Preparation method of ultra-high molecular weight polyethylene fiber

Abstract

The invention discloses a preparation method of ultra-high molecular weight polyethylene fibers, and belongs to the technical field of high molecular compound compositions and fiber materials, and the preparation method comprises the following steps: adding ultra-high molecular weight polyethylene powder into a solvent, and dissolving to obtain a spinning solution; adding the spinning solution into a double-screw extruder, and blending and extruding to obtain a spinning solution; filtering the spinning solution, extruding through a spinneret plate to obtain cellosilk, extracting, cleaning, drying, stretching and heat-setting the cellosilk, immersing the cellosilk in a glue solution for a period of time, taking out the cellosilk, cleaning and drying to obtain the ultra-high molecular weight polyethylene fiber. According to the preparation method, the fiber yarns are immersed into the glue solution, and the modified nano aluminum oxide / carbon nanotube composite powder is added into the spinning solution, so that the breaking strength and the wear resistance of the polyethylene fiber are remarkably improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of compositions of high molecular compounds and fiber materials. More specifically, the present invention relates to a method for preparing ultra-high molecular weight polyethylene fibers. Background Art

[0002] Polyethylene fibers are synthetic fibers made from polyethylene by melt spinning or solution spinning. They occupy an important position in the field of high-performance fibers. Polyethylene fibers are formed by the polymerization of a large number of ethylene monomers. The molecular chain is a saturated carbon-carbon main chain and contains a large number of methylene groups (-CH2-). This regular and highly symmetric molecular chain structure enables the polyethylene molecular chains to be closely arranged, thus easily forming a highly crystalline structure. Its crystallinity can usually reach 70% - 90%. The high crystallinity endows the fibers with many excellent properties. Due to the advantages of high strength, high modulus, high wear resistance, corrosion resistance, low density, and excellent impact resistance, polyethylene fibers have a large number of applications in the fields of national defense, aerospace, sports, etc. In the field of national defense, polyethylene fibers are used to manufacture protective equipment such as bulletproof vests, bulletproof helmets, and bulletproof armor, and can also be used to manufacture parachutes, ship cables, radomes, etc.; in the field of aerospace, they can be used to manufacture aircraft wings, fuselage structural parts, satellite antennas, etc., effectively reducing the weight of aircraft and improving the fuel efficiency and performance of aircraft.

[0003] In order to further improve the strength and wear resistance of ultra-high molecular weight polyethylene fibers, the currently commonly used method is to add a polymer wear-resistant coating or add organic or inorganic filler substances to the spinning dope for blending modification. With the development of various fields, the requirements for the performance of fiber materials are becoming increasingly stringent, and the demand for the preparation and production of polyethylene fibers with higher strength and wear resistance has become more urgent. Summary of the Invention

[0004] An object of the present invention is to solve at least the above problems and / or defects and provide at least the advantages described hereinafter.

[0005] To achieve these objects and other advantages in accordance with the present invention, there is provided a method for preparing ultra-high molecular weight polyethylene fibers, comprising the following steps:

[0006] Step 1: Add ultra-high molecular weight polyethylene powder to a solvent and dissolve to obtain a spinning dope;

[0007] Step 2: Add the spinning dope to a twin-screw extruder and co-extrude to obtain a spinning solution;

[0008] Step 3: Filter the spinning solution, extrude it through a spinneret to obtain fiber filaments, extract the fiber filaments, and after cleaning, drying, stretching, and heat setting, immerse them in the glue solution for a period of time, then take them out, clean and dry to obtain ultra-high molecular weight polyethylene fibers.

[0009] Preferably, in the step 1, the weight-average molecular weight of the ultra-high molecular weight polyethylene powder is 3 million to 10 million.

[0010] Preferably, in the step 1, the solvent is decalin, white oil or paraffin oil, and the mass percentage of the polyethylene powder in the solvent is 10% - 20%.

[0011] Preferably, in the step 2, the extrusion temperature of the twin-screw extruder is 130 - 180 °C.

[0012] Preferably, in the step 3, the spinneret diameter of the spinneret is 0.05 - 0.5 mm.

