Basalt fiber plate with waterproof and high interlayer toughness and preparation method thereof

Abstract

The application relates to the field of fiber reinforced composite materials, and particularly discloses a basalt fiber plate with waterproofness and high interlaminar toughness and a preparation method thereof. The basalt fiber plate with waterproofness and high interlaminar toughness comprises an upper surface layer, a middle layer and a lower surface layer from top to bottom, the upper surface layer and the lower surface layer are basalt fiber fabrics, the middle layer is a plurality of layers of resin pre-impregnated basalt fiber unidirectional cloth, the resin pre-impregnated basalt fiber unidirectional cloth is prepared by impregnating a resin solution into a basalt fiber unidirectional cloth matrix, and the laying angles of the plurality of layers of resin pre-impregnated basalt fiber unidirectional cloth are +45 DEG and 90 DEG. The laminated plate material is used for a UAV arm, and has the advantages of strong interface adhesion, waterproofness, anti-permeability, tensile resistance and impact resistance.

Description

Technical Field

[0001] This application relates to the field of fiber-reinforced composite materials technology, and more specifically, to a basalt fiberboard with both waterproof and interlayer toughness and its preparation method. Background Technology

[0002] Fiber-reinforced resin matrix composites have found wide application in aerospace, rail transportation, wind power, and high-end protective equipment due to their excellent lightweight and high strength properties. Currently, high-performance fiber-reinforced thermosetting resin matrix composites are mainly based on carbon fiber / epoxy resin systems. Taking T300 grade carbon fiber unidirectional sheets as an example, they are mainly used in lightweight aerospace structural components, rail transportation vehicle body skins, wind turbine blade main beams, and high-end protective equipment shells. However, the high unit price of T300 grade carbon fiber sheets severely restricts their application in civilian drone arms and civilian high-strength protective shells.

[0003] Basalt fiber, as a novel inorganic mineral fiber, possesses excellent mechanical properties, good high-temperature resistance, acid and alkali corrosion resistance, and environmental friendliness. Furthermore, basalt fiber composites offer low manufacturing costs and good recyclability, making them an ideal alternative to carbon fiber materials for civilian applications. In recent years, basalt fiber composites have seen initial applications in UAV structural components, including fuselages, fairings, and rotor blades.

[0004] However, basalt fiber / epoxy resin composites still face key technical bottlenecks in their application. The smooth surface and chemical inertness of basalt fibers result in poor adhesion and wettability with epoxy resin when used as reinforcement in resin-based composites, leading to insufficient interfacial bonding strength between the fiber and the matrix. This makes the interfacial region prone to becoming a weak point under external forces, hindering effective stress transfer between the fiber and the matrix and limiting the full realization of the composite's overall mechanical properties.

[0005] In response to the aforementioned technologies, there is an urgent need for a basalt fiber laminate that can synergistically improve the mechanical strength and interfacial adhesion of composite materials to meet the usage requirements of civilian drone arms. Summary of the Invention

[0006] To improve the mechanical properties and interfacial adhesion of basalt fiber composite materials, this application provides a basalt fiber board with both waterproof and interlayer toughness and its preparation method.

[0007] In the first aspect, this application provides a basalt fiberboard that combines waterproofing and inter-layer toughness, employing the following technical solution: A basalt fiber board that combines waterproofing and high-rise toughness consists of an upper surface layer, a middle layer, and a lower surface layer from top to bottom. The upper and lower surface layers are made of basalt fiber fabric, and the middle layer is made of several layers of resin-preimpregnated basalt fiber unidirectional fabric. The resin-preimpregnated basalt fiber unidirectional fabric is made by impregnating a basalt fiber unidirectional fabric matrix with resin liquid. The laying angles of the resin-preimpeded basalt fiber unidirectional fabrics are ±45° and 90°.

[0008] By adopting the above technical solution, basalt fiber fabric is used as the surface layer, and resin-preimpeded basalt fiber unidirectional fabric is used as the middle layer. The middle layer has multiple layers. The unidirectional basalt fiber fabric composite material has the best tensile properties and can effectively bear the main bending moment and tension of the UAV arm as the main load-bearing layer. The plain weave fabric on the surface layer has more interlacing points and a more stable structure, which can provide better impact resistance, tear resistance and surface abrasion resistance.

[0009] Preferably, the basalt fiber unidirectional fabric matrix comprises basalt fiber unidirectional fabric and polyarylether sulfone ketone fiber membranes located on both sides of the basalt fiber unidirectional fabric; The polyarylether sulfone ketone fiber membrane is a coaxial spun fiber membrane with polyarylether sulfone ketone as the core and polyvinylidene fluoride as the shell.

[0010] By adopting the above technical solution, the porous polyarylether sulfone ketone (PPESK) fiber membrane on both sides of the basalt fiber unidirectional fabric can increase the resin penetration during resin impregnation through capillary effect, allowing for thorough wetting of each monofilament, improving the interfacial bonding between the fiber and resin. Furthermore, it can slow down the macroscopic flow rate of the resin, resulting in smoother and more stable resin penetration, avoiding defects such as bubbles and dry spots, and obtaining a more uniform laminate. During the hot-pressing process for preparing laminated sheets, the polyvinylidene fluoride (PVDF) shell melts and softens, undergoing intense molecular chain movement. This results in adhesion points forming at the intersections of the polyarylether sulfone ketone (PAF) / PVDF fibers, creating a strong bond with the basalt fiber unidirectional fabric. The bonded area is large, and the interfacial adhesion is excellent, preventing interfacial delamination and separation. Furthermore, the PVDF shell melts after hot pressing, acting as a compatibilizer between the fiber membrane and the resin solution. This makes the fiber membrane easier to wet with the resin, forming a tighter interface with fewer defects between the fiber membrane and the basalt fiber unidirectional fabric, resulting in a strong interfacial bond and enhanced anti-delamination ability. Polyarylethersulfone ketone fiber, serving as the core layer, exhibits excellent thermal stability. During hot pressing to prepare the sheet, the melted and softened shell layer is bonded to the surface of the basalt fiber unidirectional cloth. The overlapping fibers provide a high-strength skeleton, effectively bearing loads in the composite material, increasing the toughness of the composite material, and hindering crack propagation. The melt bonding of the shell layer after hot pressing can enhance the integrity of the fiber membrane, improve the mechanical strength of the fiber membrane, and improve the impact resistance and tensile properties of the composite material.

