ZnO nanorod-based basalt fabric and PLA film composite material and preparation method thereof

Abstract

The invention discloses a basalt fabric and PLA film composite material based on ZnO nanorods and a preparation method of the basalt fabric and PLA film composite material, and relates to the field of fibers. Preparing a dopamine solution, a seed solution and a generation solution; dipping the basalt fiber fabric subjected to surface desizing into the dopamine suspension to obtain a fiber fabric wrapped by dopamine; placing the fiber fabric wrapped by the dopamine in a seed solution to obtain a fiber fabric with a seed layer; the fiber fabric with the seed layer is placed in a growth solution, and ZnO-loaded fiber fabric is obtained through ultrasonic-assisted growth; carrying out hot press molding on the ZnO-loaded fiber fabric and a PLA film to obtain a composite material, and carrying out ultrasonic-assisted growth on the composite material to obtain the ZnO-loaded fiber fabric; and carrying out hot press molding on the ZnO-loaded fiber fabric and a PLA film to obtain the composite material. According to the method, high-density, uniform coverage and rapid growth of the ZnO nanorods are realized.

Description

Technical Field

[0001] The present invention relates to the field of nanomaterial modified reinforced fibers, and in particular to a composite material of basalt fabric and PLA film based on ZnO nanorods and a preparation method thereof. Background Art

[0002] In recent years, the modification of reinforcing fibers with nanomaterials to enhance interfacial bonding has become an important approach to improve the overall mechanical properties of composite materials. Among them, ZnO nanostructures have attracted widespread attention in fiber-matrix interface reinforcement due to their excellent mechanical strength, thermal stability, and highly controllable growth.

[0003] Existing technologies mostly use traditional hydrothermal methods to synthesize ZnO nanorods. Since traditional hydrothermal methods often use zinc salt immersion in ethanol, the seed layer has poor stability and is easily detached during subsequent growth or curing, resulting in uneven ZnO distribution. In addition, slight deviations in temperature, pH and precursor concentration will cause significant differences in the morphology and orientation of the nanorods, resulting in strong dependence on process parameters. Traditional curing mostly uses high-temperature and long-term treatment, which does not match the PLA lamination temperature window, and has low cycle efficiency, making it difficult to scale up.

[0004] Therefore, the existing preparation methods have limitations such as crystal shedding, uneven size distribution, long process cycle and strong dependence on process parameters, which makes it difficult to meet the needs of industrial-scale production.

[0005] Therefore, an improved hydrothermal process is urgently needed to achieve high density, uniform coverage and rapid growth of ZnO nanorods, which is of great significance for improving the mechanical properties of PLA-based (polylactic acid) composites. Summary of the Invention

[0006] One object of the present invention is to provide a method for preparing a composite material of basalt fabric and PLA film based on ZnO nanorods, which enhances adhesion based on dopamine self-assembly and grows ZnO nanorods at a high uniformity and low temperature hydrothermally under the action of an ultrasonic field, thereby achieving high density, uniform coverage and rapid growth of ZnO nanorods.

[0007] Another object of the present invention is to provide a composite material of basalt fabric and PLA film based on ZnO nanorods.

[0008] The first object of the invention comprises the following steps:

[0009] The following steps are involved:

[0010] obtaining a surface-desized basalt fiber fabric;

[0011] preparing a dopamine solution, a seed solution, and a generating solution;

[0012] The desized basalt fiber fabric was immersed in a dopamine suspension to obtain a dopamine-coated fiber fabric; the dopamine suspension included dopamine and Tris-HCl buffer (pH = 8.5). Dopamine was oxidatively polymerized in alkaline Tris-HCl buffer to form an adhesion layer, providing a large number of -NH2 / -OH active groups, achieving covalent / coordinate binding with Zn²⁺ and the hydroxyl groups on the fiber surface, thereby improving the stability of the seed layer.

[0013] placing the dopamine-wrapped fiber fabric in a seed solution to obtain a fiber fabric with a seed layer;

[0014] The fiber fabric with the seed layer is placed in a growth solution, and the ZnO-loaded fiber fabric is grown by ultrasound-assisted growth;

[0015] The ZnO-loaded fiber fabric and the PLA film are hot-pressed to obtain a composite material.

