Negative ion polyester fiber and preparation method thereof

Abstract

The invention relates to the technical field of polyester fibers, in particular to a negative ion polyester fiber which is prepared from the following raw materials in percentage by mass: 85-92% of polyethylene glycol terephthalate, 3-8% of nano tourmaline composite powder, 2-5% of a titanium dioxide / graphene composite carrier, 0.5-1.5% of a coupling agent and 0.3-0.8% of an antioxidant. The invention also discloses a preparation method of the composition. According to the invention, the core-shell structure optimization design is adopted, the core layer ensures the high loading capacity of the tourmaline composite powder, the shell layer has the synergistic effect of the titanium dioxide / graphene composite carrier, the negative ion release efficiency is obviously enhanced, the particle size of the nanoscale tourmaline is controlled to be 50-100nm, the nanoscale tourmaline is uniformly dispersed, the nanoscale tourmaline and graphene form a heterojunction structure, and the electron transmission capability is greatly improved; the negative ion release amount meets the JIS standard, a chemical bonding interface is formed through transesterification, the structural stability is enhanced, and the retention rate of the negative ion release performance is still high even after multiple times of washing.

Description

TECHNICAL FIELD

[0001] The present application relates to the polyester fiber technical field, especially a kind of negative ion polyester fiber and preparation method thereof. BACKGROUND

[0002] Traditional polyester fiber takes polyethylene terephthalate as base material, with high strength, wear resistance and chemical stability, but single function, lack of negative ion release, antibacterial, anti-ultraviolet and other additional functions.The existing negative ion fiber technology mainly realizes negative ion release by adding tourmaline powder;

[0003] In prior art, nano tourmaline particle size is too large or too small, dispersibility is poor, easy to agglomerate, affect negative ion release efficiency.

[0004] Based on this, the present application designs a kind of negative ion polyester fiber and preparation method thereof, to solve the above problems. SUMMARY

[0005] The present application provides a kind of negative ion polyester fiber and preparation method thereof to solve the above technical deficiencies, and the polyester fiber prepared can release negative ions stably, and release efficiency is high.

[0006] The present application discloses a kind of negative ion polyester fiber, which is composed of the following mass percentage raw materials:

[0007] Polyethylene terephthalate: 85-92%,

[0008] Nano tourmaline composite powder: 3-8%,

[0009] Titanium dioxide / graphene composite carrier: 2-5%,

[0010] Coupling agent: 0.5-1.5%,

[0011] Antioxidant: 0.3-0.8%,

[0012] The nano tourmaline composite powder is a composite of magnesium iron tourmaline and germanite with a particle size of 50-100 nm in a mass ratio of 3:1.

[0013] The polyethylene terephthalate is the basic component of polyester fiber, providing the basic skeleton and physical properties of the fiber. Within this range, the fiber has good strength, toughness and processing properties. If the content is less than 85%, the basic properties of the fiber may be affected, and the strength and toughness may decrease. If the content is higher than 92%, the proportion of other functional components is relatively reduced, which may affect the negative ion release function.

[0014] Nanometer tourmaline composite powder is the key ingredient for generating negative ions. Its content in this range can ensure the effective release of negative ions and good mixing with other ingredients during fiber preparation. If the content is too low, the amount of negative ion release will be insufficient; if the content is too high, it may affect the spinnability of the fiber and other properties;

[0015] Titanium dioxide / graphene composite carrier helps to improve the release efficiency and stability of negative ions, and may also endow the fiber with other functions such as antibacterial and anti-ultraviolet properties. The content between 2-5% can fully exert its synergistic effect without affecting the main properties of the fiber;

[0016] Coupling agent is used to improve the interfacial bonding between ingredients, so that different raw materials can be better mixed and dispersed, and the overall performance of the fiber can be improved. If the content is too low, the interfacial bonding effect will be poor; if the content is too high, impurities may be introduced, affecting the quality of the fiber;

[0017] Antioxidants can prevent the fiber from being oxidized during processing and use, prolonging the service life of the fiber. The content in the range of 0.3-0.8% can effectively play an antioxidant role without significantly affecting other properties of the fiber;

[0018] Selecting magnesium-iron tourmaline with a particle size of 50-100 nm is beneficial to its uniform dispersion in the fiber and improves the release efficiency of negative ions. Ge-stone with a particle size of 50-100 nm is compounded with magnesium-iron tourmaline at a mass ratio of 3:1, which can produce a synergistic effect and enhance the generation and release of negative ions.

