High-strength ultra-high molecular weight polyethylene melt spinning fiber and preparation method thereof

Abstract

The invention provides a high-strength ultra-high molecular weight polyethylene melt spinning fiber and a preparation method thereof, and relates to the technical field of high polymer materials. The preparation method comprises the following steps: firstly, preparing modified acidified multi-walled carbon nanotubes and modified montmorillonite, then mixing the modified acidified multi-walled carbon nanotubes and the modified montmorillonite as auxiliaries with ultrahigh molecular weight polyethylene, high-density polyethylene and an antioxidant in proportion, and carrying out melt spinning to obtain the high-strength ultrahigh molecular weight polyethylene melt spinning fiber. Through the synergistic effect of the modified acidified multi-walled carbon nanotubes and the modified montmorillonite, the entanglement phenomenon of ultra-high molecular weight polyethylene macromolecular chains is remarkably reduced, and the orientation and stretching effects of the molecular chains are enhanced, so that the tensile strength of the fiber is effectively improved. The preparation method provided by the invention is relatively simple and convenient to operate, the final performance of the fiber can be flexibly regulated and controlled by adjusting the proportion of the components, the reaction temperature and the reaction time, and the preparation method has good controllability and adaptability, is suitable for industrial production and has a good industrial application prospect.

Description

Technical Field

[0001] The invention relates to the technical field of polymer materials, and in particular to a high-strength ultra-high molecular weight polyethylene melt-spun fiber and a preparation method thereof. Background Art

[0002] Ultra-high molecular weight polyethylene fiber (UHMWPE fiber) is a high-performance polymer fiber material with a series of excellent properties due to its extremely high molecular weight (usually between 3 million and 6 million g / mol). UHMWPE fiber has extremely high tensile strength, usually between 2.4-4.8GPa, and its specific strength far exceeds that of steel and many traditional fiber materials. At the same time, its density is extremely low, about 0.93-0.97g / cm 3 , making it extremely competitive in applications that require lightweight materials. In addition, UHMWPE fiber also has excellent wear resistance and is one of the best wear-resistant materials among all commercial fibers. It has excellent tolerance to most chemicals, acids, alkalis and organic solvents, and can maintain high strength and toughness in extremely low temperature environments, making it particularly suitable for applications under low temperature conditions. The low water absorption of UHMWPE fiber enables it to maintain stable performance in humid environments, and its UV resistance is relatively good, and it is not easily degraded by light. Due to its molecular structure and extremely low surface energy, UHMWPE fiber is difficult to dye by traditional dyeing methods, and usually requires a special surface treatment process. UHMWPE fiber is widely used in bulletproof vests, bulletproof helmets, armor, high-strength ropes and cables in the marine and aerospace fields, composite reinforcements, cut-resistant gloves and protective clothing. In addition, the fiber is also used in high-performance sports equipment, such as skis and fishing lines, to improve the performance and durability of the product. Due to its light weight, high strength, excellent wear resistance, chemical resistance and low temperature resistance, UHMWPE fiber has great application prospects in industries that require high-performance materials, such as industry, military and sports.

[0003] At present, high-performance fibers and membrane materials are generally prepared by melt spinning and gel spinning. The melt spinning method is to heat the polymer to above its melting point to melt it into a fluid state, then extrude it through a spinneret to form filaments, and finally solidify it by cooling to form fibers. The gel spinning method is to dissolve the polymer in an appropriate solvent to form a gel state, then extrude it through a spinneret, and then form it into fibers by removing the solvent or using a coagulant. However, due to the high molecular weight, high melt viscosity, molecular chain entanglement and insufficient orientation of ultra-high molecular weight polyethylene, it is difficult to achieve effective stretching and stretching during the melt spinning process, resulting in a low tensile strength of the final prepared fiber. This also leads to the fact that UHMWPE fibers are more often prepared by gel spinning. However, compared with the melt spinning method, the gel spinning method has problems such as complex process, high cost, low efficiency, poor environmental protection, and unsuitability for large-scale industrial production.

