阅读说明：本技术 一种稀土改性碳纳米管/碳纤维多尺度增强体及其制备方法和应用 (Rare earth modified carbon nanotube/carbon fiber multi-scale reinforcement and preparation method and application thereof ) 是由 程先华 汤皓 李玮 于 2021-10-28 设计创作，主要内容包括：本发明涉及一种稀土改性碳纳米管/碳纤维多尺度增强体及其制备方法和应用,该增强体包括以下重量份组分：5-50份经稀土改性的碳纳米管和2000份经稀土改性的碳纤维,其制备方法包括以下步骤：碳纤维的稀土处理；碳纳米管的稀土处理；将经稀土改性的碳纤维均匀分散于平板上；将经稀土改性的碳纳米管分散液逐滴滴加在经稀土改性的碳纤维表面；滴加完成后进行加热,再洗涤并过滤,得到稀土改性碳纳米管/碳纤维多尺度增强体,该增强体用于与树脂复合制备复合材料。与现有技术相比,本发明具有表面活性大、与树脂基体粘结性好、拉伸强度高等优点。(The invention relates to a rare earth modified carbon nanotube/carbon fiber multi-scale reinforcement and a preparation method and application thereof, wherein the reinforcement comprises the following components in parts by weight: 5-50 parts of rare earth modified carbon nano tube and 2000 parts of rare earth modified carbon fiber, wherein the preparation method comprises the following steps: rare earth treatment of carbon fibers; rare earth treatment of the carbon nano tube; uniformly dispersing the rare earth modified carbon fiber on a flat plate; dropwise adding the rare earth modified carbon nanotube dispersion liquid on the surface of the rare earth modified carbon fiber; and after the dropwise addition is finished, heating, washing and filtering to obtain the rare earth modified carbon nanotube/carbon fiber multi-scale reinforcement, wherein the reinforcement is used for preparing the composite material by compounding with resin. Compared with the prior art, the invention has the advantages of large surface activity, good cohesiveness with resin matrix, high tensile strength and the like.)

1. The rare earth modified carbon nanotube/carbon fiber multi-scale reinforcement is characterized by comprising the following components in parts by weight: 5-50 parts of carbon nano tube modified by rare earth and 2000 parts of carbon fiber modified by rare earth.

2. The rare earth-modified carbon nanotube/carbon fiber multi-scale reinforcement of claim 1, wherein the end face of the rare earth-modified carbon nanotube is enriched with active groups, and the end face of the carbon nanotube selectively connects with the surface of the rare earth-modified carbon fiber through chemical bonds.

3. A method for preparing a rare earth modified carbon nanotube/carbon fiber multi-scale reinforcement according to claim 1 or 2, comprising the steps of:

rare earth treatment of carbon fibers: putting carbon fiber into LaCl₃-stirring, standing and filtering the alcohol solution, and heating the filtered substance to obtain rare earth modified carbon fiber;

rare earth treatment of carbon nanotubes: placing carbon nanotubes into LaCl₃-adding urea into an alcoholic solution after ultrasonic dispersion and stirring, then performing ultrasonic dispersion, standing, then filtering, heating a filtered substance, and then grinding into powder to obtain a rare earth modified carbon nanotube;

uniformly dispersing the rare earth modified carbon fiber on a flat plate;

ultrasonically dispersing the carbon nano tube modified by the rare earth into a dispersing agent to obtain a rare earth modified carbon nano tube dispersion liquid;

dropwise adding the rare earth modified carbon nanotube dispersion liquid on the surface of the rare earth modified carbon fiber;

and after the dripping is finished, heating, washing and filtering to obtain the rare earth modified carbon nano tube/carbon fiber multi-scale reinforcement.

4. The method for preparing a multi-scale reinforcement of rare earth modified carbon nanotube/carbon fiber according to claim 3, wherein the carbon fiber is mixed with LaCl₃The mass-to-volume ratio of the alcoholic solution is (1.5-3.5) g (40-80) mL; the carbon nano tube and the LaCl₃The mass-to-volume ratio of the alcohol solution (50-250) mg (75-150) mL; the LaCl₃-LaCl in alcoholic solution₃The concentration is 0.010-0.100 mmol/L.

5. The method for preparing the rare earth modified carbon nanotube/carbon fiber multi-scale reinforcement according to claim 3, wherein the mass ratio of urea to carbon nanotubes is (1.5-3.0) g (50-250) mg.