[0013] Preferably, in the step 3, the glue solution includes by weight: 20 - 40 parts of isooctyl acrylate, 5 - 20 parts of polyurethane, 1 - 5 parts of 1,6-hexanediol diacrylate, 5 - 10 parts of bisphenol A epoxy resin, and 1 - 5 parts of bisphenol F epoxy resin.

[0014] Preferably, the preparation method of the glue solution includes:

[0015] S31: Pour isooctyl acrylate into a container, and at a rotation speed of 100 - 200 rpm, keep the isooctyl acrylate in a uniformly flowing state; slowly add polyurethane to the isooctyl acrylate, and continue stirring to fully disperse and dissolve the polyurethane in the isooctyl acrylate. The stirring time is 15 - 30 min to obtain a mixed solution;

[0016] S32: Add 1,6-hexanediol diacrylate to the mixed solution, increase the stirring speed to 300 - 500 rpm, and stir for 10 - 30 min to obtain a mixed system;

[0017] S33: Add bisphenol A epoxy resin and bisphenol F epoxy resin to the mixed system, keep stirring, and the stirring time is 20 - 30 min; add 0.5 - 2 wt% of azobisisobutyronitrile to the mixed system, and stir at 300 - 500 rpm for 1 - 3 h to obtain the glue solution.

[0018] Preferably, in the step 2, add modified nano-alumina / carbon nanotube composite powder to the twin-screw extruder. The modified nano-alumina / carbon nanotube composite powder accounts for 2% - 5% of the mass of the polyethylene powder. The preparation method of the modified nano-alumina / carbon nanotube composite powder includes:

[0019] S1. Disperse carbon nanotubes with a diameter of 10 - 20 nm in a 1 - 2 mol / L sodium hydroxide solution, heat up to 60 - 80 °C, keep warm for 1 - 3 h, cool and filter, then wash the carbon nanotubes with deionized water until neutral to obtain alkalized carbon nanotubes; disperse the alkalized carbon nanotubes in absolute ethanol, add KH550 silane coupling agent, and perform ultrasonic treatment at 60 °C for 2 - 4 h with an ultrasonic frequency of 40 kHz to obtain a carbon nanotube dispersion;

[0020] S2. Add aluminum isopropoxide and 0.1 M ammonia water solution to the carbon nanotube dispersion, perform ultrasonic dispersion at 60 °C with a frequency of 40 - 55 kHz for 1 - 2 h to obtain a reaction system; dropwise add deionized water to the reaction system, and perform constant-temperature stirring at 70 - 90 °C for 4 - 8 h to form an AlOOH-CNTs composite sol;

[0021] S3. Freeze-dry the AlOOH-CNTs composite sol and then perform three-stage calcination to obtain a modified nano-aluminum oxide / carbon nanotube composite powder.

[0022] Preferably, in S1, the dosage ratio of carbon nanotubes to sodium hydroxide solution is 1 - 5 g:250 mL; the dosage ratio of alkalized carbon nanotubes, absolute ethanol, and KH550 silane coupling agent is 1 - 5 g:200 - 500 mL:0.1 - 2 g; in S2, the dosage ratio of alkalized carbon nanotubes, aluminum isopropoxide, ammonia water solution, and deionized water is 1 - 5 g:20 - 60 g:10 - 20 mL:7 - 25 mL.

[0023] Preferably, in S3, the three-stage calcination specifically includes: heating up to 300 - 500 °C at a rate of 5 °C / min, keeping warm for 1 h; then heating up to 600 - 700 °C at a rate of 10 °C / min, keeping warm for 2 h; finally heating up to 800 - 900 °C at a rate of 20 °C / min, keeping warm for 20 - 30 min, and cooling to room temperature to obtain a modified nano-aluminum oxide / carbon nanotube composite powder.

