阅读说明：本技术 一种含异靛蓝结构的二胺单体及其合成的黑色聚酰亚胺 (Diamine monomer containing isoindigo structure and black polyimide synthesized from diamine monomer ) 是由 叶强 许江婷 曹寮峰 王以淋 于 2020-05-27 设计创作，主要内容包括：本发明属于有机高分子材料技术领域,公开了一种含异靛蓝结构的二胺单体及其合成的黑色聚酰亚胺。本发明以卤代吲哚酮、卤代靛红、卤代烷(或酰化剂)、氨基苯硼酸频那醇酯(或硝基苯硼酸频那醇酯)为原料,合成了深红色或黑色的含异靛蓝结构的二胺单体。将合成的二胺单体(可加入其他二胺)与芳香族二酐进行缩聚反应得到聚酰胺酸溶液,通过热或化学酰亚胺化制备黑色聚酰亚胺。本发明以含大平面共轭强吸电子异靛蓝结构的二胺单体制备本征型黑色聚酰亚胺,该方法操作简单、反应高效,不需添加或涂覆任何遮光物质就能制备黑色聚酰亚胺。本发明制备的黑色聚酰亚胺遮光性能优良,在电子工业、宇航、仪表通讯等领域拥有广泛的应用价值。(The invention belongs to the technical field of organic polymer materials, and discloses a diamine monomer containing an isoindigo structure and black polyimide synthesized by the diamine monomer. The invention takes halogenated indolone, halogenated isatin, alkyl halide (or acylating agent) and amino-phenyl-boronic acid pinacol ester (or nitrophenyl-boronic acid pinacol ester) as raw materials to synthesize a deep red or black diamine monomer containing an isoindigo structure. And (3) carrying out polycondensation reaction on the synthesized diamine monomer (other diamine can be added) and aromatic dianhydride to obtain polyamic acid solution, and preparing the black polyimide through thermal or chemical imidization. The method for preparing the intrinsic black polyimide by using the diamine monomer containing the large-plane conjugated strong electron-withdrawing isoindigo structure has the advantages of simple operation and high reaction efficiency, and can prepare the black polyimide without adding or coating any shading substance. The black polyimide prepared by the invention has excellent shading performance and has wide application value in the fields of electronic industry, space navigation, instrument communication and the like.)

1. The diamine monomer containing the isoindigo structure and the black polyimide synthesized by the diamine monomer are characterized in that the chemical structure of the diamine monomer containing the isoindigo structure is shown as a formula (1):

2. the isoindigo structure-containing diamine monomer and the black polyimide synthesized by the same according to claim 1, wherein the synthesis of the isoindigo structure-containing diamine monomer comprises the following steps:

(1) taking halogenated indolone and halogenated isatin as raw materials, acetic acid as a solvent and concentrated hydrochloric acid as a catalyst, stirring and refluxing for about 24 hours, cooling to room temperature, performing suction filtration to obtain a solid, and washing with water, ethanol and ethyl acetate respectively and drying to obtain a product 1;

(2) performing N-alkylation or acylation on the product 1 obtained in the step (1), providing an alkaline environment by using DMF as a solvent and potassium carbonate, adding halogenated alkane or an acylating agent under a nitrogen atmosphere, pouring the solution into methanol after the reaction is finished, separating out, performing suction filtration to obtain a solid, and finally purifying by silica gel chromatography to obtain a product 2;

(3) reacting the product 2 in the step (2) with amino-containing phenylboronic acid pinacol ester by taking tetrakis (triphenylphosphine palladium) as a catalyst to obtain a diamine monomer containing an isoindigo structure;

(4) or reacting the product 2 in the step (2) with nitro-containing pinacol phenylboronate to obtain a dinitro compound containing an isoindigo structure, and further reducing to obtain a diamine monomer containing the isoindigo structure.