6. The method for preparing the rare earth modified carbon nanotube/carbon fiber multi-scale reinforcement according to claim 3, wherein the stirring time is 8-16h, the ultrasonic dispersion time is 20-40min, the standing time is 8-16h, the heating temperature is 95-105 ℃ and the heating time is 5-8 h.

7. The method for preparing rare earth modified carbon nanotube/carbon fiber multi-scale reinforcement according to claim 3, wherein the carbon fiber is powder with a particle size of 200 meshes, the length of 20-70 μm and the diameter of 6-7 μm.

8. The method for preparing the rare earth modified carbon nanotube/carbon fiber multi-scale reinforcement according to claim 3, wherein the specific operations of dispersing on the flat plate are as follows: adding 0.25-1.25g of carbon fiber into 6-10mL of ethanol, performing ultrasonic treatment for 10-30s, and directly pouring onto a glass plate until the ethanol is automatically evaporated.

9. The method for preparing the rare earth modified carbon nanotube/carbon fiber multi-scale reinforcement according to claim 3, wherein the specific operation of dropwise adding is as follows: and sucking the dispersion liquid by using a syringe, and dropwise adding the dispersion liquid on the surface of the carbon fiber, wherein the diameter of a syringe needle hole is 450-600 mu m, and the volume of one drop of the dispersion liquid is 10-14 mu L.

10. Use of the rare earth-modified carbon nanotube/carbon fiber multi-scale reinforcement according to claim 1 or 2 for preparing a composite material by compounding the reinforcement with a resin.

Technical Field

The invention relates to the field of composite materials, in particular to a rare earth modified carbon nanotube/carbon fiber multi-scale reinforcement and a preparation method and application thereof.

Background

The carbon fiber reinforced resin matrix composite material has the characteristics of light weight, high strength, good fatigue resistance, strong designability, structural function integration and the like, and is a novel base material with great development potential. However, the carbon fiber surface is chemically inert and has poor wettability with the resin matrix, so that the carbon fiber surface needs to be modified to improve the performance of the composite material. In many researches on the surface modification of carbon fibers, the carbon nanotubes are introduced to the surface of the carbon fibers to construct a micro-nano multi-scale reinforcement, so that the excellent performances of the carbon fibers and the carbon nanotubes can be fully exerted, and therefore, the research interest is widely aroused.

The carbon nano tube/carbon fiber multi-scale reinforcement is a novel reinforcement which is formed by grafting carbon nano tubes on the surface of carbon fibers and fully reinforcing a composite material through the synergistic effect of the nano-scale carbon nano tubes and the micron-scale carbon fibers. The carbon nano tube/carbon fiber multi-scale reinforcement and the resin matrix form an interface layer with novel structural characteristics, so that the contact area of the reinforcement and the matrix is increased, the mechanical meshing effect of the interface is improved, the respective excellent characteristics of the carbon nano tube and the carbon fiber are exerted, the chemical bonding effect of the respective surface and the matrix is promoted, the bonding performance between the composite reinforcement and the resin matrix can be obviously improved, and the high-performance resin matrix composite material is prepared.

At present, the preparation method of the carbon nano tube/carbon fiber multi-scale reinforcement mainly comprises a chemical vapor deposition method, an electrophoretic deposition method, an electrospray deposition method and a functional group grafting method. In contrast to the relatively complex, high energy consumption and expensive equipment required in the chemical vapor deposition, electrophoretic deposition and electrospray deposition processes, the functional group grafting process is relatively simple and low in cost, and is gradually the focus of current research. Generally, the functional group grafting method firstly adopts strong acid or strong oxidant treatment to respectively functionalize the carbon fibers on the surfaces of the carbon nanotubes, and then completes the grafting reaction of the carbon nanotubes and the carbon fibers in a specific medium. However, the strong acid or strong oxidant treatment adopted in the functional group grafting method damages the surface structures of the carbon nanotubes and the carbon fibers, and the remaining acid solution/oxidant and the reaction solution of the grafting reaction also leave high-concentration harmful wastes in the process.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provide a rare earth modified carbon nanotube/carbon fiber multi-scale reinforcement with large surface activity, good adhesion with a resin matrix and high tensile strength, and a preparation method and application thereof.

The purpose of the invention can be realized by the following technical scheme:

a rare earth modified carbon nanotube/carbon fiber multi-scale reinforcement comprises the following components in parts by weight: 5-50 parts of carbon nano tube modified by rare earth and 2000 parts of carbon fiber modified by rare earth.

