Compound and application thereof in polyimide

Abstract

The invention discloses a novel compound and application thereof in polyimide, the compound has a structure as shown in formula (I): # imgabs0 #, in the formula (I), R1 is selected from fluorine-substituted alkoxy-substituted biphenyl groups, R2 is selected from aromatic hydrocarbon groups, R4 is selected from carbonyl-containing groups, two R2 are the same or different, and two R4 are the same or different. Polyimide prepared from the compound has high heat resistance, high light transmittance and a low expansion coefficient, and the polyimide and a polyimide film have high transparency and still have a low linear thermal expansion coefficient at a high temperature, so that the polyimide and the polyimide film can be widely applied to various electrical and optical elements.

Description

Technical Field

[0001] The invention belongs to the field of new compounds, and in particular relates to a new compound and application thereof in polyimide. Background Art

[0002] Polyimide has excellent comprehensive properties such as chemical stability and high mechanical strength, good heat resistance and insulation performance, easy processing, and anti-puncture, and has become one of the fastest-growing special engineering plastics. Especially in recent years, with the rapid development of various emerging technologies such as flexible electronics, 5G communications, and the Internet of Things, compared with the poor transparency of metal foils, the poor flexibility of ultra-thin glass, the brittleness and easy cracking, and the low yield rate of display screens, transparent polyimide films have excellent comprehensive properties such as flexibility, thermal stability, optics, and dimensional stability, making them more and more widely concerned in the fields of flexible display technology, thin-film solar cells, and wearable devices. In particular, the designability of the molecular structure of polyimide monomers provides a variety of possibilities for improving the performance of polyimides. For example, the design and synthesis of non-conjugated monomer molecules can prevent the formation of conjugated structural units in the polymer molecular chain; the synthesis of monomer molecules with twisted or large side group structures can reduce the close stacking of the polyimide main chain, which can effectively improve the light transmittance of polyimide products. However, it cannot be ignored that it will inevitably increase its expansion rate and reduce its glass transition temperature. Therefore, in actual technology, it is necessary to comprehensively consider the mutual constraints of properties such as light transmittance, expansion rate and thermal stability in polyimide products, that is, from the perspective of molecular design principles, it is necessary to fully consider the influence of the electron affinity and spatial structure of diamine and dianhydride monomer molecules on the performance of polyimide.

[0003] In the prior art, although some fluorine-containing diamine monomers are involved and polyimide films with good thermal stability and high light transmittance are obtained, the comprehensive performance of the polyimide film still needs to be further improved. For example, how to ensure that the material has a low thermal expansion coefficient to ensure its application in the above-mentioned fields. Summary of the invention

[0004] In order to overcome the problems existing in the prior art, the present invention provides a compound and its application in polyimide. The present invention introduces the compound prepared by trifluoromethoxy group to make the polyimide film have good thermal stability, light transmittance and other properties, while still maintaining a low thermal expansion coefficient at high temperature.

[0005] One of the purposes of the present invention is to provide a compound having a structure shown in formula (I):

[0006]

[0007] Wherein, in formula (I), R 1 is selected from fluorine-substituted alkoxy-substituted biphenyl groups, R 2 Selected from aromatic hydrocarbon groups, R4 Selected from carbonyl-containing groups, two R 2 Same or different, two R 4 Same or different.

[0008] In a preferred embodiment, in formula (I), R 1 Selected from Where R 3 Selected from fluorine-substituted alkoxy groups.

[0009] In a further preferred embodiment, R 3 It is selected from trifluoro-substituted C1-C10 alkoxy groups, preferably trifluoro-substituted C1-C5 alkoxy groups, for example, trifluoro-substituted methoxy groups, trifluoro-substituted ethoxy groups, trifluoro-substituted propoxy groups, trifluoro-substituted butoxy groups, trifluoro-substituted pentyloxy groups, and the like.

[0010] In a further preferred embodiment, in formula (I), R 1 Selected from 2,2'-trifluoromethoxy substituted biphenyl groups.

[0011] Among them, R 1 Selected from

[0012] In a preferred embodiment, in formula (I), R 2 Selected from phenyl and / or substituted phenyl.

[0013] In a further preferred embodiment, R 2 One selected from the group consisting of phenyl, alkyl-substituted phenyl, and halogen-substituted phenyl, preferably one selected from the group consisting of phenyl, C1-C10 (eg, C1-C5) alkyl-substituted phenyl, fluorine-substituted phenyl, chlorine-substituted phenyl, and bromine-substituted phenyl.

[0014] In a preferred embodiment, in formula (I), R 4 Selected from Among them, the carbonyl group and R 2 connect.

[0015] The second object of the present invention is to provide a method for preparing the compound described in the first object of the present invention, comprising: (1) NH 2 -R 1 -NH 2 with NO 2 -R 2 -C(=O)Cl to obtain an intermediate of formula (II); (2) the intermediate of formula (II) is reacted in the presence of a catalyst and a reducing agent to obtain a compound of formula (I);

[0016]

[0017] Among them, NH2 -R 1 -NH 2 Medium R 1 Same as R in formula (I) 1 , NO 2 -R 2 -C(=O)Cl 2 Same as R in formula (I) 2 .

[0018] In a preferred embodiment, in step (1), the method is carried out in the presence of a basic substance.

[0019] In a further preferred embodiment, the alkaline substance is selected from at least one of triethylamine, pyridine, alkyl-substituted pyridine, N,N-diisopropylethylamine, triethylenediamine, quinoline, and isoquinoline, more preferably triethylamine.

[0020] In a further preferred embodiment, the alkaline substance and the NH 2 -R 1 -NH 2 The molar ratio of NH 2 -R 1 -NH 2 with NO 2 -R 2 The molar ratio of -C(=O)Cl is 1:(1-10), preferably 1:(2-8), for example 1:1, 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9 or 1:10.

[0021] In a preferred embodiment, the reaction in step (1) is carried out at -10 to 35°C, preferably at 0 to 30°C, for example -10°C, -5°C, 0°C, 5°C, 10°C, 15°C, 20°C, 25°C, 30°C or 35°C or for example room temperature.

[0022] In a preferred embodiment, step (1) is carried out in an organic solvent, and the organic solvent is selected from one or a mixture of two or more of ethyl acetate, dichloromethane, dimethyl sulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide and N-methylpyrrolidone in any proportion.

[0023] In a further preferred embodiment, NH 2 -R 1 -NH 2 with NO 2 -R 2The ratio of the total weight of -C(=O)Cl to the weight of the organic solvent is 1:(1.5-20), 1:(2-20), for example, 1:1.5, 1:1.8, 1:2, 1:4, 1:6, 1:8, 1:10, 1:12, 1:14, 1:16, 1:18 or 1:20.

[0024] Preferably, first configure NH 2 -R 1 -NH 2 and the dispersion of the organic solvent, NO 2 -R 2 The dispersion of -C(=O)Cl and the organic solvent are mixed and reacted.

[0025] In a preferred embodiment, in step (2), the catalyst is selected from commonly used catalysts in the art, preferably a metal carbon catalyst, more preferably at least one of a palladium carbon catalyst, a nickel carbon catalyst, and a platinum carbon catalyst; and / or the reducing agent is selected from commonly used reducing agents in the art, preferably at least one of hydrogen, hydrazine hydrate, formic acid, ammonium formate, and sodium formate, more preferably hydrazine hydrate.

[0026] In a further preferred embodiment, in step (2), the amount of the catalyst used is 1 wt% to 10 wt% of the intermediate represented by formula (II); and / or the weight ratio of the reducing agent to the intermediate represented by formula (II) is (1 to 20):1.

[0027] For example, in step (2), the amount of the catalyst used is 1wt%, 2wt%, 3wt%, 4wt%, 5wt%, 6wt%, 7wt%, 8wt%, 9wt% or 10wt% of the intermediate represented by formula (II); and / or, the weight ratio of the reducing agent to the intermediate represented by formula (II) is 1:1, 2:1, 4:1, 6:1, 8:1, 10:1, 12:1, 14:1, 16:1, 18:1 or 20:1.

[0028] In a preferred embodiment, step (2) is carried out in the presence of a solvent, and the solvent is selected from one or a mixture of two or more of ethyl acetate, dichloromethane, dimethyl sulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide, and N-methylpyrrolidone in any proportion.

[0029] In a further preferred embodiment, in step (2), the ratio of the total weight of the intermediate represented by formula (II) and the reducing agent to the weight of the solvent is 1:(2-20), preferably 1:(3-10), for example, 1:2, 1:3, 1:5, 1:6, 1:8, 1:10, 1:12, 1:14, 1:16, 1:18 or 1:20.

