A method for preparing ultra-high strength polyethylene colored fiber

Abstract

A method for preparing ultra-high strength polyethylene colored fiber, comprising the following steps: step 1, fiber twisting treatment, twisting the natural color polyethylene fiber according to the critical twist range to obtain twisted polyethylene fiber; step 2, fiber surface treatment, immersing the twisted polyethylene fiber in N-methylpyrrolidone solution, cleaning the polyethylene fiber surface oil and impurities, and the polyethylene fiber deposits a layer of NMP molecular substances in the N-methylpyrrolidone solution to obtain pretreated polyethylene fiber; step 3, fiber dyeing and coloring, immersing the pretreated polyethylene fiber in an aqueous coating coloring liquid for coloring, and obtaining polyethylene colored fiber; step 4, fiber drying treatment, infrared irradiation and drying the polyethylene colored fiber to obtain the final ultra-high strength polyethylene colored fiber. The fiber produced by the present invention has ultra-high strength and can be used for bowstring string materials in sports archery competitions.

Description

Technical Field

[0001] The invention belongs to the field of chemical fiber dyeing, and specifically relates to a method for preparing ultra-high strength polyethylene colored fiber using ultra-high molecular weight polyethylene fiber as raw material, which can be used for bowstring materials in archery competitions. Background Art

[0002] In 1963, the world's first UHMWPE was born in a laboratory of DSM in the Netherlands; in 1979, after numerous experiments, the mysterious veil of UHMWPE was unveiled, and DSM pioneered the gel spinning process and obtained a patent; in 1989, the first bowstring made of UHMWPE fiber was born, marking the start of mass production of the fiber and its application in specific industries. In my country, in 1984, Donghua University carried out basic research on UHMWPE fiber, and successively cooperated with Ningbo Dacheng New Materials Co., Ltd., Hunan Zhongtai Special Equipment Co., Ltd., Beijing Tongyi Zhong New Materials Technology Co., Ltd. and other companies, and in 2000, UHMWPE fiber was gradually industrialized.

[0003] The application of foreign UHMWPE fiber in the field of bowstrings is very mature, while the development of UHMWPE fiber in my country started relatively late. Currently, it mainly continues to break through the mid-end production capacity. As for high-end production capacity, there is still a big gap compared with foreign leading companies. It is conceivable that there is a long way to go in the high-end application of archery sports, especially colored fibers.

[0004] At present, the domestic production of UHMWPE colored fibers is mainly achieved by melt spinning of masterbatch. During the high-temperature drawing process, the color will change, deviating from customer requirements, and the breaking strength of the obtained colored fiber is lower than that of the natural color fiber, which is difficult to use in high-end fields. In the prior art, patent CN11842251A discloses a method for post-dyeing fibers by mainly adding solvents and dyes to form a dye solution. When the fibers are colored and heat-treated and dried, the solvent evaporates, the dye molecules migrate, and the color of the obtained colored fibers cannot be controlled, deviating from the initial color requirements. In addition, patent CN113235317B discloses a method for post-dyeing fibers by forming a dye solution with an aqueous acrylic emulsion, an isocyanate curing agent and a dye. The curing agent is also known as a hardener. This method only considers the issue of whether the fiber can be colored, and ignores the phenomenon that the texture becomes stiff after the fiber is colored, making it difficult to perform secondary processing to produce fiber products. Summary of the invention

[0005] The purpose of the present invention is to overcome the deficiencies of the above-mentioned prior art and to provide a method for preparing ultra-high strength polyethylene colored fiber.

[0006] A method for preparing ultra-high strength polyethylene colored fiber comprises the following steps:

[0007] Step 1: Fiber twisting treatment: twisting the natural polyethylene fiber according to the critical twist range to obtain twisted polyethylene fiber;

[0008] Step 2, fiber surface treatment, immersing the twisted polyethylene fiber in an N-methylpyrrolidone solution to clean the surface oil and impurities of the polyethylene fiber, and depositing a layer of NMP molecular substances on the polyethylene fiber in the N-methylpyrrolidone solution to obtain a pretreated polyethylene fiber;

[0009] Step 3: dyeing the fibers, immersing the pretreated polyethylene fibers in an aqueous coating coloring liquid to color them, thereby obtaining polyethylene colored fibers;

[0010] Step 4: fiber drying treatment, drying the polyethylene colored fiber by infrared irradiation to obtain the final ultra-high strength polyethylene colored fiber.