[0019] The polyester fiber adopts a core-shell structure, in which:

[0020] The core layer is a polyester master batch containing nanometer tourmaline composite powder, with a diameter of 60-70% of the diameter of the polyester fiber, to ensure that the nanometer tourmaline composite powder occupies enough space in the fiber to achieve sustained and stable release of negative ions; the core layer diameter ratio in this range can ensure that the nanometer tourmaline composite powder occupies enough space in the fiber to release negative ions continuously and stably. If the diameter ratio is too small, the amount of negative ion release may be insufficient; if the diameter ratio is too large, it may affect the function of the shell layer and the overall performance of the fiber;

[0021] The shell layer is a copolyester layer doped with titanium dioxide / graphene composite carrier, with a thickness of 1-2 μm to balance the need for protecting the core layer and exerting the synergistic effect of titanium dioxide / graphene composite carrier; the shell layer thickness between 1-2 μm can effectively protect the core layer and make the titanium dioxide / graphene composite carrier fully exert its function, such as improving the release efficiency of negative ions and enhancing other properties of the fiber. If the thickness is too thin, the protection and synergistic effect may be insufficient; if the thickness is too thick, it may increase the cost of the fiber and affect its hand feeling and other properties;

[0022] The core-shell interface is chemically bonded through ester exchange reaction to enhance the binding force between the core layer and the shell layer and improve the structural stability of the fiber.

[0023] A preparation method of a negative ion polyester fiber, comprising the following steps:

[0024] Step 1, master batch preparation: melt blend nano tourmaline composite powder, polyethylene terephthalate and antioxidant at 280-300 DEG C, and granulate by a double screw extruder; the temperature is controlled at 280-300 DEG C, so that the nano tourmaline composite powder and polyethylene terephthalate can be fully melt mixed, while avoiding decomposition or performance degradation of raw materials due to excessively high temperature, and the double screw extruder granulation can make the particle size of the master batch uniform, which is beneficial to the subsequent spinning process;

[0025] Step 2, shell treatment: ultrasonic dispersion of titanium dioxide / graphene composite carrier and coupling agent in ethanol solution for 30 min, and grafting to copolyester segment by in-situ polymerization; the specific surface area of the titanium dioxide / graphene composite carrier is ≥200 m 2 / g, which has a large active surface and is beneficial to reaction with the coupling agent and the copolyester segment, and ultrasonic dispersion for 30 min can make the composite carrier uniformly dispersed in the ethanol solution, improving the grafting effect;

[0026] Step 3, composite spinning: using a skin-core composite spinning machine, the core layer feeding temperature is 290-300 DEG C, the shell layer feeding temperature is 275-285 DEG C, and the spinning speed is 2800-3200 m / min; different feeding temperatures are set for the core layer and the shell layer to adapt to the characteristics of the respective raw materials and ensure the smooth progress of the spinning process, the higher core layer temperature is beneficial to the full melting of the polyester master batch of nano tourmaline composite powder; the relatively lower shell layer temperature can prevent excessive degradation of the copolyester, and the spinning speed is controlled at 2800-3200 m / min to ensure the forming quality and production efficiency of the fiber;

[0027] Step 4, post-treatment: the fiber is drawn by 3-5% citric acid aqueous solution, the setting temperature is 110-130 DEG C, and the oiling rate is controlled at 0.6-1.2%; the drawing by 3-5% citric acid aqueous solution can improve the orientation and mechanical properties of the fiber, the setting temperature of 110-130 DEG C can make the structure of the fiber more stable, and improve its dimensional stability, the oiling rate controlled at 0.6-1.2% can improve the hand feeling and spinnability of the fiber, and prevent static electricity and other problems during subsequent processing and use.

[0028] The preparation method of the titanium dioxide / graphene composite carrier comprises:

[0029] (1) mixing graphene oxide with layer number ≤5 layers and nano titanium dioxide with particle size 20-30 nm at a mass ratio of 1:2;

[0030] (2) The heterojunction structure is formed by hydrothermal reaction (180℃ / 12h) under nitrogen protection, and the specific surface area is 220-250m 2 / g.

