Preparation method and preparation device of silicon oxide aerogel fibrofelt composite material

Abstract

The invention discloses a preparation method and a preparation device of a silicon oxide aerogel fiber felt composite material, and belongs to the technical field of gel fiber felt preparation. Comprising the following steps that a silicon source solution and a catalyst solution are obtained and placed in corresponding feeding tanks respectively, the silicon source solution and the catalyst solution flow into a coil pipe of ultrasonic equipment through a three-way pipeline according to the proportion of 1: 1 to be mixed, a fiber felt is wound around a reel, and after one end of the fiber felt is inserted into a clamping groove of a coiling machine, the silicon source solution and the catalyst solution are wound; the preparation method comprises the following steps: winding a fiber felt on another reel under the conveying of a coiling machine, spraying a gel solvent into a soaking bin, spraying the gel solvent onto the fiber felt in the conveying process of the fiber felt to obtain a wet gel fiber felt, soaking the wet gel fiber felt into an organic solution for a preset time, and then drying to obtain the gel fiber felt. The silicon oxide aerogel fiber felt composite material is obtained. The gel reaction process can be effectively controlled, and waste of chemical raw materials and cleaning time caused by gelling of redundant solutions is avoided.

Description

Technical Field

[0001] The invention belongs to the technical field of gel fiber felt preparation, and in particular relates to a method for preparing a silicon oxide aerogel fiber felt composite material and a preparation device thereof. Background Art

[0002] Since 2015, the production and sales of new energy vehicles in my country have grown steadily. At present, China has become one of the major consumers of new energy vehicles in the world. However, with the increase in the number of new energy vehicles and the improvement of their performance, their safety issues have become more prominent. As the core component of the vehicle, the power battery is related to the safety of the vehicle, and for the battery, the biggest threat is the thermal runaway of the battery. Silica aerogel has a three-dimensional nanoporous network structure, which gives it the characteristics of low density, high specific surface area, and large porosity. Its unique structure can effectively limit gas convection and solid thermal conductivity, and it is an ideal high-performance insulation material. Using aerogel fiber felt as a thermal protection material for power battery cells can delay the thermal runaway event of adjacent cells and provide effective escape time for drivers and passengers.

[0003] Conventional aerogel felt is prepared by mixing fiber felt with prepared silica sol and gelling the mixture. When fiber felt and silica sol are mixed in this way, the silica sol cannot be fully used, resulting in waste of silica sol, and the excess gel needs to be cleaned after gelling. Therefore, a continuous and stable preparation method is needed to solve the problem of waste of raw materials and time in the existing technology. Summary of the invention

[0004] Purpose of the invention: To provide a continuous preparation method of a silica aerogel fiber felt composite material, which solves the above-mentioned problems existing in the prior art.

[0005] Technical solution: A continuous preparation method of a silica aerogel fiber felt composite material, comprising the following steps: Prepare gel solution: A silicon source solution and a catalyst solution are obtained and placed in corresponding feed tanks respectively, and the silicon source solution and the catalyst solution flow into the coil of the ultrasonic device through a three-way pipe in a ratio of 1:1 to mix and obtain a gel solvent; Conveying fiber felt: The fiber felt is wound on a reel, and after one end of the fiber felt is inserted into the slot of the reeling machine, the fiber felt is wound on another reel under the conveyance of the reeling machine, so that the fiber felt moves from one reel to another reel to form the conveyance of the fiber felt; Preparation of silica aerogel fiber felt composite materials: The gel solvent is sprayed into the impregnation bin. During the transportation process, the fiber felt slowly passes through the impregnation bin so that the fiber felt is sprayed with the gel solvent to obtain a wet gel fiber felt. The wet gel fiber felt is soaked in an organic solution for a predetermined time to replace the solvent. After the solvent replacement is completed, the composite fiber felt is taken out to obtain the composite fiber felt. After the composite fiber felt is dried, a silica aerogel fiber felt composite material is obtained.

[0006] Preferably, the silicon source solution is prepared by mixing a silicon source and ethanol in a mass ratio of 1:(0.5-2.5), wherein the silicon source is methyl orthosilicate or ethyl orthosilicate.

[0007] Preferably, the catalyst solution is prepared by mixing a catalyst, ethanol and water in a mass ratio of 1: (15-30): 2.5, wherein the catalyst is aqueous ammonia or ammonium fluoride solution.

