CN115467164A - Modified fiber and preparation method thereof, reinforced thermoplastic composite material and application thereof - Google Patents

Abstract

The application provides a modified fiber and a preparation method thereof, a reinforced thermoplastic composite material and application thereof, relating to the field of materials. A method of making a modified fiber comprising: carrying out first mixing on a first glacial acetic acid aqueous solution and an amino coupling agent, then adding nanoparticles for first reaction, and then carrying out first solid-liquid separation and first drying to obtain modified nanoparticles; and carrying out second mixing on a second glacial acetic acid aqueous solution and an epoxy coupling agent, then adding the fiber for second reaction, adding the modified nano particles and the film-forming emulsion after the second reaction is finished, and carrying out second solid-liquid separation and second drying after the reaction is continued to obtain the modified fiber. The preparation method provided by the application can greatly improve the surface activity and the roughness of the fiber, improve the infiltration capacity and the interface bonding strength of the thermoplastic resin to the fiber, and realize high-performance production and application of the fiber reinforced thermoplastic composite material.

Description

Modified fiber and its preparation method, reinforced thermoplastic composite material and its use

technical field

The application relates to the field of materials, in particular to a modified fiber and a preparation method thereof, a reinforced thermoplastic composite material and applications thereof.

Background technique

Fiber-reinforced thermoplastic resin composite materials have the characteristics of environmental protection, light weight, high strength, rust and weather resistance, etc. Fiber-reinforced thermoplastic composite materials represented by carbon fiber, basalt fiber, aramid fiber, glass fiber, etc. It has important application value in fields such as rail transit, automobiles and ships, and new energy infrastructure.

At present, the surface organic matter of conventional fibers is mostly suitable for thermosetting resin systems, such as epoxy resin, unsaturated resin, etc., but in thermoplastic composite materials, the surface functional groups are difficult to combine with thermoplastic resin systems, and there are molecular structures. It is difficult to prepare high-performance fiber-reinforced thermoplastic composites, which seriously hinders the high-end application of carbon fiber, basalt fiber, aramid fiber, glass fiber and their composite materials.

Contents of the invention

The purpose of this application is to provide a modified fiber and its preparation method, a reinforced thermoplastic composite material and its use, so as to solve the above problems.

To achieve the above object, the application adopts the following technical solutions:

A preparation method of modified fiber, comprising:

Mixing the first aqueous solution of glacial acetic acid and the amino coupling agent for the first time, then adding nanoparticles to carry out the first reaction, then performing the first solid-liquid separation, and the first drying to obtain modified nanoparticles;

The second glacial acetic acid aqueous solution and the epoxy-based coupling agent are mixed for the second time, and then the fiber is added for the second reaction. After the second reaction is completed, the modified nanoparticles and the film-forming emulsion are added, and the reaction is continued. second solid-liquid separation and second drying to obtain the modified fiber;

The fibers include one or more of basalt fibers, carbon fibers, glass fibers, and aramid fibers, and the nanoparticles include nano silicon dioxide and/or nano titanium dioxide.

Preferably, the mass fractions of the first aqueous glacial acetic acid solution and the second aqueous glacial acetic acid solution are independently 0.03%-0.2%.

Preferably, the preparation method meets at least one of the following conditions:

a. the amino coupling agent comprises a single amino coupling agent and/or a polyamino coupling agent;

b. the consumption of the amino coupling agent is 0.2%-4.0% of the consumption of the water in the first glacial acetic acid aqueous solution;

c. The time for the first mixing is 0.5h-2h.

Preferably, the preparation method meets at least one of the following conditions:

d. The amount of the nanoparticles is 0.5%-10% of the amount of water in the first aqueous solution of glacial acetic acid;

e. The first reaction is carried out under stirring conditions, the reaction temperature is 50°C-95°C, and the stirring time is 3h-6h.

Preferably, the preparation method meets at least one of the following conditions:

f. the epoxy-based coupling agent includes a single epoxy-based coupling agent and/or multiple epoxy-based coupling agents;

g. the consumption of the epoxy group coupling agent is 0.2%-4% of the consumption of the water in the second glacial acetic acid aqueous solution;

h. The time for the second mixing is 2h-6h.

