Basalt fiber aerogel composite material

Abstract

The invention provides a basalt fiber aerogel composite material, and relates to the field of inorganic non-metallic materials, and the basalt fiber aerogel composite material is obtained by the following steps: preparing an interface modifier; modifying the basalt fibers; 3, magnetron sputtering is carried out; and compounding the interface modified basalt fiber and the silicon dioxide aerogel. Wherein the interface modifier is obtained by mixing maleic anhydride, a long-chain diamino silane coupling agent, a silane coupling agent KH550 and a solvent composed of absolute ethyl alcohol and deionized water; the magnetron sputtering is to deposit a titanium dioxide layer on the surface of the modified basalt fiber. The basalt fiber aerogel composite material obtained through the method has the advantages of being high in interface bonding force, good in mechanical property, high in heat insulation performance, stable in long-term use performance and the like.

Description

[0001] The present invention is a divisional application of patent application number 202411028056.8, and the invention name is “A method for enhancing the interface compatibility of basalt fiber aerogel”. Technical Field

[0002] The invention relates to the technical field of inorganic non-metallic materials, and in particular to a basalt fiber aerogel composite material. Background Art

[0003] Silica aerogel is a nano-lightweight porous material with a complex three-dimensional network structure. It has the characteristics of low density, low thermal conductivity, high porosity, high light transmittance, low refractive index, and chemical stability. Its network structure is a three-dimensional polycondensate connected by silicon-oxygen bonds. It has high porosity and extremely small pore size. It is an excellent thermal insulation material that can effectively inhibit heat conduction. However, high-purity silica aerogel itself is brittle and has low mechanical strength (due to the weak strain of the silicon-oxygen covalent bond itself), which makes it easy to break and damage in actual use scenarios where it needs to bear loads. The long-term integrity of the structure and performance cannot be guaranteed. In addition, high-purity silica aerogel has poor chemical stability and is difficult to process and shape, which makes it impossible to directly apply it in the field of thermal insulation in complex environments. In the prior art, high-strength and toughness reinforcing materials are usually used to compound with silica aerogels to improve the low strength, poor toughness and poor stability of high-purity silica aerogels; however, the use of inappropriate reinforcing materials and inappropriate compounding methods not only fails to achieve the purpose of reinforcement, but also easily affects the performance of silica aerogels themselves. Therefore, in the prior art, fiber-reinforced materials and silica aerogels are often used to compound with each other to avoid affecting the thermal insulation performance of silica aerogels themselves; however, due to the high porosity of silica aerogels and the smooth surface of fiber-reinforced materials, the interface structure between aerogels and fiber-reinforced materials is very weak. Under load impact, cracks are very likely to appear between the interfaces and propagate along the interfaces, resulting in shedding and peeling between the reinforcing fibers and the aerogels, interface failure, aerogel fracture and other problems. Summary of the invention

[0004] In view of the problems existing in the above prior art, the purpose of the present invention is to provide a basalt fiber aerogel composite material, which can effectively improve the interface compatibility between the reinforcing fiber and the aerogel, and has the characteristics of strong interface bonding force, good corrosion resistance, no pollution, and excellent thermal insulation performance.

[0005] The purpose of the present invention is achieved through the following technical solutions: A basalt fiber aerogel composite material is obtained by the following method, comprising: Step 1: Preparation of interface modifier: First, anhydrous ethanol and deionized water were mixed to obtain a modified solvent, and then maleic anhydride and long-chain diaminosilane coupling agent (chemical formula: NH 2 (CH 2 ) 2 NH(CH 2 ) 3 Si(OCH3) 3 ) and silane coupling agent KH550 (chemical formula NH 2 CH 2 CH 2 CH 2 Si(OC 2 H 5 ) 3 ), and slowly add the modified solvent under vigorous stirring. After the addition is completed, continue stirring for 20 to 40 minutes until there is no obvious oily substance to obtain an interface modifier; Step 2, basalt fiber modification: First, basalt is evenly mixed in a high-speed mixer, and basalt fiber precursor is produced on an extruder with a length / diameter ratio of 40 to 45; then, after the extruded basalt fiber precursor is cooled, it is immersed in the interface modifier for modification; then, the modified basalt fiber precursor is bundled and wound by an automatic winding machine; finally, the bundled and wound fiber precursor is dried at room temperature and then placed in an oven for drying; Step 3, magnetron sputtering: First, the basalt fiber modified in the middle of step 2 is placed in the vacuum chamber of the magnetron sputtering equipment, and the magnetron sputtering target is TiO 2 , evacuate the chamber; then, introduce argon gas into the vacuum chamber, start the magnetron sputtering equipment to perform magnetron sputtering; finally, after the magnetron sputtering is completed, the magnetron sputtered fiber is removed and stored in an oven.