[0016] Among them, the surface desizing treatment removed the original impregnating agent of the basalt fiber, and an active adhesion layer was formed by wrapping it with a dopamine suspension, which promoted the uniform deposition of the subsequent ZnO seed layer. The ultrasonic-assisted growth process was combined to tightly anchor the ZnO nanostructure.

[0017] ZnO crystals and PLA films form a physical interlocking structure through hot pressing, which can effectively enhance the interface shear strength compared with traditional composite materials.

[0018] Furthermore, the ZnO-loaded fiber fabric and PLA film were thermoformed and stacked at a 45-degree angle. After stacking, they were subjected to graded pressurization and cured at 110-150°C to obtain a composite material. The graded pressurization specifically included applying pressures of 10 bar, 20 bar, 30 bar, and 40 bar at 180°C, with each pressurization lasting at least 10 minutes.

[0019] Basalt fiber fabric and PLA film are stacked at a 45° angle to optimize anisotropic mechanical properties and reduce interlayer stress concentration. The pressure gradient is used to expel interlayer bubbles and enhance interfacial bonding strength. In addition, graded pressurization is used to relieve residual stress and ensure sufficient infiltration of the interface between the film and fiber fabric.

[0020] Preferably, after graded pressurization, curing is performed at 120° C. for 20 min to match the glass transition temperature of PLA, thereby achieving in-situ interfacial bonding.

[0021] Compared with existing technologies, existing technologies only focus on fiber surface modification and nanostructure loading, and do not make substantial restrictions on the stacking angle and sequence. The unclear stacking angle will lead to chaotic stress transfer paths between different fiber layers, and the directional arrangement effect of nanostructure loading will be difficult to achieve, which will in turn cause local stress concentration. Moreover, different stacking sequences may affect the interface bonding state between the fiber and the matrix and nanoparticles, resulting in interface stratification or nanoparticle agglomeration, thereby reducing mechanical properties.

[0022] Furthermore, existing technologies generally limit stacking to 0° or 90° symmetrically. However, such a setting may result in weak shear or torsional forces, leading to the problem of easy delamination between layers.

[0023] The basalt fiber fabric and the PLA film of the present invention are stacked in an alternating manner at 45 degrees, and the ZnO-loaded fiber fabric and the PLA film are thermocompression-molded and stacked in an alternating manner at 45 degrees to form at least 7 layers.

[0024] Fiber layers with an angle of ±45° can evenly withstand and distribute tensile and shear loads, avoiding the interlayer delamination or crack concentration problems caused by high concentrated stress between individual layers in symmetrical stacking at 0° or 90°. Furthermore, the interfacial discontinuities created by the staggered layer arrangement of the present invention can guide crack deflection and dissipate energy, thereby increasing the resistance to crack propagation between layers and achieving a crack deflection and pinning effect. Furthermore, balanced, symmetrical stacking at ±45° reduces edge stress concentration and improves interlayer shear strength.

[0025] Secondly, the 7-layer design can meet the minimum thickness requirements of the hot pressing process, ensuring uniform pressure transmission and full fusion between layers. The multi-layer structure can compensate for local micropores or poor bonding areas through redundant layers, thereby improving the reliability of the finished product.

[0026] Furthermore, basalt fiber surfaces typically contain a wetting agent to improve processing performance, but this agent must be removed chemically or physically (such as acid / alkali treatment or ultrasonic cleaning) to enhance the adhesion of subsequent coatings. Desizing increases the roughness of the fiber surface, facilitating uniform dopamine coating coverage. Specifically, obtaining a desizing basalt fiber fabric includes the following steps:

[0027] The basalt fiber fabric was placed in an air atmosphere tube furnace, heated to 500°C and held there, then cooled to room temperature to complete high-temperature desizing. The desizing was then immersed in an acetone-isopropanol mixed solution, subjected to ultrasonic vibration, and dried to obtain a surface-desized basalt fiber fabric. The acetone-isopropanol mixed solution contained a volume ratio of acetone to isopropanol of 3:1.

[0028] Furthermore, the seed solution includes zinc acetate, sodium lauryl sulfate, and NaOH.