[0008] Preferably, the ultrasound is used at a vibration frequency of 25-40 kHz and a temperature of 30-60° C. to mix the silicon source solution and the catalyst solution flowing into the coil to obtain a gel solvent.

[0009] Preferably, the fiber felt is one of pre-oxidized needle felt, glass fiber surface felt, and ceramic fiber felt, and the thickness of the fiber felt is 0.2-5.1 mm.

[0010] Preferably, the fiber felt moves from one rotating shaft to another rotating shaft at a moving speed of 0.2-1.0 m / min.

[0011] Preferably, the organic solvent is one of ethanol, methanol, acetonitrile, isopropanol or acetone.

[0012] Preferably, the replacement time of the wet gel fiber felt soaked in the organic solution is 30-50 hours.

[0013] A preparation device for a silica aerogel fiber felt composite material is prepared by the above-mentioned continuous preparation method of a silica aerogel fiber felt composite material, comprising two groups of feeding tanks, the feeding tanks are respectively used to hold a silicon source solution and a catalyst solution, the feeding tanks are connected to the coil feeding end of an ultrasonic device through a three-way pipe, the discharge end of the coil is connected to a spray head, a soaking bin is provided below the spray head, reels are respectively installed on two opposite sides of the soaking bin, the reels are used to wind the fiber felt, a winding machine is placed between a rotating shaft and the soaking bin, and under the drive of the winding machine, the fiber felt passes from one reel through between the soaking bin and the spray head and is wound onto another reel.

[0014] Beneficial effects: The present invention relates to a continuous preparation method of a silica aerogel fiber felt composite material, in which a silicon source solution and a catalyst solution are respectively contained in separate feeding tanks, which are connected to the feeding tanks through a three-way pipe, and the silicon source solution and the catalyst solution in the feeding tanks are transported to the coil of an ultrasonic device for mixing to obtain a gel solvent, which can effectively control the gel reaction process and avoid the waste of chemical raw materials and cleaning time caused by the gelation of excess solution.

[0015] Secondly, by placing the silicon source solution and the catalyst solution in separate feeding tanks, they can be stably stored for a long time. During the production process, they can be turned on and used immediately and shut down and stopped immediately, thereby realizing the continuous preparation of silica aerogel fiber felt composite materials and greatly improving the production efficiency of silica aerogel fiber felt composite materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a flowchart of the production process of the present invention; Figure 2 It is an overall schematic diagram of the device of the present invention.

[0017] Figure 2 The figures are marked as follows: 1. feeding tank; 2. three-way pipe; 3. ultrasonic equipment; 4. coil; 5. reel; 6. immersion bin; 7. spray head. DETAILED DESCRIPTION

[0018] like Figure 1 to Figure 2 As shown, the present invention provides a technical solution: a continuous preparation method of a silica aerogel fiber felt composite material, comprising the following steps: Prepare gel solution: A silicon source solution and a catalyst solution are obtained and placed in corresponding feeding tanks 1 respectively, wherein the silicon source solution is prepared by mixing a silicon source and ethanol in a mass ratio of 1: (0.5-2.5), wherein the silicon source is methyl orthosilicate or ethyl orthosilicate, and the catalyst solution is prepared by mixing a catalyst, ethanol and water in a mass ratio of 1: (15-30): 2.5, wherein the catalyst is ammonia water or ammonium fluoride solution, and the silicon source solution and the catalyst solution flow into the coil 4 of the ultrasonic device 3 through the three-way pipe 2 in a ratio of 1:1 for mixing, wherein the ultrasound is used at a vibration frequency of 25-40kHz and a temperature of 30-60°C to mix the silicon source solution and the catalyst solution flowing into the coil 4 to obtain a gel solvent.

[0019] Conveying fiber felt: The fiber felt is wound on the reel 5, and the fiber felt is one of pre-oxidized needle-punched felt, glass fiber surface felt, and ceramic fiber felt. The thickness of the fiber felt is 0.2-5.1 mm. After one end of the fiber felt is inserted into the slot of the winder, the fiber felt is wound onto another reel 5 under the transportation of the winder. The fiber felt moves from one rotating shaft to another rotating shaft at a moving speed of 0.2-1.0 m / min, so that the fiber felt moves from one reel 5 to another reel 5 to form the transportation of the fiber felt.

