A low-temperature environment-friendly impregnating liquid, a modification method of ultra-high molecular weight polyethylene fiber and modified ultra-high molecular weight polyethylene fiber

Abstract

The present application relates to a kind of modification technical field of polyethylene fiber, specifically related to a kind of low-temperature environmental protection impregnation liquid, the modification method of ultra-high molecular weight polyethylene fiber and modified ultra-high molecular weight polyethylene fiber.The present application first uses vacuum continuous plasma treatment to replace traditional one bath activation liquid to activate UHMWPE fiber, overcome the problem that traditional one bath activation liquid is difficult to deposit on UHMWPE fiber.Then, using low-temperature unblocking blocked isocyanate, oligomeric polyol, crosslinking agent, but py latex and deionized water are compounded to prepare a kind of low-temperature environmental protection impregnation liquid.The blocked isocyanate in the low-temperature environmental protection impregnation liquid of the present application is unblocked and reacts with polyol and crosslinking agent, and forms resin network structure with urethane structure;Latex in low-temperature environmental protection impregnation liquid can be co-vulcanized with rubber, so as to establish good interface bonding between fiber and rubber.

Description

Technical Field

[0001] This invention relates to the field of polyethylene fiber modification technology, and more specifically, to a low-temperature environmentally friendly impregnation solution, a method for modifying ultra-high molecular weight polyethylene fiber, and modified ultra-high molecular weight polyethylene fiber. Background Technology

[0002] Ultra-high molecular weight polyethylene (UHMWPE) fiber is currently the fiber with the highest specific strength and specific modulus in the world, and is considered one of the three major high-tech specialty fibers in the world, along with carbon fiber and aramid fiber. UHMWPE fiber, with its excellent mechanical properties such as high strength, high modulus, and low density, is widely used in bulletproof vests, ropes, marine applications, and other fields. With the rapid development of the rubber and plastics industry, fiber-reinforced rubber composites are evolving towards lighter weight, higher strength, and longer lifespan. UHMWPE fiber possesses advantages such as high strength, high modulus, abrasion and cut resistance, chemical resistance, lightweight properties, and low cost, thus better meeting the demand for lightweight, high-strength rubber products. However, the chemical inertness of the UHMWPE fiber surface results in weak interfacial bonding between it and rubber, significantly limiting its application in rubber products.

[0003] Currently, the most effective technology for enhancing fiber / rubber interfaces is the resorcinol-formaldehyde-latex (RFL) impregnation process. RFL impregnation is the most commonly used fiber surface treatment method in industry, significantly improving the interfacial adhesion between aramid, nylon, and polyester fibers and rubber. However, the impregnation solution for RFL impregnation requires the use of toxic resorcinol and formaldehyde; during open impregnation and high-temperature vulcanization, formaldehyde is easily released into the air, seriously endangering the health of workers and users. Due to these environmental and health concerns, the RFL impregnation process will inevitably be phased out in the future.

[0004] Furthermore, the curing temperature of the impregnation solution in the RFL impregnation process is relatively high, typically exceeding 200°C, which is far higher than the melting point of UHMWPE fibers (approximately 150°C). If UHMWPE fibers are treated with RFL impregnation, they will melt during the curing process before the impregnation solution has fully cured. Moreover, the one-bath activating solution in the RFL impregnation process is unlikely to be effective on the inert UHMWPE fibers, preventing the impregnation solution from establishing chemical bonds with the fibers (because the surface of UHMWPE fibers lacks any reactive groups). Therefore, the RFL impregnation process cannot be used to treat UHMWPE fibers. Summary of the Invention

[0005] To address the technical problem that the RFL impregnation process cannot be used to treat ultra-high molecular weight polyethylene fiber (hereinafter referred to as UHMWPE fiber), this invention provides a low-temperature environmentally friendly impregnation solution, a method for modifying ultra-high molecular weight polyethylene fiber, and modified ultra-high molecular weight polyethylene fiber.

