MOFs-based material dispersion liquid, modified long fiber material, composite material and preparation method
By synthesizing the MOFs-based material dispersion in a water-based solvent and modifying the long fibers, the problem of poor dispersion of MOFs-based material is solved, the impregnation and bonding properties between the fiber and the resin are improved, and the mechanical properties of the composite material are significantly enhanced.
Patent Information
- Application Number
- CN202510632466.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-16
- Publication Date
- 2025-07-29
AI Technical Summary
The existing MOFs-based materials have poor dispersion and are difficult to form a good bond between fibers and resins. The preparation method requires high temperature and high pressure or toxic solvents, which is expensive.
A one-step method is used to synthesize MOFs-based material dispersion in a water-based solvent, and the modified long fiber material is prepared by heating, stirring and washing, and modified with polymer ligands to improve dispersion and interface bonding strength.
The uniform dispersion of MOFs-based materials on the fiber surface is achieved, which significantly improves the impregnation and bonding properties between the fiber and the resin, and improves the tensile strength and interlayer strength of the composite material.
Smart Images
Figure CN120383740A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of fiber treatment, and specifically relates to a MOFs-based material dispersion, a modified long fiber material, a composite material and a preparation method thereof. Background Art
[0002] Fiber-reinforced resin matrix composites have high strength and low weight, and are a widely used high-performance material. However, the physical and chemical properties of reinforcing fibers and resin matrices usually vary greatly, and achieving good impregnation and adhesion between fibers and resins is a major engineering problem. Common fiber modification methods, such as electrochemical oxidation and acidic reagent oxidation, generate a large amount of energy consumption and waste during the reaction process, are not easy to post-process, and easily cause surface defects of fibers, thereby reducing fiber strength and even causing problems such as fiber fracture.
[0003] In recent years, the technology of modifying carbon fibers with nanomaterials to enhance their wettability and adhesion with resins has been widely studied. Among them, MOFs materials, namely the abbreviation of Metal Organic Frameworks materials, are a class of porous crystal materials formed by the coordination bond of metal ions or metal clusters with organic ligands. Due to their high specific surface area, adjustable pore structure and rich chemical active sites, MOFs materials have received extensive attention in the fields of catalysis, gas storage and separation, sensing and material modification in recent years. Compared with other modification methods, MOFs materials can be used as reinforcements to modify long fibers without significantly reducing fiber strength, thereby improving the interfacial bonding strength between fibers and resins.
[0004] However, common MOFs-based materials often exhibit poor dispersion problems in practical applications, and are not easy to store and use. The PolyMOFs materials generated by modifying MOFs-based materials with polymer ligands have better dispersion and functionality, and are easier to store and use. However, the existing preparation methods of MOFs / PolyMOFs-based materials usually need to be synthesized under high temperature and high pressure conditions, or in an environment containing corrosive or toxic solvents, and the manufacturing cost is high. Therefore, it is particularly important to develop a simple, green, environmentally friendly, simple process and processing process, easy to post-process, low-cost and excellent treatment effect nanomaterial fiber surface modification method. Summary of the Invention
[0005] In view of the deficiencies of the prior art, the purpose of the present invention is to provide a MOFs-based material dispersion, a modified long fiber material, a composite material and a preparation method thereof, so as to solve or improve the defects existing in the prior art.
[0006] To achieve the above purpose, the present invention adopts the following technical solutions: The present invention provides a method for preparing a dispersion of MOFs-based materials, comprising the following steps: S11. Add a metal salt, an organic ligand, and a polymer ligand to a dispersion solvent. The molar ratio of the metal salt to the organic ligand is 3:1 - 1:3, and the mass fraction of the polymer ligand in the dispersion solvent is 0 wt% - 30 wt%. The dispersion solvent is an aqueous solvent. Then, perform a heating and stirring operation. The heating temperature is 20 - 80 °C, the stirring speed is 100 - 1500 r / min, and the stirring time is 12 - 72 h to ensure uniform reaction progress. S12. After the reaction is completed, perform a washing operation. The washing method is centrifugal washing or dialysis washing. The washing solvent is an aqueous solvent, and the number of washing times is 1 - 6 times to obtain a dispersion of MOFs-based materials with a mass fraction of 0.5% - 28%.
