Carborane hybrid RTM polyimide resin and preparation method thereof

Abstract

The invention belongs to the technical field of resin-based composite material manufacturing, and relates to carborane hybridized RTM polyimide resin and a preparation method thereof. The carborane hybridized RTM polyimide resin is composed of a component A and a component B, the component A is used for adjusting the viscosity and the open period of the resin, the component B is used for adjusting the strength and the heat resistance of the resin, the component A is added into a high-concentration solution of the component B as powder subjected to imidization, a solvent is removed through vacuum low pressure, and the resin is obtained. And carrying out a high-temperature solvent-free imidization reaction to complete a cyclization process so as to obtain the carborane hybrid RTM polyimide resin with low volatile component content. A composite structure is adopted, low viscosity and a long open period can be obtained while high resistance is guaranteed, meanwhile, the low-boiling-point solvent is adopted as the reaction solvent, the production efficiency can be remarkably improved, and the process cost can be reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of resin-based composite material manufacturing, and relates to a carborane hybrid RTM polyimide resin and a preparation method thereof. Background Art

[0002] With the rapid development of aerospace technology at home and abroad, the demand for the application of more and more high-temperature resistant complex parts structures is becoming more and more urgent. Such complex structures are often difficult to achieve integral molding using traditional autoclave processes. Liquid molded polyimide has been widely concerned and applied in the field of aero engines due to its excellent performance characteristics. As early as the 1990s, NASA developed typical RTM molded polyimide resin grades such as PETI-RTM, PETI-298, PETI-330, and PETI-375, and carried out a lot of application research work, and has begun to verify and apply them in engine structures.

[0003] However, with the development of aerospace equipment such as high-speed missiles and hypersonic aircraft, there is a clear demand for polyimide that can withstand RTM molding at temperatures above 400°C. The molecular main chain of typical PETI-375 and other PETI-type polyimide resins is a purely organic structure. Even through molecular structure optimization design, it is difficult to meet the requirements of long-term service at 400°C. Invention patents CN103881091A, CN104945627A, CN 110498923 A, CN 107459648A and other patents disclose polyimide resins containing carborane structures. The above patents mainly use high-boiling point solvents for synthesis, and the obtained polyimide resins often have a large viscosity and are used in autoclave molding processes, which cannot meet the requirements of RTM processes for low viscosity and long open period. Summary of the invention

[0004] 1. Technical issues to be resolved

[0005] The technical problem to be solved by the present invention is to increase the long-term temperature resistance of RTM polyimide resin to 400°C, while obtaining its lower viscosity and longer process period to meet the application requirements of large-sized complex high-temperature resistant structures.

[0006] (II) Technical solution

[0007] In order to solve the above technical problems, the present invention provides a carborane hybrid RTM polyimide resin, wherein the raw materials for preparing the carborane hybrid RTM polyimide resin include component A and component B;

[0008] The component A comprises a structure shown in formula I:

[0009]

[0010] The component B comprises the structure shown in formula II:

[0011]

[0012] In formula II, X1 represents any one of the following substituents:

[0013]

[0014] n is 0, 1 or 2.

[0015] The present invention also provides a method for preparing component A:

[0016] S1.1 dissolving 4-phenylethynylbenzene anhydride in an alcohol solvent to react to obtain an esterification solution;

[0017] S1.2 dissolving the carborane diamine monomer in an organic solvent, and heating under the protection of an inert gas to obtain a diamine solution;

[0018] S1.3 mixing the esterification solution with the diamine solution to carry out a polymerization reaction to obtain a resin solution;

[0019] S1.4 heating the resin solution, reacting it under vacuum, and then cooling it to obtain a block resin containing the compound of formula I;

[0020] S1.5 The block resin is crushed to obtain component A;

[0021] The component A is resin powder with a particle size of 50-200 meshes.

[0022] As a preferred embodiment of the present invention, in step S1.1, the reaction temperature of the reaction is 60°C-90°C, the reaction time is 1h-4h, and the concentration of the esterification solution obtained by the reaction is 20wt%-80wt%.

