Alkynyl-containing triamine monomer and application thereof in preparation of polyamide acid resin or polyimide film

Abstract

The invention provides an alkynyl-containing triamine monomer and application of the alkynyl-containing triamine monomer in preparation of polyamide acid resin or a polyimide film. A polymer molecular chain of the polyimide resin is connected with a high-temperature-resistant carborane structure, so that the polyimide resin has excellent thermal stability; meanwhile, the polyimide resin takes an alkynyl-containing triamine monomer with a novel structure as a raw material, so that the problem of compatibility between an inorganic filler for providing a carborane structure and polyamide acid is effectively solved, and the polyimide resin has excellent mechanical properties. The tensile strength of the prepared polyimide film is up to 361MPa, the elastic modulus is up to 13.3 GPa, the glass transition temperature is as low as 368 DEG C, the 5% thermal weight loss temperature is up to 613 DEG C, the thermal expansion coefficient at 50-450 DEG C is as low as 2.1 ppm / DEG C, and the polyimide film can be used in the fields of integrated circuits, flexible display, high-frequency communication, electronic packaging and the like with high requirements on the high-temperature environment stability of the film.

Description

Technical Field

[0001] The invention belongs to the technical field of polymer materials, and in particular 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 requirements for high-temperature resistance of materials are becoming higher and higher, and traditional epoxy resin-based composite materials can no longer meet the requirements. Polyimide, as a type of polymer material containing an imide ring structure on the main chain, is regarded as an ideal material that can be used stably and for a long time in high-temperature environments because of its excellent high-temperature resistance, corrosion resistance, flame resistance, and excellent mechanical and dielectric properties.

[0003] In the 1960s and 1970s, high-temperature resistant polyimide 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 has disadvantages such as poor thermal oxidation stability and high toxicity of MDA monomer. Therefore, researchers used PDA / ODA and 6FDA to replace MDA and BTDA respectively, and the use temperature of the obtained polyimide composite material was increased to above 371°C, but the high price of 6FDA also limited the application of this type of polyimide composite material. In addition, researchers also improved the high temperature resistance of the polymer by replacing the phenyl acetylene end capping agent. This method significantly improved the thermal oxidation stability and toughness of the material, but the long-term use temperature was low and it has not been widely used.

[0005] Since the thermal decomposition temperature of polyimide resin is difficult to exceed 500°C under the influence of organic chemical bond energy, and the long-term use temperature is generally below 425°C, in order to further improve its heat resistance, inorganic structural fillers have gradually entered the field of vision of researchers. Adding inorganic structures, such as cage-type silsesquioxane and carborane, to polyimide resin can greatly improve the high temperature resistance and thermal oxidation stability of polyimide resin.

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

[0007] For another example, the Chinese invention patent application with publication number CN111606936A discloses a method for preparing a triamine compound containing a tricarborane cage structure, a copolymer polyimide, and a polyimide composite material. The method designs and synthesizes a triamine containing tricarborane, and then introduces the triamine into the polyimide main chain through a condensation reaction with MDA and a-BPDA, and finally mixes it with a 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 the polyimide / inorganic filler composite system, due to the large steric hindrance of the inorganic filler and the compatibility problem between the inorganic filler and the polymer, the growth of the polymer molecular chain is affected, and only polyimide oligomers can be synthesized, resulting in the composite film becoming brittle or difficult to form a film, and the mechanical properties are reduced. Therefore, how to take advantage of the inorganic filler without destroying the polymer properties and prepare polyimide composite materials with high mechanical properties and high thermal stability has always been the focus of researchers. Summary of the invention

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

[0010] 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, which has a structure as shown below:

[0012]

[0013] Wherein, R1 or R2 is 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 an alkynyl-containing triamine monomer;

[0015] Preferably, in an inert atmosphere, aniline and concentrated hydrochloric acid are mixed, and then alkynyl-containing formaldehyde is slowly added dropwise, the molar ratio of alkynyl-containing formaldehyde to aniline is 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 filtering, washing and drying;

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

[0017] Alkynyl-containing triamine monomer Then, the present invention provides the use of the above-mentioned alkynyl-containing triamine monomer in the preparation of polyamic acid resin. The above-mentioned polyamic acid resin is prepared by the following method:

[0018] Under an inert atmosphere, the alkynyl-containing triamine monomer as claimed in 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'-biphenyl tetracarboxylic dianhydride (s-BPDA), 2,3',3,4'-biphenyl tetracarboxylic dianhydride (a-BPDA), bisphenol A type diether dianhydride (BPADA), p-phenylene-triphenylene dianhydride (TAHQ), 3,3',4,4'-diphenyl sulfone tetracarboxylic dianhydride (DSDA), 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 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, the carborane structure is first introduced into the polymer molecular chain of the polyamic acid resin 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.