[0011] Preferably, the raw materials of the resin liquid include the following parts by weight: 100 parts epoxy resin, 8-10 parts curing agent, 30-35 parts polyurethane, 3-5 parts nano zirconium oxide, 1-2 parts toughening agent and 5-10 parts flame retardant.

[0012] By adopting the above technical solution, polyurethane toughened epoxy resin is used when pre-impregnating the basalt fiber unidirectional fabric matrix. The two form an interpenetrating network structure. The flexible segments of polyurethane can fill the micro-cracks generated during epoxy resin curing, improve the impact strength, tensile strength and shear strength of epoxy resin, enhance toughness, effectively block water molecule penetration, reduce water absorption rate, improve impermeability, and improve the bond strength loss rate after long-term water immersion, making the composite material more durable in humid environments. After impregnating the basalt fiber unidirectional fabric matrix with an appropriate amount of nano-zirconia in the resin liquid, it can be enriched on the surface of the polyarylether sulfone ketone fiber membrane, enhancing its mechanical locking force and chemical bonding with epoxy resin, making the two more tightly bonded, enhancing interfacial adhesion performance, thereby improving mechanical properties and corrosion resistance.

[0013] Preferably, the nano-zirconia is pre-treated with hydroxyl-terminated polydimethylsiloxane for hydrophobic modification.

[0014] By adopting the above technical solution, the hydroxyl groups at the end of hydroxyl-terminated polydimethylsiloxane can form hydrogen bonds with the surface of nano-zirconia or epoxy resin. Its flexible siloxane backbone can effectively toughen the resin and give zirconia excellent hydrophobicity, improve the dispersibility of zirconia in resin liquid, thereby improving interfacial adhesion performance, enhancing mechanical properties, improving water molecule penetration resistance and corrosion resistance, and extending the service life of the material in harsh environments.

[0015] Preferably, the thickness of the polyarylether sulfone ketone fiber membrane is 30-50 μm.

[0016] By adopting the above technical solution, in fiber membranes of the above thickness, the PVDF shell undergoes micro-thermal melting during hot pressing, enhancing the adhesion between fibers and improving the interfacial interaction with the unidirectional fabric. While achieving the same toughening effect, it reduces the negative impact on wetting, balancing the wetting and toughening effects. The polyarylether sulfone ketone core layer exhibits excellent thermal stability, increasing interlaminar fracture toughness and improving the tensile strength and other mechanical properties of the composite material. If the fiber membrane thickness is too low, the toughening effect is limited; if it is too thick, the resin solution cannot completely wet the membrane, leading to a decrease in performance.

[0017] Preferably, a waterproof fiber membrane is disposed on the side of the upper and lower surface layers near the middle layer. The waterproof fiber membrane is prepared by electrospinning on the surface of the upper and lower surface layers using a spinning solution containing PVDF, TPU and boron nitride nanosheets. The mass ratio of PVDF, TPU and boron nitride nanosheets in the spinning solution is 1:0.4-0.6:0.1-0.15.

[0018] By employing the above technical solution, basalt fiber fabric is used as the outer layer to resist external wear and impact, protecting the inner waterproof fiber membrane and preventing it from being directly exposed to the outside, thus preventing damage due to friction or scratches and ensuring the durability of the waterproof function. Furthermore, the waterproof fiber membrane, located between the surface and intermediate layers, acts as an interlayer intercalator, effectively improving the interlayer fracture toughness of the laminate and resisting delamination. In addition, the waterproof fiber membrane is formed on the upper and lower surface layers through electrospinning, creating a high-porosity, interconnected three-dimensional network structure, thereby achieving a highly efficient waterproof effect.

[0019] Both PVDF and TPU are excellent waterproof materials. The waterproof fiber membrane has a microporous structure that can effectively block liquid water and provide excellent waterproof performance. Moreover, the addition of TPU improves the flexibility and elasticity of the waterproof fiber membrane, improves the toughness of the composite material, and prevents deformation or cracking under stress. Boron nitride nanosheets have a high thermal conductivity. In the waterproof fiber membrane, a three-dimensional thermal conductive network is constructed, which helps to quickly dissipate the heat generated by the drone arm during flight or high-intensity maneuvering, avoiding local overheating. Furthermore, boron nitride nanosheets can further improve the surface roughness and hydrophobicity of the waterproof fiber membrane, further enhancing its waterproof performance.

[0020] Preferably, the thickness of the waterproof fiber membrane is 20-100 μm.

[0021] By adopting the above technical solutions, the higher the thickness of the waterproof fiber membrane, the better the waterproof performance; however, the increase in thickness will also affect the flexibility of the material.

[0022] Preferably, the curing agent is selected from at least one of methyltetrahydrophthalic anhydride, 1,2-dimethylimidazole, and aromatic amines; The flame retardant is selected from at least one of bisphenol A bis(diphenyl phosphate), magnesium hydroxide, decabromodiphenyl ether, red phosphorus and melamine derivatives; The toughening agent is selected from silicone elastomers and / or polyacrylate elastomers.