Preferably, the preparation method meets at least one of the following conditions:

i. the consumption of the fiber is 5%-20% of the consumption of the water in the second glacial acetic acid aqueous solution;

j. The second reaction is carried out under the assistance of ultrasonic waves, the reaction temperature is 50°C-95°C, and the reaction time is 2h-4h;

k. The amount of the modified nanoparticles is 0.5%-2.5% of the amount of water in the second glacial acetic acid aqueous solution.

Preferably, the preparation method meets at least one of the following conditions:

l. described film-forming emulsion comprises one or more in epoxy emulsion, polyester emulsion and acrylic acid emulsion;

m. the consumption of the film-forming emulsion is 1%-5% of the consumption of the water in the second glacial acetic acid aqueous solution;

n. The time for continuing the reaction is 1h-3h.

The present application also provides a modified fiber, which is prepared by the method for preparing the modified fiber.

The present application also provides a reinforced thermoplastic composite material, including the modified fiber.

The present application also provides a use of reinforced thermoplastic composite materials, which are used in the fields of aerospace, national defense and military industry, rail transportation, automobiles and ships, and new energy infrastructure.

Compared with the prior art, the beneficial effects of the present application include:

The preparation method of the modified fiber provided by this application can greatly improve the surface activity and roughness of fibers such as basalt fiber, carbon fiber, glass fiber, and aramid fiber, and improve the wetting ability and interface bonding strength of thermoplastic resin to fibers. It can realize the high-performance production and application of fiber-reinforced thermoplastic composite materials such as basalt fiber, carbon fiber, glass fiber, and aramid fiber.

Specifically, the nanoparticles are firstly modified, and the surface is coated with an organic compound containing an amino group to improve its surface reactivity and particle dispersion; then the fiber material is modified, and an organic compound containing an epoxy group is coated on its surface. , to improve its surface reactivity and interfacial compatibility; finally, the modified nanoparticles and emulsion are introduced into the system, and modified with the fiber material treated by the coupling agent to obtain the modified fiber. Since the amino group on the surface of the nanoparticle reacts with the epoxy group on the surface of the fiber to form a chemical bond, the nanoparticle is firmly loaded on the surface of the fiber in the form of a point, which enhances the roughness of the fiber surface and the bonding ability of the composite interface; The film-forming emulsion has good compatibility with the epoxy-based coupling agent on the surface of the fiber, and can tightly cover the surface of the fiber in the form of a film, which enhances the strength, bundling and surface activity of the fiber.

The ordered modification treatment method constructed above can achieve better results than the disordered modification treatment in which the above-mentioned substances are directly mixed.

Description of drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the accompanying drawings used in the embodiments. It should be understood that the following drawings only show some embodiments of the present application, so should be considered as limiting the scope of the application.

Fig. 1 is the schematic diagram of the principle of the modified fiber provided by the present application;

Fig. 2 is the physical figure of the modified basalt fiber that embodiment 2 provides;

Fig. 3 is the surface topography photograph of the modified basalt fiber that embodiment 2 provides;

Fig. 4 is the physical figure of the modified fiber reinforced nylon composite material that embodiment 2 provides;

Fig. 5 is the interface topography photograph of the modified fiber reinforced nylon composite material that embodiment 2 provides;

Fig. 6 is the physical figure of the unmodified basalt fiber that comparative example 3 provides;

Fig. 7 is the surface topography photograph of the unmodified basalt fiber that comparative example 3 provides;

Fig. 8 is the physical figure of the unmodified fiber-reinforced nylon composite material that comparative example 3 provides;

FIG. 9 is a photograph of the interface morphology of the unmodified fiber-reinforced nylon composite material provided in Comparative Example 3.

detailed description

As used herein:

"Prepared from" is synonymous with "comprising". As used herein, the terms "comprises," "including," "has," "containing," or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a composition, step, method, article, or device comprising listed elements is not necessarily limited to those elements, but may include other elements not explicitly listed or inherent to such composition, step, method, article, or device. elements.