[0029] The dopamine-wrapped fiber fabric was placed in the seed solution for 30 min, filtered at room temperature, and then oven-cured at 150 °C for 60 min to obtain a fiber fabric with a seed layer.

[0030] The fiber fabric with the seed layer was placed in a growth solution, ultrasonically activated, and reacted at 55-80°C for 15-30 minutes. After the reaction, the fabric was washed at room temperature and then dried at 80°C for 6 hours to obtain the ZnO-loaded fiber fabric. Sodium dodecyl sulfate and sodium hydroxide (NaOH) were used to form zinc acetate micelles, which regulated the size and dispersion of the seed cores, ensuring uniform distribution and strong attachment of the ZnO cores to the PDA layer and minimizing subsequent shedding. The growth solution consisted of an ethanol-water mixture, zinc nitrate, and hexamethylenetetramine.

[0031] Preferably, the fiber fabric with the seed layer is placed in a growth solution, and an ultrasonic field of 40 kHz, 3 W / cm² is turned on.

[0032] Among them, the ultrasonic field (40 kHz, 3 W / cm²) at 55-80°C can form a cavitation effect, promoting precursor microfluidic convection and interfacial solute exchange, accelerating the directional growth of ZnO nanorods, and achieving rapid growth and uniform high-density distribution in 15-30 minutes. Compared with traditional high-temperature and long-time processes (>90°C, several hours), it is compatible with PLA lamination conditions and reduces energy consumption and time.

[0033] Furthermore, the present invention also proposes a second invention object, which is to use the above preparation method to prepare a composite material of basalt fabric based on ZnO nanorods and PLA film.

[0034] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0035] The present invention discloses a composite material of basalt fabric and PLA film based on ZnO nanorods and a preparation method thereof. This method improves upon the hydrothermal process to achieve high-density, uniform coverage, and rapid growth of the ZnO nanorods. Specifically, the present invention accelerates the directional growth of ZnO nanorods, achieving rapid growth and uniform, high-density distribution within 15-30 minutes. Compared to existing processes, it is compatible with PLA lamination conditions and reduces energy consumption and time.

[0036] At the same time, the present invention can improve the mechanical properties of PLA-based (polylactic acid) composite materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, constitute a part of this application, and do not constitute a limitation of the embodiments of the present invention. In the drawings:

[0038] Figure 1Figure 2 is the SEM image of the basalt fiber surface, where Figure (a) is the SEM image of the basalt fiber surface; Figure (b) is the SEM image of the basalt fiber surface at high magnification;

[0039] Figure 2 Schematic diagram of tensile strength of Examples 1-7;

[0040] Figure 3 Schematic diagram of bending strength of Examples 1-7;

[0041] Figure 4 Schematic diagram of interlaminar shear strength of Examples 1-7. DETAILED DESCRIPTION

[0042] To make the objectives, technical solutions, and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the following examples and accompanying drawings. However, the present invention is not limited to the scope of the examples. Experimental methods in the following examples where specific conditions are not specified were performed according to conventional methods and conditions or selected according to the product specifications.

[0043] The endpoints of the ranges and any values ​​disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoints of each range, the endpoints of each range and individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered to be specifically disclosed herein. Example 1

[0044] A method for preparing a composite material of basalt fabric and PLA film based on ZnO nanorods comprises the following steps:

[0045] Step 1: obtaining a basalt fiber fabric with desizing on the surface;

[0046] Step 11: placing the basalt fiber fabric in an air atmosphere tubular furnace, heating it to 500°C at a heating rate of 10°C / min, holding it at 500°C for 6 hours, and then cooling it to room temperature at a rate of 20°C / min to complete high-temperature desizing;

[0047] In step 12, the basalt fiber fabric after high-temperature desizing is immersed in an acetone-isopropanol mixed solution for ultrasonic vibration, and then dried to obtain a surface-desized basalt fiber fabric. The acetone-isopropanol mixed solution has a volume ratio of acetone to isopropanol of 3:1.