[0006] Based on further optimization of the above scheme, the volume ratio of maleic anhydride, long-chain diaminosilane coupling agent, silane coupling agent KH550, and modified solvent is 1.5-2.5:1-2:1-2:98-102.

[0007] Firstly, the silanol groups produced by hydrolysis of a specific formula of the interface modifier are fully condensed with the silanol groups on the surface of the basalt fiber on the basis of forming hydrogen bonds, thereby ensuring that the interface modifier is evenly and firmly attached to the surface of the basalt fiber; then, the titanium dioxide layer is prepared by magnetron sputtering, and the titanium dioxide is pulled by a large number of polar covalent bonds produced during the condensation of the interface modifier and bonded by van der Waals force, thereby effectively enhancing the compatibility of the titanium dioxide sputtered layer and the surface of the basalt fiber; at the same time, the titanium dioxide is pulled by the fully condensed interface modifier during magnetron sputtering, effectively ensuring the dispersion of titanium dioxide on the surface of the basalt fiber and reducing titanium dioxide agglomerates, thereby improving the density of the titanium dioxide coating layer, and enhancing the fluidity of the solution on the surface of the basalt fiber. When it is subsequently compounded with silica aerogel, as the porosity of the silica aerogel increases, the contact surface between the coating layer and the aerogel pores is increased by the fluidity of the solution, thereby improving the interface compatibility between the aerogel and the fiber.

[0008] In addition, by magnetron sputtering of titanium dioxide, Ti 4+ With four-coordinate (TiO 4 ) into the network structure of the fiber surface in the form of aerogel composites, and can react with SiO 2 The formation of a mixed skeleton of titanosilicate not only strengthens the fiber network structure, but also improves the connection strength between the fiber structure and the aerogel, thereby increasing the tensile strength; in addition, the dense titanium dioxide coating can delay the erosion of basalt fibers, generating Ti(OH) 4 , thus with Ti 4+ The combined effect enhances the fiber polymerization degree and effectively improves the alkali resistance of basalt fiber.

[0009] Based on further optimization of the above scheme, the volume ratio between anhydrous ethanol and deionized water in step 1 is 1:1.

[0010] Based on further optimization of the above scheme, the extrusion temperature of the extruder in step 2 is 180-220°C, and the extrusion speed is 90-110rpm. The soaking time of the basalt fiber in the interfacial modifier in step 2 is 25-35min. The drying temperature of the oven in step 2 is 90-100°C, and the drying time is 8-10h.

[0011] Based on the further optimization of the above scheme, the vacuum degree in step 3 is 3x10 -3 ~5x10 -3Pa, substrate temperature is 200-500°C, bias voltage is -100--200V; magnetron sputtering parameters are: target sputtering power 50-120W, working gas pressure 0.25-0.5Pa, sputtering time 30-40min. In step 3, the oven storage time is 8-12h, and the storage temperature is 30-50°C.

[0012] Based on the further optimization of the above scheme, after step three, the interface modified basalt fiber and the silica aerogel are further composited, specifically: first, take tetraethyl orthosilicate, ethanol and deionized water in a stirring bottle and stir them thoroughly to obtain a mixed solution, and then use hydrochloric acid to adjust the pH of the mixed solution to 1-2; then, the modified basalt fiber in step three is woven and layered, and the layered basalt fiber is added to the mixed solution adjusted to an acidic environment, the temperature is adjusted to 43-47°C, and after reacting for 0.8-1.5h, the pH is adjusted to 7-8 with ammonia water to obtain a composite material wet gel; finally, the composite material wet gel is poured into a mold, pressure filtered (at normal pressure) through a vacuum-assisted system, and then aged and dried to obtain a basalt fiber aerogel composite material.