[0007] Preferably, in step S11, the metal salt is a salt containing one or more metal cations selected from zinc, copper, iron, cobalt, nickel, titanium, and chromium.
[0008] Preferably, in step S11, the organic ligand is a compound containing one or more functional groups selected from carboxyl, hydroxyl, amino, sulfonic acid group, phosphoric acid group, pyridyl, imidazolyl, mercapto, cyano, and nitro.
[0009] Preferably, in step S11, the polymer ligand is a compound obtained by grafting an organic ligand to a polymer backbone through a covalent bond, and its molecular weight is greater than 500 g / mol.
[0010] Preferably, in steps S11 and S12, the aqueous solvent is one or more of pure aqueous solution, acid-base adjusted aqueous solution, buffer solution, and organic solvent-aqueous solution mixture.
[0011] The present invention also provides a dispersion of MOFs-based materials obtained by the method for preparing a dispersion of MOFs-based materials.
[0012] The present invention also provides a method for preparing a modified long fiber material based on the dispersion of MOFs-based materials, comprising the following steps: S21. Degum the long fiber material to obtain a degummed long fiber material. S22. Activate the degummed long fiber material to obtain an activated long fiber material. S23. Immerse the activated long fiber material fully in the dispersion of MOFs-based materials for 0.5 - 12 h. After immersion, dry it to obtain a modified long fiber material.
[0013] Preferably, in step S21, the long fiber material is a filament, a tow, a tape or a woven fabric containing one or more fibers selected from the group consisting of carbon fiber, glass fiber, Kevlar fiber and basalt fiber.
[0014] Preferably, in step S21, the long fiber material is subjected to a degumming treatment to obtain the degummed long fiber material by the following specific method: First, the long fiber material is placed in a high-temperature oven at 300-600°C and heated for 5-40 minutes to remove the glue, or dispersed in an organic solution at 40-80°C and heated for 1-3 hours to remove the glue, then washed, and finally dried to obtain the degummed long fiber material.
[0015] Preferably, in step S22, the degummed long fiber material is activated to obtain the activated long fiber material by: The surface of the degummed long fiber material is activated by one or a combination of plasma treatment, electrochemical oxidation, acidic reagent oxidation, and heating oxidation to obtain an activated long fiber material.
[0016] The present invention also provides a modified long fiber material obtained by the preparation method of the modified long fiber material.
[0017] The present invention also provides a method for preparing a modified fiber-reinforced resin composite material. Based on the modified long fiber material, the modified long fiber material is completely immersed in resin for a time of 0.05-12 hours. After the impregnation is completed, the modified fiber-reinforced resin composite material is dried to obtain the modified fiber-reinforced resin composite material.
[0018] The present invention also provides a modified fiber-reinforced resin composite material, which is obtained by the preparation method of the modified fiber-reinforced resin composite material.
[0019] Compared with the prior art, the present invention has the following beneficial effects: (1) The present invention adopts a one-step method to synthesize MOF-based materials (MOF materials and / or PolyMOFs materials), which has mild reaction conditions, is green and environmentally friendly, low-cost, simple and efficient process, and is applicable to the preparation of various MOF-based materials; (2) MOFs materials have a large specific surface area and high porosity. After modification, the affinity and surface activity of carbon fibers can be significantly improved, thereby effectively improving the impregnation and bonding properties of long fibers and polymers.
[0020] (3) The polymer-bound PolyMOFs material not only retains the high specific surface area and high porosity characteristics of the MOFs material, but also provides a rich surface functional group, significantly improving the dispersibility of the MOFs-based material and reducing precipitation and agglomeration. At the same time, the affinity of the long fiber is further improved, effectively enhancing the impregnation and bonding effect between the long fiber and the polymer.
