Preparation Method of Graphene Cloud Velvet

Abstract

The present invention discloses a preparation method of graphene cloud fluff, which relates to the technical field of cloud fluff. First, styrene amine is subjected to an addition reaction with graphite scales to introduce double bonds, and then it is mixed with γ-methacryloyloxypropyltrimethoxysilane to prepare a hydrogel, forming a double cross-linked network, and then it is prepared into an aerogel to improve the strength of the cloud fluff; titanium dioxide nanocrystals are attached to the aerogel, and then after hydrothermal reaction, dehydration occurs, and crystal form transformation strengthens the porosity and improves the photocatalytic activity, so that the concentration of reactive oxygen is increased, further improving its antibacterial performance. Secondly, the cloud fluff is formed by polyester hollow profiled spinning to form a penetrating porous structure, which can enrich more static air to enhance the heat preservation effect; during the fiber forming process, an all-round annular high-speed strong cold air blowing technology is adopted to quickly cool the spinning melt instantly with extremely small error, so that the bulk density of the cloud fluff is very small. The cloud fluff prepared by the present invention has the effects of high strength, antibacterial property and heat preservation.

Description

Technical Field

[0001] The present invention relates to the technical field of cloud velvet, and specifically to a preparation method of graphene cloud velvet. Background Art

[0002] Cloud velvet is actually a kind of fiber made by a new process. It has good warmth retention and high elasticity, is comfortable and light. Usually, cloud velvet can be processed and applied in many fields such as clothing and household items.

[0003] Cloud velvet is a new fiber completely different from the traditional one. It adopts a brand-new polyester production process and a technology of blending multiple PET polymer materials. After being processed into spherical velvet, it feels very comfortable to the touch, giving a feeling like coagulated fat. When you hold it up with both hands, it also has a sense of fullness. Now cloud velvet can be used as the filling of many items, including pillows, quilts, fabric dolls, sofas, soft beds, etc.

[0004] However, there are still many defects in the current preparation of cloud velvet. One is that the hollowness of cloud velvet is relatively low. High hollowness with thin walls is easy to break, consuming a large amount of materials, thus increasing the usage degree of raw materials. The other is that the addition of graphene is prone to agglomeration due to π-π conjugate bonds. While the fiber effect and performance are poor, the bactericidal effect of graphene is also greatly reduced. Therefore, the present invention proposes a preparation method of graphene cloud velvet to solve the above problems. Summary of the Invention

[0005] The purpose of the present invention is to provide a preparation method of graphene cloud velvet to solve the problems existing in the prior art.

[0006] To solve the above technical problems, the present invention provides the following technical solution: A preparation method of graphene cloud velvet, including the following preparation steps:

[0007] (1) First, weigh 1 part of graphite flakes and 10 parts of sodium chloride for ball milling, and the ball milling time is 0.5 - 1.5 h; then add 5 - 10 parts of p-aminostyrene, mix and ball mill for 0.5 - 1.5 h; finally, add 16 - 20 parts of nitrite and mix for ball milling for 24 h. After that, wash twice with deionized water, and then vacuum dry at 0.085 MPa and 50 °C to obtain modified graphene;

[0008] (2) Mix 1 - 5 parts of modified graphene with 50 parts of deionized water, stir at a speed of 350 rpm for 1 - 2 h, then ultrasonically treat at 30 kHz for 30 min, and continue to stir for 1 - 2 h to make a suspension; then add 0.2 - 1.2 parts of siloxane and 0.02 - 0.04 parts of catalyst to the suspension, and mix and stir at a speed of 150 rpm for 10 min to make a hydrogel; perform ultraviolet curing on the hydrogel, subject the cured hydrogel to a freezing treatment at -40 °C to make an ice product, then crush the ice product to make ice product powder with a diameter of 50 - 100 nm; place the ice product powder in the tray of a freeze dryer and dry it by gradient heating. The total drying time is 15 - 30 h to obtain modified graphene aerogel powder;