[0030] In a preferred embodiment, in step (2), the reaction is carried out at 20-100°C, preferably 50-70°C, for example 20°C, 30°C, 40°C, 50°C, 60°C, 70°C, 80°C, 90°C or 100°C.

[0031] The third object of the present invention is to provide the use of the compound described in the first object of the present invention or the compound obtained by the preparation method described in the second object of the present invention in polyimide.

[0032] A fourth object of the present invention is to provide a polyimide, which includes a polymerization product of a diamine compound and a dianhydride compound, wherein the diamine compound includes a diamine compound I and an optional diamine compound II, and the diamine compound I is selected from the compound described in one of the objects of the present invention or the compound obtained by the preparation method described in the second object of the present invention.

[0033] In a preferred embodiment, the dianhydride compound is selected from at least one of tetracarboxylic dianhydride compounds.

[0034] In a further preferred embodiment, the dianhydride compound is selected from at least one of the compounds represented by formula (III):

[0035]

[0036] In formula (III), A is selected from a cycloalkane group, a bicycloalkane group, an aromatic hydrocarbon group (such as a phenyl group, a biphenyl group), an aromatic ether group (such as a diphenyl group), and an aromatic ketone group (such as a benzophenone group).

[0037] In a further preferred embodiment, in formula (III), A is selected from any one of the following groups:

[0038]

[0039] In a preferred embodiment, the polyimide comprises a repeating structural unit represented by formula (IV):

[0040]

[0041] In formula (IV), R 1 , R 2 , R 4 , A has the same definition as in formula (I) and formula (III).

[0042] In a preferred embodiment, the diamine compound II is selected from other diamine compounds other than the compounds described in one of the objectives of the present invention.

[0043] In a further preferred embodiment, the diamine compound II is selected from ethylenediamine, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane, 1,12-diaminododecane, difluorobutylene diamine, 1,6-diphenyl-2,5-hexanediamine, 1,2-diaminocyclohexane, 1,3-diaminocyclohexane, 1,4-diaminocyclohexane, trans-1,4-diaminocyclohexane, 1,2-bis(2-aminoethyl)cyclohexane, 1,3-bis(2-aminoethyl)cyclohexane, 1,4-bis(2-aminoethyl)cyclohexane Cyclohexane, o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, 3,3'-p-phenylenediamine, 2-fluoro-5-methyl-1,4-phenylenediamine, 2,6-dimethoxy-1,4-phenylenediamine, 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 4,4'-aminodiphenylmethane, 2,2-bis(3-aminophenyl)propane, 2,2-bis(4-aminophenyl)propane, 2-(3-aminophenyl)-2-(4-aminophenyl)propane, 1,1-bis(3-aminophenyl)-1-phenylethane, 1,1-bis(4-aminophenyl)-1-phenylethane, 1-(3-aminophenyl)-1 1,3-bis(3-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,4-bis(3-aminophenoxy)benzene, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminobenzoyl)benzene, 1,3-bis(3-aminobenzoyl)benzene, 1,4-bis(4-aminobenzoyl)benzene, 1,4-bis(3-aminobenzoyl)benzene, 1,3-bis(3-amino-α,α-dimethylbenzyl)benzene, 1,3-bis(4-amino-α,α-dimethylbenzyl)benzene, 1,4-bis(3-amino-α,α-dimethylbenzyl)benzene, 1,4-bis(4-amino-α,α-dimethylbenzyl)benzene, 2,6-bis(3-aminophenoxy)benzene )benzylnitrile, 2,6-bis(3-aminophenoxy)pyridine, bis[4-(3-aminophenoxy)phenyl]ether, bis[4-(4-aminophenoxy)phenyl]ether, 2,2-bis[4-(3-aminophenoxy)phenyl]propane, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 1,3-bis[4-(3-aminophenoxy)benzoyl]benzene, 1,3-bis[4-(4-aminophenoxy)benzoyl]benzene, 1,4-bis[4-(3-aminophenoxy)benzoyl]benzene, 1,4-bis[4-(4-aminophenoxy)benzoyl]benzene, 1,3-bis[4-(3-aminophenoxy)-α,α-dimethylbenzyl]benzene, 1,3-Bis[4-(4-aminophenoxy)-α,α-dimethylbenzyl]benzene, 6,6'-bis(3-aminophenoxy)-3,3,3',3'-tetramethyl-1,1'-bisspiroindene, 6,6'-bis(4-aminophenoxy)-3,3,3',3'tetramethyl-1,1'-bisspiroindene, 6,6-bis(4-aminophenoxy)-3,3,3',3'-tetramethyl-1,1'-bisspiroindene, 5,2-dimethyl-4,5-pyrimidinediamine, 2-methoxy-4,5-pyrimidinediamine, 4,6-pyrimidinediamine, 2-vinyl-4,6-pyrimidinediamine, 2,5-pyrimidinediamine, 5-(4-fluorophenyl)-4,5-pyrimidinediamine, 6-(4-fluorophenyl)-2,4-pyrimidinediamine, 6 -tert-butyl-2,4-pyrimidinediamine, 6-methyl-2,4-pyrimidinediamine, 2-methyl-4,6-pyrimidinediamine, 2-ethyl-4,6-pyrimidinediamine, bis(aminomethyl) ether, bis(2-aminoethyl) ether, bis(3-aminopropyl) ether, bis[(2-aminomethoxy)ethyl] ether, bis[2-(2-aminoethoxy)ethyl] ether, bis[2-(3-aminooxy)ethyl] ether, 1,2-bis(aminomethoxy)ethane, 1,2-bis(aminoethoxy)ethane, 1,2-bis[2-(aminomethoxy)ethoxy]ethane, 1,2-bis[2-(2-aminoethoxy)ethoxy]ethane, ethylene glycol bis(3-aminopropyl) ether, diethylene glycol bis(3-aminopropyl) ether, triethylene glycol bis (3-aminopropyl) ether, bis(4-aminocyclohexyl)methane, 2,6-bis(aminomethyl)bicyclo[2.2.1]heptane, 2,5-bis(aminomethyl)bicyclo[2.2.1]heptane, 1,4-diamino-2-fluorobenzene, 1,4-diamino-2,3-difluorobenzene, 1,4-diamino-2,5-difluorobenzene, 1,4-diamino-2,6-difluorobenzene, 1,4-diamino-2,3,5-trifluorobenzene, 1,4-diamino-2,3,5,6-tetrafluorobenzene, 1,4-diamino-2-(trifluoromethyl)benzene, 1,4-diamino-2,3-bis(trifluoromethyl)benzene, 1,4-diamino-2,5-bis(trifluoromethyl)benzene, 1,4-diamino-2,6-di( 1,4-diamino-2,3,5-tris(trifluoromethyl)benzene, 1,4-diamino-2,3,5,6-tetra(trifluoromethyl)benzene, 2-fluorobenzidine, 3-fluorobenzidine, 2,3-difluorobenzidine, 2,5-difluorobenzidine, 2,6-difluorobenzidine, 2,2'-difluorobenzidine, 3,3'-difluorobenzidine, 2,3'-difluorobenzidine, 2,2',3-trifluorobenzidine, 2,3,3'-trifluorobenzidine, 2,2',5-trifluorobenzidine, 2,2',6-trifluorobenzidine, 2,3',5-trifluorobenzidine, 2,3',6-trifluorobenzidine, 2,2',3,3'-tetrafluorobenzidine, 2,2',5,5'-Tetrafluorobenzidine, 2,2',6,6'-tetrafluorobenzidine, 2,2'3,3',6,6'-hexafluorobenzidine, 2,2',3,3',5,5',6,6'-octafluorobenzidine, 2-(trifluoromethyl)benzidine, 3-(trifluoromethyl)benzidine, 2,3-bis(trifluoromethyl)benzidine, 2,5-bis(trifluoromethyl)benzidine, 2,6-bis(trifluoromethyl)benzidine, 2,3'-bis(trifluoromethyl)benzidine, 2,2',3-tris(trifluoromethyl)benzidine, 2,3,3'-tris(trifluoromethyl)benzidine, 2,2',5-tris(trifluoromethyl)benzidine, 2,2', At least one of 6-tris(trifluoromethyl)benzidine, 2,3',5-tris(trifluoromethyl)benzidine, 2,3',6-tris(trifluoromethyl)benzidine, 2,2',3,3'-tetrakis(trifluoromethyl)benzidine, 2,2',5,5'-tetrakis(trifluoromethyl)benzidine, 2,2',6,6'-tetrakis(trifluoromethyl)benzidine, (1S,2S)-1,2-di(4-fluorophenyl)-1,2-ethylenediamine, (1S,2S)-1,2-di-1-naphthyl-1,2-ethylenediamine, 1,2-di(4-bromophenyl)ethylenediamine, and (R,R)-1,2-bis(4-cyanophenyl)-1,2-ethylenediamine.