3. The diamine monomer containing isoindigo structure and the black polyimide synthesized from the same as claimed in claim 2, wherein the halogenated indolone of step (1) is selected from the group consisting of 4-iodo-2-indolone, 4-fluoro-2-indolone, 4-chloro-2-indolone, 4-bromo-2-indolone, 5-iodo-2-indolone, 5-fluoro-2-indolone, 5-chloro-2-indolone, 5-bromo-2-indolone, 6-iodo-2-indolone, 6-fluoro-2-indolone, 6-chloro-2-indolone, 6-bromo-2-indolone, 7-iodo-2-indolone, and mixtures thereof, 7-fluoro-2-indolone, 7-chloro-2-indolone, 7-bromo-2-indolone, 7-chloro-5-fluoroindolone, 6-chloro-5-fluoroindolone and other halogenated indolone.

4. The diamine monomer containing isoindigo structure and the black polyimide synthesized from the same as claimed in claim 2, wherein the halogenated isatin in the step (1) is 4-iodoisatin, 4-fluoroisatin, 4-chloroisatin, 4-bromoisatin, 5-iodoisatin, 5-fluoroisatin, 5-chloroisatin, 5-bromoisatin, 6-iodoisatin, 6-fluoroisatin, 6-chloroisatin, 6-bromoisatin, 7-iodoisatin, 7-fluoroisatin, 7-chloroisatin, 7-bromoisatin, 4-methoxy-7-chloroisatin, 5-chloro-7-methylisoindon, 4-bromo-7-methoxyisatin, 6-chloro-5-methylisoindon, 4-chloro-7-methylisoindon, 5-iodoisatin, or, One or more of 5-bromo-6-fluoro-isatin, 4-chloro-5-fluoro-isatin, 6-chloro-7-methyl-isatin, 6-bromo-5-methyl-isatin, 4-bromo-5-methyl-isatin and other halogenated isatins.

5. The diamine monomer containing isoindigo structures and the black polyimide synthesized by the same as claimed in claim 2, wherein the alkyl halide in step (2) is one or more of 1-bromo-2-octyldodecane, 1-fluoro-2-octyldodecane, 1-chloro-2-octyldodecane, 1-iodo-2-octyldodecane, 1-bromo-2-ethylhexane, 1-fluoro-2-ethylhexane, 1-chloro-2-ethylhexane, 1-iodo-2-ethylhexane, etc.; the acylating reagent is one or more of carboxylic acid methyl ester, carboxylic acid ethyl ester, carboxylic acid phenyl ester, acetic anhydride, propionic anhydride, succinic anhydride, maleic anhydride, benzoic anhydride, phthalic anhydride, formic acid, acetic acid, propionic acid, butyric acid, isovaleric acid, benzoic acid, malonic acid, succinic acid, acetyl chloride, benzoyl chloride, oxalyl chloride, chloroacetyl chloride, trichloroacetyl chloride and the like.

6. The diamine monomer containing isoindigo structure and the black polyimide synthesized from the same as claimed in claim 2, wherein the pinacol ester of phenyl boronic acid containing amino group in the step (3) is pinacol ester of 4-aminophenylboronic acid, pinacol ester of 3-cyano-4-aminophenylboronic acid, pinacol ester of 4-amino-3-chlorobenzeneboronic acid, pinacol ester of 4-amino-2-fluorobenzeneboronic acid, pinacol ester of 4-amino-3-fluorobenzeneboronic acid, pinacol ester of 4-amino-2-bromobenzeneboronic acid, pinacol ester of 4-amino-3-bromobenzeneboronic acid, pinacol ester of 4-amino-2-iodophenylboronic acid, pinacol ester of 4-amino-3-iodophenylboronic acid, pinacol ester of, One or more of 2-aminophenylboronic acid pinacol ester, 3-aminophenylboronic acid pinacol ester and the like; the nitryl-containing pinacol ester in the step (4) is one or more of 4-nitrophenylboronic acid pinacol ester, 4-nitro-3-chlorophenylboronic acid pinacol ester, 4-nitro-2-fluorophenylboronic acid pinacol ester, 4-nitro-3-fluorophenylboronic acid pinacol ester, 4-nitro-2-bromophenylboronic acid pinacol ester, 4-nitro-3-bromophenylboronic acid pinacol ester, 4-nitro-2-iodophenylboronic acid pinacol ester, 4-nitro-3-iodophenylboronic acid pinacol ester, 2-nitrophenylboronic acid pinacol ester, 3-nitrophenylboronic acid pinacol ester and the like.