[0009] (3) Mix 3 parts of modified graphene aerogel powder, 0.5 - 1.5 parts of titanium dioxide powder with 70 parts of sodium hydroxide solution, stir evenly at a speed of 150 rpm for 20 min, then ultrasonically treat at a power of 50 kHz for 30 min, then keep it warm at 160 - 180 °C for 48 h, filter to obtain the solid, wash it 3 times with deionized water first, then wash it 3 times with hydrochloric acid solution, and finally wash it 3 times with deionized water again, and dry it at normal temperature and pressure for 2 h; then disperse the dried product into a nitric acid aqueous solution with a solid - liquid ratio of 1:100, keep it warm at 100 - 120 °C for 40 h, dry it at normal temperature and pressure for 2 h, and then place it in a muffle furnace for high - temperature treatment at 450 °C for 1 - 3 h to obtain a composite filler;

[0010] (4) Mix terephthalic acid, ethylene glycol, and the composite filler in a mass ratio of 1:0.9 - 1.1:0.1 - 0.3 for esterification reaction and polycondensation reaction. The temperature of the esterification reaction is 180 °C, the pressure is 0.01 MPa, and the time is 2 h; after the esterification reaction, carry out the polycondensation reaction in stages: the temperature of the first - stage polycondensation is 220 °C, the pressure is 0.4 - 0.8 kPa, and the time is 0.5 - 1.5 h; the temperature of the second - stage polycondensation is 240 °C, the pressure is 20 - 80 Pa, and the time is 1 - 3 h; extrude and melt the polycondensed polyester raw material through a screw, change the slurry into hollow - shaped spinning at the spinneret to obtain hollow - shaped fibers. The ejected fibers are quickly shaped by high - speed stretching and air cooling by ring blowing, flow into a reciprocating machine for barrel - collecting and bundling. When the total denier of the composite production reaches 600 denier, perform rapid drawing through an oil - bath tank, then enter a steam box for micro - stretching. The temperature of the steam box is 120 °C, the micro - stretching time is 2 s, carry out three - dimensional curling inside to fully form, then enter a cutting machine for cutting, and then put it into a three - layer oven for heat - setting to make graphene cloud velvet.

[0011] Further, the ball - milling conditions in step (1) are as follows: steel balls with a diameter of 1.2 cm, and the ball - to - material ratio is 6 - 10:1.

[0012] Further, in the step (2), the siloxane is γ-methacryloxypropyltrimethoxysilane.

[0013] Further, in the step (2), the catalyst is N, N, N', N'-tetramethylethylenediamine.

[0014] Further, in the step (2), the ultraviolet curing conditions are as follows: the power of the ultraviolet lamp is 2.4 KW, and the curing time is 2 h.

[0015] Further, in the step (2), the vacuum freeze-drying conditions are as follows: drying is carried out at a partition temperature of -5°C under a vacuum degree of 10 Pa.

[0016] Further, in the step (3), the concentration of the sodium hydroxide aqueous solution is 10 M.

[0017] Further, in the step (3), the concentration of the hydrochloric acid aqueous solution is 0.1 - 0.3 M.

[0018] Further, in the step (3), the concentration of the nitric acid aqueous solution is 0.05 - 0.07 M.

[0019] Further, in the step (4), the heat setting temperature is 180°C.

[0020] Compared with the prior art, the beneficial effects achieved by the present invention are as follows:

[0021] The present invention uses an aerogel made of modified graphene, with silica nanocrystals attached to the surface to form a filler, which is blended with polyester and spun into cloud velvet to achieve the effects of high strength, antibacterial property, and warmth retention.

[0022] First, through chemical bonding, an addition reaction is carried out between 4-aminostyrene and the carbon layer on the surface of graphite flakes to introduce double bonds on the surface of graphene for modification; the modified graphene is mixed with γ-methacryloxypropyltrimethoxysilane to prepare a hydrogel. Under the action of a catalyst, through ultraviolet light irradiation, the double bonds on graphene and the siloxane are polymerized to form a double cross-linked network, and then an aerogel is prepared, maintaining this double network structure. On the one hand, it improves the strength of the cloud velvet, and on the other hand, while not affecting the properties of graphene, it can avoid the agglomeration of graphene in polyester, improve the dispersion of graphene, and further enhance the performance of the cloud velvet; titanium dioxide nanocrystals are attached to the aerogel, and then after hydrothermal reaction, the surface becomes rough and uneven. The octahedra of titanium dioxide on the fiber surface dehydrate during contact with acid and rearrange to form a crystal form transformation that strengthens the porosity. This transformed crystal form causes the photo-generated electrons and holes to transfer through the interface, reducing the recombination rate of photo-generated carriers, improving the photocatalytic activity of titanium dioxide nanocrystals, increasing the concentration of reactive oxygen species generated by its catalysis, and further enhancing its antibacterial property;