[0023] Secondly, this application provides a method for preparing basalt fiberboard that combines waterproofing and interlayer toughness, employing the following technical solution: A method for preparing basalt fiberboard with both waterproof and interlayer toughness includes the following steps: Basalt fibers are heat-treated and then cooled to room temperature, then woven to produce basalt fiber plain weave fabric and basalt fiber unidirectional fabric, respectively. Epoxy resin, polyurethane, nano-zirconia, toughening agent and flame retardant are mixed evenly, curing agent is added, and after stirring evenly, toluene / acetone solvent is added and stirred evenly to obtain resin liquid. Polyarylethersulfone ketone fiber membranes were laid on both sides of basalt fiber unidirectional fabric to obtain basalt fiber unidirectional fabric matrix; The basalt fiber unidirectional fabric matrix is ​​impregnated in resin liquid and semi-cured at 100-120℃ for 1-2 hours to obtain resin pre-impregnated basalt fiber unidirectional fabric. Place a basalt fiber plain weave fabric as the lower surface layer in the mold. Lay several layers of resin-preimpeded basalt fiber unidirectional fabric as the middle layer on the basalt fiber plain weave fabric. Then lay another basalt fiber plain weave fabric as the upper surface layer on the middle layer. Press at 90-100℃ and 1-8MPa for 2 hours. Raise the temperature to 120-140℃ and press at 1-5MPa for 1-2 hours. Hold at 160-180℃ under normal pressure for 1-2 hours.

[0024] By adopting the above technical solution, basalt fibers are first heat-treated to remove the sizing agent, impurities and moisture from the fiber surface, causing slight oxidation on the basalt fiber surface, increasing surface active groups, which helps to improve the interfacial bonding force between the fiber and the resin matrix; then they are woven into plain weave fabric and unidirectional fabric. The plain weave fabric serves as the upper and lower surface layers, providing surface abrasion resistance, while the unidirectional fabric has high strength and modulus, serving as the middle layer to bear the load.

[0025] The basalt fiber unidirectional fabric matrix is ​​impregnated in resin solution to fully wet the unidirectional fabric and fiber membrane. Then, it is semi-cured to make the resin reach a partially cross-linked viscous state, which facilitates subsequent lay-up operations and prevents excessive resin loss during pressing.

[0026] The layers are laid in a mold according to a top-middle-bottom structure. First, the resin is allowed to flow and impregnate fully at a low temperature and low viscosity, and air bubbles and volatiles are removed to ensure the density of the finished product. At the same time, the PVDF shell in the polyarylethermonone sulfone ketone fiber undergoes micro-thermal melting, bonding the fiber membrane to the unidirectional fabric and adjacent fibers to form a tighter fiber network structure. This hot-pressing treatment can improve the tensile strength of the fiber membrane and enhance its overall strength. The micro-melted PVDF not only bonds the fibers but also impregnates and anchors the surrounding epoxy resin matrix, increasing the bonding force between the fiber membrane and the upper and lower resin layers. At the same time, the micro-melting maintains a three-dimensional porous structure and retains a high porosity after hot pressing, ensuring that the resin fully impregnates the fiber membrane. Next, the temperature is increased to cross-link and cure the epoxy resin, forming a cross-linked network. Finally, high-temperature treatment at normal pressure allows the resin to reach a high degree of curing, perfecting the cross-linked network and improving the material's heat resistance, dimensional stability, and long-term performance.

[0027] Preferably, the thickness of the laminate is 1.5-100mm.

[0028] In summary, this application has the following beneficial effects: 1. Because this application uses polyarylethersulfone ketone (PASSF) fiber membranes made of PASSF and polyvinylidene fluoride (PVDF) on both sides of the basalt fiber unidirectional fabric, the fiber membranes have high porosity, which is beneficial for the penetration of resin liquid during impregnation. Because PVDF can not only bond the fibers through micro-thermal melting during hot pressing, it can also wet the surrounding resin matrix to form a strong mechanical interlocking structure, which greatly enhances the interfacial bonding strength between the fiber membrane and the resin, improves interfacial compatibility, improves interlayer peel strength, and avoids interfacial defects that may occur when PASSF directly contacts the resin. The PASSF core layer with excellent thermal stability does not soften during hot pressing, and can provide solid mechanical support, thus improving the mechanical strength of the composite material.

[0029] 2. In this application, a waterproof fiber membrane is preferably formed on the inner side of the surface by electrospinning. PVDF provides a mechanical skeleton and hydrophobicity, TPU gives the spun fibers flexibility, and boron nitride nanosheets provide high thermal conductivity. The three complement each other, taking into account protection, toughening and waterproofing. Attached Figure Description

[0030] Figure 1 This is a cross-sectional view of the laminated board prepared in Example 1 of this application. Detailed Implementation

[0031] The present application will be further described in detail below with reference to the embodiments.

[0032] Preparation example of polyarylethersulfone ketone

[0033] Preparation Example I: Weigh 8 mmol DBD (4,4'-diphenyl-diazinaphthone), 2 mmol DHPZ (4-(4-hydroxyphenyl)-2,3-diazanaphth-1-one), 7 mmol DFS (4,4'-difluorodiphenyl sulfone), 3 mmol DFK (4,4'-difluorodibenzophenone), and 14 mmol potassium carbonate. Mix these with 7.5 mL sulfolane solvent and toluene dehydrating agent. Stir and heat to 140 °C under nitrogen protection. After reflux to remove water for 3 h, remove toluene. Gradually increase the temperature to 195 °C and polymerize for 8 h. Precipitate the product in 400 mL of hot water with a small amount of hydrochloric acid added to obtain a crude product. Dissolve the crude product in NMP, filter, and precipitate in 400 mL of ethanol. Dry to obtain polyarylether sulfone ketone (PPESK).

