A preparation method of anti-static flame-retardant polyester mother yarn

Abstract

The present invention relates to the field of preparation of anti-static flame-retardant polyester, and discloses a method for preparing anti-static flame-retardant polyester mother yarn, comprising the following steps: spinning the anti-static flame-retardant polyester melt after melt conveying, at a spinning temperature of 276-278°C, through a multi-hole spinneret to obtain a tow; the tow is first cooled by side-blowing air and oiled by a tanker, and then stretched by two rollers, with the temperature of the first hot roller being 110-115°C, the draw ratio being 3.3-3.6, the speed being 1200-1300 m / min, and the temperature of the second hot roller being 120-125°C; and finally, winding to obtain the anti-static flame-retardant polyester mother yarn. The present invention improves and optimizes various process parameters during the polyester melt spinning process, so that the whiskers in the polyester melt and the flame retardant produce a synergistic effect, thereby improving the flame retardant and anti-melt dripping effect of the melt, thereby obtaining a polyester mother yarn with stable flame retardant properties, environmental protection, and excellent post-processing properties.

Description

Technical Field

[0001] The invention relates to the field of preparation of anti-static and flame-retardant polyester, in particular to a preparation method of anti-static and flame-retardant polyester mother yarn. Background Art

[0002] With the continuous advancement of spinning technology, some polyester varieties can now be produced using multi-hole spinnerets. This first produces a mother fiber, which is then separated into monofilaments. The resulting polyester filaments have a monofilament fineness of 10-30D, which can be widely used in consumer yarns such as wedding dresses, evening gowns, warp knitted fabrics, sneaker linings, and industrial printing screens and ribbons. The traditional UDY-DT process for producing polyester monofilaments has a spinning speed of 700-900 m / min, resulting in uneven dyeing and poor overall performance. This has led to a tight supply situation in the domestic polyester monofilament market, which relies heavily on imports.

[0003] In the past decade, some domestic companies have also adopted the FDY spinning process to produce mother yarn. For example, the three-roller stretching FDY process is used to produce polyester mother yarn, or the conventional chip spinning FDY process is used to produce polyester mother yarn. The spinning speed can reach more than 4000m / min, which greatly improves production efficiency. However, the long process and high energy consumption of these two processes limit their widespread application. The Chinese invention patent with publication number CN106087099B discloses a method for preparing polyester FDY mother yarn and its monofilament. The antibacterial polyester melt containing cuprous material is added to a conventional polyester melt pipeline by melt direct spinning pipeline addition, mixed by a static mixer in the melt pipeline, and then subjected to melt spinning, cooling, drawing and heat setting, and winding processes to obtain polyester fiber mother yarn. The spinning box temperature of antibacterial polyester mother yarn is 292℃, the side blowing wind speed is 0.7-0.8m / s, the wind temperature is 16-18℃, the first hot roller temperature is 95℃, the second hot roller temperature is 150℃, and the winding speed is 3900-4500m / min. However, the melt dispersion of this blended spinning process is uneven, resulting in poor product quality and low quality of superior products. The Chinese invention patent with publication number CN102978735B discloses a method for manufacturing flame-retardant and anti-melting drip polyester. Although it can produce highly flame-retardant and anti-melting drip polyester, it adopts a composite spinning method with a skin-core structure. The fluidity of the polyester melt is not suitable for mother yarn production, which can easily cause spinning difficulties in mother yarn production. Summary of the Invention

[0004] In order to solve the technical problems of spinning difficulties and poor product quality in the production process of flame-retardant polyester master yarn, the present invention provides a preparation method of anti-static flame-retardant polyester master yarn. By improving the spinning temperature of the polyester melt and the double-roller stretching conditions, the fluidity and stretchability of the melt are adjusted to a better state, thereby optimizing the spinning effect, and obtaining a polyester master yarn with stable flame retardant performance, environmental protection, and good post-processing performance.

[0005] The purpose of the present invention is achieved through the following technical scheme: The present invention provides a preparation method of anti-static and flame-retardant polyester mother yarn, comprising the following steps: the anti-static and flame-retardant polyester melt is melt-conveyed and then spun, the spinning temperature is 276-278°C, and the yarn bundle is obtained by spinning through a porous spinneret; the yarn bundle is first cooled by side blowing and oiled by an oil tanker, and then stretched by two rollers, the temperature of the first hot roller is 110-115°C, the stretching ratio is 3.3-3.6, the speed is 1200-1300m / min, and the temperature of the second hot roller is 120-125°C; finally, the anti-static and flame-retardant polyester mother yarn is obtained by winding.

[0006] In the prior art, the production of FDY polyester master yarn presents the following major technical difficulties: spinning difficulties, cooling uniformity, stretching uniformity, winding and lubrication issues. Among these, the spinning temperature of the polyester melt and the double-roll stretching conditions are particularly important for the spinning effect. The present invention uses a lower spinning temperature than the prior art, which allows for better melt fluidity and spinning results. The yarn is then passed through a multi-porous spinneret to produce a tow. The tow is first cooled by side-blown air and lubricated by a tanker before being stretched by two rollers. The temperature and stretching rate between the first and second heated rollers are carefully coordinated to further improve the dispersion of whiskers and flame retardants in the melt, enhance the uniformity of the polyester master yarn, and improve its overall performance. Finally, after winding and lubrication, the anti-static and flame-retardant polyester master yarn is obtained. The entire production process is short, the transformation cost is low, the master yarn has stable flame-retardant properties, is environmentally friendly, and has excellent post-processing properties. Furthermore, the master yarn can be flexibly switched between conventional varieties, allowing companies to quickly start production and achieve profitability.

[0007] Preferably, the micropore diameter of the porous spinneret is 0.5-0.7 mm and the depth is 1-2 mm; the wind speed of the side blowing is 0.7-0.85 m / s, the wind temperature is 16-18°C, and the cooling height of the filament bundle is 2-3 m; the diameter of the oil tanker is 250-500 mm; the filament bundle is wound on the first hot roller for 10-12 turns, and the filament bundle is wound on the second hot roller for 8-10 turns; the winding speed is 3900-4100 m / min, and the winding tension is 40-60 cN.

