Low-residue high-temperature-resistant special cap oil for chemical fiber spinneret cap, preparation method and application

Abstract

This invention provides a low-carbon, high-temperature resistant spinneret cleaning oil for chemical fibers, its preparation method, and its application. The cleaning oil has a carbon residue of ≤0.02%, is thermally stable at 280℃, and has a kinematic viscosity (40℃) of 9.0~11.0 mm. 2 / s; mainly composed of hydroisolated dewaxed base oil (75wt%~88wt%), a mixture of trimethylolpropane ester (TMP ester) and diethylene glycol monobutyl ether (8.0wt%~17.0wt%), polyisobutylene succinimide (1.5%~3.5%), at least one of benzotriazole (BTA) and toluenetriazole (0.1wt%~0.3wt%), at least one of high-temperature phenolic antioxidants and phosphites (0.2wt%~0.6wt%), polyether-modified siloxane (0.01wt%~0.05wt%), and food-grade white oil. Technical benefits: High cleaning efficiency, needle passage rate ≥99.5%; ultra-low residue (residual carbon ≤0.02%), extending the lifespan of the spinneret and continuous spinning time; no corrosion, discoloration, or hydrogen embrittlement risk to stainless steel, titanium alloys, and electroplated layers; safe and environmentally friendly, flash point ≥65℃, meeting workshop safety and environmental emission requirements, and complying with RoHS and REACH environmental requirements; can be used online, shortening downtime for maintenance.

Description

Technical Field

[0001] This invention belongs to the field of precision cleaning technology for chemical fiber spinning equipment, specifically relating to a special cleaning and wiping oil suitable for the micropores of spinnerets / spinning plates in chemical fiber spinning, especially suitable for online / offline wiping, descorching, degelling, anti-clogging and rust prevention of the micropores of spinnerets / spinning plates of 0.15~0.4mm cellulose acetate spinning. Background Technology

[0002] The spinning assembly is the core of spinning, and the spinneret is the core of that core. Fiber acetate tow, due to its excellent physical properties and superior filtration of harmful substances, is widely used in cigarette filters. Fiber acetate (short for cellulose acetate fiber) is produced by esterification of cellulose acetate esters with acetic acid as a solvent and acetic anhydride as an acetylation agent under the action of a catalyst. The fibers are then spun. Because the molecular structure of cellulose acetate contains a large number of hydroxyl and carboxyl groups, forming strong intermolecular entanglement, it increases the processing difficulty. Typically, cellulose acetate tow production involves filtering and pressurizing a prepared flowable slurry, then extruding it through the spinneret of a spinning machine, followed by post-processing to form cellulose acetate tow for cigarettes. The spinneret has numerous orifices, whose function is to transform the viscous polymer into a fine stream with a specific cross-sectional shape, which is then solidified into filaments. The spinneret is a precision mechanical component with high accuracy, significantly impacting the spinning quality. Because the slurry has a certain viscosity, if the spinning machine stops, all the spinnerets on the spinning machine must be removed, cleaned and inspected before being used again when the machine is restarted.

[0003] Furthermore, during the high-temperature melt spinning process of synthetic fibers, the spinneret is prone to adhering to melt degradation particles, oligomers, gels, oil, and dust. Once the micropores of the spinneret are blocked or damaged into a deformed shape, it will lead to uneven distribution of the spun yarn density, thus affecting product quality. To ensure spinning quality, the spinneret is usually removed and wiped with a cleaning oil to remove dirt.

[0004] Current conventional cleaning technologies employ halogenated solvents such as trichloroethylene / dichloromethane, industrial gasoline, kerosene, ordinary machine oil, and ultrasonic alkaline cleaning. However, using halogenated solvents as cleaning oils presents several drawbacks: high toxicity, high VOC content, equipment corrosion, environmental restrictions, and potential health hazards. Using gasoline / kerosene results in low flash point, flammability and explosiveness, insufficient cleaning power, and residues that can cause secondary coking. Using ordinary machine oil leads to high viscosity, high carbon residue, clogging of micropores, and increased coking at high temperatures, making it difficult to remove. Alkaline cleaning / ultrasonic cleaning requires disassembly and offline operation, resulting in long downtime and potential corrosion damage to micropores and the electroplated layer. Therefore, these conventional cleaning agents and methods fail to simultaneously meet multiple requirements, including micropore penetration, coke dissolution, low carbon residue, high temperature resistance, rust prevention, and quick drying, making them unsuitable for cleaning spinning caps.

