A method for preparing a cut-resistant / flame-resistant / stealth multi-layer fabric based on waste textiles

Abstract

The application discloses a preparation method of a cut-resistant / retardant / stealth multi-layer fabric based on waste textiles, which comprises the following steps: obtaining a regenerated cellulose solution by treating waste textiles, blending the regenerated cellulose solution with a retardant and a shielding material, immersing super high molecular weight needle felt into the blended solution to prepare a cellulose aerogel base fabric, and sewing the cellulose aerogel base fabric with a camouflage fabric plated with low-density metal Al. The waste textiles are subjected to functionalization treatment, the cellulose in the waste textiles becomes a carrier of multiple functional fillers, the multi-layer structure of the fabric is ensured to have the functions of cut resistance, retardation and stealth, the super high molecular weight needle felt, the aerogel layer and the camouflage fabric layer produce a synergistic effect, the cut resistance, the retardation and the stealth of the fabric are enhanced, and the defect of insufficient functionalization degree of the fabric in the recycling process of the waste textiles in the prior art is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of recycling of waste textiles, and particularly relates to a preparation method of a cut-resistant / flame-retardant / stealth multi-layer fabric based on waste textiles. BACKGROUND

[0002] The high yield and improper disposal of waste textiles have caused serious energy waste and environmental problems. Cellulose is the most abundant organic polymer on earth, is the most widely distributed and largest amount of polysaccharide in nature, and is the main component of plant cell walls. Biomass-derived cellulose aerogels have superior physical and chemical properties such as low thermal conductivity, high specific surface area, high porosity, low cost and biocompatibility, and have wide application prospects in the fields of adsorption, oil-water separation, thermal insulation, biomedical engineering and the like.

[0003] With the development of modern war towards informatization, intelligentization and unmannedization, the requirements for individual equipment are becoming higher and higher, and military textiles will inevitably develop towards light weight, comfort and multifunction. In actual war, military equipment is prone to malfunction due to electromagnetic interference, and the temperature change generated by the operation of the equipment is also prone to be detected by infrared detectors, causing the target to be exposed. While avoiding detection by infrared technology, we also need to consider visual stealth to reduce the battle damage rate of weapons.

[0004] The prior art CN 117210958 A discloses a process for preparing regenerated fibers from waste textiles. The waste textiles are classified, cleaned and crushed. The crushed textile powder is soaked in a Na2S2O4-H2O2 solution, and during the reaction process, bleaching is performed by repeatedly pulling and lifting. The bleached textile powder is aged, yellowed and dissolved. Spinning glue is mixed with ordinary spinning glue, and then spinning is performed to obtain regenerated cellulose fibers. However, during the functionalization process in the recycling process, there are defects such as single functionalization or insufficient functionalization, which makes the combination of the recycling process and the functionalization process unsatisfactory, and it is difficult to adapt to various conditions in war.

[0005] Therefore, it is necessary to improve the preparation method of the waste textile recycling fabric in the prior art to solve the above problems. SUMMARY

[0006] The present application overcomes the shortcomings of the prior art and provides a preparation method of a cut-resistant / flame-retardant / stealth multi-layer fabric based on waste textiles, which aims to solve the problem of insufficient functionalization of the fabric in the recycling process of waste textiles in the prior art.

[0007] To achieve the above purpose, the technical scheme adopted by the present application is as follows: a preparation method of a cut-resistant / flame-retardant / stealth multi-layer fabric based on waste textiles, comprising the following steps:

[0008] S1: the waste and old textiles are treated by opening treatment, then treated by dilute inorganic acid, washed by deionized water until neutral, and dried to obtain waste and old fibers;

[0009] S2: the waste and old fibers in S1 are dissolved by ion solution to obtain regenerated cellulose solution, the flame retardant and the shielding material are dispersed in dimethyl sulfoxide to obtain dispersion liquid, the dispersion liquid and the regenerated cellulose solution are ultrasonically mixed, and then stirred to obtain regenerated cellulose mixed solution;

[0010] S3: the ultrahigh molecular weight polyethylene fiber is treated to obtain ultrahigh molecular weight needle felt, and the ultrahigh molecular weight needle felt is soaked in the regenerated cellulose mixed solution in S2;

[0011] S4: the ultrahigh molecular weight needle felt in S3 is placed in deionized water for coagulation replacement to obtain cellulose hydrogel base fabric, and the cellulose hydrogel base fabric is freeze-dried to obtain cellulose aerogel base fabric;

[0012] S5: the camouflage fabric plated with low-density metal Al on the reverse side is sewn on the surface of the cellulose aerogel base fabric in S4 to obtain a cut-resistant / retardant / stealth multi-layer fabric based on waste and old textiles.

[0013] In a preferred embodiment of the present application, the main component of the waste and old textiles in S1 is cellulose.

[0014] In a preferred embodiment of the present application, the dilute inorganic acid in S1 can be one or more of sulfuric acid, nitric acid and hydrochloric acid.

[0015] In a preferred embodiment of the present application, the dilute inorganic acid in S1 is treated in an inorganic acid with a concentration of 0.5wt% for 2h in a water bath environment at 75℃.

[0016] In a preferred embodiment of the present application, the ion solution in S2 can be 1-butyl-3-methylimidazolium chloride, and the dissolution is carried out in a water bath environment at 90℃ for 2-6h to obtain a regenerated cellulose solution with a concentration of 3-7wt%.

[0017] In a preferred embodiment of the present application, the flame retardant in S2 can be one or more of polyamide and silicon dioxide, and the shielding material can be graphene, and the concentrations of the flame retardant and the shielding material in the dispersion liquid are 5-15wt% and 3-10wt% respectively. In the process of dispersing the flame retardant and the shielding material, the ultrasonic and stirring are alternately used, and the stirring is carried out for 10-40min after ultrasonic for 10-40min, and the total ultrasonic time is 1-3h.

[0018] In a preferred embodiment of the present application, the mass ratio of the dispersion liquid and the regenerated cellulose solution in S2 is 2-3:1.