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

[0029] The polymer molecular chain of the polyimide resin of the present invention is connected with a high temperature resistant carborane structure, so it has excellent thermal stability; at the same time, the polyimide resin of the present invention uses an alkynyl-containing triamine monomer as a raw material, and 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 crosslinking degree and alkynyl content of the polyimide resin can be controlled as needed by controlling the amount of the alkynyl-containing triamine monomer, which makes the polyimide resin have excellent mechanical properties. The tensile strength of the polyimide film prepared by the present invention is as high as 361MPa, the elastic modulus is as high as 13.3GPa, 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℃, 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 the mixture was dripped over about 20 min, and then heated to 180°C for reaction for 8 h; 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 the alkynyl triamine monomer A-1 of this embodiment.

[0034] The structural formulas of the alkynyl-containing formaldehyde A and the 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 min, and then heated to 180°C to react for 8 h; 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 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 min, and then heated to 180°C to react for 8 h; after the reaction, 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 C-1.

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

[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, in 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 NMP were added to a reaction bottle equipped with a mechanical stirrer, and fully stirred and dissolved at room temperature, and 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 NMP to make it completely dissolved in the reaction solution, and then the temperature was raised to 20° C. and stirred for reaction 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 is evenly and slowly poured on the surface of a glass substrate, and a film is formed with a 250 μm scraper. The film is then vacuum treated at 120° C. for 30 min to remove excess solvent, and then heated in stages under a nitrogen atmosphere. The heating program is as follows: 150° C. for 30 min, 250° C. for 30 min, 350° C. for 40 min, and 450° C. for 40 min. 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-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, in 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 NMP were added to a reaction bottle equipped with a mechanical stirrer, and the mixture was fully stirred and dissolved at room temperature, and 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 NMP to make it completely dissolved in the reaction solution, and then the temperature was raised to 20° C. and stirred for reaction for 8 hours to obtain a 15 wt% polyamic acid solution PAA-2;

[0055] (2) preparing polyimide film;

[0056] Specifically, the polyamic acid solution PAA-2 is evenly and slowly poured on the surface of the glass substrate, and a film is formed with a 250 μm scraper. The film is then vacuum treated at 120° C. for 30 min to remove excess solvent, and then heated in stages under a nitrogen atmosphere. The heating program is as follows: 150° C. for 30 min, 250° C. for 30 min, 350° C. for 40 min, and 450° C. for 40 min. 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-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, in 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 NMP were added to a reaction bottle equipped with a mechanical stirrer, and fully stirred and dissolved at room temperature, and 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 NMP to make it completely dissolved in the reaction solution, and then the temperature was raised to 20° C. and stirred for reaction 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 is evenly and slowly poured on the surface of the glass substrate, and a film is formed with a 250 μm scraper. The film is then vacuum treated at 120° C. for 30 min to remove excess solvent, and then heated in stages under a nitrogen atmosphere. The heating program is as follows: 150° C. for 30 min, 250° C. for 30 min, 350° C. for 40 min, and 450° C. for 40 min. 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-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, in 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 NMP were added to a reaction bottle equipped with a mechanical stirrer, and fully stirred and dissolved at room temperature, and then ODPA (130.2882 g, 0.42 mol) was slowly added, and the reactant powder hanging on the wall was washed with 123.6086 g NMP to make it completely dissolved in the reaction solution, and then the temperature was 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 is evenly and slowly poured on the surface of the glass substrate, and a film is formed with a 250 μm scraper. The film is then vacuum treated at 120° C. for 30 min to remove excess solvent, and then heated in stages under a nitrogen atmosphere. The heating program is as follows: 150° C. for 30 min, 250° C. for 30 min, 350° C. for 40 min, and 450° C. for 40 min. 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-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, in 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 NMP were added to a reaction bottle equipped with a mechanical stirrer, and the mixture was fully stirred and dissolved at room temperature, and then ODPA (130.2882 g, 0.42 mol) was slowly added, and the reactant powder hanging on the wall was washed with 123.9649 g NMP to make it completely dissolved in the reaction solution, and then the temperature was raised to 15° C. and stirred for reaction for 8 hours to obtain an 18 wt% polyamic acid solution PAA-5;

