A high-strength fiber composite material and its preparation method

Abstract

The present invention discloses a high-strength fiber composite material and a preparation method thereof, belonging to the field of fiber composite material technology. The fiber composite material comprises the following raw materials, calculated by weight percentage: 40-50% epoxy resin, 10-15% polyacrylate, 2-3% isocyanate crosslinking agent, 5-9% curing agent, 23-30% modified carbon fiber, and 6-12% ultra-high molecular weight polyethylene fiber. The raw materials are mixed, electrospun, and heat-treated to obtain the fiber composite material. The high-strength fiber composite material of the present invention has good rigidity and toughness, and its overall performance is also improved.

Description

Technical Field

[0001] The invention relates to a high-strength fiber composite material and a preparation method thereof, belonging to the technical field of fiber composite materials. Background Art

[0002] Fiber composite materials are generally composed of a resin-based polymer as a matrix and glass fiber, carbon fiber, and aramid fiber as reinforcing fibers. Epoxy resin fiber composite materials are one of the most common fiber composite materials and are widely used in the preparation of sports equipment. However, due to the high crosslinking density of epoxy resin, it is affected by the restricted molecular chain movement and stress concentration effect, resulting in the resin being brittle and having poor toughness. As a result, this type of resin-based fiber composite material is prone to delamination or brittle fracture when subjected to impact or load changes, resulting in a decrease in the overall performance of the composite material and being limited in applications with high toughness and high impact resistance. In addition, since the carbon fiber is in the resin matrix, it is affected by the surface properties of the carbon fiber and the viscosity of the resin, resulting in poor wettability and dispersibility, which reduces the interfacial bonding force and causes a decrease in the overall performance of the composite material. Summary of the Invention

[0003] To address at least one problem existing in the above-mentioned prior art, the present invention provides a high-strength fiber composite material and a preparation method thereof. The high-strength fiber composite material has good rigidity and toughness, and its overall performance is also improved.

[0004] In order to achieve the above-mentioned purpose, the present invention adopts the following technical solution: a high-strength fiber composite material, calculated by weight percentage, including the following raw materials: 40-50% epoxy resin, 10-15% polyacrylate, 2-3% isocyanate crosslinking agent, 5-9% curing agent, 23-30% modified carbon fiber, and 6-12% ultra-high molecular weight polyethylene fiber.

[0005] Preferably, the high-strength fiber composite material includes the following raw materials, calculated by weight percentage: 44% epoxy resin, 12% polyacrylate, 2.5% isocyanate crosslinking agent, 7.5% curing agent, 26% modified carbon fiber, and 8% ultra-high molecular weight polyethylene fiber.

[0006] Preferably, the modified carbon fiber is carbon fiber that is oxidized to form a surface containing carboxyl groups, and then grafted with a vinyl-containing silane coupling agent.

[0007] Preferably, the preparation process of the modified carbon fiber is as follows:

[0008] (1) Add carbon fiber to concentrated sulfuric acid, ultrasonically treat, and then perform surface oxidation treatment. Then filter and wash with water until neutral, and vacuum dry to obtain carbon fiber containing carboxyl groups.

[0009] (2) The carbon fiber containing carboxyl groups is soaked in acetone, ultrasonically treated, and then grafted. The carbon fiber is filtered and washed with acetone, and then vacuum-dried to obtain the modified carbon fiber.

[0010] Preferably, the ratio of carbon fiber mass to concentrated sulfuric acid volume is 1 g: (100-110) ml.

[0011] Preferably, the ratio of the carbon fiber mass to the volume of the vinyl-containing silane coupling agent and the volume of acetone is 1 g:0.4 ml:(40-50) ml.

[0012] Preferably, the vinyl-containing silane coupling agent is, but not limited to, one of vinyltrimethoxysilane, vinyltriethoxysilane or methylvinyldiethoxysilane, preferably vinyltrimethoxysilane.

[0013] Preferably, the isocyanate cross-linking agent is, but not limited to, one of hexamethylene diisocyanate, toluene diisocyanate or dicyclohexylmethane-4,4'-diisocyanate, preferably hexamethylene diisocyanate.