[0048] Step 2, preparing a dopamine solution, a seed solution and a generating solution;

[0049] Step 21, the dopamine suspension includes 2.0 mg / mL dopamine and 10 mM Tris-HCl buffer (pH = 8.5);

[0050] 2.0 mg / mL dopamine and 10 mM Tris–HCl buffer were magnetically stirred at room temperature for 1 h to obtain a dopamine suspension;

[0051] Step 22, the seed solution includes 0.1 M zinc acetate, 0.02 M sodium lauryl sulfate, and NaOH;

[0052] 0.1 M zinc acetate and 0.02 M sodium lauryl sulfate were mixed to obtain a mixed solution, and NaOH solution was added to the mixed solution and stirred uniformly to obtain a seed solution, wherein the volume ratio of NaOH solution to the mixed solution was 1:1;

[0053] In step 23 , the growth solution includes an ethanol-water mixed solution, 0.2 M zinc nitrate, and 0.1 M hexamethylenetetramine.

[0054] The growth solution was prepared by mixing an ethanol-water mixture containing ethanol and water in a volume ratio of 1:3, 0.2 M zinc nitrate, and 0.1 M hexamethylenetetramine under a 3 W / cm² ultrasonic field (40 kHz);

[0055] Step 3, immersing the surface-desized basalt fiber fabric in a dopamine suspension for 30 minutes, filtering at room temperature and drying at 90° C. for 4 hours to obtain a dopamine-coated fiber fabric;

[0056] Step 4, placing the dopamine-coated fiber fabric in the seed solution for 30 minutes, filtering at room temperature, and then curing in an oven at 150° C. for 60 minutes to obtain a fiber fabric with a seed layer;

[0057] Step 5: placing the fiber fabric with the seed layer in a growth solution, turning on a 40 kHz, 3 W / cm² ultrasonic field, ultrasonically reacting at 65°C for 20 minutes, washing at room temperature, and drying at 80°C for 6 hours to obtain a ZnO-loaded fiber fabric;

[0058] Step 6: The ZnO-loaded fiber fabric and the PLA film are hot-pressed and stacked in 7 layers at a 45-degree angle. After stacking, they are subjected to graded pressurization and cured at 110-150°C to obtain a composite material. The graded pressurization specifically includes pressurizing at 180°C at 10 bar, 200 bar, 30 bar, and 40 bar, and each pressurization time is 10 minutes.

[0059] Among them, the total thickness of the composite material is H, H=h1+ h2+ h3+ h4+ h5+ h6+ h7;

[0060] The first layer n1 is a ZnO-loaded fiber fabric, the second layer n2 is a PLA film, the third layer n3 is a ZnO-loaded fiber fabric, the fourth layer n4 is a PLA film, the fifth layer n5 is a ZnO-loaded fiber fabric, the sixth layer n6 is a PLA film, and the seventh layer n7 is a ZnO-loaded fiber fabric. n1-n7 are stacked at a 45-degree angle; h1-h7 are the corresponding thicknesses of n1-n7 after pressurized curing.

[0061] In this embodiment, h1, h3, h5, and h7 are all 0.15 mm, h2, h4, and h6 are all 0.20 mm, and H is 1.20 mm. Example 2

[0062] Based on Example 1, in step 6, the ZnO-loaded fiber fabric and the PLA film are hot-pressed and stacked in 7 layers at 0 degrees in an alternating manner. After stacking, they are subjected to graded pressurization and cured at 110-150°C to obtain a composite material, wherein the graded pressurization specifically includes pressurizing at 180°C at 10 bar, 20 bar, 30 bar and 40 bar, and each pressurization time is 10 minutes. Example 3

[0063] Based on Example 1, in step 6, the ZnO-loaded fiber fabric and the PLA film were hot-pressed and stacked in 7 layers at a 90-degree angle. After stacking, they were subjected to graded pressurization and cured at 110-150°C to obtain a composite material, wherein the graded pressurization specifically included pressurizing at 180°C at 10 bar, 20 bar, 30 bar, and 40 bar, and each pressurization time was 10 minutes. Example 4

[0064] Based on Example 1, in step 6, the ZnO-loaded fiber fabric and the PLA film are hot-pressed and stacked in two layers at a 45-degree angle. After stacking, they are subjected to graded pressurization and cured at 110-150°C to obtain a composite material, wherein the graded pressurization specifically includes pressurizing at 180°C at 10 bar, 20 bar, 30 bar and 40 bar, and each pressurization time is 10 minutes. Example 5