7. The diamine monomer containing an isoindigo structure and the black polyimide synthesized by the diamine monomer according to claim 1, wherein the structure of the polyimide is represented by formula (2):

8. the diamine monomer containing an isoindigo structure and the black polyimide synthesized by the diamine monomer containing an isoindigo structure according to claim 6, wherein the synthesis method of the polyimide comprises the following steps:

(1) dissolving the prepared dry diamine monomer containing the isoindigo structure (other diamine can be added) in an anhydrous polar aprotic solvent, wherein the molar content of the diamine monomer containing the isoindigo structure is 10-100%. Then adding the dried dianhydride monomer in batches, and mechanically stirring for a period of time at low temperature to obtain a uniform polyamic acid solution;

(2) and (2) carrying out thermal imidization or chemical imidization on the polyamic acid solution obtained in the step (1) to obtain black polyimide containing an isoindigo structure.

9. The diamine monomer containing isoindigo structure and the black polyimide synthesized by the same as claimed in claim 8, wherein: in the step (1), other diamine monomers are one or more of diamines such as 4,4' -diamino diphenyl ether, m-phenylenediamine, p-xylylenediamine, biphenyldiamine, 4' -diamino diphenyl sulfide, benzidine, 3' -diamino biphenyl, 1, 3-bis (4-nitryl phenoxy) benzene, 1, 4-bis (4-nitryl phenoxy) benzene and the like; the dianhydride is one or more of pyromellitic dianhydride, 2,3, 3', 4-biphenyl dianhydride, 2,3, 2', 3' -biphenyl dianhydride, 3,3', 4,4' -biphenyl tetracarboxylic dianhydride, 3,3', 4,4' -benzophenone tetracarboxylic dianhydride, 2,3, 3', 4-benzophenone tetracarboxylic dianhydride, 2', 3,3' -diphenyl ether tetracarboxylic dianhydride, 3,4, 3', 4' -diphenyl ether dianhydride, 2,3, 2', 3' -diphenyl ether dianhydride, 2,3, 3', 4' -diphenyl ether tetracarboxylic dianhydride, 4,4' -oxydiphthalic dianhydride, etc.

10. The diamine monomer containing isoindigo structure and the black polyimide synthesized by the same as claimed in claim 8, wherein: the polar aprotic solvent in the step (1) is any one or more of N, N-dimethylformamide, N-dimethylacetamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, dimethyl sulfoxide and other solvents.

Technical Field

The invention belongs to the technical field of organic polymer materials, and particularly relates to a diamine monomer containing an isoindigo structure and black polyimide synthesized by the diamine monomer.

Background

Polyimide (PI) has excellent comprehensive properties, particularly high and low temperature resistance, dimensional stability, mechanical properties, radiation resistance, and the like, because it contains a stable aromatic heterocyclic structure in its molecule, and is widely used in the fields of electronics, electric appliances, aerospace, and the like. With the rapid development of economy, the living standard of people is continuously improved, and the requirements of people on the comprehensive performance of materials are higher and higher. The traditional PI film is mostly golden yellow due to a charge transfer complex generated between diamine and dianhydride, the conjugated plane of an aromatic ring structure is small, and the transparency is high. Therefore, the pattern of the underlying layer of the PI film or coating film is easily recognized, which easily causes leakage of related technologies, and has limited applications in the electronic industry, particularly in integrated circuits and the like.

The black polyimide film has the characteristics of opacity, low light absorption, low light transmittance, low light reflection coefficient and the like in addition to the unique excellent performance of the PI film, so that the black polyimide film can be widely applied to the fields of optics, electronics and the like with high requirements on light shielding performance. In recent years, the development and application research of black PI has attracted more and more attention from research teams at home and abroad, and the black PI is an excellent functional material in the future.