[0011] As a further improvement, the critical twist described in step 1 is in the range of 60-85 twists / m. In the textile industry, it is generally believed that the higher the fiber twist, the stronger the tensile performance of the yarn will be. However, in fact, during the twisting process of the fiber, the tension is proportional to the twist at the beginning. As the twist increases, the tension will also increase. After reaching a critical point, the tension has a peak value. After this peak value, if the twist continues, the tension will decrease. Therefore, the fiber twist must be strictly controlled.

[0012] As a further improvement, the natural color polyethylene fiber described in step 1 has an initial tensile force of 55-65kgf and a linear density of 200-2400D.

[0013] As a further improvement, the N-methylpyrrolidone solution in step 2 includes NMP solvent and deionized water, with the mass ratio of NMP solvent to deionized water being 1:5-15. N-methylpyrrolidone is an environmentally friendly solvent with low toxicity, high boiling point and excellent dissolving ability.

[0014] As a further improvement, the aqueous coating coloring liquid in step 3 includes 10-18 parts of polymer, 10-25 parts of pigment, 3-5 parts of hyperdispersant and 65-80 parts of deionized water by weight. The main materials used are aqueous materials, the solvent is water, and the solute is aqueous macromolecular polymer, etc., avoiding the environmental protection problem of current industrial development.

[0015] As a further improvement, the high molecular polymer is a mixture of one or more of polyvinyl alcohol, polyvinyl pyrrolidone, polyvinyl acetate, alkyd resin and flexible epoxy resin. Among them, polyvinyl pyrrolidone is a high molecular polymer. The substance has excellent adhesion and is elastic and glossy after film formation. It can often be used as a fiber treatment agent and adhesive. When used on polyethylene fibers, it can provide an extremely soft and stable coating with a texture consistent with that of colored fibers spun out. Polyvinyl pyrrolidone can be used as the main component, supplemented by one or more of polyvinyl alcohol, polyvinyl acetate, alkyd resin and flexible epoxy resin to ensure the softness of the coating and improve the adhesion of the coating.

[0016] As a further improvement, the pigment is one of Pigment Black 7, Pigment White 6, Pigment Red 49:1, Pigment Green 7, Pigment Yellow 101 and Pigment Yellow 108, or a mixture of several of them.

[0017] As a further improvement, the hyperdispersant is one or a mixture of polyether hyperdispersant, polyester hyperdispersant, polyacrylate hyperdispersant and polyolefin hyperdispersant. As a surfactant, the molecular structure of the superdispersant contains two groups that are opposite in solubility and polarity, one of which is a shorter polar group, called a hydrophilic group. Its molecular structure characteristics make it easy to directional arrange on the surface of the material or the interface between the two phases, reduce the interfacial tension, and have a good dispersing effect on the aqueous dispersion system, which provides good compatibility and stability for the preparation of aqueous coating coloring liquid.

[0018] As a further improvement, in the infrared irradiation drying described in step 4, the heating tube power is 300-800W and the drying temperature is 45-65°C.

[0019] As a further improvement, the aqueous coating coloring liquid is prepared according to the following steps:

[0020] Under low-speed stirring at 200-500 r / min, first add deionized water, then add superdispersant to form a dispersion, then add pigment and high molecular polymer in sequence, and stir at high speed at 800-1200 r / min for 5-20 minutes to obtain an initial mixed solution;

[0021] After obtaining the initial stage mixed solution, the initial stage mixed solution is transferred to a sand mill for grinding for 30-90 minutes to obtain a middle stage mixed solution;

[0022] The mixed solution in the middle stage is filtered through a filter cloth to physically eliminate bubbles and obtain a pure and stable water-based coating coloring liquid.