[0005] Specialized spinneret cleaning oils are extremely scarce. Existing technologies, such as the spinneret cleaning agents disclosed in CN104726225A and CN108929802A, are water-based or acidic cleaning systems suitable for immersion / ultrasonic cleaning, requiring spinneret cap disassembly and unsuitable for online wiping. Furthermore, they cannot simultaneously meet requirements such as low residual carbon (≤0.02%), high temperature resistance (≥280℃), zero microporous residue, metal corrosion inhibition, and low VOC safe wiping. Therefore, there is an urgent need to find a specialized spinneret cleaning oil, preparation method, and application that can achieve both low residual carbon, strong microporous penetration, high temperature resistance, and zero corrosion, thus providing cleaning and protection for spinnerets. Summary of the Invention

[0006] In order to overcome the above-mentioned technical problems, the purpose of this invention is to: (1) provide a special wiping oil for spinnerets that can take into account low residual carbon, strong microporous penetration, high temperature resistance, zero corrosion, and realize the cleaning and protection functions of spinnerets; (2) provide a method for preparing the above-mentioned special wiping oil for spinnerets that can be mass-produced industrially; (3) provide an application method for the above-mentioned special wiping oil for spinnerets that simplifies the process and greatly shortens the downtime maintenance time.

[0007] To achieve the above-mentioned objectives, this invention provides a low-carbon, high-temperature resistant spinneret oil specifically for cleaning caps. The oil has a carbon residue of ≤0.02%, exhibits thermal stability at 280℃, and has a kinematic viscosity of 9.0~11.0 mm² / s at 40℃. The oil is mainly composed of hydrotreated isomerized dewaxed base oil, solubilizers, dispersants, metal corrosion inhibitors, antioxidant stabilizers, defoamers, and regulators.

[0008] Furthermore, in the low-carbon, high-temperature resistant spinneret oil for chemical fibers provided by this invention, the hydrotreated isomerized dewaxing base oil accounts for 75wt%~88wt% by mass; the solubilizing and penetrating agent is a mixture of trimethylolpropane ester (TMP) and diethylene glycol monobutyl ether, accounting for 8.0wt%~17.0wt% by mass; the dispersant is polyisobutylene succinimide, accounting for 1.5%~3.5% by mass; the metal corrosion inhibitor is at least one of benzotriazole (BTA) and toluenetriazole, accounting for 0.1wt%~0.3wt% by mass; the antioxidant stabilizer is at least one of high-temperature phenolic antioxidant and phosphite, accounting for 0.2wt%~0.6wt% by mass; the defoamer is polyether-modified siloxane, accounting for 0.01wt%~0.05wt% by mass; and the regulator is food-grade white oil.

[0009] Furthermore, in the low-carbon, high-temperature resistant chemical fiber spinneret cleaning oil provided by this invention, trimethylolpropane ester (TMP ester) accounts for 6wt%~12wt% of the cleaning oil by mass; diethylene glycol monobutyl ether accounts for 2.0wt%~5.0wt% of the cleaning oil by mass.