[0004] Therefore, the existing technology is currently unable to directly use the melt spinning method to prepare UHMWPE fibers. Summary of the invention

[0005] In view of this, the object of the present invention is to provide a high-strength ultra-high molecular weight polyethylene melt-spun fiber and a preparation method thereof. The preparation method provided by the present invention utilizes the synergistic effect between modified acidified multi-walled carbon nanotubes and modified montmorillonite, so that the ultra-high molecular weight polyethylene macromolecular chains produce effects such as orientation and stretching during the molding process, thereby greatly reducing molecular entanglement and ultimately improving the tensile strength of the fiber, thereby obtaining a high-strength ultra-high molecular weight polyethylene melt-spun fiber.

[0006] The present invention provides a method for preparing high-strength ultra-high molecular weight polyethylene melt-spun fibers, comprising the following steps:

[0007] S1, adding multi-walled carbon nanotubes to a hydrochloric acid solution and stirring evenly, adding γ-(methacryloyloxy)propyltrimethoxysilane and heating, stirring and reacting to obtain modified acidified multi-walled carbon nanotubes;

[0008] S2, evenly dispersing sodium montmorillonite in deionized water, adjusting the pH to 6-7, adding octadecyltrimethylammonium chloride and stirring for reaction, filtering after the reaction is completed, drying, and ball milling to obtain modified montmorillonite;

[0009] S3, mixing the ultra-high molecular weight polyethylene, high-density polyethylene, the modified acidified multi-walled carbon nanotubes obtained in step S1, the modified montmorillonite obtained in step S2, and an antioxidant uniformly, and then putting them into a twin-screw extruder for melt spinning and cooling in a water bath to obtain high-strength ultra-high molecular weight polyethylene melt-spun fibers.

[0010] Furthermore, in S1, the concentration of the hydrochloric acid solution is 30% to 40%, and the mass ratio of the multi-walled carbon nanotubes to the hydrochloric acid solution is 1:(2 to 3).

[0011] Furthermore, in S1, the mass ratio of multi-walled carbon nanotubes to γ-(methacryloyloxy)propyltrimethoxysilane is 1:(0.5-1).

[0012] Furthermore, in S1, the reaction temperature is 25°C to 35°C, and the reaction time is 1 to 3 hours.

[0013] Further, in S2, the mass ratio of the sodium montmorillonite to octadecyltrimethylammonium chloride is 1:(0.2-0.4). Preferably, in S2, the mass ratio of the sodium montmorillonite to octadecyltrimethylammonium chloride is 1:0.3.

[0014] Furthermore, in S2, the reaction temperature is room temperature and the reaction time is 0.5 to 1 h.

[0015] Furthermore, in S2, the drying temperature is 60° C. to 80° C., and the drying time is 12 to 24 hours.

[0016] Furthermore, the particle size of the modified montmorillonite is ≤50 μm.

[0017] Furthermore, in S3, the viscosity average molecular weight of the ultra-high molecular weight polyethylene is 1 million to 2.4 million, and the viscosity average molecular weight of the high density polyethylene is 200,000 to 500,000.

[0018] Further, in said S3, the mass ratio of ultra-high molecular weight polyethylene to high-density polyethylene is 1:(0.2-0.8). Preferably, in said S3, the mass ratio of ultra-high molecular weight polyethylene to high-density polyethylene is 1:0.5.

[0019] Further, in said S3, the amount of modified acidified multi-walled carbon nanotubes added is 1.5% to 5% of the ultra-high molecular weight polyethylene, the amount of modified montmorillonite added is 1.5% to 5% of the ultra-high molecular weight polyethylene, and the amount of antioxidant added is 0.5% to 2% of the ultra-high molecular weight polyethylene. Preferably, in said S3, the amount of modified acidified multi-walled carbon nanotubes added is 3.5% of the ultra-high molecular weight polyethylene, the amount of modified montmorillonite added is 2.5% of the ultra-high molecular weight polyethylene, and the amount of antioxidant added is 1.25% of the ultra-high molecular weight polyethylene.

[0020] The present invention also provides a high-strength ultra-high molecular weight polyethylene melt-spun fiber prepared according to the method.