[0073] (2) preparing polyimide film;

[0074] Specifically, the polyamic acid solution PAA-45 is evenly and slowly poured on the surface of the glass substrate, and a film is formed with 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-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, in 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 NMP were added to a reaction bottle equipped with a mechanical stirrer, and the mixture was fully stirred and dissolved at room temperature, and then ODPA (130.2882 g, 0.42 mol) was slowly added, and the reactant powder hanging on the wall was washed with 123.9649 g NMP to make it completely dissolved in the reaction solution, and then the temperature was raised to 15° C. and stirred for reaction 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 is evenly and slowly poured on the surface of a glass substrate, and a film is formed with a 250 μm scraper. The film is then vacuum treated at 120° C. for 30 min to remove excess solvent, and then heated in stages under a nitrogen atmosphere. The heating program is as follows: 150° C. for 30 min, 250° C. for 30 min, 350° C. for 40 min, and 450° C. for 40 min. 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-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 NMP were added to a reaction bottle equipped with a mechanical stirrer, and the mixture was fully stirred and dissolved at room temperature, and then PMDA (45.8052 g, 0.21 mol) and s-BPDA (61.7862 g, 0.21 mol) were slowly added, and the reactant powder hanging on the wall was washed with 61.2306 g NMP to make it completely dissolved in the reaction solution, and then the temperature was raised to 25° C. and stirred for reaction for 12 h to obtain a 20 wt % polyamic acid solution PAA-7;

[0085] (2) preparing polyimide film;

[0086] Specifically, the polyamic acid solution PAA-7 is evenly and slowly poured on the surface of the glass substrate, and a film is formed with a 250 μm scraper. The film is then vacuum treated at 120° C. for 30 min to remove excess solvent, and then heated in stages under a nitrogen atmosphere. The heating program is as follows: 150° C. for 30 min, 250° C. for 30 min, 350° C. for 40 min, and 450° C. for 40 min. 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-7.

[0087] Embodiment 11

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

[0089] (1) preparing polyamic acid resin;

[0090] Specifically, in 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 NMP were added to a reaction bottle equipped with a mechanical stirrer, and the mixture was fully stirred and dissolved at room temperature, and then PMDA (45.8052 g, 0.21 mol) and s-BPDA (61.7862 g, 0.21 mol) were slowly added, and the reactant powder hanging on the wall was washed with 61.6476 g NMP to make it completely dissolved in the reaction solution, and then the temperature was raised to 25° C. and stirred for reaction for 12 h to obtain a 20 wt% polyamic acid solution PAA-8;

[0091] (2) preparing polyimide film;

[0092] Specifically, the polyamic acid solution PAA-8 is evenly and slowly poured on the surface of the glass substrate, and a film is formed with 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-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, in 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 NMP were added to a reaction bottle equipped with a mechanical stirrer, and the mixture was fully stirred and dissolved at room temperature, and then PMDA (45.8052 g, 0.21 mol) and s-BPDA (61.7862 g, 0.21 mol) were slowly added, and the reactant powder hanging on the wall was washed with 61.6476 g NMP to make it completely dissolved in the reaction solution, and then the temperature was raised to 25° C. and stirred for reaction 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 is evenly and slowly poured on the surface of the glass substrate, and a film is formed with a 250 μm scraper. The film is then vacuum treated at 120° C. for 30 min to remove excess solvent, and then heated in stages under a nitrogen atmosphere. The heating program is as follows: 150° C. for 30 min, 250° C. for 30 min, 350° C. for 40 min, and 450° C. for 40 min. 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-9.

[0099] Embodiment 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 bottle 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), heated and stirred at 110°C for 12 h, after the reaction was completed, the reaction solution was poured into methanol for precipitation, filtered, washed twice with methanol, washed three times with water, and dried at 60°C in vacuum to obtain a high temperature resistant polyimide resin precursor PAA-10;

[0105] (3) preparing polyimide film;

[0106] Specifically, the polyimide resin precursor PAA-10 is fully dissolved in NMP, and then evenly and slowly poured on the surface of a glass substrate, and a 250 μm scraper is used to form a film. 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-10.