[0024] The present invention has at least the following beneficial effects: A preparation method of ultra-high molecular weight polyethylene fibers provided by the present invention involves adding a spinning dope and a modified nano-alumina / carbon nanotube composite powder into a twin-screw extruder for twin-screw extrusion, and after spinning through a spinneret, immersing the fiber filaments in an impregnating bath filled with sizing solution for a certain period of time to prepare ultra-high molecular weight polyethylene fibers with high strength and excellent wear resistance; among them, the modified nano-alumina / carbon nanotube composite powder is prepared by a sol-gel method, using nano-alumina to coat alkaline carbon nanotubes, and finally through three-stage gradient calcination to obtain the modified nano-alumina / carbon nanotube composite powder; heating at a rate of 5 °C / min to 300 - 500 °C to remove residual solvents, heating at a rate of 10 °C / min to 600 - 700 °C to form C-O-Al bonding between nano-alumina and carbon nanotubes, and heating at a rate of 20 °C / min to 800 - 900 °C to enhance the tightness of the combination of nano-alumina powder and carbon nanotubes and enhance the interfacial stress matching of the two materials.

[0025] The sizing solution disclosed in the present invention uses isooctyl acrylate and polyurethane as main raw materials, 1,6-hexanediol diacrylate as an initiator. Isooctyl acrylate and polyurethane crosslink to form a viscous three-dimensional network, improving the hardness of the sizing layer formed by the sizing solution. After adding bisphenol A epoxy resin and bisphenol F epoxy resin, the sizing solution has anti-aging properties, reducing the crack propagation path of the surface coating of polyethylene fibers; after the polyethylene fibers are immersed in the sizing solution, an elastic wear-resistant layer is formed on their surface, significantly improving the wear resistance of the polyethylene fibers.

[0026] Other advantages, objectives, and features of the present invention will be partially reflected by the following description and partially understood by those skilled in the art through the research and practice of the present invention. Detailed Embodiments

[0027] The following provides a further detailed description of the present invention so that those skilled in the art can implement it with reference to the text of the specification.

[0028] It should be understood that terms such as "having", "comprising", and "including" used herein do not exclude the presence or addition of one or more other elements or their combinations.

[0029] Example 1

[0030] This example provides a preparation method of ultra-high molecular weight polyethylene fibers, including the following steps:

[0031] Step 1: Add 1000 g of ultra-high molecular weight polyethylene powder with a weight average molecular weight of 5 million into 5000 g of decalin to dissolve and obtain a spinning dope;

[0032] Step 2: Add the spinning dope into a twin-screw extruder and extrude at 130°C to obtain a gel-like spinning solution;

[0033] Step 3: Filter the spinning solution, extrude it through a spinneret with a spinneret diameter of 0.05 mm to obtain fiber filaments, and extract the fiber filaments. Wash them repeatedly with clear water, dry at 60°C, stretch by 120% at 150°C, and then perform heat setting at 160°C to obtain fiber filaments. Immerse the fiber filaments in an impregnating bath filled with sizing solution for 3 hours, wash and dry to obtain ultra-high molecular weight polyethylene fibers.

[0034] Among them, the preparation method of the sizing solution includes:

[0035] S31: Pour 200 g of isooctyl acrylate into a container and rotate it at a speed of 200 rpm to make the isooctyl acrylate in a uniform flowing state; slowly add 200 g of polyurethane to the isooctyl acrylate and continue stirring to fully disperse and dissolve the polyurethane in the isooctyl acrylate. The stirring time is 30 min to obtain a mixed solution;

[0036] S32: Add 10 g of 1,6-hexanediol diacrylate to the mixed solution, increase the stirring speed to 300 rpm, and stir for 30 min to fully mix 1,6-hexanediol diacrylate with isooctyl acrylate and polyurethane to obtain a mixed system;

[0037] S33: Add 50 g of bisphenol A epoxy resin and 50 g of bisphenol F epoxy resin to the mixed system, keep stirring to evenly disperse the bisphenol A epoxy resin and bisphenol F epoxy resin in the mixed system, and the stirring time is 30 min; add 3 g of azobisisobutyronitrile to the mixed system and stir at 300 rpm for 3 h to obtain the sizing solution.