[0010] To achieve the above-mentioned objectives, this invention also provides a method for preparing any of the above-mentioned low-carbon, high-temperature resistant chemical fiber spinneret cleaning oils, comprising the following steps:

[0011] S1. Base oil pretreatment: The hydroisomerized dewaxed base oil is added to a closed reactor, heated, and stirred to remove gas; the mass percentage of the hydroisomerized dewaxed base oil in the capping oil is 75wt%~88wt%;

[0012] S2. High-temperature dispersion and dissolution: Add TMP ester, diethylene glycol monobutyl ether, and dispersant, and stir to disperse and dissolve; the mass percentage of TMP ester in the cap polishing oil is 6wt%~12wt%; the mass percentage of diethylene glycol monobutyl ether in the cap polishing oil is 2.0wt%~5.0wt%; the dispersant is polyisobutylene succinimide, with a mass percentage of 1.5%~3.5% in the cap polishing oil;

[0013] S3. Cooling and Compounding: Cool down, add antioxidant stabilizer, metal corrosion inhibitor, defoamer, and regulator, and stir until uniform and transparent; the metal corrosion inhibitor is at least one of benzotriazole (BTA) and toluenetriazole, with a dosage of 0.1wt%~0.3wt%; the antioxidant stabilizer is at least one of high-temperature phenolic antioxidant and phosphite, with a dosage of 0.2wt%~0.6wt%; the defoamer is polyether-modified siloxane, with a dosage of 0.01wt%~0.05wt%; the regulator is food-grade white oil.

[0014] S4. Precision filtration: Three-stage precision filtration removes mechanical impurities and avoids scratching the micropores.

[0015] Furthermore, in the method for preparing a low-carbon, high-temperature resistant chemical fiber spinneret oil provided by the present invention, in the S1 "base oil pretreatment" step, the temperature after heating is 55~65℃; in the S3 "cooling and compounding" step, the temperature after cooling is 40~45℃.

[0016] Furthermore, in the method for preparing a low-carbon, high-temperature resistant chemical fiber spinneret oil provided by the present invention, in step S4 "precision filtration", the three-stage precision filtration is 5μm→1μm→0.45μm.

[0017] To achieve the above-mentioned objectives, this invention also provides the application of any of the above-mentioned low-carbon, high-temperature resistant chemical fiber spinneret oils or the low-carbon, high-temperature resistant chemical fiber spinneret oils prepared according to any of the above-mentioned preparation methods, or their application in offline wiping, online wiping, or automatic wiping machines.

[0018] Furthermore, in the application of the low-carbon, high-temperature resistant chemical fiber spinneret cleaning oil provided by this invention, offline wiping includes the following steps:

[0019] S11. Remove the spinneret cap and cool to 60~80℃;

[0020] S12. Apply cleaning oil to the plate surface and micropores with a lint-free cloth / microfiber rod;

[0021] S13. After the char body is dissolved, wipe it clean with a clean cloth. No water washing is required.

[0022] Furthermore, in the application of the low-carbon, high-temperature resistant chemical fiber spinneret cleaning oil provided by this invention, the online wiping process includes the following steps:

[0023] S21. Stop the machine without removing the spinneret cap;

[0024] S22. When the spinneret is hot (not exceeding 280°C), quickly wipe the spinneret with a sponge oil.

[0025] S23, the oil film dries quickly without residue, and spinning can be resumed directly.

[0026] Furthermore, in the application of the low-carbon, high-temperature resistant chemical fiber spinneret oil provided by this invention, the automatic cleaning machine is used as follows: the cleaning oil is applied according to the requirements of the automatic cleaning machine, and vacuum suction is used to achieve automated cleaning.

[0027] The technical effects of this invention are as follows: (1) High cleaning efficiency. The removal rate of coke particles, gels and oligomers is ≥99%, and the micropore needle passage rate is ≥99.5%, which significantly reduces broken filaments, fuzz and defects. (2) Ultra-low residue. Residual carbon ≤0.02%, no coking at high temperature, extending the service life of the spinneret and continuous spinning time. (3) Material friendly. No corrosion, discoloration and hydrogen embrittlement risk to stainless steel, titanium alloy and electroplated layer. (4) Safe and environmentally friendly. Halogen-free, heavy metal-free and ozone-depleting substances free of ODS, meeting RoHS and REACH environmental protection requirements; low VOC, low odor, flash point ≥65℃, meeting workshop safety and environmental emission requirements. (5) Simplified process. Can be used online / offline, no need to disassemble for alkaline washing and ultrasonic treatment, greatly shortening downtime maintenance time. (6) Excellent stability. No stratification, no precipitation and no deterioration after 12 months of storage at room temperature, suitable for large-scale continuous production. (7) Wide range of applications. It can be used not only in solution spinning production lines for cellulose acetate, but also in mainstream melt spinning production lines for polyester POY / FDY, nylon, polypropylene, etc., and is compatible with imported / domestic spinnerets. Detailed Implementation