[0013] Based on further optimization of the above scheme, the volume ratio of tetraethyl orthosilicate, ethanol and deionized water is 2.8-3.2:2.1-2.5:0.1.

[0014] Based on further optimization of the above scheme, the ratio of basalt fiber to mixed solution is: 0.1-0.2g: 35-45ml. The weaving method of the single layer of basalt fiber is interlaced winding of warp yarn and weft yarn. The concentration of hydrochloric acid is 0.05-0.15mol / L, and the concentration of ammonia water is 0.1mol / L.

[0015] Based on further optimization of the above scheme, the aging treatment process is: first, aging in anhydrous ethanol at a temperature of 55-65°C for 1.5-2.5 days; then, aging in an aging liquid at room temperature for 1.5-2.5 days; wherein the aging liquid includes trimethylchlorosilane, anhydrous ethanol and n-hexane, and their volume ratio is 8-12:10:48-52.

[0016] The following are the effects of the technical solution of the present invention: The present invention adopts an interface modifier composed of maleic anhydride, a long-chain diaminosilane coupling agent and a silane coupling agent KH550 to modify the surface of the basalt fiber, and cooperates with a combination method of magnetron sputtering deposition of a titanium dioxide layer. In the process of compounding the basalt fiber and the silicon dioxide aerogel, the interface homogeneity between the fiber and the aerogel is effectively improved, and sufficient and uniform contact between the fiber and the aerogel is ensured, so that problems such as cracks, crack extension, and separation between the fiber and the aerogel caused by external loads are avoided, thereby avoiding failure of mechanical properties, thermal insulation properties and the like of the composite material; the interface between the basalt fiber and the silicon dioxide aerogel is enhanced by using a specific interface modifier and magnetron sputtering deposition of titanium dioxide, so that not only the preparation process is simple and the raw material cost is low, but also the generation of three wastes is effectively avoided, and the preparation process has a high degree of greenness, so that it can be effectively used for large-scale production and manufacturing in industry, and has high practical value.

[0017] The basalt fiber aerogel composite material obtained by the present invention has the advantages of good mechanical properties, high thermal insulation performance, stable long-term performance, etc.; compared with traditional basalt fiber reinforced aerogel materials, the basalt fiber aerogel composite material provided by the present invention has a thermal conductivity reduced by more than 20%, and a mechanical property improved by more than 15%, and has excellent mechanical properties and thermal insulation properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 The figure is a flow chart of the surface modification of basalt fiber in an embodiment of the present invention.

[0019] Figure 2 is a SEM image of basalt fiber in an embodiment of the present invention; wherein, Figure 2 (a) is the surface image of basalt fiber without magnetron sputtering. Figure 2 (b) is the surface image of basalt fiber after magnetron sputtering. Figure 2 (c) is the corrosion pit image of basalt fiber after magnetron sputtering.

[0020] Figure 3 Schematic diagram of the weaving structure of basalt fiber in an embodiment of the present invention.

[0021] Among them, 10. unmodified fiber; 20. interface modifier; 30. modified fiber; 40. automatic winding machine. DETAILED DESCRIPTION

[0022] The present invention is further described in detail in conjunction with the following specific embodiments and drawings. The process, conditions, experimental methods, etc. for implementing the present invention, except for the contents specifically mentioned below, are all common knowledge and common common sense in the art, and the present invention has no special restrictions; in addition, the described embodiments are not intended to further limit the present invention.

[0023] Embodiment 1: A basalt fiber aerogel composite material is obtained by the following method, comprising: Step 1: Preparation of interface modifier: First, anhydrous ethanol and deionized water are mixed in a volume ratio of 1:1 to obtain a modified solvent; then, maleic anhydride (common maleic anhydride in the art can be used), long-chain diaminosilane coupling agent (chemical formula NH 2 (CH 2 ) 2 NH(CH 2 ) 3 Si(OCH3) 3 , the product purity is stable at more than 99%) and silane coupling agent KH550 (chemical formula is NH 2 CH 2 CH 2 CH 2 Si(OC 2 H 5 ) 3 , the product purity is stable at more than 99%), and under vigorous stirring (the stirring speed is determined according to the actual situation, generally 80r / min), slowly add the modified solvent, wherein the volume ratio of maleic anhydride, long-chain diaminosilane coupling agent, silane coupling agent KH550, and modified solvent is 1.5:1:1:98. After the addition is completed, continue stirring for 20 minutes until there is no obvious oily substance to obtain the interface modifier.