[0044] In a preferred embodiment, based on 100 mol% of the total amount of the diamine compound I and the optional diamine compound II, the amount of the diamine compound I is more than 20 mol%, preferably more than 60 mol%, for example, 20 mol%, 30 mol%, 40 mol%, 50 mol%, 60 mol%, 70 mol%, 80 mol%, 90 mol% or 100 mol%.

[0045] The preparation method of the polyimide of the present invention is not particularly limited, and a known method can be used to obtain a polyimide precursor, polyamic acid, and then imidization is performed by a thermal imidization method or a chemical imidization method to obtain the polyimide. The thermal imidization method is preferred in the present invention.

[0046] Preferably, the diamine compound and the dianhydride compound can be first subjected to polycondensation reaction to obtain polyamic acid, and then the polyamic acid can be obtained by thermal imidization. Specifically, the dianhydride compound is slowly added to an organic solvent containing the diamine compound, and stirred at 0-20°C, preferably at 0-10°C for 0.5-12 hours to obtain polyamic acid, and then the solvent is removed at 30-200°C (preferably 40-150°C), and then the temperature is gradually raised to the final temperature of 220-350°C for thermal imidization reaction (during the heating process, the temperature is kept at 100±20°C for 0.5-2h, the temperature is kept at 200±20°C for 0.5-2h, and the temperature is kept at the final temperature for 0.5-2h), and the polyimide is obtained after dehydration and ring closure.

[0047] In a preferred embodiment, the molar ratio of the diamine compound to the dianhydride compound is 1:(1-1.1), preferably 1:(1-1.05), more preferably 1:(1.002-1.008), for example, 1:1, 1:1.002, 1:1.003, 1:1.004, 1:1.005, 1:1.006, 1:1.007, 1:1.008, 1:1.01, 1:1.02, 1:1.04, 1:1.06, 1:1.08 or 1:1.1.

[0048] In a preferred embodiment, the solvent used in the polymerization reaction is not particularly limited, as long as it can uniformly dissolve the monomer diamine, tetracarboxylic dianhydride and the generated polyamic acid. Available solvents include: amide solvents such as dimethylformamide, dimethylacetamide and N-methylpyrrolidone, or ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone and cyclohexanone, or ether solvents such as tetrahydrofuran, 1,3-dioxolane and 1,4-dioxane. These solvents can be used alone or in combination of two or more in any ratio.

[0049] In a preferred embodiment, the solid content in the system during polymerization is 5 to 40 wt%, preferably 15 to 30 wt%, more preferably 20 to 25 wt%, for example 5 wt%, 10 wt%, 15 wt%, 20 wt%, 25 wt%, 30 wt%, 35 wt% or 40 wt%.

[0050] The fifth object of the present invention is to provide the use of the polyimide described in the fourth object of the present invention in a film.

[0051] The sixth object of the present invention is to provide a polyimide film, which is obtained by using the polyimide described in the fourth object of the present invention.

[0052] It can be prepared by the following method, i.e., subjecting the diamine compound to a dianhydride compound for a condensation reaction to obtain polyamic acid (preferably, slowly adding the dianhydride compound to an organic solvent containing the diamine compound, and stirring at 0-20°C, preferably at 0-10°C for 0.5-12 hours, to obtain polyamic acid), coating it on a substrate for imidization and dehydration, to obtain the polyimide film.

[0053] Preferably, the imidization dehydration is carried out as follows: removing the solvent at 80-200° C. and carrying out a thermal imidization reaction at 220-350° C.;

[0054] More preferably, the imidization dehydration is carried out as follows: (a) after coating the polyamic acid, heat it to 80-100°C at a rate of 1-3°C / min, keep it at 80-100°C for 1-2h, then continue to heat it to 180-200°C at a rate of 1-3°C / min, and keep it at 180-200°C for 1-2h; (b) react at 220-260°C for 1-2h, continue to heat it to 280-350°C and react for 0.5-1.5h.

[0055] Among them, the substrates that can be selected to be coated with the polyamic acid solution include glass substrates, metal substrates or metal belts such as SUS, plastic films such as polyethylene terephthalate, polycarbonate, polyacrylate, polyethylene naphthalate and triacetyl cellulose, etc., but are not limited thereto.

[0056] The present invention provides a polyimide and a polyimide film having excellent properties such as low thermal expansion coefficient, high light transmittance, and high heat resistance. Since the polyimide and the polyimide film have high transparency and still have a low linear thermal expansion coefficient at high temperatures, they can be widely used in various electrical and optical components.

[0057] The seventh object of the present invention is to provide the use of the polyimide described in the fourth object of the present invention and the polyimide film described in the sixth object of the present invention in substrates, color filters, printed materials, luminescent materials, electronic devices, flexible display screens, liquid crystal display devices, electronic paper, and optical films.

[0058] The polyimide and polyimide film of the present invention overcome the problem that it is difficult to achieve both high light transmittance and low expansion coefficient in traditional polyimide films, and have a wide range of applications, such as substrates, color filters, printed materials, luminescent materials, electronic devices, flexible display screens, liquid crystal display devices, electronic paper, optical films and other fields and products.

[0059] The endpoints and any values ​​of the scope disclosed in the present invention are not limited to the precise scope or value, and these scopes or values ​​should be understood to include values ​​close to these scopes or values. For numerical ranges, the endpoint values ​​of each scope, the endpoint values ​​of each scope and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article. Hereinafter, in principle, each technical solution can be combined with each other to obtain a new technical solution, which should also be considered as specifically disclosed in this article.

[0060] Compared with the prior art, the present invention has the following beneficial effects:

[0061] The invention provides a novel compound which can be used for preparing polyimide.

[0062] The polyimide has a lower linear thermal expansion coefficient at high temperature and has good light transmittance, and thus can be widely used in various electrical and optical components. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] Figure 1 The hydrogen nuclear magnetic resonance spectrum of N,N'-(2,2'-bis(trifluoromethoxy)-[1,1-biphenyl]-4,4'-diamino)bis(4-aminobenzamide) prepared in Example 1 of the present invention is shown. DETAILED DESCRIPTION

[0064] The present invention is described in detail below in conjunction with specific embodiments. It is necessary to point out that the following embodiments are only used to further illustrate the present invention and cannot be understood as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made to the present invention by those skilled in the art based on the contents of the present invention still fall within the scope of protection of the present invention.

[0065] It should also be noted that the various specific technical features described in the following specific embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0066] In addition, the various embodiments of the present invention may be arbitrarily combined as long as they do not violate the concept of the present invention. The technical solutions thus formed belong to part of the original disclosure of this specification and also fall within the protection scope of the present invention.

[0067] The raw materials used in the examples and comparative examples, unless otherwise specified, are disclosed in the prior art, for example, they can be directly purchased or prepared according to the preparation methods disclosed in the prior art.

[0068] Raw materials and product abbreviations:

[0069] 2,2'-Bis(trifluoromethoxy)-biphenyl-4,4'-diamine: TFMOB, purchased from Tianjin Kangyuan Boao Technology Co., Ltd.;

[0070] N,N'-(2,2'-bis(trifluoromethoxy)-[1,1-biphenyl]-4,4'-diamino)bis(4-nitrobenzamide): NB-TFMOB;

[0071] N,N'-(2,2'-bis(trifluoromethoxy)-[1,1-biphenyl]-4,4'-diamino)bis(4-aminobenzamide): AB-TFMOB;

[0072] N,N'-(2,2'-bis(trifluoromethoxy)-[1,1-biphenyl]-4,4'-diamino)bis(2-fluoro-4-aminobenzamide): FAB-TFMOB;

[0073] N,N'-(2,2'-bis(trifluoromethoxy)-[1,1-biphenyl]-4,4'-diamino)bis(2-methyl-4-aminobenzamide): MAB-TFMOB;

[0074] 2,2'-Bis(trifluoromethyl)-biphenyl-4,4'-diamine: TFMB, purchased from Tianjin Zotye Materials Technology Co., Ltd.;

[0075] N,N'-(2,2'-bis(trifluoromethyl)-[1,1-biphenyl]-4,4'-diamino)bis(4-aminobenzamide): AB-TFMB was purchased from Tianjin Kangyuan Boao Technology Co., Ltd.