[0021] Compared with the prior art, the beneficial technical effects of the present invention are:

[0022] The present invention significantly reduces the entanglement of ultra-high molecular weight polyethylene macromolecular chains through the synergistic effect of modified acidified multi-walled carbon nanotubes and modified montmorillonite, enhances the orientation and stretching effect of the molecular chains, and thus effectively improves the tensile strength of the fiber.

[0023] The present invention ensures uniform dispersion and full combination of the modified material and the ultra-high molecular weight polyethylene matrix by reasonably optimizing the modification reaction conditions and proportions of the carbon nanotubes and montmorillonite, thereby improving the overall performance of the fiber.

[0024] The preparation method provided by the present invention is relatively simple to operate, and the final properties of the fiber can be flexibly controlled by adjusting the proportion of each component, reaction temperature and time. It has good controllability and adaptability, is suitable for industrial production, and has good industrial application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present invention will be further described below in conjunction with the accompanying drawings.

[0026] Figure 1 The present invention is a process flow chart for preparing high-strength ultra-high molecular weight polyethylene melt-spun fibers. DETAILED DESCRIPTION

[0027] The present invention provides a high-strength ultra-high molecular weight polyethylene melt-spun fiber and a preparation method thereof. Those skilled in the art can refer to the content of this article and appropriately improve the process parameters to achieve it. It should be particularly noted that all similar substitutions and modifications are obvious to those skilled in the art, and they all fall within the scope of protection of the present invention. The method and application of the present invention have been described through preferred embodiments, and relevant personnel can obviously modify or appropriately change and combine the method and application of this article without departing from the content, spirit and scope of the present invention to implement and apply the technology of the present invention.

[0028] It should be understood that in the various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean the order of execution, and some or all of them can be executed in parallel or one after the other. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0029] The numerical ranges and parameters involved in the present invention have presented the relevant numerical values ​​in the specific embodiments as accurately as possible. However, any numerical value essentially inevitably contains standard deviations due to individual testing methods. Therefore, unless otherwise explicitly stated, it should be understood that all numerical ranges or specific data used in this disclosure may have certain reasonable deviations within a certain range, for example: within 1% or 0.5%.

[0030] Some cases are recorded in the embodiments and comparative examples of the present invention, wherein the embodiments show certain implementation modes of the present invention. However, this does not mean that the effects of the present invention can only be achieved in these cases.

[0031] In order to further illustrate the present invention, a high-strength ultra-high molecular weight polyethylene melt-spun fiber and a preparation method thereof provided by the present invention are described in detail below in conjunction with embodiments.

[0032] Unless otherwise specified, all experiments were repeated three times. SPSS 21.0 was used for analysis of variance (ANOVA) and Duncan's multiple comparison analysis, and the results were expressed as mean ± SD.

[0033] The viscosity average molecular weight of the ultra-high molecular weight polyethylene used in the specific embodiment of the present invention is 2.4 million, and the viscosity average molecular weight of the high density polyethylene is 200,000.

[0034] Example 1 The preparation method of the high-strength ultra-high molecular weight polyethylene melt-spun fiber of the present invention comprises the following steps:

[0035] Add multi-walled carbon nanotubes to a 35% hydrochloric acid solution at a mass ratio of 1:2.5 and stir evenly, add γ-(methacryloyloxy)propyltrimethoxysilane at a mass ratio of 1:0.8 to multi-walled carbon nanotubes and γ-(methacryloyloxy)propyltrimethoxysilane, then heat to 30°C, stir and react for 2 hours to obtain modified acidified multi-walled carbon nanotubes; disperse sodium montmorillonite evenly in deionized water, adjust the pH to 7, add octadecyltrimethylammonium chloride at a mass ratio of 1:0.3 to sodium montmorillonite and octadecyltrimethylammonium chloride, stir and react at room temperature for 0.5 hours, filter after the reaction is completed, dry at 60°C for 18 hours, and ball mill to obtain modified montmorillonite with a particle size of ≤50μm; Ultra-high molecular weight polyethylene, high-density polyethylene, modified acidified multi-walled carbon nanotubes, modified montmorillonite and antioxidant 1010 are mixed evenly and put into a twin-screw extruder, wherein the mass ratio of ultra-high molecular weight polyethylene to high-density polyethylene is 1:0.5, the addition amount of modified acidified multi-walled carbon nanotubes is 3.5% of the ultra-high molecular weight polyethylene, the addition amount of modified montmorillonite is 2.5% of the ultra-high molecular weight polyethylene, and the addition amount of antioxidant 1010 is 1.25% of the ultra-high molecular weight polyethylene. Melt spinning (the temperature range of the five zones of the screw during the melt spinning process is 270°C, 300°C, 310°C, 320°C, 320°C), and cooling in a 40°C water bath to obtain high-strength ultra-high molecular weight polyethylene melt-spun fibers.