[0024] Step 2: Modification of basalt fiber: First, basalt is uniformly mixed in a high-speed mixer (stirring speed is generally 800r / min), and basalt fiber precursor is produced on an extruder with a length / diameter ratio of 40, the extrusion temperature is 180℃, and the extrusion speed is 90rpm; then, after the extruded basalt fiber precursor is cooled (it can be cooled by cold water or other methods, which can be set according to actual conditions), it is immersed in an interface modifier for 25min for modification; then, the modified basalt fiber precursor is bundled and wound by an automatic winding machine. For details of the modification process, see Figure 1 As shown; finally, the bundled and wound fiber filaments are dried at room temperature and then placed in an oven for drying. The drying temperature of the oven is 90°C and the drying time is 8 hours.

[0025] Step 3: Magnetron sputtering: First, place the modified basalt fiber in step 2 into the vacuum chamber of the magnetron sputtering equipment. The magnetron sputtering target is TiO 2 , vacuum, vacuum degree is 3x10 -3Pa; then, argon gas was introduced into the vacuum chamber, and the magnetron sputtering equipment was turned on for magnetron sputtering, wherein the substrate temperature was 200°C, the bias voltage was -100V, and the magnetron sputtering parameters were: target sputtering power 50W, working gas pressure 0.25Pa, and sputtering time 30min; finally, the magnetron sputtering was completed, and the fibers after magnetron sputtering were removed and stored in an oven for 8h at a storage temperature of 30°C.

[0026] Step 4: Composite of interface-modified basalt fiber and silica aerogel: First, take tetraethyl orthosilicate, ethanol and deionized water in a stirring bottle and stir them thoroughly to obtain a mixed solution, wherein the volume ratio of tetraethyl orthosilicate, ethanol and deionized water is 2.8:2.1:0.1, and then use hydrochloric acid to adjust the pH of the mixed solution to 2, and the concentration of hydrochloric acid is 0.05 mol / L; then, the modified basalt fiber in step 3 is woven and layered, and the weaving method of the single layer of basalt fiber is that the warp and weft yarns are interlaced (such as Figure 3 As shown), the stacked basalt fibers are added to a mixed solution adjusted to an acidic environment, the ratio of basalt fiber to the mixed solution is: 0.1g:35ml, the temperature is adjusted to 43°C, and after reacting for 0.8h, the pH is adjusted to 7 with ammonia water, and the concentration of ammonia water is 0.1mol / L to obtain a composite material wet gel; finally, the composite material wet gel is poured into a mold, pressure filtered (pressure is normal pressure) through a vacuum-assisted system, and then aged and dried, wherein the aging process is specifically as follows: first, aging in anhydrous ethanol at a temperature of 55°C for 2.5 days; then, aging in an aging solution at room temperature for 2.5 days; wherein the aging solution includes trimethylchlorosilane, anhydrous ethanol and n-hexane, and their volume ratio is 8:10:48, and the drying process can adopt a conventional drying process in the art, which is not specifically limited in this embodiment, to obtain a basalt fiber aerogel composite material.

[0027] Embodiment 2: A basalt fiber aerogel composite material is obtained by the following method, comprising: Step 1: Preparation of interface modifier: First, anhydrous ethanol and deionized water are mixed in a volume ratio of 1:1 to obtain a modified solvent; then, maleic anhydride (common maleic anhydride in the art can be used), long-chain diaminosilane coupling agent (chemical formula NH 2 (CH 2 ) 2 NH(CH 2 ) 3 Si(OCH3) 3 , the product purity is stable at more than 99%) and silane coupling agent KH550 (chemical formula is NH 2 CH 2 CH2 CH 2 Si(OC 2 H 5 ) 3 , the product purity is stable at more than 99%), and under vigorous stirring (the stirring speed is determined according to the actual situation, generally 100r / min), slowly add the modified solvent, wherein the volume ratio of maleic anhydride, long-chain diaminosilane coupling agent, silane coupling agent KH550, and modified solvent is 2:1.5:1.5:100. After the addition is completed, continue stirring for 30 minutes until there is no obvious oily substance to obtain the interface modifier.