[0021] (4) By activating the surface of the debonded long fiber material, the long fiber surface is transformed from inert to active, and the smooth surface is modified to a rough surface, which can significantly improve the grafting rate of MOFs-based materials on the long fiber surface.
[0022] (5) The fiber-reinforced resin-based composite material obtained by impregnating the long fiber modified by the MOFs-based material prepared by the present invention with a resin matrix has significantly improved tensile strength and interlaminar strength. BRIEF DESCRIPTION OF THE DRAWINGS
[0023] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on the drawings in the following description without any creative work.
[0024] Figure 1 It is a schematic flow chart of a method for preparing a MOFs-based material dispersion of the present invention.
[0025] Figure 2 The figure is a schematic flow chart of a method for preparing modified long fibers according to the present invention. DETAILED DESCRIPTION
[0026] In order to make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with the drawings in the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. In order to make the above-mentioned features and advantages of the present invention more obvious and easy to understand, the following embodiments are specifically cited and described in detail with reference to the drawings.
[0027] like Figure 1 As shown, an embodiment of the present invention provides a method for preparing a MOFs-based material dispersion, comprising the following steps: S11. Add a metal salt, an organic ligand, and a polymeric ligand into a dispersion solvent. The molar ratio of the metal salt to the organic ligand is 3:1 - 1:3, the mass fraction of the polymeric ligand in the dispersion solvent is 0 wt% - 30 wt%, the dispersion solvent is an aqueous solvent, and then perform a heating and stirring operation. The heating temperature is 20 - 80 °C, the stirring speed is 100 - 1500 r / min, and the stirring time is 12 - 72 h to ensure uniform progress of the reaction. The entire reaction process is completed by a one-step method; S12. After the reaction is completed, perform a washing operation. The washing method is centrifugal washing or dialysis washing. The washing solvent is an aqueous solvent, and the number of washing times is 1 - 6 times to obtain a MOFs-based material dispersion with a mass fraction of 0.5% - 28%.
[0028] When the mass fraction of the polymeric ligand in the dispersion solvent is 0 wt%, the MOFs-based material dispersion is a MOFs material dispersion; when the mass fraction of the polymeric ligand in the dispersion solvent is greater than 0 wt%, the MOFs-based material dispersion is a polyMOFs material dispersion.
[0029] In this embodiment, in step S11, the metal salt is preferably but not limited to a salt containing one or more metal cations such as zinc, copper, iron, cobalt, nickel, titanium, chromium, etc.
[0030] In this embodiment, in step S11, the organic ligand is preferably but not limited to a compound containing one or more functional groups such as carboxyl, hydroxyl, amino, sulfonic acid group, phosphoric acid group, pyridyl, imidazolyl, mercapto, cyano, nitro, etc., such as macrocyclic compounds, porphyrins, etc.
[0031] In this embodiment, in step S11, the polymeric ligand is a compound obtained by grafting an organic ligand to a polymer backbone through a covalent bond. The polymeric ligand can be an oligomer or a polymer, and its molecular weight is preferably but not limited to greater than 500 g / mol. Among them, the organic ligand needs to contain functional groups such as carboxyl, hydroxyl, amino, sulfonic acid group, etc., such as hydroxy-containing cyclodextrin, pyridyl-containing porphyrin, etc.; the polymer is preferably but not limited to a polymer material with good dispersibility such as polyacrylic acid (PAA), polyethylene glycol (PEG), polyvinylpyrrolidone (PVP), sodium polystyrene sulfonate (PSS), etc.