[0036] The high-strength ultra-high molecular weight polyethylene melt-spun fibers prepared in this embodiment have a smooth surface and are uniform. After testing, the fiber fineness is (1637±25) dtex and the strength is (32.65±1.02) cN / dtex.

[0037] Comparative Example 1 A method for preparing ultra-high molecular weight polyethylene fiber, comprising the following steps:

[0038] The multi-walled carbon nanotubes were added to a 35% hydrochloric acid solution at a mass ratio of 1:2.5 and stirred evenly. γ-(methacryloyloxy)propyltrimethoxysilane was added at a mass ratio of 1:0.8 to the multi-walled carbon nanotubes and γ-(methacryloyloxy)propyltrimethoxysilane, and the temperature was raised to 30°C. After stirring for 2 hours, modified acidified multi-walled carbon nanotubes were obtained. Ultra-high molecular weight polyethylene, high-density polyethylene, modified acidified multi-walled carbon nanotubes, and antioxidant 1010 were mixed evenly and added. The mixture was fed into a twin-screw extruder, wherein the mass ratio of ultra-high molecular weight polyethylene to high-density polyethylene was 1:0.5, the addition amount of modified acidified multi-walled carbon nanotubes was 3.5% of the ultra-high molecular weight polyethylene, and the addition amount of antioxidant 1010 was 1.25% of the ultra-high molecular weight polyethylene. The mixture was melt-spun (the temperature range of the five zones of the screw during the melt spinning process was 270°C, 300°C, 310°C, 320°C, and 320°C), and cooled in a 40°C water bath to obtain ultra-high molecular weight polyethylene melt-spun fibers.

[0039] The surface of the high-strength ultra-high molecular weight polyethylene melt-spun fiber prepared in this comparative example is relatively smooth, and the fiber is uneven. After testing, the fiber fineness is (1324±22) dtex, and the strength is (26.77±1.59) cN / dtex.

[0040] Comparative Example 2 The preparation method of ultra-high molecular weight polyethylene fiber, the steps are as follows:

[0041] The sodium montmorillonite was evenly dispersed in deionized water, and the pH was adjusted to 7. Octadecyl trimethyl ammonium chloride was added in a mass ratio of sodium montmorillonite to octadecyl trimethyl ammonium chloride of 1:0.3. The mixture was stirred and reacted at room temperature for 0.5 h. After the reaction was completed, the mixture was filtered, dried at 60°C for 18 h, and ball-milled to obtain modified montmorillonite with a particle size of ≤50 μm. Ultra-high molecular weight polyethylene, high-density polyethylene, modified acidified multi-walled carbon nanotubes, modified montmorillonite, and antioxidant 1010 were evenly mixed and then put into a twin-screw extruder. The ultra-high molecular weight polyethylene The mass ratio of ultra-high molecular weight polyethylene and high-density polyethylene is 1:0.5, the addition amount of modified acidified multi-walled carbon nanotubes is 3.5% of the ultra-high molecular weight polyethylene, the addition amount of modified montmorillonite is 2.5% of the ultra-high molecular weight polyethylene, the addition amount of antioxidant 1010 is 1.25% of the ultra-high molecular weight polyethylene, and melt spinning (the temperature range of the five zones of the screw during the melt spinning process is 270°C, 300°C, 310°C, 320°C, 320°C), and cooling in a 40°C water bath to obtain high-strength ultra-high molecular weight polyethylene melt-spun fibers.