The conjunction "consisting of" excludes any unspecified elements, steps or components. If used in a claim, this phrase will make the claim closed so that it does not contain material other than those described except for the customary impurities associated therewith. When the phrase "consisting of" appears in a clause of the subject of a claim rather than immediately following the subject matter, it only defines the elements described in that clause; other elements are not excluded from the claims as a whole. beyond the claims.

When amounts, concentrations, or other values or parameters are expressed in terms of ranges, preferred ranges, or ranges bounded by a series of upper preferred values and lower preferred values, it is to be understood that any range upper or preferred value combined with any lower range limit is specifically disclosed. All ranges formed by any pairing of values or preferred values, whether or not such ranges are individually disclosed. For example, when the range "1-5" is disclosed, the described range should be construed to include the ranges "1-4", "1-3", "1-2", "1-2 and 4-5" , "1 ~ 3 and 5" and so on. When a numerical range is described herein, unless otherwise stated, that range is intended to include its endpoints and all integers and fractions within the range.

In these examples, unless otherwise specified, the stated parts and percentages are by mass.

"Parts by mass" refers to the basic measurement unit that expresses the mass ratio relationship of multiple components, and 1 part can represent any unit mass, such as 1g or 2.689g. If we say that the mass part of A component is a part, and the mass part of B component is b part, it means that the mass ratio of A component to B component is a:b. Alternatively, it means that the mass of component A is aK, and the mass of component B is bK (K is an arbitrary number, representing a multiple factor). It should not be misunderstood that, unlike the parts by mass, the sum of parts by mass of all components is not limited to 100 parts.

"And/or" is used to indicate that one or both of the stated situations may occur, for example, A and/or B includes (A and B) and (A or B).

A preparation method of modified fiber, comprising:

Mixing the first aqueous solution of glacial acetic acid and the amino coupling agent for the first time, then adding nanoparticles to carry out the first reaction, then performing the first solid-liquid separation, and the first drying to obtain modified nanoparticles;

The second glacial acetic acid aqueous solution and the epoxy-based coupling agent are mixed for the second time, and then the fiber is added for the second reaction. After the second reaction is completed, the modified nanoparticles and the film-forming emulsion are added, and the reaction is continued. second solid-liquid separation and second drying to obtain the modified fiber;

The fibers include one or more of basalt fibers, carbon fibers, glass fibers, and aramid fibers, and the nanoparticles include nano silicon dioxide and/or nano titanium dioxide.

In an optional embodiment, the mass fractions of the first aqueous glacial acetic acid solution and the second aqueous glacial acetic acid solution are independently 0.03%-0.2%.

Optionally, the mass fractions of the first aqueous glacial acetic acid solution and the second aqueous glacial acetic acid solution can be independently 0.03%, 0.05%, 0.1%, 0.15%, 0.2% or between 0.03% and 0.2%. any value.

In an optional embodiment, the preparation method meets at least one of the following conditions:

a. the amino coupling agent comprises a single amino coupling agent and/or a polyamino coupling agent;

For example, it can be γ-aminopropyltriethoxysilane (KH550), N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane (KH792), diaminosilane oligomer (DH2776), etc. ;

b. the consumption of the amino coupling agent is 0.2%-4.0% of the consumption of the water in the first glacial acetic acid aqueous solution;

c. The time for the first mixing is 0.5h-2h.

Optionally, the amount of the amino coupling agent can be 0.2%, 0.5%, 1.0%, 1.5%, 2.0%, 2.5%, 3.0%, 3.5% of the amount of water in the first glacial acetic acid aqueous solution , 4.0%, or any value between 0.2%-4.0%; the first mixing time may be 0.5h, 1.0h, 1.5h, 2h, or any value between 0.5h-2h.