[0020] Preparation of silica aerogel fiber felt composite materials: The gel solvent is sprayed into the impregnation bin 6. During the transportation process, the fiber felt slowly passes through the impregnation bin 6, so that the fiber felt is sprayed with the gel solvent to obtain a wet gel fiber felt. The wet gel fiber felt is immersed in an organic solution for a predetermined time to replace the solvent, wherein the organic solvent is one of ethanol, methanol, acetonitrile, isopropanol or acetone. The replacement time of the wet gel fiber felt in the organic solution is 30-50 hours. After the solvent replacement is completed, the composite fiber felt is taken out to obtain the composite fiber felt. After the composite fiber felt is dried, a silica aerogel fiber felt composite material is obtained.

[0021] Through the above-mentioned continuous preparation method of the silica aerogel fiber felt composite material and the continuous device of the silica aerogel fiber felt composite material, the present invention can realize the following working process: A preparation device for a silicon oxide aerogel fiber felt composite material, comprising two groups of feeding tanks 1, a three-way pipe 2, an ultrasonic device 3, a spray head 7, a soaking bin 6, a reel 5 and a winding machine, wherein the feeding tank 1 is used to contain a silicon source solution and a catalyst solution respectively, the feeding tank 1 is connected to a coil 4 in the ultrasonic device 3 through a three-way pipe 2, the silicon source solution and the catalyst solution contained in the feeding tank 1 flow into the coil 4 of the ultrasonic device 3 through the three-way pipe 2, and the silicon source solution and the catalyst solution are mixed with each other through ultrasonic vibration to obtain a gel solvent, the discharge end of the coil 4 is connected to the spray head 7, a soaking bin 6 is provided below the spray head 7, and the silicon source solution and the catalyst solution are mixed with each other through the spray head 7 to obtain a gel solvent, 6, reels 5 are respectively installed on the two opposite sides of the impregnation bin 6, and the reels 5 are used to wind the fiber felt, and a winding machine is placed between one rotating shaft and the impregnation bin 6. Driven by the winding machine, the fiber felt passes through the impregnation bin 6 and the spray head 7 from one reel 5 and is then wound onto the other reel 5. When the fiber felt passes between the feed bin and the spray head 7, the gel solvent is sprayed onto the fiber felt through the spray head 7 to obtain a wet gel fiber felt, and the wet gel fiber felt is soaked in an organic solution for a predetermined time to perform solvent replacement, and after the solvent replacement is completed, it is taken out to obtain a composite fiber felt, and the composite fiber felt is dried to obtain a silica aerogel fiber felt composite material.

[0022] Example 1 A silicon source solution with a mass ratio of 1:2.5 of ethyl orthosilicate to ethanol and a catalyst solution with a mass ratio of 1:30:2.5 of ammonia water to ethanol to water are respectively prepared in two feeding tanks 1. The two are mixed in equal mass through a three-way and then passed through an ultrasonic device 3 with a vibration frequency of 40kHz and a temperature of 60°C before entering the feed bin for standby use. A pre-oxidized needle felt coil with a thickness of 3.5 mm is placed on a reel 5 at one end of the coiler, the coiler speed is fixed at 0.8 m / min, and one end of the fiber felt coil is slowly passed through the impregnation bin 6. After impregnation, it is wound onto another reel 5 for winding. The pre-oxidized needle felt coil after impregnation is placed in ethanol for solvent replacement for 40 hours, and then supercritically dried to obtain a silica aerogel fiber felt composite material.

[0023] The obtained silica aerogel pre-oxidized fiber felt has good appearance, uniform impregnation, and stable thickness within the range of 3.0-3.5mm. The thermal conductivity at room temperature is 0.019W / (m•k), the thermal conductivity at 100℃ is 0.021W / (m•k), the compression rate at 2MPa is 65.0%, and the specific heat capacity at room temperature is 0.95J / (g•k).

[0024] Example 2 A silicon source solution with a mass ratio of 1:0.5 of ethyl orthosilicate to ethanol and a catalyst solution with a mass ratio of 1:14:2.5 of ammonia water to ethanol to water are respectively prepared in two feeding tanks 1. The two are mixed in equal mass through a three-way and then passed through an ultrasonic device 3 with a vibration frequency of 25kHz and a temperature of 40°C before entering the feed bin for standby use. A glass fiber surface felt coil with a thickness of 1.0 mm is placed on a reel 5 at one end of a coiling machine, the coiling machine speed is fixed at 1.0 m / min, and one end of the glass fiber surface felt is slowly passed through the impregnation bin 6. After impregnation, it is wound onto another reel 5 for winding. The impregnated glass fiber surface felt coil is placed in ethanol for solvent replacement for 40 hours, and then supercritically dried to obtain a silica aerogel fiber felt composite material.

