Method for preparing thickening fiber for flexible protective material

Abstract

The present invention relates to the technical field of composite materials, and more particularly to a method for preparing thickening fibers for flexible protective materials. The method for preparing thickening fibers for flexible protective materials of the present invention comprises the following steps: (1) modifying halloysite nanotubes, (2) preparing a composite shear thickening liquid, (3) preparing a core layer solution, (4) preparing a sheath protective layer solution, and (5) preparing flexible thickening fibers. The present invention provides a thickening fiber for flexible protective materials, wherein the thickening fiber is modified to enhance the interaction between the halloysite and polyvinyl alcohol, thereby improving the protective properties and flexibility of a protective fabric prepared from the thickening fiber.

Description

Technical Field

[0001] The present invention relates to the technical field of composite materials, and in particular to a method for preparing thickening fibers for flexible protective materials. Background Art

[0002] Shear thickening liquid is a non-Newtonian liquid. When a certain external force is applied, its viscosity increases dramatically, and it quickly transforms from a liquid state to a solid state to resist high-speed impact. When the impact force disappears, a reversible phase change occurs and it returns to a liquid state. The existing technology often directly immerses fiber fabrics in shear thickening liquids to form thickened fabrics, which can greatly improve the protectiveness. However, since shear thickening liquids contain high concentrations of inorganic fillers, directly immersing the fabric in shear thickening liquids will cause the inorganic fillers therein to be unevenly distributed on the fabric surface, forming more agglomerates, affecting the flexibility of the fiber fabric. Moreover, as the use time increases, the inorganic particles impregnated on the fabric surface will continue to fall off, affecting the protectiveness of the fiber fabric. Summary of the Invention

[0003] In view of this, the purpose of the present invention is to propose a method for preparing thickening fibers for flexible protective materials to solve the problems of decreased flexibility of fiber fabrics and shedding of inorganic particles on the fabric surface caused by directly immersing the fiber fabrics in a shear thickening liquid.

[0004] Based on the above objectives, the present invention provides a method for preparing thickening fibers for flexible protective materials. The specific preparation method is as follows:

[0005] (1) washing the halloysite nanotubes with deionized water, filtering, and repeating the process several times, then drying at 60-100° C., adding the nanotubes to anhydrous ethanol, mixing evenly, and then adding tetraethyl orthosilicate and heptafluorodecyltrimethoxysilane dropwise. After the addition is complete, adjusting the pH to 8-9 with ammonia water, and then reacting at room temperature for 4-6 hours, centrifuging, washing, and drying to obtain modified halloysite tubes;

[0006] (2) mixing the silane coupling agent and polyvinyl alcohol and stirring them uniformly, then adding nano-silica and modified halloysite tubes, and alternately stirring and ultrasonically shaking until the nano-silica particles are uniformly dispersed to obtain a composite shear thickening liquid;

[0007] (3) The composite shear thickening liquid and anhydrous ethanol are mixed and stirred evenly, left for 10-14 hours to remove bubbles, and then injected into a syringe as the core layer solution;

[0008] (4) After mixing nylon and formic acid, add them to a magnetic stirrer to disperse them evenly, and then inject them into a syringe to serve as a sheath protective layer solution;

[0009] (5) The syringes containing the core layer solution and the sheath protective layer solution are placed in a spinning machine and pushed forward simultaneously at a propulsion speed ratio of 1:2. The solutions ejected from the two syringes enter the same tube. The electrospinning method is adopted. The coaxial nozzle is composed of two concentric stainless steel needles. A core-sheath structure is formed in the tube, and then it is directly pressurized and ejected to form a thickening fiber for a flexible protective material with a core-sheath structure.

[0010] Preferably, in step (1), the radial width of the halloysite nanotubes is 50-100 nm, and the radial ratio is 10-20.

[0011] Preferably, in step (1), the weight ratio of halloysite nanotubes, anhydrous ethanol, tetraethyl orthosilicate and heptadecafluorodecyltrimethoxysilane is 1-5:10-30:0.2-1:0.01-0.1.

[0012] Preferably, the average particle size of the nano-silicon dioxide in step (2) is 400-500 nm.

[0013] Preferably, the silane coupling agent in step (2) is silane coupling agent A-1120.