[0038] Example 2

[0039] This example provides a method for preparing ultra-high molecular weight polyethylene fibers, including the following steps:

[0040] Step 1: Add 1000 g of ultra-high molecular weight polyethylene powder with a weight average molecular weight of 5 million into 5000 g of decalin and dissolve to obtain a spinning dope;

[0041] Step 2: Add the spinning dope into a twin-screw extruder and extrude at 130°C to obtain a gel-like spinning solution;

[0042] Step 3: Filter the spinning solution, extrude it through a spinneret to obtain fiber filaments. The spinneret has a spinning diameter of 0.05 mm. Extract the fiber filaments, wash them repeatedly with clear water, dry them at 60°C, stretch them by 120% at 150°C, and then perform heat setting at 160°C to obtain fiber filaments. Immerse the fiber filaments in an impregnating tank filled with sizing solution for 3 hours, wash and dry them to obtain ultra-high molecular weight polyethylene fibers.

[0043] Among them, the preparation method of the sizing solution includes:

[0044] S31: Pour 300 g of isooctyl acrylate into a container and keep it in a uniformly flowing state at a rotation speed of 200 rpm. Slowly add 150 g of polyurethane to the isooctyl acrylate, continue stirring to fully disperse and dissolve the polyurethane in the isooctyl acrylate, and stir for 30 minutes to obtain a mixed solution.

[0045] S32: Add 20 g of 1,6-hexanediol diacrylate to the mixed solution, increase the stirring speed to 300 rpm, and stir for 30 minutes to fully mix 1,6-hexanediol diacrylate with isooctyl acrylate and polyurethane to obtain a mixed system.

[0046] S33: Add 80 g of bisphenol A epoxy resin and 20 g of bisphenol F epoxy resin to the mixed system, keep stirring to evenly disperse the bisphenol A epoxy resin and bisphenol F epoxy resin in the mixed system, and stir for 30 minutes. Add 5 g of azobisisobutyronitrile to the mixed system and stir at 300 rpm for 3 hours to obtain the sizing solution.

[0047] Example 3

[0048] This example provides a method for preparing ultra-high molecular weight polyethylene fibers, including the following steps:

[0049] Step 1: Add 1000 g of ultra-high molecular weight polyethylene powder with a weight average molecular weight of 5 million to 5000 g of decahydronaphthalene and dissolve it to obtain a spinning dope.

[0050] Step 2: Add the spinning dope to a twin-screw extruder and extrude it at 130°C to obtain a gel-like spinning solution.

[0051] Step 3: Filter the spinning solution, extrude it through a spinneret to obtain fiber filaments. The spinneret has a spinning diameter of 0.05 mm. Extract the fiber filaments, wash them repeatedly with clear water, dry them at 60°C, stretch them by 120% at 150°C, and then perform heat setting at 160°C to obtain fiber filaments. Immerse the fiber filaments in an impregnating tank filled with sizing solution for 3 hours, wash and dry them to obtain ultra-high molecular weight polyethylene fibers.

[0052] Among them, the preparation method of the sizing solution includes:

[0053] S31. Pour 400 g of isooctyl acrylate into a container and rotate it at a speed of 200 rpm to keep the isooctyl acrylate in a uniform flowing state. Slowly add 50 g of polyurethane to the isooctyl acrylate and continue stirring to fully disperse and dissolve the polyurethane in the isooctyl acrylate. The stirring time is 30 min to obtain a mixed solution.

[0054] S32. Add 10 g of 1,6 - hexanediol diacrylate to the mixed solution, increase the stirring speed to 300 rpm, and stir for 30 min to fully mix 1,6 - hexanediol diacrylate with isooctyl acrylate and polyurethane to obtain a mixed system.

[0055] S33. Add 100 g of bisphenol A epoxy resin and 10 g of bisphenol F epoxy resin to the mixed system, keep stirring to evenly disperse the bisphenol A epoxy resin and bisphenol F epoxy resin in the mixed system, and the stirring time is 30 min. Add 6 g of azobisisobutyronitrile to the mixed system and stir at 300 rpm for 3 h to obtain a glue solution.