[0028] The purpose of this invention is to provide a low-carbon, high-temperature resistant spinneret oil for chemical fibers, solving the following key technical problems: (1) Rapid penetration into 0.15mm micropores, efficiently dissolving coke particles, oligomers, and gels, with a needle-passing rate of ≥99.5% after wiping. (2) Extremely low carbon residue (≤0.02%), no coking or gelling at high temperatures, and no residue, avoiding secondary pore blockage. (3) High temperature resistant, suitable for online hot wiping in spinning, without flash explosion, smoke, or contamination of the melt. (4) No corrosion, hydrogen embrittlement, or discoloration on stainless steel, titanium alloy, and electroplated spinnerets, and also provides process rust prevention. (5) Low VOC, halogen-free, low odor, flash point ≥65℃, meeting the safety and environmental protection requirements of workshops. (6) Suitable for manual wiping with lint-free cloths / cotton swabs and coating with automatic spinneret machines, quick-drying and dust-free.

[0029] The inventive concept of this invention is to use ultra-high purity hydroisolated dewaxing base oil as a carrier, and to compound dispersants, ester cosolvents, metal corrosion inhibitors, antioxidant stabilizers, and defoamers, and through precise formulation and precision filtration processes, to prepare a special cap cleaning oil with low viscosity, low carbon residue, high penetration, and high solubility, thereby achieving deep cleaning of micropores and high-temperature safety protection.

[0030] The low-carbon, high-temperature resistant spinneret oil for chemical fibers provided by this invention is a colorless or light yellow transparent liquid with a carbon residue of ≤0.02%. It has thermal stability at 280℃ and a kinematic viscosity of 9.0~11.0 mm² / s at 40℃. It is mainly composed of ultra-high purity hydrotreated isomerized dewaxed base oil, dispersant, ester cosolvent, metal corrosion inhibitor, antioxidant stabilizer, and defoamer, and also includes regulators.

[0031] Regarding the base oil: Ultra-high purity hydroisomerized dewaxing base oil is selected; its mass percentage in the capping oil formulation is 75.0wt%~88.0wt%, and its core functions include: low viscosity, low carbon residue, high oxidation stability, and high temperature resistance. Hydroisomerized dewaxing base oil with a viscosity of 10 mm² / s at 40℃ is preferred.

[0032] Regarding ester-based solubilizers and penetrants: A mixed solvent of trimethylolpropane ester (TMP ester) and diethylene glycol monobutyl ether is selected. Trimethylolpropane ester accounts for 6.0 wt% to 12.0 wt% of the total coating oil formulation, and its core functions are: strong dissolution of oligomers / gels, and improved microporous penetration; diethylene glycol monobutyl ether accounts for 2.0 wt% to 5.0 wt% of the total coating oil formulation, and its core functions are: solubilization and thickening, reduction of surface tension, and accelerated removal of char.

[0033] Regarding the dispersant: Ash-free polyisobutylene succinimide is selected as the dispersant, which accounts for 1.5wt%~3.5wt% of the total mass of the varnish formulation. Its core functions are: high-temperature dispersion of coke particles, prevention of redeposition, and maintenance of pore permeability.

[0034] Regarding metal corrosion inhibitors: The metal corrosion inhibitor selected is at least one of benzotriazole (BTA) and toluenetriazole, with a mass ratio of 0.1wt%~0.3wt% in the entire capping oil formulation. Its core functions are: corrosion inhibition of stainless steel / titanium alloys, and rust prevention for ≥72 hours during the process.