[0023] Compared with the prior art, the present invention has the following beneficial technical effects:

[0024] By using UHMWPE natural color fiber and strictly controlling the twisting twist, the highest tensile value is obtained. At the same time, it is dyed with water-based coating coloring liquid and a super high strength UHMWPE colored fiber is produced by post-dyeing method. The fiber texture is consistent with the masterbatch spun colored fiber and is soft, with a variety of color options. The tensile strength can also reach the optimal value, which has broad market prospects. DETAILED DESCRIPTION

[0025] In order to further understand the features, technical means, specific objectives and functions of the present invention, the present invention is further described in detail below in conjunction with specific implementation methods.

[0026] The ultra-high strength fiber defined in the present invention refers to a fiber having a single-filament tensile strength value of 45 kgf or more.

[0027] Implementation Case 1

[0028] A method for preparing ultra-high strength polyethylene colored fiber comprises the following steps:

[0029] Step 1: According to the critical twist range, select the natural polyethylene fiber with an initial tension value of 58kgf and a linear density of 800D and twist it to 60 twists / m to obtain a twisted polyethylene fiber. At this time, the average tension value of the twisted polyethylene fiber is maintained in the range of 56-58kgf.

[0030] Step 2: Prepare N-methylpyrrolidone solution, weigh NMP solvent and deionized water in a mass ratio of 1:5.2, stir and mix to obtain N-methylpyrrolidone solution, immerse twisted polyethylene fiber with a twist of 60 twists / m in N-methylpyrrolidone solution for treatment, clean the oil and impurities on the surface of the twisted polyethylene fiber, and the immersion time is 5 seconds to obtain pretreated polyethylene fiber. By immersing in N-methylpyrrolidone solution, not only can the fiber impurities be effectively cleaned, but the twisted polyethylene fiber can also deposit a layer of NMP molecular substances in the N-methylpyrrolidone solution, so that it can better quickly and tightly adhere to the polymer coating.

[0031] Step 3: Prepare water-based coating coloring liquid. Under low-speed stirring at 200r / min, add 70 parts of deionized water, 3 parts of polyolefin hyperdispersant, 17 parts of Pigment Yellow 101, 9 parts of polyvinyl pyrrolidone, and 1 part of polyvinyl alcohol in sequence, totaling 100 parts. The stirring speed is increased to 1000r / min, high-speed stirring and dispersion is performed for 10 minutes, and then the mixture is transferred to a sand mill and ground for 45 minutes to obtain the coloring liquid. The coloring liquid is filtered through a nylon filter cloth to remove a small amount of precipitate and perform physical defoaming to obtain the final water-based coating coloring liquid. The 60 twist / m pretreated polyethylene fiber treated in step 2 is immersed in the water-based coating coloring liquid for coloring. The immersion time is 8 seconds to obtain polyethylene colored fiber.

[0032] Step 4: Drying treatment: subject the colored polyethylene fiber in step 3 to infrared irradiation, with a drying temperature of 45° C. and a drying time of 30 seconds to obtain the final ultra-high strength polyethylene colored fiber.

[0033] Through the above strict post-dyeing processing method, the final average tension of polyethylene colored fiber is still 56-58kgf, which is basically consistent with the initial tension of natural color fiber before coloring.

[0034] Implementation Case 2

[0035] A method for preparing ultra-high strength polyethylene colored fiber comprises the following steps:

[0036] Step 1: According to the critical twist range, select the natural fiber with an initial tension value of 60kgf and a linear density of 800D and twist it to 65 twists / m to obtain a twisted polyethylene fiber. At this time, the average tension value is maintained in the range of 57-60kgf.

