An acetylenic group-containing triamine monomer and its use in the preparation of a polyamic acid resin or polyimide film

Abstract

The application provides an acetylenic group-containing triamine monomer and application thereof in preparation of a polyamide acid resin or a polyimide film. The polyimide resin has a high-temperature-resistant carborane structure connected to a polymer molecular chain, and thus has excellent thermal stability. Meanwhile, the polyimide resin is prepared from a novel acetylenic group-containing triamine monomer, and thus effectively solves the compatibility problem between an inorganic filler used for providing the carborane structure and the polyamide acid, which makes the polyimide resin have excellent mechanical properties. The polyimide film prepared by the application has a tensile strength of 361 MPa, an elastic modulus of 13.3 GPa, a glass transition temperature as low as 368 DEG C, a 5% thermal weight loss temperature as high as 613 DEG C, and a thermal expansion coefficient as low as 2.1 ppm / DEG C at 50-450 DEG C, and can be used in fields with high requirements for film high-temperature environmental stability, such as integrated circuits, flexible display, high-frequency communication, electronic packaging and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of polymer materials, and particularly relates to an alkynyl-containing triamine monomer and application thereof in preparing polyamic acid resin or polyimide film. Background Art

[0002] With the continuous development of high-frequency communications, electronic packaging and other fields, the demand for high-temperature resistance of materials is becoming increasingly stringent, and traditional epoxy resin-based composite materials can no longer meet these requirements. Polyimide, a type of polymer material containing an imide ring structure in its backbone, is considered an ideal material for long-term stable use in high-temperature environments due to its excellent high-temperature resistance, corrosion resistance, flame retardancy, and excellent mechanical and dielectric properties.

[0003] In the 1960s and 1970s, high-temperature resistant polyimides began to be extensively studied. PMR-15, as a representative product of this period, was prepared in methanol using MDA and BTDA as monomers and NA as a capping agent. It has excellent mechanical properties and can be used continuously for thousands of hours at 288°C. It has been widely used in many fields such as aircraft engine fairings, fan systems, and missile air intake covers.

[0004] However, PMR-15 suffers from shortcomings such as poor thermal and oxidative stability and the high toxicity of the MDA monomer. Therefore, researchers have replaced MDA and BTDA with PDA / ODA and 6FDA, respectively, raising the operating temperature of the resulting polyimide composite to over 371°C. However, the high price of 6FDA also limits the application of this type of polyimide composite. In addition, researchers have also improved the polymer's high-temperature resistance by replacing the phenylacetylene end-capping agent. This method significantly improves the material's thermal and oxidative stability and toughness, but the long-term operating temperature is relatively low and has not been widely used.

[0005] Because the thermal decomposition temperature of polyimide resins rarely exceeds 500°C due to the influence of organic chemical bonds, and their long-term operating temperature is generally below 425°C, researchers are increasingly interested in inorganic structural fillers to further improve their heat resistance. Incorporating inorganic structures, such as cage-type silsesquioxanes and carboranes, into polyimide resins can significantly improve their high-temperature resistance and thermal-oxidative stability.

[0006] For example, Chinese invention patent application publication number CN101816924A discloses a method for preparing a polyimide containing a carborane structure. The method introduces carborane into the polyimide backbone by polycondensing diaminophenyl-o-carborane or diaminophenyl-m-carborane with aromatic dianhydride. This method significantly improves the thermal stability of the polyimide resin, and the 5% thermal weight loss temperature in air atmosphere is increased from 475°C to 541°C.

[0007] For example, Chinese invention patent application publication number CN111606936A discloses a method for preparing a triamine compound containing a tricarborane cage structure, a copolymerized polyimide, and a polyimide composite material. The method designs and synthesizes a triamine containing tricarborane, then reacts it with MDA and α-BPDA to introduce the triamine into the polyimide main chain, and finally mixes it with carbon fiber woven cloth to prepare a polyimide composite material. The peak temperature of the oligomer polyimide reaches 388°C, and the glass transition temperature of the polyimide composite material is greater than 500°C.

[0008] In polyimide / inorganic filler composite systems, the inorganic filler's large steric hindrance and compatibility issues with the polymer hinder the growth of the polymer chain, resulting in the synthesis of only polyimide oligomers. This leads to brittle or difficult film formation of the composite film and reduced mechanical properties. Therefore, how to utilize the advantages of inorganic fillers without compromising the properties of the polymer to prepare polyimide composite materials with high mechanical properties and high thermal stability has been a research focus for researchers. Summary of the Invention

[0009] The purpose of the present invention is to provide an alkynyl-containing triamine monomer and its application in the preparation of polyamic acid resin or polyimide film. The polyimide film prepared using the alkynyl-containing triamine monomer has excellent thermal stability and mechanical properties.

