Easily-dyed antioxidant nylon filament and preparation method thereof

Abstract

The invention provides an easy-to-dye antioxidant nylon filament and a preparation method thereof, and belongs to the technical field of nylon. The preparation method comprises the following steps: coupling porous silicon dioxide nanospheres coated and modified by polydopamine with an antioxidant of a silane coupling agent copolymerized with 3, 5-di-tert-butyl-4-hydroxystyrene acid, coating the surface with graphene oxide, adding into caprolactam, adding aminocaproic acid, heating, reducing pressure, stirring, reacting, discharging, cooling, drying and slicing to obtain nylon slices; and carrying out melt extrusion, spinning, cooling, oiling, drafting and shaping, and winding to obtain the easy-to-dye antioxidant nylon filament. The easy-to-dye antioxidant nylon 66 filament fiber has the advantages of good thermo-oxidative aging resistance, easy adsorption of pigment molecules, easy dyeing, high strength, good rigidity, impact resistance, oil resistance, chemical resistance, wear resistance, self-lubrication and the like, and especially has better hardness, rigidity, heat resistance and creep resistance.

Description

Technical Field

[0001] The invention relates to the technical field of nylon, and in particular to an easily dyeable and anti-oxidative nylon filament and a preparation method thereof. Background Art

[0002] Ultrafine fiber filament fabrics are now more and more widely used in people's lives, mainly used in high-end casual jackets, windbreakers, casual suits, trousers, casual cotton-padded clothes, and casual down jackets for men and women. Generally, it is mainly made of sea island ultrafine fiber filaments or polyester nylon ultrafine fiber filaments. The fabric is produced through processes such as pre-shrinking, alkali reduction and fiber opening, pre-setting, brushing and sanding, and dyeing to produce this kind of leather-feel velvet fabric. The molecular structure characteristics of nylon (containing amide groups, similar to protein structure) have good hydrophilicity and skin-friendliness, sweat absorption, light weight, good toughness, good resilience, acid and alkali resistance, etc. It is one of the most suitable artificial fabrics for human wear and is widely used in knitted underwear, socks, sportswear, ski jackets, tights and other fields. Application in clothing is also one of the main uses of nylon fiber. The micro-denier of nylon 6 fiber can further improve the quality and value of the fiber, and produce high-end clothing products that meet popular trends and fashion tastes. The single fiber fineness of nylon 6 fiber obtained by direct melt spinning can reach 0.80dtex.

[0003] However, the technology of directly producing differentiated micro-denier nylon 6POY fiber by conventional spinning modification is not mature yet. There are two reasons for this phenomenon: on the one hand, the production of differentiated micro-denier nylon by island spinning is complex and costly, and will also cause a large amount of organic matter emissions and environmental pollution, which obviously limits its promotion and application; on the other hand, due to the characteristics of nylon itself, the molecular structure contains a large number of hydrogen bonds, the crystallization speed is fast, the crystallinity is high, and it is not easy to stretch and deform.

[0004] Nylon materials are widely used in spinning, injection molding and film-making products due to their unique performance advantages, but nylon itself is easily oxidized and yellowed, which eventually leads to a reduction in its mechanical properties, becoming a major drawback. Adding a certain amount of antioxidants during the molding process is a simple and commonly used method, but due to the small amount added and the uneven dispersion of the antioxidants, the effect cannot be best reflected. Blending to prepare antioxidant masterbatches can alleviate the disadvantages of uneven dispersion of antioxidants to a certain extent, but blending to prepare antioxidant masterbatches itself will cause certain thermal degradation, which also has certain limitations for fields such as high-speed fiber production that require high stability of nylon raw materials. In addition, the specific surface area of ​​ultra-fine denier nylon fibers increases, the dyeing rate of dyes increases, the levelness becomes worse, and uneven dyeing is prone to occur.

[0005] Chinese patent CN1309899C is to dye the microfiber of the fabric after opening the chemical fiber and mechanical fiber. Since the suede fabric is made of polyester sea island fiber, polyester nylon microfiber and other fibers, the fiber fineness reaches about 0.2dtex after opening. The specific surface area of ​​the fiber is dozens of times that of conventional fibers, so the adsorption capacity of the fiber surface is greatly enhanced when dyeing with disperse dyes. Some dyes are combined with fibers for dyeing, and 1 / 4-1 / 3 of the dyes are adsorbed on the surface of the fibers, which often enter the sewage when the fabric is washed, increasing COD emissions and causing environmental pollution. Summary of the invention

[0006] The purpose of the present invention is to provide an easily dyeable and anti-oxidative nylon filament and a preparation method thereof, which has the advantages of good resistance to thermal oxidative aging, easy adsorption of colorant molecules, easy dyeing, high strength, good rigidity, impact resistance, oil resistance and chemical resistance, wear resistance and self-lubrication, especially better hardness, rigidity, heat resistance and creep performance.

[0007] The technical solution of the present invention is achieved in this way:

[0008] The invention provides a method for preparing an easily dyeable and anti-oxidation nylon filament. The method comprises the following steps: coupling a porous silica nanosphere coated with polydopamine and an antioxidant obtained by copolymerizing 3,5-di-tert-butyl-4-hydroxystyrene acid with a silane coupling agent, coating the surface with graphene oxide, adding the nanosphere into caprolactam, adding aminocaproic acid, heating, reducing pressure, stirring and reacting, discharging, cooling, drying and slicing to obtain nylon slices, and then melt extruding, spinning, cooling, oiling, drawing and shaping, and winding to obtain an easily dyeable and anti-oxidation nylon filament.