[0023] Secondly, cloud velvet is made of polyester hollow profiled spinning to form a penetrating porous structure, which can enrich more static air to improve the warmth retention effect. During the fiber forming process, an all-round annular high-speed strong cold blowing technology is adopted to instantaneously cool the spinning melt rapidly with extremely small errors, resulting in a unique crystallization state of cloud velvet different from other polyester fibers. Its bulk density is very small, and cloud velvet of the same volume is about one-third lighter than other chemical fibers of the same specification. Specific Embodiments

[0024] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0025] In order to more clearly illustrate the method provided by the present invention, the following embodiments are used for detailed description. The test methods for each index of the graphene cloud velvet produced in the following embodiments are as follows:

[0026] Antibacterial property: The antibacterial properties of the examples and comparative examples are tested in accordance with the national standard GB / T20944.3-2008 "Evaluation of Antibacterial Properties of Textiles - Part 3: Oscillation Method". The test bacteria used are Escherichia coli ATCC25922 and Staphylococcus aureus ATCC6538.

[0027] Warmth retention property: The warmth retention properties of the examples and comparative examples are tested in accordance with GB / T11048-2008-T "Determination of Thermal Resistance and Moisture Resistance of Textiles under Steady-State Conditions of Physiological Comfort".

[0028] Strength: The antibacterial properties of the examples and comparative examples are subjected to a breaking strength experiment according to the detection method in the national standard GB / T 3923.1-1997 "Determination of Breaking Strength and Elongation at Break of Textiles - Strip Method for Tensile Properties of Fabrics".

[0029] Example 1: (1) First, weigh 1 part of graphite flakes and 10 parts of sodium chloride for ball milling. Use steel balls with a diameter of 1.2 cm, the ball-to-material ratio is 6:1, and the ball milling time is 0.5 h. Then add 5 parts of p-aminostyrene, mix and continue ball milling for 0.5 h. Finally, add 16 parts of nitrite and mix and ball mill for 24 h. After that, wash twice with deionized water and then vacuum dry at 0.085 MPa and 50 °C to obtain modified graphene;

[0030] (2) Mix 1 part of modified graphene with 50 parts of deionized water, stir at a speed of 350 rpm for 1 h, then ultrasonically treat at 30 kHz for 30 min, and continue to stir for 1 h to make a suspension; then add 0.2 part of γ-methacryloxypropyltrimethoxysilane and 0.02 part of N,N,N',N'-tetramethylethylenediamine to the suspension, and then mix and stir at a speed of 150 rpm for 10 min to make a hydrogel; perform ultraviolet curing on the hydrogel, the power of the ultraviolet lamp is 2.4 KW, and the curing time is 2 h; perform a freezing treatment on the cured hydrogel at -40 °C to make an ice product, and then crush the ice product to make an ice product powder with a diameter of 50 nm; place the ice product powder in the tray of a freeze dryer, and dry it at a partition temperature of -5 °C under a vacuum of 10 Pa, and the total drying time is 15 h to obtain modified graphene aerogel powder;

[0031] (3) Mix 3 parts of modified graphene aerogel powder, 0.5 part of titanium dioxide powder with 70 parts of a sodium hydroxide solution with a concentration of 10 M, stir evenly at a speed of 150 rpm for 20 min, then ultrasonically treat at a power of 50 kHz for 30 min, and then keep it warm at 160 °C for 48 h, filter to obtain the solid, first wash it 3 times with deionized water, then wash it 3 times with a hydrochloric acid solution with a concentration of 0.1 M, and finally wash it 3 times with deionized water, and dry it at normal temperature and pressure for 2 h; then disperse the dried product into a nitric acid aqueous solution with a liquid concentration of 0.05 M, the solid-liquid ratio is 1:100, keep it warm at 100 °C for 40 h, dry it at normal temperature and pressure for 2 h, and then place it in a muffle furnace for high-temperature treatment at 450 °C for 1 h to obtain a composite filler;