[0025] The obtained silica aerogel glass fiber felt has good appearance, uniform impregnation, and stable thickness in the range of 0.95-1.1mm. The thermal conductivity at room temperature is 0.020W / (m•k), the thermal conductivity at 300℃ is 0.035W / (m•k), the compression rate is 55% at 2MPa, and the specific heat capacity at room temperature is 0.67J / (g•k).

[0026] Example 3 A silicon source solution with a mass ratio of 1:1 of ethyl orthosilicate: ethanol and a catalyst solution with a mass ratio of 1:16.5:2.5 of ammonia water: ethanol: water are respectively prepared in two feeding tanks 1. The two are mixed in equal mass through a three-way and then passed through an ultrasonic device 3 with a vibration frequency of 35kHz and a temperature of 50°C before entering the feed bin for standby. A pre-oxidized needle felt coil with a thickness of 5.0 mm is placed on a reel 5 at one end of the coiling machine, the coiling machine speed is fixed at 0.5 m / min, and one end of the pre-oxidized needle felt coil is slowly passed through the impregnation bin 6. After impregnation, it is wound onto another reel 5 for winding. The impregnated pre-oxidized needle felt coil is placed in ethanol for solvent replacement for 40 hours, and then supercritically dried to obtain a silica aerogel fiber felt composite material.

[0027] The obtained silica aerogel preoxidized silk fiber felt has good appearance, uniform impregnation, stable thickness within the range of 4.5-5.1 mm, thermal conductivity of 0.0237 W / (m•k) at room temperature, and compression rate of 47% at 2 MPa.

[0028] Example 4 A silicon source solution with a mass ratio of 1:1.2 of ethyl orthosilicate to ethanol and a catalyst solution with a mass ratio of 1:18.5:2.5 of ammonia water to ethanol to water are respectively prepared in two feeding tanks 1. The two are mixed in equal mass through a three-way and then passed through an ultrasonic device 3 with a vibration frequency of 35Hz and a temperature of 50°C before entering the feed bin for standby use. A ceramic fiber felt coil with a thickness of 4.1mm is placed on a reel 5 at one end of the coiling machine, the coiling machine speed is fixed at 0.5m / min, and one end of the fiber felt coil is slowly passed through the impregnation bin 6. After the impregnation is completed, it is wound onto another reel 5 for winding. The impregnated pre-oxidized needle felt coil is placed in ethanol for solvent replacement for 40h, and then supercritically dried to obtain a silica aerogel fiber felt composite material.

[0029] The obtained silica aerogel ceramic fiber felt has good appearance, uniform impregnation, and stable thickness in the range of 3.7-4.3mm. The thermal conductivity at room temperature is 0.0185W / (m•k), the thermal conductivity at 500℃ is 0.045W / (m•k), the compression rate is 50% at 2MPa, and the specific heat capacity at room temperature is 0.84J / (g•k).

[0030] Example 5 A silicon source solution with a mass ratio of 1:2 of ethyl orthosilicate to ethanol and a catalyst solution with a mass ratio of 1:27:2.5 of ammonia water to ethanol to water are respectively prepared in two feeding tanks 1. The two are mixed in equal mass through a three-way and then passed through an ultrasonic device 3 with a vibration frequency of 35kHz and a temperature of 60°C before entering the feed bin for standby use. A pre-oxidized needle felt coil with a thickness of 1.2 mm is placed on a reel 5 at one end of the coiler, the coiler speed is fixed at 1.0 m / min, and one end of the pre-oxidized needle felt coil is slowly passed through the impregnation bin 6. After impregnation, it is wound onto another reel 5 for winding. The pre-oxidized needle felt coil after impregnation is placed in ethanol for solvent replacement for 40 hours, and then supercritically dried to obtain a silica aerogel fiber felt composite material.

[0031] The obtained silica aerogel preoxidized silk fiber felt has good appearance, uniform impregnation, stable thickness in the range of 0.8-1.2 mm, thermal conductivity of 0.0179 W / (m•k) at room temperature, and compression rate of 60% at 2 MPa.

