyimide film at 100~300℃ does not exceed 23 ppm/℃, the tensile strength is ≥201 MPa, the modulus is ≥2.17 GPa, and the surface energy is 33.51~38.56 mN/m.