[0008] The micropores on the porous spinneret are arranged in concentric circles. The shear rate of the polyester melt passing through the spinneret is within the ideal shear rate range. The relaxation time of the melt in the spinneret is greater than the relaxation time of high-speed spinning PET, and the melt has good spinnability.

[0009] During the cross-blowing process, the wind window height is adjustable from 0.5 to 1.5 meters at the lower edge, allowing for flexible product switching. The cross-blowing process conditions affect the uniformity of the mother yarn cooling. If the wind speed is too low, the wind temperature is too high, or the cooling height is too low, the mother yarn will not cool sufficiently, making it difficult to separate the yarns during post-processing or prone to doubling during production. Conversely, if the wind speed is too high, the wind temperature is too low, or the cooling height is too high, the mother yarn will cool too quickly, and a skin-core structure may occur during production, resulting in broken ends.

[0010] This oil tanker diameter can increase the contact area between the yarn and the oil tanker, improving the uniformity of oiling. In addition, at this winding speed and tension, the mother yarn is evenly heated and the spinning winding tension is stable.

[0011] Preferably, the method for preparing the anti-static flame-retardant polyester melt comprises the following steps:

[0012] (1) mixing basic magnesium sulfate whiskers and tetrapod-shaped zinc oxide whiskers, calcining the mixture in vacuum, dispersing the mixture in anhydrous ethanol containing sodium hexametaphosphate, and subjecting the mixture to atmospheric pressure plasma treatment; filtering the mixture, dispersing the resulting precipitate in water containing calcium stearate, ultrasonicating the mixture, filtering the mixture, and drying the mixture to obtain modified antistatic whiskers;

[0013] (2) mixing the modified antistatic whisker, the intumescent flame retardant, the microencapsulated red phosphorus flame retardant, the silane coupling agent and the nonionic surfactant to obtain a mixture, and then adding the mixture and sodium hexametaphosphate into ethylene glycol for ultrasonic dispersion to obtain an antistatic flame retardant whisker dispersion;

[0014] (3) The antistatic flame retardant whisker dispersion and ethylene terephthalate are mixed, and subjected to esterification and polycondensation to obtain an antistatic flame retardant polyester melt.

[0015] Basic magnesium sulfate whiskers are a new type of inorganic flame-retardant, reinforcing, non-toxic and environmentally friendly needle-shaped fiber material with a single crystal structure. When used as a flame retardant, they can suppress smoke and prevent dripping. Tetrapod-shaped zinc oxide whiskers have a unique three-dimensional four-needle structure and have antistatic and antibacterial functions. The two whiskers are dispersed in the melt to form a grid structure. The intumescent flame retardant and microencapsulated red phosphorus flame retardant are dispersed in the grid and polymerize in situ with PTA and ethylene glycol. That is, the whiskers and the flame retardants produce a synergistic effect, making the flame retardant and anti-drip effects of the melt even better. Moreover, the use of sodium hexametaphosphate and calcium stearate to modify the antistatic whiskers can improve the dispersibility of the whiskers and enhance the spinning uniformity of the polyester melt. The antistatic flame-retardant polyester melt obtained in the present invention has good fluidity and is more suitable for polyester mother yarn production. In addition, the improvement and coordination of various process parameters in the spinning process can produce polyester mother yarn with better spinning effect.

[0016] Preferably, in step (1), the mass ratio of the basic magnesium sulfate whiskers to the four-needle zinc oxide whiskers is 4-8:2-6; the average diameter of the basic magnesium sulfate whiskers is 0.1-1 μm, and the average length is 5-12 μm; the average diameter of the four-needle zinc oxide whiskers is 0.1-0.8 μm, and the average length is 6-10 μm.

[0017] Preferably, in step (1), the vacuum roasting is carried out at 350-450° C. for 4-6 hours; the concentration of the anhydrous ethanol containing sodium hexametaphosphate is 0.02-0.05%; and the concentration of the water containing calcium stearate is 0.2-0.3%.

[0018] Preferably, in step (2), the modified antistatic whiskers are further subjected to a post-treatment process before mixing, specifically comprising the following steps: dispersing the modified antistatic whiskers in water containing 2-amino-5-guanidine-valeric acid, and performing normal pressure plasma treatment, and then filtering to obtain a filtrate; adding the filtrate, vanillin, and sodium bicarbonate to a mixed solvent of methanol and water, heating to reflux reaction for 3 to 4 hours, then adding sodium borohydride and stirring at 30 to 40° C. for 8 to 10 hours, then filtering, washing, and vacuum drying to obtain a precipitate; adding the precipitate, triethanolamine oleate, and benzoyl peroxide to toluene, reacting at 80 to 90° C. for 5 to 8 hours, then distilling under reduced pressure, adding to anhydrous ether to cool and precipitate, and then vacuum drying to obtain the post-treated modified antistatic whiskers.

[0019] The modified antistatic whiskers undergo lubrication modification with calcium stearate, and post-treatment further forms a localized lubricating interface, improving compatibility with the polyester matrix and melt flowability. 2-amino-5-guanidine-pentanoic acid and calcium stearate form ionic bonds, loading the whisker surface. Vanillin is then grafted onto the surface functional groups. The aldehyde groups in the vanillin undergo reductive amination with the 2-amino-5-guanidine-pentanoic acid, leaving the remaining groups to be further grafted with the long carbon chain of triethanolamine oleate. This structure, rich in amino, guanidine, and hydroxyl groups, promotes binding and dispersibility with the flame retardant, resulting in a better synergistic effect. The addition of long carbon-chain alkyl groups also acts as an internal lubricant between the flame retardant and the polyester matrix, optimizing the localized lubricating interface, improving the dispersion of the whiskers and lubricant, and enhancing melt flowability. Furthermore, the introduction of vanillin can improve dyeing quality and uniformity to a certain extent, resulting in a polyester mother yarn with better spinning performance.

[0020] Preferably, the mass volume ratio of the modified antistatic whisker and the water containing 2-amino-5-guanidine-valeric acid is 0.1 g:6-10 mL; the concentration of the water containing 2-amino-5-guanidine-valeric acid is 0.08-0.12 g / mL; the mass volume ratio of the filtrate, vanillin, sodium bicarbonate, sodium borohydride and mixed solvent is 1 g:3-6 g:0.2-0.5 g:0.05-0.1 g:50 mL; the volume ratio of methanol and water in the mixed solvent is 10:1-2; the mass volume ratio of the precipitate, triethanolamine oleate, benzoyl peroxide and toluene is 1 g:4-9 g:0.2-0.4 g:50 mL.