[0076] 2-Fluoro-4-nitrobenzoyl chloride was purchased from Tianjin Kangyuan Boao Technology Co., Ltd.;

[0077] 2-Methyl-4-nitrobenzoyl chloride was purchased from Tianjin Kangyuan Boao Technology Co., Ltd.;

[0078] 1,2,4,5-cyclohexanetetracarboxylic dianhydride was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd., 1,2,3,4-cyclobutanetetracarboxylic dianhydride was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd., 1,2,3,4-cyclopentanetetracarboxylic dianhydride was purchased from Beijing Bailingwei Technology Co., Ltd., bicyclo[2,2,1]heptane-2,3,5,6-tetracarboxylic dianhydride was purchased from Zhengzhou Alpha Chemical Co., Ltd., bicyclo[2,2,2]octane-2,3,5,6-tetracarboxylic dianhydride was purchased from Henan Alpha Chemical Co., Ltd. Co., Ltd. (98%), decahydrobiphenyl-3,3',4,4'-tetracarboxylic dianhydride was purchased from Tianjin Kangyuan Bo'ao Technology Co., Ltd., pyromellitic dianhydride was purchased from Tianjin Jiangtian Chemical Technology Co., Ltd., 3,3',4,4'-biphenyltetracarboxylic dianhydride was purchased from Tianjin Zotye Material Technology Co., Ltd., 3,3',4,4'-benzophenonetetracarboxylic dianhydride was purchased from Shanghai MacLean Biochemical Technology Co., Ltd., and 2,3,3',4'-diphenyl ether tetracarboxylic dianhydride was purchased from Tianjin Zotye Material Technology Co., Ltd.

[0079] Example 1

[0080] Synthesis of the compound represented by formula (I):

[0081] Synthesis of AB-TFMOB precursor NB-TFMOB:

[0082] At room temperature, 28.1784g (80mmol) TFMOB was dissolved in 90ml anhydrous ethyl acetate, and 22.4mL (160mmol) triethylamine was added by syringe. After complete dissolution, it was moved to an ice water bath, and 30.619g (165mmol) p-nitrobenzoyl chloride ethyl acetate (70mL) solution was slowly added dropwise (drop rate was 1d / s [drops / second]). After the addition was completed, the reaction was stirred for 12h, and the reaction endpoint was confirmed by thin layer chromatography. After the reaction was completed, a yellow suspension was obtained, which was extracted with deionized water, washed with sodium carbonate solution, and beaten to obtain a solid powder, which was dried at 40°C for 4h to obtain 46.323g of AB-TFMOB precursor nitro compound NB-TFMOB, with a yield of 89%.

[0083] Synthesis of AB-TFMOB:

[0084] Under an ice-water bath, 6.505 g (10 mmol) NB-TFMOB and 0.6505 g Pd / C were dissolved in 60 ml ethyl acetate, and 10 mL hydrazine hydrate (1 d / s) was slowly added dropwise. After the addition was completed, the temperature was raised to 60 ° C for reaction for 5 h, and the reaction endpoint was confirmed by thin layer chromatography. After the reaction was completed, the filtrate was filtered, and the obtained filtrate was dropped into water to produce a white precipitate. After stirring for 6 h, the precipitate was separated and recrystallized using a mixed solvent of ethyl acetate (60 ml) and petroleum ether (30 ml), and dried at 40 ° C under vacuum for 12 h to obtain 5.469 g of the product AB-TFMOB with a yield of 92.6%.

[0085] Polyimide film:

[0086] Under nitrogen atmosphere, 2.952 g (5 mmol) of AB-TFMOB was dissolved in 8 mL of N, N-dimethylacetamide, and 1.1231 g (5.01 mmol) of 1,2,4,5-cyclohexanetetracarboxylic dianhydride was slowly added while maintaining the temperature at 0°C. 6 mL of N, N-dimethylacetamide was added three times within half an hour of reaction, and the solid content of the obtained system was 24 wt%. After stirring for 8 hours, the reaction solution was transferred into a vacuum oven for degassing at room temperature to obtain a uniform polyamic acid glue solution (PAA glue solution). The PAA glue solution was cast on a glass plate to form a film, and then transferred to a muffle furnace for thermal imidization. The solvent was removed by keeping it at 40°C for 100 minutes under vacuum conditions, and then the temperature was raised to 100°C at 1°C / min, kept at 100°C for 1 hour, then raised to 200°C at 1°C / min, kept at 200°C for 1 hour, then raised to 300°C at 1°C / min, kept at 300°C for 1 hour, and the thermal imidization was completed to obtain a polyimide film with a thickness of 20 μm. The glass transition temperature of the polyimide film is above 350°C, which meets the application requirements.

[0087] Example 2

[0088] Under the condition of 4°C and nitrogen atmosphere, 2.952g (5mmol) AB-TFMOB was dissolved in 10mL N,N-dimethylacetamide, and 0.9825g (5.01mmol) 1,2,3,4-cyclobutanetetracarboxylic dianhydride was slowly added; 6mL of N,N-dimethylacetamide was added three times within half an hour of reaction, and the solid content of the obtained system was 21wt%; after stirring for 8h, the reaction solution was transferred into a vacuum oven for degassing at room temperature to obtain a uniform polyamic acid glue solution (PAA glue solution). The PAA glue solution was cast on a glass plate to form a film, and then transferred to a muffle furnace for thermal imidization. The solvent was removed by keeping it at 40°C for 100 minutes under vacuum conditions, and then the temperature was raised to 100°C at 1°C / min, kept at 100°C for 1 hour, then raised to 200°C at 1°C / min, kept at 200°C for 1 hour, then raised to 300°C at 1°C / min, kept at 300°C for 1 hour, and the thermal imidization was completed to obtain a polyimide film with a thickness of 20 μm. The glass transition temperature of the polyimide film is above 350°C, which meets the application requirements.

[0089] Example 3

[0090] Keeping 0℃ and nitrogen atmosphere conditions, 2.952g (5mmol) AB-TFMOB was dissolved in 10mL N,N-dimethylacetamide, and 1.0528g (5.01mmol) 1,2,3,4-cyclopentanetetracarboxylic dianhydride was slowly added; 6mL of N,N-dimethylacetamide was added three times within half an hour of reaction, and the solid content of the obtained system was 21wt%; after stirring the reaction for 8h, the reaction solution was transferred into a vacuum oven for degassing at room temperature to obtain a uniform polyamic acid glue solution (PAA glue solution). The PAA glue solution was cast on a glass plate to form a film, and then transferred to a muffle furnace for thermal imidization. The solvent was removed at 40°C for 100 minutes under vacuum conditions, and then the temperature was raised to 100°C at 2°C / min, and maintained at 100°C for 1 hour. The temperature was then raised to 200°C at 2°C / min, and maintained at 200°C for 1 hour. The temperature was then raised to 300°C at 2°C / min, and maintained at 300°C for 1 hour. The thermal imidization was completed to obtain a polyimide film with a thickness of 15 μm. The glass transition temperature of the polyimide film is above 350°C, which meets the application requirements.

[0091] Example 4

[0092] Keeping 0℃ and nitrogen atmosphere, 2.952g (5mmol) AB-TFMOB was dissolved in 10mL N,N-dimethylacetamide, and 1.187g (5.03mmol) bicyclo[2,2,1]heptane-2,3,5,6-tetracarboxylic dianhydride was slowly added; 6mL of N,N-dimethylacetamide was added three times within half an hour of reaction, and the solid content of the obtained system was 22wt%; after stirring the reaction for 8h, the reaction solution was transferred into a vacuum oven for degassing at room temperature to obtain a uniform polyamic acid glue solution (PAA glue solution). The PAA glue solution was cast on a glass plate to form a film, and then transferred to a muffle furnace for thermal imidization. The solvent was removed at 40°C for 100 minutes under vacuum conditions, and then the temperature was raised to 100°C at 1°C / min, and maintained at 100°C for 1 hour. The temperature was then raised to 200°C at 1°C / min, and maintained at 200°C for 1 hour. The temperature was then raised to 300°C at 1°C / min, and maintained at 300°C for 1 hour. The thermal imidization was completed to obtain a polyimide film with a thickness of 15 μm. The glass transition temperature of the polyimide film is above 350°C, which meets the application requirements.

[0093] Example 5

[0094] Under the condition of maintaining 0℃ and nitrogen atmosphere, 2.952g (5mmol) AB-TFMOB was dissolved in 10mL N,N-dimethylacetamide, and 1.2535g (5.01mmol) bicyclo[2,2,2]octane-2,3,5,6-tetracarboxylic dianhydride was slowly added; 8mL of N,N-dimethylacetamide was added three times within half an hour of reaction, and the solid content of the obtained system was 20wt%; after stirring the reaction for 8h, the reaction solution was transferred into a vacuum oven for degassing at room temperature to obtain a uniform polyamic acid glue solution (PAA glue solution). The PAA glue solution was cast on a glass plate to form a film, and then transferred to a muffle furnace for thermal imidization. The solvent was removed at 40°C for 100 minutes under vacuum conditions, and then the temperature was raised to 100°C at 3°C / min, and maintained at 100°C for 1 hour. The temperature was then raised to 200°C at 3°C / min, and maintained at 200°C for 1 hour. The temperature was then raised to 300°C at 3°C / min, and maintained at 300°C for 1 hour. The thermal imidization was completed to obtain a polyimide film with a thickness of 18 μm. The glass transition temperature of the polyimide film is above 350°C, which meets the application requirements.