[0009] As a further improvement of the present invention, the following steps are included:

[0010] S1. dissolving an alkyl orthosilicate in an organic solvent to obtain a solution A; dissolving a porogen and an emulsifier in water to obtain a solution B; adding solution A dropwise to solution B, emulsifying, adjusting the pH value of the solution, stirring the reaction, centrifuging, washing, and drying to obtain porous silica nanospheres;

[0011] S2. adding porous silica nanospheres to water, adding dopamine hydrochloride and a catalyst, heating and stirring the reaction, centrifuging, washing, and drying to obtain modified porous silica nanospheres;

[0012] S3. Add 3,5-di-tert-butyl-4-hydroxyphenylethylene acid to ethanol, add a silane coupling agent with a double bond and an initiator, heat and stir to react, filter, wash, and dry to obtain an antioxidant;

[0013] S4. adding an antioxidant to water, adding NHS (N-Hydroxy succinimide) and EDC (1-(3-Dimethylaminopropyl)-3-ethylcarbodiimide), stirring to activate, adding modified porous silica nanospheres, stirring to react, centrifuging, washing, and drying to obtain a conjugate;

[0014] S5. Add the conjugate to the graphene oxide aqueous dispersion, disperse it evenly by ultrasonication, and spray dry it to obtain a wrinkled coating modifier;

[0015] S6. The caprolactam is heated to melt, aminocaproic acid and a wrinkle-type coating modifier are added, stirred and mixed evenly, heated and stirred under reduced pressure to react, discharged and cooled, dried, sliced, and nylon slices are obtained;

[0016] S7. The nylon slices are sent to the screw extruder, and the melt is conveyed to the spinning box by pressurization. After being metered by a metering pump, the filaments are sprayed through the spinning assembly. The filaments are cooled by side blowing to form a filament bundle. The cooled filament bundle is oiled to eliminate static electricity, and the oiled filament bundle is stretched and shaped. The shaped filament bundle is wound into a filament tube to obtain easy-to-dye and anti-oxidation nylon filaments.

[0017] As a further improvement of the present invention, the alkyl orthosilicate in step S1 is methyl orthosilicate or ethyl orthosilicate, the mass ratio of the alkyl orthosilicate, the porogen and the emulsifier is 12-15:1-2:0.5-1, the porogen is selected from at least one of hexadecyltrimethylammonium chloride, ethylene oxide-propylene oxide triblock copolymer PEO20-PPO70-PEO20 or ethylene oxide-propylene oxide triblock copolymer PEO106-PPO70-PEO106, the emulsifier is selected from at least one of Tween-20, Tween-40, Tween-60, Tween-80 or Tween-85, the pH value of the solution is adjusted to 9-10, and the stirring reaction time is 10-12h.

[0018] As a further improvement of the present invention, the mass ratio of the porous silica nanospheres, dopamine hydrochloride and catalyst in step S2 is 10-12:4-6:1-2, the catalyst is a Tris-HCl solution with a pH of 8.5-9.5, the temperature of the heating and stirring reaction is 45-55°C, and the time is 3-5h.

[0019] As a further improvement of the present invention, the mass ratio of 3,5-di-tert-butyl-4-hydroxyphenylvinyl alcohol, the silane coupling agent with a double bond and the initiator in step S3 is 4-7:3-5:0.01-0.02, the silane coupling agent with a double bond is selected from at least one of KH570, A151, and A171, the initiator is azobisisobutyronitrile, the temperature of the heating and stirring reaction is 50-60° C., and the time is 3-5 hours.

[0020] As a further improvement of the present invention, in step S4, the mass ratio of the antioxidant, NHS, EDC and modified porous silica nanospheres is 4-7:1-2:1-2:10, the stirring activation time is 20-30 minutes, and the stirring reaction time is 8-10 hours.

[0021] As a further improvement of the present invention, the concentration of the graphene oxide aqueous dispersion in step S5 is 0.5-1 mg / mL, and the liquid-to-solid ratio of the graphene oxide aqueous dispersion and the conjugate is 3-5 mL:1 g.

[0022] As a further improvement of the present invention, the temperature of the heating and melting in step S6 is 70-75°C, the mass ratio of the caprolactam, aminocaproic acid and the wrinkled coating modifier is 100:1-2:7-12, the temperature of the heating, reduced pressure and stirring reaction is 240-260°C, the rotation speed is 100-150r / min, the reaction pressure is 0.02-0.08MPa, and the time is 3-5h.

[0023] As a further improvement of the present invention, the temperature of the melt extrusion in step S7 is 280-300°C, the fineness of the filaments sprayed out by the spinneret is 0.05-0.1mm, and the amount of oil attached is controlled to be 0.5-1.5%; the stretching and shaping is achieved by 1 stage preheating, 2 stages stretching, and 2 stages shaping between six pairs of hot rollers: wherein the temperature of the first pair of hot rollers is 30-40°C, the temperature of the second pair of hot rollers is 45-55°C, the first pair of hot rollers and the second pair of hot rollers preheat the filaments, and the stretching ratio is 1-1.01 times; the winding speed is 3000-4000m / min.

[0024] The present invention further protects an easy-to-dye and anti-oxidation nylon filament prepared by the above preparation method.