[0032] (4) Mix terephthalic acid, ethylene glycol, and the composite filler in a mass ratio of 1:0.9:0.1 for esterification reaction and polycondensation reaction. The temperature of the esterification reaction is 180 °C, the pressure is 0.01 MPa, and the time is 2 h; after the esterification reaction is completed, carry out the polycondensation reaction in stages: the temperature of the first-stage polycondensation is 220 °C, the pressure is 0.4 kPa, and the time is 0.5 h; the temperature of the second-stage polycondensation is 240 °C, the pressure is 20 Pa, and the time is 1 h; extrude and melt the polycondensed polyester raw material through a screw, and change the slurry into hollow profiled spinning at the spinneret to obtain hollow profiled fibers. The ejected fibers are quickly shaped by high-speed stretching and air cooling by ring blowing, and flow into a reciprocating machine for barrel bundling. When the total denier of the composite production reaches 600 denier, perform rapid drawing through an oil bath, and then enter a steam box for micro-drawing. The temperature of the steam box is 120 °C, and the micro-drawing time is 2 s. Perform three-dimensional curling inside to fully form, and then enter a cutting machine for cutting, and then put it into a three-layer oven for heat setting. The heat setting temperature is 180 °C to make graphene cloud velvet.

[0033] Example 2; (1) First, weigh 1 part of graphite flakes and 10 parts of sodium chloride and perform ball milling with 1.2 cm steel balls, a ball-to-material ratio of 8:1, and a ball milling time of 1 h; then add 7.5 parts of p-aminostyrene, mix and continue ball milling for 1 h; finally, add 18 parts of nitrite and mix and ball mill for 24 h. After completion, wash twice with deionized water and then vacuum dry at 0.085 MPa and 50 °C to obtain modified graphene;

[0034] (2) Mix 3 parts of modified graphene with 50 parts of deionized water, stir at a speed of 350 rpm for 1.5 h, then perform ultrasonic treatment at 30 kHz for 30 min, and continue to stir for 1.5 h to prepare a suspension; then add 0.6 part of γ-methacryloxypropyltrimethoxysilane and 0.03 part of N,N,N',N'-tetramethylethylenediamine to the suspension, and mix and stir at a speed of 150 rpm for 10 min to prepare a hydrogel; perform ultraviolet curing on the hydrogel, with the power of the ultraviolet lamp being 2.4 KW and the curing time being 2 h; subject the cured hydrogel to freezing treatment at -40 °C to make an ice product, then crush the ice product to make ice product powder with a diameter of 75 nm; place the ice product powder in the tray of a freeze dryer and dry at a vacuum degree of 10 Pa and a partition temperature of -5 °C, with the total drying time being 23 h, to obtain modified graphene aerogel powder;

[0035] (3) Mix 3 parts of modified graphene aerogel powder, 1 part of titanium dioxide powder with 70 parts of a 10 M sodium hydroxide solution, stir evenly at a speed of 150 rpm for 20 min, then perform ultrasonic treatment at a power of 50 kHz for 30 min, then keep warm at 170 °C for 48 h, filter to obtain the solid, first wash 3 times with deionized water, then wash 3 times with a 0.2 M hydrochloric acid solution, and finally wash 3 times with deionized water again, and dry at normal temperature and pressure for 2 h; then disperse the dried product into a 0.06 M nitric acid aqueous solution with a solid-liquid ratio of 1:100, keep warm at 110 °C for 40 h, dry at normal temperature and pressure for 2 h, and then place it in a muffle furnace for high-temperature treatment at 450 °C for 2 h to obtain the composite filler;

[0036] (4)Terephthalic acid, ethylene glycol, and composite filler are mixed in a mass ratio of 1:1:0.2 for esterification reaction and polycondensation reaction. The temperature of the esterification reaction is 180°C, the pressure is 0.01 MPa, and the time is 2 h. After the esterification reaction, the polycondensation reaction is carried out in stages: the temperature of the first-stage polycondensation is 220°C, the pressure is 0.6 kPa, and the time is 1 h; the temperature of the second-stage polycondensation is 240°C, the pressure is 50 Pa, and the time is 2 h. The polycondensed polyester raw material is extruded and melted by a screw, and the slurry is changed into hollow profiled spinning at the spinneret to obtain hollow profiled fibers. The ejected fibers are quickly shaped by high-speed stretching and ring blow air cooling, and then flow into a reciprocating machine for barrel bundling. When the total denier of the composite production reaches 600 denier, it is quickly drawn through an oil bath, and then enters a steam box for micro-stretching. The temperature of the steam box is 120°C, and the micro-stretching time is 2 s. Three-dimensional curling is fully formed inside, and then it enters a cutting machine for cutting. After cutting, it is put into a three-layer oven for heat setting. The heat setting temperature is 180°C to make graphene cloud velvet.

