High-temperature-resistant high-strength composite felt and preparation method thereof

Abstract

The present application relates to the technical field of non-woven materials, and particularly relates to a high-temperature-resistant and high-strength composite felt and a preparation method thereof, the composite felt is composed of a reinforcing framework and oxide short fibers; the reinforcing framework is aramid 1313 mesh cloth, aramid 1414 mesh cloth, quartz fiber mesh cloth, glass fiber mesh cloth or alumina fiber mesh cloth; the oxide short fibers are silica nanofibers or alumina nanofibers; the single-filament diameter of the oxide short fibers is 20-1000 nm, and the fiber length is 0.1 microns-2 mm. The preparation method comprises the following steps: short fiber slurry preparation; reinforcing framework surface treatment; and composite felt preparation. The composite felt prepared by the present application has the characteristics of high-temperature resistance, water resistance, lightness, thinness and high strength; the reinforcing framework has a protective effect on the oxide fibers, thereby prolonging the service life of the composite felt; the reinforcing framework improves the strength of the oxide fibers, so that the composite felt can be applied to various special-shaped structures.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of non-woven materials, and particularly relates to a high-temperature-resistant high-strength composite felt and a preparation method thereof. BACKGROUND

[0002] High-temperature insulation materials are a kind of materials that are resistant to high temperature, low thermal conductivity, flame-retardant, and can slow down heat loss, and are widely used in aerospace, industrial furnaces, high-temperature fuel cells, military fire fighting, metallurgy, pipelines and thermal equipment fields. With the development of science and technology, people's requirements for high-temperature insulation materials are increasing, and traditional high-temperature insulation materials have not met the needs. Commonly used fibrous insulation materials include asbestos, mullite, aluminum silicate and alumina fiber, etc. Fibrous insulation material is a kind of insulation material made of one or several kinds of fibers, which has the advantages of high temperature resistance, stable performance, easy processing, etc., but the fiber felt has the characteristics of light weight, excellent fireproof and heat insulation performance. The existing high-temperature-resistant fiber felt is thick, which is difficult to apply in the field of textiles. Inorganic oxide short fibers are resistant to high temperature and have low thermal conductivity, but the fibers are short and cannot be carded into a web. Wet felting technology is one of the non-woven material forming technologies, and the fibers are uniformly dispersed in water during the preparation process, and the felt prepared has no penetrating fibers and high flatness. Inorganic oxide short fibers are reinforced by compounding with fibers, and a certain mechanical strength and light and thin oxide composite felt is obtained by using wet felting technology, so as to meet the actual application requirements in the field of textiles.

[0003] A continuous alumina fiber preparation method is disclosed in Chinese patent No. CN202111329746.3, which uses a "sol-gel" method to prepare continuous alumina crystal fibers. Specifically, 5-7 MPa high-pressure air is used to boost the sol and form alumina fiber filaments through the spinning hole, and then the alumina fiber filaments are calcined at 1100-1400℃, and then drawn, wound and rolled to form continuous alumina fiber filaments. The invention uses a sol-gel method to spin and prepare alumina fiber filaments, which is suitable for fabrics, felts, fiber reinforced composites and the like, but still has the defect of insufficient internal friction between fibers.

[0004] A preparation method of a dense continuous alpha-alumina fiber material is disclosed in Chinese patent No. CN202210735011.9, which includes sol preparation, dry spinning and high-temperature calcination molding, so as to obtain continuous alpha-alumina filaments with alumina as the main crystal form. In the invention, mullite sol and zirconium sol are used to nucleate at a lower temperature, promote fiber formation and inhibit the growth of alpha-alumina grains during the sintering process. The invention also uses a sol-gel method to spin and prepare alpha-alumina fiber filaments with controllable crystal form, but still has the defect of complex preparation process.

[0005] A Chinese patent with the application number CN202211320347.5 discloses a low thermal conductivity fiber composite aerogel wet felt and its preparation method, which includes preparing a slurry, transporting and forming, and drying the gel to obtain a finished fiber composite aerogel wet felt. The invention combines the fiber felt making process with the aerogel composite process through specific process adjustment, shortens the preparation period, and reduces the manufacturing cost. The fiber composite aerogel wet felt prepared by the invention has the characteristics of low density and low thermal conductivity, but its performance is single and its application field is limited.