[0028] Step 2: Modification of basalt fiber: First, basalt is uniformly mixed in a high-speed mixer (stirring speed is generally 900r / min), and basalt fiber precursor is produced on an extruder with a length / diameter ratio of 43, the extrusion temperature is 200℃, and the extrusion speed is 100rpm; then, after the extruded basalt fiber precursor is cooled (it can be cooled by cold water or other methods, which can be set according to actual conditions), it is immersed in an interface modifier for 30 minutes for modification; then, the modified basalt fiber precursor is bundled and wound by an automatic winding machine. For details of the modification process, see Figure 1 As shown; finally, the bundled and wound fiber filaments are dried at room temperature and then placed in an oven for drying. The drying temperature of the oven is 95°C and the drying time is 9h.

[0029] Step 3: Magnetron sputtering: First, place the modified basalt fiber in step 2 into the vacuum chamber of the magnetron sputtering equipment. The magnetron sputtering target is TiO 2 , vacuum, vacuum degree is 4x10 -3 Pa; then, argon gas was introduced into the vacuum chamber, and the magnetron sputtering equipment was turned on for magnetron sputtering, wherein the substrate temperature was 350°C, the bias voltage was -150V, and the magnetron sputtering parameters were: target sputtering power 85W, working gas pressure 0.35Pa, and sputtering time 35min; finally, the magnetron sputtering was completed, and the fibers after magnetron sputtering were removed and stored in an oven for 10h at a storage temperature of 40°C.

[0030] Step 4: Composite of interface-modified basalt fiber and silica aerogel: First, take tetraethyl orthosilicate, ethanol and deionized water in a stirring bottle and stir them thoroughly to obtain a mixed solution, wherein the volume ratio of tetraethyl orthosilicate, ethanol and deionized water is 3:2.3:0.1, and then use hydrochloric acid to adjust the pH of the mixed solution to 1, and the concentration of hydrochloric acid is 0.15 mol / L; then, the modified basalt fiber in step 3 is woven and layered, and the weaving method of the single layer of basalt fiber is that the warp and weft yarns are interlaced (such as Figure 3As shown), the stacked basalt fibers are added to a mixed solution adjusted to an acidic environment, the ratio of basalt fiber to the mixed solution is: 0.15g:40ml, the temperature is adjusted to 45°C, and after reacting for 1.2h, the pH is adjusted to 8 with ammonia water, and the concentration of ammonia water is 0.1mol / L to obtain a composite material wet gel; finally, the composite material wet gel is poured into a mold, pressure filtered (pressure is normal pressure) through a vacuum-assisted system, and then aged and dried, wherein the aging process is specifically as follows: first, aging in anhydrous ethanol at a temperature of 60°C for 2 days; then, aging in an aging solution at room temperature for 2 days; wherein the aging solution includes trimethylchlorosilane, anhydrous ethanol and n-hexane, and their volume ratio is 10:10:50, and the drying process can adopt a conventional drying process in the art, which is not specifically limited in this embodiment, to obtain a basalt fiber aerogel composite material.

[0031] Embodiment 3: A basalt fiber aerogel composite material is obtained by the following method, comprising: Step 1: Preparation of interface modifier: First, anhydrous ethanol and deionized water are mixed in a volume ratio of 1:1 to obtain a modified solvent; then, maleic anhydride (common maleic anhydride in the art can be used), long-chain diaminosilane coupling agent (chemical formula NH 2 (CH 2 ) 2 NH(CH 2 ) 3 Si(OCH3) 3 , the product purity is stable at more than 99%) and silane coupling agent KH550 (chemical formula is NH 2 CH 2 CH 2 CH 2 Si(OC 2 H 5 ) 3 , the product purity is stable at more than 99%), and under vigorous stirring (the stirring speed is determined according to the actual situation, generally 120r / min), slowly add the modified solvent, wherein the volume ratio of maleic anhydride, long-chain diaminosilane coupling agent, silane coupling agent KH550, and modified solvent is 2.5:2:2:102. After the addition is completed, continue stirring for 40 minutes until there is no obvious oily substance to obtain the interface modifier.