[0023] As a preferred embodiment of the present invention, in step S1.2, the heating temperature is 40° C.-80° C., and the concentration of the diamine solution obtained by heating is 20wt%-80wt%.

[0024] As a preferred embodiment of the present invention, in step S1.3, the polymerization reaction comprises: pouring the esterification solution into the diamine solution, heating to 60°C-80°C for polymerization reaction for 1h-5h under stirring; then heating to 80-120°C, controlling the vacuum degree to ≤-0.09MPa, reacting for 1h-12h to obtain the resin solution.

[0025] As a preferred embodiment of the present invention, in step S1.4, the heating temperature is 150°C-260°C, and the reaction time under vacuum is 1h-6h.

[0026] The present invention also provides a method for preparing component B:

[0027] S2.1 dissolving 4-phenylethynylphthalic anhydride and 2,3,3',4'-biphenyltetracarboxylic dianhydride monomers in an alcohol solvent, and reacting to obtain an esterification solution;

[0028] S2.2 dissolving a diamine monomer and a carborane diamine monomer in an organic solvent, and heating under an inert gas to obtain a mixed diamine solution;

[0029] S2.3 pouring the esterification solution into the mixed diamine solution to carry out polymerization reaction to obtain a resin solution containing the compound of the structure represented by formula II, namely component B.

[0030] As a preferred embodiment of the present invention, the mass percentage content of the compound of the structure represented by formula II in the component B is 60wt%-90wt%.

[0031] As a preferred embodiment of the present invention, in step S2.1, the reaction temperature of the reaction is 60°C-90°C, the reaction time is 1h-6h, and the concentration of the obtained esterification solution is 20wt%-80wt%.

[0032] As a preferred embodiment of the present invention, in step S2.2, the heating temperature is 40° C.-60° C., and the concentration of the mixed diamine solution obtained by heating is 20wt%-80wt%.

[0033] As a preferred embodiment of the present invention, in step S2.3, the polymerization reaction comprises: pouring the esterification solution into the mixed diamine solution, heating to 60°C-80°C for polymerization reaction for 1h-5h under stirring; then heating to 80-120°C, maintaining the vacuum degree ≤-0.09MPa, reacting for 1h-12h, and obtaining component B.

[0034] The diamine monomers used in the present invention are selected from one or two of m-PDA, 3,4-ODA, TFMBZ, 1,3,4-APB, 4,4-MDA, 4,4-DDS, p-ODA, BAPP and FDA.

[0035] The organic solvent used in the present invention is one or a mixture of alcohol solvents, tetrahydrofuran, dioxane, N,N-dimethylacetamide, N,N-dimethylformamide, and N-methylpyrrolidone.

[0036] The alcohol solvent used in the present invention is one of methanol, ethanol, propanol, isopropanol, butanol and n-butanol, or a mixture of several of the above in any proportion.

[0037] The present invention also provides a method for preparing a carborane hybrid RTM polyimide resin, comprising the steps of:

[0038] S1. Component B is heated to a first temperature, component A is added thereto, stirred, then ultrasonically treated, then heated to a second temperature, reacted in vacuum, and then cooled to obtain a block of carborane hybrid RTM polyimide resin;

[0039] S2. crushing the blocky carborane hybrid RTM polyimide resin to obtain a powdery carborane hybrid RTM polyimide resin.

[0040] As a preferred embodiment of the present invention, the first temperature is 90-120°C, and the second temperature is 150°C-260°C.

[0041] As a preferred embodiment of the present invention, in step S1, the reaction time of the vacuum reaction is 1 h-6 h.

[0042] As a preferred embodiment of the present invention, in step S2, the particle size of the powdered carborane hybrid RTM polyimide resin is ≥20 mesh.

[0043] As a preferred embodiment of the present invention, the content of component A accounts for 10% to 90% of the total of component A and component B.

[0044] The unremoved volatile solvent content of the carborane hybrid RTM polyimide resin is ≤1%.