[0014] Preferably, the curing agent is, but not limited to, one of diaminodiphenylmethane or 4,4'-diaminodicyclohexylmethane, preferably diaminodiphenylmethane.

[0015] Preferably, the epoxy resin is a liquid epoxy resin composed of dicyclohexane acetal and polyhydroxy polyether.

[0016] The present invention also provides a method for preparing a high-strength fiber composite material, comprising the following steps:

[0017] S1. According to the weight percentage of the raw materials, the epoxy resin and the polyacrylate are stirred and mixed to obtain a resin solution;

[0018] S2. Immersing the modified carbon fiber and the ultra-high molecular weight polyethylene fiber in the resin mixture according to the weight percentage of the raw materials, and stirring and mixing them uniformly to obtain a resin mixture;

[0019] S3, adding an isocyanate crosslinking agent and a curing agent to the resin mixture according to the weight percentage of the raw materials, stirring and mixing them uniformly, and degassing to obtain a blended spinning solution;

[0020] S4. The blended spinning solution is subjected to electrostatic spinning and then thermally cross-linked to obtain a high-strength fiber composite material.

[0021] Preferably, the stirring speed is 250-300 rpm.

[0022] Preferably, the temperature of the thermal crosslinking treatment is 110-120° C., and the time is 2-3 hours.

[0023] Preferably, the voltage of electrospinning is 45-50 kV.

[0024] The beneficial effects of the present invention are as follows: 1. The resin fiber composite material of the present invention has good rigidity and toughness, and its strength is greatly improved; 2. The present invention adopts modified carbon fibers whose surfaces are oxidized to form surfaces containing carboxyl groups and grafted with vinyl silane coupling agents, so that the surface activity of the carbon fibers is further promoted to improve the compatibility between the fibers and the resin, and enhance the bonding strength between the fibers and the resin, so that the resin composite material has higher strength and stability; 3. The present invention adopts polyacrylate and epoxy resin blending and combining, through the action of suitable cross-linking agents and curing agents, to reduce the internal stress of the epoxy resin during curing, improve the toughness of the epoxy resin, and form a tighter cross-linked network structure, further enhance the interfacial bonding strength between the epoxy resin and the fiber, and improve the strength and structural stability of the resin fiber composite material; 4. The present invention helps to improve the wetting and bonding ability between the fiber and the resin matrix by compounding the composite fiber composed of modified carbon fiber and ultra-high molecular weight polyethylene fiber with the resin main body, and the lightweight and high strength of the resin fiber composite material is further optimized, and its wear resistance and cut resistance are improved, and its service life is extended. DETAILED DESCRIPTION

[0025] The following is a clear and complete description of the technical solutions in the implementation of the present invention. The described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative work are within the scope of protection of the present invention. If specific conditions are not specified in the embodiments, they are carried out according to conventional conditions or the conditions recommended by the manufacturer. If the manufacturer of the reagents, instruments, and components is not specified, they are all conventional products that can be purchased commercially.

[0026] The epoxy resin in the present invention is a liquid epoxy resin composed of dicyclohexane acetal and polyhydroxy polyether.

[0027] The ultra-high molecular weight polyethylene fibers in the present invention are short-cut ultra-high molecular weight polyethylene fibers with a diameter of 20 to 50 nm.

[0028] The carbon fibers in the present invention are chopped carbon fibers with a diameter of 100 nm to 20 nm.

[0029] Example 1

[0030] A high-strength fiber composite material, comprising the following raw materials, calculated by weight percentage: 40% epoxy resin, 10% polyacrylate, 2% hexamethylene diisocyanate, 6% diaminodiphenylmethane, 30% modified carbon fiber, and 12% ultra-high molecular weight polyethylene fiber;

[0031] The specific preparation method of the high-strength fiber composite material is as follows:

[0032] Step 1: Preparation of modified carbon fiber: 35g of carbon fiber was added to 3500ml of concentrated sulfuric acid, ultrasonically treated at a frequency of 65KHz for 15min, and then surface oxidized at a temperature of 55°C and a speed of 350rpm for 30min, then filtered and washed with water until neutral, and vacuum dried at 75°C to obtain carbon fiber containing carboxyl groups; then the carbon fiber containing carboxyl groups was soaked in 1400ml of acetone, and 14ml of vinyltrimethoxysilane was added, ultrasonically treated at a frequency of 65KHz for 25min, and then grafted at a temperature of 65°C and a speed of 350rpm for 4.5h, then filtered and washed with acetone, and vacuum dried at 75°C to obtain modified carbon fiber;