[0031] The graphene oxide with the layer number less than 5 has a large specific surface area and good electron transmission performance. The nano titanium dioxide with a particle size of 20-30nm is beneficial to uniform mixing with the graphene oxide and formation of the heterojunction structure. The best synergistic effect can be generated by mixing according to the mass ratio of 1:2, and the performance of the composite carrier is improved. The hydrothermal reaction (180℃ / 12h) under nitrogen protection can prevent oxidation of raw materials and ensure formation of the heterojunction structure. The composite carrier with a specific surface area of 220-250m 2 / g has high activity and good performance, and is beneficial to improvement of the performance of the anion polyester fiber.

[0032] The performance indexes of the anion polyester fiber obtained by the method include:

[0033] The anion release amount is greater than or equal to 5000 ions / cm 3 (JIS B9929 standard);

[0034] The anion retention rate is greater than or equal to 85% after 50 times of standard washing;

[0035] The breaking strength is greater than or equal to 4.2 cN / dtex;

[0036] The curl elastic recovery rate is greater than or equal to 92%.

[0037] The anion polyester fiber and the preparation method thereof have the following beneficial effects:

[0038] 1. The core-shell structure is optimized and designed, the core layer ensures high loading of tourmaline composite powder, the shell layer has the synergistic effect of titanium dioxide / graphene carrier, the anion release efficiency is significantly enhanced, the nano tourmaline particle size is controlled in the range of 50-100nm, the tourmaline is uniformly dispersed and forms a heterojunction structure with graphene, the electron transmission capacity is greatly improved, the anion release amount meets the JIS standard, the chemical bonding interface is formed through the ester exchange reaction, the structural stability is enhanced, and even after multiple washing, the anion release performance retention rate is still high.

[0039] 2. The PET is used as a matrix to ensure that the fiber has good strength and toughness, fully meets the spinning processing requirements, the shell layer thickness is accurately controlled in the range of 1-2um, the synergistic effect with the functional carrier is realized while the core layer is protected, the problems of hand feeling decline and cost increase caused by the too thick shell layer are effectively avoided, and the performance and experience are double optimized.

[0040] 3. The synergistic effect of titanium dioxide / graphene carrier is used to give the fiber antibacterial, anti-ultraviolet and other additional functions. The appropriate coupling agent improves the interface bonding, and the antioxidant prolongs the service life. The whole process is highly compatible with the traditional polyester fiber production, and is convenient for industrialized application.

[0041] 4. The core layer master batch is granulated by a double screw extruder to ensure uniform dispersion of tourmaline and effectively avoid high temperature decomposition. The shell layer adopts ethanol ultrasonic dispersion and in-situ polymerization process to realize efficient combination of the carrier and copolyester, and significantly improve the grafting efficiency. In the post-processing stage, citric acid solution is used for drawing to improve the fiber orientation, and the setting temperature and oiling rate are precisely controlled to realize good balance of fiber strength and elasticity. DETAILED DESCRIPTION

[0042] In order to further illustrate the technical means and effects adopted by the present application to achieve the predetermined object, the specific embodiments, structures, features and effects according to the present application will be described in detail as follows.

[0043] Example 1:

[0044] The application discloses a preparation method of negative ion polyester fiber.

[0045] Raw material preparation: according to the proportion, polyethylene terephthalate (PET) 92%, nano tourmaline composite powder 5% (mass ratio of magnesioferri tourmaline to germanite 3:1), titanium dioxide / graphene composite carrier with specific surface area of 230 m 2 / g 4%, coupling agent 0.8% and antioxidant 0.2% are weighed.

[0046] Ester exchange interface treatment: the PET of the core layer and the titanium dioxide / graphene composite carrier of the shell layer are placed in a reaction container, and an ester exchange reaction is carried out under the action of a catalyst. Through the ester exchange reaction, a chemical bond is formed between the PET of the core layer and the carrier of the shell layer, thereby enhancing the stability of the fiber core-shell structure. The nano tourmaline composite powder of the core layer and the polyethylene terephthalate are melt blended and extruded to form particles at 290°C.

[0047] Spinning forming: the mixture after ester exchange interface treatment is melt spun. In the spinning process, the core layer feeding temperature is 295°C, the shell layer feeding temperature is 280°C, and the spinning speed is 2900 m / min, so that the melt passes through the spinneret to form a fiber, wherein the shell layer thickness is 2 μm, and the core layer diameter accounts for 60%.

[0048] Post-processing:

[0049] Surface treatment, the spun fiber is placed in citric acid solution for drawing treatment. The citric acid solution can improve the smoothness of the fiber surface, remove impurities and uneven parts on the surface, so as to ensure the uniformity and strength of the fiber.