[0065] Based on Example 1, in step 6, the ZnO-loaded fiber fabric and the PLA film were hot-pressed and stacked in 7 layers at a 45-degree staggered angle. After stacking, they were subjected to graded pressurization and cured at 110-150°C to obtain a composite material, wherein the graded pressurization specifically included pressurizing at 180°C at 10 bar, 25 bar, 40 bar and 55 bar, and each pressurization time was 10 minutes. Example 6

[0066] On the basis of Example 1, h1, h3, h5, and h7 are all 0.15 mm, h2, h4, and h6 are all 0.35 mm, and H is 1.65 mm. Example 7

[0067] Based on Example 1, a method for preparing a composite material of basalt fabric based on ZnO nanorods and PLA film comprises the following steps:

[0068] Step 1: obtaining a basalt fiber fabric with desizing on the surface;

[0069] Step 11: placing the basalt fiber fabric in an air atmosphere tubular furnace, heating it to 500°C at a heating rate of 10°C / min, holding it at 500°C for 6 hours, and then cooling it to room temperature at a rate of 20°C / min to complete high-temperature desizing;

[0070] In step 12, the basalt fiber fabric after high-temperature desizing is immersed in an acetone-isopropanol mixed solution for ultrasonic vibration, and then dried to obtain a surface-desized basalt fiber fabric. The acetone-isopropanol mixed solution has a volume ratio of acetone to isopropanol of 3:1.

[0071] Step 2, preparing a seed solution and a generating solution;

[0072] Step 21, the seed solution includes 0.1 M zinc acetate, 0.02 M sodium lauryl sulfate, and NaOH;

[0073] 0.1 M zinc acetate and 0.02 M sodium lauryl sulfate were mixed to obtain a mixed solution, and NaOH solution was added to the mixed solution and stirred uniformly to obtain a seed solution, wherein the volume ratio of NaOH solution to the mixed solution was 1:1;

[0074] In step 22, the growth solution includes an ethanol-water mixed solution, 0.2 M zinc nitrate, and 0.1 M hexamethylenetetramine.

[0075] The growth solution was prepared by mixing an ethanol-water mixture containing ethanol and water in a volume ratio of 1:3, 0.2 M zinc nitrate, and 0.1 M hexamethylenetetramine under a 3 W / cm² ultrasonic field (40 kHz);

[0076] Step 3: placing the desized basalt fiber fabric in the seed solution for 30 minutes, filtering at room temperature, and then curing in an oven at 150° C. for 60 minutes to obtain a fiber fabric with a seed layer;

[0077] Step 4: placing the fiber fabric with the seed layer in a growth solution, turning on a 40 kHz, 3 W / cm² ultrasonic field, ultrasonically reacting at 65°C for 20 minutes, washing at room temperature, and drying at 80°C for 6 hours to obtain a ZnO-loaded fiber fabric;

[0078] Step 5: Hot-press the ZnO-loaded fiber fabric and the PLA film into 7 layers staggered at 45 degrees, and then perform graded pressurization after stacking, and cure at 110-150°C to obtain a composite material, wherein the graded pressurization specifically includes pressurizing at 180°C at 10 bar, 20 bar, 30 bar, and 40 bar, and each pressurization time is 10 minutes. Example 8

[0079] The composite materials prepared in Examples 1-7 were tested for flexural strength and interlaminar shear strength according to the B / T1449 and JC / T773 standards. Tensile properties of the composite materials prepared in Examples 1-7 were tested using a universal testing machine. The test results are shown in Table 1.