[0025] The present invention has the following beneficial effects:

[0026] The invention copolymerizes 3,5-di-tert-butyl-4-hydroxyphenylphenolic acid and a silane coupling agent with a double bond to prepare an antioxidant. On the one hand, the antioxidant has a silane structure and can be well combined with silicon dioxide nanospheres. On the other hand, the macromolecular antioxidant containing polar groups, rigid five-membered rings and long-chain alkyl para-substituents in the molecular structure is prepared by a free radical polymerization method. The macromolecular antioxidant has a large relative molecular weight, good heat resistance and high thermal oxidation aging resistance efficiency, can significantly improve the thermal oxidation aging resistance of nylon, has good dispersibility, will not cause the decrease of the mechanical properties of nylon yarn, and the antioxidant itself is not easy to decompose. In addition, the antioxidant macromolecules are rich in carboxyl groups, which can be coupled with the amino groups on the modified porous silica nanospheres by activating the carboxyl groups to form a conjugate. The addition of the conjugate to nylon can significantly improve the mechanical strength of the nylon yarn. The porous silica nanospheres have a large specific surface area and are easy to adsorb colorant molecules. The polydopamine coated thereon can form complex bonds or hydrogen bonds with metal ions and colorant molecules, thereby having a good color fixation effect and being easy to dye.

[0027] Graphene oxide has good compatibility with nylon, but direct addition of it is easy to agglomerate and affect the mechanical properties of nylon. By coating graphene oxide on the surface of the conjugate and forming wrinkles through spray drying, the uniform dispersion of the nano-wrinkled coating modifier is achieved. Effective contact promotes the formation of a thermal conductive network, thereby improving its thermal conductivity, promoting the dispersion and compatibility of the wrinkled coating modifier in the nylon material, and it is not easy to agglomerate itself, which helps to improve the mechanical properties and heat dissipation properties of the material and reduce thermal shrinkage.

[0028] The easily dyeable and anti-oxidative nylon 66 filament fiber of the present invention has the advantages of good resistance to thermal oxidation aging, easy adsorption of colorant molecules, easy dyeing, high strength, good rigidity, impact resistance, oil resistance, chemical resistance, wear resistance and self-lubrication, especially better hardness, rigidity, heat resistance and creep performance. DETAILED DESCRIPTION

[0029] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] 0.5 mg / mL graphene oxide aqueous dispersion was purchased from Jiangsu Xianfeng Nanomaterial Technology Co., Ltd.

[0031] Example 1

[0032] This embodiment provides a method for preparing an easily dyeable and anti-oxidative nylon filament, comprising the following steps:

[0033] S1. 12 g of methyl orthosilicate was dissolved in 200 mL of dichloromethane to obtain solution A; 1 g of hexadecyltrimethylammonium chloride and 0.5 g of Tween-40 were dissolved in 300 mL of water to obtain solution B; solution A was added dropwise to solution B, emulsified at 7000 r / min for 15 min, the pH value of the solution was adjusted to 9, the reaction was stirred for 10 h, centrifuged, washed, and dried to obtain porous silica nanospheres;

[0034] S2. 10 g of porous silica nanospheres were added to 200 mL of water, 4 g of dopamine hydrochloride and 1 g of catalyst were added, heated to 45 ° C, stirred for 3 h, centrifuged, washed, and dried to obtain modified porous silica nanospheres;

[0035] The catalyst is a Tris-HCl solution with a pH of 8.5;

[0036] S3. 4 g of 3,5-di-tert-butyl-4-hydroxystyrene acid was added to 200 mL of ethanol, 3 g of silane coupling agent A151 and 0.01 g of azobisisobutyronitrile were added, heated to 50 ° C, stirred for 3 h, filtered, washed, and dried to obtain an antioxidant;

[0037] S4. Add 4 g of antioxidant to 200 mL of water, add 1 g of NHS and 1 g of EDC, stir and activate for 20 min, add 10 g of modified porous silica nanospheres, stir and react for 8 h, centrifuge, wash, and dry to obtain a conjugate;

[0038] S5. 10 g of the conjugate was added to 30 mL of 0.5 mg / mL graphene oxide aqueous dispersion, ultrasonically dispersed at 1000 W for 10 min, and spray dried to obtain a wrinkled coating modifier;

[0039] S6. 100g of caprolactam was heated to 75°C to melt, 1g of aminocaproic acid and 7g of wrinkle-type coating modifier were added, stirred and mixed for 15min, heated and stirred under reduced pressure to react at a temperature of 240°C, a speed of 100r / min, a reaction pressure of 0.02MPa, a time of 3h, discharged and cooled, dried, sliced, and nylon slices were obtained;

[0040] S7. The nylon slices are sent to a screw extruder and heated to 280°C to obtain a melt, the melt is conveyed to a spinning box by pressurization, and is metered by a metering pump and then spun through a spinning assembly, the fineness of the filaments sprayed out by the spinneret is 0.1 mm, the filaments are cooled by side blowing to form a filament bundle, the cooled filament bundle is oiled to eliminate static electricity, the amount of the oil is controlled to be 0.5%, and the oiled filament bundle is stretched and shaped, and the stretching and shaping is achieved by 1 stage preheating, 2 stages stretching, and 2 stages shaping between six pairs of hot rollers: wherein the temperature of the first pair of hot rollers is 30°C, and the temperature of the second pair of hot rollers is 45°C, the first pair of hot rollers and the second pair of hot rollers preheat the filaments, and the stretching ratio is 1 times; the filament bundle after the shaping treatment is wound into a filament tube, and the winding speed is 3000m / min to obtain easy-to-dye and anti-oxidation nylon filaments.