[0050] Setting and oiling, the fiber after drawing treatment in the citric acid solution is subjected to setting treatment, and the oiling rate is adjusted, the setting temperature is 120 DEG C, and the oiling rate is 0.8%. By balancing the setting temperature and the oiling rate, the fiber has certain strength and good elasticity.

[0051] Example 2:

[0052] The application discloses a preparation method of anion polyester fiber.

[0053] Raw material preparation: according to the proportion, polyethylene terephthalate (PET) 85%, nano tourmaline composite powder 8% (mass ratio of magnesioferri-elbaite to germanite 3:1), titanium dioxide / graphene composite carrier with a specific surface area of 230 m 2 / g 4%, coupling agent 1.5% and antioxidant 1.5% are weighed.

[0054] Ester exchange interface treatment: the PET of the core layer and the titanium dioxide / graphene composite carrier of the shell layer are placed in a reaction container, and ester exchange reaction is carried out under the action of a catalyst. The nano tourmaline composite powder of the core layer and the polyethylene terephthalate are melt blended and extruded at 285 DEG C.

[0055] Spinning forming: the mixture after the ester exchange interface treatment is melt spun. In the spinning process, the core layer feeding temperature is 290 DEG C, the shell layer feeding temperature is 275 DEG C, and the spinning speed is 2800 m / min, so that the melt passes through the spinneret to form the fiber, the shell layer thickness is 1.5 um, and the core layer diameter accounts for 65%.

[0056] Post-treatment:

[0057] Surface treatment, the spun fiber is placed in citric acid solution for drawing treatment. The citric acid solution can improve the smoothness of the fiber surface, remove impurities and uneven parts on the surface, so as to ensure the uniformity and strength of the fiber.

[0058] Setting and oiling, the fiber after drawing treatment in the citric acid solution is subjected to setting treatment, and the oiling rate is adjusted, the setting temperature is 115 DEG C, and the oiling rate is 1%. By balancing the setting temperature and the oiling rate, the fiber has certain strength and good elasticity.

[0059] Example 3:

[0060] The application discloses a preparation method of anion polyester fiber.

[0061] Raw material preparation: polyethylene terephthalate (PET) 90%, nano-tourmaline composite powder 5% (mass ratio of dravite to germanite 3:1), titanium dioxide / graphene composite carrier with specific surface area 230 m 2 / g 3%, coupling agent 1%, and antioxidant 1%.

[0062] Interfacial ester exchange treatment: place the PET of the core layer and the titanium dioxide / graphene composite carrier of the shell layer in a reaction container and perform ester exchange reaction under the action of a catalyst. The nano-tourmaline composite powder of the core layer and the polyethylene terephthalate are melt blended and extruded at 295°C to form granules.

[0063] Spinning forming: melt spinning the mixture after interfacial ester exchange treatment. During the spinning process, the core layer feeding temperature is 295°C, the shell layer feeding temperature is 280°C, and the spinning speed is 3100 m / min, so that the melt passes through the spinneret to form fibers, the shell layer thickness is 1 μm, and the core layer diameter accounts for 70%.

[0064] Post-processing:

[0065] Surface treatment: the spun fiber is placed in a citric acid solution for drawing treatment. The citric acid solution can improve the smoothness of the fiber surface, remove impurities and uneven parts on the surface, so as to ensure the uniformity and strength of the fiber.

[0066] Setting and oiling: the fiber after drawing treatment in the citric acid solution is subjected to setting treatment, and the oiling rate is adjusted, the setting temperature is 125°C, and the oiling rate is 1.1%. By balancing the setting temperature and the oiling rate, the fiber has certain strength and good elasticity.

[0067] Comparative Example 1:

[0068] Raw material preparation: polyethylene terephthalate (PET) 92%, nano-tourmaline composite powder 5% (particle size 50-100 nm, mass ratio of dravite to germanite 3:1), titanium dioxide / graphene composite carrier with specific surface area 230 m 2 / g 4%, coupling agent 0.8%, and antioxidant 0.2%.

[0069] Mixing: directly put all the weighed raw materials into the mixing equipment for sufficient mixing to make the raw materials uniformly dispersed.

[0070] Melt spinning: melt spin the mixed raw materials. Since no interfacial ester exchange treatment is performed, the fiber does not have a core-shell structure. During the spinning process, the melt passes through the spinneret to form fibers.