[0021] The ratio of the added amount of each raw material in the post-treatment process will affect the molecular chain structure of the graft. If it exceeds this range, it will lead to excessive grafting, which is not conducive to melt fluidity and spinning effect.

[0022] Preferably, in step (2), the mass ratio of the modified antistatic whisker, intumescent flame retardant, microencapsulated red phosphorus flame retardant, silane coupling agent and non-ionic surfactant is 6-10:4-8:1-2:0.5-1.5:0.1-0.3; the mixing is carried out by stirring and mixing at 70-80°C for 45-60 minutes; the mass ratio of the mixture, sodium hexametaphosphate and ethylene glycol is 4-6:0.1-0.3:4-6; and the ultrasonic dispersion is carried out by ultrasonic dispersion at 50-60°C for 2.5-5 hours.

[0023] Preferably, in step (3), the mass ratio of the antistatic flame retardant whisker dispersion to ethylene terephthalate is 30-40:60-70.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] (1) By improving and optimizing the various process parameters in the polyester melt spinning process, the spinning difficulties, cooling uniformity, stretching uniformity, winding molding and oiling problems in the existing production process are overcome, and a polyester mother yarn with stable flame retardant properties, environmental protection and good post-processing performance is obtained;

[0026] (2) The whiskers and flame retardants in the polyester melt produce a synergistic effect, which makes the flame retardant and anti-melting effect of the melt better, and controls the proportion of each component to improve the melt fluidity;

[0027] (3) The entire production process is short, the transformation cost is low, and the mother wire and conventional varieties can be flexibly switched, allowing enterprises to quickly start production and make profits. DETAILED DESCRIPTION

[0028] The technical solutions of the present invention are described below with specific embodiments, but the protection scope of the present invention is not limited thereto:

[0029] Overall embodiment

[0030] A method for preparing an anti-static and flame-retardant polyester mother yarn comprises the following steps:

[0031] (1) mixing basic magnesium sulfate whiskers with an average diameter of 0.1 to 1 μm and an average length of 5 to 12 μm and tetrapod-shaped zinc oxide whiskers with an average diameter of 0.1 to 0.8 μm and an average length of 6 to 10 μm in a mass ratio of 4 to 8:2 to 6, calcining them at 350 to 450° C. in vacuum for 4 to 6 hours, and then dispersing them in anhydrous ethanol containing sodium hexametaphosphate at a concentration of 0.02 to 0.05%, and performing normal pressure plasma treatment; then filtering, dispersing the obtained precipitate in water containing calcium stearate at a concentration of 0.2 to 0.3%, and ultrasonicating, and then filtering and drying to obtain modified antistatic whiskers;

[0032] (2) The modified antistatic whiskers can also undergo a post-treatment process: the modified antistatic whiskers are dispersed in 0.08-0.12 g / mL of water containing 2-amino-5-guanidine-valeric acid, wherein the mass volume ratio of the modified antistatic whiskers to the water containing 2-amino-5-guanidine-valeric acid is 0.1 g:6-10 mL, and a normal pressure plasma treatment is performed, followed by filtration to obtain a filtrate; the filtrate, vanillin, and sodium bicarbonate are added to methanol and water in a volume ratio of 10:1-10. 2, heated to reflux reaction for 3 to 4 hours, then added with sodium borohydride and stirred at 30 to 40 ° C for 8 to 10 hours, the mass volume ratio of the filtrate, vanillin, sodium bicarbonate, sodium borohydride and mixed solvent is 1g: 3 to 6g: 0.2 to 0.5g: 0.05 to 0.1g: 50mL, and then filtered, washed and vacuum dried to obtain a precipitate; the precipitate, triethanolamine oleate and benzoyl peroxide are added to toluene, the The mass volume ratio of the precipitate, triethanolamine oleate, benzoyl peroxide and toluene is 1g:4-9g:0.2-0.4g:50mL, the reaction is carried out at 80-90°C for 5-8h, and then the mixture is distilled under reduced pressure, added to anhydrous ether and cooled to precipitate, and then vacuum dried to obtain a post-treated modified antistatic whisker; the modified antistatic whisker (or the post-treated modified whisker) with a mass ratio of 6-10:4-8:1-2:0.5-1.5:0.1-0.3 is prepared. The mixture is stirred at 70-80°C for 45-60 minutes to obtain a mixture, and the mixture and sodium hexametaphosphate are added to ethylene glycol and ultrasonically dispersed at 50-60°C for 2.5-5 hours. The mass ratio of the mixture, sodium hexametaphosphate and ethylene glycol is 4-6:0.1-0.3:4-6 to obtain an antistatic flame retardant whisker dispersion.

[0033] (3) The antistatic flame retardant whisker dispersion and ethylene terephthalate in a mass ratio of 30-40:60-70 are mixed, and the mixture is esterified and polycondensed to obtain an antistatic flame retardant polyester melt.

[0034] (4) The anti-static flame-retardant polyester melt is spun after melt conveying, the spinning temperature is 276-278°C, and the filament bundle is spun through a porous spinneret (micropore diameter is 0.5-0.7mm, depth is 1-2mm); the filament bundle is first cooled by side blowing, the wind speed of the side blowing is 0.7-0.85m / s, the wind temperature is 16-18°C, and the filament bundle cooling height is 2-3m; then it is oiled by an oil tanker (diameter is 250-500mm), and then two rollers are used for the spinning process. Stretching, the temperature of the first hot roller is 110-115°C, the filament bundle is wound on the first hot roller for 10-12 turns, the stretching ratio is 3.3-3.6, the speed is 1200-1300 m / min, the temperature of the second hot roller is 120-125°C, and the filament bundle is wound on the second hot roller for 8-10 turns; finally, after winding, the winding speed is 3900-4100 m / min, and the winding tension is 40-60 cN to obtain anti-static flame-retardant polyester mother yarn.