[0107] Embodiment 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) preparing polyimide film;

[0114] Similar to Example 13, a high temperature resistant polyimide film PI-11 was obtained.

[0115] Embodiment 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) preparing polyimide film;

[0122] Similar to 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) preparing polyimide film;

[0130] Similar to Example 13, a high temperature resistant polyimide film PI-13 was obtained.

[0131] Embodiment 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) preparing polyimide film;

[0138] Similar to Example 13, a high temperature resistant polyimide film PI-14 was obtained.

[0139] Embodiment 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) preparing polyimide film;

[0146] Similar to Example 13, a high temperature resistant polyimide film PI-15 was obtained.

[0147] Embodiment 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) preparing polyimide film;

[0154] Similar to Example 13, a high temperature resistant polyimide film PI-16 was obtained.

[0155] Embodiment 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) preparing polyimide film;

[0162] Similar to Example 13, a high temperature resistant polyimide film PI-17 was obtained.

[0163] Embodiment 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) preparing polyimide film;

[0170] Similar to 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 NMP were added to a reaction bottle equipped with a mechanical stirrer, and the mixture was fully stirred and dissolved at room temperature, and then s-BPDA (123.5724 g, 0.42 mol) was slowly added, and the reactant powder hanging on the wall was washed with 120.8566 NMP to make it completely dissolved in the reaction solution, and then the temperature was raised to 20° C. and stirred for reaction for 8 h to obtain a 15 wt% polyamic acid solution PAA-19;

[0175] (2) preparing a polyimide film;

[0176] Specifically, the polyamic acid solution PAA-19 is evenly and slowly poured on the surface of the glass substrate, and a film is formed with 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-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, in a nitrogen atmosphere, BAFL (139.3760 g, 0.4 mol) and 1105.6232 g NMP were added to a reaction bottle equipped with a mechanical stirrer, and the mixture was fully stirred and dissolved at room temperature, and then ODPA (130.2882 g, 0.42 mol) was slowly added, and the reactant powder hanging on the wall was washed with 122.8470 g NMP to make it completely dissolved in the reaction solution, and then the temperature was raised to 15° C. and stirred for reaction 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 on the surface of the glass substrate, and a film is formed with 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, p-PDA (43.2560 g, 0.4 mol) and 543.0506 g NMP were added to a reaction bottle equipped with a mechanical stirrer under a nitrogen atmosphere, and the mixture was fully 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, and the reactant powder hanging on the wall was washed with 60.3389 g NMP to make it completely dissolved in the reaction solution. The mixture was then heated to 20° C. and stirred for reaction for 8 h to obtain a 20 wt% polyamic acid solution PAA-21.

[0187] (2) preparing a polyimide film;

[0188] Specifically, the polyamic acid solution PAA-21 is evenly and slowly poured on the surface of the glass substrate, and a film is formed with 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-21.

[0189] Various properties of the polyimide films prepared in the above-mentioned 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; indicating 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 (PI-1 to PI-9) is not introduced, 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 cross-linking degree of 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 is independently selected from -CH2-, -CH2-CH2-, 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, characterized in that: Aniline and concentrated hydrochloric acid are mixed, and then alkynyl-containing formaldehyde is slowly added dropwise, the molar ratio of alkynyl-containing formaldehyde to aniline is 1:(2-6), and the mixture is reacted at 100-180° C. for 6-12 hours; after the reaction is completed, the alkynyl-containing triamine monomer is obtained after filtering, 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-containing triamine monomer as claimed in 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, characterized in that The aromatic diamines include 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, characterized in that The aromatic dianhydride includes one or more of pyromellitic dianhydride, hexafluoroisopropyl phthalic anhydride, 3,3',4,4'-diphenyl ether tetracarboxylic dianhydride, 3,3',4,4'-benzophenone tetracarboxylic dianhydride, 3,3',4,4'-biphenyl tetracarboxylic dianhydride, 2,3',3,4'-biphenyl tetracarboxylic dianhydride, bisphenol A type diether dianhydride, p-phenylene-diphenyl trimellitic 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 (NMP), N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc), tetrahydrofuran (THF), and dimethyl sulfoxide (DMSO).

8. The polyamic acid resin according to claim 5, characterized in that 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 8-16h.

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 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; Alternatively, the carborane structure is first introduced into the polymer molecular chain of the polyamic acid resin 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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