[0032] Step 2: Modification of basalt fiber: First, basalt is uniformly mixed in a high-speed mixer (stirring speed is generally 1000r / min), and basalt fiber precursor is produced on an extruder with a length / diameter ratio of 45, the extrusion temperature is 220℃, and the extrusion speed is 110rpm; then, after the extruded basalt fiber precursor is cooled (it can be cooled by cold water or other methods, which can be set according to actual conditions), it is immersed in an interface modifier for 35min for modification; then, the modified basalt fiber precursor is bundled and wound by an automatic winding machine. For details of the modification process, see Figure 1 As shown; finally, the bundled and wound fiber filaments are dried at room temperature and then placed in an oven for drying. The drying temperature of the oven is 100°C and the drying time is 10 hours.

[0033] Step 3: Magnetron sputtering: First, place the modified basalt fiber in step 2 into the vacuum chamber of the magnetron sputtering equipment. The magnetron sputtering target is TiO 2 , vacuum, vacuum degree is 5x10 -3 Pa; then, argon gas was introduced into the vacuum chamber, and the magnetron sputtering equipment was turned on for magnetron sputtering, wherein the substrate temperature was 500°C, the bias voltage was -200V, and the magnetron sputtering parameters were: target sputtering power 120W, working gas pressure 0.5Pa, and sputtering time 40min; finally, the magnetron sputtering was completed, and the fibers after magnetron sputtering were removed and stored in an oven for 12h at a storage temperature of 50°C.

[0034] Step 4: Composite of interface-modified basalt fiber and silica aerogel: First, tetraethyl orthosilicate, ethanol and deionized water are fully stirred in a stirring bottle to obtain a mixed solution, wherein the volume ratio of tetraethyl orthosilicate, ethanol and deionized water is 3.2:2.5:0.1, and then hydrochloric acid is used to adjust the pH of the mixed solution to 1, and the concentration of hydrochloric acid is 0.15 mol / L; then, the modified basalt fiber in step 3 is woven and layered, and the weaving method of the single layer of basalt fiber is that the warp and weft yarns are interlaced (such as Figure 3As shown), the stacked basalt fibers are added to a mixed solution adjusted to an acidic environment, the ratio of basalt fiber to the mixed solution is: 0.2g:45ml, the temperature is adjusted to 47°C, and after reacting for 1.5h, the pH is adjusted to 7 with ammonia water, and the concentration of ammonia water is 0.1mol / L to obtain a composite material wet gel; finally, the composite material wet gel is poured into a mold, pressure filtered (at normal pressure) through a vacuum-assisted system, and then aged and dried, wherein the aging process is specifically as follows: first, aging in anhydrous ethanol at a temperature of 65°C for 1.5 days; then, aging in an aging solution at room temperature for 1.5 days; wherein the aging solution includes trimethylchlorosilane, anhydrous ethanol and n-hexane, and their volume ratio is 12:10:52, and the drying process can adopt a conventional drying process in the art, which is not specifically limited in this embodiment, to obtain a basalt fiber aerogel composite material.

[0035] Comparative Example 1: A fiber aerogel composite material is obtained by the following method, comprising: Step 1: Preparation of interface modifier: First, anhydrous ethanol and deionized water are mixed in a volume ratio of 1:1 to obtain a modified solvent; then, maleic anhydride (common maleic anhydride in the art can be used) and silane coupling agent KH550 (chemical formula: NH 2 CH 2 CH 2 CH 2 Si(OC 2 H 5 ) 3 , the product purity is stable at more than 99%), and under vigorous stirring (the stirring speed is determined according to the actual situation, generally 100r / min), slowly add the modified solvent, wherein the volume ratio of maleic anhydride, silane coupling agent KH550, and modified solvent is 2:1.5:100. After the addition is completed, continue stirring for 30 minutes until there is no obvious oily substance to obtain the interface modifier.