[0042] The surface of the high-strength ultra-high molecular weight polyethylene melt-spun fiber prepared in this comparative example is not smooth and the fiber is uneven. After testing, the fiber fineness is (1468±28) dtex and the strength is (24.81±0.99) cN / dtex.

[0043] Comparative Example 3 The preparation method of ultra-high molecular weight polyethylene fiber, the steps are as follows:

[0044] Ultra-high molecular weight polyethylene, high-density polyethylene, and antioxidant 1010 were mixed evenly and put into a twin-screw extruder, wherein the mass ratio of ultra-high molecular weight polyethylene to high-density polyethylene was 1:0.5, and the addition amount of antioxidant 1010 was 1.25% of the ultra-high molecular weight polyethylene, and melt spinning was performed. The results showed that melt spinning could not proceed smoothly and uniform fibers could not be obtained.

[0045] Example 2 The preparation method of the high-strength ultra-high molecular weight polyethylene melt-spun fiber of the present invention comprises the following steps:

[0046] Add multi-walled carbon nanotubes to a 30% hydrochloric acid solution at a mass ratio of 1:2.5 and stir evenly, add γ-(methacryloyloxy)propyltrimethoxysilane at a mass ratio of 1:0.8 to multi-walled carbon nanotubes and γ-(methacryloyloxy)propyltrimethoxysilane, heat to 30°C, stir and react for 2 hours to obtain modified acidified multi-walled carbon nanotubes; disperse sodium montmorillonite evenly in deionized water, adjust the pH to 7, add octadecyltrimethylammonium chloride at a mass ratio of 1:0.3 to sodium montmorillonite and octadecyltrimethylammonium chloride, stir and react at room temperature for 0.5 hours, filter after the reaction is completed, dry at 60°C for 18 hours, and ball mill to obtain modified montmorillonite with a particle size of ≤50μm; Ultra-high molecular weight polyethylene, high-density polyethylene, modified acidified multi-walled carbon nanotubes, modified montmorillonite and antioxidant 1010 are mixed evenly and put into a twin-screw extruder, wherein the mass ratio of ultra-high molecular weight polyethylene to high-density polyethylene is 1:0.5, the addition amount of modified acidified multi-walled carbon nanotubes is 3.5% of the ultra-high molecular weight polyethylene, the addition amount of modified montmorillonite is 2.5% of the ultra-high molecular weight polyethylene, and the addition amount of antioxidant 1010 is 1.25% of the ultra-high molecular weight polyethylene. Melt spinning (the temperature range of the five zones of the screw during the melt spinning process is 270°C, 300°C, 310°C, 320°C, 320°C), and cooling in a 40°C water bath to obtain high-strength ultra-high molecular weight polyethylene melt-spun fibers.

[0047] The high-strength ultra-high molecular weight polyethylene melt-spun fibers prepared in this embodiment have a smooth surface and are uniform. After testing, the fiber fineness is (1655±21) dtex and the strength is (32.03±1.74) cN / dtex.

[0048] Example 3 The preparation method of the high-strength ultra-high molecular weight polyethylene melt-spun fiber of the present invention comprises the following steps:

[0049] Add multi-walled carbon nanotubes to a 40% hydrochloric acid solution at a mass ratio of 1:2.5 and stir evenly, add γ-(methacryloyloxy)propyltrimethoxysilane at a mass ratio of 1:0.8 to multi-walled carbon nanotubes and γ-(methacryloyloxy)propyltrimethoxysilane, then heat to 30°C, stir and react for 2 hours to obtain modified acidified multi-walled carbon nanotubes; disperse sodium montmorillonite evenly in deionized water, adjust the pH to 7, add octadecyltrimethylammonium chloride at a mass ratio of 1:0.3 to sodium montmorillonite and octadecyltrimethylammonium chloride, stir and react at room temperature for 0.5 hours, filter after the reaction is completed, dry at 60°C for 18 hours, and ball mill to obtain modified montmorillonite with a particle size of ≤50μm; Ultra-high molecular weight polyethylene, high-density polyethylene, modified acidified multi-walled carbon nanotubes, modified montmorillonite and antioxidant 1010 are mixed evenly and put into a twin-screw extruder, wherein the mass ratio of ultra-high molecular weight polyethylene to high-density polyethylene is 1:0.5, the addition amount of modified acidified multi-walled carbon nanotubes is 3.5% of the ultra-high molecular weight polyethylene, the addition amount of modified montmorillonite is 2.5% of the ultra-high molecular weight polyethylene, and the addition amount of antioxidant 1010 is 1.25% of the ultra-high molecular weight polyethylene. Melt spinning (the temperature range of the five zones of the screw during the melt spinning process is 270°C, 300°C, 310°C, 320°C, 320°C), and cooling in a 40°C water bath to obtain high-strength ultra-high molecular weight polyethylene melt-spun fibers.