[0037] Example 3; (1) First, weigh 1 part of graphite flakes and 10 parts of sodium chloride for ball milling. Use steel balls with a diameter of 1.2 cm, the ball-to-material ratio is 10:1, and the ball milling time is 1.5 h. Then add 10 parts of p-aminostyrene, mix and continue ball milling for 1.5 h. Finally, add 20 parts of nitrite and mix and ball mill for 24 h. After that, wash it twice with deionized water and then vacuum dry it at 0.085 MPa and 50°C to obtain modified graphene.

[0038] (2)Mix 5 parts of modified graphene with 50 parts of deionized water, stir at a speed of 350 rpm for 2 h, then perform ultrasonic treatment at 30 kHz for 30 min, and continue to stir for 2 h to make a suspension. Then add 1.2 parts of γ-methacryloxypropyltrimethoxysilane and 0.04 part of N,N,N',N'-tetramethylethylenediamine to the suspension, and mix and stir at a speed of 150 rpm for 10 min to make a hydrogel. Perform ultraviolet curing on the hydrogel. The power of the ultraviolet lamp is 2.4 KW, and the curing time is 2 h. Freeze the cured hydrogel at -40°C to make an ice product, and then crush the ice product to make ice product powder with a diameter of 100 nm. Put the ice product powder into the tray of a freeze dryer and dry it at a vacuum degree of 10 Pa and a partition temperature of -5°C. The total drying time is 30 h to obtain modified graphene aerogel powder.

[0039] (3) Mix 3 parts of modified graphene aerogel powder, 1.5 parts of titanium dioxide powder with 70 parts of sodium hydroxide solution with a concentration of 10 M. After stirring evenly at a speed of 150 rpm for 20 min, ultrasonic wave for 30 min at a power of 50 kHz, then keep warm at 180 °C for 48 h. Filter to obtain the solid, wash it with deionized water 3 times first, then wash it with hydrochloric acid solution with a concentration of 0.3 M 3 times, and finally wash it with deionized water 3 times again. Dry it at normal temperature and pressure for 2 h; then disperse the dried product into a nitric acid aqueous solution with a liquid concentration of 0.07 M, and the solid-liquid ratio is 1:100. Keep warm at 120 °C for 40 h, dry it at normal temperature and pressure for 2 h, and then place it in a muffle furnace for high-temperature treatment at 450 °C for 3 h to obtain the composite filler;

[0040] (4) Carry out esterification reaction and polycondensation reaction by mixing terephthalic acid, ethylene glycol and the composite filler according to a mass ratio of 11.1:0.3. The temperature of the esterification reaction is 180 °C, the pressure is 0.01 MPa, and the time is 2 h; after the esterification reaction is completed, carry out polycondensation reaction in stages: the temperature of the first-stage polycondensation is 220 °C, the pressure is 0.8 kPa, and the time is 1.5 h; the temperature of the second-stage polycondensation is 240 °C, the pressure is 80 Pa, and the time is 3 h; extrude and melt the polycondensed polyester raw material through a screw, and change the slurry into hollow profiled spinning at the spinneret to obtain hollow profiled fibers. The ejected fibers are quickly shaped by high-speed stretching and air cooling by ring blowing, and flow into a reciprocating machine for barrel bundling. When the total denier of the composite production reaches 600 denier, carry out rapid drawing through an oil bath, and then enter a steam box for micro-drawing. The temperature of the steam box is 120 °C, and the micro-drawing time is 2 s. Carry out three-dimensional curling inside to fully form, and then enter a cutting machine for cutting. After cutting, put it into a three-layer oven for heat setting. The heat setting temperature is 180 °C to make graphene cloud velvet.