[0034] Preparation Example 1: Polyarylene ether sulfone ketone prepared by the method in Preparation Example 1 was dissolved in an NMP / THF (v / v, 1 / 1) mixture and stirred at 40°C for 12 h to obtain a solution A with a concentration of 20 wt%. Polyvinylidene fluoride (PVDF) was dissolved in a DMAC / acetone (v / v, 7 / 3) mixture and stirred at 40°C for 12 h to obtain a solution B with a concentration of 16 wt%. The PVDF was selected from Dongguan Zhongzhite and its brand name was Solvay 761A. Solutions A and B were connected to a stainless steel needle with a coaxial device for coaxial electrospinning. The fiber membrane was vacuum dried at 80°C for 48 h to remove residual solvent from the fiber. The processing parameters for coaxial electrospinning were as follows: applied voltage of 13 kV, receiving distance of 20 cm, injection speed of outer layer solution B of 0.12 mm / min, injection speed of inner layer solution A of 0.08 mm / min, and fiber collection time was adjusted according to the required thickness to obtain a polyarylene ether sulfone ketone fiber membrane.

[0035] Preparation Example 2: Polyarylene ether sulfone ketone prepared by the method in Preparation Example 1 was dissolved in an NMP / THF (v / v, 1 / 1) mixture and stirred at 40°C for 12 h to obtain a spinning solution with a concentration of 20 wt%. Then, electrospinning was performed, and the solution was dried at 120°C for 24 h to allow the solvent to fully evaporate. The spinning voltage was 13 kV, the receiving distance was 20 cm, the injection speed was 0.12 mm / min, and the spinning time was adjusted to obtain a polyarylene ether sulfone ketone fiber membrane. Example

[0036] In the following examples and comparative examples, the epoxy resin was selected from Baling Petrochemical, model E-51; the polyurethane in the resin solution was selected from Yantai Wanhua, model WHT-8285; the polyacrylate elastomer was selected from Shandong Sanshi, model SS-N39; the nano-zirconia was selected from Tianxing New Materials, with a particle size of 30nm; the PVDF was selected from Dongguan Zhongzhite, brand Solvay 761A; the TPU in the spinning solution was selected from BASF, model 1190A; and the boron nitride nanosheets were selected from Beijing Deco Island, with a specific surface area of ​​30m².2 / g, hydroxyl-terminated polydimethylsiloxane is selected from Shanghai Maclean Reagent, model number 768077, viscosity is 65cSt.

[0037] Example 1: A basalt fiberboard with both waterproof and high-rise interlayer toughness, consisting of an upper surface layer, a middle layer and a lower surface layer from top to bottom. The upper and lower surface layers are plain basalt fiber fabrics, and the middle layer is composed of several layers of resin-preimpeded basalt fiber unidirectional fabric. The interlayer arrangement of adjacent resin-preimpeded basalt fiber unidirectional fabrics is 0° / +45° / -45° / 90°.

[0038] The resin-preimpregnated basalt fiber unidirectional fabric is made by impregnating a basalt fiber unidirectional fabric matrix with resin liquid. The basalt fiber unidirectional fabric matrix is ​​basalt fiber unidirectional fabric.

[0039] The resin liquid contains the following raw materials in parts by weight: 100g epoxy resin, 10g curing agent methyltetrahydrophthalic anhydride, 35g polyurethane, 3g nano zirconium oxide, 2g toughening agent polyacrylate elastomer, and 10g flame retardant bisphenol A bis(diphenyl phosphate).

[0040] The method for preparing the above-mentioned basalt fiber laminate includes the following steps: S1. Basalt fibers are heat-treated at 40℃ for 30 minutes, cooled to room temperature, and woven to obtain basalt fiber plain weave fabric and basalt fiber unidirectional fabric respectively. S2. Mix epoxy resin, polyurethane, nano zirconia, toughening agent and flame retardant evenly, add curing agent, stir evenly, add toluene / acetone (v / v, 1 / 1) solvent, adjust the amount of solvent added to make the solid content 40wt%, stir evenly to obtain resin liquid. S3. Using basalt fiber unidirectional fabric as the basalt fiber unidirectional fabric matrix, impregnate it in resin liquid for 5 minutes to allow the resin liquid to fully impregnate the unidirectional fabric matrix, and then semi-cur it at 100℃ for 1 hour to obtain resin pre-impregnated basalt fiber unidirectional fabric. S4. Place a basalt fiber plain weave fabric as the lower surface layer in the mold. Lay several layers of resin-preimpeded basalt unidirectional fabric as the intermediate layer on the basalt fiber plain weave fabric. Lay a basalt fiber plain weave fabric as the upper surface layer on the intermediate layer. See Table 1 for the specific layering method. Heat to 100℃ at a rate of 2℃ / min and press at 5MPa for 2 hours. Then heat to 120℃ at 2℃ / min and press at 2MPa for 1 hour. After depressurization to normal pressure, heat to 160℃ at 2℃ / min and hold for 1 hour to obtain a laminated board with a thickness of 8.102mm.

[0041] Table 1 Layup method of resin-preimpregnated basalt fiber unidirectional fabric in the intermediate layer

[0042] Example 2: A basalt fiberboard with both waterproof and high-rise interlayer toughness, consisting of an upper surface layer, a middle layer and a lower surface layer from top to bottom. The upper and lower surface layers are plain basalt fiber fabrics, and the middle layer is composed of several layers of resin-preimpeded basalt fiber unidirectional fabric. The interlayer arrangement of adjacent resin-preimpeded basalt fiber unidirectional fabrics is 0° / +45° / -45° / 90°.