[0033] Step 2: First, stir and mix 40g of epoxy resin and 10g of polyacrylate at a speed of 250rpm to obtain a resin solution;

[0034] Step 3: Immerse 30 g of modified carbon fiber and 12 g of ultra-high molecular weight polyethylene fiber in the resin mixture, and stir and mix them evenly at a speed of 250 rpm to obtain a resin mixture;

[0035] Step 4: Add 2 g of hexamethylene diisocyanate and 6 g of diaminodiphenylmethane to the resin mixture, stir and mix them evenly at a speed of 250 rpm, and degas to obtain a blended spinning solution;

[0036] Step 5: The blended spinning solution was subjected to electrospinning at a voltage of 45 KV, and then subjected to thermal cross-linking treatment at 110° C. for 3 h to obtain a high-strength fiber composite material.

[0037] Example 2

[0038] A high-strength fiber composite material, comprising the following raw materials, calculated by weight percentage: 40% epoxy resin, 15% polyacrylate, 2% hexamethylene diisocyanate, 7% diaminodiphenylmethane, 26% modified carbon fiber, and 10% ultra-high molecular weight polyethylene fiber;

[0039] The preparation method of the high-strength fiber composite material in Example 2 is the same as that in Example 1, and the raw materials are weighed according to the weight percentages in Example 2.

[0040] Example 3

[0041] A high-strength fiber composite material, comprising the following raw materials, calculated by weight percentage: 47% epoxy resin, 12% polyacrylate, 3% hexamethylene diisocyanate, 9% diaminodiphenylmethane, 23% modified carbon fiber, and 6% ultra-high molecular weight polyethylene fiber;

[0042] The preparation method of the high-strength fiber composite material in Example 3 is the same as that in Example 1, and the raw materials are weighed according to the weight percentages in Example 3.

[0043] Example 4

[0044] A high-strength fiber composite material, calculated by weight percentage, comprising the following raw materials: 50% epoxy resin, 10% polyacrylate, 2.5% hexamethylene diisocyanate, 5% diaminodiphenylmethane, 25% modified carbon fiber, and 7.5% ultra-high molecular weight polyethylene fiber;

[0045] The preparation method of the high-strength fiber composite material in Example 4 is the same as that in Example 1, and the raw materials are weighed according to the weight percentages in Example 4.

[0046] Example 5

[0047] A high-strength fiber composite material, comprising the following raw materials, calculated by weight percentage: 44% epoxy resin, 12% polyacrylate, 2.5% hexamethylene diisocyanate, 7.5% diaminodiphenylmethane, 26% modified carbon fiber, and 8% ultra-high molecular weight polyethylene fiber;

[0048] The preparation method of the high-strength fiber composite material in Example 5 is the same as that in Example 1, and the raw materials are weighed according to the weight percentages in Example 6.

[0049] Example 6

[0050] A high-strength fiber composite material, calculated by weight percentage, comprising the following raw materials: 40% epoxy resin, 10% polyacrylate, 2% toluene diisocyanate, 6% 4,4'-diaminodicyclohexylmethane, 30% modified carbon fiber, and 12% straight ultra-high molecular weight polyethylene fiber;

[0051] The specific preparation method of the high-strength fiber composite material is as follows:

[0052] Step 1: Preparation of modified carbon fiber: 35g of carbon fiber was added to 3850ml of concentrated sulfuric acid, ultrasonically treated at a frequency of 70KHz for 20min, and then surface oxidized at a temperature of 50°C and a speed of 400rpm for 40min, then filtered and washed with water until neutral, and vacuum dried at 75°C to obtain carbon fiber containing carboxyl groups; then the carbon fiber containing carboxyl groups was soaked in 1750ml of acetone, and 14ml of vinyltriethoxysilane was added, ultrasonically treated at a frequency of 70KHz for 30min, and then grafted at a temperature of 60°C and a speed of 400rpm for 4h, then filtered and washed with acetone, and vacuum dried at 75°C to obtain modified carbon fiber;

