A heat-resistant material for repairing composite material products and its application

Abstract

The present application relates to a heat-resistant material for repairing composite material products and its application, belonging to the technical field of pressure vessel materials. The heat-resistant material for repairing composite material products comprises the following components in parts by weight: 80-120 parts of epoxy resin; 20-40 parts of curing agent; 20-30 parts of short-cut quartz fibers; 20-30 parts of vermiculite powder; 15-20 parts of phenolic resin microspheres; 5-10 parts of zirconia; 15-20 parts of low-melting glass powder; 30-40 parts of wet mica powder. The heat-resistant putty product for repairing composite material products prepared from the heat-resistant material for repairing composite material products provided by the solution of the present application has excellent heat-resistant performance, still has good strength and thermal shock crack resistance under high-temperature conditions, and has a low hardness after curing for 2 h, which is suitable for grinding after use, while the hardness is greatly increased after curing for 24 h, and has a good repair effect.

Description

Technical Field

[0001] The present application relates to a heat - resistant material for repairing composite material products and its application, belonging to the technical field of pressure vessel materials. Background Art

[0002] At present, carbon fiber composite high - pressure gas cylinders mostly adopt the wet winding forming process. In the forming process, it is necessary to first prepare an inner liner material with a connecting seat at the head and a smooth tail. The inner liner material can be an alloy material or a composite material. At present, the research on composite material inner liners has attracted much attention, so the research on related composite high - pressure vessels has gradually increased. During the wet winding forming process on the outer side of the inner liner, due to the limitations of the preparation process, the tail of the inner liner is smooth. In order to further carry out winding, it is necessary to additionally fixedly arrange a connecting tail seat. The connecting tail seat cooperates with the head connecting seat formed naturally during the preparation of the inner liner, and can realize the winding of, for example, pre - impregnated carbon fiber composite materials.

[0003] Since most of the inner liner materials in the current prior art are alloy materials, and the connecting tail seat materials matched with them also mostly use alloy materials. In order to adapt to the research direction of composite material inner liners, it is necessary to provide a connecting tail seat material that matches it. In the prior art, the connecting tail seat materials are mostly directly prepared based on the composite material inner liner materials. However, the role played by the connecting tail seat during the winding process requires it to have good tensile and bending properties, which are different from the properties such as hydrogen permeability and shear strength that are mostly focused on for composite material inner liners. At the same time, due to the working conditions of high - pressure gas cylinders, requirements are also put forward for the deformation size of the connecting tail seat under high - temperature and low - temperature conditions.

[0004] During the processing and preparation of the composite material tail seat, the hot - pressing forming process needs to be adopted. Due to the inherent problems of the process, cracks often appear in the processed connecting tail seat products. In order to enable the connecting tail seat with fine cracks to be applied to pressure vessels, it is necessary to repair the connecting tail seat. Since the pressure vessel where the tail seat is located needs to cope with high - temperature environments, the supplementary material for tail seat repair needs to have good heat - resistant performance. And because it is necessary for the operator to manually operate the product to repair the connecting tail seat, it is particularly important to consider its curing time for the convenience of the operator. If the curing time is too short, it is not convenient for the operator to apply and polish later. If the curing time is too long, it will lead to an extended production cycle, and the curing effect is not good, resulting in low hardness of the product. Summary of the Invention

[0005] To solve the above problems, a heat-resistant material for repairing composite material products and its application are provided. The heat-resistant putty product for repairing composite material products prepared from the heat-resistant material provided in this application has excellent heat-resistant performance, specifically manifested as having good strength and thermal shock crack resistance even under high-temperature conditions, being suitable for repairing pressure vessels used under high-temperature conditions, and the prepared putty product has a relatively low hardness after curing for 2 hours, thus being convenient for operators to polish after using the putty, while the hardness of the putty product increases rapidly after curing for 24 hours, having a good repair effect.