[0095] Example 6

[0096] Keeping 0℃ and nitrogen atmosphere, 2.362g (4mmol) AB-TFMOB was dissolved in 8mL N,N-dimethylacetamide, and 1.231g (4.02mmol) decahydrobiphenyl-3,3',4,4'-tetracarboxylic dianhydride was slowly added; 6mL of N,N-dimethylacetamide was added three times within half an hour of reaction, and the solid content of the obtained system was 22wt%; after stirring the reaction for 8h, the reaction solution was transferred into a vacuum oven for degassing at room temperature to obtain a uniform polyamic acid glue solution (PAA glue solution). The PAA glue solution was cast on a glass plate to form a film, and then transferred to a muffle furnace for thermal imidization. The solvent was removed at 40°C for 100 minutes under vacuum conditions, and then the temperature was raised to 100°C at 3°C / min, and maintained at 100°C for 1 hour. The temperature was then raised to 200°C at 3°C / min, and maintained at 200°C for 1 hour. The temperature was then raised to 300°C at 3°C / min, and maintained at 300°C for 1 hour. The thermal imidization was completed to obtain a polyimide film with a thickness of 18 μm. The glass transition temperature of the polyimide film is above 350°C, which meets the application requirements.

[0097] Example 7

[0098] Under the condition of 4°C and nitrogen atmosphere, 2.952g (5mmol) AB-TFMOB was dissolved in 10mL N,N-dimethylacetamide, and 1.0928g (5.01mmol) pyromellitic anhydride was slowly added; 6mL of N,N-dimethylacetamide was added three times within half an hour of reaction, and the solid content of the obtained system was 21wt%; after stirring the reaction for 8h, the reaction solution was transferred into a vacuum oven for degassing at room temperature to obtain a uniform polyamic acid glue solution (PAA glue solution). The PAA glue solution was cast on a glass plate to form a film, and then transferred to a muffle furnace for thermal imidization. The solvent was removed by keeping it at 40°C for 100 minutes under vacuum conditions, and then the temperature was raised to 100°C at 1°C / min, kept at 100°C for 1 hour, then raised to 200°C at 1°C / min, kept at 200°C for 1 hour, then raised to 300°C at 1°C / min, kept at 300°C for 1 hour, and the thermal imidization was completed to obtain a polyimide film with a thickness of 20 μm. The glass transition temperature of the polyimide film is above 350°C, which meets the application requirements.

[0099] Example 8

[0100] Under the condition of maintaining 4°C and nitrogen atmosphere, 2.952g (5mmol) AB-TFMOB was dissolved in 10mL N,N-dimethylacetamide, and 1.474g (5.01mmol) 3,3',4,4'-biphenyltetracarboxylic dianhydride was slowly added; 6mL of N,N-dimethylacetamide was added three times within half an hour of reaction, and the solid content of the obtained system was 23wt%; after stirring the reaction for 8h, the reaction solution was transferred into a vacuum oven for degassing at room temperature to obtain a uniform polyamic acid glue solution (PAA glue solution). The PAA glue solution was cast on a glass plate to form a film, and then transferred to a muffle furnace for thermal imidization. The solvent was removed by keeping it at 40°C for 100 minutes under vacuum conditions, and then the temperature was raised to 100°C at 1°C / min, kept at 100°C for 1 hour, then raised to 200°C at 1°C / min, kept at 200°C for 1 hour, then raised to 300°C at 1°C / min, kept at 300°C for 1 hour, and the thermal imidization was completed to obtain a polyimide film with a thickness of 20 μm. The glass transition temperature of the polyimide film is above 350°C, which meets the application requirements.

[0101] Example 9

[0102] Under the condition of maintaining 4°C and nitrogen atmosphere, 2.952g (5mmol) AB-TFMOB was dissolved in 10mL N,N-dimethylacetamide, and 1.6144g (5.01mmol) 3,3',4,4'-dibenzophenonetetracarboxylic dianhydride was slowly added; 8mL of N,N-dimethylacetamide was added three times within half an hour of reaction, and the solid content of the obtained system was 21wt%; after stirring the reaction for 8h, the reaction solution was transferred into a vacuum oven for degassing at room temperature to obtain a uniform polyamic acid glue solution (PAA glue solution). The PAA glue solution was cast on a glass plate to form a film, and then transferred to a muffle furnace for thermal imidization. The solvent was removed by keeping it at 40°C for 100 minutes under vacuum conditions, and then the temperature was raised to 100°C at 1°C / min, kept at 100°C for 1 hour, then raised to 200°C at 1°C / min, kept at 200°C for 1 hour, then raised to 300°C at 1°C / min, kept at 300°C for 1 hour, and the thermal imidization was completed to obtain a polyimide film with a thickness of 20 μm. The glass transition temperature of the polyimide film is above 350°C, which meets the application requirements.

[0103] Example 10

[0104] Under the condition of maintaining 4°C and nitrogen atmosphere, 2.952g (5mmol) AB-TFMOB was dissolved in 10mL N,N-dimethylacetamide, and 1.5542g (5.01mmol) 2,3,3',4'-diphenyl ether tetracarboxylic dianhydride was slowly added; 8mL of N,N-dimethylacetamide was added three times within half an hour of reaction, and the solid content of the obtained system was 21wt%; after stirring the reaction for 8h, the reaction solution was transferred into a vacuum oven for degassing at room temperature to obtain a uniform polyamic acid glue solution (PAA glue solution). The PAA glue solution was cast on a glass plate to form a film, and then transferred to a muffle furnace for thermal imidization. The solvent was removed by keeping it at 40°C for 100 min under vacuum conditions, and then the temperature was increased to 100°C at 1°C / min, maintained at 100°C for 1 h, then increased to 200°C at 1°C / min, maintained at 200°C for 1 h, then increased to 300°C at 1°C / min, maintained at 300°C for 1 h. The thermal imidization was completed to obtain a polyamic acid film with a thickness of 20 μm.

[0105] Embodiment 11

[0106] Keeping 4 ℃ and nitrogen atmosphere conditions, 2.0664g (3.5mmol) AB-TFMOB and 0.3003g (1.5mmol) 4,4'-diaminodiphenyl ether were dissolved in 8mL N,N-dimethylacetamide, and 1.1231g (5.01mmol) 1,2,4,5-cyclohexanetetracarboxylic dianhydride was slowly added; N,N-dimethylacetamide was added three times within half an hour of reaction for a total of 6mL, and the solid content of the obtained system was 21wt%; after stirring the reaction for 8h, the reaction solution was transferred into a vacuum oven for degassing at room temperature to obtain a uniform polyamic acid glue solution (PAA glue solution). The PAA glue solution was cast on a glass plate to form a film, and then transferred to a muffle furnace for thermal imidization. The solvent was removed at 40°C for 100 minutes under vacuum conditions, and then the temperature was raised to 100°C at 1°C / min, and maintained at 100°C for 1 hour. The temperature was then raised to 200°C at 1°C / min, and maintained at 200°C for 1 hour. The temperature was then raised to 300°C at 1°C / min, and maintained at 300°C for 1 hour. The thermal imidization was completed to obtain a polyimide film with a thickness of 15 μm. The glass transition temperature of the polyimide film is above 350°C, which meets the application requirements.

[0107] Example 12

[0108] Keeping 4 ℃ and nitrogen atmosphere conditions, 0.8856g (1.5mmol) AB-TFMOB and 0.7008g (3.5mmol) 4,4'-diaminodiphenyl ether were dissolved in 5mL N,N-dimethylacetamide, and 1.1231g (5.01mmol) 1,2,4,5-cyclohexanetetracarboxylic dianhydride was slowly added; N,N-dimethylacetamide was added three times within half an hour of reaction for a total of 6mL, and the solid content of the obtained system was 21wt%; after stirring the reaction for 8h, the reaction solution was transferred into a vacuum oven for degassing at room temperature to obtain a uniform polyamic acid glue solution (PAA glue solution). The PAA glue solution was cast on a glass plate to form a film, and then transferred to a muffle furnace for thermal imidization. The solvent was removed at 40°C for 100 minutes under vacuum conditions, and then the temperature was raised to 100°C at 1°C / min, and maintained at 100°C for 1 hour. The temperature was then raised to 200°C at 1°C / min, and maintained at 200°C for 1 hour. The temperature was then raised to 300°C at 1°C / min, and maintained at 300°C for 1 hour. The thermal imidization was completed to obtain a polyimide film with a thickness of 15 μm. The glass transition temperature of the polyimide film is above 350°C, which meets the application requirements.