Furthermore, the end face of the carbon nano tube modified by the rare earth is enriched with active groups, and the end face of the carbon nano tube is selectively connected with the surface of the carbon fiber modified by the rare earth through chemical bonds.

A preparation method of the rare earth modified carbon nanotube/carbon fiber multi-scale reinforcement comprises the following steps:

rare earth treatment of carbon fibers: putting carbon fiber into LaCl₃-stirring, standing and filtering the alcohol solution, and heating the filtered substance to obtain rare earth modified carbon fiber;

rare earth treatment of carbon nanotubes: placing carbon nanotubes into LaCl₃-adding urea into an alcoholic solution after ultrasonic dispersion and stirring, then performing ultrasonic dispersion, standing, then filtering, heating a filtered substance, and then grinding into powder to obtain a rare earth modified carbon nanotube;

uniformly dispersing the rare earth modified carbon fiber on a flat plate;

ultrasonically dispersing the carbon nano tube modified by the rare earth into a dispersing agent to obtain a rare earth modified carbon nano tube dispersion liquid;

dropwise adding the rare earth modified carbon nanotube dispersion liquid on the surface of the rare earth modified carbon fiber;

and after the dripping is finished, heating, washing and filtering to obtain the rare earth modified carbon nano tube/carbon fiber multi-scale reinforcement.

The carbon fiber surface has relatively more nitrogen-oxygen active groups generated in the preparation process, and the carbon fiber is placed in rare earth LaCl₃Fully soaking in ethanol solution to facilitate La³⁺Coordination reaction with active atom (nitrogen in amino group, hydroxyl group in carboxyl group, etc.), and La³⁺Adsorbing on the surface of the carbon fiber.

The ultrasonic treatment can promote the opening of the carbon nano tube port and the breakage of the surface defect while dispersing the carbon nano tube uniformly, so that the active groups are enriched on the end face of the newly generated carbon nano tube. After ultrasonic treatment, fully soaking the carbon nano tube in a rare earth alcohol solution, and La³⁺Can be adsorbed on the surface of the carbon nanotube by coordinating with nitrogen and oxygen atoms on the surface, besides, La³⁺Can also be prepared by ion exchange reaction of 3R-OH + LaCl₃→(R-0)₃The La +3HCl and the hydroxyl on the surface of the carbon nano tube generate chemical bond connection. After standing still, La is fully adsorbed on the end face of the carbon nano tube³⁺At this time, by adding urea to the solution, La is allowed to be present³⁺Through the coordination reaction with active nitrogen and oxygen atoms in urea molecules, passing the urea molecules through La³⁺Adsorbed on the surface of the carbon nano tube.

Obtaining the end face functionalized carbon nano tube and adsorbing La on the surface³⁺After the carbon fiber is prepared, the CNT is uniformly distributed in the ethanol solution by ultrasonic dispersion, and then the liquid phase is directly dipped on the surface of the CF in the state, so that the condition that CF powder is deposited at the bottom of the solution and can not fully contact the CNT when the CF and the CNT are directly mixed is avoided. Since the carbon nanotubes are mainly functionalized by urea molecules at the end faces, La adsorbed on the surface of the carbon fibers³⁺Mainly has coordination reaction with active nitrogen and oxygen atoms on the end face of the carbon nano tube, and the carbon nano tube selectively grafts the end face on the surface of the carbon fiber to form a 'tree root-shaped' reinforcement. Similarly, the exposed hydroxyl on the surfaces of the carbon nanotube and the carbon fiber and the La on the surfaces of the carbon nanotube and the carbon fiber³⁺Chemical bonds are created by ion exchange reactions.

Further, the carbon fiber and LaCl₃The mass-to-volume ratio of the alcoholic solution is (1.5-3.5) g (40-80) mL; the carbon nano tube and the LaCl₃The mass-to-volume ratio of the alcohol solution (50-250) mg (75-150) mL; the LaCl₃-LaCl in alcoholic solution₃The concentration is 0.010-0.100 mmol/L.

Furthermore, the mass ratio of the urea to the carbon nano tubes is (1.5-3.0) g, (50-250) mg.

Further, the stirring time is 8-16h, the ultrasonic dispersion time is 20-40min, the standing time is 8-16h, the heating temperature is 95-105 ℃, and the heating time is 5-8 h.