[0045] The present invention also provides an application of a carborane hybrid RTM polyimide resin in RTM, VARTM, VARI and RFI molding.

[0046] (III) Beneficial effects

[0047] The above technical solution of the present invention has the following advantages:

[0048] 1. The carborane hybrid RTM polyimide resin of the present invention is composed of component A and component B, which are compounded in a certain ratio, wherein component A is used to adjust the viscosity and open period of the resin, and component B is used to adjust the strength and heat resistance of the resin. Component A is added to a high-concentration solution of component B in the form of imidized powder, and then the polymerization solvent is removed by vacuum low-pressure polymerization, and then a high-temperature solvent-free imidization reaction is performed to complete the cyclization process to obtain a carborane hybrid RTM polyimide resin with a low volatile content.

[0049] 2. The carborane hybrid RTM polyimide resin of the present invention adopts a composite structure, which can obtain a lower viscosity and a longer open period while ensuring high resistance performance, and adopts a low boiling point solvent as a reaction solvent, which can significantly improve production efficiency and reduce process costs. At the same time, it can avoid the use of a large amount of toxic high boiling point solvents in the polymerization process, and can avoid the use of a large amount of volatile solvents in the washing and powdering process, which can significantly reduce the pollution problems caused by these solvents to the environment. DETAILED DESCRIPTION

[0050] The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0051] Preparation Example 1

[0052] This preparation example provides a powdered resin of component A, and the preparation method thereof comprises the steps of:

[0053] S1. 3016.49 g of 4-phenylethynylbenzene anhydride was dissolved in 4530 g of ethanol solvent, and refluxed at 78° C. for 4 h to obtain an esterification solution with a concentration of 40 wt %.

[0054] S2. 1983.51 g of carborane diamine monomer was dissolved in 4630 g of ethanol solvent, heated to 50° C. under inert gas protection, and stirred for 0.5 h to obtain a diamine solution with a concentration of 30 wt %.

[0055] S3. Pour the above-obtained esterification solution into the diamine solution, raise the temperature to 78°C under stirring in the reaction vessel and carry out polymerization reaction for 5 hours; further raise the temperature to 90°C, and apply continuous vacuum to the reaction vessel at a vacuum degree of ≤-0.09MPa. The reaction time is 6 hours. The organic solvent volatilized or generated during the reaction is collected by a special solvent recovery device to obtain a resin solution.

[0056] S4. The reaction vessel was heated to 200° C., reacted for 5 h under vacuum, and naturally cooled to obtain a block of component A resin.

[0057] S5. The obtained block resin is mechanically crushed by a pulverizer, and the particle size of the crushed resin is controlled to be 150 mesh-200 mesh to obtain a powdered resin of component A, ie, component A.

[0058] The structural formula of component A is as follows:

[0059]

[0060] Table 1 Basic properties of component A resin

[0061] Serial number Test items performance 1 Glass transition temperature, °C ＞600 2 Thermal decomposition temperature (5%), ℃ 660 3 Minimum viscosity of resin, Pa.s 0.08

[0062] Preparation Example 2

[0063] This preparation example provides a powdered resin of component A, and the preparation method thereof comprises the steps of:

[0064] S1. 3016.49 g of 4-phenylethynylbenzene anhydride was dissolved in 4530 g of ethanol solvent, and refluxed at 78° C. for 3 h to obtain an esterification solution with a concentration of 40 wt %.

[0065] S2. 1983.51 g of carborane diamine monomer was dissolved in 4630 g of dioxane, heated to 60° C. under inert gas protection, and stirred for 1 h to obtain a diamine solution with a concentration of 30 wt %.

[0066] S3. Pour the above-obtained esterification solution into the diamine solution, raise the temperature to 75°C under the stirring action of the reaction container and carry out polymerization reaction for 4 hours; further raise the temperature to 100°C, and apply continuous vacuum to the reaction container at a vacuum degree of ≤-0.09MPa. The reaction time is 5 hours. The organic solvent volatilized or generated during the reaction is collected by a special solvent recovery device to obtain a resin solution.