[0109] Example 13

[0110] Under the condition of 4°C and nitrogen atmosphere, 2.0664g (3.5mmol) AB-TFMOB and 0.3003g (1.5mmol) 4,4'-diaminodiphenyl ether were dissolved in 8mL N,N-dimethylacetamide, and 1.5342g (5.01mmol) decahydrobiphenyl-3,3',4,4'-tetracarboxylic dianhydride was slowly added; 6mL of N,N-dimethylacetamide was added three times within half an hour of reaction, and the solid content of the obtained system was 23wt%; after stirring the reaction for 8h, the reaction solution was transferred into a vacuum oven for degassing at room temperature to obtain a uniform polyamic acid glue solution (PAA glue solution). The PAA glue solution was cast on a glass plate to form a film, and then transferred to a muffle furnace for thermal imidization. The solvent was removed at 40°C for 100 minutes under vacuum conditions, and then the temperature was raised to 100°C at 1°C / min, and maintained at 100°C for 1 hour. The temperature was then raised to 200°C at 1°C / min, and maintained at 200°C for 1 hour. The temperature was then raised to 300°C at 1°C / min, and maintained at 300°C for 1 hour. The thermal imidization was completed to obtain a polyimide film with a thickness of 15 μm. The glass transition temperature of the polyimide film is above 350°C, which meets the application requirements.

[0111] Embodiment 14

[0112] Keeping 4 ℃ and nitrogen atmosphere conditions, 0.8856g (1.5mmol) AB-TFMOB and 0.7008g (3.5mmol) 4,4'-diaminodiphenyl ether were dissolved in 6mL N,N-dimethylacetamide, and 1.5342g (5.01mmol) decahydrobiphenyl-3,3',4,4'-tetracarboxylic dianhydride was slowly added; N,N-dimethylacetamide was added three times within half an hour of reaction for a total of 6mL, and the solid content of the obtained system was 22wt%; after stirring the reaction for 8h, the reaction solution was transferred into a vacuum oven for degassing at room temperature to obtain a uniform polyamic acid glue solution (PAA glue solution). The PAA glue solution was cast on a glass plate to form a film, and then transferred to a muffle furnace for thermal imidization. The solvent was removed at 40°C for 100 minutes under vacuum conditions, and then the temperature was raised to 100°C at 1°C / min, and maintained at 100°C for 1 hour. The temperature was then raised to 200°C at 1°C / min, and maintained at 200°C for 1 hour. The temperature was then raised to 300°C at 1°C / min, and maintained at 300°C for 1 hour. The thermal imidization was completed to obtain a polyimide film with a thickness of 15 μm. The glass transition temperature of the polyimide film is above 350°C, which meets the application requirements.

[0113] Embodiment 15

[0114] Synthesis of the compound represented by formula (I):

[0115] Synthesis of FAB-TFMOB precursor FNB-TFMOB:

[0116] At room temperature, 7.0446g (20mmol) TFMOB was dissolved in 25ml anhydrous ethyl acetate, and 5.6mL (40mmol) triethylamine was added by syringe. After complete dissolution, it was moved to an ice water bath, and 9.16g (45mmol) 2-fluoro-4-nitrobenzoyl chloride in ethyl acetate (20mL) solution was slowly added dropwise (drop rate was 1d / s [drops / second]). After the addition was completed, the reaction was stirred for 12h, and the reaction endpoint was confirmed by thin layer chromatography. After the reaction was completed, a yellow suspension was obtained, which was extracted with deionized water, washed with sodium carbonate solution, and beaten to obtain a solid powder, which was dried at 40°C for 4h to obtain 12.043 g of FAB-TFMOB precursor nitro compound FNB-TFMOB, with a yield of 87.7%.

[0117] Synthesis of FAB-TFMOB:

[0118] Under an ice-water bath, 6.866g (10mmol) FNB-TFMOB and 0.549g Pd / C were dissolved in 60ml ethyl acetate, and 10mL hydrazine hydrate (1d / s) was slowly added dropwise. After the addition was completed, the temperature was raised to 65°C for reaction for 5h, and the reaction endpoint was confirmed by thin layer chromatography. After the reaction was completed, the mixture was filtered, and the filtrate was dropped into water to produce a white precipitate. After stirring for 6h, the precipitate was separated and recrystallized using a mixed solvent of ethyl acetate (60ml) and petroleum ether (30ml), and dried at 40°C under vacuum for 12h to obtain 5.733g of the product FAB-TFMOB with a yield of 91.5%.

[0119] Polyimide film:

[0120] Under nitrogen conditions, 3.133 g (5 mmol) of FAB-TFMOB was dissolved in 10 mL of N, N-dimethylacetamide, and 1.1231 g (5.01 mmol) of 1,2,4,5-cyclohexanetetracarboxylic dianhydride was slowly added while maintaining 0°C. Within half an hour of reaction, 6 mL of N, N-dimethylacetamide was added three times, and the solid content of the obtained system was 22 wt%. After stirring the reaction for 8 hours, the reaction solution was transferred into a vacuum oven for degassing at room temperature to obtain a uniform polyamic acid glue solution (PAA glue solution). The PAA glue solution was cast on a glass plate to form a film, and then transferred to a muffle furnace for thermal imidization. The solvent was removed by keeping it at 40°C for 100 minutes under vacuum conditions, and then the temperature was raised to 100°C at 1°C / min, kept at 100°C for 1 hour, then raised to 200°C at 1°C / min, kept at 200°C for 1 hour, then raised to 300°C at 1°C / min, kept at 300°C for 1 hour, and the thermal imidization was completed to obtain a polyimide film with a thickness of 20 μm. The glass transition temperature of the polyimide film is above 350°C, which meets the application requirements.

[0121] Example 16

[0122] Synthesis of the compound represented by formula (I):

[0123] Synthesis of MAB-TFMOB precursor MNB-TFMOB:

[0124] At room temperature, 10.567g (30mmol) TFMOB was dissolved in 40ml anhydrous ethyl acetate, and 8.4mL (60mmol) triethylamine was added by syringe. After complete dissolution, it was moved to an ice water bath, and 13.17g (66mmol) 3-methyl-4-nitrobenzoyl chloride in ethyl acetate (40mL) solution was slowly added dropwise (drop rate was 1d / s [drops / second]). After the addition was completed, the reaction was stirred for 10h, and the reaction endpoint was confirmed by thin layer chromatography. After the reaction was completed, a yellow suspension was obtained, which was extracted with deionized water, washed with sodium carbonate solution, and beaten to obtain a solid powder, which was dried at 40°C for 4h to obtain 18.343 g of the MAB-TFMOB precursor nitro compound MNB-TFMOB, with a yield of 90.1%.

[0125] Synthesis of MAB-TFMOB:

[0126] Under an ice-water bath, 5.429 g (8 mmol) of MNB-TFMOB and 0.322 g of Pd / C were dissolved in 55 ml of ethyl acetate, and 8 mL of hydrazine hydrate (1 d / s) was slowly added dropwise. After the addition was completed, the temperature was raised to 65 ° C for reaction for 5 h, and the reaction endpoint was confirmed by thin layer chromatography. After the reaction was completed, the filtrate was filtered, and the obtained filtrate was dropped into water to produce a white precipitate. After stirring for 6 h, the precipitate was separated and recrystallized using a mixed solvent of ethyl acetate (60 ml) and petroleum ether (30 ml), and dried at 40 ° C under vacuum for 12 h to obtain 4.64 g of the product MAB-TFMOB with a yield of 93.7%.

[0127] Polyimide film:

[0128] Under nitrogen conditions, 2.4744 g (4 mmol) of MAB-TFMOB was dissolved in 8 mL of N, N-dimethylacetamide, and 0.8989 g (4.01 mmol) of 1,2,4,5-cyclohexanetetracarboxylic dianhydride was slowly added while maintaining 0°C. 6 mL of N, N-dimethylacetamide was added three times within half an hour of reaction, and the solid content of the obtained system was 20 wt%. After stirring the reaction for 8 hours, the reaction solution was transferred into a vacuum oven for degassing at room temperature to obtain a uniform polyamic acid glue solution (PAA glue solution). The PAA glue solution was cast on a glass plate to form a film, and then transferred to a muffle furnace for thermal imidization. The solvent was removed by keeping it at 40°C for 100 minutes under vacuum conditions, and then the temperature was raised to 100°C at 1°C / min, kept at 100°C for 1 hour, then raised to 200°C at 1°C / min, kept at 200°C for 1 hour, then raised to 300°C at 1°C / min, kept at 300°C for 1 hour, and the thermal imidization was completed to obtain a polyimide film with a thickness of 20 μm. The glass transition temperature of the polyimide film is above 350°C, which meets the application requirements.