[0053] Step 2: First, 40g of epoxy resin and 10g of polyacrylate were stirred and mixed at a speed of 300rpm to obtain a resin solution;

[0054] Step 3: Immerse 30 g of modified carbon fiber and 12 g of ultra-high molecular weight polyethylene fiber in the resin mixture, and stir and mix them at a speed of 300 rpm to obtain a resin mixture;

[0055] Step 4: Add 2 g of hexamethylene diisocyanate and 6 g of diaminodiphenylmethane to the resin mixture, stir and mix them evenly at a speed of 300 rpm, and degas to obtain a blended spinning solution;

[0056] Step 5: The blended spinning solution is subjected to electrostatic spinning at a voltage of 50 KV, and then subjected to thermal cross-linking treatment at 120° C. for 2 h to obtain a high-strength fiber composite material.

[0057] Example 7

[0058] A high-strength fiber composite material, calculated by weight percentage, comprising the following raw materials: 40% epoxy resin, 10% polyacrylate, 2% dicyclohexylmethane-4,4'-diisocyanate, 6% diaminodiphenylmethane, 30% modified carbon fiber, and 12% ultra-high molecular weight polyethylene fiber;

[0059] The specific preparation method of the high-strength fiber composite material is as follows:

[0060] Step 1: Preparation of modified carbon fiber: 35g of carbon fiber with a diameter of 100g was added to 3650ml of concentrated sulfuric acid, ultrasonically treated at a frequency of 60KHz for 15min, and then surface oxidized at a temperature of 60°C and a speed of 375rpm for 35min, then filtered and washed with water until neutral, and vacuum dried at 75°C to obtain carbon fiber containing carboxyl groups; then the carbon fiber containing carboxyl groups was soaked in 1570ml of acetone, and 14ml of methylvinyldiethoxysilane was added, ultrasonically treated at a frequency of 60KHz for 25min, and then grafted at a temperature of 70°C and a speed of 400rpm for 5h, then filtered and washed with acetone, and vacuum dried at 75°C to obtain modified carbon fiber;

[0061] Step 2: First, stir and mix 40g of epoxy resin and 10g of polyacrylate at a speed of 275rpm to obtain a resin solution;

[0062] Step 3: Immerse 30 g of modified carbon fiber and 12 g of ultra-high molecular weight polyethylene fiber in the resin mixture, and stir and mix them evenly at a speed of 275 rpm to obtain a resin mixture;

[0063] Step 4: Add 3 g of hexamethylene diisocyanate and 6 g of diaminodiphenylmethane to the resin mixture, stir and mix uniformly at a speed of 275 rpm, and degas to obtain a blended spinning solution;

[0064] Step 5: The blended spinning solution was subjected to electrospinning at a voltage of 48 KV, and then subjected to thermal cross-linking treatment at 115° C. for 2.5 h to obtain a high-strength fiber composite material.

[0065] Comparative Example 1

[0066] A high-strength fiber composite material, wherein the raw materials and weight parts are the same as those in Example 1, except that the modified fiber is replaced by carbon fiber.

[0067] The preparation method of the high-strength fiber composite material in Comparative Example 1 is partially the same as that in Example 1, except that step 1 is not included, and the carbon fiber in step 2 replaces the modified fiber.

[0068] Comparative Example 2

[0069] A high-strength fiber composite material, the raw materials and weight parts are the same as those in Example 1;

[0070] The preparation method of the high-strength fiber composite material of Comparative Example 2 is partially the same as that of Example 1, except that: Step 1: 35 g of chopped carbon fiber with a diameter of 0.1~1 μm is added to 3500 ml of concentrated sulfuric acid, ultrasonically treated at a frequency of 65 kHz for 15 minutes, and then surface oxidized at a temperature of 55°C and a rotation speed of 350 rpm for 30 minutes. After filtering and washing with water until neutral, vacuum drying at 75°C is performed to obtain modified carbon fiber.