[0006] This invention utilizes continuous vacuum plasma treatment to replace the traditional one-bath activation solution for activating UHMWPE fibers, overcoming the problem of the traditional one-bath activation solution's difficulty in depositing on UHMWPE fibers. This invention uses a low-temperature desealed blocked isocyanate, oligomeric polyol, crosslinking agent, butadiene-pyridine latex (also known as "styrene-butadiene-vinylpyridine (VP) latex"), and deionized water to prepare a low-temperature environmentally friendly impregnation solution. The low-temperature environmentally friendly impregnation solution provided by this invention has a curing temperature lower than the melting point of ultra-high molecular weight polyethylene fibers, and can be used for the modification of ultra-high molecular weight polyethylene fibers; after modification with the low-temperature environmentally friendly impregnation solution provided by this invention, the interfacial adhesion strength between ultra-high molecular weight polyethylene fibers and rubber is excellent.

[0007] One of the objectives of this invention is to provide a low-temperature environmentally friendly impregnation solution.

[0008] The low-temperature environmentally friendly impregnation solution comprises blocked isocyanate, polyol, crosslinking agent, butadiene-pyridine latex and deionized water; the unblocking temperature of the blocked isocyanate is below 130°C, preferably 100-130°C;

[0009] Based on a usage of 1L of deionized water, the dosages of each component are as follows:

[0010] The amount of blocked isocyanate is 0.1-0.5 mol, preferably 0.15-0.3 mol, for example 0.15 mol, 0.2 mol, 0.25 mol, or 0.3 mol;

[0011] The polyol is 0.01-0.25 mol, preferably 0.05-0.1 mol, for example 0.05 mol or 0.1 mol;

[0012] The crosslinking agent is 0.01-0.125 mol, preferably 0.025-0.05 mol, for example 0.025 mol or 0.05 mol.

[0013] Butadiene-pyridine latex 100-250g, preferably 150-200g, for example 200g;

[0014] The amount of butadiene-pyridine latex used is based on the solid content of the butadiene-pyridine latex.

[0015] Unlike existing impregnation solutions that use maleic anhydride-grafted polyolefins to construct resin network structures, the low-temperature environmentally friendly impregnation solution disclosed in this invention, after the blocked isocyanate is unblocked, reacts with polyols and crosslinking agents to construct a resin network structure with a urethane structure. VP latex particles in the low-temperature environmentally friendly impregnation solution are dispersed within this resin network structure, forming an interpenetrating network or interacting with each other. The low-temperature environmentally friendly impregnation solution containing the resin network structure and VP latex particles coats the surface of UHMWPE fibers to form a PIL layer. The highly reactive isocyanate groups in the PIL layer chemically bond with the oxygen functional groups of the UHMWPE fibers at high temperatures, connecting the UHMWPE fibers to the PIL layer. The VP latex has a structure similar to NR, containing a large number of carbon-carbon double bonds. During subsequent vulcanization, the VP latex in the PIL layer can co-crosslink with the natural rubber matrix, forming a rubber crosslinking network based on monosulfide and polysulfide bonds. This establishes an effective chemical bond between the UHMWPE fibers and the rubber matrix.

[0016] The end-capping agent of the blocked isocyanate can be methyl ethyl ketone oxime and / or dimethylimidazole. The isocyanate of the blocked isocyanate can be hexamethylene diisocyanate. Specifically, the blocked isocyanate can be methyl ethyl ketone oxime-terminated hexamethylene diisocyanate or dimethylimidazole-terminated hexamethylene diisocyanate.

[0017] The molecular weight of the polyol is ≤2000; the polyol is preferably selected from one or more of polyethylene glycol, polypropylene glycol, polytetrahydrofuran glycol, polycarbonate glycol, and hexanediol-adipic acid polyester. Specifically, the polyol may be selected from polyethylene glycol or polypropylene glycol with a molecular weight of about 300.

[0018] The crosslinking agent is selected from one or more of trimethylolpropane, trimethylolethane, glycerol, and triethanolamine. Specifically, the crosslinking agent can be glycerol or triethanolamine.

[0019] The solid content of the butadiene-pyridine latex can be selected within a wide range. As a preferred embodiment, the solid content of the butadiene-pyridine latex is 10wt%-40wt%. Specifically, the solid content of the butadiene-pyridine latex can be 40wt%.