[0056] Example 4

[0057] This example provides a preparation method of ultra - high molecular weight polyethylene fiber. The difference from Example 1 is that in step two, 30 g of modified nano - alumina / carbon nanotube composite powder is added to the twin - screw extruder for co - blending and extrusion with the spinning solution. The methods and process parameters of the remaining steps in this example are the same as those in Example 1. Among them, the preparation method of the modified nano - alumina / carbon nanotube composite powder includes:

[0058] S1. Disperse 5 g of carbon nanotubes with a diameter of 10 - 20 nm in 250 mL of a sodium hydroxide solution with a concentration of 1 mol / L, raise the temperature to 80 °C, keep it warm for 3 h, cool and filter, and then wash the carbon nanotubes with deionized water until neutral to obtain alkalized carbon nanotubes. Disperse 5 g of alkalized carbon nanotubes in 250 ml of absolute ethanol, add 0.5 g of KH550 silane coupling agent, and perform ultrasonic treatment at a temperature of 60 °C for 2 h with an ultrasonic frequency of 40 kHz to obtain a carbon nanotube dispersion.

[0059] S2. Add 20 g of aluminum isopropoxide and 10 mL of an ammonia water solution with a concentration of 0.1 M to the carbon nanotube dispersion, perform ultrasonic dispersion at a temperature of 60 °C and a frequency of 40 kHz for 2 h to obtain a reaction system. Drop 7.5 mL of deionized water into the reaction system and stir at a constant temperature of 80 °C for 4 h to form an AlOOH - CNTs composite sol.

[0060] After the AlOOH-CNTs composite sol is freeze-dried at -25°C for 3 h, it is heated to 300°C at a rate of 5°C / min and held for 1 h; then it is heated to 600°C at a rate of 10°C / min and held for 2 h; finally, it is heated to 900°C at a rate of 20°C / min and held for 30 min, and then cooled to room temperature to obtain the modified nano-aluminum oxide / carbon nanotube composite powder.

[0061] Example 5

[0062] This example provides a method for preparing ultra-high molecular weight polyethylene fibers. Different from Example 1, in step two of this example, 40 g of the modified nano-aluminum oxide / carbon nanotube composite powder is added to the twin-screw extruder and co-extruded with the spinning solution. The methods and process parameters of the remaining steps in this example are the same as those in Example 1; the preparation method of the modified nano-aluminum oxide / carbon nanotube composite powder includes:

[0063] S1. Disperse 5 g of carbon nanotubes with a diameter of 10 - 20 nm in 250 mL of sodium hydroxide solution with a concentration of 2 mol / L, heat to 60°C, hold for 3 h, cool and filter, and then wash the carbon nanotubes with deionized water until neutral to obtain alkalized carbon nanotubes; Disperse 5 g of alkalized carbon nanotubes in 250 mL of absolute ethanol, add 1.5 g of KH550 silane coupling agent, and perform ultrasonic treatment at 60°C for 4 h with an ultrasonic frequency of 40 kHz to obtain a carbon nanotube dispersion;

[0064] S2. Add 40 g of aluminum isopropoxide and 15 mL of ammonia water with a concentration of 0.1 M to the carbon nanotube dispersion, and perform ultrasonic dispersion at 60°C and 40 kHz for 1 h to obtain a reaction system; Drop 15 mL of deionized water into the reaction system, and stir at a constant temperature of 80°C for 5 h to form an AlOOH-CNTs composite sol;

[0065] S3. After the AlOOH-CNTs composite sol is freeze-dried at -25°C for 3 h, it is heated to 300°C at a rate of 5°C / min and held for 1 h; then it is heated to 600°C at a rate of 10°C / min and held for 2 h; finally, it is heated to 900°C at a rate of 20°C / min and held for 30 min, and then cooled to room temperature to obtain the modified nano-aluminum oxide / carbon nanotube composite powder.