[0010] In order to achieve the above-mentioned object of the invention, the technical solution of the present invention is as follows:

[0011] First, the present invention provides an alkynyl-containing triamine monomer having the following structure:

[0012]

[0013] Wherein, R1 or R2 are independently selected from -CH2-, -CH2-CH2-,

[0014] Secondly, the present invention provides a method for preparing the above-mentioned alkynyl-containing triamine monomer, which comprises: reacting aniline, concentrated hydrochloric acid and alkynyl-containing formaldehyde under an inert atmosphere to obtain the alkynyl-containing triamine monomer;

[0015] Preferably, under an inert atmosphere, aniline and concentrated hydrochloric acid are mixed, and then alkynyl-containing formaldehyde is slowly added dropwise, with the molar ratio of alkynyl-containing formaldehyde to aniline being 1:(2-6), and the reaction is carried out at 100-180° C. for 6-12 hours; after the reaction is completed, the alkynyl-containing triamine monomer is obtained by filtering, washing, and drying;

[0016] The alkynyl-containing formaldehyde has the structure shown below:

[0017] Alkynyl-containing triamine monomers The present invention provides the use of the above-mentioned alkynyl-containing triamine monomers in the preparation of polyamic acid resins. The above-mentioned polyamic acid resins are prepared by the following method:

[0018] Under an inert atmosphere, the alkynyl group-containing triamine monomer according to claim 1 is copolymerized with aromatic diamine and aromatic dianhydride in an organic solvent to obtain a polyamic acid resin.

[0019] Preferably, the aromatic diamine monomers include 4,4'-diaminodiphenyl ether (4,4'-ODA), 3,4'-diaminodiphenyl ether (3,4'-ODA), 4,4'-diamino-2,2'-dimethylbiphenyl (m-TD), 4,4'-diaminobenzanilide (DABA), 4,4'-diaminodiphenyl sulfone (4,4'-DDS), 3,3'-diaminodiphenyl sulfone (3,3'-DDS), p-phenylenediamine (p-PDA), m-phenylenediamine One or more of diamine (m-PDA), 3,3',5,5'-tetramethylbenzidine (TMB), 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl (TFMB), 9,9-dimethylfluorene-2,7-diamine (SA-1), 2-(4-aminophenyl)-5-aminobenzimidazole (APBIA), 2-(4-aminophenyl)-5-aminobenzoxazole (APBOA), and 9,9-bis(4-aminophenyl)fluorene (BAFL).

[0020] The aromatic dianhydride includes one or more of pyromellitic dianhydride (PMDA), hexafluoroisopropylphthalic anhydride (6FDA), 3,3',4,4'-diphenyl ether tetracarboxylic dianhydride (ODPA), 3,3',4,4'-benzophenone tetracarboxylic dianhydride (BTDA), 3,3',4,4'-biphenyltetracarboxylic dianhydride (s-BPDA), 2,3',3,4'-biphenyltetracarboxylic dianhydride (a-BPDA), bisphenol A diether dianhydride (BPADA), p-phenylene-diphenyltrimethylol dianhydride (TAHQ), 3,3',4,4'-diphenyl sulfone tetracarboxylic dianhydride (DSDA), and 9,9-bis(3,4-dicarboxyphenyl)fluorene dianhydride (BPAF);

[0021] The organic solvent is one or more of N-methylpyrrolidone (NMP), N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc), tetrahydrofuran (THF), and dimethyl sulfoxide (DMSO).

[0022] Preferably, the molar ratio of the aromatic diamine to the aromatic dianhydride is 1:(0.95-1.05), and the molar ratio of the alkynyl-containing triamine monomer to the aromatic dianhydride is (0-0.05):1;

[0023] The reaction temperature of the copolymerization reaction is 0-50°C, and the reaction time is 8-16h.

[0024] Then, the present invention also provides the use of the above-mentioned alkynyl-containing triamine monomer or the above-mentioned polyamic acid resin in the preparation of a polyimide film.

[0025] The polyimide film is prepared by the following method:

[0026] The polyamic acid resin is dissolved in an organic solvent, coated to form a film, and then subjected to thermal imidization or chemical imidization reaction to obtain the polyimide film;

[0027] Alternatively, a carborane structure is first introduced into the polymer molecular chain of the polyamic acid resin by macromolecular reaction to obtain a polyimide resin precursor; the polyimide resin precursor is then dissolved in an organic solvent, coated into a film, and then subjected to thermal imidization or chemical imidization reaction to obtain the polyimide film.

[0028] Compared with the prior art, the technical effects of the present invention are embodied in:

[0029] The polyimide resin of the present invention has a high-temperature resistant carborane structure connected to its polymer molecular chain, thus having excellent thermal stability. At the same time, the polyimide resin of the present invention uses an alkynyl-containing triamine monomer as a raw material. The alkynyl-containing triamine monomer can effectively solve the compatibility problem between the inorganic filler used to provide the carborane structure and the polyamic acid. Moreover, by controlling the amount of the alkynyl-containing triamine monomer, the crosslinking degree and alkynyl content of the polyimide resin can be controlled as needed, which makes the polyimide resin have excellent mechanical properties. The polyimide film prepared by the present invention has a tensile strength of up to 361 MPa, an elastic modulus of up to 13.3 GPa, a glass transition temperature (Tg) as low as 368°C, and a 5% thermal weight loss temperature (Td). 5％ ) is as high as 613℃, and the coefficient of thermal expansion (CTE) is as low as 2.1ppm / ℃ at 50-450℃. It can be used in integrated circuits, flexible displays, high-frequency communications, electronic packaging and other fields that require high stability of thin films in high-temperature environments. DETAILED DESCRIPTION

[0030] The following examples are given to further illustrate the technical solution of the present invention.