[0006] A Chinese patent with the application number CN201410767258.4 discloses a high-temperature-resistant wet felt and its preparation method. The thickness of the high-temperature-resistant wet felt is 6-22mm; the outer surface of the high-temperature-resistant wet felt is provided with a nano-silicon dioxide coating; and the outer surface of the fiber monofilament of the high-temperature-resistant wet felt is uniformly provided with closed vacuum spheres with a diameter of less than 20nm. The invention greatly reduces the thermal conductivity of the fiber cotton felt, does not add any binder, and has the characteristics of non-toxicity, high-temperature resistance, and low moisture absorption rate, but the product thickness is large and not light enough.

[0007] Therefore, in order to further improve the performance and application field of the oxide fiber felt, a high-performance composite felt is obtained by using oxide fiber composite materials. The present application proposes a high-temperature-resistant and high-strength composite felt and its preparation method. SUMMARY

[0008] The purpose of the present application is to solve the problems existing in the prior art and to provide a high-temperature-resistant and high-strength composite felt and its preparation method. The composite felt prepared by the present application has the characteristics of high-temperature resistance, waterproofness, lightness, and high strength, has a protective effect on oxide fibers, and prolongs the service life of the composite felt.

[0009] In order to achieve the above-mentioned purpose, the present application adopts the following technical scheme: a high-temperature-resistant and high-strength composite felt, which is composed of a reinforcing framework and oxide short fibers. The porosity of the high-temperature-resistant and high-strength composite felt is 70-99%, the density is 80-410kg / m 3 , the tear strength is 20-32cN / dtex, and the heat transfer coefficient at room temperature is 18-45W / (m 2 ·K).

[0010] Preferably, the reinforcing framework is aramid 1313 mesh cloth, aramid 1414 mesh cloth, quartz fiber mesh cloth, glass fiber mesh cloth, or alumina fiber mesh cloth; the areal density of the reinforcing framework is 80-150g / m 2 , the thickness is 0.1-0.5mm, and the mesh diameter is 0.5-5mm.

[0011] Preferably, the oxide short fibers are silica nanofibers or alumina nanofibers; the single-fiber diameter of the oxide short fibers is 20-1000 nm, and the fiber length is 0.1 μm-2 mm.

[0012] The application also provides a preparation method of the high-temperature-resistant high-strength composite felt, comprising the following steps:

[0013] S1, short fiber slurry preparation;

[0014] S2, aramid reinforced skeleton surface treatment;

[0015] S3, quartz, glass or alumina fiber reinforced skeleton surface treatment;

[0016] S4, preparation of the composite felt.

[0017] Preferably, in step S1, the following steps are specifically included:

[0018] S1.1, mixing oxide short fibers with water in a ratio of 250-300:1;

[0019] S1.2, adding a dispersant and a stabilizer to the water / fiber mixture of step S1.1 and uniformly dispersing;

[0020] S1.3, beating the mixture of step S1.2, the stirring speed being 500-600 rpm, and the beating time being 2-30 min.

[0021] Preferably, in step S2, the following steps are specifically included:

[0022] S2.1, placing the aramid reinforced skeleton in acetone and ultrasonically treating for 5-30 min to remove the surface glue;

[0023] S2.2, placing the aramid reinforced skeleton after removal of the surface glue in step S2.1 in anhydrous ethanol and ultrasonically treating for 5-20 min;

[0024] S2.3, drying the aramid reinforced skeleton after treatment in step S2.2 in an oven, the drying temperature being 40-60℃, and the drying time being 5-15 min.

[0025] Preferably, in step S3, the following steps are specifically included:

[0026] S3.1, placing the reinforced skeleton in a muffle furnace for high-temperature glue removal, the glue removal temperature being 300-600℃, and the glue removal time being 0.5-2 h;

[0027] S3.2, placing the reinforced skeleton after removal of the surface glue in step S3.1 in anhydrous ethanol and ultrasonically treating for 5-20 min;

[0028] S3.3, drying the reinforced framework treated in step S3.2 in an oven, the drying temperature is 40-60 DEG C, and the drying time is 5-15 min.