[0041] Comparative Example 1; The difference between Comparative Example 1 and Example 2 is that step (1) is not carried out, and step (2) is changed to: Mix 3 parts of graphene with 50 parts of deionized water, stir at a speed of 350 rpm for 1.5 h, and then continue to stir for 1.5 h after ultrasonic treatment at 30 kHz for 30 min to make a suspension; then add 0.6 part of γ-methacryloxypropyltrimethoxysilane and 0.03 part of N, N, N', N'-tetramethylethylenediamine to the suspension, and then mix and stir at a speed of 150 rpm for 10 min to make a hydrogel; carry out ultraviolet curing on the hydrogel. The power of the ultraviolet lamp is 2.4 KW, and the curing time is 2 h; carry out freezing treatment at -40 °C on the cured hydrogel to make an ice product, and then crush the ice product to make ice product powder with a diameter of 75 nm; put the ice product powder into the tray of a freeze dryer, and dry it at a vacuum degree of 10 Pa and a partition temperature of -5 °C. The total drying time is 23 h to obtain the modified graphene aerogel powder; the remaining steps are the same as those in Example 2.

[0042] Comparative Example 2; The difference between Comparative Example 2 and Example 2 lies in the difference in step (2). Step (3) is changed to: Mix 3 parts of modified graphene with 50 parts of deionized water, stir at a speed of 350 rpm for 1.5 h, then perform ultrasonic treatment at 30 kHz for 30 min, and continue to stir for 1.5 h to prepare a suspension; Then add 0.03 parts of N, N, N', N'-tetramethylethylenediamine to the suspension, and mix and stir at a speed of 150 rpm for 10 min to prepare a hydrogel; Perform ultraviolet curing on the hydrogel, the power of the ultraviolet lamp is 2.4 KW, and the curing time is 2 h; Freeze the cured hydrogel at -40 °C to make an ice product, then crush the ice product to make ice product powder with a diameter of 75 nm; Place the ice product powder in the tray of a freeze dryer, and dry it at a partition temperature of -5 °C under a vacuum of 10 Pa, and the total drying time is 23 h to obtain modified graphene aerogel powder; The remaining steps are the same as those in Example 2.

[0043] Comparative Example 3; The difference between Comparative Example 3 and Example 2 is that there is no step (3). Step (4) is changed to: Mix terephthalic acid, ethylene glycol, and modified graphene aerogel powder in a mass ratio of 1:1:0.2 for esterification reaction and polycondensation reaction. The temperature of the esterification reaction is 180 °C, the pressure is 0.01 MPa, and the time is 2 h; After the esterification reaction, perform polycondensation reaction in stages: the temperature of the first-stage polycondensation is 220 °C, the pressure is 0.6 kPa, and the time is 1 h; The temperature of the second-stage polycondensation is 240 °C, the pressure is 50 Pa, and the time is 2 h; Extrude and melt the polycondensed polyester raw material through a screw, and change the slurry into hollow profiled spinning at the spinneret to obtain hollow profiled fibers. The ejected fibers are quickly shaped by high-speed stretching and ring blowing air cooling, and flow into a reciprocating machine for barrel bundling. When the total denier of the composite production reaches 600 denier, perform rapid drawing through an oil bath, and then enter a steam box for micro-stretching. The temperature of the steam box is 120 °C, and the micro-stretching time is 2 s. Perform three-dimensional curling inside to fully form, and then enter a cutting machine for cutting. After cutting, place it in a three-layer oven for heat setting. The heat setting temperature is 180 °C to make graphene cloud velvet; The remaining steps are the same as those in Example 2.

[0044] Comparative Example 4; The difference between Comparative Example 4 and Example 2 lies in step (3). Step (3) is changed to: Mix 3 parts of modified graphene aerogel powder, 1 part of titanium dioxide powder with 70 parts of sodium hydroxide solution with a concentration of 10 M, stir evenly at a speed of 150 rpm for 20 min, then ultrasonic for 30 min at a power of 50 kHz, then keep warm at 170 °C for 48 h, filter to obtain the solid, wash it 3 times with deionized water first, then wash it 3 times with hydrochloric acid solution with a concentration of 0.2 M, and finally wash it 3 times with deionized water again, and dry it at normal temperature and pressure for 2 h to obtain the composite filler; the remaining steps are the same as those in Example 2.