Further, the carbon fiber is powder with the granularity of 200 meshes, the length of 20-70 mu m and the diameter of 6-7 mu m. Prepared by desizing Dongli T700-12k series carbon fibers.

Further, the specific operations dispersed on the plate are: adding 0.25-1.25g of carbon fiber into 6-10mL of ethanol, performing ultrasonic treatment for 10-30s, and directly pouring onto a glass plate until the ethanol is automatically evaporated.

Further, the specific operation of dropwise adding is as follows: and sucking the dispersion liquid by using a syringe, and dropwise adding the dispersion liquid on the surface of the carbon fiber, wherein the diameter of a syringe needle hole is 450-600 mu m, and the volume of one drop of the dispersion liquid is 10-14 mu L.

An application of rare earth modified carbon nanotube/carbon fiber multi-scale reinforcement is disclosed, wherein the reinforcement is used for preparing a composite material by compounding with resin.

Compared with the prior art, the invention has the following advantages:

(1) the rare earth surface modification technology adopted by the invention enables the end face of the carbon nano tube to be selectively grafted on the surface of the carbon fiber, so that the rare earth modified carbon nano tube/carbon fiber multi-scale reinforcement with large surface activity and good wettability with a resin matrix is prepared, and the tensile strength of the epoxy resin matrix composite material can be improved by about 40%;

(2) the preparation process of the rare earth modified carbon nanotube/carbon fiber multi-scale reinforcement has the advantages of low cost, simple process and no high-concentration harmful waste, improves the mechanical property of the composite material, and promotes the popularization and the use of the carbon nanotube/carbon fiber multi-scale reinforcement composite material in various fields.

Drawings

FIG. 1 is a schematic structural diagram of a rare earth-modified carbon nanotube/carbon fiber multi-scale reinforcement;

FIG. 2 is an electron microscope picture of the multi-scale reinforcement of rare earth-modified carbon nanotube/carbon fiber prepared in example 1;

FIG. 3 is a schematic diagram showing the agglomeration of carbon nanotubes in a dispersion liquid when the dipping time is relatively long;

in the figure, 1 is a carbon nanotube modified by rare earth, and 2 is a carbon fiber modified by rare earth.

Detailed Description

The invention is described in detail below with reference to the figures and specific embodiments. The present embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation manner and a specific operation process are given, but the protection scope of the present invention is not limited to the following embodiments.

A preparation method of rare earth modified carbon nanotube/carbon fiber multi-scale reinforcement comprises the following steps:

rare earth treatment of carbon fibers: putting carbon fiber into LaCl₃Alcoholic solutions (e.g. LaCl)₃-ethanol solution), stirring, standing, filtering, and heating the filtered substance to obtain rare earth modified carbon fiber; carbon fiber and LaCl₃The mass-to-volume ratio of the alcoholic solution is (1.5-3.5) g (40-80) mL; LaCl₃-LaCl in alcoholic solution₃The concentration is 0.010-0.100 mmol/L; the carbon fiber is powder with the granularity of 200 meshes, the length of 20-70 μm and the diameter of 6-7 μm. Is prepared by desizing Dongli T700-12k series carbon fiber; stirring for 8-16h, standing for 8-16h, heating at 95-105 deg.C for 5-8 h.

Rare earth treatment of carbon nanotubes: placing carbon nanotubes into LaCl₃-adding urea into an alcoholic solution after ultrasonic dispersion and stirring, then performing ultrasonic dispersion, standing, then filtering, heating a filtered substance, and then grinding into powder to obtain a rare earth modified carbon nanotube; carbon nanotubeWith LaCl₃The mass-to-volume ratio of the alcohol solution (50-250) mg (75-150) mL; LaCl₃-LaCl in alcoholic solution₃The concentration is 0.010-0.100mmol/L, the mass ratio of urea to the carbon nano tube is (1.5-3.0) g, (50-250) mg; stirring for 8-16h, ultrasonic dispersing for 20-40min, standing for 8-16h, heating at 95-105 deg.C for 5-8 h;

uniformly dispersing the rare earth modified carbon fiber on a flat plate (such as a glass flat plate with the thickness of 200mm multiplied by 300 mm); the specific operation is as follows: adding 0.25-1.25g of carbon fiber into 6-10mL of ethanol, performing ultrasonic treatment for 10-30s, and directly pouring onto a glass plate until the ethanol is automatically evaporated;