[0067] S4. The reaction vessel is heated to 250° C., reacted under vacuum for 6 hours, and naturally cooled to obtain a block of component A resin.

[0068] S5. The obtained block resin is mechanically crushed by a pulverizer, and the particle size of the crushed resin is controlled to be 150 mesh-200 mesh to obtain a powdered resin of component A, ie, component A.

[0069] Table 2 Basic properties of component A resin

[0070] Serial number Test items performance 1 Glass transition temperature, °C ＞600 2 Thermal decomposition temperature (5%), ℃ 650 3 Minimum viscosity of resin, Pa.s 0.1

[0071] Preparation Example 3

[0072] This preparation example provides a component B solution, and the preparation method thereof comprises the steps of:

[0073] S1. 2025 g of 4-phenylethynylphthalic anhydride and 1200 g of 2,3,3',4'-biphenyltetracarboxylic dianhydride monomer were dissolved in 4839 g of ethanol, and refluxed at 80° C. for 4 h to obtain an esterification solution with a concentration of 40 wt %.

[0074] S2. 440 g of m-phenylenediamine and 1330 g of diaminophenylcarborane diamine monomer were dissolved in 4138 g of ethanol solvent, and heated to 55° C. under inert gas protection to obtain a diamine solution with a concentration of 30 wt %.

[0075] S3. Pour the above-obtained esterification solution into the diamine solution, raise the temperature to 78°C under stirring in the reaction vessel and carry out polymerization reaction for 4 hours; further raise the temperature to 95°C, and apply continuous vacuum to the reaction vessel at a vacuum degree of ≤-0.09MPa. The reaction time is 6 hours. The organic solvent volatilized or generated during the reaction is collected by a special solvent recovery device to obtain a component B solution with a concentration of 80wt%.

[0076]

[0077] Preparation Example 4

[0078] This preparation example provides a component B solution, and the preparation method thereof comprises the steps of:

[0079] S1. 1434 g of 4-phenylethynylphthalic anhydride and 1699 g of 2,3,3',4'-biphenyltetracarboxylic dianhydride monomers were dissolved in 4699 g of ethanol, and refluxed at 78° C. for 3 h to obtain an esterification solution with a concentration of 40 wt %.

[0080] S2. 925 g of TFMBZ and 943 g of diaminophenylcarborane diamine monomer were dissolved in 4357 g of ethanol solvent, and heated to 45° C. under inert gas protection to obtain a diamine solution with a concentration of 30 wt %.

[0081] S3. Pour the above-obtained esterification solution into the diamine solution, raise the temperature to 70°C under the stirring action of the reaction container and carry out polymerization reaction for 3 hours; further raise the temperature to 100°C, and apply continuous vacuum to the reaction container at the same time, the vacuum degree is ≤-0.09MPa, and the reaction time is 4 hours. The organic solvent volatilized or generated during the reaction is collected by a special solvent recovery device to obtain a B component solution with a concentration of 80wt%.

[0082]

[0083] Preparation Example 5

[0084] This preparation example provides a component B solution, and the preparation method thereof comprises the steps of:

[0085] S1. 1884 g of 4-PEPA and 1117 g of 2,3,3',4'-biphenyltetracarboxylic acid dianhydride monomer were dissolved in 4699 g of ethanol, and refluxed at 78° C. for 4 h to obtain an esterification solution with a concentration of 40 wt %.

[0086] S2. 925 g of 3,4-ODA and 943 g of diaminophenylcarborane diamine monomer were dissolved in 4357 g of ethanol solvent, and heated to 55° C. under inert gas protection to obtain a diamine solution with a concentration of 30 wt %.

[0087] S3. Pour the above-obtained esterification solution into the diamine solution, raise the temperature to 78°C under stirring in the reaction vessel and carry out polymerization reaction for 4 hours; further raise the temperature to 95°C and apply continuous vacuum to the reaction vessel at a vacuum degree of ≤-0.09MPa for 6 hours. The organic solvent volatilized or generated during the reaction is collected by a special solvent recovery device to obtain a B component solution with a concentration of 80wt%.