[0041] Example 2

[0042] This embodiment provides a method for preparing an easily dyeable and anti-oxidative nylon filament, comprising the following steps:

[0043] S1. 15 g of tetraethyl orthosilicate was dissolved in 200 mL of dichloromethane to obtain solution A; 2 g of ethylene oxide-propylene oxide triblock copolymer PEO106-PPO70-PEO106 and 1 g of Tween-60 were dissolved in 300 mL of water to obtain solution B; solution A was added dropwise to solution B, emulsified at 7000 r / min for 15 min, the pH value of the solution was adjusted to 10, the reaction was stirred for 12 h, centrifuged, washed, and dried to obtain porous silica nanospheres;

[0044] S2. 12 g of porous silica nanospheres were added to 200 mL of water, 6 g of dopamine hydrochloride and 2 g of catalyst were added, heated to 55 ° C, stirred for 5 h, centrifuged, washed, and dried to obtain modified porous silica nanospheres;

[0045] The catalyst is a Tris-HCl solution with a pH of 9.5;

[0046] S3. 7 g of 3,5-di-tert-butyl-4-hydroxystyrene acid was added to 200 mL of ethanol, 5 g of silane coupling agent A171 and 0.02 g of azobisisobutyronitrile were added, heated to 60 ° C, stirred for 5 h, filtered, washed, and dried to obtain an antioxidant;

[0047] S4. 7 g of antioxidant was added to 200 mL of water, 2 g of NHS and 2 g of EDC were added, and the mixture was stirred and activated for 30 min. 10 g of modified porous silica nanospheres were added, and the mixture was stirred and reacted for 10 h. The mixture was centrifuged, washed, and dried to obtain a conjugate.

[0048] S5. 10 g of the conjugate was added to 50 mL of 0.5 mg / mL graphene oxide aqueous dispersion, ultrasonically dispersed at 1000 W for 10 min, and spray dried to obtain a wrinkled coating modifier;

[0049] S6. 100g of caprolactam was heated to 75°C to melt, 2g of aminocaproic acid and 12g of pleated coating modifier were added, stirred and mixed for 15min, heated and stirred under reduced pressure to react at a temperature of 260°C, a speed of 150r / min, a reaction pressure of 0.08MPa, a time of 5h, discharged and cooled, dried, sliced, and nylon slices were obtained;

[0050] S7. The nylon slices are sent to a screw extruder, heated to 300°C to obtain a melt, and the melt is conveyed to a spinning box by pressurization, and then measured by a metering pump and then spun through a spinning assembly, wherein the fineness of the filaments sprayed out by the spinneret is 0.1 mm, and the filaments are cooled by side blowing to form a filament bundle, and the cooled filament bundle is oiled to eliminate static electricity, and the amount of the oil is controlled to be 1.5%, and the filament bundle after oiling is stretched and shaped, and the stretching and shaping is achieved by 1 stage preheating, 2 stages stretching, and 2 stages shaping between six pairs of hot rollers: wherein the temperature of the first pair of hot rollers is 40°C, and the temperature of the second pair of hot rollers is 55°C, and the first pair of hot rollers and the second pair of hot rollers preheat the filaments, and the stretching ratio is 1.01 times; the filament bundle after shaping is wound into a filament tube, and the winding speed is 4000m / min, to obtain easy-to-dye and anti-oxidation nylon filaments.

[0051] Example 3

[0052] This embodiment provides a method for preparing an easily dyeable and anti-oxidative nylon filament, comprising the following steps:

[0053] S1. 13 g of tetraethyl orthosilicate was dissolved in 200 mL of dichloromethane to obtain solution A; 1.5 g of ethylene oxide-propylene oxide triblock copolymer PEO20-PPO70-PEO20 and 0.8 g of Tween-85 were dissolved in 300 mL of water to obtain solution B; solution A was added dropwise to solution B, emulsified at 7000 r / min for 15 min, the pH value of the solution was adjusted to 9.5, the reaction was stirred for 11 h, centrifuged, washed, and dried to obtain porous silica nanospheres;

[0054] S2. 11 g of porous silica nanospheres were added to 200 mL of water, 5 g of dopamine hydrochloride and 1.5 g of catalyst were added, heated to 50 ° C, stirred for 4 h, centrifuged, washed, and dried to obtain modified porous silica nanospheres;

[0055] The catalyst is a Tris-HCl solution with a pH of 9;

[0056] S3. 5.5 g of 3,5-di-tert-butyl-4-hydroxystyrene acid was added to 200 mL of ethanol, 4 g of silane coupling agent KH570 and 0.015 g of azobisisobutyronitrile were added, heated to 55 ° C, stirred for 4 h, filtered, washed, and dried to obtain an antioxidant;

[0057] S4. 5 g of antioxidant was added to 200 mL of water, 1.5 g of NHS and 1.2 g of EDC were added, and the mixture was stirred and activated for 25 min. 10 g of modified porous silica nanospheres were added, and the mixture was stirred and reacted for 9 h. The mixture was centrifuged, washed, and dried to obtain a conjugate.