[0006] According to one aspect of the present application, a heat-resistant material for repairing composite material products is provided, which includes the following components by weight:

[0007] 80 - 120 parts of epoxy resin;

[0008] 20 - 40 parts of curing agent;

[0009] 20 - 30 parts of short-cut quartz fiber;

[0010] 20 - 30 parts of vermiculite powder;

[0011] 15 - 20 parts of phenolic resin microspheres;

[0012] 5 - 10 parts of zirconia;

[0013] 15 - 20 parts of low-melting glass powder;

[0014] 30 - 40 parts of wet-process mica powder.

[0015] Optionally, the epoxy resin includes AG-80 and AG-90.

[0016] Optionally, the ratio of AG-80 to AG-90 is 1:0.8 - 1.2.

[0017] Optionally, the curing agent includes JH-0420 and TY650.

[0018] Optionally, the weight ratio of JH-0420 to TY650 is 2 - 4:1.

[0019] Optionally, the length of the short-cut quartz fiber is 10 - 20 mm.

[0020] Optionally, the low-melting glass powder is amino-silane modified low-melting glass powder, and the preparation steps of the amino-silane modified low-melting glass powder include the step of cross-linking reaction of an amino-silane coupling agent with the low-melting glass powder under ultraviolet light.

[0021] Optionally, the preparation steps of the amino-silane modified low-melting glass powder specifically include:

[0022] S1. Ultrasonically disperse the low-melting-point glass powder in an organic solvent, and dry to remove the organic solvent.

[0023] S2. Dissolve the amino-silane coupling agent in an organic solvent, add the low-melting-point glass powder obtained in S1, soak and treat, then filter and vacuum dry.

[0024] S3. After irradiating and curing the low-melting-point glass powder obtained in S2 under ultraviolet conditions, the required amino-silane modified low-melting-point glass powder is obtained.

[0025] According to another aspect of the present application, a preparation method of a heat-resistant putty for repairing composite material products is provided. The composition of the heat-resistant putty for repairing composite material products is any of the above-mentioned heat-resistant materials for repairing composite material products. The preparation method includes the following steps:

[0026] S1. Heat, mix and stir the curing agent to obtain a curing agent premix.

[0027] S2. Heat, knead and stir the epoxy resin, add the premixed curing agent, suitable chopped fibers, and vermiculite powder, and then continue to knead and stir.

[0028] S3. Add phenolic resin microspheres, zirconia, low-melting-point glass powder and wet mica powder, and continue to knead and stir.

[0029] S4. Pour the kneaded mixture into a preheated mold for pressure molding, and after cooling, obtain the formed heat-resistant putty for repairing composite material products.

[0030] According to the last aspect of the present application, an application of any of the above-mentioned heat-resistant materials for repairing composite material products or the above-mentioned heat-resistant putty for repairing composite material products in the repair of pressure vessels is provided.

[0031] 1. The heat-resistant material for repairing composite material products provided by the present application, when preparing the putty product, not only has good heat-resistant performance, but also is convenient to use. Specifically, the curing time is appropriate, and the hardness is not high after 2 hours of use, which is convenient for the operator to polish after use, and can quickly cure after 24 hours of use and rapidly reach a high hardness.

[0032] 2. The heat-resistant material for repairing composite material products provided by the present application can significantly improve the thermal shock crack resistance of the putty product by adding modified low-melting-point glass powder. Especially when using amino-silane modified low-melting-point glass powder, the improvement of product performance is the most significant.

[0033] 3. The heat-resistant material for repairing composite material products provided by this application, when the JH-0420 curing agent and the TY650 curing agent are used in combination, can make the hardness of the putty product between 60 and 70 MPa after 2 hours of use, which is convenient for the operator to perform subsequent grinding operations. And it can be quickly cured after 24 hours of use, and achieve a good curing hardness effect.

[0034] 4. The heat-resistant material for repairing composite material products provided by this application uses phenolic resin microspheres, zirconia, low-melting glass powder, wet mica powder, etc. in combination. While improving the strength of the putty product, it can also obtain good heat-resistant performance, meeting the needs of the putty product to repair pressure vessels used under high-temperature conditions.