[0035] Regarding antioxidant stabilizers: High-temperature phenolic antioxidants / phosphites are selected as antioxidant stabilizers, accounting for 0.2wt%~0.6wt% of the total weight of the cap polish formulation. Their core functions are: inhibiting high-temperature oxidation and reducing residual carbon formation.

[0036] Regarding defoamers: The defoamer selected is polyether-modified siloxane, which accounts for 0.01wt%~0.05wt% of the total cap polish formulation. Its core function is to quickly defoam and prevent residual bubbles from forming during wiping.

[0037] Regarding the regulator: The regulator uses food-grade white oil, and its core function is to adjust viscosity and improve coating uniformity.

[0038] Regarding the performance indicators and testing standards of the varnish: Appearance is determined visually; the liquid should be colorless or light yellow and transparent, free of impurities. Kinematic viscosity (40℃) is determined according to GB / T265-1988 "Determination of Kinematic Viscosity and Calculation of Dynamic Viscosity of Petroleum Products". Residual carbon (10% distillation residue) is determined according to GB / T 268-1987 "Determination of Residual Carbon in Petroleum Products (Kondratiev Method)". Copper strip corrosion (100℃, 3h) is tested according to GB / T 5096-2017 "Test Method for Copper Strip Corrosion of Petroleum Products". Titanium alloy corrosion (72h immersion) is visually inspected; no discoloration, pitting, or hydrogen embrittlement is acceptable. Thermal stability (320℃, 2h) is tested using a combination of thermogravimetric analysis and visual inspection; no coking, gumming, or significant weight gain is acceptable. Micropore needle penetration rate is tested using a Φ0.15mm needle.

[0039] The low-carbon, high-temperature resistant spinneret oil for chemical fibers provided by this invention is prepared using the following steps:

[0040] S1. Base oil pretreatment: Add the hydrotreated isomerized base oil into a closed reactor, heat it to 55~65℃, and stir to remove gas.

[0041] S2. Dispersion and dissolution: Add TMP ester, diethylene glycol monobutyl ether, and ashless dispersant, and stir to disperse and dissolve.

[0042] S3, Compounding: Cool to 40~45℃, add antioxidant, corrosion inhibitor and defoamer, and stir until uniform and transparent.

[0043] S4. Precision filtration: Three-stage precision filtration (5μm→1μm→0.45μm) removes mechanical impurities and avoids scratching the micropores.

[0044] S5. Inspection and Filling: Inspect the appearance, viscosity, flash point, residual carbon, and corrosion performance. After passing the inspection, seal and fill with nitrogen.

[0045] The low-carbon, high-temperature resistant chemical fiber spinneret oil provided by this invention, or the low-carbon, high-temperature resistant chemical fiber spinneret oil prepared by the above preparation method, can be used offline, online, or on an automatic spinneret cleaning machine.

[0046] The specific offline usage is as follows: Cool the disassembled spinneret to 60~80℃, apply the spinneret cleaning oil and wipe the plate surface and micropores with a lint-free cloth / microfiber rod. After the coke dissolves, wipe it clean with a clean cloth. No water washing is required.

[0047] The specific online usage is as follows: stop the machine, do not remove the spinneret cap, apply the wiping oil to the cap quickly while it is hot (≤280℃), the oil film dries quickly without residue, and spinning can be resumed directly.

[0048] The specific usage of the automatic hat cleaning machine is as follows: apply hat cleaning oil according to the requirements of the hat cleaning machine, and use vacuum suction to achieve automated cleaning.

[0049] Example 1 (Standard Universal Type)

[0050] All chemical reagents used in this embodiment were commercially available. The following chemical reagents and dosages were used to prepare the varnish: hydrotreated isomer base oil, 82.0 wt%; trimethylolpropane ester (TMP), 9.0 wt%; diethylene glycol monobutyl ether, 3.5 wt%; polyisobutylene succinimide, 2.5 wt%; benzotriazole (BTA), 0.2 wt%; high-temperature phenolic antioxidant, 0.3%; polyether-modified siloxane, 0.03%; and food-grade white oil as the conditioner, 2.47 wt%.