[0071] Comparative Example 2:

[0072] Raw material preparation: take polyethylene terephthalate (PET) 92%, tourmaline composite powder 5% (particle size above 100 nm, ratio of magnesio-ferri tourmaline to dravite 3:1), titanium dioxide / graphene composite carrier with specific surface area of 230 m 2 / g 4%, coupling agent 0.8% and antioxidant 0.2%.

[0073] Ester exchange interface treatment: the PET in the core layer and the titanium dioxide / graphene composite carrier in the shell layer are subjected to ester exchange reaction to form chemical bonds and enhance structural stability.

[0074] Spinning forming: melt spinning is carried out to form the fiber.

[0075] Post-processing: as in Example 1, citric acid solution drawing treatment, setting and oiling treatment are carried out to improve the surface and performance of the fiber.

[0076] Comparative Example 3:

[0077] Raw material preparation: take polyethylene terephthalate (PET) 92%, nanometer tourmaline composite powder 5% (particle size 50-100 nm, ratio of magnesio-ferri tourmaline to dravite 3:1), pure nanometer titanium dioxide with particle size of 20-30 nm 4% (instead of composite carrier), coupling agent 0.8% and antioxidant 0.2%.

[0078] Ester exchange interface treatment: the PET in the core layer and the pure nanometer titanium dioxide in the shell layer are subjected to ester exchange reaction to form chemical bonds and enhance structural stability.

[0079] Spinning forming: melt spinning is carried out to form the fiber.

[0080] Post-processing: as in Example 1, the spun fiber is subjected to citric acid solution drawing treatment, setting and oiling treatment to improve the quality and performance of the fiber

[0081] Specific detection method for product performance.

[0082] Negative ion release amount detection method:

[0083] Air ion measurement instrument is usually used for detection. This instrument can collect and measure the negative ion concentration in the air. The fiber sample is placed in a relatively closed and stable test environment to simulate the actual use scene, and the air flows around the sample, and then the air ion measurement instrument measures the number of negative ions in the air at a specific position and time point, so as to obtain the negative ion release amount of the fiber.

[0084] Detection principle: there is usually a collection device inside the instrument, which collects negative ions through an electric field and converts them into electrical signals for measurement and recording.

[0085] Washing resistance detection method:

[0086] Washing test combined with negative ion release detection. According to certain washing standards and procedures, the fiber sample is washed multiple times, such as using a household washing machine to simulate daily washing conditions, setting certain washing time, temperature, detergent concentration, etc. After washing, the negative ion release of the fiber is measured again, and the retention rate of washing resistance is obtained by calculating the ratio of negative ion release before and after washing.

[0087] Detection principle: By simulating the actual washing process, the change of negative ion release ability of the fiber during washing is investigated to evaluate the washing resistance of the fiber.

[0088] Breaking strength detection method:

[0089] Electronic universal material testing machine is used for detection. The fiber sample is made into a certain size sample, clamped on the fixture of the testing machine, and a constant speed is applied to the sample until the fiber breaks. The testing machine records the maximum tensile force at break, and calculates the breaking strength according to the original cross-sectional area of the sample.

[0090] Detection principle: Based on the principle of material mechanics, the resistance to breakage of the fiber is determined by measuring the stress in the tensile process.

[0091] Specific surface area detection method:

[0092] BET method is commonly used. This method uses gas adsorption principle, exposes the sample to adsorbed gas (such as nitrogen) at low temperature (usually liquid nitrogen temperature) under known pressure, so that gas molecules are physically adsorbed on the surface of the sample. By measuring the relationship between the amount of adsorbed gas and pressure, the specific surface area of the sample is calculated according to the BET theoretical model.

[0093] Detection principle: The larger the specific surface area of the material, the more gas molecules can be adsorbed. By measuring the amount of adsorbed gas, the specific surface area of the material can be indirectly calculated.

[0094] The detection results are as follows:

[0095]

[0096] Conclusion:

[0097] 1. Influence of core-shell structure on performance

[0098] Negative ion release:

[0099] Examples 1, 2 and 3 (core-shell structure) are significantly higher than Comparative Example 1 (without core-shell), indicating that the core-shell structure fixes tourmaline through chemical bonds, reduces the loss of ingredients, and improves the release efficiency.

[0100] Washing resistance:

[0101] The core-shell structure (Examples 1-3) has higher retention rate than Comparative Example 1 (60%), the shell layer protects the core component, reducing the detachment of tourmaline caused by washing friction.