In an optional embodiment, the preparation method meets at least one of the following conditions:

d. The amount of the nanoparticles is 0.5%-10% of the amount of water in the first aqueous solution of glacial acetic acid;

e. The first reaction is carried out under stirring conditions, the reaction temperature is 50°C-95°C, and the stirring time is 3h-6h.

Optionally, the amount of the nanoparticles can be 0.5%, 1.0%, 1.5%, 2.0%, 2.5%, 3.0%, 3.5%, 4.0%, 4.5% of the amount of water in the first glacial acetic acid aqueous solution %, 5.0%, 5.5%, 6.0%, 6.5%, 7.0%, 7.5%, 8.0%, 8.5%, 9.0%, 9.5%, 10% or any value between 0.5% and 10%; The reaction is carried out under stirring conditions, and the reaction temperature can be 50°C, 55°C, 60°C, 65°C, 70°C, 75°C, 80°C, 85°C, 90°C, 95°C or between 50°C and 95°C Any value, the stirring time can be 3h, 4h, 5h, 6h or any value between 3h-6h.

In an optional embodiment, the preparation method meets at least one of the following conditions:

f. the epoxy-based coupling agent includes a single epoxy-based coupling agent and/or multiple epoxy-based coupling agents;

For example: γ-glycidyl ether oxypropyl trimethoxysilane (KH560), β-(3,4-epoxycyclohexyl) ethyl trimethoxysilane (A186), polyepoxy silane oligomer (MP200 )Wait.

g. the consumption of the epoxy group coupling agent is 0.2%-4% of the consumption of the water in the second glacial acetic acid aqueous solution;

h. The time for the second mixing is 2h-6h.

Optionally, the amount of the epoxy-based coupling agent can be 0.2%, 0.5%, 1.0%, 1.5%, 2.0%, 2.5%, 3.0%, 3.5%, 4.0% or any value between 0.2%-4%; the second mixing time may be 2h, 3h, 4h, 5h, 6h or any value between 2h-6h.

In an optional embodiment, the preparation method meets at least one of the following conditions:

i. the consumption of the fiber is 5%-20% of the consumption of the water in the second glacial acetic acid aqueous solution;

j. The second reaction is carried out under the assistance of ultrasonic waves, the reaction temperature is 50°C-95°C, and the reaction time is 2h-4h;

k. The amount of the modified nanoparticles is 0.5%-2.5% of the amount of water in the second glacial acetic acid aqueous solution.

Optionally, the amount of the fiber can be any value between 5%, 10%, 15%, 20% or 5%-20% of the amount of water in the second glacial acetic acid aqueous solution; The second reaction is carried out with the assistance of ultrasonic waves, and the reaction temperature can be 50°C, 55°C, 60°C, 65°C, 70°C, 75°C, 80°C, 85°C, 90°C, 95°C or between 50°C and 95°C Any value, the reaction time can be any value between 2h, 3h, 4h or 2h-4h; The consumption of described modified nanoparticles can be 0.5% of the consumption of the water in the second glacial acetic acid aqueous solution , 1.0%, 1.5%, 2.0%, 2.5%, or any value between 0.5% and 2.5%.

In an optional embodiment, the preparation method meets at least one of the following conditions:

l. described film-forming emulsion comprises one or more in epoxy emulsion, polyester emulsion and acrylic acid emulsion;

m. the consumption of the film-forming emulsion is 1%-5% of the consumption of the water in the second glacial acetic acid aqueous solution;

n. The time for continuing the reaction is 1h-3h.

Optionally, the amount of the film-forming emulsion can be 1%, 2%, 3%, 4%, 5% or 1%-5% of the amount of water in the second glacial acetic acid aqueous solution; The reaction time can be 1h, 2h, 3h or 1h-3h.

The present application also provides a modified fiber, which is prepared by the method for preparing the modified fiber.

The present application also provides a reinforced thermoplastic composite material, including the modified fiber.

Modified fibers are used as a part or all of the raw materials for further processing to obtain reinforced thermoplastic composite materials.

The present application also provides a use of reinforced thermoplastic composite materials, which are used in the fields of aerospace, national defense and military industry, rail transportation, automobiles and ships, and new energy infrastructure.