[0035] Example 1

[0036] A method for preparing an anti-static and flame-retardant polyester mother yarn comprises the following steps:

[0037] (1) After mixing, by weight, 7 parts of basic magnesium sulfate whiskers with an average diameter of 0.6 μm and an average length of 10 μm and 5 parts of tetrapod-shaped zinc oxide whiskers with an average diameter of 0.5 μm and an average length of 8 μm, the mixture was vacuum-baked at 420° C. for 5 h, and after cooling, the mixture was dispersed in anhydrous ethanol containing sodium hexametaphosphate at a concentration of 0.03%, stirred and sheared for 40 min, and subjected to normal pressure plasma treatment for 20 min; the mixture was then filtered, and the resulting precipitate was dispersed in water containing calcium stearate at a concentration of 0.2% and ultrasonicated at 60° C. for 35 min, and the suspended whiskers on the upper layer of the solution were filtered through 200 mesh, and the operation was repeated 4 times until the filtration was clear, and all the suspended whiskers obtained by filtration were dried to obtain modified antistatic whiskers;

[0038] (2) 8 parts by mass of modified antistatic whiskers, 5 parts by mass of intumescent flame retardant (melamine urate), 1 part by mass of microencapsulated red phosphorus flame retardant, 1 part by mass of silane coupling agent (KH-550) and 0.3 parts by mass of nonionic surfactant (pentaerythritol stearate) were mixed and stirred at 75°C for 60 minutes to obtain a mixture. 5 parts by mass of the mixture and 0.3 parts by mass of sodium hexametaphosphate were added to 5 parts by mass of ethylene glycol and ultrasonically dispersed at 55°C for 4 hours to obtain an antistatic flame retardant whisker dispersion.

[0039] (3) According to the parts by mass, 35 parts of antistatic flame retardant whisker dispersion and 70 parts of ethylene terephthalate are mixed in an esterification kettle, and first undergo an esterification reaction: an esterification temperature of 250°C, a pressure of 70KPa, and an esterification degree of 90%; a second esterification temperature of 253°C, a pressure of 25KPa, and an esterification degree of 96%; and then undergo a polycondensation reaction: a pre-shrinkage temperature of 260-265°C, a pressure of 11KPa, and an acid value of 1000 mol / ton; a second pre-shrinkage temperature of 269-270°C, a pressure of 1.5KPa, and an acid value of 470 mol / ton; a third final polycondensation temperature of 275-277°C, a pressure of 240Pa, and an acid value of 30 mol / ton, to obtain an antistatic flame retardant polyester melt.

[0040] (4) The anti-static flame-retardant polyester melt is spun after melt conveying, and the spinning temperature is 276-278°C. The yarn is spun through a porous spinneret (micropore diameter is 0.5 mm, and depth is 1.5 mm) to obtain a yarn bundle; the yarn bundle is first cooled by side blowing, the wind speed of the side blowing is 0.8 m / s, the wind temperature is 17°C, and the yarn bundle cooling height is 2.5 m; then it is oiled by an oil tanker (diameter is 400 mm), and then stretched by two rollers, the temperature of the first hot roller is 112-115°C, the yarn bundle is wound on the first hot roller for 12 turns, the stretching ratio is 3.4, the speed is 1250 m / min, the temperature of the second hot roller is 122-125°C, the yarn bundle is wound on the second hot roller for 9 turns; finally, it is wound, the winding speed is 4000 m / min, and the winding tension is 55 cN to obtain the anti-static flame-retardant polyester mother yarn.

[0041] Example 2

[0042] A method for preparing an anti-static and flame-retardant polyester mother yarn comprises the following steps:

[0043] (1) After mixing, by mass, 6 parts of basic magnesium sulfate whiskers with an average diameter of 0.5 μm and an average length of 8 μm and 5 parts of tetrapod-shaped zinc oxide whiskers with an average diameter of 0.5 μm and an average length of 10 μm, the mixture was vacuum-baked at 400°C for 5 h, and after cooling, the mixture was dispersed in anhydrous ethanol containing sodium hexametaphosphate at a concentration of 0.04% and stirred and sheared for 40 min, and subjected to normal pressure plasma treatment for 15 min; the mixture was then filtered, and the resulting precipitate was dispersed in water containing calcium stearate at a concentration of 0.2% and ultrasonicated at 65°C for 30 min, and the suspended whiskers on the upper layer of the solution were filtered through 200 mesh, and the operation was repeated 5 times until the filtration was clear, and all the suspended whiskers obtained by filtration were dried to obtain modified antistatic whiskers;

[0044] (2) 8 parts by mass of modified antistatic whiskers, 7 parts by mass of intumescent flame retardant (melamine urate), 1 part by mass of microencapsulated red phosphorus flame retardant, 1.5 parts by mass of silane coupling agent (KH-550) and 0.3 parts by mass of nonionic surfactant (pentaerythritol stearate) were mixed and stirred at 80°C for 50 min to obtain a mixture. 5 parts by mass of the mixture and 0.3 parts by mass of sodium hexametaphosphate were added to 6 parts by mass of ethylene glycol and ultrasonically dispersed at 55°C for 3 h to obtain an antistatic flame retardant whisker dispersion.

[0045] (3) According to the parts by mass, 35 parts of antistatic flame retardant whisker dispersion and 65 parts of ethylene terephthalate are mixed in an esterification kettle, and first undergo an esterification reaction: an esterification temperature of 250°C, a pressure of 70KPa, and an esterification degree of 90%; a second esterification temperature of 253°C, a pressure of 20KPa, and an esterification degree of 96%; and then undergo a polycondensation reaction: a pre-shrinkage temperature of 260-265°C, a pressure of 12KPa, and an acid value of 1000 mol / ton; a second pre-shrinkage temperature of 269-270°C, a pressure of 1.4KPa, and an acid value of 460 mol / ton; a third final polycondensation temperature of 275-277°C, a pressure of 240Pa, and an acid value of 30 mol / ton, to obtain an antistatic flame retardant polyester melt.