[0051] This Example 1 uses the above-mentioned cap polishing oil formula and prepares the special cap polishing oil according to the following steps:

[0052] S1. Base oil pretreatment: Add hydrotreated isomerized base oil into a closed reactor, heat to 60°C, and stir to remove gas.

[0053] S2. Dispersion and dissolution: Add TMP ester, diethylene glycol monobutyl ether, and polyisobutylene succinimide, and stir to disperse and dissolve.

[0054] S3, Compounding: Cool to 42℃, add high-temperature phenolic antioxidant, benzotriazole, and polyether-modified siloxane, and stir until uniform and transparent.

[0055] S4. Precision filtration: Three-stage precision filtration (5μm→1μm→0.45μm) removes mechanical impurities and avoids scratching the micropores.

[0056] The low-carbon, high-temperature resistant chemical fiber spinneret oil prepared in Example 1 was tested according to the test method described in the specific implementation method. The results are as follows: the kinematic viscosity at 40℃ is 10.2 mm² / s, the carbon residue is 0.018%, it is thermally stable without coking after 2 hours at 320℃, it shows no corrosion after immersion in titanium alloy for 72 hours, and the micropore needle-passing rate is 99.8%.

[0057] Example 2 (High-strength coking material specific type)

[0058] All chemical reagents used in this embodiment were commercially available. To adapt to high-viscosity melts and the cleaning of heavily coked waste from long-cycle spinning, the mass percentage of TMP ester was increased to 12.0%, and the mass percentage of diethylene glycol monobutyl ether was increased to 5.0%. The adjusted composition was: hydrotreated isomer base oil, 75.0 wt%; trimethylolpropane ester (TMP ester), 12.0 wt%; diethylene glycol monobutyl ether, 5 wt%; polyisobutylene succinimide, 3.5 wt%; benzotriazole (BTA), 0.3 wt%; high-temperature phenolic antioxidant, 0.6%; polyether-modified siloxane, 0.05%; and food-grade white oil as the regulator, 3.55 wt%. A low-carbon, high-temperature resistant spinneret oil for chemical fibers was prepared according to the preparation method described in the specific embodiment.

[0059] This Example 2 uses the above-mentioned cap polishing oil formula and prepares a special cap polishing oil according to the same process as Example 1. The only difference is that the base oil treatment temperature is 55°C and the compounding temperature is 40°C.

[0060] The low-carbon, high-temperature resistant chemical fiber spinneret oil prepared in Example 2 was tested according to the test method described in the specific implementation method. The results are as follows: the kinematic viscosity at 40℃ is 9.98 mm² / s, the carbon residue is 0.017%, it is thermally stable without coking after 2 hours at 320℃, it shows no corrosion after immersion in titanium alloy for 72 hours, and the micropore needle-passing rate is 99.9%.

[0061] Example 3 (Low-strength coking compound)

[0062] All chemical reagents used in this embodiment were commercially available. To adapt to low-viscosity melts and the cleaning of mild coking residues in short-cycle spinning, the mass percentage of TMP ester was reduced to 6.0%, and the mass percentage of diethylene glycol monobutyl ether was reduced to 2.0%. The adjusted composition was as follows: hydrotreated isomer base oil, 88.0 wt%; trimethylolpropane ester (TMP ester), 6.0 wt%; diethylene glycol monobutyl ether, 2 wt%; polyisobutylene succinimide, 1.5 wt%; benzotriazole (BTA), 0.1 wt%; high-temperature phenolic antioxidant, 0.2%; polyether-modified siloxane, 0.01%; and food-grade white oil as the regulator, 2.19 wt%. A low-carbon, high-temperature resistant spinneret oil for cleaning caps was prepared according to the preparation method described in the specific embodiment.

[0063] This embodiment uses the above-mentioned cap polishing oil formula and prepares a special cap polishing oil according to the same process as in Example 1. The only difference is that the base oil treatment temperature is 58°C and the compounding temperature is 43°C.