[0129] Comparative Example 1

[0130] A polyimide film, the preparation method of which comprises:

[0131] In an ice-water bath and nitrogen conditions, 1.761 g (5 mmol) of TFMOB was dissolved in 6 mL of N, N-dimethylacetamide, and 1.1231 g (5.01 mmol) of 1,2,4,5-cyclohexanetetracarboxylic dianhydride was slowly added. Within half an hour of reaction, 6 mL of N, N-dimethylacetamide was added three times. The solid content of the obtained system was 21%. After stirring for 8 hours, the reaction solution was transferred into a vacuum oven for degassing at room temperature to obtain a uniform polyamic acid glue solution (PAA glue solution). After the PAA glue is cast on a glass plate to form a film, it is transferred to a muffle furnace for thermal imidization, maintained at 40°C for 100 minutes under vacuum conditions to remove the solvent, and then heated to 100°C at 1°C / min, maintained at 100°C for 1 hour, then heated to 200°C at 1°C / min, maintained at 220°C for 1 hour, then heated to 300°C at 1°C / min, maintained at 300°C for 1 hour, and thermal imidization is completed to obtain a polyimide film with a thickness of 20 μm. The glass transition temperature of the polyimide film is above 350°C, which meets the application requirements.

[0132] Comparative Example 2

[0133] In an ice-water bath and nitrogen conditions, 1.601 g (5 mmol) of TFMB was dissolved in 6 mL of N, N-dimethylacetamide, and 1.1231 g (5.01 mmol) of 1,2,4,5-cyclohexanetetracarboxylic dianhydride was slowly added. Within half an hour of reaction, 6 mL of N, N-dimethylacetamide was added three times. The solid content of the obtained system was 20 wt%. After stirring for 8 hours, the reaction solution was transferred into a vacuum oven for degassing at room temperature to obtain a uniform polyamic acid glue solution (PAA glue solution). After the PAA glue is cast on a glass plate to form a film, it is transferred to a muffle furnace for thermal imidization, maintained at 40°C for 100 minutes under vacuum conditions to remove the solvent, and then heated to 100°C at 1°C / min, maintained at 100°C for 1 hour, then heated to 200°C at 1°C / min, maintained at 200°C for 1 hour, then heated to 300°C at 1°C / min, maintained at 300°C for 1 hour, and thermal imidization is completed to obtain a polyimide film with a thickness of 15 μm. The glass transition temperature of the polyimide film is above 350°C, which meets the application requirements.

[0134] Comparative Example 3

[0135] In an ice-water bath and nitrogen conditions, 2.792g (5mmol) AB-TFMB was dissolved in 10mL N,N-dimethylacetamide, and 1.1231g (5.01mmol) 1,2,4,5-cyclohexanetetracarboxylic dianhydride was slowly added. Within half an hour, 6mL of N,N-dimethylacetamide was added three times. The solid content of the obtained system was 21%. After stirring for 8h, the reaction solution was transferred into a vacuum oven for degassing at room temperature to obtain a uniform polyamic acid glue solution (PAA glue solution). After the PAA glue is cast on a glass plate to form a film, it is transferred to a muffle furnace for thermal imidization, maintained at 40°C for 100 minutes under vacuum conditions to remove the solvent, and then heated to 100°C at 1°C / min, maintained at 100°C for 1 hour, then heated to 200°C at 1°C / min, maintained at 200°C for 1 hour, then heated to 300°C at 1°C / min, maintained at 300°C for 1 hour, and thermal imidization is completed to obtain a polyimide film with a thickness of 15 μm. The glass transition temperature of the polyimide film is above 350°C, which meets the application requirements.

[0136] [Test Example 1] Linear thermal expansion coefficient test

[0137] The polyimide films obtained in the examples and comparative examples were tested for linear thermal expansion coefficients according to the following method. The results are shown in Table 1.

[0138] Linear thermal expansion coefficient (CTE): The CTE was measured using a thermomechanical analyzer in a nitrogen atmosphere with a load of 50 mN applied and a heating rate of 10° C. / min to obtain an average value.

[0139] Table 1

[0140]

[0141] It can be seen from Table 1 that the polyimide film obtained in the embodiment of the present application has a lower thermal expansion coefficient.

[0142]

Test Example 2

[0143] The polyimide films obtained in the examples and comparative examples were subjected to transmittance tests as shown in the following method. The results are shown in Table 2.

[0144] Total light transmittance (TT): The total light transmittance was measured using a UV-visible spectrometer.

[0145] Light transmittance at a wavelength of 450 nm (T): The transmittance was measured at 450 nm using an ultraviolet spectrophotometer.

[0146] Table 2

[0147]

[0148] It can be seen from Table 2 that the total light transmittance TT of the polyimide obtained in the embodiment of the present application is above 85%, and the light transmittance T at 450nm is above 80%, which has good comprehensive light transmittance performance and can meet the application requirements.

[0149]

Test Example 3

[0150] The polyimide films obtained in the examples and comparative examples were subjected to water absorption test as shown in the following method. The results are shown in Table 3.

[0151] Water absorption rate (RMA): 3 pieces of 40×20 cm polyimide film are dried at 120°C for 2 hours, and then placed in a constant temperature and humidity chamber at 23°C / 50% RH for more than 24 hours. The weight change before and after is calculated according to the following formula: RMA (%) = [(weight after moisture absorption - weight after drying) / weight after drying] × 100%.

[0152] Table 3

[0153]

[0154] The present invention has been described in detail above in conjunction with specific implementations and exemplary examples, but these descriptions cannot be understood as limiting the present invention. Those skilled in the art understand that, without departing from the spirit and scope of the present invention, a variety of equivalent substitutions, modifications or improvements may be made to the technical solution of the present invention and its implementation methods, all of which fall within the scope of the present invention. The scope of protection of the present invention shall be subject to the attached claims.

Claims

1. A compound having a structure shown in formula (I): in, In formula (I), R 1 is selected from fluorine-substituted alkoxy-substituted biphenyl groups, R 2 Selected from aromatic hydrocarbon groups, R 4 Selected from carbonyl-containing groups, two R 2 Same or different, two R 4 Same or different.

2. The compound according to claim 1, It is characterized in that In formula (I), R 1 Selected from Where R 3 Selected from fluorine-substituted alkoxy, preferably, R 3 Selected from trifluoro-substituted C1-C10 alkoxy groups.

3. The compound according to claim 1, It is characterized in that In formula (I), R 2 is selected from phenyl and / or substituted phenyl, preferably, R 2 The present invention is one selected from the group consisting of phenyl, alkyl-substituted phenyl and halogen-substituted phenyl, preferably one selected from the group consisting of phenyl, C1-C10 alkyl-substituted phenyl, fluorine-substituted phenyl, chlorine-substituted phenyl and bromine-substituted phenyl.

4. The compound according to any one of claims 1 to 3, It is characterized in that In formula (I), R 4 Selected from Among them, the carbonyl group and R 2 connect.

5. A method for preparing the compound according to any one of claims 1 to 4, include: (1) NH 2 -R 1 -NH 2 with NO 2 -R 2 -C(=O)Cl to obtain an intermediate of formula (II); (2) the intermediate of formula (II) is reacted in the presence of a catalyst and a reducing agent to obtain a compound of formula (I); 6. The preparation method according to claim 5, It is characterized in that In step (1), NH 2 -R 1 -NH 2 with NO 2 -R 2 The molar ratio of -C(=O)Cl is 1:(1-10), preferably 1:(2-8); and / or, The reaction in step (1) is carried out at -10 to 35°C, preferably at 0 to 30°C; and / or, In step (1), the method is carried out in the presence of an alkaline substance; preferably, the alkaline substance is selected from at least one of triethylamine, pyridine, alkyl-substituted pyridine, N,N-diisopropylethylamine, triethylenediamine, quinoline, and isoquinoline; and / or, Step (1) is carried out in an organic solvent, and the organic solvent is selected from one or a mixture of two or more of ethyl acetate, dichloromethane, dimethyl sulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide and N-methylpyrrolidone in any proportion.

7. The preparation method according to claim 5 or 6, It is characterized in that In step (2), the catalyst is selected from a metal carbon catalyst, preferably at least one selected from a palladium carbon catalyst, a nickel carbon catalyst, and a platinum carbon catalyst; and / or, In step (2), the reducing agent is selected from at least one of hydrogen, hydrazine hydrate, formic acid, ammonium formate and sodium formate; preferably, the ratio of the total weight of the intermediate represented by formula (II) and the reducing agent to the weight of the solvent is 1:(2-20).