[0019] In a preferred embodiment of the present application, the ultrasonic mixing mode in S2 is ultrasonic oscillation at an ultrasonic power of 30-8000 W and a frequency of 20-120 kHz for 0.2-2 h, and the stirring mode is magnetic stirring at a speed of 0-1000 r / min at room temperature for 1-2 h.

[0020] In a preferred embodiment of the present application, the processing mode of the ultra-high molecular weight polyethylene fiber in S3 is shortening, opening and needling in sequence, the shortening length of the ultra-high molecular weight polyethylene fiber is 3-4 cm, and the fiber volume density of the ultra-high molecular weight polyethylene needle felt is 5%-20%.

[0021] In a preferred embodiment of the present application, the cellulose aerogel-based fabric in S4 is obtained by laminating and replacing the regenerated cellulose mixed solution in S3 multiple times.

[0022] The present application solves the defects in the background art and has the following beneficial effects:

[0023] The present application provides a preparation method of a cut-resistant / flammability-resistant / stealth multi-layer fabric based on waste textiles, which obtains a regenerated cellulose solution by treating waste textiles, and blends the regenerated cellulose solution with a flame retardant and a shielding material, immerses an ultra-high molecular weight needle felt to prepare a cellulose aerogel-based fabric, and sews the cellulose aerogel-based fabric with a camouflage fabric plated with low-density metal Al, so that the waste textiles are functionally treated to make the cellulose in the waste textiles become a carrier of multiple functional fillers, and ensure that the fabric has cut-resistant / flammability-resistant / stealth functions in a multi-layer structure, so that the ultra-high molecular weight needle felt, the aerogel layer and the camouflage fabric layer produce a synergistic effect, enhancing the cut-resistant / flammability-resistant / stealth properties of the fabric, and solving the defect of insufficient functionalization of the fabric in the waste textile recycling process in the prior art.

[0024] In the present application, the regenerated cellulose solution, the flame retardant and the shielding material are blended, and an aerogel layer is formed on the ultra-high molecular weight needle felt, so that the ultra-high molecular weight needle felt has cut-resistant, flammability-resistant and stealth properties at the same time, a firm structure is formed between the ultra-high molecular weight needle felt and the aerogel layer, compared with the prior art, the micro-porous structure on the aerogel can enhance the connection between the ultra-high molecular weight needle felt and the aerogel layer, improve the firmness, and at the same time, the specific surface area of the aerogel can make the aerogel have good heat insulation performance, and can improve the flammability of the fabric.

[0025] The cellulose hydrogel base fabric in the application is stacked and replaced for many times, the stacked structures of the aerogel layers have different porosities and specific surface areas, a gradient structure is formed, compared with the prior art, the porosity of the aerogel layer can gradually change from the outer layer to the inner layer, the infrared absorption and scattering capacity is increased while the strength of the aerogel structure is improved, the stealth ability of the aerogel layer is improved, the structure of the aerogel itself has good low thermal conductivity, so that the fabric has good infrared stealth performance and flame retardant performance. BRIEF DESCRIPTION OF DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application, and those skilled in the art can obtain other drawings according to these drawings without creative labor.

[0027] Figure 1 is a preparation flowchart of the preferred embodiment of the present application. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0029] In the following description, many specific details are set forth in order to provide a thorough understanding of the present application, but the present application can also be implemented in other ways different from those described herein, therefore, the scope of protection of the present application is not limited by the specific embodiments disclosed below.

[0030] As shown in Figure 1 A preparation method of a cut-resistant / flame-retardant / stealth multi-layer fabric based on waste textiles, comprising the following steps:

[0031] S1: After opening treatment of waste textiles, treat with dilute inorganic acid, and wash with deionized water to neutral, then dry to obtain waste fibers.

[0032] S2: Dissolve the waste fibers in S1 using an ionic solution to obtain a regenerated cellulose solution, disperse the flame retardant and shielding material in dimethyl sulfoxide respectively to obtain a dispersion, and ultrasonically mix the dispersion and the regenerated cellulose solution to obtain a regenerated cellulose mixed solution after stirring.

[0033] S3: The super high molecular weight polyethylene fiber is treated to obtain a super high molecular weight needle felt, and the super high molecular weight needle felt is soaked in the regenerated cellulose mixed solution in S2.

[0034] S4: The super high molecular weight needle felt in S3 is placed in deionized water for coagulation replacement to obtain a cellulose hydrogel base fabric, and the cellulose hydrogel base fabric is freeze-dried to obtain a cellulose aerogel base fabric.

[0035] S5: The camouflage fabric plated with low-density metal Al on the reverse side is sewn onto the surface of the cellulose aerogel base fabric in S4 to obtain a waste textile-based anti-cutting / flame-retardant / stealth multi-layer fabric.

[0036] The aerogel fabric has excellent thermal insulation performance due to its porous structure. When combined with a low-density aluminum fabric, the high thermal conductivity of aluminum can help quickly disperse and transfer heat, while the aerogel can retain heat, providing a more stable thermal environment, thereby improving the high-temperature resistance and flame-retardant ability of the fabric.

[0037] The low-density aluminum fabric has good electrical conductivity, so it can be used for electromagnetic shielding. By combining it with the aerogel fabric, the electromagnetic shielding function can be added while maintaining other properties of the fabric, making it suitable for applications that require electromagnetic protection, and the camouflage fabric can improve the color and electromagnetic stealth capabilities of the fabric.

[0038] The aerogel fabric itself is relatively soft, but the addition of low-density aluminum fabric can increase its structural strength, making it more durable and resistant to tearing while maintaining its lightweight nature, thereby improving the fabric's anti-cutting ability.

[0039] The density of metal Al is between 2.0 g / cm³ and 2.4 g / cm³. The combination of metal Al and aerogel on the aerogel fabric provides more active sites and adsorption centers, thereby increasing its specific surface area and improving the fabric's electromagnetic shielding ability and flame retardancy.