[0088]

[0089] Example 1

[0090] This embodiment provides a carborane hybrid RTM polyimide resin, and the preparation method thereof comprises the steps of:

[0091] S1. Heat the B component resin solution obtained in Preparation Example 3 to 100°C, add the A component resin powder obtained in Preparation Example 2 thereto, control the content of the A component to 20% of the total of the A component and the B component, first use a high-speed stirring device to stir, control the stirring speed to 4000r / min, then perform ultrasonic oscillation, then heat the above mixture to 250°C, react under vacuum for 6h, and after cooling, obtain blocky carborane hybrid RTM polyimide resins with different amounts of the A component added.

[0092] S2. Mechanically crush the block resin obtained in step S1 to control the particle size of the crushed resin to 50 meshes, thereby obtaining a powdered carborane hybrid RTM polyimide resin.

[0093] Example 2

[0094] This embodiment provides a carborane hybrid RTM polyimide resin, and the preparation method thereof comprises the steps of:

[0095] S1. Heat the B component resin solution obtained in Preparation Example 3 to 100°C, add the A component resin powder obtained in Preparation Example 2 thereto, control the content of the A component to account for 40% of the sum of the A component and the B component, first use a high-speed stirring device to stir, control the stirring speed to 3500r / min, then perform ultrasonic oscillation, then heat the above mixture to 250°C, react under vacuum for 6h, and after cooling, obtain blocky carborane hybrid RTM polyimide resins with different amounts of the A component added.

[0096] S2. Mechanically crush the block resin obtained in step S1 to control the particle size of the crushed resin to 50 meshes, thereby obtaining a powdered carborane hybrid RTM polyimide resin.

[0097] Example 3

[0098] This embodiment provides a carborane hybrid RTM polyimide resin, and the preparation method thereof comprises the steps of:

[0099] S1. The component B resin solution obtained in Preparation Example 3 is heated to 100°C, and the component A resin powder obtained in Preparation Example 2 is added thereto, and the content of component A is controlled to account for 60% of the total of component A and component B. First, a high-speed stirring device is used for stirring, and the stirring speed is controlled to 3500r / min, and then ultrasonic vibration is performed. Then the mixture is heated to 250°C, reacted under vacuum for 6h, and after cooling, blocky carborane hybrid RTM polyimide resins with different amounts of component A added are obtained.

[0100] S2. Mechanically crush the block resin obtained in step S1 to control the particle size of the crushed resin to 50 meshes, thereby obtaining a powdered carborane hybrid RTM polyimide resin.

[0101] Example 4

[0102] This embodiment provides a carborane hybrid RTM polyimide resin, and the preparation method thereof comprises the steps of:

[0103] S1. Heat the B component resin solution obtained in Preparation Example 3 to 100°C, add the A component resin powder obtained in Preparation Example 2 thereto, control the content of the A component to account for 80% of the sum of the A component and the B component, first use a high-speed stirring device to stir, control the stirring speed to 3500r / min, then perform ultrasonic oscillation, then heat the above mixture to 250°C, react under vacuum for 6h, and after cooling, obtain blocky carborane hybrid RTM polyimide resins with different amounts of the A component added.

[0104] S2. Mechanically crush the block resin obtained in step S1 to control the particle size of the crushed resin to 50 meshes, thereby obtaining a powdered carborane hybrid RTM polyimide resin.

[0105] The powdered carborane hybrid RTM polyimide resin obtained in Examples 1-4 was subjected to performance tests, and the results are shown in Table 1.

