Preparation method of high-strength multilayer composite fabric

Abstract

The invention discloses a preparation method of a high-strength multilayer composite fabric, and relates to the technical field of textile fabrics. According to the method, 6, 6 '-dihydroxy-3, 3'-diphenyldicarboxylic acid and 4, 6-diamino resorcinol hydrochloride are polymerized, acrylic acid is added, the mixture and a polymer are subjected to dehydration and condensation, so that the interface bonding performance of a matrix is improved, a non-woven fabric is formed through spinning, then plasma and hot-pressing treatment is conducted in sequence, plasma discharge is conducted, and the surface of the non-woven fabric is coated with a coating. Meanwhile, when the high-energy particles impact fibers, a large number of concave-convex structures are formed on the surfaces of the fibers, the bonding performance between interfaces is greatly improved, then the high-energy particles are compounded on the two faces of the aramid fiber fabric, and the mechanical embedding effect between the film layer and the fabric is enhanced through hot pressing treatment; then the other side of the non-woven fabric is coated with the surface finishing agent, so that the protective layer is formed, and the zirconium boride particles in the protective layer can make the fiber texture tighter, so that the strength of the composite fabric is greatly improved.

Description

Technical Field

[0001] The present invention relates to the technical field of textile fabrics, and specifically to a preparation method of a high-strength multi-layer composite fabric. Background Art

[0002] With the improvement of the social industrialization level, textiles no longer exist only to meet their wearing value. Different industries have different demands for textiles, and functional textiles have emerged as the times require. For example, spacesuits must ensure radiation protection, heat preservation, and airtightness while satisfying the movement of astronauts; maternity clothes must be mite-proof, self-cleaning, and radiation-proof; fire-fighting suits need to be flame-retardant, wear-resistant, and waterproof to meet the work requirements of firefighters. In the textile manufacturing field where quality is of utmost importance, ensuring the integrity and durability of fabrics is an essential aspect; textiles often withstand various stresses during their life cycle, including tension, pulling force, and pressure. Fabrics with higher strength are more durable and can withstand these stresses without tearing or breaking, thus ensuring service life and performance.

[0003] Even in the fast-paced fashion industry where trends come and go, durability is an eternal attribute. Clothing with high strength can better withstand the harsh tests of daily wear and tear, ensuring service life and customer satisfaction. From jeans to sportswear to underwear, burst strength testing plays a crucial role in providing clothing that can stand the test of time. In the field of healthcare, sterility and patient safety are of utmost importance, and medical textiles are rigorously tested to ensure their efficacy and integrity. Burst strength testing of surgical gowns, surgical drapes, and wound dressings ensures that these critical materials can withstand the stresses of sterilization and use, providing assurance for healthcare professionals and patients, etc. Summary of the Invention

[0004] The purpose of the present invention is to provide a preparation method of a high-strength multi-layer composite fabric to solve the problems existing in the prior art.

[0005] To solve the above technical problems, the present invention provides the following technical solution: A preparation method of a high-strength multi-layer composite fabric, including the following preparation steps:

[0006] (1) Mix 6,6'-dihydroxy-3,3'-biphenyldicarboxylic acid, 4,6-diaminoresorcinol hydrochloride, terephthalic acid, and an 85 wt% polyphosphoric acid aqueous solution, heat to 100 - 140 °C under a nitrogen atmosphere, stir at 100 - 200 rpm for 90 - 140 min, add acrylic acid, heat to 180 - 220 °C at a rate of 5 - 13 °C / h, continue to stir for 30 - 50 min, carry out melt spinning, wash with water, and then dry at 80 - 120 °C and a vacuum degree of 0.2 - 1 kPa for 2 - 4 h, and then card and form a web and needle-punch for reinforcement, with a needle-punch density of 3.2 needles / cm 2, with a depth of 5 mm, to obtain a non-woven fabric;

[0007] (2) Subject the non-woven fabric to plasma treatment, then laminate it on both the upper and lower surfaces of the aramid fabric, and perform hot pressing treatment to obtain a composite fabric;

[0008] (3) Coat the surface finishing agent on both the upper and lower surfaces of the composite fabric and dry it to obtain a high-strength multi-layer composite fabric.

[0009] Further, the acrylic acid described in step (1) is specifically acrylic resin BR-116.

[0010] Further, the process parameters of the melt spinning in step (1): the temperature is 250 °C and the speed is 1500 m / min.