[0040] By treating waste textiles to obtain a regenerated cellulose solution and blending it with flame retardants and shielding materials, and then immersing the super high molecular weight needle felt to produce a cellulose aerogel base fabric, and sewing it with a camouflage fabric plated with low-density metal Al, the functionalization of the fabric is achieved through the use of waste textiles. The cellulose in the waste textiles becomes a carrier for multiple functional fillers, and the multi-layer structure of the fabric ensures that it has anti-cutting / flame-retardant / stealth functions. The super high molecular weight needle felt, aerogel layer, and camouflage fabric layer work together to enhance the fabric's anti-cutting / flame-retardant / stealth properties, solving the problem of insufficient functionalization of waste textiles in the recycling process.

[0041] The main component of the waste and old textiles in S1 is cellulose, including pure cotton textiles, pure hemp textiles, and viscose textiles, etc. The dilute inorganic acid can be one or more of sulfuric acid, nitric acid, and hydrochloric acid. The treatment method of dilute inorganic acid in S1 is to treat in 0.5wt% inorganic acid at 75℃ water bath environment for 2h. The dilute inorganic acid can acidify the cellulose in the waste and old textiles, reduce the degree of polymerization of the cellulose in the waste and old textiles, and remove the impurities between the fibers, which is a pretreatment for the fiber dissolution in S2.

[0042] The ionic solution in S2 can be 1-butyl-3-methylimidazolium chloride, and the dissolution method is to dissolve in a water bath environment at 90℃ for 2-6h to obtain a regenerated cellulose solution with a concentration of 3-7wt%. 1-butyl-3-methylimidazolium chloride is an ionic liquid with specific chemical structure and physical properties, which can effectively dissolve cellulose.

[0043] The flame retardant in S2 can be one or more of polyamide and silicon dioxide, and the shielding material can be graphene. The concentration of the flame retardant and the shielding material in the dispersion liquid is 5-15wt% and 3-10wt% respectively. When dispersing the flame retardant and the shielding material, the ultrasonic and stirring are alternately used, and after 10-40min of ultrasonic, 10-40min of stirring is used, and the total ultrasonic time is 1-3h. The cavitation effect produced by ultrasonic can produce strong hydrodynamic shear force, which helps to break the solid particles and makes them more easily dissolved. While stirring can promote convection in the solution and help the dissolved substances to be evenly distributed. The alternation of the two can more effectively accelerate the dissolution process.

[0044] The mass ratio of the dispersion liquid and the regenerated cellulose solution in S2 is 2-3:1. When the mass ratio of the dispersion liquid and the regenerated cellulose solution is 2-3:1, it can ensure that the content of the flame retardant and the shielding material and the cellulose in the mixed liquid reaches a balance, and at the same time, it ensures the formation of the aerogel layer in S4 and the possession of multiple functions.

[0045] The ultrasonic mixing method in S2 is to ultrasonically oscillate for 0.2-2h at an ultrasonic power of 30-8000W and a frequency of 20-120kHz, and the stirring method is to stir at a speed of 0-1000r / min at room temperature for 1-2h by a magnetic stirrer, which can make the mixture of the dispersion liquid and the regenerated cellulose solution uniform.

[0046] The treatment method of the ultrahigh molecular weight polyethylene fiber in S3 is shortening, opening, and needling in sequence. The shortening length of the ultrahigh molecular weight polyethylene fiber is 3-4cm, and the fiber volume density of the ultrahigh molecular weight polyethylene needle felt is 5%-20%.

[0047] The regenerated cellulose solution, the flame retardant and the shielding material are blended, and an aerogel layer is formed on the ultra-high molecular weight needle felt, so that the ultra-high molecular weight needle felt has the properties of cut resistance, flame resistance and stealth at the same time, a firm structure is formed between the ultra-high molecular weight needle felt and the aerogel layer, the micro-porous structure on the aerogel can enhance the connection between the ultra-high molecular weight needle felt and the aerogel layer, improve the firmness, and at the same time, the specific surface area of the aerogel can make the aerogel have good heat insulation performance, and the flame resistance of the fabric can be improved.

[0048] The cellulose hydrogel-based fabric in S4 is subjected to multiple layering and replacement by the regenerated cellulose mixed solution in S3, to obtain a cellulose aerogel-based fabric. In each layering, the fabric soaked in the mixed solution is freeze-dried to form an aerogel structure, and then soaked in the mixed solution again. The aerogel formed in each layering is fully solidified, reducing the possibility of defects.

[0049] In the multiple layering and replacement of S4, with the increase of the replacement times, the concentration of the flame retardant and the shielding material in the dispersion liquid increases, and the freeze-drying speed increases. When the concentration of the flame retardant and the shielding material in the dispersion liquid decreases, the freeze-drying speed decreases, which can increase the porosity of the outer layer,

[0050] The cellulose hydrogel-based fabric is subjected to multiple layering and replacement, and with the increase of the replacement times, the concentration of the flame retardant and the shielding material in the dispersion liquid is increased and the freeze-drying speed is accelerated, the layering structure of the aerogel layer has different porosities and specific surface areas, forming a gradient structure, which can make the porosity of the aerogel layer gradually decrease from the outer layer to the inner layer, the high porosity of the outer layer makes the aerogel layer have good electromagnetic shielding ability, the low porosity of the inner layer maintains the stability and mechanical strength of the structure, improves the stealth ability of the aerogel layer, and the structure of the aerogel itself has good low thermal conductivity, so that the fabric has good infrared stealth performance and flame resistance.