[0035] 5. The heat-resistant material for repairing composite material products provided by this application has good compatibility with the thermal expansion coefficient of the connecting tailstock, can repair the connecting tailstock well and is applicable to high-temperature conditions. In addition, it also has good heat insulation performance, which enables it not only to be used for repairing the connecting tailstock, but also has the potential to repair the inner liner of composite material pressure vessels, improving the applicability of this repair product. Specific Embodiments

[0036] The following details this application in combination with embodiments, but this application is not limited to these embodiments. Unless otherwise specified, the raw materials and catalysts in the embodiments of this application are all purchased through commercial channels.

[0037] Example 1 Preparation of Amino-Silane Modified Low-Melting Glass Powder

[0038] 1) Pretreatment of low-melting glass powder: Use bismuth oxide borosilicate series low-melting glass powder with a particle size controlled at 5 - 10 μm; ultrasonically disperse in acetone for 20 minutes to remove surface impurities, and dry at 120 °C for 8 hours to remove acetone;

[0039] 2) Preparation of amino-silane coupling agent: Select 3-aminopropyltrimethoxysilane coupling agent and prepare it into a 2% volume fraction solution in ethanol solution;

[0040] 3) Coating of silane coupling agent: Immerse the pretreated glass powder in the coupling agent ethanol solution for 5 hours, take it out and filter, and vacuum dry at 110 °C for 8 hours to adhere the coupling agent;

[0041] 4) Ultraviolet curing reaction: Irradiate the glass powder with the coupling agent coating in an ultraviolet irradiation box for 30 minutes to cause the coupling agent to undergo a cross-linking reaction and cure on the surface of the glass powder to obtain this amino-silane modified low-melting glass powder.

[0042] Example 2

[0043] A heat-resistant material for repairing composite material products includes the following components by weight:

[0044] 100 parts of epoxy resin (50 parts of AG-80 and 50 parts of AG-90);

[0045] 30 parts of curing agent (7.5 parts of TY650 and 22.5 parts of JH-0420);

[0046] 25 parts of short-cut quartz fiber (10 - 20 mm);

[0047] 25 parts of vermiculite powder;

[0048] 16 parts of THC-389 phenolic resin microspheres;

[0049] 8 parts of zirconia;

[0050] 18 parts of low-melting-point glass powder (amino-silane modified low-melting-point glass powder prepared in Example 1);

[0051] 35 parts of wet mica powder.

[0052] The steps for preparing a heat-resistant putty for repairing composite material products using the composite material product are as follows:

[0053] 0) Preparation of components: Weigh each component according to the above weight parts for standby;

[0054] 1) Premixing of curing agent: Add the curing agent to a three-necked flask, heat to 80 °C, mix and stir for 0.5 hour to obtain a curing agent premix;

[0055] 2) Kneading of putty matrix: Add 100 parts of epoxy resin to the kneading tank of an internal mixer, turn on the heating device, control the temperature at 120 °C, and at the same time knead and stir, and sequentially add the premixed curing agent, short-cut quartz fiber, and vermiculite powder; Knead for 2 hours, cool to room temperature, and remove air bubbles;

[0056] 3) Adding fillers and reinforcing phases: Add phenolic resin microspheres, zirconia, low-melting-point glass powder, and wet mica powder to the matrix, and continue to knead for 1 hour to fully disperse each component;

[0057] 4) Internal mixing and molding: Pour the kneaded mixture into a preheated mold, perform pressure molding on a press, control the mold temperature at 130 °C, set the pressure at 10 MPa, and after cooling to room temperature, a formed heat-resistant composite putty product is obtained.

[0058] Example 3

[0059] A heat-resistant material for repairing composite material products, comprising the following components by weight parts:

[0060] 80 parts of epoxy resin (44.4 parts of AG-80 and 35.6 parts of AG-90);

[0061] 20 parts of curing agent (4 parts of TY650 and 16 parts of JH-0420);

[0062] 20 parts of chopped quartz fiber (10 - 20 mm);

[0063] 20 parts of vermiculite powder;

[0064] 15 parts of THC-389 phenolic resin microspheres;

[0065] 5 parts of zirconia;

[0066] 15 parts of low melting point glass powder (amino-silane modified low melting point glass powder prepared in Example 1);

[0067] 30 parts of wet mica powder.