[0046] (4) The anti-static flame-retardant polyester melt is spun after melt conveying, with a spinning temperature of 276-278°C, and is spun through a porous spinneret (micropore diameter of 0.6 mm, depth of 1 mm) to obtain a filament bundle; the filament bundle is first cooled by side blowing, the wind speed of the side blowing is 0.7 m / s, the wind temperature is 16°C, and the filament bundle cooling height is 3 m; then it is oiled by an oil tanker (diameter of 350 mm), and then stretched by two rollers, the temperature of the first hot roller is 110-113°C, the filament bundle is wound on the first hot roller for 11 turns, the stretching ratio is 3.3, the speed is 1300 m / min, the temperature of the second hot roller is 120-123°C, the filament bundle is wound on the second hot roller for 8 turns; finally, it is wound at a winding speed of 3900 m / min and a winding tension of 45 cN to obtain the anti-static flame-retardant polyester mother yarn.

[0047] Example 3

[0048] The difference from Example 1 is that the modified antistatic whiskers undergo a post-treatment process.

[0049] A method for preparing an anti-static and flame-retardant polyester mother yarn comprises the following steps:

[0050] (1) After mixing, by weight, 7 parts of basic magnesium sulfate whiskers with an average diameter of 0.6 μm and an average length of 10 μm and 5 parts of tetrapod-shaped zinc oxide whiskers with an average diameter of 0.5 μm and an average length of 8 μm, the mixture was vacuum-baked at 420° C. for 5 h, and after cooling, the mixture was dispersed in anhydrous ethanol containing sodium hexametaphosphate at a concentration of 0.03%, stirred and sheared for 40 min, and subjected to normal pressure plasma treatment for 20 min; the mixture was then filtered, and the resulting precipitate was dispersed in water containing calcium stearate at a concentration of 0.2% and ultrasonicated at 60° C. for 35 min, and the suspended whiskers on the upper layer of the solution were filtered through 200 mesh, and the operation was repeated 4 times until the filtration was clear, and all the suspended whiskers obtained by filtration were dried to obtain modified antistatic whiskers;

[0051] (2) The modified antistatic whiskers were subjected to a post-treatment process: the modified antistatic whiskers were dispersed in 0.10 g / mL water containing 2-amino-5-guanidine-valeric acid, so that the mass volume ratio of the modified antistatic whiskers and the water containing 2-amino-5-guanidine-valeric acid was 0.1 g:7 mL, and then subjected to normal pressure plasma treatment, and then filtered to obtain a filtrate; the filtrate, vanillin, and sodium bicarbonate were added to a mixed solvent of methanol and water in a volume ratio of 10:1, heated to reflux reaction for 3.5 h, and then sodium borohydride was added and stirred at 30 ° C for 10 h, so that the filtrate, The mass volume ratio of vanillin, sodium bicarbonate, sodium borohydride and mixed solvent is 1g:5g:0.4g:0.06g:50mL, and then filtered, washed and vacuum dried to obtain a precipitate; the precipitate, triethanolamine oleate and benzoyl peroxide are added to toluene, and the mass volume ratio of the precipitate, triethanolamine oleate, benzoyl peroxide and toluene is 1g:8g:0.3g:50mL, and reacted at 85°C for 7h, and then vacuum distilled, and then added to anhydrous ether to cool and precipitate, and then vacuum dried to obtain modified antistatic whiskers after post-treatment;

[0052] 8 parts by mass of post-treated modified antistatic whiskers, 5 parts of intumescent flame retardant (melamine urate), 1 part of microencapsulated red phosphorus flame retardant, 1 part of silane coupling agent (KH-550) and 0.3 parts of nonionic surfactant (pentaerythritol stearate) were mixed and stirred at 75°C for 60 minutes to obtain a mixture. 5 parts of the mixture and 0.3 parts of sodium hexametaphosphate were added to 5 parts of ethylene glycol and ultrasonically dispersed at 55°C for 4 hours to obtain an antistatic flame retardant whisker dispersion.

[0053] (3) According to the parts by mass, 35 parts of antistatic flame retardant whisker dispersion and 70 parts of ethylene terephthalate are mixed in an esterification kettle, and first undergo an esterification reaction: an esterification temperature of 250°C, a pressure of 70KPa, and an esterification degree of 90%; a second esterification temperature of 253°C, a pressure of 25KPa, and an esterification degree of 96%; and then undergo a polycondensation reaction: a pre-shrinkage temperature of 260-265°C, a pressure of 11KPa, and an acid value of 1000 mol / ton; a second pre-shrinkage temperature of 269-270°C, a pressure of 1.5KPa, and an acid value of 470 mol / ton; a third final polycondensation temperature of 275-277°C, a pressure of 240Pa, and an acid value of 30 mol / ton, to obtain an antistatic flame retardant polyester melt.

[0054] (4) The anti-static flame-retardant polyester melt is spun after melt conveying, and the spinning temperature is 276-278°C. The yarn is spun through a porous spinneret (micropore diameter is 0.5 mm, and depth is 1.5 mm) to obtain a yarn bundle; the yarn bundle is first cooled by side blowing, the wind speed of the side blowing is 0.8 m / s, the wind temperature is 17°C, and the yarn bundle cooling height is 2.5 m; then it is oiled by an oil tanker (diameter is 400 mm), and then stretched by two rollers, the temperature of the first hot roller is 112-115°C, the yarn bundle is wound on the first hot roller for 12 turns, the stretching ratio is 3.4, the speed is 1250 m / min, the temperature of the second hot roller is 122-125°C, the yarn bundle is wound on the second hot roller for 9 turns; finally, it is wound, the winding speed is 4000 m / min, and the winding tension is 55 cN to obtain the anti-static flame-retardant polyester mother yarn.

[0055] Example 4

[0056] The difference from Example 1 is that the modified antistatic whiskers undergo a post-treatment process.