[0051] The deionized water is more than 10 times the mass of the hydrogel. The deionized water washes the residual solution attached to the fabric and cools the hydrogel, which helps the hydrogel form an aerogel structure. The deionized water is more than 10 times the mass of the hydrogel to ensure the degree of washing and cooling. The freezing time is 4-12 h (preferably 6-8 h), the freezing temperature is -80℃ to -20℃, the drying time is 12-20 h (preferably 15-18 h), and the drying temperature is -50℃ to 30℃. Suitable freezing and drying conditions can ensure the functionality and stability of the aerogel structure. Example 1

[0052] S1 recovers waste pure cotton textiles, and opens the waste cotton fabric to obtain waste cotton fibers by using a precision shuttle multifunctional opening machine;

[0053] S2 5 g of waste cotton fibers were taken and added to 500 ml of dilute sulfuric acid with a concentration of 0.5 wt%, heated to 75°C in a water bath for 2 h, then washed to neutral with deionized water, then dried in an oven at 60°C for standby;

[0054] S3 The fibers obtained in step S2 were immediately put into a Raymond mill after being frozen in liquid nitrogen and ground into powder;

[0055] S4 2 g of 1-butyl-3-methylimidazolium chloride was weighed into a sealed bottle and placed in a 90°C oil bath until transparent; 0.12 g of the powder obtained in step S3 was placed in a sealed bottle and heated in an oil bath at 90°C until the fibers were completely dissolved to obtain a regenerated cellulose solution;

[0056] S5 0.5 g of flame retardant was dispersed in 5 g of dimethyl sulfoxide to obtain a dispersion; during dispersion, after each 0.5 h of ultrasonic, 0.5 h of stirring was performed;

[0057] S6 The regenerated cellulose solution obtained in step S4 was mixed with the dispersion obtained in step S5, then ultrasonic was performed at a power of 180 W and a frequency of 40 kHz for 1 h, and then a magnetic stirrer was used to stir at a speed of 300 r / min at room temperature for 1 h to obtain a flame-retardant regenerated cellulose solution;

[0058] S7 The cellulose hydrogel obtained in step S6 was placed in deionized water for coagulation and sufficient replacement to remove excess ionic liquid;

[0059] S8 The cellulose hydrogel obtained in step S7 was frozen for 6 h and then dried for 18 h to obtain a cellulose aerogel with a porous structure;

[0060] From Figure 1 It can be seen that the prepared cellulose aerogel has a good pore structure, and the flame retardant particles are uniformly dispersed therein, and the two are well combined.

[0061] Comparative Example 1

[0062] The difference between Comparative Example 1 and Example 1 is that no flame retardant is added to the regenerated cellulose spinning solution, specifically:

[0063] S1 Waste pure cotton textiles were recovered, and a precision shuttle multifunctional opening machine was used to open the waste cotton cloth to obtain waste cotton fibers;

[0064] S2 5 g of waste cotton fibers were taken and added to 500 ml of dilute sulfuric acid with a concentration of 0.5 wt%, heated to 75°C in a water bath for 2 h, then washed to neutral with deionized water, then dried in an oven at 60°C for standby;

[0065] S3 The fibers obtained in step S2 were immediately put into a Raymond mill after being frozen in liquid nitrogen and ground into powder;

[0066] S4 Take 2 g 1-butyl-3-methylimidazolium chloride in a sealed bottle, put it into a 90°C oil bath pot until transparent; take 0.12 g of the powder obtained in step S3 and put it into a sealed bottle, heat it in a 90°C oil bath pot until the fibers are completely dissolved, to obtain a regenerated cellulose solution;

[0067] S5 Disperse 0.5 g of the flame retardant in 5 g of dimethyl sulfoxide; during dispersion, stir for 0.5 h after each 0.5 h of ultrasonic treatment;

[0068] S6 Place the cellulose hydrogel obtained in step S5 in deionized water to coagulate and replace the excess ionic liquid;

[0069] S7 Freeze the cellulose hydrogel obtained in step S6 for 6 h and then dry it for 18 h to obtain a cellulose aerogel with a porous structure;

[0070] The flame retardant performance of the multifunctional cellulose-based aerogel is analyzed by vertical combustion method, limiting oxygen index test, etc.

[0071] Table 1 Comparison of limiting oxygen index and specific surface area of Example 1 and Comparative Example 1

[0072] Example Limiting oxygen index Specific surface area g / cm 3 ]] Example 1 45.7% 278 Comparative Example 1 19.5% 313

[0073] As can be seen from Table 1, compared with Comparative Example 1, Example 1 still has a large specific surface area after adding flame-retardant particles, and at the same time, good flame-retardant performance is also imparted. Example 2

[0074] S1 Recover waste pure cotton textiles and use a precision multifunctional opening machine to open the waste cotton cloth to obtain waste cotton fibers;

[0075] S2 Take 5 g of waste cotton fibers and add them to 500 ml of dilute sulfuric acid with a concentration of 0.5 wt%; heat the mixture in a water bath to 75°C for 2 h, then wash it with deionized water until it is neutral, and then dry it in an oven at 60°C for standby;

[0076] S3 Freeze the fibers obtained in step S2 in liquid nitrogen and immediately put them into a Raymond mill to grind them into powder;

[0077] S4 Take 2 g of 1-butyl-3-methylimidazolium chloride in a sealed bottle, put it into a 90°C oil bath pot until transparent; take 0.12 g of the powder obtained in step S3 and put it into a sealed bottle, heat it in a 90°C oil bath pot until the fibers are completely dissolved, to obtain a regenerated cellulose solution;

[0078] S5 Disperse 0.5 g of the flame retardant in 5 g of dimethyl sulfoxide to obtain a dispersion; during dispersion, stir for 0.5 h after each 0.5 h of ultrasonic treatment;

[0079] S6mixing the regenerated cellulose solution obtained in step S4 with the dispersion obtained in step S5, then ultrasonic treatment under ultrasonic power of 180 W and frequency of 40 kHz for 1 h, and then stirring at room temperature at a speed of 300 r / min for 1 h using a magnetic stirrer to obtain a flame-retardant regenerated cellulose solution;

[0080] S7shortening the ultrahigh molecular weight polyethylene fiber to 3-4 cm, and obtaining an ultrahigh molecular weight needled felt with a volume content of 7% through the steps of opening and needling;

[0081] S8immersing the mixed solution obtained in step S6 in the ultrahigh molecular weight polyethylene needled felt obtained in step S7;

[0082] S9placing the cellulose hydrogel-based fabric obtained in step S8 in deionized water for coagulation and sufficient replacement to remove excess ionic liquid;

[0083] S10freezing the cellulose hydrogel-based fabric obtained in step S9 for 6 h and then drying for 18 h to obtain a cellulose aerogel-based fabric with a porous structure;

[0084] S11sewing the camouflage fabric plated with low-density metal Al on the reverse side onto the surface of the cellulose aerogel-based fabric obtained in step S10 to obtain a cut-resistant / flame-retardant / stealth multi-layer fabric based on waste textiles.