[0031] Example 1

[0032] This embodiment provides an alkynyl-containing triamine monomer, and its preparation method is as follows:

[0033] Under a nitrogen atmosphere, freshly distilled aniline (38.8508 g, 0.4 mol) and 80 ml of concentrated hydrochloric acid were added to a three-necked flask, heated to 60°C and stirred for 1 h to fully mix the two; then, alkynyl formaldehyde A (26.536 g, 0.1 mol) was added using a constant pressure dropping funnel and dripped over about 20 min, and then the temperature was raised to 180°C and reacted for 8 h; after the reaction was completed, it was cooled to room temperature, dissolved in hydrochloric acid and filtered, and the filtrate was dropwise added with sodium hydroxide solution to adjust the pH to 7, and filtered under reduced pressure again. The solid was washed with deionized water, methanol, and deionized water, respectively, and vacuum dried to obtain the alkynyl triamine monomer A-1 of this embodiment.

[0034] The structural formulas of alkynyl-containing formaldehyde A and alkynyl-containing triamine monomer A-1 are:

[0035]

[0036] Example 2

[0037] This embodiment provides an alkynyl-containing triamine monomer, and its preparation method is as follows:

[0038] Under a nitrogen atmosphere, freshly distilled aniline (55.8762 g, 0.6 mol) and 100 ml of concentrated hydrochloric acid were added to a three-necked flask, heated to 60°C and stirred for 1 h to fully mix the two; then, alkynyl formaldehyde B (22.125 g, 0.1 mol) was added using a constant pressure dropping funnel, and the mixture was dripped over about 20 minutes, and then the temperature was raised to 180°C and reacted for 8 hours; after the reaction was completed, the mixture was cooled to room temperature, and hydrochloric acid was added to dissolve and filter, and sodium hydroxide solution was added dropwise to the filtrate to adjust the pH to 7, and the mixture was filtered under reduced pressure again. The solid was washed with deionized water, methanol, and deionized water, respectively, and vacuum dried to obtain alkynyl triamine monomer B-1.

[0039] The structural formulas of the alkynyl-containing formaldehyde B and the alkynyl-containing triamine monomer B-1 are:

[0040]

[0041] Example 3

[0042] Under a nitrogen atmosphere, freshly distilled aniline (55.8762 g, 0.6 mol) and 100 ml of concentrated hydrochloric acid were added to a three-necked flask, heated to 60°C and stirred for 1 h to fully mix the two; then, alkynyl formaldehyde C (22.125 g, 0.1 mol) was added using a constant pressure dropping funnel, and the mixture was dripped over about 20 minutes, and then heated to 180°C and reacted for 8 hours; after the reaction, the mixture was cooled to room temperature, dissolved in hydrochloric acid and filtered, and the filtrate was dropwise added with sodium hydroxide solution to adjust the pH to 7, and filtered under reduced pressure again. The solid was washed with deionized water, methanol, and deionized water, respectively, and vacuum dried to obtain alkynyl triamine monomer C-1.

[0043] The structural formulas of the alkynyl-containing formaldehyde C and the alkynyl-containing triamine monomer C-1 are:

[0044]

[0045] Example 4

[0046] This embodiment provides a polyimide film, which is prepared by the following method:

[0047] (1) preparing polyamic acid resin;

[0048] Specifically, under a nitrogen atmosphere, alkynyl triamine monomer A-1 (2.2290 g, 0.0084 mol), APBIA (89.7040 g, 0.4 mol) and 1099.0777 g of NMP were added to a reaction flask equipped with a mechanical stirrer, and the mixture was thoroughly stirred and dissolved at room temperature. Then, s-BPDA (123.5724 g, 0.42 mol) was slowly added, and the reactant powder hanging on the wall was washed with 122.1197 g of NMP to completely dissolve it in the reaction solution. The temperature was then raised to 20° C. and stirred for 8 hours to obtain a 15 wt% polyamic acid solution PAA-1.

[0049] (2) preparing polyimide film;

[0050] Specifically, the polyamic acid solution PAA-1 was evenly and slowly poured onto the surface of a glass substrate, and a film was formed using a 250 μm scraper. The film was then vacuum-treated at 120°C for 30 minutes to remove excess solvent, and then heated in stages under a nitrogen atmosphere. The heating program was as follows: 150°C for 30 minutes, 250°C for 30 minutes, 350°C for 40 minutes, and 450°C for 40 minutes. After cooling to room temperature, the glass substrate was placed in deionized water and peeled off to obtain a high-temperature resistant polyimide film PI-1.