[0045] Comparative Example 5; The difference between Comparative Example 5 and Example 2 lies in step (4). Step (4) is changed to: Mix terephthalic acid, ethylene glycol, and the composite filler in a mass ratio of 1:1:0.2 for esterification reaction and polycondensation reaction. The temperature of the esterification reaction is 180 °C, the pressure is 0.01 MPa, and the time is 2 h; after the esterification reaction is completed, the polycondensation reaction is carried out in stages: the temperature of the first-stage polycondensation is 220 °C, the pressure is 0.6 kPa, and the time is 1 h; the temperature of the second-stage polycondensation is 240 °C, the pressure is 50 Pa, and the time is 2 h; the polycondensed polyester raw material is extruded and melted by a screw, the slurry is changed into cloud velvet silk at the spinneret, and the ejected fibers are quickly shaped by high-speed stretching and ring blowing air cooling, and then flow into a reciprocating machine for barrel bundling. When the total denier of the composite production reaches 600 denier, it is quickly drawn through an oil bath, and then enters a steam box for micro-stretching. The temperature of the steam box is 120 °C, the micro-stretching time is 2 s, and three-dimensional curling is fully formed inside, and then it enters a cutting machine for cutting, and then is put into a three-layer oven for heat setting. The heat setting temperature is 180 °C to make graphene cloud velvet; the remaining steps are the same as those in Example 2.

[0046] Effect Example

[0047] The performance analysis results of the graphene cloud velvet using Examples 1 to 3 and Comparative Examples 1 to 5 of the present invention are given in Table 1 below.

[0048] Table 1

[0049]

[0050] From the comparison of the experimental data on the fracture strength of the examples and the comparative examples, it can be found that in the present invention, p-aminostyrene is subjected to an addition reaction with the carbon layer on the surface of graphite flakes through chemical bonding, and double bonds are introduced on the surface of graphene for modification; the modified graphene is mixed with γ-methacryloxypropyltrimethoxysilane to prepare a hydrogel, and under the action of a catalyst, the double bonds on the graphene and the siloxane are polymerized by ultraviolet light irradiation to form a double cross-linked network, and then an aerogel is prepared to maintain this double network structure. On the one hand, it improves the strength of the cloud fluff, and on the other hand, while not affecting the properties of graphene, it can avoid the agglomeration of graphene in polyester, improve the dispersion of graphene, and further enhance the performance of the cloud fluff; from the comparison of the experimental data on the antibacterial property of the examples and the comparative examples, it can be found that in the present invention, titanium dioxide nanocrystals are attached to the aerogel, and then the surface becomes rough and uneven after hydrothermal reaction. The octahedra of titanium dioxide on the fiber surface dehydrate during contact with an acid and rearrange to form a crystal form transformation that strengthens the porosity. This transformed crystal form causes the photo-generated electrons and holes to transfer through the interface, reducing the recombination rate of photo-generated carriers and improving the photocatalytic activity of the titanium dioxide nanocrystals, resulting in an increase in the concentration of reactive oxygen species generated by its catalysis and further improving its antibacterial performance; from the comparison of the experimental data on the heat preservation property of the examples and the comparative examples, it can be found that in the present invention, polyester hollow profiled spinning is used to form a through-hole structure, which can enrich more static air to improve the heat preservation effect; during the fiber forming process, an all-round annular high-speed strong cold air blowing technology is adopted to quickly cool the spinning melt instantly with extremely small errors, resulting in a unique crystallization state of the cloud fluff different from other polyester fibers, and its bulk density is very small. The cloud fluff of the same volume is about one-third lighter than other chemical fibers of the same specification.

[0051] 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 construed as limiting the claimed claim.