[0085] Comparative Example 2

[0086] The difference between Comparative Example 2 and Example 2 is that no ultrahigh molecular weight polyethylene cut-resistant layer is added to the cellulose aerogel, specifically:

[0087] S1recovering waste pure cotton textiles, and opening the waste cotton textiles using a precision shuttle multifunctional opener to obtain waste cotton fibers;

[0088] S2adding 5 g of waste cotton fibers to 500 ml of dilute sulfuric acid with a concentration of 0.5 wt%, heating to 75℃ in a water bath for 2 h, then washing to neutral with deionized water, and then drying in an oven at 60℃ for standby;

[0089] S3freezing the fibers obtained in step S2 in liquid nitrogen and immediately feeding them into a Raymond mill to grind into powder;

[0090] S4weighing 2 g of 1-butyl-3-methylimidazolium chloride into a sealed bottle, placing it in a 90℃ oil bath until it becomes transparent, and weighing 0.12 g of the powder obtained in step S3 into a sealed bottle, and placing it in an oil bath at 90℃ until the fibers are completely dissolved to obtain a regenerated cellulose solution;

[0091] S5 5 g dimethyl sulfoxide was mixed with the regenerated cellulose solution obtained in step S4, and then ultrasonic was performed under the power of 180 W and the frequency of 40 kHz for 1 h, and then a magnetic stirrer was used to stir at the speed of 300 r / min at room temperature for 1 h;

[0092] S6 The cellulose hydrogel obtained in step S5 was placed in deionized water for coagulation and sufficient replacement to remove excess ionic liquid;

[0093] S7 The cellulose hydrogel obtained in step S6 was frozen for 6 h and then dried for 18 h to obtain a cellulose aerogel with a porous structure;

[0094] S8 The camouflage fabric plated with low-density metal Al on the reverse side was sewn onto the surface of the cellulose aerogel base fabric obtained in step S7.

[0095] The cutting resistance grade of the multifunctional cellulose-based aerogel was analyzed by using a QC-200A cut-resistant glove tester.

[0096] Table 2 Comparison of cutting circle number and thickness of Example 2 and Comparative Example 2

[0097] Example Cutting cycles Thickness (mm) Example 2 40.98 2 Comparative Example 2 7.16 2

[0098] As can be seen from Table 2, compared with Comparative Example 2, under the condition of the same thickness, after adding the super high molecular weight polyethylene needle felt cut-resistant layer, the cut-resistant performance of Example 2 is significantly improved. Example 3

[0099] S1 Waste pure cotton textiles were recovered, and waste cotton fibers were obtained by opening the waste cotton textiles using a precision shuttle multifunctional opener;

[0100] S2 5 g of waste cotton fibers were added to 500 ml of dilute sulfuric acid with a concentration of 0.5 wt%, heated to 75℃ in a water bath for 2 h, then washed to neutral with deionized water, and then dried in an oven at 60℃ for standby;

[0101] S3 The fibers obtained in step S2 were immediately put into a Raymond mill after being frozen in liquid nitrogen, and were ground into powder;

[0102] S4 2 g of 1-butyl-3-methylimidazolium chloride was weighed in a sealed bottle and placed in a 90℃ oil bath until transparent; 0.12 g of the powder obtained in step S3 was placed in a sealed bottle and heated in an oil bath at 90℃ until the fibers were completely dissolved to obtain a regenerated cellulose solution;

[0103] S5 0.5 g of a flame retardant and 0.25 g of a shielding material were dispersed in 5 g of dimethyl sulfoxide to obtain a dispersion liquid; during dispersion, stirring was performed for 0.5 h after each ultrasonic for 0.5 h;

[0104] S6mix the regenerated cellulose solution obtained in step S4 with the dispersion liquid obtained in step S5 at a ratio of 1:2, then ultrasonic for 1 h under ultrasonic wave with power of 180 W and frequency of 40 kHz, and then stir at room temperature for 1 h using a magnetic stirrer at a speed of 300 r / min to obtain a regenerated cellulose dispersion liquid;

[0105] S7cut the ultrahigh molecular weight polyethylene fiber into 3-4 cm, and obtain an ultrahigh molecular weight needled felt with a volume content of 7% by opening, needling and other steps;

[0106] S8fully immerse the regenerated cellulose dispersion liquid obtained in step S6 in the ultrahigh molecular weight polyethylene needled felt obtained in step S7;

[0107] S9place the cellulose hydrogel base fabric obtained in step S8 in deionized water to coagulate and fully displace, and remove the excess ionic liquid;

[0108] S10freeze the cellulose hydrogel base fabric obtained in step S9 at-60℃ for 6 h, and then dry for 18 h to obtain a cellulose aerogel base fabric with a porous structure;

[0109] S11stack the cellulose aerogel base fabric obtained in step S10 in the regenerated cellulose dispersion liquid in step S11 twice, and perform a freeze-drying process after each time of immersion in the regenerated cellulose dispersion liquid to obtain a stacked cellulose aerogel base fabric;

[0110] S12sew the camouflage fabric plated with low-density metal Al on the reverse side onto the surface of the stacked cellulose aerogel base fabric obtained in step S11 to obtain a cut-resistant / flame-retardant / stealth multi-layer fabric based on waste textiles. Example 4

[0111] S1recover waste pure cotton textiles, and open the waste cotton textiles using a precision multi-functional opener to obtain waste cotton fibers;

[0112] S2add 5 g of waste cotton fibers into 500 ml of dilute sulfuric acid with a concentration of 0.5 wt%, heat to 75℃ in a water bath for 2 h, then wash to neutral with deionized water, and then dry in an oven at 60℃ for standby;