[0051] Example 5

[0052] This embodiment provides a polyimide film, which is prepared by the following method:

[0053] (1) preparing polyamic acid resin;

[0054] Specifically, under a nitrogen atmosphere, alkynyl triamine monomer B-1 (3.2718 g, 0.0084 mol), APBIA (89.7040 g, 0.4 mol) and 1109.3959 g of NMP were added to a reaction flask equipped with a mechanical stirrer, and the mixture was thoroughly stirred and dissolved at room temperature. Then, s-BPDA (123.5724 g, 0.42 mol) was slowly added, and the reactant powder hanging on the wall was washed with 122.7106 g of NMP to completely dissolve it in the reaction solution. The temperature was then raised to 20° C. and stirred for 8 hours to obtain a 15 wt% polyamic acid solution PAA-2.

[0055] (2) preparing polyimide film;

[0056] Specifically, the above-mentioned polyamic acid solution PAA-2 was evenly and slowly poured onto the surface of a glass substrate, and a film was formed using a 250μm scraper. The film was then vacuum-treated at 120°C for 30 minutes to remove excess solvent, and then heated in stages under a nitrogen atmosphere. The heating program was as follows: 150°C for 30 minutes, 250°C for 30 minutes, 350°C for 40 minutes, and 450°C for 40 minutes. After cooling to room temperature, the glass substrate was placed in deionized water and peeled off to obtain a high-temperature resistant polyimide film PI-2.

[0057] Example 6

[0058] This embodiment provides a polyimide film, which is prepared by the following method:

[0059] (1) preparing polyamic acid resin;

[0060] Specifically, under a nitrogen atmosphere, alkynyl triamine monomer C-1 (3.2718 g, 0.0084 mol), APBIA (89.7040 g, 0.4 mol) and 1109.3959 g of NMP were added to a reaction flask equipped with a mechanical stirrer, and the mixture was thoroughly stirred and dissolved at room temperature. Then, s-BPDA (123.5724 g, 0.42 mol) was slowly added, and the reactant powder adhering to the wall was rinsed with 122.7106 g of NMP to completely dissolve it in the reaction solution. The temperature was then raised to 20° C. and stirred for 8 hours to obtain a 15 wt% polyamic acid solution PAA-3.

[0061] (2) preparing polyimide film;

[0062] Specifically, the polyamic acid solution PAA-3 was evenly and slowly poured onto the surface of a glass substrate, and a film was formed using a 250 μm scraper. The film was then vacuum-treated at 120°C for 30 minutes to remove excess solvent, and then heated in stages under a nitrogen atmosphere. The heating program was as follows: 150°C for 30 minutes, 250°C for 30 minutes, 350°C for 40 minutes, and 450°C for 40 minutes. After cooling to room temperature, the glass substrate was placed in deionized water and peeled off to obtain a high-temperature resistant polyimide film PI-3.

[0063] Example 7

[0064] This embodiment provides a polyimide film, which is prepared by the following method:

[0065] (1) preparing polyamic acid resin;

[0066] Specifically, under a nitrogen atmosphere, alkynyl triamine monomer A-1 (1.6718 g, 0.0063 mol), BAFL (139.3760 g, 0.4 mol) and 1112.4775 g of NMP were added to a reaction flask equipped with a mechanical stirrer, and the mixture was thoroughly stirred and dissolved at room temperature. Then, ODPA (130.2882 g, 0.42 mol) was slowly added, and the reactant powder adhering to the wall was rinsed with 123.6086 g of NMP to completely dissolve it in the reaction solution. The temperature was then raised to 15° C. and stirred for 8 hours to obtain an 18 wt% polyamic acid solution PAA-4.

[0067] (2) preparing polyimide film;

[0068] Specifically, the polyamic acid solution PAA-4 was evenly and slowly poured onto the surface of a glass substrate, and a film was formed using a 250 μm scraper. The film was then vacuum-treated at 120°C for 30 minutes to remove excess solvent, and then heated in stages under a nitrogen atmosphere. The heating program was as follows: 150°C for 30 minutes, 250°C for 30 minutes, 350°C for 40 minutes, and 450°C for 40 minutes. After cooling to room temperature, the glass substrate was placed in deionized water and peeled off to obtain a high-temperature resistant polyimide film PI-4.

[0069] Example 8

[0070] This embodiment provides a polyimide film, which is prepared by the following method:

[0071] (1) preparing polyamic acid resin;

[0072] Specifically, under a nitrogen atmosphere, alkynyl triamine monomer B-1 (2.4539 g, 0.0063 mol), BAFL (139.3760 g, 0.4 mol) and 1115.6841 g of NMP were added to a reaction flask equipped with a mechanical stirrer, and the mixture was thoroughly stirred and dissolved at room temperature. ODPA (130.2882 g, 0.42 mol) was then slowly added, and the reactant powder adhering to the wall was rinsed with 123.9649 g of NMP to completely dissolve it in the reaction solution. The mixture was then heated to 15° C. and stirred for 8 hours to obtain an 18 wt% polyamic acid solution PAA-5.

[0073] (2) preparing polyimide film;

[0074] Specifically, the above-mentioned polyamic acid solution PAA-45 was evenly and slowly poured onto the surface of a glass substrate, and a film was formed using a 250μm scraper. The film was then vacuum-treated at 120°C for 30 minutes to remove excess solvent, and then heated in stages under a nitrogen atmosphere. The heating program was as follows: 150°C for 30 minutes, 250°C for 30 minutes, 350°C for 40 minutes, and 450°C for 40 minutes. After cooling to room temperature, the glass substrate was placed in deionized water and peeled off to obtain a high-temperature resistant polyimide film PI-5.