[0043] The resin-preimpregnated basalt fiber unidirectional fabric is made by impregnating a basalt fiber unidirectional fabric matrix with resin liquid. The basalt fiber unidirectional fabric matrix includes basalt fiber unidirectional fabric and polyarylether sulfone ketone fibers located on both sides of the basalt fiber unidirectional fabric. The polyarylether sulfone ketone fibers are coaxially spun fiber membranes with polyarylether sulfone ketone as the core and polyvinylidene fluoride as the shell. It was made by Preparation Example 1, and the spinning time in Preparation Example 1 was adjusted so that the thickness of the polyarylether sulfone ketone fiber membrane was 50 μm.

[0044] The resin liquid contains the following raw materials in parts by weight: 100g epoxy resin, 10g curing agent methyltetrahydrophthalic anhydride, 35g polyurethane, 3g nano zirconium oxide, 2g toughening agent polyacrylate elastomer, and 10g flame retardant bisphenol A bis(diphenyl phosphate).

[0045] The preparation method of the above-mentioned basalt fiberboard with both waterproof and inter-layer toughness includes the following steps: S1. Basalt fibers are heat-treated at 40℃ for 30 minutes, cooled to room temperature, and woven to obtain basalt fiber plain weave fabric and basalt fiber unidirectional fabric respectively. S2. Mix epoxy resin, polyurethane, nano zirconia, toughening agent and flame retardant evenly, add curing agent, stir evenly, add toluene / acetone (v / v, 1 / 1) solvent, adjust the amount of solvent added to make the solid content 40wt%, stir evenly to obtain resin liquid. S3. Lay the polyarylether sulfone ketone fiber membrane on both sides of the basalt fiber unidirectional fabric to obtain the basalt fiber unidirectional fabric matrix. S4. The basalt fiber unidirectional fabric matrix is ​​immersed in resin solution for 5 minutes to fully impregnate the unidirectional fabric matrix with resin solution, and then semi-cured at 100℃ for 1 hour to obtain resin pre-impregnated basalt fiber unidirectional fabric. S5. Place a basalt fiber plain weave fabric as the lower surface layer in the mold. Lay several layers of resin-preimpeded basalt fiber unidirectional fabric as the middle layer on the basalt fiber plain weave fabric. Then lay a basalt fiber plain weave fabric as the upper surface layer on the middle layer. The specific layering direction is shown in Table 1. Heat the fabric to 100℃ at a rate of 2℃ / min and press it at 5MPa for 2 hours. Then heat the fabric to 120℃ at a rate of 2℃ / min and press it at 2MPa for 1 hour. After depressurizing to normal pressure, heat the fabric to 160℃ at a rate of 2℃ / min and keep it at that temperature for 1 hour to obtain the laminated board.

[0046] Example 3: A basalt fiberboard with both waterproof and high-rise interlayer toughness, consisting of an upper surface layer, a middle layer and a lower surface layer from top to bottom. The upper and lower surface layers are plain basalt fiber fabrics, and the middle layer is composed of several layers of resin-preimpeded basalt fiber unidirectional fabric. The interlayer arrangement of adjacent resin-preimpeded basalt fiber unidirectional fabrics is 0° / +45° / -45° / 90°.

[0047] The resin-preimpregnated basalt fiber unidirectional fabric is made by impregnating a basalt fiber unidirectional fabric matrix with resin liquid. The basalt fiber unidirectional fabric matrix includes basalt fiber unidirectional fabric and polyarylether sulfone ketone fibers located on both sides of the basalt fiber unidirectional fabric. The polyarylether sulfone ketone fibers are coaxially spun fiber membranes with polyarylether sulfone ketone as the core and polyvinylidene fluoride as the shell. It was made by Preparation Example 1, and the spinning time in Preparation Example 1 was adjusted so that the thickness of the polyarylether sulfone ketone fiber membrane was 50 μm.

[0048] The resin liquid contains the following raw materials in parts by weight: 100g epoxy resin, 8g curing agent methyltetrahydrophthalic anhydride, 30g polyurethane, 5g nano zirconium oxide, 1g toughening agent polyacrylate elastomer, and 5g flame retardant bisphenol A bis(diphenyl phosphate).

[0049] The preparation method of the above-mentioned basalt fiberboard with both waterproof and inter-layer toughness includes the following steps: S1. Basalt fibers are heat-treated at 40℃ for 30 minutes, cooled to room temperature, and woven to obtain basalt fiber plain weave fabric and basalt fiber unidirectional fabric respectively. S2. Mix epoxy resin, polyurethane, nano zirconia, toughening agent and flame retardant evenly, add curing agent, stir evenly, add toluene / acetone (v / v, 1 / 1) solvent, adjust the amount of solvent added to make the solid content 50wt%, stir evenly to obtain resin liquid. S3. Lay the polyarylether sulfone ketone fiber membrane on both sides of the basalt fiber unidirectional fabric to obtain the basalt fiber unidirectional fabric matrix. S4. The basalt fiber unidirectional fabric matrix is ​​immersed in resin solution for 5 minutes to fully impregnate the unidirectional fabric matrix with resin solution, and then semi-cured at 120℃ for 1 hour to obtain resin pre-impregnated basalt fiber unidirectional fabric. S5. Place a basalt fiber plain weave fabric as the lower surface layer in the mold. Lay several layers of resin-preimpeded basalt fiber unidirectional fabric as the middle layer on the basalt fiber plain weave fabric. Then lay a basalt fiber plain weave fabric as the upper surface layer on the middle layer. The specific layering method is shown in Table 1. Heat the fabric to 120°C at a rate of 2°C / min and press it at 2MPa for 2 hours. Then heat the fabric to 140°C at a rate of 2°C / min and press it at 1MPa for 1 hour. After depressurizing to normal pressure, heat the fabric to 180°C at a rate of 2°C / min and keep it at that temperature for 1 hour to obtain a laminated board with a thickness of 7mm.