[0066] Example 6

[0067] This example provides a method for preparing ultra-high molecular weight polyethylene fibers. Different from Example 1, in step two of this example, 30 g of the modified nano-aluminum oxide / carbon nanotube composite powder is added to the twin-screw extruder and co-extruded with the spinning solution. The methods and process parameters of the remaining steps in this example are the same as those in Example 1;

[0068] S1. Disperse 5 g of carbon nanotubes with a diameter of 10 - 20 nm in 250 mL of sodium hydroxide solution with a concentration of 2 mol / L, heat up to 80 °C, keep warm for 3 h, cool and filter, then wash the carbon nanotubes with deionized water until neutral to obtain alkalized carbon nanotubes; Disperse 5 g of alkalized carbon nanotubes in 250 mL of absolute ethanol, add 2 g of KH550 silane coupling agent, and perform ultrasonic treatment at 60 °C for 4 h with an ultrasonic frequency of 40 kHz to obtain a carbon nanotube dispersion;

[0069] S2. Add 60 g of aluminum isopropoxide and 20 mL of ammonia water solution with a concentration of 0.1 M to the carbon nanotube dispersion, perform ultrasonic dispersion at 60 °C and 40 kHz for 2 h to obtain a reaction system; Dropwise add 22.5 mL of deionized water to the reaction system, and stir at a constant temperature of 90 °C for 6 h to form an AlOOH-CNTs composite sol;

[0070] S3. After freeze-drying the AlOOH-CNTs composite sol at -25 °C for 3 h, heat it up to 300 °C at a rate of 5 °C / min and keep warm for 1 h; Then heat it up to 600 °C at a rate of 10 °C / min and keep warm for 2 h; Finally, heat it up to 900 °C at a rate of 20 °C / min and keep warm for 30 min, and cool it to room temperature to obtain a modified nano-aluminum oxide / carbon nanotube composite powder.

[0071] Comparative Example 1

[0072] This comparative example provides a preparation method of ultra-high molecular weight polyethylene fiber. Different from Example 1, in step three of this comparative example, after heat-setting to obtain fiber filaments, the fiber filaments are not immersed in an impregnating bath filled with sizing solution, and the heat-set fiber filaments are directly cooled to obtain polyethylene fibers. The methods and process parameters of the remaining steps in this comparative example are the same as those in Example 1.

[0073] Comparative Example 2

[0074] This comparative example provides a preparation method of ultra-high molecular weight polyethylene fiber. Compared with Example 1, in step two of this comparative example, 10 g of carbon nanotubes with a diameter of 10 - 20 nm and 20 g of nano-aluminum oxide powder are added to a twin-screw extruder and blended and extruded with a spinning solution. The methods and process parameters of the remaining steps in this comparative example are the same as those in Example 1. Among them, the preparation method of nano-aluminum oxide in this comparative example includes:

[0075] S1. Add 20 g of aluminum isopropoxide and 10 mL of ammonia water solution with a concentration of 0.1 M to 250 mL of absolute ethanol, perform ultrasonic dispersion at 60 °C and 40 kHz for 2 h to obtain a reaction system; Dropwise add 7.5 mL of deionized water to the reaction system, and stir at a constant temperature of 80 °C for 4 h to form a sol;

[0076] S2. After freeze-drying the sol at -25°C for 3 h, heat it to 300°C at a rate of 5°C / min and hold for 1 h; then heat it to 600°C at a rate of 10°C / min and hold for 2 h; finally, heat it to 900°C at a rate of 20°C / min, hold for 30 min, and cool to room temperature to obtain nano-aluminum oxide powder.

[0077] Comparative Example 3

[0078] This comparative example provides a method for preparing ultra-high molecular weight polyethylene fiber. Compared with Example 1, in Step 2 of this comparative example, 30 g of carbon nanotubes with a diameter of 10 - 20 nm are added to the twin-screw extruder and co-mixed and extruded with the spinning solution. The methods and process parameters of the remaining steps in this comparative example are the same as those in Example 1.