[0075] Example 9

[0076] This embodiment provides a polyimide film, which is prepared by the following method:

[0077] (1) preparing polyamic acid resin;

[0078] Specifically, under a nitrogen atmosphere, alkynyl triamine monomer C-1 (2.4539 g, 0.0063 mol), BAFL (139.3760 g, 0.4 mol) and 1115.6841 g of NMP were added to a reaction flask equipped with a mechanical stirrer, and the mixture was thoroughly stirred and dissolved at room temperature. ODPA (130.2882 g, 0.42 mol) was then slowly added, and the reactant powder adhering to the wall was rinsed with 123.9649 g of NMP to completely dissolve it in the reaction solution. The mixture was then heated to 15° C. and stirred for 8 hours to obtain an 18 wt% polyamic acid solution PAA-6.

[0079] (2) preparing polyimide film;

[0080] Specifically, the polyamic acid solution PAA-6 was evenly and slowly poured onto the surface of a glass substrate, and a film was formed using a 250 μm scraper. The film was then vacuum-treated at 120°C for 30 minutes to remove excess solvent, and then heated in stages under a nitrogen atmosphere. The heating program was as follows: 150°C for 30 minutes, 250°C for 30 minutes, 350°C for 40 minutes, and 450°C for 40 minutes. After cooling to room temperature, the glass substrate was placed in deionized water and peeled off to obtain a high-temperature resistant polyimide film PI-6.

[0081] Example 10

[0082] This embodiment provides a polyimide film, which is prepared by the following method:

[0083] (1) preparing polyamic acid resin;

[0084] Specifically, under a nitrogen atmosphere, triamine monomer A-1 (2.2290 g, 0.0084 mol), p-PDA (43.2560 g, 0.4 mol) and 551.0751 g of NMP were added to a reaction bottle equipped with a mechanical stirrer, and the mixture was thoroughly stirred and dissolved at room temperature. Then, PMDA (45.8052 g, 0.21 mol) and s-BPDA (61.7862 g, 0.21 mol) were slowly added. The reactant powder hanging on the wall was washed with 61.2306 g of NMP to completely dissolve it in the reaction solution. The temperature was then raised to 25° C. and stirred for 12 hours to obtain a 20 wt% polyamic acid solution PAA-7.

[0085] (2) preparing polyimide film;

[0086] Specifically, the polyamic acid solution PAA-7 was evenly and slowly poured onto the surface of a glass substrate, and a film was formed using a 250 μm scraper. The film was then vacuum-treated at 120°C for 30 minutes to remove excess solvent, and then heated in stages under a nitrogen atmosphere. The heating program was as follows: 150°C for 30 minutes, 250°C for 30 minutes, 350°C for 40 minutes, and 450°C for 40 minutes. After cooling to room temperature, the glass substrate was placed in deionized water and peeled off to obtain a high-temperature resistant polyimide film PI-7.

[0087] Example 11

[0088] This embodiment provides a polyimide film, which is prepared by the following method:

[0089] (1) preparing polyamic acid resin;

[0090] Specifically, under a nitrogen atmosphere, alkynyl triamine monomer B-1 (3.2718 g, 0.0084 mol), p-PDA (43.2560 g, 0.4 mol) and 554.8291 g of NMP were added to a reaction bottle equipped with a mechanical stirrer, and the mixture was thoroughly stirred and dissolved at room temperature. Then, PMDA (45.8052 g, 0.21 mol) and s-BPDA (61.7862 g, 0.21 mol) were slowly added. The reactant powder hanging on the wall was washed with 61.6476 g of NMP to completely dissolve it in the reaction solution. The temperature was then raised to 25° C. and stirred for 12 hours to obtain a 20 wt% polyamic acid solution PAA-8.

[0091] (2) preparing polyimide film;

[0092] Specifically, the polyamic acid solution PAA-8 was evenly and slowly poured onto the surface of a glass substrate, and a film was formed using a 250 μm scraper. The film was then vacuum-treated at 120°C for 30 minutes to remove excess solvent, and then heated in stages under a nitrogen atmosphere. The heating program was as follows: 150°C for 30 minutes, 250°C for 30 minutes, 350°C for 40 minutes, and 450°C for 40 minutes. After cooling to room temperature, the glass substrate was placed in deionized water and peeled off to obtain a high-temperature resistant polyimide film PI-8.

[0093] Example 12

[0094] This embodiment provides a polyimide film, which is prepared by the following method:

[0095] (1) preparing polyamic acid resin;

[0096] Specifically, under a nitrogen atmosphere, alkynyl triamine monomer C-1 (3.2718 g, 0.0084 mol), p-PDA (43.2560 g, 0.4 mol) and 554.8291 g of NMP were added to a reaction bottle equipped with a mechanical stirrer, and the mixture was thoroughly stirred and dissolved at room temperature. Then, PMDA (45.8052 g, 0.21 mol) and s-BPDA (61.7862 g, 0.21 mol) were slowly added. The reactant powder adhering to the wall was rinsed with 61.6476 g of NMP to completely dissolve it in the reaction solution. The mixture was then heated to 25° C. and stirred for 12 h to obtain a 20 wt% polyamic acid solution PAA-9.