[0029] Preferably, in step S4, it specifically comprises the following steps:

[0030] S4.1, fixing the reinforced framework treated in step S2 or step S3 on a filter screen of a paper machine;

[0031] S4.2, conveying the fiber slurry prepared in step S1 to a pulp pool, and controlling the pulp flow rate to be 80-100 L / min;

[0032] S4.3, blowing air to stir the pulp in the pulp pool to make the pulp uniformly dispersed, and the blowing air stirring time is 15-30 s;

[0033] S4.4, rapidly dehydrating until the water in the pulp pool is drained, and a felt body is formed;

[0034] S4.5, dehydrating the felt body in step S4.4 under vacuum to obtain a composite felt on a forming screen, the dehydration negative pressure is 0.01-0.3 MPa, and the dehydration time is 10-60 s;

[0035] S4.6, drying the composite felt in step S4.5 in an oven to obtain a dried composite felt, the drying temperature is 80-150 DEG C, and the drying time is 0.5-5 h;

[0036] S4.7, spraying an organic silicon solution on the front and back surfaces of the dried composite felt in step S4.6, the solution concentration is 0.1-5%, and the spraying amount is 60-600 ml / m 2 ;

[0037] S4.8, drying the composite felt sprayed with the organic silicon solution in step S4.7 at 100-200 DEG C for 5-120 min to obtain a high-temperature-resistant and high-strength composite felt.

[0038] Compared with the prior art, the present application has the following beneficial effects:

[0039] 1. The present application uses the reinforced framework to improve the strength of the oxide fiber, so that the composite felt can be applied to various special-shaped structures.

[0040] 2. The present application uses the reinforced framework to protect the oxide fiber, thereby prolonging the service life of the composite felt.

[0041] 3. The composite felt prepared by the present application has the characteristics of high-temperature resistance, waterproof, lightness, and high strength. BRIEF DESCRIPTION OF DRAWINGS

[0042] Figure 1A structural schematic diagram of the silicon oxide aramid composite felt prepared for the embodiment 1 of the present application. DETAILED DESCRIPTION

[0043] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings, so that the persons skilled in the art can better understand the advantages and features of the present application, and the protection scope of the present application can be more clearly defined. The described embodiments of the present application are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments of the present application, all other embodiments obtained by the persons skilled in the art without creative labor fall within the protection scope of the present application.

[0044] Embodiment 1

[0045] A high-temperature-resistant and high-strength composite felt composed of a reinforcing framework and oxide short fibers;

[0046] The reinforcing framework is aramid 1313 mesh cloth, the thickness is 0.1 mm, and the mesh hole diameter is 5 mm.

[0047] The oxide short fibers are silicon oxide nanofibers, and the fiber monofilament diameter is 600 nm.

[0048] A preparation method of a high-temperature-resistant and high-strength composite felt, comprising the following steps:

[0049] S1, short fiber slurry preparation

[0050] S1.1, mixing silicon oxide fibers with water in a ratio of 250:1;

[0051] S1.2, adding a dispersing agent and a stabilizing agent to the water / fiber mixture of step S1.1 and uniformly dispersing;

[0052] S1.3, beating the mixture in step S1.2, the stirring speed is 500 rpm, and the beating time is 2 min;

[0053] S2, surface treatment of aramid reinforcing framework

[0054] S2.1, placing the reinforcing framework in acetone and ultrasonically treating for 10 min to remove the surface glue;

[0055] S2.2, placing the aramid reinforcing framework after removing the surface glue in step S2.1 in anhydrous ethanol and ultrasonically treating for 10 min;

[0056] S2.3, drying the aramid reinforcing framework after treatment in step S2.2 in an oven, the drying temperature is 50℃, and the drying time is 15 min;

[0057] S3, preparation of a composite felt

[0058] S3.1, fixing the reinforced framework treated in step S2 on the filter screen of the paper machine;

[0059] S3.2, delivering the fiber slurry prepared in step S1 to the pulp pool, and controlling the pulp flow rate to be 80 L / min;