[0057] A method for preparing an anti-static and flame-retardant polyester mother yarn comprises the following steps:

[0058] (1) After mixing, by weight, 7 parts of basic magnesium sulfate whiskers with an average diameter of 0.6 μm and an average length of 10 μm and 5 parts of tetrapod-shaped zinc oxide whiskers with an average diameter of 0.5 μm and an average length of 8 μm, the mixture was vacuum-baked at 420° C. for 5 h, and after cooling, the mixture was dispersed in anhydrous ethanol containing sodium hexametaphosphate at a concentration of 0.03%, stirred and sheared for 40 min, and subjected to normal pressure plasma treatment for 20 min; the mixture was then filtered, and the resulting precipitate was dispersed in water containing calcium stearate at a concentration of 0.2% and ultrasonicated at 60° C. for 35 min, and the suspended whiskers on the upper layer of the solution were filtered through 200 mesh, and the operation was repeated 4 times until the filtration was clear, and all the suspended whiskers obtained by filtration were dried to obtain modified antistatic whiskers;

[0059] (2) The modified antistatic whiskers were subjected to a post-treatment process: the modified antistatic whiskers were dispersed in 0.12 g / mL water containing 2-amino-5-guanidine-valeric acid, so that the mass volume ratio of the modified antistatic whiskers and the water containing 2-amino-5-guanidine-valeric acid was 0.1 g:6 mL, and then subjected to normal pressure plasma treatment, and then filtered to obtain a filtrate; the filtrate, vanillin, and sodium bicarbonate were added to a mixed solvent of methanol and water in a volume ratio of 10:1, heated to reflux reaction for 4 h, and then sodium borohydride was added and stirred at 30 ° C for 8.5 h to obtain the filtrate, The mass volume ratio of vanillin, sodium bicarbonate, sodium borohydride and mixed solvent is 1g:6g:0.4g:0.07g:50mL, and then filtered, washed and vacuum dried to obtain a precipitate; the precipitate, triethanolamine oleate and benzoyl peroxide are added to toluene, and the mass volume ratio of the precipitate, triethanolamine oleate, benzoyl peroxide and toluene is 1g:6g:0.3g:50mL, and reacted at 90°C for 6h, and then vacuum distilled, and then added to anhydrous ether to cool and precipitate, and then vacuum dried to obtain modified antistatic whiskers after post-treatment;

[0060] 8 parts by mass of post-treated modified antistatic whiskers, 5 parts of intumescent flame retardant (melamine urate), 1 part of microencapsulated red phosphorus flame retardant, 1 part of silane coupling agent (KH-550) and 0.3 parts of nonionic surfactant (pentaerythritol stearate) were mixed and stirred at 75°C for 60 minutes to obtain a mixture. 5 parts of the mixture and 0.3 parts of sodium hexametaphosphate were added to 5 parts of ethylene glycol and ultrasonically dispersed at 55°C for 4 hours to obtain an antistatic flame retardant whisker dispersion.

[0061] (3) According to the parts by mass, 35 parts of antistatic flame retardant whisker dispersion and 70 parts of ethylene terephthalate are mixed in an esterification kettle, and first undergo an esterification reaction: an esterification temperature of 250°C, a pressure of 70KPa, and an esterification degree of 90%; a second esterification temperature of 253°C, a pressure of 25KPa, and an esterification degree of 96%; and then undergo a polycondensation reaction: a pre-shrinkage temperature of 260-265°C, a pressure of 11KPa, and an acid value of 1000 mol / ton; a second pre-shrinkage temperature of 269-270°C, a pressure of 1.5KPa, and an acid value of 470 mol / ton; a third final polycondensation temperature of 275-277°C, a pressure of 240Pa, and an acid value of 30 mol / ton, to obtain an antistatic flame retardant polyester melt.

[0062] (4) The anti-static flame-retardant polyester melt is spun after melt conveying, and the spinning temperature is 276-278°C. The yarn is spun through a porous spinneret (micropore diameter is 0.5 mm, and depth is 1.5 mm) to obtain a yarn bundle; the yarn bundle is first cooled by side blowing, the wind speed of the side blowing is 0.8 m / s, the wind temperature is 17°C, and the yarn bundle cooling height is 2.5 m; then it is oiled by an oil tanker (diameter is 400 mm), and then stretched by two rollers, the temperature of the first hot roller is 112-115°C, the yarn bundle is wound on the first hot roller for 12 turns, the stretching ratio is 3.4, the speed is 1250 m / min, the temperature of the second hot roller is 122-125°C, the yarn bundle is wound on the second hot roller for 9 turns; finally, it is wound, the winding speed is 4000 m / min, and the winding tension is 55 cN to obtain the anti-static flame-retardant polyester mother yarn.

[0063] Comparative Example 1

[0064] The difference from Example 1 is that the spinning temperature is too high.

[0065] A method for preparing an anti-static flame-retardant polyester mother yarn, comprising:

[0066] The anti-static flame-retardant polyester melt is spun after melt conveying, the spinning temperature is 286-288°C, and the yarn is spun through a porous spinneret (micropore diameter is 0.5mm, and depth is 1.5mm) to obtain a yarn bundle; the yarn bundle is first cooled by side blowing, the wind speed of the side blowing is 0.8m / s, the wind temperature is 17°C, and the yarn bundle cooling height is 2.5m; then it is oiled by an oil tanker (diameter is 400mm), and then stretched with two rollers, the temperature of the first hot roller is 112-115°C, the yarn bundle is wound on the first hot roller for 12 turns, the stretching ratio is 3.4, the speed is 1250m / min, the temperature of the second hot roller is 122-125°C, the yarn bundle is wound on the second hot roller for 9 turns; finally, it is wound at a winding speed of 4000m / min and a winding tension of 55cN to obtain the anti-static flame-retardant polyester mother yarn.

[0067] Comparative Example 2

[0068] The difference from Example 1 is that the temperatures of the two heating rollers are different, the temperature of the first heating roller is too low, and the temperature of the second heating roller is too high.

[0069] A method for preparing an anti-static flame-retardant polyester mother yarn, comprising:

[0070] The anti-static flame-retardant polyester melt is spun after melt conveying, with a spinning temperature of 276-278°C, and is spun through a porous spinneret (micropore diameter of 0.5 mm, depth of 1.5 mm) to obtain a tow; the tow is first cooled by side-blowing, with a wind speed of 0.8 m / s, a wind temperature of 17°C, and a tow cooling height of 2.5 m; then, after being oiled by an oil tanker (diameter of 400 mm), two-roller stretching is performed, with the temperature of the first hot roller being 105-108°C, the tow is wound 12 times on the first hot roller, with a stretch ratio of 3.4 and a speed of 1250 m / min, the temperature of the second hot roller being 127-130°C, the tow is wound 9 times on the second hot roller; finally, the tow is wound at a winding speed of 4000 m / min and a winding tension of 55 cN to obtain the anti-static flame-retardant polyester mother yarn.