[0097] (2) preparing polyimide film;

[0098] Specifically, the polyamic acid solution PAA-9 was evenly and slowly poured onto the surface of a glass substrate, and a film was formed using a 250 μm scraper. The film was then vacuum-treated at 120°C for 30 minutes to remove excess solvent, and then heated in stages under a nitrogen atmosphere. The heating program was as follows: 150°C for 30 minutes, 250°C for 30 minutes, 350°C for 40 minutes, and 450°C for 40 minutes. After cooling to room temperature, the glass substrate was placed in deionized water and peeled off to obtain a high-temperature resistant polyimide film PI-9.

[0099] Example 13

[0100] This embodiment provides a polyimide film, which is prepared by the following method:

[0101] (1) preparing polyamic acid resin;

[0102] Same as Example 4;

[0103] (2) preparing a polyimide resin precursor;

[0104] Specifically, the polyamic acid solution PAA-1 was poured into a reaction flask equipped with a mechanical stirrer, 1500 ml of toluene was added to completely dissolve it, and then 0.7848 g of silver nitrate was added. After it was completely dissolved, decaborane acetonitrile complex B was added. 10 H 12 (CH3CN)2 (1.8692 g, 0.00924 mol) was heated and stirred at 110°C for 12 h. After the reaction, the reaction solution was poured into methanol for precipitation. After filtration, it was washed with methanol twice, washed with water three times, and dried in vacuum at 60°C to obtain a high-temperature resistant polyimide resin precursor PAA-10.

[0105] (3) Preparation of polyimide film;

[0106] Specifically, the polyimide resin precursor PAA-10 was fully dissolved in NMP and then evenly and slowly poured onto the surface of a glass substrate. A film was formed using a 250 μm doctor blade. The film was then vacuum-treated at 120°C for 30 minutes to remove excess solvent. The temperature was then raised in stages under a nitrogen atmosphere. The heating program was as follows: 150°C for 30 minutes, 250°C for 30 minutes, 350°C for 40 minutes, and 450°C for 40 minutes. After cooling to room temperature, the glass substrate was placed in deionized water and peeled off to obtain a high-temperature resistant polyimide film PI-10.

[0107] Example 14

[0108] This embodiment provides a polyimide film, which is prepared by the following method:

[0109] (1) preparing polyamic acid resin;

[0110] Same as Example 5;

[0111] (2) preparing a polyimide resin precursor;

[0112] Same as Example 13;

[0113] (3) Preparation of polyimide film;

[0114] The same as Example 13, a high temperature resistant polyimide film PI-11 was obtained.

[0115] Example 15

[0116] This embodiment provides a polyimide film, which is prepared by the following method:

[0117] (1) preparing polyamic acid resin;

[0118] Same as Example 6;

[0119] (2) preparing a polyimide resin precursor;

[0120] Same as Example 13;

[0121] (3) Preparation of polyimide film;

[0122] The same as Example 13, a high temperature resistant polyimide film PI-12 was obtained.

[0123] Example 16

[0124] This embodiment provides a polyimide film, which is prepared by the following method:

[0125] (1) preparing polyamic acid resin;

[0126] Same as Example 7;

[0127] (2) preparing a polyimide resin precursor;

[0128] Same as Example 13;

[0129] (3) Preparation of polyimide film;

[0130] The same as Example 13, a high temperature resistant polyimide film PI-13 was obtained.

[0131] Example 17

[0132] This embodiment provides a polyimide film, which is prepared by the following method:

[0133] (1) preparing polyamic acid resin;

[0134] Same as Example 8;

[0135] (2) preparing a polyimide resin precursor;

[0136] Same as Example 13;

[0137] (3) Preparation of polyimide film;

[0138] The same as Example 13, a high temperature resistant polyimide film PI-14 was obtained.

[0139] Example 18

[0140] This embodiment provides a polyimide film, which is prepared by the following method:

[0141] (1) preparing polyamic acid resin;

[0142] Same as Example 9;

[0143] (2) preparing a polyimide resin precursor;

[0144] Same as Example 13;

[0145] (3) Preparation of polyimide film;

[0146] The same as Example 13, a high temperature resistant polyimide film PI-15 was obtained.

[0147] Example 19

[0148] This embodiment provides a polyimide film, which is prepared by the following method:

[0149] (1) preparing polyamic acid resin;

[0150] Same as Example 10;

[0151] (2) preparing a polyimide resin precursor;

[0152] 800 mL of toluene was used, and the rest was the same as in Example 13;

[0153] (3) Preparation of polyimide film;

[0154] The same as Example 13, a high temperature resistant polyimide film PI-16 was obtained.