[0068] The steps for preparing a heat-resistant putty for repairing composite material products using the composite material product are as follows:

[0069] 0) Preparation of components: Weigh each component according to the above weight parts for standby;

[0070] 1) Premixing of curing agent: Add the curing agent to a three-necked flask, heat to 80 °C, mix and stir for 0.5 hours to obtain a curing agent premix;

[0071] 2) Kneading of putty matrix: Add 100 parts of epoxy resin to the kneading cylinder of an internal mixer, turn on the heating device, control the temperature at 120 °C, and at the same time knead and stir, and sequentially add the premixed curing agent, chopped quartz fiber, and vermiculite powder; Knead for 2 hours, cool to room temperature, and remove air bubbles;

[0072] 3) Adding fillers and reinforcing phases: Add phenolic resin microspheres, zirconia, low melting point glass powder, and wet mica powder to the matrix, and continue kneading for 1 hour to fully disperse each component;

[0073] 4) Internal mixing and molding: Pour the kneaded material into a preheated mold, perform pressure molding on a press, control the mold temperature at 130 °C, set the pressure at 10 MPa, and after cooling to room temperature, a heat-resistant composite putty product is obtained.

[0074] Example 4

[0075] A heat-resistant material for repairing composite material products, comprising the following components by weight parts:

[0076] 120 parts of epoxy resin (54.5 parts of AG-80 and 65.5 parts of AG-90);

[0077] 40 parts of curing agent (13.3 parts of TY650 and 26.7 parts of JH-0420);

[0078] 30 parts of short-cut quartz fibers (10 - 20 mm);

[0079] 30 parts of vermiculite powder;

[0080] 20 parts of THC-389 phenolic resin microspheres;

[0081] 10 parts of zirconia;

[0082] 20 parts of low melting point glass powder (amino-silane modified low melting point glass powder prepared in Example 1);

[0083] 40 parts of wet mica powder.

[0084] The steps for preparing a heat-resistant putty for repairing composite material products using the composite material product are as follows:

[0085] 0) Preparation of components: Weigh each component according to the above weight parts for standby;

[0086] 1) Premixing of curing agent: Add the curing agent into a three-necked flask, heat to 80 °C, mix and stir for 0.5 hour to obtain a curing agent premix;

[0087] 2) Kneading of putty matrix: Add 100 parts of epoxy resin into the kneading tank of an internal mixer, turn on the heating device, control the temperature at 120 °C, and at the same time knead and stir, and sequentially add the premixed curing agent, short-cut quartz fibers, and vermiculite powder; Knead for 2 hours, cool to room temperature, and remove air bubbles;

[0088] 3) Adding fillers and reinforcing phases: Add phenolic resin microspheres, zirconia, low melting point glass powder, and wet mica powder to the matrix, and continue kneading for 1 hour to fully disperse each component;

[0089] 4) Internal mixing and molding: Pour the kneaded material into a preheated mold, perform pressure molding on a press, control the mold temperature at 130 °C, set the pressure at 10 MPa, and after cooling to room temperature, a heat-resistant composite putty product is obtained.

[0090] Example 5

[0091] This example is basically the same as Example 1, except that unmodified low melting point glass powder is used in this example.

[0092] Example 6

[0093] This example is basically the same as Example 1, except that the low melting point glass powder modified with silane coupling agent is used in this example, and the silane coupling agent used in the preparation process is vinyl silane coupling agent.

[0094] Example 7

[0095] This example is basically the same as Example 1, except that the low melting point glass powder modified with silane coupling agent is used in this example, and the silane coupling agent used in the preparation process is siloxane coupling agent.

[0096] Example 8

[0097] This example is basically the same as Example 1, except that the low melting point glass powder modified with silane coupling agent is used in this example, and the silane coupling agent used in the preparation process is chlorosilane coupling agent.

[0098] Example 9

[0099] This example is basically the same as Example 1, except that AG-80 is replaced with an equal amount of AG-90.