[0037] Step 2: Prepare N-methylpyrrolidone solution, weigh NMP solvent and deionized water in a mass ratio of 1:5.5, stir and mix to obtain N-methylpyrrolidone solution, immerse twisted polyethylene fiber with a twist of 65 twists / m in N-methylpyrrolidone solution for treatment, clean the oil and impurities on the fiber surface, and the immersion time is 8 seconds to obtain pretreated polyethylene fiber. By immersing in N-methylpyrrolidone solution, not only can the fiber impurities be effectively cleaned, but the fiber can also deposit a layer of NMP molecular substances here, so that it can better quickly and tightly adhere to the polymer coating.

[0038] Step 3: Prepare water-based coating coloring liquid. Under low-speed stirring at 300r / min, add 70 parts of deionized water, 3.5 parts of polyolefin hyperdispersant, 16.5 parts of Pigment Yellow 101, 8 parts of polyvinyl pyrrolidone, and 2 parts of polyvinyl alcohol in sequence, totaling 100 parts. The stirring speed is increased to 1200r / min, high-speed stirring and dispersion is performed for 15 minutes, and then the mixture is transferred to a sand mill for grinding for 60 minutes to obtain the coloring liquid. The coloring liquid is filtered through a nylon filter cloth to remove a small amount of precipitate and perform physical defoaming to obtain the final water-based coating coloring liquid. The 65 twist / m pretreated polyethylene fiber treated in step 2 is immersed in the water-based coating coloring liquid for coloring. The immersion time is 10 seconds to obtain polyethylene colored fiber.

[0039] Step 4: Drying treatment: subject the colored polyethylene fiber in step 3 to infrared irradiation, with a drying temperature of 45° C. and a drying time of 30 seconds to obtain the final ultra-high strength polyethylene colored fiber.

[0040] Through the above strict post-dyeing processing method, the final average tensile force of the colored fiber is still 57-60kgf, the dosage of superdispersant is increased, the dispersion of the coloring liquid is more uniform and stable, and the fiber coloring effect is better.

[0041] Implementation Case 3

[0042] A method for preparing ultra-high strength polyethylene colored fiber comprises the following steps:

[0043] Step 1: According to the critical twist range, select the natural fiber with an initial tension value of 63kgf and a linear density of 800D and twist it to 70 twists / m to obtain a twisted polyethylene fiber. At this time, the average tension value is maintained in the range of 59-62kgf.

[0044] Step 2: Prepare N-methylpyrrolidone solution, weigh NMP solvent and deionized water in a mass ratio of 1:6.3, stir and mix to obtain N-methylpyrrolidone solution, immerse twisted polyethylene fiber with a twist of 70 twists / m in N-methylpyrrolidone solution for treatment, clean the oil and impurities on the fiber surface, and immerse for 10 seconds to obtain pretreated polyethylene fiber. By immersing in N-methylpyrrolidone solution, not only can the fiber impurities be effectively cleaned, but the fiber can also deposit a layer of NMP molecular substances here, so that it can better quickly and tightly adhere to the high molecular polymer coating in step three.

[0045] Step 3: Prepare water-based coating coloring liquid. Under low-speed stirring at 400r / min, add 70 parts of deionized water, 4 parts of polyolefin hyperdispersant, 16 parts of pigment yellow 108, 8 parts of polyvinyl pyrrolidone, and 2 parts of polyvinyl alcohol in sequence, totaling 100 parts. The stirring speed is increased to 1200r / min, high-speed stirring and dispersion is performed for 15 minutes, and then the mixture is transferred to a sand mill for grinding for 60 minutes to obtain a coloring liquid. The coloring liquid is filtered through a nylon filter cloth to remove a small amount of precipitate and perform physical defoaming to obtain the final water-based coating coloring liquid. The 70 twist / m pretreated polyethylene fiber treated in step 2 is immersed in the water-based coating coloring liquid for coloring. The immersion time is 10 seconds to obtain a polyethylene colored fiber.

[0046] Step 4: Drying treatment: subject the colored polyethylene fiber in step 3 to infrared irradiation, with a drying temperature of 50° C. and a drying time of 40 seconds to obtain the final ultra-high strength polyethylene colored fiber.