[0058] S5. 10 g of the conjugate was added to 40 mL of 0.5 mg / mL graphene oxide aqueous dispersion, ultrasonically dispersed at 1000 W for 10 min, and spray dried to obtain a wrinkled coating modifier;

[0059] S6. 100g of caprolactam was heated to 75°C to melt, 1.5g of aminocaproic acid and 10g of pleated coating modifier were added, stirred and mixed for 15min, heated and stirred under reduced pressure to react at a temperature of 250°C, a speed of 120r / min, a reaction pressure of 0.05MPa, a time of 4h, discharged and cooled, dried, sliced, and nylon slices were obtained;

[0060] S7. The nylon slices are sent to a screw extruder and heated to 290°C to obtain a melt, which is then conveyed to a spinning box by pressurization, and then metered by a metering pump and then spun through a spinning assembly, wherein the fineness of the filaments ejected by the spinneret is 0.1 mm, and the filaments are cooled by side blowing to form a filament bundle, and the cooled filament bundle is oiled to eliminate static electricity, and the amount of the oil is controlled to be 1%, and the filament bundle after oiling is subjected to a drawing and shaping treatment, and the drawing and shaping is achieved by 1 stage preheating, 2 stages stretching, and 2 stages shaping between six pairs of hot rollers: wherein the temperature of the first pair of hot rollers is 35°C, and the temperature of the second pair of hot rollers is 50°C, and the first pair of hot rollers and the second pair of hot rollers preheat the filaments, and the stretching ratio is 1 times; the filament bundle after shaping treatment is wound into a filament tube, and the winding speed is 3500m / min, to obtain easy-to-dye and anti-oxidation nylon filaments.

[0061] Comparative Example 1

[0062] Compared with Example 3, the difference is that the porogen ethylene oxide-propylene oxide triblock copolymer PEO20-PPO70-PEO20 is not added in step S1.

[0063] The details are as follows:

[0064] S1. Dissolve 13 g of tetraethyl orthosilicate in 200 mL of dichloromethane to obtain solution A; dissolve 2.3 g of Tween-85 in 300 mL of water to obtain solution B; add solution A dropwise into solution B, emulsify at 7000 r / min for 15 min, adjust the solution pH to 9.5, stir the reaction for 11 h, centrifuge, wash, and dry to obtain porous silica nanospheres.

[0065] Comparative Example 2

[0066] Compared with Example 3, the difference is that step S2 is not performed.

[0067] The details are as follows:

[0068] S1. 13 g of tetraethyl orthosilicate was dissolved in 200 mL of dichloromethane to obtain solution A; 1.5 g of ethylene oxide-propylene oxide triblock copolymer PEO20-PPO70-PEO20 and 0.8 g of Tween-85 were dissolved in 300 mL of water to obtain solution B; solution A was added dropwise to solution B, emulsified at 7000 r / min for 15 min, the pH value of the solution was adjusted to 9.5, the reaction was stirred for 11 h, centrifuged, washed, and dried to obtain porous silica nanospheres;

[0069] S2. Add 5.5 g of 3,5-di-tert-butyl-4-hydroxystyrene acid to 200 mL of ethanol, add 4 g of silane coupling agent KH570 and 0.015 g of azobisisobutyronitrile, heat to 55 ° C, stir to react for 4 h, filter, wash, and dry to obtain an antioxidant;

[0070] S3. 5 g of antioxidant was added to 200 mL of water, 1.5 g of NHS and 1.2 g of EDC were added, and the mixture was stirred and activated for 25 min. 10 g of porous silica nanospheres were added, and the mixture was stirred and reacted for 9 h. The mixture was centrifuged, washed, and dried to obtain a conjugate.

[0071] S4. 10 g of the conjugate was added to 40 mL of graphene oxide aqueous dispersion, ultrasonically dispersed at 1000 W for 10 min, and spray dried to obtain a wrinkled coating modifier;

[0072] S5. 100g of caprolactam was heated to 75°C to melt, 1.5g of aminocaproic acid and 10g of pleated coating modifier were added, stirred and mixed for 15min, heated and stirred under reduced pressure to react at a temperature of 250°C, a speed of 120r / min, a reaction pressure of 0.05MPa, a time of 4h, discharged and cooled, dried, sliced, and nylon slices were obtained;

[0073] S6. The nylon slices are sent to a screw extruder and heated to 290°C to obtain a melt, which is then conveyed to a spinning box by pressurization, and then metered by a metering pump and then spun through a spinning assembly, wherein the fineness of the filaments ejected by the spinneret is 0.1 mm, and the filaments are cooled by side blowing to form a filament bundle, and the cooled filament bundle is subjected to oiling to eliminate static electricity, and the amount of the oil is controlled to be 1%, and the filament bundle after oiling is subjected to a drawing and shaping treatment, and the drawing and shaping is achieved by 1 stage preheating, 2 stages stretching, and 2 stages shaping between six pairs of hot rollers: wherein the temperature of the first pair of hot rollers is 35°C, and the temperature of the second pair of hot rollers is 50°C, and the first pair of hot rollers and the second pair of hot rollers preheat the filaments, and the drawing ratio is 1 times; the filament bundle after shaping treatment is wound into a filament tube, and the winding speed is 3500m / min, to obtain easy-to-dye and anti-oxidation nylon filaments.

[0074] Comparative Example 3

[0075] Compared with Example 3, the difference is that step S3 is not performed, and the antioxidant in step S4 is 3,5-di-tert-butyl-4-hydroxyphenylacetic acid.