[0014] Preferably, the weight proportions of the raw materials in step (2) are 20-80 parts of nano-silicon dioxide, 60-100 parts of polyvinyl alcohol, 0.2-1 parts of silane coupling agent, and 1-5 parts of modified halloysite tube.

[0015] Preferably, the weight proportions of the raw materials in step (3) are 80-120 parts of the composite shear thickening liquid and 80-120 parts of anhydrous ethanol.

[0016] Preferably, the mass fraction ratio of the nylon solution in the step (3) is 10%-15%, the mixing magnetic stirring time is 100 minutes, and the stirring temperature is 65°C.

[0017] Preferably, the parameters of the spinning machine in step (4) are positive pressure 14.5kv, negative pressure -9.5kv; the pushing speed is 0.25-0.3ml / h, the roller speed is 100rpm; the scanning starting point is 200mm, the scanning stroke is 10-30mm, the scanning speed is 10-15mm / s, the outdoor temperature and humidity are (28°C, 72%), and the temperature inside the machine is (26.7°C, 54%).

[0018] Preferably, in step (4), the two concentric stainless steel needles have an inner needle with an outer diameter of 0.41 mm (22 gauge) and an outer needle with an inner diameter of 1.01 mm (17 gauge).

[0019] Furthermore, the present invention also provides a flexible protective fabric, which is woven from the above-mentioned flexible protective material using thickening fibers.

[0020] The surface density of the flexible protective fabric is 120-140 g / m 2 .

[0021] Beneficial effects of the present invention:

[0022] (1) The flexible protective material prepared from the flexible thickening fiber with a core-sheath structure prepared in the present invention has good flexibility, is not easy to break or deform, and has excellent protective performance.

[0023] (2) The present invention uses a composite shear thickening liquid and anhydrous ethanol as a core layer solution and a nylon solution as a sheath protective layer solution to obtain a flexible thickening fiber with a core-sheath structure through electrospinning, which is then woven into a fabric. Compared with the prior art of directly impregnating the fabric, the present invention facilitates the uniform dispersion of the nanoparticles in the shear thickening liquid on the fabric, and can also coat the thickening shear liquid inside the fiber, thereby further enhancing its protective performance.

[0024] (3) The addition of the modified halloysite tubes in the present invention can reduce the critical shear rate and the maximum viscosity shear rate of the shear thickening fluid, and increase the viscosity corresponding to the maximum viscosity shear rate, which helps to improve the protectiveness of the fiber fabric. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 3 and 4 are the viscosity-shear rate curves of the shear thickening fluids provided in Example 3 and Comparative Example 4 of the present invention. DETAILED DESCRIPTION

[0026] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to specific embodiments.

[0027] Example 1: A method for preparing thickening fibers for flexible protective materials, the specific preparation steps are as follows:

[0028] (1) 1 g of halloysite nanotubes was washed with deionized water, filtered, and repeated several times, and then dried at 60°C. The halloysite nanotubes were then added to 10 g of anhydrous ethanol and mixed evenly. 0.2 g of tetraethyl orthosilicate and 0.01 g of heptadecafluorodecyltrimethoxysilane were then added dropwise. After the addition was complete, the pH was adjusted to 8-9 using aqueous ammonia, and the mixture was reacted at room temperature for 4 h. The mixture was centrifuged, washed, and dried to obtain modified halloysite tubes.

[0029] (2) 0.2 parts of silane coupling agent A-1120 and 60 parts of polyvinyl alcohol were mixed and stirred uniformly, and then 20 parts of nano-silica with an average particle size of 400 nm and 1 part of modified halloysite tube were added, and stirring and ultrasonic vibration were alternately performed until the nano-silica particles were uniformly dispersed to obtain a composite shear thickening liquid;

[0030] (3) 80 parts of the composite shear thickening fluid and 80 parts of anhydrous ethanol were mixed evenly, allowed to stand for 12 hours to remove bubbles, and then injected into a syringe as the core layer solution;

[0031] (4) 20 g of formic acid and 2.22 g of nylon were mixed and added to a magnetic stirrer. The stirring time was 100 min and the stirring temperature was 65°C.