[0011] Further, the mass ratio of 6,6'-dihydroxy-3,3'-biphenyldicarboxylic acid, 4,6-diaminoresorcinol hydrochloride, terephthalic acid, 85 wt% polyphosphoric acid aqueous solution, and acrylic acid in step (1) is 0.5 - 2:2 - 5:0.4:10 - 20:0.05 - 0.3.

[0012] Further, the process parameters of the plasma treatment in step (2): the discharge power density is 30 W / cm 3 and the time is 10 - 20 s.

[0013] Further, the gram weight of the aramid fabric in step (2) is 120 - 200 g / m 2 .

[0014] Further, the temperature of the hot pressing treatment in step (2) is 100 - 130 °C, the pressure is 0.1 - 1 MPa, and the time is 15 - 60 s.

[0015] Further, the preparation method of the surface finishing agent in step (3): Mix aqueous polyurethane AH-1704-1 and epoxy resin E51 in a mass ratio of 10:0.5 - 1, heat up to 30 - 50 °C, stir at 1200 - 1800 rpm for 20 - 40 min, add a thickener of BASF RHEOVIS PU 1191 with a mass 0.2 - 0.5 times that of epoxy resin E51 and a zirconium boride powder with a mass 0.5 - 0.9 times that of epoxy resin E51, continue to stir for 10 min, and perform two oscillations, each for 3 min, to obtain it.

[0016] Further, the dosage of the surface finishing agent in step (3) is 80 - 150 g / m 2 .

[0017] Further, the drying temperature in step (3) is 60 - 90 °C and the time is 5 - 8 h.

[0018] Compared with the prior art, the beneficial effects achieved by the present invention are as follows:

[0019] The fabric of the present invention is prepared by a structure of protective layer - adhesion layer - reinforcing layer - adhesion layer - protective layer to achieve the effect of high mechanical properties.

[0020] First, 6,6'-dihydroxy-3,3'-biphenyldicarboxylic acid is polymerized with 4,6-diaminoresorcinol hydrochloride through its carboxyl group. At the same time, the hydroxyl group on the benzene ring in 4,6-diaminoresorcinol hydrochloride undergoes a hydrogen bond association with the nitrogen element on the adjacent oxazole ring, introducing the hydroxyl group in 6,6'-dihydroxy-3,3'-biphenyldicarboxylic acid into the polymer molecule, enhancing the interaction between macromolecular chains, and thus obtaining modified poly(p-phenylene benzobisoxazole). With the increase in the number of hydroxyl groups and branches, the polarity and wettability of the matrix are significantly improved. During the copolymerization process, acrylic acid is added and undergoes dehydration and condensation with the hydroxyl groups on the polymer, thereby improving the interfacial bonding performance of the composite material. Then, it is spun into a non-woven fabric, and then successively subjected to plasma and hot pressing treatments. During plasma discharge, a large number of high-energy particles such as electrons, photons, and ions in the air are sputtered, causing the benzene rings and oxazole rings on the surface of the matrix fibers to break. The oxygen-containing and nitrogen-containing active particles in the plasma can compensate for the amount of the original groups that are damaged at this time, further increasing the content of polar groups. At the same time, when these high-energy particles impact the fibers, free radical fragments are formed on the fiber surface molecules, and they undergo bonding to form a cross-linked layer on the fiber surface, and cause sputtering and erosion of the fiber surface. Due to the difference in crystal regions and amorphous regions in the structure of each part of the matrix, a large number of uneven structures are formed on the fiber surface, greatly improving the bonding performance between the interfaces.

[0021] Secondly, the non-woven fabric is used as the adhesion layer and compounded on both sides of the aramid fabric. Under high temperature and high pressure conditions, the movement of acrylic acid is accelerated and gradually penetrates into the gaps of the aramid fabric, enhancing the mechanical interlocking effect between the film layer and the fabric, thereby enhancing the mechanical properties of the composite fabric. Then, through the rough surface of the fibers in the non-woven fabric, a physical fit is formed with the polymer in the surface finishing agent to form a protective layer, and the cohesion between the fibers can be increased. Zirconium boride particles are added and embedded between the fibers of the non-woven fabric to make the structure more compact, thereby reducing relative sliding and further improving the strength of the composite fabric. Specific embodiments

[0022] Next, in combination with the embodiments of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts fall within the scope of protection of the present invention.