[0060] S3.3, aerating and stirring the pulp in the pulp pool to make the pulp evenly dispersed, and the aeration and stirring time is 15 s;

[0061] S3.4, rapidly dewatering until the water in the pulp pool is drained and the felt body is formed;

[0062] S3.5, dewatering the felt body in step S3.4 under vacuum and preparing a composite felt on the forming wire, the dewatering negative pressure is 0.01 MPa, and the dewatering time is 40 s;

[0063] S3.6, drying the composite felt in step S3.5 in an oven to obtain a dried composite felt, the drying temperature is 120℃, and the drying time is 0.5 h;

[0064] S3.7, spraying an organic silicon solution on the front and back surfaces of the dried composite felt in step S3.6, the solution concentration is 5%, and the spraying amount is 200 ml / m 2 ;

[0065] S3.8, drying the composite felt sprayed with the organic silicon solution in step S3.7 at 180℃ for 30 min to obtain a high-temperature-resistant and high-strength composite felt.

[0066] The high-temperature-resistant and high-strength composite felt obtained in the embodiment has a heat transfer coefficient of 31.095 W / (m 2 ·K) at room temperature and a thermal conductivity of 0.034205 W / (m·K).

[0067] Example 2:

[0068] A high-temperature-resistant and high-strength composite felt composed of a reinforced framework and oxide short fibers;

[0069] The reinforced framework is aramid 1313 mesh cloth with a thickness of 0.1 mm and a mesh diameter of 5 mm.

[0070] The oxide short fibers are silica nanofibers with a fiber monofilament diameter of 600 nm.

[0071] A preparation method of a high-temperature-resistant and high-strength composite felt, comprising the following steps:

[0072] S1, short fiber slurry preparation

[0073] S1.1, mixing silica fibers with water in a ratio of 200:1;

[0074] S1.2, adding dispersant and stabilizer to the water / fiber mixture of step S1.1 and dispersing uniformly;

[0075] S1.3, beating the mixture of step S1.2, the stirring speed is 550 rpm, and the beating time is 3 min; the prepared slurry is 30 L.

[0076] S2, surface treatment of aramid reinforced framework

[0077] S2.1, placing the reinforced framework in acetone and ultrasonic treating for 15 min to remove the surface glue;

[0078] S2.2, placing the aramid reinforced framework after removing the surface glue in step S2.1 in anhydrous ethanol and ultrasonic treating for 15 min;

[0079] S2.3, drying the aramid reinforced framework after treatment in step S2.2 in an oven, the drying temperature is 50℃, and the drying time is 20 min.

[0080] S3, preparation of composite felt

[0081] S3.1, fixing the reinforced framework after surface treatment in step S2 on the filter screen of the paper machine;

[0082] S3.2, delivering the fiber slurry prepared in step S1 to the pulp pool, and controlling the slurry flow rate to be 90 L / min;

[0083] S3.3, air blowing to stir the slurry in the pulp pool to disperse the slurry uniformly, and the air blowing stirring time is 30 s;

[0084] S3.4, rapid dewatering until the water in the pulp pool is drained and the felt body is formed;

[0085] S3.5, dewatering the felt body in step S3.4 under vacuum and preparing the composite felt on the forming screen, the dewatering negative pressure is 0.01 MPa, and the dewatering time is 60 s;

[0086] S3.6, drying the composite felt in step S3.5 in an oven to obtain dried composite felt, the drying temperature is 120℃, and the drying time is 1 h;

[0087] S3.7, spraying silicone solution on the front and back surfaces of the dried composite felt in step S3.6, the solution concentration is 5%, and the spraying amount is 400 ml / m 2 ;

[0088] S3.8, drying the composite felt sprayed with silicone solution in step S3.7 at 180℃ for 30 min to prepare high-temperature-resistant and high-strength composite felt.

[0089] The heat transfer coefficient of the high-temperature-resistant and high-strength composite felt obtained in the embodiment is 25.61 W / (m 2 ·K) at room temperature, and the thermal conductivity is 0.03637 W / (m·K).