[0113] S3after freezing the fibers obtained in step S2 in liquid nitrogen, immediately put them into a Raymond mill to grind into powder;

[0114] S4weigh 2 g of 1-butyl-3-methylimidazolium chloride into a sealed bottle, and place it in a 90℃ oil bath until it becomes transparent; weigh 0.12 g of the powder obtained in step S3 into a sealed bottle, and place it in an oil bath at 90℃ until the fibers are completely dissolved to obtain a regenerated cellulose solution;

[0115] S5 dispersing 0.4 g flame retardant and 0.2 g shielding material in 5 g dimethyl sulfoxide to obtain a dispersion liquid; during the dispersion, stirring for 0.5 h after ultrasonic treatment for 0.5 h;

[0116] S6 mixing the regenerated cellulose solution obtained in step S4 with the dispersion liquid obtained in step S5 at a ratio of 1:2, then ultrasonic treatment for 1 h under ultrasonic wave with a power of 180 W and a frequency of 40 kHz, and then stirring at room temperature at a speed of 300 r / min for 1 h using a magnetic stirrer to obtain a regenerated cellulose dispersion liquid;

[0117] S7 shortening the ultrahigh molecular weight polyethylene fiber to 3-4 cm, and obtaining an ultrahigh molecular weight needled felt with a volume content of 7% through the steps of opening and needling;

[0118] S8 fully impregnating the regenerated cellulose dispersion liquid obtained in step S6 in the ultrahigh molecular weight polyethylene needled felt obtained in step S7;

[0119] S9 placing the cellulose hydrogel-based fabric obtained in step S8 in deionized water for coagulation and sufficient replacement to remove excess ionic liquid;

[0120] S10 freezing the cellulose hydrogel-based fabric obtained in step S9 at-60℃ for 6 h and then drying for 18 h to obtain a cellulose aerogel-based fabric with a porous structure;

[0121] S11 continuing to prepare two groups of dispersion liquids, each group of dispersion liquid using 5 g of dimethyl sulfoxide, and the flame retardant and shielding material in each group being 0.5 g and 0.25 g, and 0.6 g and 0.3 g respectively, and mixing the two groups of dispersion liquids with the regenerated cellulose solution in step S4 at a ratio of 1:2 to obtain a regenerated cellulose dispersion liquid;

[0122] S12 stacking the cellulose aerogel-based fabrics obtained in step S10 in the two groups of regenerated cellulose dispersion liquids in step S11 in order of increasing concentration, and performing a freeze-drying process after each time of immersion in the regenerated cellulose dispersion liquid to obtain a stacked cellulose aerogel-based fabric;

[0123] S13 sewing a camouflage fabric plated with low-density metal Al on the reverse side to the surface of the stacked cellulose aerogel-based fabric obtained in step S12 to obtain a cut-resistant / flame-retardant / stealth multi-layer fabric based on waste textiles. Example 5

[0124] S1 recycling waste pure cotton textiles, and opening the waste cotton textiles using a precision multi-functional opening machine to obtain waste cotton fibers;

[0125] S2 5 g of waste cotton fiber was added to 500 ml of 0.5 wt% dilute sulfuric acid, heated to 75°C in a water bath for 2 h, then washed with deionized water until neutral, then dried in an oven at 60°C for standby;

[0126] S3 The fiber obtained in step S2 was immediately put into a Raymond mill after being frozen in liquid nitrogen, and was ground into powder;

[0127] S4 2 g of 1-butyl-3-methylimidazolium chloride was weighed in a sealed bottle and placed in a 90°C oil bath until transparent; 0.12 g of the powder obtained in step S3 was placed in a sealed bottle and placed in a 90°C oil bath until the fiber was completely dissolved, obtaining a regenerated cellulose solution;

[0128] S5 0.3 g of flame retardant and 0.15 g of shielding material were dispersed in 5 g of dimethyl sulfoxide to obtain a dispersion; during dispersion, after each 0.5 h of ultrasonic, 0.5 h of stirring was performed;

[0129] S6 The regenerated cellulose solution obtained in step S4 was mixed with the dispersion obtained in step S5 at a ratio of 1:2, then ultrasonic was performed at a power of 180 W and a frequency of 40 kHz for 1 h, and then a magnetic stirrer was used to stir at a speed of 300 r / min at room temperature for 1 h, obtaining a regenerated cellulose dispersion;

[0130] S7 The ultrahigh molecular weight polyethylene fiber was cut into 3-4 cm, and through the steps of opening and needling, an ultrahigh molecular weight needled felt with a volume content of 7% was obtained;

[0131] S8 The regenerated cellulose dispersion obtained in step S6 was fully impregnated in the ultrahigh molecular weight polyethylene needled felt obtained in step S7;

[0132] S9 The cellulose hydrogel base fabric obtained in step S8 was placed in deionized water for coagulation and sufficient displacement to remove excess ionic liquid;

[0133] S10 The cellulose hydrogel base fabric obtained in step S9 was frozen at -60°C for 6 h and then dried for 18 h, obtaining a cellulose aerogel base fabric with a porous structure;

[0134] S11 Continue to configure multiple dispersions, each of which uses 5 g of dimethyl sulfoxide, and the amount of flame retardant and shielding material in each group is 0.5 g and 0.25 g, 0.7 g and 0.35 g respectively, and the two groups of dispersions are mixed with the regenerated cellulose solution in step S4 at a ratio of 1:2, obtaining a regenerated cellulose dispersion;

[0135] S12 stack the cellulose aerogel base fabric obtained in step S10 in the two groups of regenerated cellulose dispersion solutions in S11 in order of concentration from small to large, and after each immersion in the regenerated cellulose dispersion solution, a freeze-drying process is carried out once, to obtain a stacked cellulose aerogel base fabric;

[0136] S13 sew the camouflage fabric plated with low-density metal Al on the reverse side to the surface of the stacked cellulose aerogel base fabric obtained in step S12 to obtain a waste textile-based anti-cutting / flame-retardant / stealth multi-layer fabric. Example 6