[0155] Example 20

[0156] This embodiment provides a polyimide film, which is prepared by the following method:

[0157] (1) preparing polyamic acid resin;

[0158] Same as Example 11;

[0159] (2) preparing a polyimide resin precursor;

[0160] Same as Example 19;

[0161] (3) Preparation of polyimide film;

[0162] The same as Example 13, a high temperature resistant polyimide film PI-17 was obtained.

[0163] Example 21

[0164] This embodiment provides a polyimide film, which is prepared by the following method:

[0165] (1) preparing polyamic acid resin;

[0166] Same as Example 12;

[0167] (2) preparing a polyimide resin precursor;

[0168] Same as Example 19;

[0169] (3) Preparation of polyimide film;

[0170] The same as Example 13, a high temperature resistant polyimide film PI-18 was obtained.

[0171] Comparative Example 1

[0172] This comparative example is a polyimide film, which is prepared by the following method:

[0173] (1) preparing polyamic acid resin;

[0174] Specifically, under a nitrogen atmosphere, APBIA (89.7040 g, 0.4 mol) and 1087.7096 g of NMP were added to a reaction flask equipped with a mechanical stirrer, and the mixture was thoroughly stirred and dissolved at room temperature. Then, s-BPDA (123.5724 g, 0.42 mol) was slowly added, and the reactant powder adhering to the wall was rinsed with 120.8566 g of NMP to completely dissolve it in the reaction solution. The temperature was then raised to 20° C. and stirred for 8 h to obtain a 15 wt% polyamic acid solution PAA-19.

[0175] (2) Preparation of polyimide film;

[0176] Specifically, the above-mentioned polyamic acid solution PAA-19 was evenly and slowly poured onto the surface of a glass substrate, and a film was formed using a 250μm scraper. The film was then vacuum-treated at 120°C for 30 minutes to remove excess solvent, and then heated in stages under a nitrogen atmosphere. The heating program was as follows: 150°C for 30 minutes, 250°C for 30 minutes, 350°C for 40 minutes, and 450°C for 40 minutes. After cooling to room temperature, the glass substrate was placed in deionized water and peeled off to obtain a high-temperature resistant polyimide film PI-19.

[0177] Comparative Example 2

[0178] This comparative example is a polyimide film, which is prepared by the following method:

[0179] (1) preparing polyamic acid resin;

[0180] Specifically, under a nitrogen atmosphere, BAFL (139.3760 g, 0.4 mol) and 1105.6232 g of NMP were added to a reaction bottle equipped with a mechanical stirrer, and the mixture was thoroughly stirred and dissolved at room temperature. ODPA (130.2882 g, 0.42 mol) was then slowly added, and the reactant powder adhering to the wall was rinsed with 122.8470 g of NMP to completely dissolve it in the reaction solution. The temperature was then raised to 15° C. and stirred for 8 hours to obtain an 18 wt% polyamic acid solution PAA-20.

[0181] (2) having a polyimide film;

[0182] Specifically, the polyamic acid solution PAA-20 is evenly and slowly poured onto the surface of a glass substrate, and a film is formed using a 250 μm scraper. The film is then vacuum-treated at 120°C for 30 minutes to remove excess solvent, and then heated in stages under a nitrogen atmosphere. The heating program is as follows: 150°C for 30 minutes, 250°C for 30 minutes, 350°C for 40 minutes, and 450°C for 40 minutes. After cooling to room temperature, the glass substrate is placed in deionized water and peeled off to obtain a high-temperature resistant polyimide film PI-20.

[0183] Comparative Example 3

[0184] This comparative example is a polyimide film, which is prepared by the following method:

[0185] (1) preparing polyamic acid resin;

[0186] Specifically, under a nitrogen atmosphere, p-PDA (43.2560 g, 0.4 mol) and 543.0506 g of NMP were added to a reaction bottle equipped with a mechanical stirrer, and the mixture was thoroughly stirred and dissolved at room temperature. Then, PMDA (45.8052 g, 0.21 mol) and s-BPDA (61.7862 g, 0.21 mol) were slowly added. The reactant powder hanging on the wall was washed with 60.3389 g of NMP to completely dissolve it in the reaction solution. The temperature was then raised to 20° C. and stirred for 8 hours to obtain a 20 wt% polyamic acid solution PAA-21.

[0187] (2) Preparation of polyimide film;

[0188] Specifically, the above-mentioned polyamic acid solution PAA-21 was evenly and slowly poured onto the surface of a glass substrate, and a film was formed using a 250μm scraper. The film was then vacuum-treated at 120°C for 30 minutes to remove excess solvent, and then heated in stages under a nitrogen atmosphere. The heating program was as follows: 150°C for 30 minutes, 250°C for 30 minutes, 350°C for 40 minutes, and 450°C for 40 minutes. After cooling to room temperature, the glass substrate was placed in deionized water and peeled off to obtain a high-temperature resistant polyimide film PI-21.

[0189] Various properties of the polyimide films prepared in Examples 4-21 and Comparative Examples 1-3 were tested, and the test results are shown in Table 1.