[0032] In this embodiment, in steps S11 and S12, the water-based solvent is one or more of a pure aqueous solution, an acid-base-adjusted aqueous solution, a buffer solution, and an organic solvent-water mixed solution. The pure aqueous solution may be deionized water, ultrapure water, water for injection, or the like; the acid-base-adjusted aqueous solution may be an acidic aqueous solution (e.g., hydrochloric acid aqueous solution, formic acid aqueous solution, sulfuric acid aqueous solution), an alkaline aqueous solution (e.g., sodium hydroxide aqueous solution, ammonia aqueous solution), or the like; the buffer solution may be a phosphate buffer, a Tris-HCl buffer, or a carbonate buffer; and the organic solvent-water mixed solution may be a surfactant-water system (e.g., sodium lauryl sulfate aqueous solution, Tween-20 / 80 aqueous solution, polyethylene glycol aqueous solution), an organic cosolvent-water mixed system (e.g., ethanol aqueous solution, ethylene glycol aqueous solution, acetone aqueous solution), or the like.
[0033] This embodiment also provides a MOFs-based material dispersion liquid, which is obtained by the preparation method of the MOFs-based material dispersion liquid.
[0034] like Figure 2 As shown, a method for preparing a modified long fiber material, based on the MOFs-based material dispersion, comprises the following steps: S21, performing a degumming treatment on the long fiber material to obtain a degummed long fiber material; S22, activating the degummed long fiber material to obtain an activated long fiber material; S23. Fully immerse the activated long fiber material in the MOFs-based material dispersion, and graft the MOFs-based material in the MOFs-based material dispersion onto the surface of the activated long fiber material by chemical deposition. The immersion time is 0.5-12 hours. After the immersion is completed, dry to obtain a modified long fiber material.
[0035] In this embodiment, in step S21, the long fiber material is preferably, but not limited to, filaments, tows, tapes, or woven fabrics containing one or more fibers selected from carbon fiber, glass fiber, Kevlar fiber, basalt fiber, and the like.
[0036] In this embodiment, in step S21, the long fiber material is subjected to a degumming treatment to obtain the degummed long fiber material. The specific method is: First, the long fiber material is placed in a high-temperature oven at 300-600°C and heated for 5-40 minutes to remove the glue, or dispersed in an organic solution at 40-80°C and heated for 1-3 hours to remove the glue, then washed, and finally dried to obtain the degummed long fiber material.
[0037] In this embodiment, in step S22, the debonded long fiber material is activated to obtain the activated long fiber material by the following specific method: The surface of the degummed long fiber material is activated by one or a combination of plasma treatment, electrochemical oxidation, acidic reagent oxidation, and heating oxidation to obtain an activated long fiber material.
[0038] This embodiment also provides a modified long fiber material obtained by the preparation method of the modified long fiber material.
[0039] This embodiment also provides a method for preparing a modified fiber-reinforced resin composite material. Based on the modified long fiber material, the modified long fiber material is completely immersed in resin for a time of 0.05-12 hours. After the impregnation is completed, the modified fiber-reinforced resin composite material is obtained by drying.
[0040] In this embodiment, the resin is a thermosetting resin or a thermoplastic resin, such as epoxy resin, polyamide, PEEK, PA6, PA12, etc.
[0041] This embodiment also provides a modified fiber-reinforced resin composite material, which is obtained by the preparation method of the modified fiber-reinforced resin composite material.
[0042] Example 1: A method for preparing a MOFs-based material dispersion, comprising the following steps: S11, copper salt and trimesic acid (BTC) were added to water, with a molar ratio of copper salt to trimesic acid of 3:1, and then heated and stirred at a heating temperature of 20°C, a stirring speed of 100 r / min, and a stirring time of 12 h to ensure uniform reaction. The entire reaction process was completed in a one-step process; S12. After the reaction is completed, a washing operation is performed. The washing method is centrifugal washing or dialysis washing. Centrifugal washing is performed three times with water and ethanol respectively. The unreacted upper layer liquid is discarded each time, and the lower layer liquid is retained. The two layers are combined to obtain a MOF-based material dispersion liquid with a mass fraction of 0.5%. The MOF-based material dispersion liquid at this time is the MOF material dispersion liquid.
[0043] This embodiment also provides a MOFs-based material dispersion liquid, which is obtained by the preparation method of the MOFs-based material dispersion liquid.