[0050] Example 4: A basalt fiberboard with both waterproof and high-rise interlayer toughness, which differs from Example 2 in that the thickness of the polyarylether sulfone ketone fiber membrane is 10 μm.

[0051] Example 5: A basalt fiberboard with both waterproof and high-rise interlayer toughness, which differs from Example 2 in that the thickness of the polyarylether sulfone ketone fiber membrane is 100 μm.

[0052] Example 6: A basalt fiberboard with both waterproof and high-rise interlayer toughness, which differs from Example 2 in that nano-zirconia is not added to the resin liquid.

[0053] Example 7: A basalt fiberboard with both waterproof and high-rise interlayer toughness, which differs from Example 2 in that no polyurethane is added to the resin liquid.

[0054] Example 8: A basalt fiberboard with both waterproof and high-rise interlayer toughness. The difference from Example 2 is that the nano-zirconia in the resin solution is pretreated by hydrophobic modification with hydroxyl-terminated polydimethylsiloxane. The specific hydrophobic modification pretreatment method is as follows: 3g of nano-zirconia is dispersed in 20mL of n-hexane, stirred for 1h, then 1g of hydroxyl-terminated polydimethylsiloxane and 0.1g of dibutyltin dilaurate are added, stirred for another 24h, centrifuged, washed with n-hexane, and dried at 80℃ for 12h.

[0055] Example 9: A basalt fiberboard with both waterproofing and interlayer toughness, differing from Example 8 in that a waterproof fiber membrane is attached to the upper and lower surface layers near the middle layer. The waterproof fiber membrane is obtained by electrospinning a spinning solution on the surfaces of the upper and lower surface layers. The spinning solution contains PVDF, TPU, and boron nitride nanosheets in a mass ratio of 1:0.6:0.15. The preparation method of this basalt fiber-containing laminate is as follows: S1. Basalt fibers are heat-treated at 40℃ for 30 minutes, cooled to room temperature, and woven to obtain basalt fiber plain weave fabric and basalt fiber unidirectional fabric respectively. S2. Mix PVDF and TPU to obtain a blend. Take 2.4g of the blend and add it to 17.6g of DMF / THF mixture (DMF / THF mass ratio is 1:1). Stir at 60℃ for 8h until completely dissolved. Add boron nitride nanosheets and stir for 10h to obtain the spinning solution. S3. Using basalt fiber plain weave fabric as the receiving substrate, electrospinning the spinning solution and vacuum drying it at 60°C to form a fiber membrane on one side of the basalt fiber plain weave fabric. The spinning voltage is 20kV, the receiving distance is 20cm, the feeding speed is 1mL / h, the roller speed is 200r / min, and the spinning time is adjusted to make the thickness of the waterproof fiber membrane 50μm. S4. Mix epoxy resin, polyurethane, nano zirconia, toughening agent and flame retardant evenly, add curing agent, stir evenly, add toluene / acetone (v / v, 1 / 1) solvent, adjust the amount of solvent added to make the solid content 40wt%, stir evenly to obtain resin liquid. S5. Lay the polyarylether sulfone ketone fiber membrane on both sides of the basalt fiber unidirectional fabric to obtain the basalt fiber unidirectional fabric matrix. S6. The basalt fiber unidirectional fabric matrix is ​​immersed in resin liquid for 5 minutes to fully impregnate the unidirectional fabric matrix with resin liquid, and then semi-cured at 120℃ for 1 hour to obtain resin pre-impregnated basalt fiber unidirectional fabric. S7. Place a plain basalt fiber fabric with a waterproof fiber membrane on its surface as the lower layer in the mold, with the waterproof fiber membrane side facing up. Lay several layers of resin-preimpeded basalt fiber unidirectional fabric as the middle layer on the plain basalt fiber fabric. The laying method of the several layers of resin-preimpeded basalt fiber unidirectional fabric is shown in Table 1. Then lay a plain basalt fiber fabric with a waterproof fiber membrane on its surface as the upper layer on the middle layer, with the waterproof fiber membrane facing down. Heat the fabric to 120°C at a rate of 2°C / min and press it at a pressure of 2MPa for 2 hours. Then heat the fabric to 140°C at a rate of 2°C / min and press it at 1MPa for 1 hour. After depressurization, heat the fabric to 180°C at a rate of 2°C / min and keep it at that temperature for 1 hour to obtain the laminated board.

[0056] Example 10: A basalt fiberboard with both waterproof and high-rise interlayer toughness, which differs from Example 9 in that boron nitride nanosheets are not added to the raw materials of the waterproof fiber membrane on the upper and lower surfaces.

[0057] Example 11: A basalt fiberboard with both waterproof and high-rise interlayer toughness. The difference from Example 9 is that the waterproof fiber membrane is replaced by a waterproof coating membrane. The waterproof coating membrane is made by coating one side of a basalt fiber plain weave fabric with a waterproof coating liquid and then drying it at 80°C. The preparation method of the waterproof coating liquid is as follows: 2.4g of a blend (containing PVDF and TPU in a mass ratio of 1:0.6) is added to 17.6g of a DMF / THF mixture (DMF / THF mass ratio of 1:1), and stirred at 60°C for 8 hours until completely dissolved. Boron nitride nanosheets are added and stirred for 10 hours to obtain the waterproof coating liquid. The mass ratio of PVDF to boron nitride nanosheets is 1:0.15.