Claims

1. A method for preparing graphene cloud velvet, characterized in that: The method comprises the following preparation steps: (1) First, weigh 1 part of graphite flakes and 10 parts of sodium chloride for ball milling for 0.5-1.5 hours; then add 5-10 parts of p-aminostyrene, mix and ball mill for 0.5-1.5 hours; finally, add 16-20 parts of nitrite and mix and ball mill for 24 hours, then wash twice with deionized water, and then vacuum dry at 0.085 MPa and 50°C to obtain modified graphene; (2) Mixing 1-5 parts of modified graphene with 50 parts of deionized water, stirring at 350 rpm for 1-2 hours, and then subjecting the mixture to 30 kHz ultrasonic treatment for 30 minutes, and then continuing to stir for 1-2 hours to prepare a suspension; adding 0.2-1.2 parts of γ-methacryloxypropyltrimethoxysilane and 0.02-0.04 parts of N,N,N',N'-tetramethylethylenediamine to the suspension, and then stirring the mixture at 150 rpm for 10 minutes to prepare a hydrogel; UV curing the hydrogel, freezing the cured hydrogel at -40°C to prepare an ice product, and then crushing the ice product to prepare an ice product powder with a diameter of 50-100 nm; placing the ice product powder in a freeze dryer tray, drying it with a gradient temperature increase, and the entire drying time is 15-30 hours to prepare a modified graphene aerogel powder; (3) Mix 3 parts of modified graphene aerogel powder, 0.5-1.5 parts of titanium dioxide powder and 70 parts of sodium hydroxide solution, stir at 150 rpm for 20 minutes, ultrasonicate at 50 kHz for 30 minutes, and then keep warm at 160-180°C for 48 hours. Filter the solid, wash it with deionized water for 3 times, then wash it with hydrochloric acid solution for 3 times, and finally wash it with deionized water for 3 times, and dry it at room temperature and pressure for 2 hours. Then disperse the dried product into nitric acid aqueous solution with a solid-liquid ratio of 1:100, keep warm at 100-120°C for 40 hours, dry it at room temperature and pressure for 2 hours, and then place it in a Mabo furnace for high temperature treatment at 450°C for 1-3 hours to obtain a composite filler. (4) Terephthalic acid, ethylene glycol and composite filler are mixed in a mass ratio of 1:0.9-1.1:0.1-0.3 for esterification reaction and polycondensation reaction. The temperature of the esterification reaction is 180°C, the pressure is 0.01MPa and the time is 2h. After the esterification reaction is completed, the polycondensation reaction is carried out in stages: the first stage polycondensation temperature is 220°C, the pressure is 0.4-0.8kPa and the time is 0.5-1.5h; the second stage polycondensation temperature is 240°C, the pressure is 20-80Pa and the time is 1-3h. The polyester raw material after polycondensation is passed through a screw After extrusion and melting, the slurry is transformed into hollow shaped spinning at the spinneret to obtain hollow shaped fibers. The ejected fibers are quickly shaped by high-speed stretching and ring-blown air cooling, and flow into the reciprocating machine for barrel bundling. When the bundling reaches a total denier of 600 deniers for composite production, it is quickly stretched through an oil bath, and then enters the steam box for micro-stretching. The steam box temperature is 120°C, and the micro-stretching time is 2s. Three-dimensional curling is performed inside to fully form the fibers, and then the fibers enter the cutting machine for cutting. After cutting, they are placed in a three-layer oven for heat setting to make graphene cloud velvet.

2. The method for preparing graphene cloud velvet according to claim 1, characterized in that: The ball milling conditions in step (1) are: 1.2 cm steel balls, and a ball-to-material ratio of 6-10:

1.

3. The method for preparing graphene cloud velvet according to claim 1, characterized in that: The UV curing conditions in step (2) are: the power of the UV lamp is 2.4 kW, and the curing time is 2 h.

4. The method for preparing graphene cloud velvet according to claim 1, characterized in that: The vacuum freeze-drying conditions in step (2) are: drying at a vacuum degree of 10 Pa and a partition temperature of -5°C.

5. The method for preparing graphene cloud velvet according to claim 1, characterized in that: The concentration of the sodium hydroxide aqueous solution in step (3) is 10M.

6. The method for preparing graphene cloud velvet according to claim 1, characterized in that: The concentration of the hydrochloric acid aqueous solution in step (3) is 0.1-0.3M.

7. The method for preparing graphene cloud velvet according to claim 1, characterized in that: The concentration of the nitric acid aqueous solution in step (3) is 0.05-0.07M.

8. The method for preparing graphene cloud velvet according to claim 1, characterized in that: The heat setting temperature in step (4) is 180°C.

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