The reinforced thermoplastic composite material provided by this application can be used in material production, equipment manufacturing, infrastructure, etc. in the fields of aerospace, national defense, rail transit, automobiles, ships, and new energy infrastructure.

The implementation of the present application will be described in detail below in conjunction with specific examples, but those skilled in the art will understand that the following examples are only used to illustrate the present application, and should not be considered as limiting the scope of the present application. Those who do not indicate the specific conditions in the examples are carried out according to the conventional conditions or the conditions suggested by the manufacturer. The reagents or instruments used were not indicated by the manufacturer, and they were all conventional products that could be purchased from the market.

Example 1

As shown in Figure 1, the present embodiment provides a modified basalt fiber, the preparation method of which is as follows:

(1) Add 0.05% mass fraction of glacial acetic acid into 2000mL deionized water, stir for 0.5h until completely dissolved;

(2) Weigh 0.2% mass fraction of γ-aminopropyltriethoxysilane (KH550) into the above acid solution, stir for 0.5h until the solution is clear;

(3) Weighing 0.5% mass fraction of nano-titanium dioxide and adding it to the above solution, stirring and reacting at 50° C. for 3 hours, filtering and drying to obtain modified nano-titanium dioxide;

(4) Add 0.05% mass fraction of glacial acetic acid into 2000mL deionized water, stir for 0.5h until completely dissolved;

(5) Weigh 0.2% mass fraction of γ-glycidyl etheroxypropyl trimethoxysilane (KH560) into the above acid solution, and stir for 2 hours until the solution is clear;

(6) Weigh 5% mass fraction of basalt fiber and add it to the above solution. After 50° C. of ultrasonic-assisted reaction for 2 hours, add 0.5% mass fraction of the modified nano-titanium dioxide obtained in step (3), and 1% mass fraction of ring Oxygen emulsion, continue to react for 1 hour, filter and dry to obtain modified basalt fiber.

Example 2

This embodiment provides a modified basalt fiber, the preparation method of which is as follows:

(1) Add 0.1% mass fraction of glacial acetic acid into 2000mL deionized water, stir for 0.5h until completely dissolved;

(2) Weigh 2% mass fraction of N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane (KH792) into the above acid solution, stir for 1 hour until the solution is clear;

(3) Weighing 5% mass fraction of nano-silica and adding it to the above solution, stirring and reacting at 75° C. for 4.5 hours, filtering and drying to obtain modified nano-silica;

(4) Add 0.1% mass fraction of glacial acetic acid into 2000mL deionized water, stir for 0.5h until completely dissolved;

(5) Weigh 2% mass fraction of β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane (A186) into the above acid solution, and stir for 4 hours until the solution is clear;

(6) Weigh 10% mass fraction of basalt fiber and add it to the above solution, after 75°C ultrasonically assisted reaction for 3 hours, then add the modified nano-silica obtained in step (3) of 1% mass fraction, and 3% mass fraction After continuing to react for 2 hours, the polyurethane emulsion was filtered and dried to obtain modified basalt fiber.

The physical picture of the obtained modified basalt fiber is shown in Figure 2, and the photo of its surface morphology is shown in Figure 3. The modified basalt fiber and nylon resin are combined to obtain the modified fiber reinforced nylon composite material, as shown in Figure 4, and the photo of the interface morphology is shown in Figure 5.

Example 3

This embodiment provides a modified basalt fiber, the preparation method of which is as follows:

(1) Add 0.2% mass fraction of glacial acetic acid into 2000mL deionized water, stir for 0.5h until completely dissolved;

(2) Weigh 4.0% mass fraction of bisaminosilane oligomer (DH2776) into the above acid solution, stir for 2 hours until the solution is clear;

(3) adding 10% mass fraction of nano-silica to the above solution, stirring and reacting at 95° C. for 6 hours, filtering and drying to obtain modified nano-silica;

(4) Add 0.2% mass fraction of glacial acetic acid into 2000mL deionized water, stir for 0.5h until completely dissolved;

(5) Add polyepoxysilane oligomer (MP200) with a mass fraction of 4.0% into the above acid solution, and stir for 6 hours until the solution is clear;

(6) Weigh 20% mass fraction of basalt fiber and add it to the above solution, after ultrasonically assisted reaction at 95°C for 4 hours, then add 2.5% mass fraction of the modified nano-silica obtained in step (3), and 5% mass fraction After continuing to react for 3 hours, the polyurethane emulsion was filtered and dried to obtain modified basalt fiber.