[0023] To illustrate the method provided by the present invention more clearly, the following embodiments are used for detailed description. The test methods for various indexes of the high-strength multi-layer composite fabric produced in the following embodiments are as follows:

[0024] Mechanical properties: Take the same size of the examples and comparative examples, and refer to GB / T529, DIN53273, and GB / T21196.3 respectively to test the tear strength, peel strength, and mass loss rate of the fabric.

[0025] Example 1; (1) Mix 6,6'-dihydroxy-3,3'-biphenyldicarboxylic acid, 4,6-diaminoresorcinol hydrochloride, terephthalic acid, and 85wt% polyphosphoric acid aqueous solution, and under a nitrogen atmosphere, heat up to 100°C, stir at 100 rpm for 90 min, add acrylic resin BR-116, heat up to 180°C at a rate of 5°C / h, and continue to stir for 30 min, and then carry out melt spinning. The process parameters are: temperature is 250°C, speed is 1500 m / min. After washing with water, then dry at 80°C and a vacuum degree of 0.2 kPa for 2 h, and then card into a web and needle-punched for reinforcement. The needle-punching density is 3.2 needles / cm 2 and the depth is 5 mm to obtain a non-woven fabric; the mass ratio of 6,6'-dihydroxy-3,3'-biphenyldicarboxylic acid, 4,6-diaminoresorcinol hydrochloride, terephthalic acid, 85wt% polyphosphoric acid aqueous solution, and acrylic resin BR-116 is 0.5:2:0.4:10:0.05.

[0026] (2) Treat the non-woven fabric by plasma. The process parameters are: the discharge power density is 30 W / cm 3 and the time is 10 s, and then compound it on the upper and lower surfaces of an aramid fabric with a gram weight of 120 g / m 2 , and under the conditions of 100°C and a pressure of 0.1 MPa, carry out hot pressing treatment for 15 s to obtain a composite fabric;

[0027] (3) Mix aqueous polyurethane AH-1704-1 and epoxy resin E51 in a mass ratio of 10:0.5, heat up to 30°C, stir at 1200 rpm for 20 min, add a BASF RHEOVIS PU 1191 thickener 0.2 times the mass of epoxy resin E51 and a zirconium boride powder 0.5 times the mass of epoxy resin E51, continue to stir for 10 min, and carry out two oscillations, each for 3 min, to obtain a surface finishing agent; coat the surface finishing agent on the upper and lower surfaces of the composite fabric at 80 g / m 2 , and dry at 60°C for 5 h to obtain a high-strength multi-layer composite fabric.

[0028] Example 2; (1) Mix 6,6'-dihydroxy-3,3'-biphenyldicarboxylic acid, 4,6-diaminoresorcinol hydrochloride, terephthalic acid, and 85 wt% polyphosphoric acid aqueous solution. Under a nitrogen atmosphere, heat up to 110°C and stir at 180 rpm for 120 min. Add acrylic resin BR-116, and heat up to 200°C at a rate of 10°C / h, continue stirring for 40 min, and perform melt spinning. The process parameters are: temperature 250°C, speed 1500 m / min. After washing with water, then dry at 110°C and a vacuum of 0.6 kPa for 3 h, and then card into a web and needle-punch for reinforcement. The needle-punch density is 3.2 needles / cm 2 , and the depth is 5 mm to obtain a non-woven fabric; the mass ratio of 6,6'-dihydroxy-3,3'-biphenyldicarboxylic acid, 4,6-diaminoresorcinol hydrochloride, terephthalic acid, 85 wt% polyphosphoric acid aqueous solution, and acrylic resin BR-116 is 1.3:3.5:0.4:15:0.2.

[0029] (2) Treat the non-woven fabric by plasma. The process parameters are: discharge power density 30 W / cm 3 and time 15 s, and then laminate it on the upper and lower surfaces of an aramid fabric with a grammage of 160 g / m 2 . Then, under the conditions of 100°C and a pressure of 0.6 MPa, perform hot pressing for 40 s to obtain a composite fabric;

[0030] (3) Mix aqueous polyurethane AH-1704-1 and epoxy resin E51 in a mass ratio of 10:0.75, heat up to 40°C, stir at 1500 rpm for 30 min, add a BASF RHEOVIS PU 1191 thickener that is 0.3 times the mass of epoxy resin E51 and a zirconium boride powder that is 0.7 times the mass of epoxy resin E51, continue stirring for 10 min, and perform two oscillations, each for 3 min, to obtain a surface finishing agent. Coat the surface finishing agent on the upper and lower surfaces of the composite fabric at 120 g / m 2 , and dry at 70°C for 6 h to obtain a high-strength multi-layer composite fabric.