8. The preparation method according to claim 7, It is characterized in that In step (2), the amount of the catalyst used is 1wt% to 10wt% of the intermediate represented by formula (II); and / or, in step (2), the weight ratio of the reducing agent to the intermediate represented by formula (II) is (1 to 20):1; and / or, in step (2), the reaction is carried out at 20 to 100°C, preferably at 50 to 70°C.

9. Use of the compound according to any one of claims 1 to 4 or the compound obtained by the preparation method according to any one of claims 5 to 8 in polyimide.

10. A polyimide comprising a polymerization product of a diamine compound and a dianhydride compound, wherein the diamine compound comprises a diamine compound I and an optional diamine compound II, wherein the diamine compound I is selected from the compound according to any one of claims 1 to 4 or a compound obtained by the preparation method according to any one of claims 5 to 8; Preferably, the dianhydride compound is selected from at least one of tetracarboxylic dianhydride compounds, preferably at least one of the compounds represented by formula (III): In formula (III), A is selected from a cycloalkane group, a bicycloalkane group, an aromatic hydrocarbon group, an aromatic ether group, and an aromatic ketone group; More preferably, in formula (III), A is selected from any one of the following groups:

11. The polyimide according to claim 10, It is characterized in that The diamine compound II is selected from other diamine compounds except the diamine compound I; preferably, the diamine compound II is selected from ethylenediamine, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane, 1,12-diaminododecane, difluorobutylene diamine, 1,6-diphenyl-2,5-hexanediamine, 1,2-diaminocyclohexane, 1,3-diaminocyclohexane, 1,4-diaminocyclohexane, trans-1,4-diaminocyclohexane, 1,2-bis(2-aminoethyl)cyclohexane, 1,3-bis(2-aminoethyl)cyclohexane, 2-aminoethyl)cyclohexane, 1,4-bis(2-aminoethyl)cyclohexane, o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, 3,3'-p-phenylenediamine, 2-fluoro-5-methyl-1,4-phenylenediamine, 2,6-dimethoxy-1,4-phenylenediamine, 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 4,4'-aminodiphenylmethane, 2,2-bis(3-aminophenyl)propane, 2,2-bis(4-aminophenyl)propane, 2-(3-aminophenyl)-2-(4-aminophenyl)propane, 1,1-bis(3-aminophenyl)-1-phenylethane, 1,1-bis(4 1-(4-aminophenyl)-1-phenylethane, 1,3-bis(3-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,4-bis(3-aminophenoxy)benzene, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminobenzoyl)benzene, 1,3-bis(3-aminobenzoyl)benzene, 1,4-bis(4-aminobenzoyl)benzene, 1,4-bis(3-aminobenzoyl)benzene, 1,3-bis(3-amino-α,α-dimethylbenzyl)benzene, 1,3-bis(4-amino-α,α-dimethylbenzyl)benzene, 1,4-bis(3-amino-α,α-dimethylbenzyl)benzene, 1,4-bis(4-aminobenzoyl)benzene, 2,6-bis(3-aminophenoxy)benzylnitrile, 2,6-bis(3-aminophenoxy)pyridine, bis[4-(3-aminophenoxy)phenyl]ether, bis[4-(4-aminophenoxy)phenyl]ether, 2,2-bis[4-(3-aminophenoxy)phenyl]propane, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 1,3-bis[4-(3-aminophenoxy)benzoyl]benzene, 1,3-bis[4-(4-aminophenoxy)benzoyl]benzene, 1,4-bis[4-(3-aminophenoxy)benzoyl]benzene, 1,4-bis[4-(4-aminophenoxy)benzoyl]benzene, 1,3-Bis[4-(3-aminophenoxy)-α,α-dimethylbenzyl]benzene, 1,3-bis[4-(4-aminophenoxy)-α,α-dimethylbenzyl]benzene, 6,6'-bis(3-aminophenoxy)-3,3,3',3'-tetramethyl-1,1'-bisspiroindene, 6,6'-bis(4-aminophenoxy)-3,3,3',3'tetramethyl-1,1'-bisspiroindene, 6,6-bis(4-aminophenoxy)-3,3,3',3'-tetramethyl-1,1'-bisspiroindene, 5,2-dimethyl-4,5-pyrimidinediamine, 2-methoxy-4,5-pyrimidinediamine, 4,6-pyrimidinediamine, 2-vinyl-4,6-pyrimidinediamine, 2,5-pyrimidinediamine, 5-(4-fluorophenyl)-4 ,5-pyrimidinediamine, 6-(4-fluorophenyl)-2,4-pyrimidinediamine, 6-tert-butyl-2,4-pyrimidinediamine, 6-methyl-2,4-pyrimidinediamine, 2-methyl-4,6-pyrimidinediamine, 2-ethyl-4,6-pyrimidinediamine, bis(aminomethyl)ether, bis(2-aminoethyl)ether, bis(3-aminopropyl)ether, bis[(2-aminomethoxy)ethyl]ether, bis[2-(2-aminoethoxy)ethyl]ether, bis[2-(3-aminooxy)ethyl]ether, 1,2-bis(aminomethoxy)ethane, 1,2-bis(aminoethoxy)ethane, 1,2-bis[2-(aminomethoxy)ethoxy]ethane, 1,2-bis[2-(2-aminoethoxy)ethoxy]ethane, ethylene glycol bis(3-amino 1,4-diamino-2-fluorobenzene, 1,4-diamino-2,3-difluorobenzene, 1,4-diamino-2,5-difluorobenzene, 1,4-diamino-2,6-difluorobenzene, 1,4-diamino-2,3,5-trifluorobenzene, 1,4-diamino-2,3,5,6-tetrafluorobenzene, 1,4-diamino-2-(trifluoromethyl)benzene, 1,4-diamino-2,3-bis(trifluoromethyl)benzene, 1,4-diamino-2,5 -bis(trifluoromethyl)benzene, 1,4-diamino-2,6-bis(trifluoromethyl)benzene, 1,4-diamino-2,3,5-tri(trifluoromethyl)benzene, 1,4-diamino-2,3,5,6-tetra(trifluoromethyl)benzene, 2-fluorobenzidine, 3-fluorobenzidine, 2,3-difluorobenzidine, 2,5-difluorobenzidine, 2,6-difluorobenzidine, 2,2'-difluorobenzidine, 3,3'-difluorobenzidine, 2,3'-difluorobenzidine, 2,2',3-trifluorobenzidine, 2,3,3'-trifluorobenzidine, 2,2',5-trifluorobenzidine, 2,2',6-trifluorobenzidine, 2,3',5-trifluorobenzidine, 2,3',6-trifluorobenzidine, 2,2',3,3'-tetrafluorobenzidine, 2,2',5,5'-tetrafluorobenzidine, 2,2',6,6'-tetrafluorobenzidine, 2,2'3,3',6,6'-hexafluorobenzidine, 2,2',3,3',5,5',6,6'-octafluorobenzidine, 2-(trifluoromethyl)benzidine, 3-(trifluoromethyl)benzidine, 2,3-bis(trifluoromethyl)benzidine, 2,5-bis(trifluoromethyl)benzidine, 2,6-bis(trifluoromethyl)benzidine, 2,3'-bis(trifluoromethyl)benzidine, 2,2',3-tris(trifluoromethyl)benzidine, 2,3,3'-tris(trifluoromethyl)benzidine, 2,2',5-tris(trifluoromethyl)benzidine ) benzidine, 2,2',6-tris(trifluoromethyl)benzidine, 2,3',5-tris(trifluoromethyl)benzidine, 2,3',6-tris(trifluoromethyl)benzidine, 2,2',3,3'-tetrakis(trifluoromethyl)benzidine, 2,2',5,5'-tetrakis(trifluoromethyl)benzidine, 2,2',6,6'-tetrakis(trifluoromethyl)benzidine, (1S,2S)-1,2-bis(4-fluorophenyl)-1,2-ethylenediamine, (1S,2S)-1,2-di-1-naphthyl-1,2-ethylenediamine, 1,2-bis(4-bromophenyl)ethylenediamine, (R,R)-1,2-bis(4-cyanophenyl)-1,2-ethylenediamine; More preferably, based on 100 mol % of the total amount of the diamine compound I and the optional diamine compound II, the amount of the diamine compound I is greater than 20 mol %, preferably greater than 60 mol %. More preferably, the molar ratio of the diamine compound to the dianhydride compound is 1:(1 to 1.1), preferably 1:(1 to 1.05).

12. Use of the polyimide according to claim 10 or 11 in a film.

13. A polyimide film obtained by using the polyimide according to claim 12.

14. Use of the polyimide according to claim 10 or 11, or the polyimide film according to claim 13 in substrates, color filters, printed materials, luminescent materials, electronic devices, flexible display screens, liquid crystal display devices, electronic paper, and optical films.

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