Example 4

The present embodiment provides a kind of modified carbon fiber, and its preparation method is as follows:

(1) Add 0.1% mass fraction of glacial acetic acid into 2000mL deionized water, stir for 0.5h until completely dissolved;

(2) Weigh 2% mass fraction of N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane (KH792) into the above acid solution, stir for 1 hour until the solution is clear;

(3) Weighing 5% mass fraction of nano-silica and adding it to the above solution, stirring and reacting at 75° C. for 4.5 hours, filtering and drying to obtain modified nano-silica;

(4) Add 0.1% mass fraction of glacial acetic acid into 2000mL deionized water, stir for 0.5h until completely dissolved;

(5) Weigh 2% mass fraction of β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane (A186) into the above acid solution, and stir for 4 hours until the solution is clear;

(6) Weighing 10% mass fraction of carbon fibers added to the above solution, after 75 ° C ultrasonically assisted reaction for 3 hours, then adding the modified nano-silica obtained in step (3) of 1% mass fraction, and 3% mass fraction of After continuing to react the polyurethane emulsion for 2 hours, filter and dry to obtain modified carbon fibers.

Example 5

This embodiment provides a modified aramid fiber, the preparation method of which is as follows:

(1) Add 0.1% mass fraction of glacial acetic acid into 2000mL deionized water, stir for 0.5h until completely dissolved;

(2) Weigh 2% mass fraction of N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane (KH792) into the above acid solution, stir for 1 hour until the solution is clear;

(3) Weighing 5% mass fraction of nano-silica and adding it to the above solution, stirring and reacting at 75° C. for 4.5 hours, filtering and drying to obtain modified nano-silica;

(4) Add 0.1% mass fraction of glacial acetic acid into 2000mL deionized water, stir for 0.5h until completely dissolved;

(5) Weigh 2% mass fraction of β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane (A186) into the above acid solution, and stir for 4 hours until the solution is clear;

(6) Weigh 10% mass fraction of aramid fiber and add it to the above solution, after ultrasonically assisted reaction at 75°C for 3 hours, then add the modified nano-silica obtained in step (3) of 1% mass fraction, and 3% mass fraction Fractions of the polyurethane emulsion, after continuing to react for 2 hours, were filtered and dried to obtain modified aramid fibers.

Example 6

The present embodiment provides a kind of modified glass fiber, and its preparation method is as follows:

(1) Add 0.1% mass fraction of glacial acetic acid into 2000mL deionized water, stir for 0.5h until completely dissolved;

(2) Weigh 2% mass fraction of N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane (KH792) into the above acid solution, stir for 1 hour until the solution is clear;

(3) Weighing 5% mass fraction of nano-silica and adding it to the above solution, stirring and reacting at 75° C. for 4.5 hours, filtering and drying to obtain modified nano-silica;

(4) Add 0.1% mass fraction of glacial acetic acid into 2000mL deionized water, stir for 0.5h until completely dissolved;

(5) Weigh 2% mass fraction of β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane (A186) into the above acid solution, and stir for 4 hours until the solution is clear;

(6) Weigh 10% mass fraction of glass fiber and add it to the above solution, after 75 °C ultrasonically assisted reaction for 3 hours, then add the modified nano-silica obtained in step (3) of 1% mass fraction, and 3% mass fraction After continuing to react for 2 hours, the polyurethane emulsion was filtered and dried to obtain modified glass fibers.