[0047] Through the above strict post-dyeing processing method, the final average tensile force of the colored fiber is still 59-62kgf. With the increase of drying temperature and time, the color fixation effect of the fiber after coloring is stronger.

[0048] Implementation Case 4

[0049] A method for preparing ultra-high strength polyethylene colored fiber comprises the following steps:

[0050] Step 1: According to the critical twist range, select the natural fiber with an initial tension value of 65kgf and a linear density of 800D and twist it to 75 twists / m to obtain a twisted polyethylene fiber. At this time, the average tension value is maintained in the range of 60-63kgf.

[0051] Step 2: Prepare N-methylpyrrolidone solution, weigh NMP solvent and deionized water in a mass ratio of 1:6.3, stir and mix to obtain N-methylpyrrolidone solution, immerse twisted polyethylene fiber with a twist of 75 twists / m in N-methylpyrrolidone solution for treatment, clean the oil and impurities on the fiber surface, and immerse for 12 seconds to obtain pretreated polyethylene fiber. By immersing in N-methylpyrrolidone solution, not only can the fiber impurities be effectively cleaned, but the fiber can also deposit a layer of NMP molecular substances here, so that it can better quickly and tightly adhere to the high molecular polymer coating in step three.

[0052] Step 3: Prepare water-based coating coloring liquid. Under low-speed stirring at 500r / min, add 70 parts of deionized water, 5 parts of polyolefin hyperdispersant, 15 parts of pigment yellow 108, 7.5 parts of polyvinyl pyrrolidone, 0.5 parts of polyvinyl alcohol, and 2 parts of flexible epoxy resin in sequence, totaling 100 parts. The stirring speed is increased to 1200r / min, high-speed stirring and dispersion is performed for 20 minutes, and then the mixture is transferred to a sand mill for grinding for 80 minutes to obtain the coloring liquid. The coloring liquid is filtered through a nylon filter cloth to remove a small amount of precipitate and perform physical defoaming to obtain the final water-based coating coloring liquid. The 75 twist / m natural color fiber treated in step 2 is immersed in the water-based coating coloring liquid for coloring. The immersion time is 15 seconds to obtain polyethylene colored fiber.

[0053] Step 4: Drying treatment: subject the colored fiber colored in step 3 to infrared irradiation, with a drying temperature of 50° C. and a drying time of 40 seconds to obtain the final ultra-high strength polyethylene colored fiber.

[0054] Through the above strict post-dyeing processing method, the final average tensile force of the colored fiber is still 60-63kgf. The addition of flexible epoxy resin makes the color coating bonded more firmly, resulting in a polyethylene colored fiber with more stable color fixation.

[0055] Comparative Example 1

[0056] The twisting degree of the natural polyethylene fiber is 100 twists / m, and the other steps and parameter conditions are the same as those in Example 1.

[0057] Comparative Example 2

[0058] The twisting twist of the natural polyethylene fiber is 120 twists / m, and the other steps and parameter conditions are the same as those in Example 2.

[0059] Comparative Example 3

[0060] The high molecular weight polymer used to prepare the water-based coating coloring liquid is entirely polyvinyl pyrrolidone, and the other steps and parameter conditions are the same as those in Example 3.

[0061] Comparative Example 4

[0062] The amount of high molecular polymer flexible epoxy resin used in preparing the water-based coating coloring liquid is increased by 50%, and the other steps and parameter conditions are the same as those in Example 4.

[0063] After testing, the performance comparison of the samples prepared in various embodiments and comparative examples is as follows:

[0064]

[0065] It can be seen that if the natural color polyethylene fiber is twisted continuously without considering the critical twist range, increasing the twist value will reduce the tensile strength of the fiber; if the high molecular polymer in the color coating is only polyvinyl pyrrolidone, although the coating is extremely soft, it has insufficient adhesion and is easy to fade; in addition, if the amount of flexible epoxy resin is increased, the adhesion and color fastness of the coating can be improved, but the epoxy resin coating is not as soft as polyvinyl pyrrolidone, the fiber texture becomes slightly harder, and the tensile strength will also be affected. Therefore, strictly controlling the twist of the natural color fiber and using extremely soft polymers to make the color coating is an efficient and effective process for preparing ultra-high strength polyethylene colored fibers.