[0190] Table 1

[0191]

[0192] As shown in Table 1, the tensile strength of the polyimide film prepared by the present invention is as high as 361 MPa, the elastic modulus is as high as 13.3 GPa, the glass transition temperature (Tg) is as low as 368 ° C, and the 5% thermal weight loss temperature (Td 5％ ) is as high as 613°C, and the coefficient of thermal expansion (CTE) is as low as 2.1ppm / °C at 50-450°C; this indicates that the polyimide film prepared by the present invention has excellent thermal stability and mechanical properties (including excellent tensile strength and toughness). Moreover, it can be seen that in the present invention, the introduction of the carborane structure not only does not lead to a weakening of the toughness of the film, but under the premise of the presence of the alkynyl-containing triamine monomer, the various properties of PI-10 to PI-18 are better than those when the carborane structure is not introduced (PI-1 to PI-9), indicating that the alkynyl-containing triamine monomer can effectively solve the compatibility problem between the inorganic filler used to provide the carborane structure and the polyamic acid, and the introduction of the carborane structure will not affect the toughness of the film.

[0193] In addition, compared with PI-4, PI-5 and PI-6, PI-1, PI-2 and PI-3 have better performance, indicating that by controlling the amount of alkynyl-containing triamine monomer, the degree of cross-linking of the polyimide resin can be controlled as needed, thereby controlling the performance of the film: increasing the amount of alkynyl-containing monomer in the film can further optimize the performance of the film.

Claims

1. An alkynyl-containing triamine monomer, characterized in that Has the following structure: ； Wherein, R1 or R2 are independently selected from 、 、 、 、 ; The specific compounds are: 、 or .

2. The method for preparing an alkynyl-containing triamine monomer according to claim 1, wherein include: Under an inert atmosphere, aniline, concentrated hydrochloric acid and alkynyl-containing formaldehyde react to obtain an alkynyl-containing triamine monomer; The alkynyl-containing formaldehyde has the structure shown below:

3. The preparation method according to claim 2, wherein Aniline and concentrated hydrochloric acid are mixed, and then alkynyl-containing formaldehyde is slowly added dropwise, with the molar ratio of alkynyl-containing formaldehyde to aniline being 1:(2-6), and the reaction is carried out at 100-180°C for 6-12 hours. After the reaction is completed, the alkynyl-containing triamine monomer is obtained after filtration, washing, and drying.

4. Use of the alkynyl-containing triamine monomer according to claim 1 in the preparation of polyamic acid resin.

5. A polyamic acid resin, characterized in that Made by the following method: Under an inert atmosphere, the alkynyl group-containing triamine monomer according to claim 1 is copolymerized with aromatic diamine and aromatic dianhydride in an organic solvent to obtain a polyamic acid resin.

6. The polyamic acid resin according to claim 5, wherein The aromatic diamine is selected from one or more of 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diamino-2,2'-dimethylbiphenyl, 4,4'-diaminobenzanilide, 4,4'-diaminodiphenyl sulfone, 3,3'-diaminodiphenyl sulfone, p-phenylenediamine, m-phenylenediamine, 3,3',5,5'-tetramethylbenzidine, 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl, 9,9-dimethylfluorene-2,7-diamine, 2-(4-aminophenyl)-5-aminobenzimidazole, 2-(4-aminophenyl)-5-aminobenzoxazole and 9,9-bis(4-aminophenyl)fluorene.

7. The polyamic acid resin according to claim 5, wherein The aromatic dianhydride is selected from one or more of pyromellitic dianhydride, hexafluoroisopropylphthalic anhydride, 3,3',4,4'-diphenyl ether tetracarboxylic dianhydride, 3,3',4,4'-benzophenone tetracarboxylic dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, 2,3',3,4'-biphenyltetracarboxylic dianhydride, bisphenol A type diether dianhydride, p-phenylene-diphenyltrimethylol dianhydride, 3,3',4,4'-diphenyl sulfone tetracarboxylic dianhydride and 9,9-bis(3,4-dicarboxyphenyl)fluorene dianhydride; The organic solvent is one or more of N-methylpyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, tetrahydrofuran and dimethyl sulfoxide.

8. The polyamic acid resin according to claim 5, wherein The molar ratio of the aromatic diamine to the aromatic dianhydride is 1:(0.95-1.05), and the molar ratio of the alkynyl-containing triamine monomer to the aromatic dianhydride is (0-0.05):1; The reaction temperature of the copolymerization reaction is 0-50°C, and the reaction time is 8-16 h.

9. Use of the alkynyl-containing triamine monomer according to claim 1 or the polyamic acid resin according to claim 5 in the preparation of a polyimide film.

10. A polyimide film, characterized in that: It is prepared by the following method: The polyimide film is prepared by dissolving the polyamic acid resin according to any one of claims 5 to 8 in an organic solvent, coating the resin to form a film, and then subjecting the film to thermal imidization or chemical imidization reaction; Alternatively, a carborane structure is first introduced into the polymer molecular chain of the polyamic acid resin according to any one of claims 5 to 8 by macromolecular reaction to obtain a polyimide resin precursor; then the polyimide resin precursor is dissolved in an organic solvent, coated into a film, and then subjected to thermal imidization or chemical imidization reaction to obtain the polyimide film.

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