Comparative example 1

This comparative example provides a modified basalt fiber, the preparation method of which is as follows:

(1) Add 0.1% mass fraction of glacial acetic acid into 2000mL deionized water, stir for 0.5h until completely dissolved;

(2) Weigh 2% mass fraction of N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane (KH792), 5% mass fraction of nano-silica, 2% mass fraction of β- Add (3,4-epoxycyclohexyl)ethyltrimethoxysilane (A186), 10% mass fraction of basalt fiber, and 3% mass fraction of polyurethane emulsion to the above acid solution, and after 75 °C ultrasonically assisted reaction for 6 hours, filter drying to obtain modified basalt fiber.

Comparative example 2

This comparative example provides a modified basalt fiber, the preparation method of which is as follows:

(1) Add 0.1% mass fraction of glacial acetic acid into 2000mL deionized water, stir for 0.5h until completely dissolved;

(2) γ-aminopropyl triethoxysilane (KH550), 5% mass fraction of nano-silica, 10% mass fraction of basalt fiber, 3% mass fraction of polyurethane emulsion by weighing 2% mass fraction In the above acid solution, ultrasonically assisted reaction at 75° C. for 6 hours, filtered and dried to obtain modified basalt fiber.

Comparative example 3

Commercially available unmodified basalt fibers.

The physical picture of the unmodified basalt fiber is shown in Figure 6, and the photo of its surface morphology is shown in Figure 7. The unmodified fiber-reinforced nylon composite material was obtained by combining unmodified basalt fiber and nylon resin. The physical picture is shown in Figure 8, and the photo of its interface morphology is shown in Figure 9.

Comparative example 4

Commercially available unmodified carbon fibers.

Comparative example 5

Commercially available unmodified aramid fiber.

Comparative example 6

Commercially available unmodified glass fibers.

Performance tests were performed on the fibers of Examples and Comparative Examples.

Test method for monofilament tensile strength: Lay the fiber along the center line of the window frame-shaped cardboard, and fix it with epoxy glue at both ends, wherein the center opening distance of the window-shaped cardboard is 20mm, The prepared sample was solidified at 120°C for 2 hours, and after the sample was taken out and cooled to room temperature, the tensile test was performed on a tensile machine at a speed of 2mm/min.

The test method for the tensile strength of fiber-reinforced composite materials: the fiber-reinforced composite material is made into a standard dumbbell sample, and the two ends of the sample are clamped by a tensile machine, and the tensile speed is set at 10mm/min, and the tensile test is carried out.

The specific results are shown in Table 1:

Table 1 Comparison of performance parameters of fibers

After the fibers in the examples and comparative examples are modified, the properties of the fibers and the performance of the fiber-reinforced composite material are improved, which shows that the coupling agent, film-forming emulsion and nanoparticles used in the modified fibers have a great influence on the fiber strength, resin wettability, and composite properties. The bonding ability of the material interface has a positive positive effect.

The effect of the example is obviously better than that of the comparative example, indicating that the ordered structure constructed on the surface of the modified fiber has a stronger bonding effect between the surface activity of the fiber and the interface of the composite material than the disordered structure.

The modified fiber effect of embodiment 2 is better than that of embodiment 3, mainly because the molecular volume of the small molecule multifunctional coupling agent is small, the functional group density of the equal mass coupling agent is large, and the steric hindrance is small, and the moving speed is fast. In the process of fiber modification, the functional groups on the surface of the fiber have better reactivity. In the process of composite material manufacturing, it can improve the wettability of the resin to the modified fiber and the interface bonding performance, and can reduce the cavity of the composite material interface. In addition, after the modified fiber and the modified nano-particles are combined to form a chemical bond, the surface roughness of the modified fiber is improved, the interface grip force of the fiber-reinforced composite material is enhanced, and the stress transfer efficiency of the composite interface can be improved. .