[0079] Comparative Example 4

[0080] This comparative example provides a method for preparing ultra-high molecular weight polyethylene fiber. Compared with Example 1, in Step 2 of this comparative example, 30 g of nano-aluminum oxide powder is added to the twin-screw extruder and co-mixed and extruded with the spinning solution. The methods and process parameters of the remaining steps in this comparative example are the same as those in Example 1. Among them, the preparation method of the nano-aluminum oxide in this comparative example includes:

[0081] S1. Add 20 g of aluminum isopropoxide and 10 mL of ammonia water solution with a concentration of 0.1 M to 250 mL of absolute ethanol, and ultrasonically disperse at 40 kHz for 2 h at 60°C to obtain a reaction system; add 7.5 mL of deionized water dropwise to the reaction system and stir at a constant temperature of 80°C for 4 h to form a sol.

[0082] S2. After freeze-drying the sol at -25°C for 3 h, heat it to 300°C at a rate of 5°C / min and hold for 1 h; then heat it to 600°C at a rate of 10°C / min and hold for 2 h; finally, heat it to 900°C at a rate of 20°C / min, hold for 30 min, and cool to room temperature to obtain nano-aluminum oxide powder.

[0083] Measure the wear resistance, breaking strength, elongation at break, and elastic modulus of the polyethylene fibers prepared in Examples 1 - 6 and Comparative Examples 1 - 4 respectively to obtain Table 1; among them, the wear resistance test refers to FZ / T 50025-2014 "Test Method for Wear Resistance of Ultra-High Molecular Weight Polyethylene Filaments" and JISL1095-2010 "Test Methods for General Yarns"; the measurement methods of breaking strength, elongation at break, and elastic modulus refer to GB / T19975-2005 "Test Method for Tensile Properties of High-Strength Chemical Fibre Filaments", and use an INSTRON 34SC-2 type electronic tensile machine for testing.

[0084] Table 1 Test Results of Performance Data of Polyethylene Fibers in Each Example and Comparative Example

[0085]

[0086]

[0087] As can be seen from the above table, the high-strength wear-resistant polyethylene fibers prepared in Examples 4-6 have more wear-resistant times, greater breaking strength, breaking elongation and elastic modulus, indicating that after impregnating the fiber filaments with glue and incorporating the modified nano-alumina / carbon nanotube composite powder into the spinning solution, the wear resistance and strength of the ultra-high molecular weight polyethylene fibers prepared are significantly improved.

[0088] The equipment quantities and processing scales described here are used to simplify the description of the present invention. Applications, modifications and variations of the present invention will be apparent to those skilled in the art.

[0089] Although the embodiments of the present invention have been disclosed as above, they are not limited to only the applications listed in the specification and embodiments. It can be fully applied to various fields suitable for the present invention. For those familiar with the field, additional modifications can be easily achieved. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details and the examples shown and described here.

Claims

1. A preparation method of ultra-high molecular weight polyethylene fiber, characterized in that, It includes the following steps: Step 1: Add ultra-high molecular weight polyethylene powder into a solvent and dissolve it to obtain a spinning dope. Step 2: Add the spinning dope into a twin-screw extruder and co-extrude to obtain a spinning solution. Step 3: Filter the spinning solution, extrude it through a spinneret to obtain fiber filaments, extract the fiber filaments, wash, dry, stretch, heat-set them, immerse them in a sizing solution, take them out, wash and dry to obtain ultra-high molecular weight polyethylene fibers.

2. The preparation method of the ultra-high molecular weight polyethylene fiber according to claim 1, wherein In the said Step 1, the weight-average molecular weight of the ultra-high molecular weight polyethylene powder is 3 million to 10 million.

3. The preparation method of ultra-high molecular weight polyethylene fiber according to claim 1, wherein In the said Step 1, the solvent is decalin, white oil or paraffin oil, and the mass percentage of the polyethylene powder in the solvent is 10% to 20%.

4. The preparation method of ultra-high molecular weight polyethylene fiber according to claim 1, characterized in that, In the said Step 2, the extrusion temperature of the twin-screw extruder is 130 to 180 °C.

5. The preparation method of the ultra-high molecular weight polyethylene fiber according to claim 1, characterized in that, In the said Step 3, the spinneret hole diameter of the spinneret is 0.05 to 0.5 mm.