[0102] Breaking strength:

[0103] Example 3 (shell layer 1 μm) has the highest strength (4.5 cN / dtex), thin shell layer reduces structural stress concentration, while the core layer accounts for a high proportion (70%) to enhance the overall toughness.

[0104] 2. Tourmaline content and carrier type

[0105] High tourmaline content (Example 2):

[0106] The highest amount of negative ions released (1500 ions / cm 3 ), but the washing resistance is slightly lower (78%), it is speculated that high filling leads to uneven dispersion of tourmaline, and local detachment during washing.

[0107] Carrier effect (Comparative Example 3):

[0108] The specific surface area of pure titanium dioxide is reduced to 180 m 2 / g, the amount of negative ions released (1050 ions / cm 3 ) is lower than that of the example (230 m 2 / g), which shows that the titanium dioxide / graphene composite carrier promotes the dispersion of tourmaline and the exposure of active sites through high specific surface area.

[0109] 3. Limitations of large particle size tourmaline

[0110] Comparative Example 2 (large particle size tourmaline) has a lower release amount (950 ions / cm 3 ) than the example, which may be due to high surface energy and serious agglomeration, and the active sites are shielded.

[0111] The washing resistance (65%) is poor, the interface between large particle size tourmaline and PET is weak, and it is easy to peel off during washing.

[0112] 4. Trade-off of shell thickness

[0113] Example 3 (shell layer 1 μm) has the optimal strength, but the release amount is slightly lower than Example 1, which shows that too thin shell layer may limit the loading efficiency of tourmaline.

[0114] Example 2 (shell layer 1.5 μm) has the highest release amount, but the strength decreases, and the shell thickness and mechanical properties need to be balanced.

[0115] 5. Key of modification and interface treatment

[0116] Silane-modified tourmaline (Examples 1-3) is more tightly bound to the PET interface, and the ester exchange reaction forms a chemical bond, significantly improving the structural stability (wash resistance retention rate 78-88%).

[0117] Comparative Example 3 did not use a graphene support, and the specific surface area decreased, resulting in a decrease in the release amount, verifying the enhancement of the composite support on the dispersion and activity of tourmaline.

[0118] The above is only a preferred embodiment of the present application, and does not limit the present application in any form. Although the present application has been disclosed as above with a preferred embodiment, it is not intended to limit the present application. Any person skilled in the art can make some changes or modifications to the above disclosed technical content to make equivalent embodiments with equivalent changes, without departing from the technical solution of the present application. Any simplification, modification, equivalent change and modification of the above embodiments made in accordance with the technical essence of the present application are still within the scope of the technical solution of the present application.

Claims

1. A negative ion polyester fiber, characterized by, Consists of the following raw materials by mass percentage: Polyethylene terephthalate: 85-92%, Nano tourmaline composite powder: 3-8%, Titanium dioxide / graphene composite carrier: 2-5%, Coupling agent: 0.5-1.5%, Antioxidant: 0.3-0.8%, The nano tourmaline composite powder is a composite of magnesium iron tourmaline and germanite with a particle size of 50-100 nm in a mass ratio of 3:

1.

2. The anion polyester fiber according to claim 1, wherein The polyester fiber adopts a core-shell structure, wherein: The core layer is a polyester master batch containing nano tourmaline composite powder, with a diameter of 60-70% of the diameter of the polyester fiber; The shell layer is a copolyester layer doped with a titanium dioxide / graphene composite carrier, with a thickness of 1-2 μm; The core-shell interface forms a chemical bond through ester exchange reaction.

3. A method of producing the negative ion polyester fiber as claimed in claim 2, characterized by, The method comprises the following steps: Step 1, master batch preparation: melt blend nano tourmaline composite powder, polyethylene terephthalate, and antioxidant at 280-300°C, and granulate by double screw extruder; Step 2, shell layer treatment: ultrasonically disperse titanium dioxide / graphene composite carrier and coupling agent in ethanol solution for 30 min, and graft to the copolyester segment by in-situ polymerization; Step 3, composite spinning: use a skin-core composite spinning machine, core layer feeding temperature 290-300°C, shell layer feeding temperature 275-285°C, spinning speed 2800-3200 m / min; Step 4, post-treatment: stretch the fiber in 3-5% aqueous citric acid solution, set the temperature to 110-130°C, and control the oiling rate to 0.6-1.2%.

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