[0064] The low-carbon, high-temperature resistant chemical fiber spinneret oil prepared in this embodiment was tested according to the test method described in the specific embodiment. The results are as follows: the kinematic viscosity at 40℃ is 10.3 mm² / s, the carbon residue is 0.019%, it is thermally stable without coking after 2 hours at 320℃, it does not corrode titanium alloy after 72 hours of immersion, and the micropore needle-passing rate is 99.7%.

[0065] Example 4

[0066] All chemical reagents used in this embodiment were commercially available. The difference from Example 1 is that the metal corrosion inhibitor is toluenetriazole, with a mass percentage of 0.2 wt%; and the antioxidant stabilizer is phosphite, with a mass percentage of 0.3%. Except for the different formulation components, the preparation steps and processes are completely the same as in Example 1.

[0067] The low-carbon, high-temperature resistant chemical fiber spinneret oil prepared in this embodiment was tested according to the test method described in the specific embodiment. The results are as follows: the kinematic viscosity at 40℃ is 10.18 mm² / s, the carbon residue is 0.018%, it is thermally stable without coking after 2 hours at 320℃, it shows no corrosion after immersion in titanium alloy for 72 hours, and the micropore needle penetration rate is 99.8%.

[0068] Example 5

[0069] All chemical reagents used in this embodiment were commercially available. The difference from Example 1 is that the metal corrosion inhibitor is a mixture of benzotriazole (BTA) and toluenetriazole, with a mass percentage of 0.2 wt%; the antioxidant stabilizer is a mixture of high-molecular-weight phenolic antioxidants and phosphites, with a mass percentage of 0.3%. Except for the different formulation components, the preparation steps and processes are completely the same as in Example 1.

[0070] The low-carbon, high-temperature resistant chemical fiber spinneret oil prepared in this embodiment was tested according to the test method described in the specific embodiment. The results are as follows: the kinematic viscosity at 40℃ is 10.19 mm² / s, the carbon residue is 0.018%, it is thermally stable without coking after 2 hours at 320℃, it shows no corrosion after immersion in titanium alloy for 72 hours, and the micropore needle penetration rate is 99.8%.

[0071] Comparative Example 1 (Industrial Gasoline)

[0072] It has a low flash point (≤28℃), is flammable and explosive, has weak dissolving power, high residue, is prone to secondary coking, and has a needle-passing rate of <85%.

[0073] Comparative Example 2 (Regular Engine Oil)

[0074] High residual carbon (≥0.5%) and high viscosity clog micropores, causing severe coking at high temperatures, making it unsuitable for precision cleaning.

Claims

1. A low-carbon, high-temperature resistant oil specifically for cleaning spinnerets of synthetic fibers, characterized in that... The cleaning oil has a carbon residue of ≤0.02%, exhibits thermal stability at 280℃, and has a kinematic viscosity of 9.0~11.0 mm at 40℃. 2 / s; The capping oil is mainly composed of hydrotreated isomerized dewaxed base oil, solubilizer, penetrant, dispersant, metal corrosion inhibitor, antioxidant stabilizer, defoamer and regulator.

2. The low-carbon, high-temperature resistant chemical fiber spinneret cleaning oil as described in claim 1, characterized in that... In the aforementioned varnish, the hydroisolated dewaxing base oil accounts for 75wt%~88wt% by mass; the solubilizing and penetrating agent is a mixture of trimethylolpropane ester (TMP) and diethylene glycol monobutyl ether, accounting for 8.0wt%~17.0wt% by mass; the dispersant is polyisobutylene succinimide, accounting for 1.5%~3.5% by mass; the metal corrosion inhibitor is at least one of benzotriazole (BTA) and toluenetriazole, accounting for 0.1wt%~0.3wt% by mass; the antioxidant stabilizer is at least one of high-temperature phenolic antioxidant and phosphite, accounting for 0.2wt%~0.6wt% by mass; the defoamer is polyether-modified siloxane, accounting for 0.01wt%~0.05wt% by mass; and the regulator is food-grade white oil.