[0032] (5) The syringes containing the core layer solution and the sheath protective layer solution were placed in the spinning machine and pushed forward simultaneously at a propulsion speed ratio of 1:2. The solutions ejected from the two syringes entered the same tube. The coaxial nozzle consisted of two concentric stainless steel needles, wherein the inner needle had an outer diameter of 0.41 mm (22 gauge) and the outer needle had an inner diameter of 1.01 mm (17 gauge). A core-sheath structure was formed in the tube. The electrospinning method was used, and the spinning machine was adjusted to a positive pressure of 14.5 kV and a negative pressure of -9.5 kV. The core layer solution syringe push glue speed is 0.15ml / h, the sheath protective layer solution syringe push glue speed is 0.3ml / h, the roller speed is 100rpm; the scanning starting point is 200mm, the scanning stroke is 10mm, the scanning speed is 10mm / s, and the outdoor temperature and humidity are maintained at (28℃, 72%), the temperature inside the machine is (26.7℃, 54%), and then directly pressurized and ejected to form a core-sheath structure of flexible protective material with thickening fiber,

[0033] (6) A flexible protective fabric is woven with thickening fibers from a flexible protective material, and the woven fabric surface density is 120 g / m 2 , cut into 5cm×5cm square pieces for testing its performance.

[0034] Example 2: A method for preparing thickening fibers for flexible protective materials, the specific preparation steps are as follows:

[0035] (1) 2.5 g of halloysite nanotubes were washed with deionized water, filtered, and repeated several times, and then dried at 80 ° C to obtain pretreated halloysite nanotubes; the pretreated halloysite nanotubes were then added to 20 g of anhydrous ethanol, mixed evenly, and 0.6 g of tetraethyl orthosilicate and 0.05 g of heptadecafluorodecyltrimethoxysilane were added dropwise. After the addition was complete, ammonia water was used to adjust the pH to 8-9, and then the mixture was reacted at room temperature for 5 h, centrifuged, washed, and dried to obtain modified halloysite nanotubes.

[0036] (2) 0.6 parts of silane coupling agent A-1120 and 80 parts of polyvinyl alcohol were mixed and stirred uniformly, and then 50 parts of nano-silica with an average particle size of 450 nm and 3 parts of modified halloysite tubes were added, and stirring and ultrasonic vibration were alternately performed until the nano-silica particles were uniformly dispersed to obtain a composite shear thickening liquid;

[0037] (3) 100 parts of the composite shear thickening liquid and 100 parts of anhydrous ethanol were mixed and stirred evenly, allowed to stand for 12 hours to remove bubbles, and then injected into a syringe as the core layer solution;

[0038] (4) 20 g of formic acid and 2.87 g of nylon were mixed and added to a magnetic stirrer. The stirring time was 100 min and the stirring temperature was 65°C.

[0039] (5) The syringes containing the core layer solution and the sheath protective layer solution were placed in the spinning machine and pushed forward simultaneously at a propulsion speed ratio of 1:2. The solutions ejected from the two syringes entered the same tube. The coaxial nozzle consisted of two concentric stainless steel needles, wherein the inner needle had an outer diameter of 0.41 mm (22 gauge) and the outer needle had an inner diameter of 1.01 mm (17 gauge). A core-sheath structure was formed in the tube. The electrospinning method was used, and the spinning machine was adjusted to a positive pressure of 14.5 kV and a negative pressure of -9.5 kV. The core layer solution was injected at a speed of 0.15 ml / h, the sheath layer solution was injected at a speed of 0.3 ml / h, and the roller speed was 100 rpm. The scanning starting point was 200 mm, the scanning stroke was 20 mm, and the scanning speed was 13 mm / s. The outdoor temperature and humidity were maintained at 28°C, 72%, and the temperature inside the machine was maintained at 26.7°C, 54%. The film was then directly pressurized and ejected to form a thickening fiber for a flexible protective material with a core-sheath structure.

[0040] (6) A flexible protective fabric is woven with thickening fibers from a flexible protective material, and the woven fabric surface density is 120 g / m 2 , cut into 5cm×5cm square pieces for testing its performance.