[0058] Comparative Example Comparative Example 1: A basalt fiberboard with both waterproof and high-rise interlayer toughness, comprising, from top to bottom, an upper surface layer, a middle layer, and a lower surface layer. The upper and lower surface layers are plain-weave basalt fiber fabrics, and the middle layer consists of several layers of resin-preimpeded basalt fiber unidirectional fabric, with adjacent layers arranged at 0° / +45° / -45° / 90°. The basalt fiber plain-weave fabrics used for the surface and lower surface layers have a basis weight of 300 g / m². 2 The thickness of the intermediate layer, which consists of several layers of resin-preimpeded basalt fiber unidirectional cloth, is 10 mm.

[0059] Resin-preimpregnated basalt fiber unidirectional fabric is made by impregnating basalt fiber unidirectional fabric with resin solution. The basis weight of the basalt fiber unidirectional fabric is 200 g / m². 2 The resin liquid contains the following raw materials in parts by weight: 100g epoxy resin, 10g curing agent methyltetrahydrophthalic anhydride, 2g toughening agent polyacrylate elastomer, and 10g flame retardant bisphenol A bis(diphenyl phosphate).

[0060] The preparation method of the above-mentioned basalt fiberboard with both waterproof and inter-layer toughness includes the following steps: S1. Basalt fibers are heat-treated at 40℃ for 30 minutes, cooled to room temperature, and woven to obtain basalt fiber plain weave fabric and basalt fiber unidirectional fabric respectively. S2. Mix epoxy resin, toughening agent and flame retardant evenly, add curing agent, stir evenly, add toluene / acetone (v / v, 1 / 1) solvent, adjust the amount of solvent added to make the solid content 40wt%, stir evenly to obtain resin liquid. S3. Immerse the basalt fiber unidirectional fabric in the resin solution for 5 minutes to allow the resin solution to fully impregnate the unidirectional fabric matrix, and then semi-cur it at 100°C for 1 hour to obtain the resin pre-impregnated basalt fiber unidirectional fabric. S4. Place a basalt fiber plain weave fabric as the lower surface layer in the mold. Lay several layers of resin-preimpeded basalt fiber unidirectional fabric as the middle layer on the basalt fiber plain weave fabric. The layup method of the resin-preimpeded basalt fiber unidirectional fabric is shown in Table 1. Then lay a basalt fiber plain weave fabric as the upper surface layer on the middle layer. Heat to 100℃ at a rate of 2℃ / min and press at 5MPa for 2 hours. Then heat to 120℃ at 2℃ / min and press at 2MPa for 1 hour. After depressurization, heat to 160℃ at 2℃ / min and keep warm for 1 hour to obtain the laminated board.

[0061] Comparative Example 2: A basalt fiber board with both waterproof and high-rise interlayer toughness, which differs from Example 1 in that the polyarylether sulfone ketone fiber membranes on both sides of the basalt fiber unidirectional fabric are made from Preparation Example 2.

[0062] Performance testing Laminated sheets were prepared according to the methods in the examples and comparative examples, and their performance was tested according to the following methods. The test results are recorded in Table 2.

[0063] 1. The tensile properties were tested in accordance with the provisions of GB1447-2005 "Test Method for Tensile Properties of Fiber Reinforced Plastics"; 2. The bending strength test shall be conducted in accordance with the provisions of GB1449-2005 "Test Method for Bending Properties of Fiber Reinforced Plastics"; 3. Interlaminar shear strength: Tested in accordance with GB / T1450.1-2005 "Test Method for Interlaminar Shear Strength of Fiber Reinforced Plastics".

[0064] 4. Water absorption rate: Refer to GB / T1462-2005 "Test method for water absorption of fiber reinforced plastics", prepare a 50mm×4mm sample with a smooth surface, immerse it in distilled water at 23℃ for 28h, take it out, wipe the surface dry, measure and record the mass change before and after immersion, and calculate the water absorption rate.

[0065] 5. Interlaminar shear strength reduction rate: Immerse a 50mm×4mm sample in distilled water at 23℃ for 960h, test its interlaminar shear strength, and calculate the interlaminar shear strength loss rate by comparing it with the initial shear strength before immersion.

[0066] Table 2

[0067] As can be seen from the data in Table 2, the laminated sheets prepared according to the methods in Examples 1-3 of this application not only have high mechanical strength, but also high interlayer shear strength, good interlayer adhesion, and excellent water resistance.

[0068] Compared with Example 2, Examples 4 and 5 respectively reduced and increased the thickness of the polyarylether sulfone ketone fiber membrane. It can be seen that the thickness of the polyarylether sulfone ketone fiber membrane located on both sides of the basalt fiber unidirectional cloth is too low, the toughening effect is limited, and the interlayer bonding strength is reduced. This indicates that a polyarylether sulfone ketone fiber membrane of appropriate thickness can improve interlayer toughness and anti-delamination ability.

[0069] Compared to Example 2, Examples 6 and 7 did not add nano-zirconia and polyurethane to the resin solution. As can be seen from the data in Table 2, the interlaminar shear strength of the laminates prepared in Examples 6 and 7 decreased, and the water absorption rate increased, resulting in poorer waterproof performance.

[0070] Compared to Example 2, Example 8 uses hydroxyl-terminated polydimethylsiloxane to perform hydrophobic pretreatment on nano-zirconia. The data in Table 2 show that the water absorption rate of the laminate prepared in Example 8 is reduced, the impermeability is enhanced, the rate of decrease in interlayer bond strength is reduced, and the mechanical strength is improved. This indicates that the hydrophobically modified zirconia can be uniformly dispersed in the resin liquid, improving the mechanical strength, interfacial adhesion, and waterproofness, so that the laminate can still work reliably in a humid environment.

[0071] Compared with Example 8, Example 9 shows that a waterproof fiber membrane is formed on the inner side of the upper and lower surface layers by electrospinning. As a result, the mechanical strength of the laminate is improved and its impermeability and waterproofness are enhanced.