[0044] like Figure 2 As shown, a method for preparing a modified long fiber material, based on the MOFs-based material dispersion, comprises the following steps: S21, performing a degumming treatment on the long fiber material to obtain a degummed long fiber material; S22, activating the degummed long fiber material to obtain an activated long fiber material; S23. Fully immerse the activated long fiber material in the MOFs-based material dispersion for 0.5 h. Dry after immersion to obtain a modified long fiber material.
[0045] In this embodiment, in step S21, the long fiber material is subjected to a degumming treatment to obtain the degummed long fiber material. The specific method is: First, the long fiber material was placed in a high-temperature oven at 300°C for 5 minutes to remove the glue, then washed with water and ethanol three times respectively, and finally dried to obtain the degummed long fiber material.
[0046] In this embodiment, in step S22, the debonded long fiber material is activated to obtain the activated long fiber material by the following specific method: The surface of the debonded long fiber material was activated by plasma treatment to obtain an activated long fiber material. The activation treatment specifically comprises the following steps: introducing air at a gas flow rate of 30 mL / min into a plasma torch apparatus, placing the debonded long fiber material 1.2 cm below the flame of the plasma torch apparatus at a voltage of 84 V and a current of 1 A, and treating for 5 minutes to obtain the activated long fiber material.
[0047] This embodiment also provides a modified long fiber material obtained by the preparation method of the modified long fiber material.
[0048] This embodiment also provides a method for preparing a modified fiber-reinforced resin composite material. Based on the modified long fiber material, the modified long fiber material is completely immersed in resin for 0.05 h. After the impregnation, the modified fiber-reinforced resin composite material is obtained by drying.
[0049] This embodiment also provides a modified fiber-reinforced resin composite material, which is obtained by the preparation method of the modified fiber-reinforced resin composite material.
[0050] Example 2: A method for preparing a MOFs-based material dispersion, comprising the following steps: S11, adding copper salt, trimesic acid (BTC) and polyacrylic acid-modified trimesic acid (PAA-BTC) to water, wherein the molar ratio of copper salt to trimesic acid is 1:1 and the mass fraction of polyacrylic acid-modified trimesic acid in water is 10 wt %, and then heating and stirring are performed at a heating temperature of 60° C., a stirring speed of 800 rpm, and a stirring time of 48 h to ensure uniform reaction. The entire reaction process is completed in a one-step process; S12. After the reaction is completed, a washing operation is performed. The washing method is centrifugal washing or dialysis washing. Centrifugal washing is performed three times with water and ethanol respectively. The unreacted upper layer liquid is discarded each time, and the lower layer liquid is retained. The two layers are combined to obtain a MOF-based material dispersion with a mass fraction of 8%. At this time, the MOF-based material dispersion is a polyMOF material dispersion.
[0051] This embodiment also provides a MOFs-based material dispersion liquid, which is obtained by the preparation method of the MOFs-based material dispersion liquid.
[0052] like Figure 2 As shown, a method for preparing a modified long fiber material, based on the MOFs-based material dispersion, comprises the following steps: S21, performing a degumming treatment on the long fiber material to obtain a degummed long fiber material; S22, activating the degummed long fiber material to obtain an activated long fiber material; S23. Fully immerse the activated long fiber material in the MOFs-based material dispersion for 6 hours. Dry after immersion to obtain a modified long fiber material.
[0053] In this embodiment, in step S21, the long fiber material is subjected to a degumming treatment to obtain the degummed long fiber material. The specific method is: First, the long fiber material was placed in a high-temperature oven at 400°C for 15 minutes to remove the glue, then washed once with water and ethanol respectively, and finally dried to obtain the degummed long fiber material.
[0054] In this embodiment, in step S22, the debonded long fiber material is activated to obtain the activated long fiber material by the following specific method: The surface of the debonded long fiber material is activated by conventional electrochemical oxidation to obtain an activated long fiber material.
[0055] This embodiment also provides a modified long fiber material obtained by the preparation method of the modified long fiber material.