[0071] Comparative Example 3

[0072] A high-strength fiber composite material, the raw materials and weight parts are the same as those in Example 1;

[0073] The preparation method of the high-strength fiber composite material of Comparative Example 3 is partially the same as that of Example 1, except that: Step 1: Preparation of modified carbon fiber: 35 g of carbon fiber was added to 1400 mL of hydrogen peroxide with a solubility of 30% by mass, and ultrasonically treated at a frequency of 65 kHz for 30 min, and then surface-oxidized at a temperature of 55 ° C and a speed of 350 rpm for 30 min, then filtered and washed with water until neutral, and vacuum-dried at 75 ° C to obtain a carbon fiber containing hydroxyl groups; then the carbon fiber containing hydroxyl groups was soaked in 1400 ml of acetone, and 14 ml of vinyltrimethoxysilane was added, and ultrasonically treated at a frequency of 65 kHz for 25 min, and then grafted at a temperature of 65 ° C and a speed of 350 rpm for 4.5 h, then filtered and washed with acetone, and vacuum-dried at 75 ° C to obtain a modified carbon fiber;

[0074] Comparative Example 4

[0075] A high-strength fiber composite material, calculated by weight percentage, comprising the following raw materials: 50% epoxy resin, 2% hexamethylene diisocyanate, 6% diaminodiphenylmethane, 30% modified carbon fiber, and 12% ultra-high molecular weight polyethylene fiber;

[0076] The preparation method of the high-strength fiber composite material of Comparative Example 4 is partially the same as that of Example 1, except that:

[0077] Step 2: Immerse 30 g of modified carbon fiber and 12 g of ultra-high molecular weight polyethylene fiber in 50 g of epoxy resin and stir and mix them evenly at a speed of 250 rpm to obtain a resin mixture;

[0078] Step 3: Add 6 g of hexamethylene diisocyanate and 2 g of diaminodiphenylmethane to the resin mixture, stir and mix them evenly at a speed of 250 rpm, and degas to obtain a blended spinning solution;

[0079] Step 4: The blended spinning solution is subjected to electrostatic spinning at a voltage of 45 KV, and then subjected to thermal cross-linking treatment at 110° C. for 3 h to obtain a high-strength fiber composite material.

[0080] Comparative Example 5

[0081] A high-strength fiber composite material, calculated by weight percentage, comprising the following raw materials: 50% epoxy resin, 8% diaminodiphenylmethane, 30% modified carbon fiber, and 12% ultra-high molecular weight polyethylene fiber;

[0082] The preparation method of the high-strength fiber composite material of Comparative Example 5 is partially the same as that of Example 1, except that:

[0083] Step 2: Immerse 30 g of modified carbon fiber and 12 g of ultra-high molecular weight polyethylene fiber in 50 g of epoxy resin and stir and mix them evenly at a speed of 250 rpm to obtain a resin mixture;

[0084] Step 3: 8 g of diaminodiphenylmethane was added to the resin mixture, and the mixture was stirred at a speed of 250 rpm to mix uniformly, and deaerated to obtain a blended spinning solution;

[0085] Step 4: The blended spinning solution is subjected to electrostatic spinning at a voltage of 45 KV, and then subjected to thermal cross-linking treatment at 110° C. for 3 h to obtain a high-strength fiber composite material.

[0086] Comparative Example 6

[0087] A high-strength fiber composite material, calculated by weight percentage, comprising the following raw materials: 40% epoxy resin, 10% polyacrylate, 2% hexamethylene diisocyanate, 6% diaminodiphenylmethane, and 42% modified carbon fiber;

[0088] The preparation method of the high-strength fiber composite material of Comparative Example 6 is partially the same as that of Example 1, except that:

[0089] Step 3: Immerse 42 g of modified carbon fiber in the resin solution and stir and mix evenly at a rotation speed of 250 rpm to obtain a resin mixture.

[0090] Comparative Example 7

[0091] A high-strength fiber composite material, calculated by weight percentage, comprising the following raw materials: 40% epoxy resin, 16% polyacrylate, 2% hexamethylene diisocyanate, 7% diaminodiphenylmethane, 25% modified carbon fiber, and 10% ultra-high molecular weight polyethylene fiber;

[0092] The preparation method of the high-strength fiber composite material in Comparative Example 7 is the same as that in Example 2, and the raw materials are weighed according to the weight percentages in Comparative Example 7.