[0100] Example 10

[0101] This example is basically the same as Example 1, except that AG-90 is replaced with an equal amount of AG-80.

[0102] Example 11

[0103] This example is basically the same as Example 1, except that JH-0420 is replaced with an equal amount of TY650.

[0104] Example 12

[0105] This example is basically the same as Example 1, except that TY650 is replaced with an equal amount of JH-0420.

[0106] Comparative Example 1

[0107] This comparative example is basically the same as Example 1, except that the phenolic resin microspheres of THC-389 are replaced with an equal amount of zirconia.

[0108] Comparative Example 2

[0109] This comparative example is basically the same as Example 1, except that the wet mica powder is replaced with an equal amount of zirconia.

[0110] Comparative Example 3

[0111] This comparative example is basically the same as Example 1, except that the low melting point glass powder is replaced with an equal amount of zirconia.

[0112] Test Example 1 Heat Resistance Test

[0113] In this test example, the heat-resistant putty for repairing the composite material products obtained in the above-mentioned examples and comparative examples was tested for heat-resistant performance. The tests included heat insulation performance, high-temperature tensile performance, and thermal shock crack resistance performance. Among them, the heat insulation performance test used the heat flow method to measure the thermal conductivity of the sample to evaluate the heat insulation performance. The high-temperature tensile performance was tested by a standard tensile test in a high-temperature chamber to measure the tensile strength of the material at 250°C. The thermal shock crack resistance performance was tested by a thermal fatigue test, loading at 250°C and unloading during cooling, cycling until cracks appeared, recording the number of cycles, with 100 cycles per week and observing whether cracks appeared at weekly intervals. The test results are shown in Table 1 below.

[0114] Table 1 Test Results of Heat-Resistant Performance

[0115] Number Heat insulation performance (W / m·K) High-temperature tensile strength (MPa) Thermal shock crack resistance (times) Example 2 0.22 35 1900～2000 Example 3 0.27 34 1800～1900 Example 4 0.24 36 1900～2000 Example 5 0.32 23 1100～1200 Example 6 0.24 25 1100～1200 Example 7 0.26 23 1200～1300 Example 8 0.31 28 1000～1100 Example 9 0.45 36 1800～1900 Example 10 0.52 30 1400～1500 Example 11 0.21 34 1800～1900 Example 12 0.25 36 1900～2000 Comparative Example 1 0.23 34 1500～1600 Comparative Example 2 0.36 33 800～900 Comparative Example 3 0.29 32 600～700

[0116] Test Example 2 Curing Time and Hardness Test

[0117] In this test example, the heat-resistant putty for repairing the composite material products obtained in the above-mentioned examples and comparative examples was tested for curing time and hardness. The curing time and the hardness after 2 hours of use and the hardness after 24 hours of use were tested. Among them, the hardness test obtained the compressive strength of the product through a compression experiment to characterize its internal hardness. The test results are shown in Table 1 below.

[0118] Table 2 Test Results of Curing Time and Hardness

[0119] Number Curing time (h) Hardness after 2 h of use (MPa) Hardness after 24 h of use (MPa) Example 2 37 65 143 Example 3 37 64 139 Example 4 36 63 142 Example 5 34 62 105 Example 6 35 64 123 Example 7 36 68 131 Example 8 35 62 102 Example 9 35 50 151 Example 10 37 74 132 Example 11 46 54 95 Example 12 27 83 130 Comparative Example 1 36 65 127 Comparative Example 2 35 62 118 Comparative Example 3 38 64 124

[0120] According to the results in Table 1 and Table 2, it can be seen that the putty products obtained in Examples 2, 3, and 4 of this application not only have good heat-resistant performance but also are convenient to use. Specifically, the curing time is appropriate, the hardness is not high after 2 hours of use, which is convenient for the operator to polish after use, and it can be quickly cured and reach a relatively high hardness after 24 hours of use.

[0121] According to the results of Examples 1, 5, 6, 7, 8 and Comparative Example 3, in the solution of this application, by adding modified low-melting glass powder, the thermal shock crack resistance performance of the putty product can be significantly improved. Especially when using amino-silane modified low-melting glass powder, the improvement of the product performance is the most significant.