[0056] This embodiment also provides a method for preparing a modified fiber-reinforced resin composite material. Based on the modified long fiber material, the modified long fiber material is completely immersed in resin for 6 hours. After the impregnation, the modified fiber-reinforced resin composite material is obtained by drying.
[0057] This embodiment also provides a modified fiber-reinforced resin composite material, which is obtained by the preparation method of the modified fiber-reinforced resin composite material.
[0058] Example 3: A method for preparing a MOFs-based material dispersion, comprising the following steps: S11, adding copper salt, trimesic acid (BTC) and polyacrylic acid-modified trimesic acid (PAA-BTC) to water, wherein the molar ratio of copper salt to trimesic acid is 1:1 and the mass fraction of polyacrylic acid-modified trimesic acid in water is 20 wt %, and then heating and stirring are performed at a heating temperature of 40° C., a stirring speed of 1000 r / min, and a stirring time of 60 h to ensure uniform reaction. The entire reaction process is completed in a one-step process; S12. After the reaction is completed, a washing operation is performed. The washing method is centrifugal washing or dialysis washing. The washing is performed three times with water and ethanol respectively. The unreacted upper layer liquid is discarded each time, and the lower layer liquid is retained. The two layers are combined to obtain a MOF-based material dispersion with a mass fraction of 18%. At this time, the MOF-based material dispersion is a polyMOF material dispersion.
[0059] This embodiment also provides a MOFs-based material dispersion liquid, which is obtained by the preparation method of the MOFs-based material dispersion liquid.
[0060] like Figure 2 As shown, a method for preparing a modified long fiber material, based on the MOFs-based material dispersion, comprises the following steps: S21, performing a degumming treatment on the long fiber material to obtain a degummed long fiber material; S22, activating the degummed long fiber material to obtain an activated long fiber material; S23. Fully immerse the activated long fiber material in the MOFs-based material dispersion for 10 hours. Dry after immersion to obtain a modified long fiber material.
[0061] In this embodiment, in step S21, the long fiber material is subjected to a degumming treatment to obtain the degummed long fiber material. The specific method is: First, the long fiber material was placed in a high-temperature oven at 400°C for 30 minutes to remove the glue, then washed twice with water and ethanol respectively, and finally dried to obtain the degummed long fiber material.
[0062] In this embodiment, in step S22, the debonded long fiber material is activated to obtain the activated long fiber material by the following specific method: The surface of the debonded long fiber material was activated by plasma treatment to obtain an activated long fiber material. The activation treatment specifically comprises the following steps: introducing air at a gas flow rate of 30 mL / min into a plasma torch apparatus, placing the debonded long fiber material 1.2 cm below the flame of the plasma torch apparatus at a voltage of 84 V and a current of 1 A, and treating for 5 minutes to obtain the activated long fiber material.
[0063] This embodiment also provides a modified long fiber material obtained by the preparation method of the modified long fiber material.
[0064] This embodiment also provides a method for preparing a modified fiber-reinforced resin composite material. Based on the modified long fiber material, the modified long fiber material is completely immersed in resin for 10 hours. After the impregnation, the modified fiber-reinforced resin composite material is obtained by drying.
[0065] This embodiment also provides a modified fiber-reinforced resin composite material, which is obtained by the preparation method of the modified fiber-reinforced resin composite material.
[0066] Example 4: A method for preparing a MOFs-based material dispersion, comprising the following steps: S11, adding copper salt, trimesic acid (BTC) and polyacrylic acid-modified trimesic acid (PAA-BTC) to water, wherein the molar ratio of copper salt to trimesic acid is 1:3 and the mass fraction of polyacrylic acid-modified trimesic acid in water is 30 wt %, and then heating and stirring are performed at a heating temperature of 20° C., a stirring speed of 1500 r / min, and a stirring time of 72 h to ensure uniform reaction. The entire reaction process is completed in a one-step process; S12. After the reaction is completed, a washing operation is performed. The washing method is centrifugal washing or dialysis washing. The washing is performed three times with water and ethanol respectively. The unreacted upper layer liquid is discarded each time, and the lower layer liquid is retained. The two layers are combined to obtain a MOF-based material dispersion with a mass fraction of 28%. At this time, the MOF-based material dispersion is a polyMOF material dispersion.