[0071] Comparative Example 3

[0072] The difference from Example 3 is that triethanolamine oleate is not grafted.

[0073] The modified antistatic whiskers undergo a post-treatment process: the modified antistatic whiskers are dispersed in 0.10 g / mL water containing 2-amino-5-guanidine-valeric acid, so that the mass volume ratio of the modified antistatic whiskers and the water containing 2-amino-5-guanidine-valeric acid is 0.1 g:7 mL, and then subjected to normal pressure plasma treatment, and then filtered to obtain a filtrate; the filtrate, vanillin, and sodium bicarbonate are added to a mixed solvent of methanol and water with a volume ratio of 10:1, heated to reflux reaction for 3.5 hours, and then sodium borohydride is added and stirred at 30°C for 10 hours, so that the mass volume ratio of the filtrate, vanillin, sodium bicarbonate, sodium borohydride and mixed solvent is 1 g:5 g:0.4 g:0.06 g:50 mL, and then filtered, washed, and vacuum dried to obtain post-treated modified antistatic whiskers.

[0074] Comparative Example 4

[0075] The difference from Example 3 is that an excessive amount of triethanolamine oleate is grafted.

[0076] The modified antistatic whiskers were subjected to a post-treatment process: the modified antistatic whiskers were dispersed in 0.10 g / mL water containing 2-amino-5-guanidine-valeric acid, so that the mass volume ratio of the modified antistatic whiskers and the water containing 2-amino-5-guanidine-valeric acid was 0.1 g:7 mL, and then subjected to normal pressure plasma treatment, and then filtered to obtain a filtrate; the filtrate, vanillin, and sodium bicarbonate were added to a mixed solvent of methanol and water in a volume ratio of 10:1, heated to reflux reaction for 3.5 h, and then sodium borohydride was added and stirred at 30 ° C for 10 h, so that the filtrate, vanillin, and sodium bicarbonate were mixed. The mass volume ratio of aldehyde, sodium bicarbonate, sodium borohydride and mixed solvent is 1g:5g:0.4g:0.06g:50mL, and then after filtering, washing and vacuum drying, a precipitate is obtained; the precipitate, triethanolamine oleate and benzoyl peroxide are added to toluene, and the mass volume ratio of the precipitate, triethanolamine oleate, benzoyl peroxide and toluene is 1g:13g:0.3g:50mL, and the reaction is carried out at 85°C for 7h, and then after reduced pressure distillation, the mixture is added to anhydrous ether and cooled to precipitate, and then vacuum dried to obtain modified antistatic whiskers after post-treatment;

[0077] Comparative Example 5

[0078] The difference from Example 3 is that the concentration of water containing 2-amino-5-guanidine-pentanoic acid is too high.

[0079] The modified antistatic whiskers were subjected to a post-treatment process: the modified antistatic whiskers were dispersed in 0.20 g / mL water containing 2-amino-5-guanidine-valeric acid, so that the mass volume ratio of the modified antistatic whiskers and the water containing 2-amino-5-guanidine-valeric acid was 0.1 g:7 mL, and then subjected to normal pressure plasma treatment, and then filtered to obtain a filtrate; the filtrate, vanillin and sodium bicarbonate were added to a mixed solvent of methanol and water in a volume ratio of 10:1, heated to reflux reaction for 3.5 hours, and then sodium borohydride was added and stirred at 30°C for 10 hours to obtain the filtrate, vanillin and sodium bicarbonate. The mass volume ratio of oxalaldehyde, sodium bicarbonate, sodium borohydride and mixed solvent is 1g:5g:0.4g:0.06g:50mL, and then after filtering, washing and vacuum drying, a precipitate is obtained; the precipitate, triethanolamine oleate and benzoyl peroxide are added to toluene, and the mass volume ratio of the precipitate, triethanolamine oleate, benzoyl peroxide and toluene is 1g:8g:0.3g:50mL, and the reaction is carried out at 85°C for 7h, and then after reduced pressure distillation, the mixture is added to anhydrous ether and cooled to precipitate, and then vacuum dried to obtain modified antistatic whiskers after post-treatment;

[0080] Examples 1-4 and Comparative Examples 1-5 were subjected to performance tests according to the relevant test standards of GB / T 14189-2015 fiber-grade polyester chips (PET) and FZ / T54086-2016 flame-retardant polyester drawn yarn. The specific results are shown in Table 1:

[0081] Table 1

[0082]

[0083] As shown in Table 1, the present invention optimizes various process parameters during polyester melt spinning to overcome the difficulties in spinning, cooling uniformity, stretching uniformity, winding, and oiling encountered in existing production processes. This results in a polyester mother yarn with stable flame retardancy, environmental friendliness, and excellent post-processing properties. Comparative Examples 1 and 2 demonstrate that the spinning temperature and the temperature of the double-roll stretching affect the properties of the polyester mother yarn. Optimal results can only be achieved when these temperatures are controlled within the specified ranges of the present invention.

[0084] In addition, a comparison between Example 1 and Examples 3-4 shows that the modified antistatic whiskers after post-treatment can further optimize the local lubrication interface, improve the compatibility with the polyester matrix, the dispersion of the flame retardant, and the fluidity of the melt, and ultimately improve the breaking strength, elongation at break, and flame retardant properties of the polyester mother yarn. As shown in Comparative Examples 3-4, triethanolamine oleate helps optimize the local lubrication interface, but excessive grafting can lead to disadvantages such as excessive viscosity and poor dispersion of the additive, resulting in a decrease in the performance of the polyester mother yarn. As shown in Comparative Example 5, the concentration of 2-amino-5-guanidine-pentanoic acid affects its loading on the whiskers. Increasing groups such as amino and guanidine groups can also lead to excessive local grafting and poor dispersion of the flame retardant, resulting in a decrease in the performance of the polyester mother yarn.

[0085] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any simple modification, change and equivalent structural transformation made to the above embodiment based on the technical essence of the present invention still fall within the scope of protection of the technical solution of the present invention.