[0036] Step 2: Basalt fiber modification: the same as the step in Example 2. Step 3: Magnetron sputtering: the same as the step in Example 2. Step 4: Composite of interface-modified basalt fiber and silica aerogel: the same as the step in Example 2.

[0037] Comparative Example 2: A fiber aerogel composite material is obtained by the following method, comprising: Step 1: Preparation of interface modifier: First, anhydrous ethanol and deionized water are mixed in a volume ratio of 1:1 to obtain a modified solvent; then, maleic anhydride (common maleic anhydride in the art can be used), long-chain diaminosilane coupling agent (chemical formula NH 2 (CH2 ) 2 NH(CH 2 ) 3 Si(OCH3) 3 , product purity is stable at more than 99%) and silane coupling agent KH560 (chemical formula is CH 2 CH(O)CH 2 O(CH 2 ) 3 Si(OCH 3 ) 3 , the product purity is stable at more than 99%), and under vigorous stirring (the stirring speed is determined according to the actual situation, generally 100r / min), slowly add the modified solvent, wherein the volume ratio of maleic anhydride, long-chain diaminosilane coupling agent, silane coupling agent KH560, and modified solvent is 2:1.5:1.5:100. After the addition is completed, continue stirring for 30 minutes until there is no obvious oily substance to obtain the interface modifier.

[0038] Step 2: Basalt fiber modification: the same as the step in Example 2. Step 3: Magnetron sputtering: the same as the step in Example 2. Step 4: Composite of interface-modified basalt fiber and silica aerogel: the same as the step in Example 2.

[0039] Comparative Example 3: A fiber aerogel composite material is obtained by the following method, comprising: Step 1: Preparation of interface modifier: the same as the step in Example 2. Step 2: Modification of basalt fiber: the same as the step in Example 2.

[0040] Step 3: Magnetron sputtering: First, place the modified basalt fiber in step 2 into the vacuum chamber of the magnetron sputtering equipment. The magnetron sputtering target is Ti. Vacuum the chamber to a vacuum degree of 4x10 -3 Pa; then, argon gas was introduced into the vacuum chamber, and the magnetron sputtering equipment was turned on for magnetron sputtering, wherein the substrate temperature was 350°C, the bias voltage was -150V, and the magnetron sputtering parameters were: target sputtering power 85W, working gas pressure 0.35Pa, and sputtering time 35min; finally, the magnetron sputtering was completed, and the fibers after magnetron sputtering were removed and stored in an oven for 10h at a storage temperature of 40°C.

[0041] Step 4: Composite of interface-modified basalt fiber and silica aerogel: the same as the steps in Example 2.

[0042] The performance tests were conducted on the basalt fiber aerogel composite materials prepared in Examples 1 to 3 and the basalt fiber aerogel composite materials prepared in Comparative Examples 1 to 3, respectively. The specific performances are shown in the following table:

[0043] It can be seen from the above table that when the bulk density and porosity are roughly the same, the use of specific interface modifiers and magnetron sputtering TiO 2 The surface modification of basalt fiber by the method can effectively improve the interface compatibility between basalt fiber and silica aerogel, thereby reducing the thermal conductivity of the composite material as a whole and improving the mechanical properties of the composite material as a whole (i.e., compressive strength, bending elastic modulus, etc.); while Comparative Examples 1 to 2 do not use the specific interface modifier of the present application, and Comparative Example 3 does not use TiO 2 Magnetron sputtering is performed. Therefore, compared with the composite materials of the present application, the interface compatibility between the basalt fiber and the silica aerogel in the composite materials obtained by them is low, the bonding strength is small, and it is impossible to form an integral material without obvious microscopic boundaries (thus, the synergistic effect between the two materials cannot be fully exerted), which directly affects its thermal insulation (i.e. thermal conductivity) and mechanical properties. That is, compared with Examples 1 to 3, Comparative Examples 1 to 3 have higher thermal conductivity and lower mechanical properties (i.e. compressive strength, bending elastic modulus, etc.).