[0031] Example 3; (1) Mix 6,6'-dihydroxy-3,3'-biphenyldicarboxylic acid, 4,6-diaminoresorcinol hydrochloride, terephthalic acid, and 85 wt% polyphosphoric acid aqueous solution. Under a nitrogen atmosphere, heat up to 140°C and stir at 200 rpm for 140 min. Add acrylic resin BR-116, and heat up to 220°C at a rate of 13°C / h, continue stirring for 50 min, and perform melt spinning. The process parameters are: temperature 250°C, speed 1500 m / min. After washing with water, then dry at 120°C and a vacuum of 1 kPa for 4 h, and then card into a web and needle-punch for reinforcement. The needle-punch density is 3.2 needles / cm 2, with a depth of 5 mm, to obtain a non-woven fabric; the mass ratio of 6,6'-dihydroxy-3,3'-biphenyldicarboxylic acid, 4,6-diaminoresorcinol hydrochloride, terephthalic acid, 85 wt% polyphosphoric acid aqueous solution, and acrylic resin BR-116 is 2:5:0.4:20:0.3.

[0032] (2) The non-woven fabric is treated by plasma, and its process parameters: the discharge power density is 30 W / cm 3 , the time is 20 s, and then it is laminated on the upper and lower surfaces of an aramid fabric with a grammage of 200 g / m 2 , and under the conditions of 130 °C and a pressure of 1 MPa, hot pressing treatment is carried out for 60 s to obtain a composite fabric;

[0033] (3) Mix aqueous polyurethane AH-1704-1 and epoxy resin E51 in a mass ratio of 10:1, heat up to 50 °C, stir at 1800 rpm for 40 min, add a BASF RHEOVIS PU 1191 thickener that is 0.5 times the mass of epoxy resin E51 and zirconium boride powder that is 0.9 times the mass of epoxy resin E51, continue to stir for 10 min, and perform two oscillations, each for 3 min, to obtain a surface finishing agent; coat the surface finishing agent on the upper and lower surfaces of the composite fabric at 150 g / m 2 , and dry it at 90 °C for 8 h to obtain a high-strength multi-layer composite fabric.

[0034] Comparative Example 1; The difference between Comparative Example 1 and Example 2 lies in step (1). Step (1) is changed to: Mix 4,6-diaminoresorcinol hydrochloride, terephthalic acid, and 85 wt% polyphosphoric acid aqueous solution, under a nitrogen atmosphere, heat up to 110 °C, stir at 180 rpm for 120 min, add acrylic resin BR-116, heat up to 200 °C at 10 °C / h, continue to stir for 40 min, and perform melt spinning. Its process parameters: the temperature is 250 °C, the speed is 1500 m / min, wash with water, and then dry at 110 °C and a vacuum degree of 0.6 kPa for 3 h, card into a web, and needle-punch for reinforcement. The needle-punch density is 3.2 needles / cm 2 , with a depth of 5 mm, to obtain a non-woven fabric; the mass ratio of 4,6-diaminoresorcinol hydrochloride, terephthalic acid, 85 wt% polyphosphoric acid aqueous solution, and acrylic resin BR-116 is 3.5:0.4:15:0.2; the remaining steps are the same as in Example 2.

[0035] Comparative Example 2; The difference between Comparative Example 2 and Example 2 lies in step (1). Step (1) is modified as follows: 6,6'-dihydroxy-3,3'-biphenyldicarboxylic acid, 4,6-diaminoresorcinol hydrochloride, terephthalic acid, and 85 wt% polyphosphoric acid aqueous solution are mixed. Under a nitrogen atmosphere, the temperature is raised to 110°C, and stirring is carried out at 180 rpm for 120 min. Then the temperature is raised to 200°C at a rate of 10°C / h, and stirring is continued for 40 min. Melt spinning is carried out with process parameters: temperature of 250°C and speed of 1500 m / min. After washing with water, it is then dried at 110°C and a vacuum degree of 0.6 kPa for 3 h, and then carded into a web and needle-punched for reinforcement. The needle-punching density is 3.2 needles / cm 2 and a depth of 5 mm to obtain a nonwoven fabric; The mass ratio of 6,6'-dihydroxy-3,3'-biphenyldicarboxylic acid, 4,6-diaminoresorcinol hydrochloride, terephthalic acid, and 85 wt% polyphosphoric acid aqueous solution is 1.3:3.5:0.4:15; The remaining steps are the same as those in Example 2.