[0072] Compared with Example 9, Example 10 did not add boron nitride nanosheets during electrospinning of the waterproof fiber membrane. The data in Table 2 shows that the water absorption rate of the laminate prepared in Example 10 increased, the interlaminar shear strength loss rate increased, and the mechanical properties decreased. This indicates that adding boron nitride nanosheets to the waterproof fiber membrane can improve the waterproofness of the waterproof fiber membrane and enhance the impermeability and mechanical properties of the laminate.

[0073] Compared with Example 9, Example 11, which is made by coating, does not improve the tensile strength, water absorption rate, and interlayer bonding strength of the laminate produced by coating as well as the waterproof fiber membrane formed by electrospinning.

[0074] In Comparative Example 1, no polyarylether sulfone ketone fiber membrane was used, and no polyurethane and zirconium oxide were added to the resin solution. It can be seen that the laminate made in Comparative Example 1 not only has reduced interlaminar shear strength, but also weakened waterproof and impermeable ability and deteriorated mechanical properties.

[0075] In Comparative Example 2, the polyarylether sulfone ketone fiber membrane did not contain a shell layer of PVDF and was only obtained by spinning polyarylether sulfone ketone. The interlaminar shear strength of the laminate made in Comparative Example 2 decreased and the mechanical properties were weakened.

[0076] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A basalt fiberboard board that combines waterproofing and inter-layer toughness, characterized in that, From top to bottom, the layers are an upper surface layer, a middle layer, and a lower surface layer. The upper and lower surface layers are made of basalt fiber fabric; the middle layer is made of several layers of resin-preimpregnated basalt fiber unidirectional fabric. The resin-preimpregnated basalt fiber unidirectional fabric is made by impregnating a basalt fiber unidirectional fabric matrix with a resin solution. The laying angles of the resin-preimpeded basalt fiber unidirectional fabrics are ±45° and 90°.

2. The basalt fiberboard with both waterproof and high-rise interlayer toughness according to claim 1, characterized in that: The basalt fiber unidirectional fabric matrix includes basalt fiber unidirectional fabric and polyarylether sulfone ketone fiber membrane located on both sides of the basalt fiber unidirectional fabric. The polyarylether sulfone ketone fiber membrane is a coaxial spun fiber membrane with polyarylether sulfone ketone as the core and polyvinylidene fluoride as the shell.

3. The basalt fiberboard with both waterproof and high-rise interlayer toughness according to claim 2, characterized in that: The thickness of the polyarylether sulfone ketone fiber membrane is 30-50 μm.

4. The basalt fiberboard with both waterproof and high-rise interlayer toughness according to claim 1, characterized in that: The raw materials of the resin liquid include the following parts by weight: 100 parts epoxy resin, 8-10 parts curing agent, 30-35 parts polyurethane, 3-5 parts nano zirconium oxide, 1-2 parts toughening agent and 5-10 parts flame retardant.

5. The basalt fiberboard with both waterproof and inter-layer toughness as described in claim 4, characterized in that: The nano-zirconia was pre-treated with hydroxyl-terminated polydimethylsiloxane for hydrophobic modification.

6. The basalt fiberboard with both waterproof and high-rise interlayer toughness according to claim 4, characterized in that: The curing agent is selected from at least one of methyltetrahydrophthalic anhydride, 1,2-dimethylimidazole, and aromatic amines; The flame retardant is selected from at least one of bisphenol A bis(diphenyl phosphate), magnesium hydroxide, decabromodiphenyl ether, red phosphorus and melamine derivatives; The toughening agent is selected from silicone elastomers and / or polyacrylate elastomers.

7. The basalt fiberboard with both waterproof and high-rise interlayer toughness according to claim 1, characterized in that: A waterproof fiber membrane is provided on one side of the upper and lower surfaces near the middle layer. The waterproof fiber membrane is made by electrospinning on the surfaces of the upper and lower surfaces using a spinning solution containing PVDF, TPU and boron nitride nanosheets. The mass ratio of PVDF, TPU and boron nitride nanosheets in the spinning solution is 1:0.4-0.6:0.1-0.

15.

8. The basalt fiberboard with both waterproof and high-rise interlayer toughness according to claim 7, characterized in that: The thickness of the waterproof fiber membrane is 20-100 μm.

9. The method for preparing the basalt fiberboard with both waterproof and high-rise interlayer toughness as described in any one of claims 1-8, characterized in that, Includes the following steps: Basalt fibers are heat-treated and then cooled to room temperature, then woven to produce basalt fiber plain weave fabric and basalt fiber unidirectional fabric, respectively. Epoxy resin, polyurethane, nano-zirconia, toughening agent and flame retardant are mixed evenly, curing agent is added, and after stirring evenly, toluene / acetone solvent is added and stirred evenly to obtain resin liquid. Polyarylethersulfone ketone fiber membranes were laid on both sides of basalt fiber unidirectional fabric to obtain basalt fiber unidirectional fabric matrix; The basalt fiber unidirectional fabric matrix is ​​impregnated in resin liquid and semi-cured at 100-120℃ for 1-2 hours to obtain resin pre-impregnated basalt fiber unidirectional fabric. Place a basalt fiber plain weave fabric as the lower surface layer in the mold. Lay several layers of resin-preimpeded basalt fiber unidirectional fabric as the middle layer on the basalt fiber plain weave fabric. Then lay another basalt fiber plain weave fabric as the upper surface layer on the middle layer. Press at 90-100℃ and 1-8MPa for 2 hours. Raise the temperature to 120-140℃ and press at 1-5MPa for 1-2 hours. Hold at 160-180℃ under normal pressure for 1-2 hours.

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