Finally, it should be noted that: the above examples are only used to illustrate the technical solutions of the present application, but not to limit them; fiber-reinforced thermoplastic composite materials include resin systems such as nylon and polypropylene, and fiber-reinforced nylon composite materials are selected as examples here , mainly because nylon is a high-performance engineering plastic, which has higher strength and temperature resistance than general-purpose polypropylene resin. Nylon composite materials based on modified fiber reinforcement can highlight its performance advantages and realize high-end composite materials. Application; Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions described in the foregoing embodiments, or modify some or all of the technical features Equivalent replacement; and these modifications or replacements do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present application.

In addition, those skilled in the art will appreciate that although some embodiments herein include some features included in other embodiments but not others, combinations of features from different embodiments are meant to be within the scope of the present application. And form different embodiments. For example, in the following claims, any one of the claimed embodiments may be used in any combination. The information disclosed in the background technology section is only intended to deepen the understanding of the general background technology of the application, and should not be regarded as an acknowledgment or any form of suggestion that the information constitutes the prior art known to those skilled in the art.

Claims (10)

1. A preparation method of modified fiber, characterized in that, comprising: Mixing the first aqueous solution of glacial acetic acid and the amino coupling agent for the first time, then adding nanoparticles to carry out the first reaction, then performing the first solid-liquid separation, and the first drying to obtain modified nanoparticles; The second glacial acetic acid aqueous solution and the epoxy-based coupling agent are mixed for the second time, and then the fiber is added for the second reaction. After the second reaction is completed, the modified nanoparticles and the film-forming emulsion are added, and the reaction is continued. second solid-liquid separation and second drying to obtain the modified fiber; The fibers include one or more of basalt fibers, carbon fibers, glass fibers, and aramid fibers, and the nanoparticles include nano silicon dioxide and/or nano titanium dioxide. 2. The preparation method according to claim 1, wherein the mass fractions of the first aqueous glacial acetic acid solution and the second aqueous glacial acetic acid solution are independently 0.03%-0.2%. 3. The preparation method according to claim 1, characterized in that, at least one of the following conditions is met: a. the amino coupling agent comprises a single amino coupling agent and/or a polyamino coupling agent; b. the consumption of the amino coupling agent is 0.2%-4.0% of the consumption of the water in the first glacial acetic acid aqueous solution; c. The time for the first mixing is 0.5h-2h. 4. The preparation method according to claim 1, characterized in that, at least one of the following conditions is met: d. The amount of the nanoparticles is 0.5%-10% of the amount of water in the first aqueous solution of glacial acetic acid; e. The first reaction is carried out under stirring conditions, the reaction temperature is 50°C-95°C, and the stirring time is 3h-6h. 5. The preparation method according to claim 1, characterized in that, at least one of the following conditions is met: f. the epoxy-based coupling agent includes a single epoxy-based coupling agent and/or multiple epoxy-based coupling agents; g. the consumption of the epoxy group coupling agent is 0.2%-4% of the consumption of the water in the second glacial acetic acid aqueous solution; h. The time for the second mixing is 2h-6h. 6. The preparation method according to claim 1, characterized in that, at least one of the following conditions is met: i. the consumption of the fiber is 5%-20% of the consumption of the water in the second glacial acetic acid aqueous solution; j. The second reaction is carried out under the assistance of ultrasonic waves, the reaction temperature is 50°C-95°C, and the reaction time is 2h-4h; k. The amount of the modified nanoparticles is 0.5%-2.5% of the amount of water in the second glacial acetic acid aqueous solution. 7. The preparation method according to any one of claims 1-6, characterized in that at least one of the following conditions is met: l. described film-forming emulsion comprises one or more in epoxy emulsion, polyester emulsion and acrylic acid emulsion; m. the consumption of the film-forming emulsion is 1%-5% of the consumption of the water in the second glacial acetic acid aqueous solution; n. The time for continuing the reaction is 1h-3h. 8. A modified fiber, characterized in that it is prepared by the method for preparing modified fiber according to any one of claims 1-7. 9. A reinforced thermoplastic composite material, characterized in that it comprises the modified fiber according to claim 8. 10. A use of a reinforced thermoplastic composite material, characterized in that it is used in the fields of aerospace, national defense and military industry, rail transit, automobiles and ships, and new energy infrastructure.

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