[0036] Comparative Example 3; The difference between Comparative Example 3 and Example 2 lies in step (2). Step (2) is modified as follows: The nonwoven fabric is laminated on the upper and lower surfaces of an aramid fabric with a grammage of 160 g / m 2 and heat-pressed at 100°C and a pressure of 0.6 MPa for 40 s to obtain a composite fabric; The remaining steps are the same as those in Example 2.

[0037] Comparative Example 4; The difference between Comparative Example 4 and Example 2 lies in step (2). Step (2) is modified as follows: The nonwoven fabric is treated by plasma with process parameters: discharge power density of 30 W / cm 3 and a time of 15 s, and then laminated on the upper and lower surfaces of an aramid fabric with a grammage of 160 g / m 2 to obtain a composite fabric; The remaining steps are the same as those in Example 2.

[0038] Comparative Example 5; The difference between Comparative Example 5 and Example 2 lies in step (3). Step (3) is modified as follows: Waterborne polyurethane AH-1704-1 and epoxy resin E51 are mixed in a mass ratio of 10:0.75, the temperature is raised to 40°C, and stirring is carried out at 1500 rpm for 30 min. Then a BASF RHEOVIS PU 1191 thickener 0.3 times the mass of the epoxy resin E51 is added, and stirring is continued for 10 min, and two oscillations are carried out, each for 3 min, to obtain a surface finishing agent; The surface finishing agent is coated on the upper and lower surfaces of the composite fabric at 120 g / m 2 and dried at 70°C for 6 h to obtain a high-strength multi-layer composite fabric; The remaining steps are the same as those in Example 2.

[0039] Comparative Example 6; The difference between Comparative Example 6 and Example 2 is that step (3) is absent; The remaining steps are the same as those in Example 2.

[0040] Effect example

[0041] The following Table 1 shows the performance analysis results of the high-strength multi-layer composite fabrics using Examples 1 to 3 and Comparative Examples 1 to 6 of the present invention.

[0042] Table 1

[0043] <![CDATA[Tear strength (kg / cm 2 )]]> Peeling strength (kg / cm) Mass loss rate (15000r, %) Example 1 6.9 7.3 3.14 Example 2 7.2 7.9 3.05 Example 3 6.8 7.6 3.10 Comparative Example 1 6.2 7.1 3.19 Comparative Example 2 6.5 5.2 3.56 Comparative Example 3 6.4 5.3 3.52 Comparative Example 4 6.3 5.5 3.47 Comparative Example 5 5.7 6.6 4.81 Comparative Example 6 5.1 6.4 5.33

[0044] From the comparison of the experimental data of the examples and comparative examples in Table 1, it can be found that 6,6'-dihydroxy-3,3'-biphenyldicarboxylic acid polymerizes with 4,6-diaminoresorcinol hydrochloride through its carboxyl group, and at the same time, the hydroxyl group on the benzene ring in 4,6-diaminoresorcinol hydrochloride forms a hydrogen bond association with the nitrogen element on the adjacent oxazole ring, so that the hydroxyl group in 6,6'-dihydroxy-3,3'-biphenyldicarboxylic acid is introduced into the polymer molecule, enhancing the interaction between macromolecular chains, thereby obtaining modified poly(p-phenylene benzobisoxazole). And with the increase of the number of hydroxyl groups and branches, the polarity and wettability of the matrix are significantly improved. Acrylic acid is added during the copolymerization process and undergoes dehydration and condensation with the hydroxyl groups on the polymer, thereby improving the interfacial bonding performance of the composite material. Then, it is spun into a non-woven fabric, and then subjected to plasma and hot pressing treatments in sequence. Through the plasma discharge treatment, the benzene ring and oxazole ring on the surface of the matrix fiber are broken, and the oxygen-containing and nitrogen-containing active particles in the plasma can make up for the amount of the original groups that have been damaged, thereby further increasing the content of polar groups. At the same time, when these high-energy particles impact the fiber, the surface molecules of the fiber form free radical fragments, forming a cross-linked layer on the surface of the fiber and forming a large number of uneven structures, greatly improving the bonding performance between the interfaces. Then, the non-woven fabric is used as an adhesion layer and compounded on both sides of the aramid fabric. Under high temperature and high pressure conditions, the movement of acrylic acid is accelerated and gradually penetrates into the gaps of the aramid fabric, enhancing the mechanical interlocking effect between the film layer and the fabric. Then, through the rough surface of the fibers in the non-woven fabric, a physical fit is formed with the polymer in the surface finishing agent, and the bonding force between the fibers can be increased. Zirconium boride particles are added and embedded between the fibers of the non-woven fabric to make the structure more compact, further improving the strength of the composite fabric.