[0093] Comparative Example 8

[0094] A high-strength fiber composite material, calculated by weight percentage, comprising the following raw materials: 50% epoxy resin, 9% polyacrylate, 2.5% hexamethylene diisocyanate, 5% diaminodiphenylmethane, 26% modified carbon fiber, and 7.5% ultra-high molecular weight polyethylene fiber;

[0095] The preparation method of the high-strength fiber composite material in Comparative Example 8 is the same as that in Example 4, and the raw materials are weighed according to the weight percentages in Comparative Example 8.

[0096] Comparative Example 9

[0097] A high-strength fiber composite material, calculated by weight percentage, comprising the following raw materials: 50% epoxy resin, 10% polyacrylate, 3.5% hexamethylene diisocyanate, 5% diaminodiphenylmethane, 24% modified carbon fiber, and 7.5% ultra-high molecular weight polyethylene fiber;

[0098] The preparation method of the high-strength fiber composite material in Comparative Example 9 is the same as that in Example 4, and the raw materials are weighed according to the weight percentages in Comparative Example 9.

[0099] Comparative Example 10

[0100] A high-strength fiber composite material, calculated by weight percentage, comprising the following raw materials: 50% epoxy resin, 10% polyacrylate, 0.5% hexamethylene diisocyanate, 7% diaminodiphenylmethane, 25% modified carbon fiber, and 7.5% ultra-high molecular weight polyethylene fiber;

[0101] The preparation method of the high-strength fiber composite material of Comparative Example 10 is the same as that of Example 4, and the raw materials are weighed according to the weight percentages in Comparative Example 10.

[0102] The high-strength fiber composite materials prepared in Examples 1 to 7 and Comparative Examples 1 to 10 were tested, and the performance results are shown in Table 1.

[0103] Mechanical properties test: Use a universal material testing machine to perform tensile and bending tests on the fibers at the test temperature and humidity required by the mechanical properties test standards, and calculate the elastic modulus and elongation at break of the material.

[0104] Wear resistance test: Use a simulated friction tester with a load of 500g and a test period of 1500 times in a bidirectional scraping mode. Record the sample weight at the end of the test and calculate the wear loss and friction coefficient.

[0105] Table 1 Performance

[0106]

[0107] As can be seen from Table 1, Examples 1 to 7 of the present invention select epoxy resin, polyacrylate, isocyanate crosslinking agent, curing agent, modified carbon fiber and ultra-high molecular weight polyethylene fiber to cooperate with each other, take into account the compatibility and interface bonding ability of the raw materials, promote the resin composite material to have a stronger structure, and design a suitable raw material ratio to take into account the rigidity and toughness of the resin fiber composite material, improve the strength of the resin fiber composite material, improve the overall performance of the resin fiber composite material, make the resin fiber composite material prepared product have high toughness and impact resistance, and extend the service life of the resin fiber composite material.

[0108] Combining Example 1 and Comparative Example 1, Comparative Example 2, and Comparative Example 3, it can be seen that the carbon fiber is oxidized to a surface containing a carboxyl group and grafted with a vinyl silane coupling agent, so that the surface activity of the carbon fiber can better promote the improvement of the compatibility between the fiber and the resin, and greatly enhance the interfacial bonding strength between the fiber and the resin. Moreover, under the action of the crosslinking agent and the curing agent, the modified carbon fiber containing the carboxyl gene and the epoxy resin can form a certain network structure, which is beneficial for the composite material to take into account both rigidity and toughness, so that the composite material has higher stability and improves the overall performance of the resin fiber material.

[0109] In combination with Example 4 and Comparative Examples 3, 4, 8 and 9, it can be seen that by blending polyacrylate with epoxy resin, during curing, the polyacrylate resin can reduce the internal stress of the epoxy resin, improve the toughness of the epoxy resin, and solve the problem of brittleness of the epoxy resin due to its high cross-linking density. In addition, by adding a suitable cross-linking agent, a chemical bond can be formed between the polyacrylate and the epoxy resin, so that the two form a tighter cross-linked network structure, and at the same time, the interfacial bonding strength between the epoxy resin and the fiber is enhanced, thereby improving the structural stability of the resin composite material and improving the overall performance of the resin composite material such as rigidity, toughness and wear resistance. In addition, in combination with Example 4 and Comparative Examples 6 and 7, an appropriate amount of polyacrylate added is more helpful for the resin fiber composite material to have both rigidity and toughness. Excessive addition of polyacrylate will lead to a decrease in rigidity, and excessive addition of polyacrylate will lead to a decrease in toughness.