[0090] In summary, the composite felt prepared by the application has the characteristics of high-temperature resistance, waterproof, lightness, thinness and high strength; the reinforcing framework has a protective effect on the oxide fibers, prolonging the service life of the composite felt; the reinforcing framework improves the strength of the oxide fibers, so that the composite felt can be applied to various special-shaped structures.

[0091] The description and practice disclosed in the application are easy to think and understand for ordinary skilled in the art, and some improvements and refinements can be made without departing from the principles of the application. Therefore, the modifications or improvements made without departing from the spirit of the application should be considered as the protection scope of the application.

Claims

1. A high temperature resistant high strength composite mat, characterized in that, The high-temperature-resistant high-strength composite felt is mainly composed of a reinforcing framework and oxide short fibers, the reinforcing framework is aramid 1313 mesh cloth, aramid 1414 mesh cloth, quartz fiber mesh cloth, glass fiber mesh cloth or alumina fiber mesh cloth; the surface density of the reinforcing framework is 80-150 g / m 2 , the thickness is 0.1-0.5 mm, and the mesh diameter is 0.5-5 mm; the oxide short fibers are silica nanofibers or alumina nanofibers; the single-fiber diameter of the oxide short fibers is 20-1000 nm, and the fiber length is 0.1 μm-2 mm; the porosity of the high-temperature-resistant high-strength composite felt is 70-99%, the density is 80-410 kg / m 3 , the tear strength is 20-32 cN / dtex, and the heat transfer coefficient at room temperature is 18-45 W / (m 2 ·K).

2. A method for preparing a high temperature resistant high strength composite mat, characterized in that, The method comprises the following steps: S1, short fiber slurry preparation: S1.1, the oxide short fiber is mixed with water according to the proportion of 250~300:1; S1.2, adding dispersant and stabilizer to the water / fiber mixture of step S1.1 and uniformly dispersing; S1.3, the mixture in step S1.2 is beaten, the stirring speed is 500~600rpm, and the beating time is 2~30min; S2, aramid reinforced skeleton surface treatment: S2.1, the aramid reinforced skeleton is placed in acetone, and the surface glue is removed by ultrasonic treatment for 5~30min; S2.2, the aramid reinforced skeleton after removing the surface glue in step S2.1 is placed in anhydrous ethanol, and ultrasonic treatment is performed for 5~20min; S2.3, the aramid reinforced skeleton after treatment in step S2.2 is dried in an oven, the drying temperature is 40~60℃, and the drying time is 5~15min; S3, quartz, glass or alumina fiber reinforced skeleton surface treatment: S3.1, the reinforced skeleton is placed in a muffle furnace for high temperature glue removal, the glue removal temperature is 300~600℃, and the glue removal time is 0.5~2h; S3.2, the reinforced skeleton after removing the surface glue in step S3.1 is placed in anhydrous ethanol, and ultrasonic treatment is performed for 5~20min; S3.3, the reinforced skeleton after treatment in step S3.2 is dried in an oven, the drying temperature is 40~60℃, and the drying time is 5~15min; S4, preparation of composite felt: S4.1, the reinforced skeleton after surface treatment in step S2 or step S3 is fixed on the filter screen of the paper machine; S4.2, the fiber slurry prepared in step S1 is delivered to the pulp pool, and the slurry flow rate is controlled at 80~100 L / min; S4.3, air blowing is performed to stir the slurry in the pulp pool to uniformly disperse the slurry, and the air blowing stirring time is 15~30s; S4.4, rapid dewatering until the water in the pulp pool is completely discharged, and the felt body is formed; S4.5, the felt body in step S4.4 is dewatered under vacuum to obtain the composite felt on the forming screen, the dewatering negative pressure is 0.01~0.3MPa, and the dewatering time is 10~60s; S4.6, the composite felt in step S4.5 is dried in an oven to obtain the dried composite felt, the drying temperature is 80~150℃, and the drying time is 0.5~5h; S4.7, spray the front and back surfaces of the dried composite felt in step S4.6 with a silicone solution, the solution concentration is 0.1-5%, and the spraying amount is 60-600 mL / m 2 ; S4.8, the composite felt sprayed with the silicone solution in step S4.7 is dried at 100~200℃ for 5~120min to obtain the high-temperature-resistant and high-strength composite felt.

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