3. The low-carbon, high-temperature resistant chemical fiber spinneret cleaning oil as described in claim 2, characterized in that... The trimethylolpropane ester (TMP ester) accounts for 6 wt% to 12 wt% of the cap polishing oil; the diethylene glycol monobutyl ether accounts for 2.0 wt% to 5.0 wt% of the cap polishing oil.

4. A method for preparing a low-carbon, high-temperature resistant spinneret oil for chemical fibers as described in any one of claims 1 to 3, characterized in that, Including the following steps: S1. Base oil pretreatment: The hydroisomerized dewaxed base oil is added to a closed reactor, heated, and stirred to remove gas; the mass percentage of the hydroisomerized dewaxed base oil in the capping oil is 75wt%~88wt%. S2. High-temperature dispersion and dissolution: Add TMP ester, diethylene glycol monobutyl ether, and dispersant, and stir to disperse and dissolve; the TMP ester accounts for 6wt%~12wt% of the total mass of the cap polishing oil; the diethylene glycol monobutyl ether accounts for 2.0wt%~5.0wt% of the total mass of the cap polishing oil; the dispersant is polyisobutylene succinimide, accounting for 1.5%~3.5% of the total mass of the cap polishing oil; S3. Cooling and Compounding: Cool down, add antioxidant stabilizer, metal corrosion inhibitor, defoamer, and regulator, and stir until uniform and transparent; the metal corrosion inhibitor is at least one of benzotriazole (BTA) and toluenetriazole, with a dosage of 0.1wt%~0.3wt%; the antioxidant stabilizer is at least one of high-temperature phenolic antioxidant and phosphite, with a dosage of 0.2wt%~0.6wt%; the defoamer is polyether-modified siloxane, with a dosage of 0.01wt%~0.05wt%; the regulator is food-grade white oil; S4. Precision filtration: Three-stage precision filtration removes mechanical impurities and avoids scratching the micropores.

5. The method for preparing a low-carbon, high-temperature resistant chemical fiber spinneret cleaning oil as described in claim 4, characterized in that... In the S1 "base oil pretreatment" step, the temperature after heating is 55~65℃; in the S3 "cooling and compounding" step, the temperature after cooling is 40~45℃.

6. The method for preparing a low-carbon, high-temperature resistant chemical fiber spinneret cleaning oil as described in claim 4, characterized in that... In step S4, "precision filtration", the three-stage precision filtration is 5μm→1μm→0.45μm.

7. The application of any one of the low-carbon, high-temperature resistant spinneret cleaning oils according to claims 1-4 or the low-carbon, high-temperature resistant spinneret cleaning oil prepared according to any one of the preparation methods according to claims 5-6, characterized in that: Applications include offline wiping, online wiping, and automatic cap wiping machines.

8. The application of the low-carbon, high-temperature resistant chemical fiber spinneret cleaning oil as described in claim 7, characterized in that, The offline wiping process includes the following steps: S11. Remove the spinneret cap and cool to 60~80℃; S12. Apply cleaning oil to the plate surface and micropores with a lint-free cloth / microfiber rod; S13. After the char body is dissolved, wipe it clean with a clean cloth. No water washing is required.

9. The application of the low-carbon, high-temperature resistant chemical fiber spinneret cleaning oil as described in claim 7, characterized in that, The online wiping process includes the following steps: S21. Stop the machine without removing the spinneret cap; S22. When the spinneret is hot (not exceeding 280°C), quickly wipe the spinneret with a sponge oil. S23, the oil film dries quickly without residue, and spinning can be resumed directly.

10. The application of the low-carbon, high-temperature resistant chemical fiber spinneret cleaning oil as described in claim 7, characterized in that, The automatic hat-wiping machine is used to apply hat-wiping oil according to the requirements of the automatic hat-wiping machine, and then use vacuum suction to remove it to achieve automated cleaning.