[0050] The high-strength ultra-high molecular weight polyethylene melt-spun fibers prepared in this embodiment have a smooth surface and are uniform. After testing, the fiber fineness is (1620±21) dtex and the strength is (32.77±1.57) cN / dtex.

[0051] Example 4 The preparation method of the high-strength ultra-high molecular weight polyethylene melt-spun fiber of the present invention comprises the following steps:

[0052] Add multi-walled carbon nanotubes to a 40% hydrochloric acid solution at a mass ratio of 1:2.5 and stir evenly, add γ-(methacryloyloxy)propyltrimethoxysilane at a mass ratio of 1:0.5, then heat to 30°C, stir and react for 2 hours to obtain modified acidified multi-walled carbon nanotubes; evenly disperse sodium montmorillonite in deionized water, adjust the pH to 7, add octadecyltrimethylammonium chloride at a mass ratio of 1:0.3 to sodium montmorillonite, stir and react at room temperature for 0.5 hours, filter after the reaction is completed, dry at 60°C for 18 hours, and ball mill to obtain modified montmorillonite with a particle size of ≤50μm; Ultra-high molecular weight polyethylene, high-density polyethylene, modified acidified multi-walled carbon nanotubes, modified montmorillonite and antioxidant 1010 are mixed evenly and put into a twin-screw extruder, wherein the mass ratio of ultra-high molecular weight polyethylene to high-density polyethylene is 1:0.5, the addition amount of modified acidified multi-walled carbon nanotubes is 3.5% of the ultra-high molecular weight polyethylene, the addition amount of modified montmorillonite is 2.5% of the ultra-high molecular weight polyethylene, and the addition amount of antioxidant 1010 is 1.25% of the ultra-high molecular weight polyethylene. Melt spinning (the temperature range of the five zones of the screw during the melt spinning process is 270°C, 300°C, 310°C, 320°C, 320°C), and cooling in a 40°C water bath to obtain high-strength ultra-high molecular weight polyethylene melt-spun fibers.

[0053] The high-strength ultra-high molecular weight polyethylene melt-spun fibers prepared in this embodiment have a smooth surface and are uniform. After testing, the fiber fineness is (1550±26) dtex and the strength is (32.05±0.74) cN / dtex.

[0054] Example 5 The preparation method of the high-strength ultra-high molecular weight polyethylene melt-spun fiber of the present invention comprises the following steps:

[0055] Add multi-walled carbon nanotubes to a 40% hydrochloric acid solution at a mass ratio of 1:2.5 and stir evenly; add γ-(methacryloyloxy)propyltrimethoxysilane at a mass ratio of 1:1 to multi-walled carbon nanotubes and γ-(methacryloyloxy)propyltrimethoxysilane, heat to 30°C, stir and react for 2 hours to obtain modified acidified multi-walled carbon nanotubes; disperse sodium montmorillonite evenly in deionized water, adjust the pH to 7, add octadecyltrimethylammonium chloride at a mass ratio of 1:0.3 to sodium montmorillonite and octadecyltrimethylammonium chloride, stir and react at room temperature for 0.5 hours, filter after the reaction is completed, dry at 60°C for 18 hours, and ball mill to obtain modified montmorillonite with a particle size of ≤50μm; Ultra-high molecular weight polyethylene, high-density polyethylene, modified acidified multi-walled carbon nanotubes, modified montmorillonite and antioxidant 1010 are mixed evenly and put into a twin-screw extruder, wherein the mass ratio of ultra-high molecular weight polyethylene to high-density polyethylene is 1:0.5, the addition amount of modified acidified multi-walled carbon nanotubes is 3.5% of the ultra-high molecular weight polyethylene, the addition amount of modified montmorillonite is 2.5% of the ultra-high molecular weight polyethylene, and the addition amount of antioxidant 1010 is 1.25% of the ultra-high molecular weight polyethylene. Melt spinning (the temperature range of the five zones of the screw during the melt spinning process is 270°C, 300°C, 310°C, 320°C, 320°C), and cooling in a 40°C water bath to obtain high-strength ultra-high molecular weight polyethylene melt-spun fibers.

[0056] The high-strength ultra-high molecular weight polyethylene melt-spun fibers prepared in this embodiment have a smooth surface and are uniform. After testing, the fiber fineness is (1568±30) dtex and the strength is (31.51±1.98) cN / dtex.

[0057] Example 6 The preparation method of ultra-high molecular weight polyethylene fiber, the steps are as follows:

[0058] Add multi-walled carbon nanotubes to a 35% hydrochloric acid solution at a mass ratio of 1:2.5 and stir evenly, add γ-(methacryloyloxy)propyltrimethoxysilane at a mass ratio of 1:0.8 to multi-walled carbon nanotubes and γ-(methacryloyloxy)propyltrimethoxysilane, then heat to 30°C, stir and react for 2 hours to obtain modified acidified multi-walled carbon nanotubes; disperse sodium montmorillonite evenly in deionized water, adjust the pH to 7, add octadecyltrimethylammonium chloride at a mass ratio of 1:0.3 to sodium montmorillonite and octadecyltrimethylammonium chloride, stir and react at room temperature for 0.5 hours, filter after the reaction is completed, dry at 60°C for 18 hours, and ball mill to obtain modified montmorillonite with a particle size of ≤50μm; Ultra-high molecular weight polyethylene, high-density polyethylene, modified acidified multi-walled carbon nanotubes, modified montmorillonite and antioxidant 1010 are mixed evenly and put into a twin-screw extruder, wherein the mass ratio of ultra-high molecular weight polyethylene to high-density polyethylene is 1:0.5, the addition amount of modified acidified multi-walled carbon nanotubes is 1.5% of the ultra-high molecular weight polyethylene, the addition amount of modified montmorillonite is 1.5% of the ultra-high molecular weight polyethylene, the addition amount of antioxidant 1010 is 1.25% of the ultra-high molecular weight polyethylene, and melt spinning (the temperature range of the five zones of the screw during the melt spinning process is 270°C, 300°C, 310°C, 320°C, 320°C), and cooling in a 40°C water bath to obtain high-strength ultra-high molecular weight polyethylene melt-spun fibers.

[0059] The surface of the high-strength ultra-high molecular weight polyethylene melt-spun fiber prepared in this comparative example is relatively smooth, and the fiber is uneven. After testing, the fiber fineness is (1543±28) dtex, and the strength is (30.97±1.57) cN / dtex.

[0060] Example 7 The preparation method of ultra-high molecular weight polyethylene fiber, the steps are as follows:

[0061] The multi-walled carbon nanotubes were added to a 35% hydrochloric acid solution at a mass ratio of 1:2.5 and stirred evenly. γ-(methacryloyloxy)propyltrimethoxysilane was added at a mass ratio of 1:0.8 for the multi-walled carbon nanotubes and γ-(methacryloyloxy)propyltrimethoxysilane, and the temperature was raised to 30°C. After stirring for 2 hours, modified acidified multi-walled carbon nanotubes were obtained. Sodium montmorillonite was evenly dispersed in deionized water, the pH was adjusted to 7, octadecyltrimethylammonium chloride was added at a mass ratio of 1:0.3 for the sodium montmorillonite and octadecyltrimethylammonium chloride, and the reaction was stirred at room temperature for 0.5 hours. After the reaction was completed, it was filtered, dried at 60°C for 18 hours, and ball milled to obtain modified montmorillonite with a particle size of ≤50μm. soil; ultra-high molecular weight polyethylene, high-density polyethylene, modified acidified multi-walled carbon nanotubes, modified montmorillonite, and antioxidant 1010 are uniformly mixed and put into a twin-screw extruder, wherein the mass ratio of ultra-high molecular weight polyethylene to high-density polyethylene is 1:0.5, the addition amount of modified acidified multi-walled carbon nanotubes is 5% of the ultra-high molecular weight polyethylene, the addition amount of modified montmorillonite is 5% of the ultra-high molecular weight polyethylene, and the addition amount of antioxidant 1010 is 1.25% of the ultra-high molecular weight polyethylene, melt spinning (the temperature range of the five zones of the screw during the melt spinning process is 270°C, 300°C, 310°C, 320°C, 320°C), and cooled in a 40°C water bath to obtain high-strength ultra-high molecular weight polyethylene melt-spun fibers.

[0062] The high-strength ultra-high molecular weight polyethylene melt-spun fibers prepared in this comparative example have a relatively smooth surface and are uneven in fiber quality. Upon testing, the fiber fineness is (1704±31) dtex and the strength is (33.04±1.61) cN / dtex.

[0063] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0064] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A method for preparing high-strength ultra-high molecular weight polyethylene melt-spun fibers, It is characterized in that The following steps are involved: S1, adding multi-walled carbon nanotubes to a hydrochloric acid solution and stirring evenly, adding γ-(methacryloyloxy)propyltrimethoxysilane and heating, stirring and reacting to obtain modified acidified multi-walled carbon nanotubes; S2, evenly dispersing sodium montmorillonite in deionized water, adjusting the pH to 6-7, adding octadecyltrimethylammonium chloride and stirring for reaction, filtering after the reaction is completed, drying, and ball milling to obtain modified montmorillonite; S3, mixing the ultra-high molecular weight polyethylene, high-density polyethylene, the modified acidified multi-walled carbon nanotubes obtained in step S1, the modified montmorillonite obtained in step S2, and an antioxidant uniformly, and then putting them into a twin-screw extruder for melt spinning and cooling in a water bath to obtain high-strength ultra-high molecular weight polyethylene melt-spun fibers.

2. The preparation method according to claim 1, It is characterized in that In the S1, the mass ratio of the multi-walled carbon nanotubes to γ-(methacryloyloxy)propyltrimethoxysilane is 1:(0.5-1).

3. The preparation method according to claim 1, It is characterized in that In the S1, the reaction temperature is 25°C to 35°C, and the reaction time is 1 to 3 hours.

4. The preparation method according to claim 1, It is characterized in that In S2, the mass ratio of the sodium montmorillonite to octadecyltrimethylammonium chloride is 1:(0.2-0.4).

5. The preparation method according to claim 4, It is characterized in that In S2, the mass ratio of the sodium montmorillonite to octadecyltrimethylammonium chloride is 1:0.

3.

6. The preparation method according to claim 1, It is characterized in that The particle size of the modified montmorillonite is ≤50 μm.

7. The preparation method according to claim 1, It is characterized in that In S3, the mass ratio of ultra-high molecular weight polyethylene to high-density polyethylene is 1:(0.2-0.8).

8. The preparation method according to claim 7, It is characterized in that In S3, the mass ratio of ultra-high molecular weight polyethylene to high-density polyethylene is 1:0.

5.

9. The preparation method according to claim 1, It is characterized in that In S3, the amount of modified acidified multi-walled carbon nanotubes added is 1.5% to 5% of the ultra-high molecular weight polyethylene, the amount of modified montmorillonite added is 1.5% to 5% of the ultra-high molecular weight polyethylene, and the amount of antioxidant added is 0.5% to 2% of the ultra-high molecular weight polyethylene.

10. A high-strength ultra-high molecular weight polyethylene melt-spun fiber, It is characterized in that Prepared by the method according to any one of claims 1 to 9.

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