[0076] The details are as follows:

[0077] S1. 13 g of tetraethyl orthosilicate was dissolved in 200 mL of dichloromethane to obtain solution A; 1.5 g of ethylene oxide-propylene oxide triblock copolymer PEO20-PPO70-PEO20 and 0.8 g of Tween-85 were dissolved in 300 mL of water to obtain solution B; solution A was added dropwise to solution B, emulsified at 7000 r / min for 15 min, the pH value of the solution was adjusted to 9.5, the reaction was stirred for 11 h, centrifuged, washed, and dried to obtain porous silica nanospheres;

[0078] S2. 11 g of porous silica nanospheres were added to 200 mL of water, 5 g of dopamine hydrochloride and 1.5 g of catalyst were added, heated to 50 ° C, stirred for 4 h, centrifuged, washed, and dried to obtain modified porous silica nanospheres;

[0079] The catalyst is a Tris-HCl solution with a pH of 9;

[0080] S3. Add 5 g of 3,5-di-tert-butyl-4-hydroxyphenylacetic acid to 200 mL of water, add 1.5 g of NHS and 1.2 g of EDC, stir and activate for 25 min, add 10 g of modified porous silica nanospheres, stir and react for 9 h, centrifuge, wash, and dry to obtain a conjugate;

[0081] S4. 10 g of the conjugate was added to 40 mL of graphene oxide aqueous dispersion, ultrasonically dispersed at 1000 W for 10 min, and spray dried to obtain a wrinkled coating modifier;

[0082] S5. 100g of caprolactam was heated to 75°C to melt, 1.5g of aminocaproic acid and 10g of pleated coating modifier were added, stirred and mixed for 15min, heated and stirred under reduced pressure to react at a temperature of 250°C, a speed of 120r / min, a reaction pressure of 0.05MPa, a time of 4h, discharged and cooled, dried, sliced, and nylon slices were obtained;

[0083] S6. The nylon slices are sent to a screw extruder and heated to 290°C to obtain a melt, which is then conveyed to a spinning box by pressurization, and then metered by a metering pump and then spun through a spinning assembly, wherein the fineness of the filaments ejected by the spinneret is 0.1 mm, and the filaments are cooled by side blowing to form a filament bundle, and the cooled filament bundle is subjected to oiling to eliminate static electricity, and the amount of the oil is controlled to be 1%, and the filament bundle after oiling is subjected to a drawing and shaping treatment, and the drawing and shaping is achieved by 1 stage preheating, 2 stages stretching, and 2 stages shaping between six pairs of hot rollers: wherein the temperature of the first pair of hot rollers is 35°C, and the temperature of the second pair of hot rollers is 50°C, and the first pair of hot rollers and the second pair of hot rollers preheat the filaments, and the drawing ratio is 1 times; the filament bundle after shaping treatment is wound into a filament tube, and the winding speed is 3500m / min, to obtain easy-to-dye and anti-oxidation nylon filaments.

[0084] Comparative Example 4

[0085] Compared with Embodiment 3, the difference is that step S5 is not performed.

[0086] The details are as follows:

[0087] S1. 13 g of tetraethyl orthosilicate was dissolved in 200 mL of dichloromethane to obtain solution A; 1.5 g of ethylene oxide-propylene oxide triblock copolymer PEO20-PPO70-PEO20 and 0.8 g of Tween-85 were dissolved in 300 mL of water to obtain solution B; solution A was added dropwise to solution B, emulsified at 7000 r / min for 15 min, the pH value of the solution was adjusted to 9.5, the reaction was stirred for 11 h, centrifuged, washed, and dried to obtain porous silica nanospheres;

[0088] S2. 11 g of porous silica nanospheres were added to 200 mL of water, 5 g of dopamine hydrochloride and 1.5 g of catalyst were added, heated to 50 ° C, stirred for 4 h, centrifuged, washed, and dried to obtain modified porous silica nanospheres;

[0089] The catalyst is a Tris-HCl solution with a pH of 9;

[0090] S3. 5.5 g of 3,5-di-tert-butyl-4-hydroxystyrene acid was added to 200 mL of ethanol, 4 g of silane coupling agent KH570 and 0.015 g of azobisisobutyronitrile were added, heated to 55 ° C, stirred for 4 h, filtered, washed, and dried to obtain an antioxidant;

[0091] S4. 5 g of antioxidant was added to 200 mL of water, 1.5 g of NHS and 1.2 g of EDC were added, and the mixture was stirred and activated for 25 min. 10 g of modified porous silica nanospheres were added, and the mixture was stirred and reacted for 9 h. The mixture was centrifuged, washed, and dried to obtain a conjugate.

[0092] S5. 100 g of caprolactam was heated to 75 ° C to melt, 1.5 g of aminocaproic acid and 10 g of the conjugate were added, stirred and mixed for 15 min, heated and stirred under reduced pressure to react at a temperature of 250 ° C, a speed of 120 r / min, a reaction pressure of 0.05 MPa, a time of 4 h, discharged and cooled, dried, sliced, and nylon slices were obtained;

[0093] S6. The nylon slices are sent to a screw extruder and heated to 290°C to obtain a melt, which is then conveyed to a spinning box by pressurization, and then metered by a metering pump and then spun through a spinning assembly, wherein the fineness of the filaments ejected by the spinneret is 0.1 mm, and the filaments are cooled by side blowing to form a filament bundle, and the cooled filament bundle is oiled to eliminate static electricity, and the amount of the oil is controlled to be 1%, and the filament bundle after oiling is subjected to a drawing and shaping treatment, and the drawing and shaping is achieved by 1 stage preheating, 2 stages stretching, and 2 stages shaping between six pairs of hot rollers: wherein the temperature of the first pair of hot rollers is 35°C, and the temperature of the second pair of hot rollers is 50°C, and the first pair of hot rollers and the second pair of hot rollers preheat the filaments, and the stretching ratio is 1 times; the filament bundle after shaping treatment is wound into a filament tube, and the winding speed is 3500m / min, to obtain easy-to-dye and anti-oxidation nylon filaments.