6. The preparation method of the ultra-high molecular weight polyethylene fiber according to claim 1, characterized in that, In the said Step 3, the sizing solution includes by weight: 20 to 40 parts of isooctyl acrylate, 5 to 20 parts of polyurethane, 1 to 5 parts of 1,6-hexanediol diacrylate, 5 to 10 parts of bisphenol A epoxy resin, 1 to 5 parts of bisphenol F epoxy resin.

7. The preparation method of the ultra-high molecular weight polyethylene fiber according to claim 6, characterized in that, The preparation method of the said sizing solution includes: S31: Pour isooctyl acrylate into a container, and at a rotation speed of 100 to 200 rpm, make the isooctyl acrylate in a uniform flowing state; slowly add polyurethane to the isooctyl acrylate, continue stirring to make the polyurethane fully dispersed and dissolved in the isooctyl acrylate, and the stirring time is 15 to 30 min to obtain a mixed solution. S32: Add 1,6-hexanediol diacrylate to the mixed solution, increase the stirring speed to 300 to 500 rpm, and stir for 10 to 30 min to obtain a mixed system. S33: Add bisphenol A epoxy resin and bisphenol F epoxy resin to the mixed system, keep stirring, and the stirring time is 20 to 30 min; add 0.5 to 2 wt% of azobisisobutyronitrile to the mixed system, and stir at 300 to 500 rpm for 1 to 3 h to obtain the sizing solution.

8. The preparation method of the ultra-high molecular weight polyethylene fiber according to claim 1, characterized in that, In the said Step 2, add a modified nano-alumina / carbon nanotube composite powder to the twin-screw extruder. The modified nano-alumina / carbon nanotube composite powder accounts for 2 to 5% of the mass of the polyethylene powder. The preparation method of the modified nano-alumina / carbon nanotube composite powder includes: S1: Disperse carbon nanotubes with a diameter of 10 to 20 nm in a 1 to 2 mol / L sodium hydroxide solution, raise the temperature to 60 to 80 °C, keep warm for 1 to 3 h, cool and filter, and wash the carbon nanotubes with deionized water until neutral to obtain alkalized carbon nanotubes; disperse the alkalized carbon nanotubes in anhydrous ethanol, add KH550 silane coupling agent, and perform ultrasonic treatment at 60 °C for 2 to 4 h, and the ultrasonic frequency is 40 kHz to obtain a carbon nanotube dispersion. S2: Add aluminum isopropoxide and 0.1 M ammonia water solution to the carbon nanotube dispersion, perform ultrasonic dispersion at 60 °C at 40 to 55 kHz for 1 to 2 h to obtain a reaction system; dropwise add deionized water to the reaction system, and keep stirring at 70 to 90 °C for 4 to 8 h to form an AlOOH-CNTs composite sol. In S3, the AlOOH-CNTs composite sol is freeze-dried and then subjected to three-stage calcination to obtain the modified nano-alumina / carbon nanotube composite powder.

9. The preparation method of the ultra-high molecular weight polyethylene fiber according to claim 8, wherein In the said S1, the dosage ratio of carbon nanotubes to sodium hydroxide solution is 1-5 g:250 mL; the dosage ratio of alkalized carbon nanotubes, absolute ethanol, and KH550 silane coupling agent is 1-5 g:200-500 mL:0.1-2 g; in the said S2, the dosage ratio of alkalized carbon nanotubes, aluminum isopropoxide, ammonia water solution, and deionized water is 1-5 g:20-60 g:10-20 mL:7-25 mL.

10. The preparation method of the ultra-high molecular weight polyethylene fiber according to claim 8, characterized in that, In the said S3, the three-stage calcination specifically includes: heating at a rate of 5 °C / min to 300-500 °C and holding for 1 h; then heating at a rate of 10 °C / min to 600-700 °C and holding for 2 h; finally heating at a rate of 20 °C / min to 800-900 °C and holding for 20-30 min, and cooling to room temperature to obtain the modified nano-alumina / carbon nanotube composite powder.

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