[0041] Example 3: A method for preparing thickening fibers for flexible protective materials. The specific preparation steps are as follows:

[0042] (1) 5 g of halloysite nanotubes were washed with deionized water, filtered, and repeated several times, and then dried at 100 ° C to obtain pretreated halloysite nanotubes; the pretreated halloysite nanotubes were then added to 30 g of anhydrous ethanol, mixed evenly, and 1 g of tetraethyl orthosilicate and 0.1 g of heptadecafluorodecyltrimethoxysilane were added dropwise. After the addition was complete, the pH was adjusted to 8-9 with ammonia water, and then reacted at room temperature for 6 h, centrifuged, washed, and dried to obtain modified halloysite tubes;

[0043] (2) 1 part of silane coupling agent A-1120 and 100 parts of polyvinyl alcohol were mixed and stirred uniformly, and then 80 parts of nano-silica with a particle size of 500 nm and 5 parts of modified halloysite tubes were added, and stirring and ultrasonic vibration were alternately performed until the nano-silica particles were uniformly dispersed to obtain a composite shear thickening liquid;

[0044] (3) 120 parts of the composite shear thickening liquid and 120 parts of anhydrous ethanol were mixed and stirred evenly, allowed to stand for 12 hours to remove bubbles, and then injected into a syringe as the core layer solution;

[0045] (4) 20 g of formic acid and 3.53 g of nylon were mixed and added to a magnetic stirrer. The stirring time was 100 min and the stirring temperature was 65°C.

[0046] (5) The syringes containing the core layer solution and the sheath protective layer solution were placed in the spinning machine and pushed forward simultaneously at a propulsion speed ratio of 1:2. The solutions ejected from the two syringes entered the same tube. The coaxial nozzle consisted of two concentric stainless steel needles, wherein the inner needle had an outer diameter of 0.41 mm (22 gauge) and the outer needle had an inner diameter of 1.01 mm (17 gauge). A core-sheath structure was formed in the tube. The electrospinning method was used, and the spinning machine was adjusted to a positive pressure of 14.5 kV and a negative pressure of -9.5 kV. The core layer solution was injected at a speed of 0.15 ml / h, the sheath layer solution was injected at a speed of 0.3 ml / h, and the roller speed was 100 rpm. The scanning starting point was 200 mm, the scanning stroke was 30 mm, and the scanning speed was 15 mm / s. The outdoor temperature and humidity were maintained at 28°C, 72%, and the temperature inside the machine was maintained at 26.7°C, 54%. The film was then directly pressurized and ejected to form a thickening fiber for a flexible protective material with a core-sheath structure.

[0047] (6) A flexible protective fabric is woven with thickening fibers from a flexible protective material, and the woven fabric surface density is 120 g / m 2 , cut into 5cm×5cm square pieces for testing its performance.

[0048] Comparative Example 1

[0049] A method for preparing thickening fiber, the specific preparation steps are as follows:

[0050] (1) 5 g of halloysite nanotubes were washed with deionized water, filtered, and repeated several times, and then dried at 100 ° C. The halloysite nanotubes were then added to 30 g of anhydrous ethanol and mixed evenly. 1.1 g of tetraethyl orthosilicate was added dropwise. After the addition was complete, the pH was adjusted to 8-9 with ammonia water. The mixture was reacted at room temperature for 6 h, centrifuged, washed, and dried to obtain modified halloysite tubes;

[0051] (2)-(6) are the same as in Example 3.

[0052] Comparative Example 2

[0053] A method for preparing thickening fiber, the specific preparation steps are as follows:

[0054] (1) 5 g of halloysite nanotubes were washed with deionized water, filtered, and repeated several times, and then dried at 100 ° C. The halloysite nanotubes were then added to 30 g of anhydrous ethanol and mixed evenly. 0.1 g of heptadecafluorodecyltrimethoxysilane was added dropwise. After the addition was complete, the pH was adjusted to 8-9 with ammonia water. The mixture was reacted at room temperature for 6 h, centrifuged, washed, and dried to obtain modified halloysite tubes;

[0055] (2)-(6) are the same as in Example 3.

[0056] Comparative Example 3

[0057] A method for preparing thickening fiber, the specific preparation steps are as follows:

[0058] (1) washing 5 g of halloysite nanotubes with deionized water, filtering, and repeating the process multiple times, and then drying at 100° C. to obtain pretreated halloysite nanotubes;

[0059] (2) 1 part of silane coupling agent A-1120 and 100 parts of polyvinyl alcohol were mixed and stirred uniformly, and then 80 parts of nano-silica with a particle size of 500 nm and 5 parts of pretreated halloysite nanotubes were added, and stirring and ultrasonic vibration were alternately performed until the nano-silica particles were uniformly dispersed to obtain a composite shear thickening liquid;

[0060] (3)-(6) are the same as in Example 3.