[0094] Comparative Example 5

[0095] Compared with Example 3, the difference is that steps S3 and S4 are not performed, and the conjugate in step S5 is replaced by modified porous silica nanospheres.

[0096] The details are as follows:

[0097] S1. 13 g of tetraethyl orthosilicate was dissolved in 200 mL of dichloromethane to obtain solution A; 1.5 g of ethylene oxide-propylene oxide triblock copolymer PEO20-PPO70-PEO20 and 0.8 g of Tween-85 were dissolved in 300 mL of water to obtain solution B; solution A was added dropwise to solution B, emulsified at 7000 r / min for 15 min, the pH value of the solution was adjusted to 9.5, the reaction was stirred for 11 h, centrifuged, washed, and dried to obtain porous silica nanospheres;

[0098] S2. 11 g of porous silica nanospheres were added to 200 mL of water, 5 g of dopamine hydrochloride and 1.5 g of catalyst were added, heated to 50 ° C, stirred for 4 h, centrifuged, washed, and dried to obtain modified porous silica nanospheres;

[0099] The catalyst is a Tris-HCl solution with a pH of 9;

[0100] S3. 10 g of modified porous silica nanospheres were added to 40 mL of graphene oxide aqueous dispersion, ultrasonically dispersed at 1000 W for 10 min, and spray dried to obtain a wrinkled coated modifier;

[0101] S4. 100g of caprolactam was heated to 75°C to melt, 1.5g of aminocaproic acid and 10g of pleated coating modifier were added, stirred and mixed for 15min, heated and stirred under reduced pressure to react at a temperature of 250°C, a speed of 120r / min, a reaction pressure of 0.05MPa, a time of 4h, discharged and cooled, dried, sliced, and nylon slices were obtained;

[0102] S5. The nylon slices are sent to a screw extruder and heated to 290°C to obtain a melt, which is then conveyed to a spinning box by pressurization, and then metered by a metering pump and then spun through a spinning assembly, wherein the fineness of the filaments ejected by the spinneret is 0.1 mm, and the filaments are cooled by side blowing to form a filament bundle, and the cooled filament bundle is subjected to oiling to eliminate static electricity, and the amount of the oil is controlled to be 1%, and the filament bundle after oiling is subjected to a drawing and shaping treatment, and the drawing and shaping is achieved by 1 stage preheating, 2 stages stretching, and 2 stages shaping between six pairs of hot rollers: wherein the temperature of the first pair of hot rollers is 35°C, and the temperature of the second pair of hot rollers is 50°C, and the first pair of hot rollers and the second pair of hot rollers preheat the filaments, and the drawing ratio is 1 times; the filament bundle after shaping treatment is wound into a filament tube, and the winding speed is 3500m / min, to obtain easy-to-dye and anti-oxidation nylon filaments.

[0103] Test Example 1 Yellow Index Test

[0104] The easy-to-dye anti-oxidation nylon filaments prepared in Examples 1-3 or Comparative Examples 1-5 were placed in a ventilation heat aging test box, the temperature of the aging box was set to 180°C, the opening of the ventilation valve was 1 / 2, and the ventilation was performed by blowing. After an interval of 120 minutes, the sample to be tested was taken out, and its yellow index (YI value) was measured using a CM-3600d spectrophotometer according to HG / 3862-2006.

[0105] The results are shown in Table 1.

[0106] Table 1

[0107] Group Yellowness Index (YI value) Example 1 12.1 Example 2 11.9 Example 3 11.4 Comparative Example 1 12.4 Comparative Example 2 27.5 Comparative Example 3 23.9 Comparative Example 4 14.5 Comparative Example 5 34.8

[0108] It can be seen from the above table that the yellow value of the easily dyeable and antioxidant nylon filaments prepared in Examples 1-3 of the present invention is very low, and has a good effect of resisting discoloration.

[0109] Test Example 2

[0110] The easy-to-dye anti-oxidation nylon filaments prepared in Examples 1-3 or Comparative Examples 1-5 were placed in a ventilation heat aging test box, the temperature of the aging box was set to 180°C, the opening of the ventilation valve was 1 / 2, and the ventilation was performed by blowing. The samples to be tested were taken out after an interval of 120 minutes, and the breaking strength and breaking elongation of the samples to be tested were tested before and after the thermal oxidation aging test.

[0111] The results are shown in Table 2.

[0112] Table 2

[0113]

[0114] It can be seen from the above table that the easy-to-dye anti-oxidation nylon filaments prepared in Examples 1-3 of the present invention have good mechanical properties and good anti-oxidation properties.

[0115] Test Example 3

[0116] The easy-to-dye and anti-oxidation nylon filaments prepared in Examples 1-3 or Comparative Examples 1-5 were subjected to performance tests.

[0117] The results are shown in Table 3.

[0118] Table 3

[0119] Group Thermal shrinkage (%) Linear density coefficient of variation (%) Example 1 1.7 0.44 Example 2 1.8 0.45 Example 3 1.5 0.42 Comparative Example 1 2.0 0.48 Comparative Example 2 2.7 0.54 Comparative Example 3 3.3 0.87 Comparative Example 4 5.9 1.95 Comparative Example 5 7.8 2.89

[0120] It can be seen from the above table that the easy-to-dye and anti-oxidation nylon filaments prepared in Examples 1-3 of the present invention have good comprehensive properties.