At present, there are two main methods for manufacturing black PI films. One is a PI film prepared by adding various micron or nanometer light-shielding substances such as carbon black, graphite, metal oxide, nigrosine, black inorganic or organic dyes such as black flower black, etc. during or after the synthesis process, and performing polycondensation reaction. For example, patent CN 108341950a discloses a method for preparing a black polyimide film by adding amino-containing organosiloxane to modify polyamic acid and adding carbon black, but this method requires high production conditions and complex preparation process, and mainly uses carbon black as a light-shielding substance, which reduces the mechanical properties, heat resistance, etc. of the material. Another method is to coat a layer of light-shielding material on the PI film, for example, patent CN102529262A discloses a high temperature resistant coating type black polyimide film and a preparation method thereof, in which acrylic black matte ink is coated on the upper and lower layers of the polyimide film, but the black coating is easy to fade and uneven, and in addition, the coating process is strict and the cost is higher.

The invention provides a preparation method of intrinsic polyimide, and the PI film or the coating prepared by the method has the advantages that the absorption band covers the whole visible light area, the covering effect is excellent, and the PI film or the coating has wide application prospects in the fields of electronic industry, aerospace and the like.

Disclosure of Invention

The first purpose of the invention is to synthesize a diamine monomer containing an isoindigo structure.

The second object of the present invention is to provide a method for synthesizing the diamine monomer.

It is a third object of the present invention to provide a black polyimide prepared from the above diamine monomer alone without adding or coating any light-shielding substance.

The fourth object of the present invention is to provide a method for preparing the black polyimide.

In order to achieve the above purpose, the invention provides the following technical scheme:

synthesis method of diamine monomer containing isoindigo structure

The chemical structure of the diamine monomer containing the isoindigo structure is shown as the formula (1):

wherein: r₁H atom or an aliphatic or aromatic group;

R₂an aliphatic or aromatic group, R₂Can be in the 5, 6, 7, 8 position on the phenyl ring, two R₂May be the same or different.

Formula (1).

A synthetic method of a diamine monomer containing an isoindigo structure comprises the following steps:

(1) taking bromoindolone and bromoisatin as raw materials, acetic acid as a solvent and concentrated hydrochloric acid as a catalyst, stirring and refluxing for about 24 hours, cooling to room temperature, performing suction filtration to obtain a solid, and washing with water, ethanol and ethyl acetate respectively, and drying to obtain a product 1;

(2) performing N-alkylation or acylation on the product 1 obtained in the step (1), providing an alkaline environment by using DMF as a solvent and potassium carbonate, adding halogenated alkane or an acylating agent under a nitrogen atmosphere, pouring the solution into methanol after the reaction is finished, separating out, performing suction filtration to obtain a solid, and finally purifying by silica gel chromatography to obtain a product 2;

(3) reacting the product 2 in the step (2) with amino-containing phenylboronic acid pinacol ester by taking tetrakis (triphenylphosphine palladium) as a catalyst to obtain a diamine monomer containing an isoindigo structure;

(4) or reacting the product 2 in the step (2) with nitro-containing pinacol phenylboronate to obtain a dinitro compound containing an isoindigo structure, and further reducing to obtain a diamine monomer containing the isoindigo structure.

Preparation of black polyimide

The black polyimide prepared from the diamine monomer containing the isoindigo structure has a structural formula shown in formula (2):

wherein: r₁H atom or an aliphatic or aromatic group;

R₂an aliphatic or aromatic radical, R₂Can be in the 5, 6, 7, 8 position on the phenyl ring, two R₂The positions of (a) and (b) may be the same or different:

formula (2).

The method for preparing the black polyimide by using the diamine monomer containing the isoindigo structure comprises the following steps:

(1) dissolving a dried diamine monomer containing an isoindigo structure shown in a formula (1) (other diamine can be added) in an anhydrous strong polar aprotic solvent, wherein the molar content of the diamine monomer containing the isoindigo structure is 10-100%. Then adding dried dianhydride monomers in batches, and mechanically stirring for a period of time at low temperature to obtain a uniform polyamic acid solution;

(2) and (2) carrying out thermal imidization or chemical imidization on the polyamic acid solution obtained in the step (1) to obtain black polyimide.