Claims

1. A basalt fiber aerogel composite material, characterized in that: Obtained through the following methods, including: Step 1: Preparation of interface modifier; Step 2: Basalt fiber modification; Step 3, magnetron sputtering: First, the basalt fiber modified in step 2 is placed in the vacuum chamber of the magnetron sputtering equipment, the magnetron sputtering target is TiO2, and the vacuum is evacuated; then, argon gas is introduced into the vacuum chamber, and the magnetron sputtering equipment is turned on for magnetron sputtering; finally, after the magnetron sputtering is completed, the fiber after magnetron sputtering is removed and placed in an oven for storage; Step 4, composite between interface modified basalt fiber and silica aerogel: first, take ethyl orthosilicate, ethanol and deionized water in a stirring bottle and stir them thoroughly to obtain a mixed solution, and then use hydrochloric acid to adjust the pH of the mixed solution to 1-2; then, weave the modified basalt fiber in step 3 and lay it in layers, and add the laid basalt fiber to the mixed solution adjusted to an acidic environment, the ratio of basalt fiber to the mixed solution is: 0.1-0.2g: 35-45ml, adjust the temperature to 43-47°C, react for 0.8-1.5h, and adjust the pH to 7-8 with ammonia water to obtain a composite material wet gel; finally, pour the composite material wet gel into a mold, pressure filter it through a vacuum-assisted system, and then age and dry it to obtain a basalt fiber aerogel composite material.

2. The basalt fiber aerogel composite material according to claim 1, characterized in that: The step 1 is specifically as follows: first, anhydrous ethanol is mixed with deionized water to obtain a modified solvent, then maleic anhydride, a long-chain diaminosilane coupling agent and a silane coupling agent KH550 are weighed respectively, and the modified solvent is slowly added dropwise under vigorous stirring, and after the addition is completed, stirring is continued for 20 to 40 minutes until no obvious oily matter is left, thereby obtaining an interface modifier; wherein the volume ratio of maleic anhydride, the long-chain diaminosilane coupling agent, the silane coupling agent KH550 and the modified solvent is 1.5 to 2.5:1 to 2:1 to 2:98 to 102.

3. The basalt fiber aerogel composite material according to claim 2, characterized in that: The volume ratio of anhydrous ethanol to deionized water in step 1 is 1:

1.

4. The basalt fiber aerogel composite material according to claim 3, characterized in that: The step 2 is specifically as follows: first, basalt is uniformly mixed in a high-speed mixer, and basalt fiber precursor is produced on an extruder with a length / diameter ratio of 40 to 45, the extrusion temperature of the extruder is 180 to 220° C., and the extrusion speed is 90 to 110 rpm; then, after the extruded basalt fiber precursor is cooled, it is immersed in an interface modifier for modification; then, the modified basalt fiber precursor is bundled and wound by an automatic winding machine; finally, the bundled and wound fiber precursor is dried at room temperature and then placed in an oven for drying.

5. The basalt fiber aerogel composite material according to claim 4, characterized in that: The drying temperature of the oven is 90-100° C., and the drying time is 8-10 hours.

6. The basalt fiber aerogel composite material according to claim 1, characterized in that: The vacuum degree in step 3 is 3x10 -3 ~5x10 -3 Pa, substrate temperature is 200~500℃, bias voltage is -100~-200V; magnetron sputtering parameters are: target sputtering power is 50~120W, working gas pressure is 0.25~0.5Pa, sputtering time is 30~40min.

7. The basalt fiber aerogel composite material according to claim 1, characterized in that: The volume ratio of the tetraethyl orthosilicate, ethanol and deionized water is 2.8-3.2:2.1-2.5:0.

1.

8. The basalt fiber aerogel composite material according to claim 7, characterized in that: The concentration of the hydrochloric acid is 0.05-0.15 mol / L, and the concentration of the ammonia water is 0.1 mol / L.

9. The basalt fiber aerogel composite material according to claim 1, characterized in that: The chemical treatment process is: first, aging in anhydrous ethanol at a temperature of 55-65° C. for 1.5-2.5 days; then, aging in an aging solution at room temperature for 1.5-2.5 days; wherein the aging solution includes trimethylchlorosilane, anhydrous ethanol and n-hexane, and their volume ratio is 8-12:10:48-52.

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