[0080] Table 1 Bending strength / MPa Interlaminar shear strength / MPa Tensile strength / MPa Example 1 300 20 280 Example 2 260 17 240 Example 3 250 16 230 Example 4 150 10 140 Example 5 270 18.5 250 Example 6 275 19 275 Example 7 240 15 275

[0081] Through Table 1, Figure 1-4 It can be seen that the composite material prepared in Example 1 has good bending strength, interlaminar shear strength and tensile strength under the preparation method of the present invention. The SEM image of the composite material prepared in Example 1 obtained under a scanning electron microscope is as follows Figure 1 As shown by Figure 1The fiber surface prepared in Example 1 exhibits a distinct layered fiber orientation and uniform ZnO nanorod coverage. (a) The PDA-modified basalt fiber fabric exhibits a smooth and regularly arranged surface, extending along the fiber orientation throughout the entire field of view, with no visible cracks or delamination. (b) Under high magnification, the ZnO nanorods exhibit orderly, oriented growth perpendicular to the fiber surface. The nanorods are approximately 1–2 μm in length and 80–120 nm in diameter, densely distributed, and exhibit no apparent agglomeration. A magnified image further reveals that each nanorod has sharp tips and smooth sidewalls, and is tightly bonded to the PDA interlayer, exhibiting no signs of detachment or breakage. The overall interfacial transition zone is dense, with no visible voids or micropores. This demonstrates that the ultrasound-assisted low-temperature hydrothermal growth combined with the graded hot pressing process effectively achieves deep interlocking and uniform infiltration of the nanoreinforcement phase with the fiber and PLA matrix, facilitating load transfer and crack deflection, thereby significantly improving flexural strength, interlaminar shear strength, and tensile strength.

[0082] Compared with Example 1, the composite material prepared in Example 2 was composed of 7 layers of ZnO-loaded fiber fabric and PLA film heat-pressed and stacked at 0 degrees. The composite material prepared in Example 3 was composed of 7 layers of ZnO-loaded fiber fabric and PLA film heat-pressed and stacked at 90 degrees. Example 1 was stacked at 45 degrees. The interlaminar shear strength of Examples 2 and 3 was worse than that of Example 1. Moreover, compared with Examples 2 and 3, the stress dispersion efficiency of Examples 2 and 3 was lower. In the 0° ply, the fiber orientation of each layer was consistent, and the shear load was concentrated along the fiber direction. There was a lack of a cross-layer load dispersion mechanism, which easily formed a stress concentration area at the interface. In the 90° ply, the fiber layers were arranged orthogonally. When the load switched in different directions, multiple slip surfaces were generated, the number of interface shear surfaces increased, and it was difficult to effectively disperse the shear stress. The 0° interlaminar cracks extended linearly along the fiber direction, with almost no deflection or bridging. Energy dissipation was insufficient, and the interface was prone to failure. In 90° stacking, cracks propagate rapidly at the orthogonal interface, resulting in weak crack pinning and deflection effects, which also leads to interlayer delamination. In symmetrical stacking at 0° or 90°, the oriented structure of the ZnO nanorods and PDA layer cannot form an effective "pinning" angle with the shear direction, and the physical interlocking and chemical coordination capabilities against shear are inferior to those of 45° stacking.

[0083] Compared with Example 1, in Example 4, the ZnO-loaded fiber fabric and PLA film were hot-pressed and stacked in two layers at a 45-degree angle. However, due to the small number of stacked layers, the overall thickness and stiffness of the composite material were insufficient, and the load was concentrated on a single interface, failing to form multi-layer redundant load-bearing. Furthermore, during graded pressurization, the pressure failed to effectively penetrate the middle layer, resulting in incomplete interface infiltration in some areas, resulting in micropores and voids.

[0084] Compared with Example 1, the graded pressurization in Example 5 specifically includes pressurization at 180°C at 10 bar, 25 bar, 40 bar, and 55 bar. Unlike the 10 bar, 20 bar, 30 bar, and 40 bar in Example 1, the excessively high pressure of 55 bar in the last stage causes local excessive flow of the PLA matrix, collapse or extrusion of the nanorods and PDA layer microregions; excessive pressure can easily damage the basalt fiber body, causing micro fractures and reducing the overall strength of the composite material;

[0085] In Example 6, the thickness of each layer of ZnO-loaded fiber fabric and PLA film after curing is different from the thickness of the present invention. The uneven layer thickness of the composite material of Example 6 leads to uneven pressure distribution during graded pressurization, with overpressure in the thin layer area and underpressure in the thick layer area; insufficient interface infiltration in the underpressure area, increased voids and micropores, resulting in low local stiffness and easy interlayer delamination; the load transfer path is disordered, the local stress peak is increased, and the bending strength is reduced.