[0106] Table 1 RTM-1 resin properties

[0107]

[0108] Example 5

[0109] This embodiment provides a carborane hybrid RTM polyimide resin, and the preparation method thereof comprises the steps of:

[0110] S1. Heat the B component resin solution obtained in Preparation Example 4 to 100°C, add the A component resin powder obtained in Preparation Example 2 thereto, control the content of the A component to 20% of the total of the A component and the B component, first use a high-speed stirring device to stir, control the stirring speed to 3500r / min, then perform ultrasonic oscillation, then heat the above mixture to 210°C, react under vacuum for 6h, and after cooling, obtain blocky carborane hybrid RTM polyimide resins with different amounts of the A component added.

[0111] S2. Mechanically crush the block resin obtained in step S1 to control the particle size of the crushed resin to 50 meshes, thereby obtaining a powdered carborane hybrid RTM polyimide resin.

[0112] Example 6

[0113] This embodiment provides a carborane hybrid RTM polyimide resin, and the preparation method thereof comprises the steps of:

[0114] S1. Heat the B component resin solution obtained in Preparation Example 4 to 100°C, add the A component resin powder obtained in Preparation Example 2 thereto, control the content of the A component to account for 40% of the sum of the A component and the B component, first use a high-speed stirring device to stir, control the stirring speed to 3500r / min, then perform ultrasonic oscillation, then heat the above mixture to 210°C, react under vacuum for 6h, and after cooling, obtain blocky carborane hybrid RTM polyimide resins with different amounts of the A component added.

[0115] S2. Mechanically crush the block resin obtained in step S1 to control the particle size of the crushed resin to 50 meshes, thereby obtaining a powdered carborane hybrid RTM polyimide resin.

[0116] Example 7

[0117] This embodiment provides a carborane hybrid RTM polyimide resin, and the preparation method thereof comprises the steps of:

[0118] S1. The component B resin solution obtained in Preparation Example 4 is heated to 100°C, and the component A resin powder obtained in Preparation Example 2 is added thereto, and the content of component A is controlled to account for 60% of the total of component A and component B. First, a high-speed stirring device is used for stirring, and the stirring speed is controlled to 3500r / min, and then ultrasonic vibration is performed. Then the mixture is heated to 210°C, reacted under vacuum for 6h, and after cooling, blocky carborane hybrid RTM polyimide resins with different amounts of component A added are obtained.

[0119] S2. Mechanically crush the block resin obtained in step S1 to control the particle size of the crushed resin to 50 meshes, thereby obtaining a powdered carborane hybrid RTM polyimide resin.

[0120] Example 8

[0121] This embodiment provides a carborane hybrid RTM polyimide resin, and the preparation method thereof comprises the steps of:

[0122] S1. Heat the B component resin solution obtained in Preparation Example 4 to 100°C, add the A component resin powder obtained in Preparation Example 2 thereto, control the content of the A component to account for 80% of the sum of the A component and the B component, first use a high-speed stirring device to stir, control the stirring speed to 3500r / min, then perform ultrasonic oscillation, then heat the above mixture to 210°C, react under vacuum for 6h, and after cooling, obtain blocky carborane hybrid RTM polyimide resins with different amounts of the A component added.

[0123] S2. Mechanically crush the block resin obtained in step S1 to control the particle size of the crushed resin to 50 meshes, thereby obtaining a powdered carborane hybrid RTM polyimide resin.

[0124] The powdered carborane hybrid RTM polyimide resin obtained in Examples 5-8 was subjected to performance tests, and the results are shown in Table 2.

[0125] Table 2 RTM-1 resin properties

[0126]

[0127] Example 9

[0128] This embodiment provides a carborane hybrid RTM polyimide resin, and the preparation method thereof comprises the steps of:

[0129] S1. Heat the B component resin solution obtained in Preparation Example 5 to 100°C, add the A component resin powder obtained in Preparation Example 2 thereto, control the content of the A component to 20% of the total of the A component and the B component, first use a high-speed stirring device to stir, control the stirring speed to 3500r / min, then perform ultrasonic oscillation, then heat the above mixture to 220°C, react under vacuum for 5h, and after cooling, obtain blocky carborane hybrid RTM polyimide resins with different amounts of the A component added.