[0137] S1 recycle waste pure cotton textiles, and use a precision multi-functional opening machine to open the waste cotton fabric to obtain waste cotton fibers;

[0138] S2 take 5 g of waste cotton fibers and add them to 500 ml of dilute sulfuric acid with a concentration of 0.5 wt%, heat to 75℃ in a water bath for 2 h, then wash to neutral with deionized water, then dry in an oven at 60℃ for standby use;

[0139] S3 after the fibers obtained in step S2 are frozen in liquid nitrogen, immediately put them into a Raymond mill to grind into powder;

[0140] S4 weigh 2 g of 1-butyl-3-methylimidazolium chloride into a sealed bottle, and place it in a 90℃ oil bath until it is transparent; weigh 0.12 g of the powder obtained in step S3 into a sealed bottle, and place it in a 90℃ oil bath until the fibers are completely dissolved, to obtain a regenerated cellulose solution;

[0141] S5 disperse 0.3 g of a flame retardant and 0.15 g of a shielding material in 5 g of dimethyl sulfoxide to obtain a dispersion; during dispersion, stir for 0.5 h after each 0.5 h of ultrasonic treatment;

[0142] S6 mix the regenerated cellulose solution obtained in step S4 with the dispersion obtained in step S5 at a ratio of 1:2, then ultrasonically treat for 1 h at a power of 180 W and a frequency of 40 kHz, and then use a magnetic stirrer to stir at a speed of 300 r / min at room temperature for 1 h, to obtain a regenerated cellulose dispersion;

[0143] S7 cut the ultrahigh molecular weight polyethylene fibers into 3-4 cm, and obtain an ultrahigh molecular weight needled felt with a volume content of 7% through opening, needling, etc;

[0144] S8 fully immerse the regenerated cellulose dispersion obtained in step S6 in the ultrahigh molecular weight polyethylene needled felt obtained in step S7;

[0145] S9 place the cellulose hydrogel base fabric obtained in step S8 in deionized water to coagulate and fully displace, and remove excess ionic liquid;

[0146] S10 freeze the cellulose hydrogel base fabric obtained in step S9 at -70 °C for 6 h and then dry for 18 h to obtain a cellulose aerogel base fabric with a porous structure;

[0147] S11 continue to configure multiple dispersions, each of which uses 5 g of dimethyl sulfoxide, and each group has 0.5 g and 0.25 g, 0.7 g and 0.35 g of flame retardant and shielding material, respectively, and mix the two dispersions with the regenerated cellulose solution in step S4 at a ratio of 1:2 to obtain a regenerated cellulose dispersion;

[0148] S12 stack the cellulose aerogel base fabric obtained in step S10 in the two groups of regenerated cellulose dispersions in S11 in order of increasing concentration, and perform a freeze-drying process after each immersion in the regenerated cellulose dispersion to obtain a stacked cellulose aerogel base fabric;

[0149] S13 sew the camouflage fabric plated with low-density metal Al on the reverse side to the surface of the stacked cellulose aerogel base fabric obtained in step S12 to obtain a cut-resistant / flame-retardant / stealth multi-layer fabric based on waste textiles. Example 7

[0150] S1 recycle waste pure cotton textiles, and use a precision shuttle multifunctional opening machine to open the waste cotton fabric to obtain waste cotton fibers;

[0151] S2 take 5 g of waste cotton fibers and add them to 500 ml of 0.5 wt% concentrated sulfuric acid, heat to 75 °C in a water bath for 2 h, then wash to neutral with deionized water, then dry in an oven at 60 °C for standby;

[0152] S3 freeze the fibers obtained in step S2 in liquid nitrogen and immediately put them into a Raymond mill to grind into powder;

[0153] S4 weigh 2 g of 1-butyl-3-methylimidazolium chloride into a sealed bottle and place it in a 90 °C oil bath until it is transparent; weigh 0.12 g of the powder obtained in step S3 into a sealed bottle and place it in an oil bath at 90 °C until the fibers are completely dissolved to obtain a regenerated cellulose solution;

[0154] S5 disperse 0.3 g of flame retardant and 0.15 g of shielding material in 5 g of dimethyl sulfoxide to obtain a dispersion; during dispersion, stir for 0.5 h after each 0.5 h of ultrasonic treatment;

[0155] S6 mix the regenerated cellulose solution obtained in step S4 with the dispersion obtained in step S5 at a ratio of 1:2, then ultrasonic for 1 h at a power of 180 W and a frequency of 40 kHz, and then stir at room temperature using a magnetic stirrer at a speed of 300 r / min for 1 h to obtain a regenerated cellulose dispersion;

[0156] S7 cut the ultra-high molecular weight polyethylene fiber into 3-4 cm, and obtained an ultra-high molecular weight needled felt with a volume content of 7% through the steps of opening and needling;

[0157] S8 fully impregnated the regenerated cellulose dispersion solution obtained in step S6 into the ultra-high molecular weight polyethylene needled felt obtained in step S7;

[0158] S9 placed the cellulose hydrogel base fabric obtained in step S8 in deionized water for coagulation and sufficient replacement to remove excess ionic liquid;

[0159] S10 dried the cellulose hydrogel base fabric obtained in step S9 after freezing for 6 h at -80°C for 18 h to obtain a cellulose aerogel base fabric with a porous structure;

[0160] S11 continued to configure multiple dispersions, each using 5 g of dimethyl sulfoxide, and each group of dispersion had 0.5 g and 0.25 g, 0.7 g and 0.35 g of the flame retardant and shielding material respectively, and mixed the two groups of dispersions with the regenerated cellulose solution in step S4 at a ratio of 1:2 to obtain a regenerated cellulose dispersion;

[0161] S12 stacked the cellulose aerogel base fabric obtained in step S10 in the two groups of regenerated cellulose dispersions in S11 in order of increasing concentration, and performed a freeze-drying process after each time of immersion in the regenerated cellulose dispersion to obtain a stacked cellulose aerogel base fabric;

[0162] S13 sewed the camouflage fabric plated with low-density metal Al on the reverse side onto the surface of the stacked cellulose aerogel base fabric obtained in step S12 to obtain a cut-resistant / flame-retardant / stealth multi-layer fabric based on waste textiles.