Claims

1. A method for preparing anti-static and flame-retardant polyester mother yarn, characterized in that: include: Sodium hexametaphosphate and calcium stearate were used to modify basic magnesium sulfate whiskers and tetrapod-shaped zinc oxide whiskers to obtain modified antistatic whiskers. The modified antistatic whiskers are dispersed in water containing 2-amino-5-guanidine-pentanoic acid, subjected to plasma treatment, and filtered to obtain a filtrate; the filtrate, vanillin, and sodium bicarbonate are added to a mixed solvent of methanol and water, heated under reflux for 3-4 hours, and sodium borohydride is added and stirred to obtain a precipitate; the precipitate, triethanolamine oleate, and benzoyl peroxide are added to toluene and reacted at 80-90° C. to obtain post-treated modified antistatic whiskers; an intumescent flame retardant and a microencapsulated red phosphorus flame retardant are dispersed in the post-treated modified antistatic whiskers and in-situ polymerized with PTA and ethylene glycol to obtain an antistatic flame-retardant polyester melt; The anti-static flame-retardant polyester melt is spun at 276-278°C and spun through a porous spinneret to obtain a tow. The tow is cooled by side-blowing air and oiled by a tanker, and then stretched by two rollers. The temperature of the first hot roller is 110-115°C, the stretching ratio is 3.3-3.6, the speed is 1200-1300 m / min, and the temperature of the second hot roller is 120-125°C. Finally, it is wound.

2. The method for preparing the anti-static and flame-retardant polyester mother yarn according to claim 1, wherein: The micropores of the porous spinneret have a diameter of 0.5-0.7 mm and a depth of 1-2 mm; the wind speed of the side-blowing air is 0.7-0.85 m / s, the wind temperature is 16-18°C, and the cooling height of the filament bundle is 2-3 m; the diameter of the oil tanker is 250-500 mm; the filament bundle is wound around the first hot roller for 10-12 turns, and around the second hot roller for 8-10 turns; the winding speed is 3900-4100 m / min, and the winding tension is 40-60 cN.

3. The method for preparing the anti-static and flame-retardant polyester mother yarn according to claim 1, characterized in that: The preparation method of the anti-static flame-retardant polyester melt comprises the following steps: (1) Mixing basic magnesium sulfate whiskers and tetrapod-shaped zinc oxide whiskers, calcining the mixture in vacuum, dispersing the mixture in anhydrous ethanol containing sodium hexametaphosphate, and subjecting the mixture to atmospheric pressure plasma treatment; filtering the mixture, dispersing the resulting precipitate in water containing calcium stearate, ultrasonicating the mixture, filtering the mixture, and drying the mixture to obtain modified antistatic whiskers; (2) The modified antistatic whiskers are dispersed in water containing 2-amino-5-guanidine-pentanoic acid and subjected to normal pressure plasma treatment, and then filtered to obtain a filtrate; the filtrate, vanillin, and sodium bicarbonate are added to a mixed solvent of methanol and water, heated to reflux reaction for 3-4 hours, and then sodium borohydride is added and stirred at 30-40°C for 8-10 hours, and then filtered, washed, and vacuum dried to obtain a precipitate; the precipitate, triethanolamine oleate, and benzoyl peroxide are added to toluene, reacted at 80-90°C for 5-8 hours, and then vacuum distilled, added to anhydrous ether for cooling and precipitation, and then vacuum dried to obtain a post-treated modified antistatic whisker; the post-treated modified antistatic whisker, an intumescent flame retardant, a microencapsulated red phosphorus flame retardant, a silane coupling agent, and a nonionic surfactant are mixed to obtain a mixture, and then the mixture and sodium hexametaphosphate are added to ethylene glycol for ultrasonic dispersion to obtain an antistatic flame retardant whisker dispersion; (3) The anti-static flame-retardant whisker dispersion and ethylene terephthalate are mixed, and subjected to esterification and polycondensation to obtain an anti-static flame-retardant polyester melt.

4. The method for preparing the anti-static and flame-retardant polyester mother yarn according to claim 3, characterized in that: In step (1), the mass ratio of the basic magnesium sulfate whiskers to the four-needle zinc oxide whiskers is 4-8:2-6; the average diameter of the basic magnesium sulfate whiskers is 0.1-1 μm, and the average length is 5-12 μm; the average diameter of the four-needle zinc oxide whiskers is 0.1-0.8 μm, and the average length is 6-10 μm.

5. The method for preparing the anti-static and flame-retardant polyester mother yarn according to claim 3 or 4, characterized in that: In step (1), the vacuum calcination is carried out at 350-450° C. for 4-6 hours.

6. The method for preparing the anti-static and flame-retardant polyester mother yarn according to claim 3, characterized in that: In step (2), the mass volume ratio of the modified antistatic whisker and the water containing 2-amino-5-guanidine-valeric acid is 0.1 g:6~10 mL; the concentration of the water containing 2-amino-5-guanidine-valeric acid is 0.08~0.12 g / mL; the mass volume ratio of the filtrate, vanillin, sodium bicarbonate, sodium borohydride and mixed solvent is 1 g:3~6 g:0.2~0.5 g:0.05~0.1 g:50 mL; the volume ratio of methanol and water in the mixed solvent is 10:1~2; the mass volume ratio of the precipitate, triethanolamine oleate, benzoyl peroxide and toluene is 1 g:4~9 g:0.2~0.4 g:50 mL.

7. The method for preparing the anti-static and flame-retardant polyester mother yarn according to claim 3, characterized in that: In step (2), the mass ratio of the post-treated modified antistatic whiskers, intumescent flame retardant, microencapsulated red phosphorus flame retardant, silane coupling agent and non-ionic surfactant is 6-10:4-8:1-2:0.5-1.5:0.1-0.3; the mixing is carried out by stirring at 70-80°C for 45-60 minutes; the mass ratio of the mixture, sodium hexametaphosphate and ethylene glycol is 4-6:0.1-0.3:4-6; and the ultrasonic dispersion is carried out by ultrasonic dispersion at 50-60°C for 2.5-5 hours.

8. The method for preparing the anti-static and flame-retardant polyester mother yarn according to claim 3, characterized in that: In step (3), the mass ratio of the anti-static flame retardant whisker dispersion to ethylene terephthalate is 30-40:60-70.

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