[0061] Comparative Example 4

[0062] A method for preparing thickening fiber, the specific preparation steps are as follows:

[0063] (1) 1 part of silane coupling agent A-1120 and 100 parts of polyvinyl alcohol were mixed and stirred uniformly, and then 30 parts of nano-silica with a particle size of 500 nm were added, and stirring and ultrasonic vibration were alternately performed until the nano-silica particles were uniformly dispersed to obtain a shear thickening liquid;

[0064] (2) 120 parts of shear thickening liquid and 60 parts of anhydrous ethanol were placed in a magnetic stirrer and stirred for two hours. After standing for 12 hours to remove bubbles, they were injected into a syringe to serve as the core layer solution.

[0065] The subsequent steps are the same as in Example 3.

[0066] Comparative Example 5

[0067] A method for preparing thickening fiber, the specific preparation steps are as follows:

[0068] (1) 1 part of silane coupling agent A-1120 and 100 parts of polyvinyl alcohol were mixed and stirred uniformly, and then 80 parts of nano-silica with a particle size of 500 nm were added, and stirring and ultrasonic vibration were alternately performed until the nano-silica particles were uniformly dispersed to obtain a shear thickening liquid;

[0069] (2) 120 parts of shear thickening liquid and 240 parts of anhydrous ethanol were placed in a magnetic stirrer and stirred for two hours. After standing for 12 hours to remove bubbles, they were injected into a syringe to serve as the core layer solution.

[0070] The subsequent steps are the same as in Example 3.

[0071] Performance Testing

[0072] Tensile strength test: According to GB 9997-88, the flexible fiber monofilaments prepared in the examples and comparative examples were tested using a JQ03new micro tensiometer. The result of each sample was obtained by averaging the 10 samples in the group. The test results are shown in Table 1.

[0073] Elongation at break test: The flexible fiber monofilaments prepared in the examples and comparative examples were tested using a CMT8102 micro-controlled electronic universal testing machine according to GB 9997-88. The test results are shown in Table 1.

[0074] Quasi-static nail penetration test: The flexible protective fabrics prepared in the examples and comparative examples were tested in accordance with GB / T 12017-1989. The displacement speed was 25 mm / min, and the distance between the nail and the test sample was 100 mm. The test results are shown in Table 2.

[0075] Dynamic knife stab test: The flexible protective fabric was laminated to 20 layers to form a laminated fabric. The laminated fabrics of the flexible protective fabrics prepared in the examples and comparative examples were tested using an ASTM D7136 drop weight impact tester in accordance with the "GA68-2019 Test Standard for Police Stab-Resistant Clothing". The test results are shown in Table 2.

[0076] Flexibility test: The flexibility test of the flexible protective fabrics prepared in the examples and comparative examples was performed using a YG541E fully automatic laser fabric wrinkle elasticity tester. The samples were subjected to a pressure load of 10 cN for 5 min. The test results are shown in Table 2.

[0077] Table 1 Test results of properties of flexible fiber monofilaments prepared in Examples and Comparative Examples

[0078]

[0079]

[0080] Table 2 Performance test results of flexible protective fabrics prepared in Examples and Comparative Examples

[0081]

[0082] Data analysis: It can be seen from Examples 1-3 that the flexible protective fiber prepared by the present invention and the woven flexible protective fabric have excellent protective performance and high flexibility. The tensile strength of the fiber monofilament can reach 643.2 MPa, the quasi-static nail puncture maximum puncture force of the fabric can reach 185.32 N, and the dynamic knife puncture maximum puncture force of the 20-layer laminated fabric can reach 634.59 N. Most importantly, the elongation at break of the fiber monofilament can reach 215.7%, the elastic recovery angle of the fabric is also relatively large, and it has good flexibility.

[0083] From Example 3 and Comparative Examples 1-5, it can be seen that the modified halloysite tubes introduced by the present invention greatly improve the protective ability of the flexible protective fabric prepared by thickening fibers. Although the addition of the halloysite tubes reduces the flexibility, the introduction of silica and perfluoroalkyl chains on the surface of the halloysite tubes effectively eliminates the effect of the halloysite tubes on the flexibility and further improves it. In addition, the halloysite tubes and the silica and perfluoroalkyl chains on the surface further improve the protective properties of the protective fabric prepared by thickening fibers. Figure 1 It can be seen that compared with the shear thickening fluid prepared in Comparative Example 4, the shear thickening fluid in Example 3 with the modified halloysite tubes has a lower critical shear rate and a lower maximum viscosity shear rate, and a higher maximum viscosity, indicating that it is more sensitive and more protective when subjected to external forces. The shear thickening fluid with a small amount of modified halloysite tubes can achieve the required performance.