[0163] The fabrics in examples 3-7 were cut into samples of the same size and thickness, and the samples were respectively tested for cut resistance, flame retardancy and electromagnetic shielding performance. When performing the electromagnetic shielding performance test, the sample was placed in an electromagnetic shielding test system, electromagnetic waves were emitted and the signal strength received at the receiving end was recorded. By comparing the signal strength of the transmitting end and the receiving end, the electromagnetic shielding effectiveness of the fabric was calculated.

[0164] Table 3 Cut resistance, flame retardancy and electromagnetic shielding performance test values of examples 3-7

[0165] Example Limiting oxygen index Cutting cycles Decibels (dB) Example 3 46.3% 43.57 4.0-9.4 Example 4 47.5% 44.62 4.7-10.9 Example 5 48.9% 46.17 5.6-12.1 Example 6 50.3% 46.93 5.8-12.3 Example 7 52.1% 47.38 6.1-12.7

[0166] As shown in Table 3, in Examples 3-5, as the dispersion amplitude of the regenerated cellulose dispersion solution increases, the gradient structure of the aerogel layer is more obvious, the limiting oxygen index, the cutting circle number and the decibel value of the sample all increase, and the cutting resistance, the flame retardancy and the electromagnetic shielding performance of the sample are all improved. In Examples 5-7, as the speed of freeze-drying increases, the limiting oxygen index, the cutting circle number and the decibel value of the sample all increase, and the cutting resistance, the flame retardancy and the electromagnetic shielding performance of the sample are all improved.

[0167] The above is based on the ideal embodiment of the application, through the above description, relevant personnel can make various changes and modifications without deviating from the technical idea of the application. The technical scope of the application is not limited to the content of the specification, and the technical scope must be determined according to the scope of claims.

Claims

1. A method for the preparation of a cut-resistant / flame-resistant / stealth multi-layer fabric based on waste textiles, characterized by, The method comprises the following steps: S1: treating the waste textiles by opening treatment, then treating with dilute inorganic acid, and washing with deionized water until neutral, and drying to obtain waste fibers; S2: dissolving the waste fibers in S1 with ionic solution to obtain regenerated cellulose solution, dispersing flame retardant and shielding material in dimethyl sulfoxide to obtain dispersion liquid, and mixing the dispersion liquid and the regenerated cellulose solution by ultrasonic mixing to obtain regenerated cellulose mixed solution; S3: treating ultra-high molecular weight polyethylene fibers to obtain ultra-high molecular weight needle felt, and immersing the ultra-high molecular weight needle felt in the regenerated cellulose mixed solution in S2; S4: placing the ultra-high molecular weight needle felt in S3 in deionized water for coagulation and replacement to obtain cellulose hydrogel base fabric, and freeze-drying the cellulose hydrogel base fabric to obtain cellulose aerogel base fabric; S5: sewing the camouflage fabric plated with low-density metal Al on the reverse side on the surface of the cellulose aerogel base fabric in S4 to obtain a cut-resistant / retardant / stealth multi-layer fabric based on waste textiles.

2. A method of making a cut-resistant / flame resistant / stealth multi-layer fabric based on waste textiles according to claim 1, characterized in that: The main component of the waste textiles in S1 is cellulose.

3. A method of making a cut-resistant / flame resistant / stealth multi-layer fabric based on waste textiles according to claim 1, characterized in that: The dilute inorganic acid in S1 is one or more of sulfuric acid, nitric acid and hydrochloric acid.

4. A method of making a cut-resistant / flame resistant / stealth multi-layer fabric based on waste textiles according to claim 3, characterized in that: The dilute inorganic acid treatment in S1 is 2h in inorganic acid with a concentration of 0.5wt% in a water bath environment at 75℃.

5. A method of making a cut-resistant / flame resistant / stealth multi-layer fabric based on waste textiles as claimed in claim 1, wherein: The ionic solution in S2 is 1-butyl-3-methylimidazolium chloride, and the dissolving method is 2-6h in a water bath environment at 90℃ to obtain a regenerated cellulose solution with a concentration of 3-7wt%.

6. A method of making a cut-resistant / flame resistant / stealth multi-layer fabric based on waste textiles as claimed in claim 1, wherein: The flame retardant in S2 is one or more of polyamide and silicon dioxide, and the shielding material is graphene, and the concentration of the flame retardant and the shielding material in the dispersion liquid is 5-15wt% and 3-10wt% respectively, and the ultrasonic and stirring interval alternation method is adopted when dispersing the flame retardant and the shielding material, and the stirring time is 10-40min after ultrasonic for 10-40min, and the total ultrasonic time is 1-3h.

7. A method of making a cut-resistant / flame resistant / stealth multi-layer fabric based on waste textiles as claimed in claim 1, wherein: The mass ratio of the dispersion liquid and the regenerated cellulose solution in S2 is 2-3:

1.

8. A method of making a cut-resistant / flame resistant / stealth multi-layer fabric based on waste textiles according to claim 1, characterized in that: The ultrasonic mixing method in S2 is ultrasonic oscillation at a power of 30-8000W and a frequency of 20-120kHz for 0.2-2h, and the stirring method is magnetic stirring at a speed of 0-1000r / min at room temperature for 1-2h.

9. A method of manufacturing a cut-resistant / flame-resistant / stealth multi-layer fabric based on waste and used textiles according to claim 1, characterized in that: The treatment method of the ultra-high molecular weight polyethylene fibers in S3 is shortening, opening and needling in sequence, the shortening length of the ultra-high molecular weight polyethylene fibers is 3-4cm, and the fiber volume density of the ultra-high molecular weight needle felt is 5%-20%.

10. A method of making a cut-resistant / flame resistant / stealth multi-layer fabric based on waste textiles as claimed in claim 1, wherein: The cellulose aerogel base fabric is obtained by repeatedly stacking and replacing the regenerated cellulose mixed solution in S3.

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