[0121] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for preparing easily dyeable and anti-oxidative nylon filaments, characterized in that: The porous silica nanospheres modified by coating with polydopamine are coupled with an antioxidant prepared by copolymerizing 3,5-di-tert-butyl-4-hydroxyphenylethylene acid with a silane coupling agent, and the surface is coated with graphene oxide, added to caprolactam, and then aminocaproic acid is added. The reaction is heated, reduced in pressure, stirred, and cooled, dried, and sliced ​​to obtain nylon slices. After melt extrusion, spinning, cooling, oiling, drawing and shaping, and winding, easy-to-dye antioxidant nylon filaments are obtained.

2. The preparation method according to claim 1, characterized in that: The following steps are involved: S1. dissolving an alkyl orthosilicate in an organic solvent to obtain a solution A; dissolving a porogen and an emulsifier in water to obtain a solution B; adding solution A dropwise to solution B, emulsifying, adjusting the pH value of the solution, stirring the reaction, centrifuging, washing, and drying to obtain porous silica nanospheres; S2. adding porous silica nanospheres to water, adding dopamine hydrochloride and a catalyst, heating and stirring the reaction, centrifuging, washing, and drying to obtain modified porous silica nanospheres; S3. Add 3,5-di-tert-butyl-4-hydroxyphenylethylene acid to ethanol, add a silane coupling agent with a double bond and an initiator, heat and stir to react, filter, wash, and dry to obtain an antioxidant; S4. adding an antioxidant to water, adding NHS and EDC, stirring to activate, adding modified porous silica nanospheres, stirring to react, centrifuging, washing, and drying to obtain a conjugate; S5. Add the conjugate to the graphene oxide aqueous dispersion, disperse it evenly by ultrasonication, and spray dry it to obtain a wrinkled coating modifier; S6. The caprolactam is heated to melt, aminocaproic acid and a wrinkle-type coating modifier are added, stirred and mixed evenly, heated and stirred under reduced pressure to react, discharged and cooled, dried, sliced, and nylon slices are obtained; S7. The nylon slices are sent to the screw extruder, and the melt is conveyed to the spinning box by pressurization. After being metered by a metering pump, the filaments are sprayed through the spinning assembly. The filaments are cooled by side blowing to form a filament bundle. The cooled filament bundle is oiled to eliminate static electricity, and the oiled filament bundle is stretched and shaped. The shaped filament bundle is wound into a filament tube to obtain easy-to-dye and anti-oxidation nylon filaments.

3. The preparation method according to claim 2, characterized in that: The alkyl orthosilicate in step S1 is methyl orthosilicate or ethyl orthosilicate, the mass ratio of the alkyl orthosilicate, the porogen and the emulsifier is 12-15:1-2:0.5-1, the porogen is selected from at least one of hexadecyltrimethylammonium chloride, ethylene oxide-propylene oxide triblock copolymer PEO20-PPO70-PEO20 or ethylene oxide-propylene oxide triblock copolymer PEO106-PPO70-PEO106, the emulsifier is selected from at least one of Tween-20, Tween-40, Tween-60, Tween-80 or Tween-85, the pH value of the solution is adjusted to 9-10, and the stirring reaction time is 10-12h.

4. The preparation method according to claim 2, characterized in that: The mass ratio of the porous silica nanospheres, dopamine hydrochloride and catalyst in step S2 is 10-12:4-6:1-2, the catalyst is a Tris-HCl solution with a pH of 8.5-9.5, the temperature of the heating and stirring reaction is 45-55° C., and the time is 3-5 hours.

5. The preparation method according to claim 2, characterized in that: The mass ratio of 3,5-di-tert-butyl-4-hydroxyphenylvinyl alcohol, the silane coupling agent with a double bond and the initiator in step S3 is 4-7:3-5:0.01-0.02, the silane coupling agent with a double bond is selected from at least one of KH570, A151 and A171, the initiator is azobisisobutyronitrile, the temperature of the heating and stirring reaction is 50-60° C., and the time is 3-5 hours.

6. The preparation method according to claim 2, characterized in that: In step S4, the mass ratio of the antioxidant, NHS, EDC and modified porous silica nanospheres is 4-7:1-2:1-2:10, the stirring activation time is 20-30 minutes, and the stirring reaction time is 8-10 hours.

7. The preparation method according to claim 2, characterized in that: The concentration of the graphene oxide aqueous dispersion in step S5 is 0.5-1 mg / mL, and the liquid-to-solid ratio of the graphene oxide aqueous dispersion and the conjugate is 3-5 mL:1 g.

8. The preparation method according to claim 2, characterized in that: The heating and melting temperature in step S6 is 70-75°C, the mass ratio of caprolactam, aminocaproic acid and wrinkle-type coating modifier is 100:1-2:7-12, the heating and reduced pressure stirring reaction temperature is 240-260°C, the rotation speed is 100-150r / min, the reaction pressure is 0.02-0.08MPa, and the time is 3-5h.

9. The preparation method according to claim 2, characterized in that: The temperature of the melt extrusion in step S7 is 280-300°C, the fineness of the filaments sprayed out by the spinneret is 0.05-0.1mm, and the amount of oil attached is controlled to be 0.5-1.5%; the stretching and shaping is achieved by 1-stage preheating, 2-stage stretching, and 2-stage shaping between six pairs of hot rollers: wherein the temperature of the first pair of hot rollers is 30-40°C, the temperature of the second pair of hot rollers is 45-55°C, the first pair of hot rollers and the second pair of hot rollers preheat the filaments, and the stretching ratio is 1-1.01 times; the winding speed is 3000-4000m / min.

10. An easily dyeable and anti-oxidative nylon filament prepared by the preparation method according to any one of claims 1 to 9.

Images