[0130] S2. Mechanically crush the block resin obtained in step S1 to control the particle size of the crushed resin to 50 meshes, thereby obtaining a powdered carborane hybrid RTM polyimide resin.

[0131] Example 10

[0132] This embodiment provides a carborane hybrid RTM polyimide resin, and the preparation method thereof comprises the steps of:

[0133] S1. Heat the B component resin solution obtained in Preparation Example 5 to 100°C, add the A component resin powder obtained in Preparation Example 2 thereto, control the content of the A component to be 40% of the sum of the A component and the B component, first use a high-speed stirring device to stir, control the stirring speed to 3500r / min, then perform ultrasonic oscillation, then heat the above mixture to 220°C, react under vacuum for 5h, and after cooling, obtain blocky carborane hybrid RTM polyimide resins with different amounts of the A component added.

[0134] S2. Mechanically crush the block resin obtained in step S1 to control the particle size of the crushed resin to 50 meshes, thereby obtaining a powdered carborane hybrid RTM polyimide resin.

[0135] Embodiment 11

[0136] This embodiment provides a carborane hybrid RTM polyimide resin, and the preparation method thereof comprises the steps of:

[0137] S1. Heat the B component resin solution obtained in Preparation Example 5 to 100°C, add the A component resin powder obtained in Preparation Example 2 thereto, control the content of the A component to account for 60% of the sum of the A component and the B component, first use a high-speed stirring device to stir, control the stirring speed to 3500r / min, then perform ultrasonic oscillation, then heat the above mixture to 220°C, react under vacuum for 5h, and after cooling, obtain blocky carborane hybrid RTM polyimide resins with different amounts of the A component added.

[0138] S2. Mechanically crush the block resin obtained in step S1 to control the particle size of the crushed resin to 50 meshes, thereby obtaining a powdered carborane hybrid RTM polyimide resin.

[0139] Example 12

[0140] This embodiment provides a carborane hybrid RTM polyimide resin, and the preparation method thereof comprises the steps of:

[0141] S1. Heat the B component resin solution obtained in Preparation Example 5 to 100°C, add the A component resin powder obtained in Preparation Example 2 thereto, control the content of the A component to account for 80% of the sum of the A component and the B component, first use a high-speed stirring device to stir, control the stirring speed to 3500r / min, then perform ultrasonic oscillation, then heat the above mixture to 220°C, react under vacuum for 5h, and after cooling, obtain blocky carborane hybrid RTM polyimide resins with different amounts of the A component added.

[0142] S2. Mechanically crush the block resin obtained in step S1 to control the particle size of the crushed resin to 50 meshes, thereby obtaining a powdered carborane hybrid RTM polyimide resin.

[0143] The powdered carborane hybrid RTM polyimide resin obtained in Examples 9-12 was subjected to performance tests, and the results are shown in Table 3.

[0144] Table 3 RTM-3 resin properties

[0145]

[0146] It can be concluded from the above embodiments that the present invention can adjust the concentrations of component A and component B, adjust the resin viscosity and open period through component A, and adjust the resin strength and heat resistance through component B, thereby obtaining lower viscosity and longer open period while ensuring high resistance.

[0147] It should be clear that the various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. For the embodiments of the method, the relevant parts can refer to the partial description of the device embodiment (adopted according to the writing situation). In addition, for the sake of brevity, the detailed description of the known method technology is omitted here.

[0148] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A carborane hybrid RTM polyimide resin, characterized in that: The raw materials for preparing the carborane hybrid RTM polyimide resin include component A and component B; The component A comprises a structure shown in formula I: The component B comprises the structure shown in formula II: In formula II, X1 represents any one of the following substituents: n is 0, 1 or 2.