Preferably, the other diamine monomer is one or more of diamines such as 4,4' -diaminodiphenyl ether, m-phenylenediamine, p-xylylenediamine, biphenyldiamine, 4' -diaminodiphenyl sulfide, benzidine, 3' -diaminobiphenyl, 1, 3-bis (4-aminophenoxy) benzene, 1, 4-bis (4-aminophenoxy) benzene, and the like.

Preferably, the aromatic dianhydride is any one or more of pyromellitic dianhydride, 2,3, 3', 4-biphenyl dianhydride, 2,3, 2', 3' -biphenyl dianhydride, 3,3', 4,4' -biphenyl tetracarboxylic dianhydride, 3,3', 4,4' -benzophenone tetracarboxylic dianhydride, 2,3, 3', 4-benzophenone tetracarboxylic dianhydride, 2', 3,3' -diphenyl ether tetracarboxylic dianhydride, 3,4, 3', 4' -diphenyl ether dianhydride, 2,3, 2', 3' -diphenyl ether dianhydride, 2,3, 3', 4' -diphenyl ether tetracarboxylic dianhydride, 4,4' -oxydiphthalic dianhydride, and the like.

Preferably, the strong polar aprotic solvent is any one or more of N, N-dimethylformamide, N-dimethylacetamide, N-methylpyrrolidone, N-ethylpyrrolidone and dimethyl sulfoxide.

Preferably, the polycondensation reaction is carried out under anhydrous and nitrogen protection conditions.

Preferably, the molar ratio of the diamine monomer containing the isoindigo structure to the aromatic dianhydride is 1: 1-1.05.

Preferably, the polycondensation reaction is carried out at low temperature (ice bath), and the time of the polycondensation reaction is 12-24 h.

Preferably, the thermal imidization method is carried out under the conditions of 75-305 ℃ and the heating time of 5-12 h.

Preferably, the thermal imidization conditions are temperature programmed: 75-85 ℃/1 h-2 h, 105-125 ℃/1 h-2 h, 145-155 ℃/1 h-2 h, 195-205 ℃/0.5 h-1 h, 245-255 ℃/0.5 h-1 h, 295-305 ℃/0.5 h-1 h.

The black polyimide synthesized by the diamine monomer containing the isoindigo structure is used as a functional material and is widely applied to the application fields of high-temperature black labels, LED circuits, heater insulation and the like in light-proof and low-reflectivity.

Compared with the synthesis method reported in the prior art, the synthesis method of the diamine monomer and the polyimide has the following advantages:

(1) in the synthesis method of the diamine monomer, the raw materials are easy to synthesize, the reaction is efficient, and the solubility of the diamine monomer is good.

(2) The diamine monomer containing the large-plane conjugated strong electron-withdrawing isoindigo structure is synthesized by using halogenated indolone, halogenated isatin, alkyl halide (or acylating agent) and amino-phenyl-boronic acid pinacol ester (or nitrophenyl-boronic acid pinacol ester) as raw materials, and the color of the diamine monomer is deep red or black.

(3) The diamine monomer containing isoindigo structure (other diamine can be added) synthesized by the invention reacts with dianhydride to prepare the intrinsic black polyimide.

(4) According to the preparation method of the black polyimide disclosed by the invention, the black polyimide can be prepared without adding or coating any light shielding substance. Compared with the traditional polyimide, the film not only shows excellent shading performance, but also has very excellent own specific performance, has potential application value in the fields of electronic industry, aerospace and the like, and especially has very important significance for developing the technology of electronic product core materials.

Drawings

Fig. 1 shows nuclear magnetic hydrogen spectra and carbon spectra of diamine monomers containing isoindigo structures synthesized in example 1.

FIG. 2 is an infrared absorption spectrum of a black polyimide prepared in example 1.

FIG. 3 is a UV spectrum of a black polyimide prepared in example 1.

FIG. 4 is a schematic representation of a black polyimide prepared in example 1.

Detailed Description

The present invention will be described in further detail with reference to the following examples and drawings, but the method of carrying out the present invention is not limited thereto, and any modification and change made within the spirit and scope of the present invention should be construed as being within the scope of the present invention.

The drugs mentioned in the following examples are commercially available.