[0045] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and without departing from the spirit or basic characteristics of the present invention, the present invention can be implemented in other specific forms. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present invention. Any reference signs in the claims should not be regarded as limiting the claimed rights.

Claims

1. A method for preparing a high-strength multi-layer composite fabric, characterized in that: The method comprises the following preparation steps: (1) 6,6'-dihydroxy-3,3'-biphenyldicarboxylic acid, 4,6-diaminoresorcinol hydrochloride, terephthalic acid, and 85 wt% polyphosphoric acid aqueous solution are mixed, heated to 100-140° C. in a nitrogen atmosphere, and stirred at 100-200 rpm for 90-140 min. Acrylic acid is added, and the temperature is raised to 180-220° C. at 5-13° C. / h. Stirring is continued for 30-50 min, and melt spinning is performed. The mixture is washed with water, and then dried at 80-120° C. and a vacuum degree of 0.2-1 kPa for 2-4 h. The mixture is carded into a web, and needle punched to reinforce the web. The needle punching density is 3.2 thorns / cm 2 , the depth is 5 mm, and a nonwoven fabric is obtained; (2) treating the nonwoven fabric with plasma, and then compounding it with the upper and lower surfaces of the aramid fabric, and performing heat pressing to obtain a composite fabric; (3) Applying a surface finishing agent to the upper and lower surfaces of the composite fabric and drying the composite fabric to obtain a high-strength multi-layer composite fabric.

2. The method for preparing a high-strength multi-layer composite fabric according to claim 1, characterized in that: The acrylic acid in step (1) is specifically acrylic resin BR-116.

3. The method for preparing a high-strength multi-layer composite fabric according to claim 1, characterized in that: The process parameters of the melt spinning in step (1) are: temperature of 250° C. and speed of 1500 m / min.

4. The method for preparing a high-strength multi-layer composite fabric according to claim 1, characterized in that: In step (1), the mass ratio of 6,6'-dihydroxy-3,3'-biphenyldicarboxylic acid, 4,6-diaminoresorcinol hydrochloride, terephthalic acid, 85wt% polyphosphoric acid aqueous solution, and acrylic acid is 0.5-2:2-5:0.4:10-20:0.05-0.

3.

5. The method for preparing a high-strength multi-layer composite fabric according to claim 1, characterized in that: The process parameters of the plasma treatment in step (2) are as follows: the discharge power density is 30 W / cm 3 , time is 10 to 20 seconds.

6. The method for preparing a high-strength multi-layer composite fabric according to claim 1, characterized in that: The aramid fabric in step (2) has a gram weight of 120 to 200 g / m 2 .

7. The method for preparing a high-strength multi-layer composite fabric according to claim 1, characterized in that: The temperature of the hot pressing treatment in step (2) is 100-130° C., the pressure is 0.1-1 MPa, and the time is 15-60 seconds.

8. The method for preparing a high-strength multi-layer composite fabric according to claim 1, characterized in that: The preparation method of the surface finishing agent in step (3) is as follows: water-based polyurethane AH-1704-1 and epoxy resin E51 are mixed in a mass ratio of 10:0.5-1, the temperature is raised to 30-50° C., and the mixture is stirred at 1200-1800 rpm for 20-40 min. BASF RHEOVIS PU 1191 thickener in an amount of 0.2-0.5 times the mass of epoxy resin E51 and zirconium boride powder in an amount of 0.5-0.9 times the mass of epoxy resin E51 are added, the mixture is stirred for 10 min, and the mixture is shaken twice, each time for 3 min, to obtain the surface finishing agent.

9. The method for preparing a high-strength multi-layer composite fabric according to claim 1, characterized in that: The amount of the surface finishing agent in step (3) is 80-150 g / m 2 .

10. The method for preparing a high-strength multi-layer composite fabric according to claim 1, characterized in that: The drying temperature in step (3) is 60-90° C. and the drying time is 5-8 hours.