[0084] Those skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of the present invention (including the claims) is limited to these examples. Within the scope of the present invention, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of the different aspects of the present invention as described above, which are not provided in detail for the sake of simplicity.

[0085] The present invention is intended to cover all such substitutions, modifications and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for preparing thickening fibers for flexible protective materials, characterized in that: The specific preparation steps are as follows: (1) The halloysite nanotubes were washed with deionized water, filtered, and repeated several times, then dried at 60-100°C, added to anhydrous ethanol, mixed evenly, and tetraethyl orthosilicate and heptafluorodecyltrimethoxysilane were added dropwise. After the addition was complete, the pH was adjusted to 8-9 with ammonia water, and then reacted at room temperature for 4-6 hours, centrifuged, washed, and dried to obtain modified halloysite tubes; (2) Mixing the silane coupling agent and polyvinyl alcohol and stirring them evenly, then adding nano-silica and modified halloysite tubes, and alternately stirring and ultrasonically vibrating until the nano-silica particles are evenly dispersed to obtain a composite shear thickening fluid; (3) Mix the composite shear thickening liquid and anhydrous ethanol and stir them evenly. Then, place them for 10-14 hours to remove bubbles and inject them into a syringe as the core layer solution. (4) After mixing nylon and formic acid, add them to a magnetic stirrer to disperse them evenly, and then inject them into a syringe to serve as the sheath protective layer solution; (5) The syringes containing the core layer solution and the sheath protective layer solution are placed in the spinning machine and pushed forward simultaneously at a pushing speed ratio of 1:

2. The solutions ejected from the two syringes enter the same tube. The coaxial nozzle is composed of two concentric stainless steel needles, forming a core-sheath structure in the tube. Then, the solution is directly pressurized and ejected to form a thickening fiber for a flexible protective material having a core-sheath structure. In the step (1), the weight ratio of halloysite nanotubes, anhydrous ethanol, tetraethyl orthosilicate and heptafluorodecyltrimethoxysilane is 1-5:10-30:0.2-1:0.01-0.1; and the weight proportions of the raw materials in the step (2) are 20-80 parts of nano-silica, 60-100 parts of polyvinyl alcohol, 0.2-1 parts of silane coupling agent and 1-5 parts of modified halloysite tubes.

2. The method for preparing a thickening fiber for a flexible protective material according to claim 1, characterized in that: In the step (1), the radial width of the halloysite nanotubes is 50-100 nm, and the radial ratio is 10-20.

3. The method for preparing a thickening fiber for a flexible protective material according to claim 1, characterized in that: The average particle size of the nano-silicon dioxide in step (2) is 400-500 nm.

4. The method for preparing a thickening fiber for a flexible protective material according to claim 1, characterized in that: The silane coupling agent in step (2) is silane coupling agent A-1120.

5. The method for preparing a thickening fiber for a flexible protective material according to claim 1, characterized in that: The weight proportions of the raw materials in step (3) are 80-120 parts of the composite shear thickening liquid and 80-120 parts of anhydrous ethanol.

6. The method for preparing a thickening fiber for a flexible protective material according to claim 1, characterized in that: In the step (4), the mass fraction of nylon in the sheath protective layer solution is 10%-15%, the mixing magnetic stirring time is 100 minutes, and the stirring temperature is 65°C.

7. The method for preparing a thickening fiber for a flexible protective material according to claim 1, characterized in that: The parameters of the spinning machine in step (5) are as follows: positive pressure 14.5 kV, negative pressure -9.5 kV; pushing speed 0.25-0.3 ml / h, roller speed 100 rpm; scanning starting point 200 mm, scanning stroke 10-30 mm, scanning speed 10-15 mm / s, outdoor temperature 28 ° C, humidity 72%, internal temperature of the machine 26.7 ° C, humidity 54%.

8. The method for preparing thickening fibers for flexible protective materials according to claim 1, characterized in that: In step (5), the two concentric stainless steel needles have an inner needle with an outer diameter of 0.41 mm and an outer needle with an inner diameter of 1.01 mm.

Images