ultrasonically dispersing the carbon nano tube modified by the rare earth into a dispersing agent (such as ethanol) to obtain a rare earth modified carbon nano tube dispersion liquid; dropwise adding the rare earth modified carbon nanotube dispersion liquid on the surface of the rare earth modified carbon fiber; the specific operation is as follows: absorbing the dispersion liquid by using an injector, and dropwise adding the dispersion liquid on the surface of the carbon fiber, wherein the diameter of a pinhole of the injector is 450-600 mu m, and the volume of one drop of the dispersion liquid is 10-14 mu L;

heating after the dripping is finished, washing and filtering to obtain the rare earth modified carbon nano tube/carbon fiber multi-scale reinforcement, as shown in figure 1. Heating at 95-105 deg.C for 5-8 h;

the reinforcement comprises the following components in parts by weight: 5-50 parts of carbon nano tube modified by rare earth and 2000 parts of carbon fiber modified by rare earth. The end face of the carbon nano tube modified by the rare earth is enriched with active groups, the end face of the carbon nano tube is selectively connected with the surface of the carbon fiber modified by the rare earth to generate chemical bonds, and the reinforcement is used for compounding with resin to prepare the composite material.

Example 1

A preparation method of rare earth modified carbon nanotube/carbon fiber multi-scale reinforcement comprises the following steps:

(1) rare earth treatment of carbon fibers: putting carbon fiber into LaCl₃Stirring in an ethanol solution for 12h, standing for 12h, filtering, and heating the filtered substance at 100 ℃ for 6h to obtain rare earth modified carbon fibers; wherein, the carbon fiber and the LaCl₃-BThe mass-volume ratio of the alcoholic solution is (3.0-3.2) g:50 mL; LaCl₃-LaCl in ethanol solution₃The concentration is 0.015-0.016 mmol/L; the carbon fiber is powder with the granularity of 200 meshes, the length of 20-70 μm and the diameter of 6-7 μm. Is prepared by desizing Dongli T700-12k series carbon fiber;

(2) rare earth treatment of carbon nanotubes: placing carbon nanotubes into LaCl₃Ultrasonically dispersing for 30min in an alcohol solution, stirring for 12h, adding urea, ultrasonically dispersing for 30min, standing for 12h, filtering, heating the filtered substance at 100 ℃ for 6h, and grinding into powder to obtain the rare earth modified carbon nanotube; wherein, the carbon nano tube and the LaCl₃-mass to volume ratio of alcoholic solution (40-50) mg:50 mL; LaCl₃-LaCl in alcoholic solution₃The concentration is 0.015-0.016mmol/L, the mass ratio of urea to carbon nano tube is (2.0-2.2) g:50 mg;

(3) uniformly dispersing the rare earth modified carbon fiber on a flat plate (such as a glass flat plate with the thickness of 200mm multiplied by 300 mm); the specific operation is as follows: adding 0.25-1.25g of carbon fiber into 6-10mL of ethanol, performing ultrasonic treatment for 10-30s, and directly pouring onto a glass plate until the ethanol is automatically evaporated; simultaneously, ultrasonically dispersing the carbon nano tube modified by the rare earth into a dispersing agent ethanol to obtain a rare earth modified carbon nano tube dispersion liquid;

(4) dropwise adding the rare earth modified carbon nanotube dispersion liquid on the surface of the rare earth modified carbon fiber; the specific operation is as follows: absorbing the dispersion liquid by using an injector, and dropwise adding the dispersion liquid on the surface of the carbon fiber, wherein the diameter of a pinhole of the injector is 450-600 mu m, and the volume of one drop of the dispersion liquid is 10-14 mu L;

(5) after the dropwise addition is finished, heating is carried out for 6 hours at the temperature of 100 ℃, washing and filtering are carried out, so as to obtain the rare earth modified carbon nanotube/carbon fiber multi-scale reinforcement, as shown in figure 2, the reinforcement comprises the following components in parts by weight: 40-50 parts of rare earth modified carbon nano tube and 2000 parts of rare earth modified carbon fiber. The end face of the carbon nano tube modified by the rare earth is enriched with active groups, and the end face of the carbon nano tube is selectively connected with the surface of the carbon fiber modified by the rare earth to generate chemical bonds.