2. The carborane hybrid RTM polyimide resin according to claim 1, characterized in that: The preparation method of component A is: S1.1 dissolving 4-phenylethynylbenzene anhydride in an alcohol solvent to react to obtain an esterification solution; S1.2 dissolving the carborane diamine monomer in an organic solvent, and heating under the protection of an inert gas to obtain a diamine solution; S1.3 mixing the esterification solution with the diamine solution to carry out a polymerization reaction to obtain a resin solution; S1.4 heating the resin solution, reacting it under vacuum, and then cooling it to obtain a block resin containing the compound of formula I; S1.5 The block resin is crushed to obtain component A; The component A is resin powder with a particle size of 50-200 meshes.

3. The carborane hybrid RTM polyimide resin according to claim 2, characterized in that: In step S1.1, the reaction temperature is 60°C-90°C, the reaction time is 1h-4h, and the concentration of the esterification solution obtained by the reaction is 20wt%-80wt%; In step S1.2, the heating temperature is 40° C.-80° C., and the concentration of the diamine solution obtained by heating is 20wt%-80wt%; In step S1.3, the polymerization reaction comprises: pouring the esterification solution into the diamine solution, heating to 60° C.-80° C. under stirring, and performing polymerization reaction for 1 h-5 h; Then, the temperature is raised to 80-120° C., the vacuum degree is controlled to be ≤-0.09 MPa, and the reaction is performed for 1 h-12 h to obtain the resin solution; In step S1.4, the heating temperature is 150°C-260°C, and the reaction time under vacuum is 1h-6h.

4. The carborane hybrid RTM polyimide resin according to claim 1, characterized in that: The preparation method of component B is: S2.1 dissolving 4-phenylethynylphthalic anhydride and 2,3,3',4'-biphenyltetracarboxylic dianhydride monomers in an alcohol solvent, and reacting to obtain an esterification solution; S2.2 dissolving a diamine monomer and a carborane diamine monomer in an organic solvent, and heating under an inert gas to obtain a mixed diamine solution; S2.3 pouring the esterification solution into the mixed diamine solution to carry out polymerization reaction to obtain a resin solution containing the compound of the structure represented by formula II, namely component B.

5. The carborane hybrid RTM polyimide resin according to claim 4, characterized in that: The mass percentage content of the compound of formula II in the component B is 60wt%-90wt%.

6. The carborane hybrid RTM polyimide resin according to claim 4, characterized in that: In step S2.1, the reaction temperature is 60°C-90°C, the reaction time is 1h-6h, and the concentration of the obtained esterification solution is 20wt%-80wt%; In step S2.2, the heating temperature is 40°C-60°C, and the concentration of the mixed diamine solution obtained by heating is 20wt%-80wt%; In step S2.3, the polymerization reaction comprises: pouring the esterification solution into the mixed diamine solution, heating to 60° C.-80° C. under stirring, and performing polymerization reaction for 1 h-5 h; Then raise the temperature to 80-120°C, maintain the vacuum degree ≤-0.09MPa, react for 1h-12h, and obtain component B.

7. The carborane hybrid RTM polyimide resin according to claim 4, characterized in that: The diamine monomer is selected from one or two of m-PDA, 3,4-ODA, TFMBZ, 1,3,4-APB, 4,4-MDA, 4,4-DDS, p-ODA, BAPP, and FDA.

8. A method for preparing a carborane hybrid RTM polyimide resin according to any one of claims 1 to 7, characterized in that: Includes steps: S1. Component B is heated to a first temperature, component A is added thereto, stirred, then ultrasonically treated, then heated to a second temperature, reacted in vacuum, and then cooled to obtain a block of carborane hybrid RTM polyimide resin; S2. crushing the blocky carborane hybrid RTM polyimide resin to obtain a powdery carborane hybrid RTM polyimide resin.

9. The method for preparing the carborane hybrid RTM polyimide resin according to claim 8, characterized in that: The first temperature is 90-120°C, and the second temperature is 150°C-260°C; In step S1, the reaction time of the vacuum reaction is 1h-6h; In step S2, the particle size of the powdered carborane hybrid RTM polyimide resin is ≥20 mesh.

10. The carborane hybrid RTM polyimide resin according to any one of claims 1 to 7 is suitable for RTM, VARTM, VARI and RFI molding processes.

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