[0020] The second objective of this invention is to provide a method for modifying ultra-high molecular weight polyethylene fibers.

[0021] The method for modifying ultra-high molecular weight polyethylene fiber includes impregnating the ultra-high molecular weight polyethylene fiber with the low-temperature environmentally friendly impregnation solution described in one of the invention objectives, drying, and curing.

[0022] The immersion temperature and immersion time can be those commonly used in the field. Specifically, the immersion temperature can be room temperature, such as 25°C; the immersion time can be approximately 3 seconds.

[0023] The drying temperature is lower than the conventional drying temperature in this field. Specifically, the drying temperature can be 90°C-120°C, preferably 100°C-110°C, for example, 100°C.

[0024] The drying time can be a conventional drying time in the art. Specifically, the drying time is 90-300 seconds, preferably 150-200 seconds, for example, 150 seconds.

[0025] The curing temperature is lower than the conventional curing temperature in this field. Specifically, the curing temperature is 120°C-140°C, preferably 130-140°C, for example, 130°C or 140°C.

[0026] The curing time can be a conventional curing time in this field. Specifically, the curing time is 90-300 seconds, preferably 150-200 seconds, for example, 150 seconds.

[0027] As a preferred embodiment, the modification method for ultra-high molecular weight polyethylene (UHMWPE) fibers involves pre-treating the UHMWPE fibers with vacuum continuous plasma before impregnation. High-energy particles in the oxygen plasma can attack the carbon-hydrogen bonds on the fiber surface, causing free radical reactions or chemical bond breakage, forming surface free radicals. These surface free radicals further react with oxygen to generate various oxygen-containing groups, such as carbonyl, hydroxyl, and carboxyl groups. Plasma treatment not only introduces chemical groups but also induces changes in the surface microstructure. The high-energy plasma bombardment of the fiber surface leads to a rougher surface microstructure, which increases the specific surface area and thus enhances surface activity and adhesion. This physical change facilitates greater interaction between the oxygen-containing groups and external substances (such as rubber or coatings). Pre-treating the UHMWPE fibers with vacuum continuous plasma before modification further improves the bonding force between the UHMWPE fibers and the impregnation solution.

[0028] The specific operation of the vacuum continuous plasma pretreatment can refer to existing conventional operations, and the parameters involved can be set conventionally. Specifically, the vacuum continuous plasma pretreatment includes: fixing ultra-high molecular weight polyethylene fibers onto a plasma treatment device, evacuating the vacuum, introducing oxygen, and performing plasma treatment in an oxygen atmosphere. The power of the plasma treatment device can be set to 200W, and the treatment time per unit area can be approximately 9 seconds.

[0029] One specific method for modifying the ultra-high molecular weight polyethylene fiber includes:

[0030] (1) At 25°C, a certain amount of blocked isocyanate, polyol and crosslinking agent are added to deionized water and stirred for 1-2 hours, and then a certain amount of butadiene-pyridine latex is added and stirred for 1-2 hours to prepare a low-temperature environmentally friendly impregnation solution.

[0031] (2) Fix the UHMWPE fiber on the plasma treatment equipment, evacuate and introduce oxygen. Under the oxygen atmosphere and at a power of 200W, perform plasma treatment. The treatment time per unit area is about 9s. After the plasma treatment is completed, UHMWPE-P fiber is obtained.

[0032] (3) Use the low-temperature environmentally friendly impregnation liquid prepared in step (1) to impregnate the UHMWPE-P fiber for about 3 seconds. After impregnation, the UHMWPE-P fiber is first dried at 100℃-110℃ for 150-200 seconds, and then cured at 130-140℃ for 150-200 seconds.

[0033] The third objective of this invention is to provide a modified ultra-high molecular weight polyethylene fiber.

[0034] The modified ultra-high molecular weight polyethylene fiber is obtained by any one of the modification methods described in the second objective of the invention.