The reinforcement is used for preparing a composite material by compounding with resin, benzene-free environment-friendly epoxy resin with the tensile strength of 30MPa is used as a matrix, the filling mass proportion of the reinforcement is controlled to be 5.0%, and the resin/fiber composite material is obtained, wherein the tensile strength is about 54 MPa.

In the embodiment, the dropping method is adopted, because the liquid phase contained in the liquid drop is less, after the liquid drop is dropped on the surface of the carbon fiber, the liquid drop quickly spreads on the surface of the carbon fiber, and simultaneously the alcohol solvent quickly evaporates, so that agglomeration of the carbon nanotubes is avoided, and if the dipping treatment is adopted, the carbon nanotubes are easily agglomerated in the dispersion liquid due to the relatively long dipping time (at least over 5 minutes), as shown in fig. 3.

Comparative example 1

The difference from the embodiment 1 is that the tensile strength of the composite material obtained by replacing the rare earth modified carbon nanotube/carbon fiber multi-scale reinforcement with the same mass part of carbon fiber is about 37 MPa.

Comparative example 2

The difference from the embodiment 1 is that the tensile strength of the composite material prepared by replacing the rare earth modified carbon nanotube/carbon fiber multi-scale reinforcement with the same mass part of carbon fiber and treating the carbon fiber by liquid phase oxidation is about 40 MPa. The specific preparation method refers to Zhang Zhongwei, Tan Kogyo, Tuqiang, and the like, and the mechanical property [ J ] of the ball milling-liquid phase oxidation short carbon fiber reinforced epoxy resin composite material, war academic newspaper 2013,34(7): 869-.

Comparative example 3

The difference from the embodiment 1 is that the carbon fiber modified by the rare earth is replaced by the carbon fiber with the same mass part, the carbon nanotube modified by the rare earth is replaced by the carbon nanotube with the same mass part, and the tensile strength of the composite material prepared by adopting the strong acid oxidation method is 39-47 MPa.

The strong acid oxidation method comprises the following specific steps:

(1) preparation H₂SO₄/HNO₃(v: v ═ 3:1) by adding the carbon fiber to the solution, heating at 60 ℃ for reaction for 2 hours, then filtering, washing several times with absolute ethyl alcohol, and finally drying in an oven at 60 ℃ for 12 hours to obtain the strong acid oxidized carbon fiber.

(2) Uniformly dispersing the carbon fiber oxidized by the strong acid on a flat plate (such as a glass flat plate of 200mm multiplied by 300 mm); the specific operation is as follows: adding 0.25-1.25g of carbon fiber into 6-10mL of ethanol, performing ultrasonic treatment for 10-30s, and directly pouring onto a glass plate until the ethanol is automatically evaporated; simultaneously, ultrasonically dispersing the carboxylated carbon nano tube (Nanjing Xiancheng nano tube) in a dispersing agent ethanol to obtain a carbon nano tube dispersion liquid;

(3) dropwise adding the carbon nanotube dispersion liquid on the surface of the carbon fiber oxidized by strong acid; the specific operation is as follows: absorbing the dispersion liquid by using an injector, and dropwise adding the dispersion liquid on the surface of the carbon fiber, wherein the diameter of a pinhole of the injector is 450-600 mu m, and the volume of one drop of the dispersion liquid is 10-14 mu L;

(4) after the dropwise addition is finished, heating for 6h at 100 ℃, washing and filtering to obtain the strong acid oxidized carbon nanotube/carbon fiber multi-scale reinforcement, wherein the reinforcement comprises the following components in parts by weight: 40-50 parts of rare earth modified carbon nano tube and 2000 parts of strong acid oxidized carbon fiber.

(5) The reinforcement is used for preparing a composite material by compounding with resin, benzene-free environment-friendly epoxy resin with the tensile strength of 30MPa is used as a matrix, the filling mass proportion of the reinforcement is controlled to be 5.0 percent, and the resin/fiber composite material is obtained, wherein the tensile strength is 39-47 MPa.

Therefore, the tensile strength of the rare earth modified carbon nanotube/carbon fiber multi-scale reinforced epoxy resin prepared in the embodiment 1 is 80% higher than that of a pure epoxy resin, and compared with the tensile strength improved by 15% in the existing typical process, the tensile strength is obviously improved.

The foregoing is directed to preferred embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow. However, any simple modification, equivalent change and modification of the above embodiments according to the technical essence of the present invention are within the protection scope of the technical solution of the present invention.