[0067] This embodiment also provides a MOFs-based material dispersion liquid, which is obtained by the preparation method of the MOFs-based material dispersion liquid.
[0068] like Figure 2 As shown, a method for preparing a modified long fiber material, based on the MOFs-based material dispersion, comprises the following steps: S21, performing a degumming treatment on the long fiber material to obtain a degummed long fiber material; S22, activating the degummed long fiber material to obtain an activated long fiber material; S23. Fully immerse the activated long fiber material in the MOFs-based material dispersion liquid for 12 h. After the immersion, dry it to obtain the modified long fiber material.
[0069] In this embodiment, in step S21, the specific method for degumming the long fiber material to obtain the degummed long fiber material is as follows: First, place the long fiber material in a high-temperature oven at 600 °C and heat it for 40 min for degumming. Subsequently, wash it three times with water and ethanol respectively, and finally dry it to obtain the degummed long fiber material.
[0070] In this embodiment, in step S22, the specific method for activating the degummed long fiber material to obtain the activated long fiber material is as follows: Adopt the conventional electrochemical oxidation method to activate the surface of the degummed long fiber material to obtain the activated long fiber material.
[0071] This embodiment also provides a modified long fiber material obtained by the preparation method of the modified long fiber material.
[0072] This embodiment also provides a preparation method of a modified fiber-reinforced resin composite material. Based on the modified long fiber material, completely immerse the modified long fiber material in the resin for 12 h. After the immersion, dry it to obtain the modified fiber-reinforced resin composite material.
[0073] This embodiment also provides a modified fiber-reinforced resin composite material obtained by the preparation method of the modified fiber-reinforced resin composite material.
[0074] Comparative Example 1: A preparation method of a fiber-reinforced resin composite material. Completely immerse the unmodified long fiber material in the resin for 12 h. After the immersion, dry it to obtain the fiber-reinforced resin composite material.
[0075] Product testing: Use the preparation methods of the modified fiber-reinforced resin composite materials in Examples 1-4 to process different long fiber materials respectively, and test the porosity and tensile strength of the obtained modified fiber-reinforced resin composite materials. The test results are shown in Table 1.
[0076] Among them, the porosity is obtained by observing the cross-section of the modified fiber-reinforced resin composite material with a metallographic microscope and calculating the ratio of the pore volume to the cross-sectional area; the tensile strength is measured by a single-filament tensile experiment.
[0077] Table 1 Test results of the modified fiber-reinforced resin composite material: As can be seen from Table 1 and Table 2, the porosity of the modified fiber-reinforced resin composite material obtained by impregnating the resin with the MOF-based material-modified fiber of the present invention is significantly reduced, and its mechanical properties such as tensile strength are effectively enhanced, indicating that the long fiber material modified based on the MOF-based material of the present invention can significantly improve the wettability and mechanical properties of the fiber material surface, and the wetting effect is good.
[0078] In addition, through transmission electron microscopy (TEM) and dynamic light scattering (DLS) experiments, it was found that: as the mass fraction of polyacrylic acid-modified trimesic acid in water increases, the dispersion effect of the MOF-based material gradually enhances, and the particle size also gradually decreases. Therefore, the higher the content of the polymer ligand, the smaller the particle size of the MOF-based material, the stronger the dispersion effect of the MOF-based material, and the better the contact uniformity between the MOF-based material and the long fiber material.
[0079] The modified long fiber with high surface energy prepared by the method of the present invention can significantly improve the surface roughness of the long fiber and the overall strength of the long fiber by its MOF-based material, effectively solving the problems existing in the existing long fiber surface modification methods, such as reducing the strength of the long fiber, complex process, environmental pollution, high cost, etc. The tensile strength, interlaminar strength and interfacial bonding strength of the fiber-reinforced resin matrix composite material formed by the composite of the MOF-based material-modified long fiber and the resin matrix have been significantly improved.