[0122] According to the results of Examples 1, 9, and 10, when AG-80 epoxy resin and AG-90 epoxy resin are synergistically combined, they can achieve an unexpected synergistic compatibility effect when improving the heat insulation performance of the putty product. When the two are combined with each other, better heat insulation performance can be obtained.

[0123] According to the results of Examples 1, 11, and 12, in the solution of the present application, when the curing agent JH-0420 is used in combination with the curing agent TY650, the hardness of the putty product can be between 60 and 70 MPa after 2 hours of use, which is convenient for the operator to perform subsequent grinding operations. After 24 hours of use, it can be quickly cured and achieve a good curing hardness effect.

[0124] Test Example 3 Thermal Expansion Coefficient Compatibility

[0125] In this test example, the thermal expansion coefficient compatibility of the putty products of the test examples and comparative examples with the following connecting tailstock materials was tested. The connecting tailstock materials include the following raw material components in parts by weight: 80-120 parts of epoxy resin, 25-35 parts of short-cut quartz fibers, 10-20 parts of boron nitride nanosheets, 3-10 parts of curing agent, 1-3 parts of single-walled carbon nanotubes, 0.2-0.5 parts of phosphoric acid, and 50-70 parts of organic solvent. The thermal expansion coefficient was tested using a thermomechanical analyzer (TMA) in the temperature range of 100°C to 200°C with a heating rate of 10°C / min and tested according to ASTM E831 standard. The test results are shown in Table 3 below.

[0126] Table 3 Thermal Expansion Coefficient Results

[0127]

[0128]

[0129] According to the results in Table 3, the thermal expansion coefficient of the solution of the present application is relatively close to that of the connecting tailstock. In particular, the thermal expansion compatibility of Examples 2, 3, and 4 with the connecting tailstock is very good, enabling the heat-resistant material for repairing composite products to better repair the connecting tailstock and adapt to the application of the connecting tailstock under high-temperature conditions.

[0130] As described above, only the embodiments of the present application are given. The protection scope of the present application is not limited by these specific embodiments, but is determined by the claims of the present application. For those skilled in the art, various changes and modifications can be made to the present application. Any modification, equivalent replacement, improvement, etc. made within the technical idea and principle of the present application shall be included within the protection scope of the present application.

Claims

1. Application of a heat-resistant putty for repairing composite products in repairing a connection tailstock of a pressure vessel, characterized in that: The connecting tailstock material comprises the following raw material components in parts by weight: 80-120 parts of epoxy resin, 25-35 parts of quartz chopped fibers, 10-20 parts of boron nitride nanosheets, 3-10 parts of curing agent, 1-3 parts of single-walled carbon nanotubes, 0.2-0.5 parts of phosphoric acid, and 50-70 parts of organic solvent; The components of the heat-proof putty for repairing composite products include the following components by weight: 80-100 parts of epoxy resin, 20-30 parts of curing agent, 20-25 parts of quartz chopped fibers, 20-25 parts of vermiculite powder, 15-16 parts of phenolic resin microspheres, 5-8 parts of zirconium dioxide, 15-18 parts of low-melting-point glass powder, and 30-35 parts of wet-process mica powder, wherein the epoxy resin includes AG-80 and AG-90, and the ratio of AG-80 to AG-90 is 1:0.8-1.0; the curing agent includes JH-0420 and TY65 ... The weight ratio of JH-0420 and TY650 is 2 to 3:1, the length of the quartz chopped fibers is 10 to 20 mm, the low-melting glass powder is aminosilane-modified low-melting glass powder, and the preparation steps of the aminosilane-modified low-melting glass powder include: S1, ultrasonically dispersing the low-melting glass powder in an organic solvent, and drying to remove the organic solvent; S2, dissolving an aminosilane coupling agent in an organic solvent, adding the low-melting glass powder obtained in S1, filtering after soaking treatment, and vacuum drying; S3, curing the low-melting glass powder obtained in S2 under ultraviolet conditions to obtain the desired aminosilane-modified low-melting glass powder.

Images