[0086] The composite material prepared in Example 7 did not produce dopamine-coated fiber fabric in the dopamine solution. The composite material prepared in Example 7 lacked a PDA intermediate adhesion layer, and the ZnO nanorod seed layer was weakly bonded to the basalt fiber surface and easily fell off. The ZnO was sparsely distributed and agglomerated, and the nano-reinforced phase could not uniformly form a network skeleton.

[0087] In summary, the composite material obtained by the preparation method of the present invention can not only achieve rapid growth and uniform high-density distribution of ZnO nanorods within 15-30 minutes, but also the obtained PLA-based (polylactic acid) composite material has excellent interlaminar shear strength, flexural strength and tensile strength.

[0088] The above descriptions are only some specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for preparing a composite material of basalt fabric and PLA film based on ZnO nanorods, characterized in that: The following steps are involved: obtaining a surface-desized basalt fiber fabric; preparing a dopamine solution, a seed solution, and a generating solution; The desized basalt fiber fabric is immersed in a dopamine suspension to obtain a dopamine-coated fiber fabric; placing the dopamine-wrapped fiber fabric in a seed solution to obtain a fiber fabric with a seed layer; The fiber fabric with the seed layer is placed in a growth solution, and the ZnO-loaded fiber fabric is grown by ultrasound-assisted growth; The ZnO-loaded fiber fabric and the PLA film are hot-pressed to obtain a composite material.

2. The method for preparing a composite material of basalt fabric and PLA film based on ZnO nanorods according to claim 1, characterized in that: The ZnO-loaded fiber fabric and PLA film were hot-pressed and stacked at a 45-degree angle. After stacking, they were subjected to graded pressurization and cured at 110-150°C to obtain a composite material.

3. The method for preparing a composite material of basalt fabric and PLA film based on ZnO nanorods according to claim 2, characterized in that: The graded pressurization specifically includes pressurization at 180° C. at 10 bar, 20 bar, 30 bar and 40 bar, and each pressurization time is not less than 10 minutes.

4. The method for preparing a composite material of basalt fabric and PLA film based on ZnO nanorods according to claim 1, characterized in that: The ZnO-loaded fiber fabric and PLA film were hot-pressed and stacked at least 7 layers at a 45-degree angle.

5. The method for preparing a composite material of basalt fabric and PLA film based on ZnO nanorods according to claim 1, characterized in that: The process of obtaining a surface-desized basalt fiber fabric comprises the following steps: The basalt fiber fabric was placed in an air atmosphere tube furnace, heated to 500°C and kept warm, and then cooled to room temperature to complete high-temperature desizing. The basalt fiber fabric after high-temperature desizing is immersed in an acetone-isopropyl alcohol mixed solution for ultrasonic vibration, and then dried after vibration to obtain the basalt fiber fabric with surface desizing.

6. The method for preparing a composite material of basalt fabric and PLA film based on ZnO nanorods according to claim 1, characterized in that: The dopamine-wrapped fiber fabric was placed in the seed solution, filtered at room temperature, and then cured in an oven at 150°C for 60 min to obtain a fiber fabric with a seed layer.

7. The method for preparing a composite material of basalt fabric and PLA film based on ZnO nanorods according to claim 6, characterized in that: The seed solution includes zinc acetate, sodium lauryl sulfate, and NaOH.

8. The method for preparing a composite material of basalt fabric and PLA film based on ZnO nanorods according to claim 6, characterized in that: The fiber fabric with the seed layer is placed in a growth solution, an ultrasonic field is turned on, and the reaction is carried out at 55-80° C. for 15-30 minutes. After the reaction, the fiber fabric is washed at room temperature and dried at 80° C. for 6 hours to obtain a ZnO-loaded fiber fabric.

9. The method for preparing a composite material of basalt fabric and PLA film based on ZnO nanorods according to claim 8, characterized in that: The growth solution included an ethanol-water mixture, zinc nitrate, and hexamethylenetetramine.

10. A composite material prepared according to the preparation method according to any one of claims 1 to 9.

Images