[0080] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.
Claims
1. A method for preparing a dispersion of MOFs-based material, characterized in that, It includes the following steps: S11. Add metal salt, organic ligand and polymer ligand into a dispersion solvent. The molar ratio of the metal salt to the organic ligand is 3:1 - 1:3, the mass fraction of the polymer ligand in the dispersion solvent is 0 wt% - 30 wt%, the dispersion solvent is an aqueous solvent. Then, perform a heating and stirring operation. The heating temperature is 20 - 80 °C, the stirring speed is 100 - 1500 r / min, and the stirring time is 12 - 72 h to ensure the uniform progress of the reaction. S12. After the reaction ends, perform a washing operation. The washing method is centrifugal washing or dialysis washing. The washing solvent is an aqueous solvent, and the number of washing times is 1 - 6 times to obtain a MOFs-based material dispersion with a mass fraction of 0.5% - 28%.
2. The preparation method of the MOFs-based material dispersion liquid according to claim 1, characterized in that In step S11, the metal salt is a salt containing one or more metal cations among zinc, copper, iron, cobalt, nickel, titanium, and chromium; the organic ligand is a compound containing one or more functional groups among carboxyl, hydroxyl, amino, sulfonic acid group, phosphoric acid group, pyridyl, imidazolyl, mercapto, cyano, and nitro; the polymer ligand is a compound obtained by grafting the organic ligand onto the polymer backbone through a covalent bond, and its molecular weight is greater than 500 g / mol. In steps S11 and S12, the aqueous solvent is one or more of pure aqueous solution, acid-base adjusted aqueous solution, buffer solution, and organic solvent - water mixed solution.
3. A MOFs-based material dispersion obtained by the preparation method of the MOFs-based material dispersion according to any one of claims 1 to 2.
4. A preparation method of a modified long fiber material, based on the MOFs-based material dispersion liquid as described in claim 3, characterized in that, It includes the following steps: S21. Degum the long fiber material to obtain a degummed long fiber material. S22. Activate the degummed long fiber material to obtain an activated long fiber material. S23. Immerse the activated long fiber material fully in the MOFs-based material dispersion for 0.5 - 12 h. After immersion, dry it to obtain a modified long fiber material.
5. The preparation method of the modified long fiber material according to claim 4, characterized in that, In step S21, the long fiber material is a wire, tow, strip, or woven fabric containing one or more fibers among carbon fiber, glass fiber, Kevlar fiber, and basalt fiber.
6. The preparation method of the modified long fiber material according to claim 4, wherein, In step S21, the specific method for degumming the long fiber material to obtain a degummed long fiber material is as follows: First, place the long fiber material in a high-temperature oven at 300 - 600 °C and heat it for 5 - 40 min for degumming or disperse it in an organic solution at 40 - 80 °C and heat it for 1 - 3 h for degumming. Then, wash it, and finally dry it to obtain a degummed long fiber material.
7. The preparation method of the modified long fiber material according to claim 4, characterized in that, In step S22, the specific method for activating the degummed long fiber material to obtain an activated long fiber material is as follows: Use a combination of one or several methods among plasma treatment, electrochemical oxidation, acidic reagent oxidation, and heat oxidation to activate the surface of the degummed long fiber material to obtain an activated long fiber material.
8. A modified long fiber material obtained by the preparation method of the modified long fiber material according to any one of claims 4 to 7.
9. A preparation method of a modified fiber-reinforced resin composite material, based on the modified long fiber material as described in claim 8, characterized in that: Completely immerse the modified long fiber material in the resin for 0.05 - 12 h, and after immersion, dry it to obtain a modified fiber-reinforced resin composite material.
10. A modified fiber-reinforced resin composite material obtained by the preparation method of the modified fiber-reinforced resin composite material as described in claim 9.