[0032] The preferred embodiments of the present invention are described in detail above; however, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, various equivalent transformations can be made to the technical solutions of the present invention, and these equivalent transformations all belong to the protection scope of the present invention.

Claims

1. A continuous preparation method of a silica aerogel fiber felt composite material, characterized in that: The following steps are involved: Prepare gel solution: A silicon source solution and a catalyst solution are obtained and placed in corresponding feed tanks (1) respectively, and the silicon source solution and the catalyst solution flow into the coil (4) of the ultrasonic device (3) through a three-way pipe (2) in a ratio of 1:1 to mix, thereby obtaining a gel solvent; Conveying fiber felt: The fiber felt is wound on a reel (5), one end of the fiber felt is inserted into a slot of a winding machine, and then the fiber felt is wound onto another reel (5) under the conveyance of the winding machine, so that the fiber felt moves from one reel (5) to another reel (5) to form the conveyance of the fiber felt; Preparation of silica aerogel fiber felt composite materials: The gel solvent is sprayed into the impregnation bin (6); during the transportation process, the fiber felt slowly passes through the impregnation bin (6) so that the fiber felt is sprayed with the gel solvent to obtain a wet gel fiber felt; the wet gel fiber felt is immersed in an organic solution for a predetermined time to perform solvent replacement; after the solvent replacement is completed, the composite fiber felt is taken out to obtain the composite fiber felt; and the composite fiber felt is dried to obtain a silica aerogel fiber felt composite material.

2. The method for continuously preparing a silica aerogel fiber felt composite material according to claim 1, characterized in that: The silicon source solution is prepared by mixing a silicon source and ethanol in a mass ratio of 1:(0.5-2.5), wherein the silicon source is methyl orthosilicate or ethyl orthosilicate.

3. The method for continuously preparing a silica aerogel fiber felt composite material according to claim 1, characterized in that: The catalyst solution is prepared by mixing a catalyst, ethanol and water in a mass ratio of 1: (15-30): 2.5, wherein the catalyst is ammonia water or ammonium fluoride solution.

4. The method for continuously preparing a silica aerogel fiber felt composite material according to claim 1, characterized in that: The ultrasound is used to mix the silicon source solution and the catalyst solution flowing into the coil (4) at a vibration frequency of 25-40 kHz and a temperature of 30-60° C. to obtain a gel solvent.

5. The method for continuously preparing a silica aerogel fiber felt composite material according to claim 1, characterized in that: The fiber felt is one of pre-oxidized needle felt, glass fiber surface felt, and ceramic fiber felt, and the thickness of the fiber felt is 0.2-5.1 mm.

6. The method for continuously preparing a silica aerogel fiber felt composite material according to claim 1, characterized in that: The fiber mat moves from one rotating shaft to another rotating shaft at a moving speed of 0.2-1.0 m / min.

7. The method for continuously preparing a silica aerogel fiber felt composite material according to claim 1, characterized in that: The organic solvent is one of ethanol, methanol, acetonitrile, isopropanol or acetone.

8. The method for continuously preparing a silica aerogel fiber felt composite material according to claim 1, characterized in that: The replacement time of the wet gel fiber felt soaked in the organic solution is 30-50 hours.

9. The method for continuously preparing a silica aerogel fiber felt composite material according to claim 1, characterized in that: The drying process is one of normal pressure drying, vacuum drying or supercritical drying.

10. A preparation device for a silica aerogel fiber felt composite material, wherein the silica aerogel fiber felt composite material is prepared by the continuous preparation method for a silica aerogel fiber felt composite material according to any one of claims 1 to 9, characterized in that: The invention comprises two groups of feeding tanks (1), wherein the feeding tanks (1) are used to contain a silicon source solution and a catalyst solution respectively. The feeding tanks (1) are connected to the feeding end of a coil (4) of an ultrasonic device (3) via a three-way pipe (2), and the discharging end of the coil (4) is connected to a spray head (7). A soaking bin (6) is provided below the spray head (7), and reels (5) are respectively installed on two opposite sides of the soaking bin (6). The reels (5) are used to wind a fiber felt, wherein a winding machine is placed between one of the rotating shafts and the soaking bin (6). Under the drive of the winding machine, the fiber felt passes from one reel (5) through between the soaking bin (6) and the spray head (7) and is then wound onto another reel (5).

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