[0066] Moreover, it can be seen from the above that the twisting range defined by the present invention can ensure that the tension value is within an appropriate range.

[0067] It should be noted that the above description is not a limitation of the present invention. Without departing from the creative concept of the present invention, any obvious replacement is within the protection scope of the present invention.

Claims

1. A method for preparing ultra-high strength polyethylene colored fiber, characterized in that: The following steps are involved: Step 1: Fiber twisting treatment: twisting the natural polyethylene fiber according to the critical twist range to obtain twisted polyethylene fiber; Step 2, fiber surface treatment, immersing the twisted polyethylene fiber in an N-methylpyrrolidone solution to clean the surface oil and impurities of the polyethylene fiber, and depositing a layer of NMP molecular substances on the polyethylene fiber in the N-methylpyrrolidone solution to obtain a pretreated polyethylene fiber; Step 3: dyeing the fibers, immersing the pretreated polyethylene fibers in an aqueous coating coloring liquid to color them, thereby obtaining polyethylene colored fibers; Step 4: fiber drying treatment, drying the polyethylene colored fiber by infrared irradiation to obtain the final ultra-high strength polyethylene colored fiber.

2. The method for preparing an ultra-high strength polyethylene colored fiber according to claim 1, characterized in that: The critical twist described in step 1 is in the range of 60-85 twists / m.

3. The method for preparing an ultra-high strength polyethylene colored fiber according to claim 1, characterized in that: The natural color polyethylene fiber described in step 1 has an initial tensile force of 55-65kgf and a linear density of 200-2400D.

4. The method for preparing an ultra-high strength polyethylene colored fiber according to claim 1, characterized in that: The N-methylpyrrolidone solution described in step 2 includes NMP solvent and deionized water, and the mass ratio of NMP solvent to deionized water is 1:5-15.

5. The method for preparing ultra-high strength polyethylene colored fiber according to claim 1, characterized in that: The aqueous coating coloring liquid described in step three comprises, by weight, 10-18 parts of high molecular polymer, 10-25 parts of pigment, 3-5 parts of hyperdispersant and 65-80 parts of deionized water.

6. The method for preparing ultra-high strength polyethylene colored fiber according to claim 5, characterized in that: The high molecular polymer is one or a mixture of polyvinyl alcohol, polyvinyl pyrrolidone, polyvinyl acetate, alkyd resin and flexible epoxy resin.

7. The method for preparing ultra-high strength polyethylene colored fiber according to claim 5, characterized in that: The pigment is one of pigment black 7, pigment white 6, pigment red 49:1, pigment green 7, pigment yellow 101 and pigment yellow 108, or a mixture of several of them.

8. The method for preparing ultra-high strength polyethylene colored fiber according to claim 5, characterized in that: The hyperdispersant is one or a mixture of polyether hyperdispersant, polyester hyperdispersant, polyacrylate hyperdispersant and polyolefin hyperdispersant.

9. The method for preparing ultra-high strength polyethylene colored fiber according to claim 1, characterized in that: In the infrared irradiation drying described in step 4, the heating tube power is 300-800W and the drying temperature is 45-65°C.

10. The method for preparing ultra-high strength polyethylene colored fiber according to claim 5, characterized in that: The aqueous coating coloring liquid is prepared according to the following steps. Under low-speed stirring at 200-500 r / min, first add deionized water, then add superdispersant to form a dispersion, then add pigment and high molecular polymer in sequence, and stir at high speed at 800-1200 r / min for 5-20 minutes to obtain an initial mixed solution; After obtaining the initial stage mixed solution, the initial stage mixed solution is transferred to a sand mill for grinding for 30-90 minutes to obtain a middle stage mixed solution; The mixed solution in the middle stage is filtered through a filter cloth to physically eliminate bubbles and obtain a pure and stable water-based coating coloring liquid.

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