[0110] From Example 1 and Comparative Example 5, it can be seen that the addition of ultra-high molecular weight polyethylene fibers can further improve the wettability between the fibers and the resin matrix, and also enhance the interfacial bonding ability between the fibers and the resin matrix, thereby enhancing the rigidity and toughness of the resin composite material while enhancing the wear resistance of the resin composite material, thereby significantly improving the impact resistance and toughness of the composite material and extending its service life.

[0111] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be embodied in other specific forms without departing from the spirit and essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations that come within the meaning and range of equivalents of the claims be embraced therein.

[0112] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A high-strength fiber composite material, characterized in that: Calculated by weight percentage, it includes the following raw materials: epoxy resin 40-50%, polyacrylate 10-15%, isocyanate crosslinking agent 2-3%, curing agent 5-9%, modified carbon fiber 23-30%, ultra-high molecular weight polyethylene fiber 6-12%; The modified carbon fiber is selected from carbon fibers that are oxidized to form a surface containing carboxyl groups, and then grafted with a vinyl-containing silane coupling agent; The preparation process of modified carbon fiber is as follows: (1) Add carbon fiber to concentrated sulfuric acid, ultrasonically treat, and then perform surface oxidation treatment. Then filter and wash with water until neutral, and vacuum dry to obtain carbon fiber containing carboxyl groups. (2) The carbon fiber containing carboxyl groups is soaked in acetone, and then a vinyl silane coupling agent is added, ultrasonically treated, and then grafted. The carbon fiber is filtered and washed with acetone, and vacuum dried to obtain a modified carbon fiber. The method for preparing the high-strength fiber composite material comprises the following steps: S1. According to the weight percentage of the raw materials, the epoxy resin and the polyacrylate are stirred and mixed to obtain a resin solution; S2. Immersing the modified carbon fiber and the ultra-high molecular weight polyethylene fiber in the resin mixture according to the weight percentage of the raw materials, and stirring and mixing them uniformly to obtain a resin mixture; S3, adding an isocyanate crosslinking agent and a curing agent to the resin mixture according to the weight percentage of the raw materials, stirring and mixing them uniformly, and degassing to obtain a blended spinning solution; S4. The blended spinning solution is subjected to electrostatic spinning and then thermally cross-linked to obtain a high-strength fiber composite material.

2. A high-strength fiber composite material according to claim 1, characterized in that: The vinyl-containing silane coupling agent is one of vinyltrimethoxysilane, vinyltriethoxysilane or methylvinyldiethoxysilane.

3. The high-strength fiber composite material according to claim 1, characterized in that: The ratio of the carbon fiber mass to the concentrated sulfuric acid volume is 1g:(100-110)ml; the ratio of the carbon fiber mass to the volume of the vinyl-containing silane coupling agent and the volume of acetone is 1g:0.4ml:(40-50)ml.

4. The high-strength fiber composite material according to claim 1, characterized in that: The isocyanate cross-linking agent is one of hexamethylene diisocyanate, toluene diisocyanate or dicyclohexylmethane-4,4'-diisocyanate.

5. The high-strength fiber composite material according to claim 1, characterized in that: The curing agent is one of diaminodiphenylmethane and 4,4'-diaminodicyclohexylmethane.

6. The high-strength fiber composite material according to any one of claims 1 to 5, characterized in that: Calculated by weight percentage, it includes the following raw materials: epoxy resin 44%, polyacrylate 12%, isocyanate cross-linking agent 2.5%, curing agent 7.5%, modified carbon fiber 26%, and ultra-high molecular weight polyethylene fiber 8%.

7. The high-strength fiber composite material according to claim 1, characterized in that: The temperature of the thermal crosslinking treatment is 110-120° C., and the time is 2-3 hours.

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