[0035] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0036] The low-temperature environmentally friendly impregnation liquid provided by this invention has a curing temperature lower than the melting point of ultra-high molecular weight polyethylene fiber, and can be used for the modification of ultra-high molecular weight polyethylene fiber.

[0037] The low-temperature environmentally friendly impregnation solution provided by this invention can form a resin network structure with a urethane structure, which can firmly bond with UHMWPE fibers. The latex in the low-temperature environmentally friendly impregnation solution can undergo a co-vulcanization reaction with the rubber, thereby establishing a good interfacial bond between the fiber and the rubber. Therefore, after modification with the low-temperature environmentally friendly impregnation solution provided by this invention, the ultra-high molecular weight polyethylene fiber exhibits excellent interfacial adhesion strength with rubber.

[0038] This invention provides an environmentally friendly low-temperature impregnation method suitable for UHMWPE fibers. Through plasma pretreatment and an environmentally friendly impregnation process, this invention can enhance the chemical activity of the UHMWPE fiber surface, achieving chemical modification of the fiber surface and improving the interfacial bonding strength between the UHMWPE fiber and rubber. This method avoids the use of toxic, highly volatile formaldehyde, thus better meeting environmental protection requirements. Detailed Implementation

[0039] The present invention will now be described in detail with reference to specific embodiments. It should be noted that the following embodiments are only used to further illustrate the present invention and should not be construed as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made by those skilled in the art based on the content of the present invention are still within the scope of protection of the present invention.

[0040] Unless otherwise specified, all reagents used in the above embodiments are commercially available products.

[0041] The methyl ethyl ketone oxime-terminated hexamethylene diisocyanate is sourced from Adiya New Materials Co., Ltd., under the brand name Y202.

[0042] The dimethylimidazole-terminated hexamethylene diisocyanate was derived from Covestro Polymers (China) Co., Ltd. Imprafix 2794.

[0043] Polyethylene glycol is from Shanghai Aladdin Biochemical Technology Co., Ltd., with a molecular weight of 300, and is a standard chemical.

[0044] Polypropylene glycol is from Shanghai Aladdin Biochemical Technology Co., Ltd., with a molecular weight of 300, and is a standard chemical.

[0045] Butadiene-pyridine latex is from Jiangsu Yatai Chemical Co., Ltd.;

[0046] UHMWPE fiber is from Kyushu Interstellar Technology Co., Ltd., brand name JX99.

[0047] Example 1

[0048] (1) At 25°C, 0.15 mol of methyl ethyl ketone oxime-terminated hexamethylene diisocyanate, 0.05 mol of polyethylene glycol and 0.025 mol of glycerol were added to 1 L of deionized water and stirred for 1.5 hours. Then, 500 g of butadiene-pyridine latex (the solid content of butadiene-pyridine latex was 40 wt%) was added and stirred for 1.5 hours to prepare PIL impregnation solution.

[0049] (2) The UHMWPE fibers were pretreated with plasma to activate the fiber surface. The fibers were fixed on a plasma treatment device, and after evacuation, oxygen was introduced. Plasma treatment was performed under an oxygen atmosphere and at a power of 200W; the treatment time per unit area was approximately 9 seconds. The UHMWPE fibers after plasma pretreatment were designated as UHMWPE-P fibers.

[0050] (3) Modification treatment: The UHMWPE-P fiber was impregnated with the PIL impregnation solution prepared in step (1) for 3 seconds. The impregnated UHMWPE-P fiber was first dried at 100°C for 150 seconds, and then cured at 140°C for 150 seconds. The modified UHMWPE-P fiber was labeled as UHMWPE-PIL fiber.

[0051] Example 2

[0052] (1) At 25°C, 0.2 mol of methyl ethyl ketone oxime-terminated hexamethylene diisocyanate, 0.1 mol of polyethylene glycol and 0.05 mol of glycerol were added to 1 L of deionized water and stirred for 1.5 hours. Then, 500 g of butadiene-pyridine latex (the solid content of butadiene-pyridine latex was 40 wt%) was added and stirred for 1.5 hours to prepare PIL impregnation solution.

[0053] (2) The UHMWPE fibers were pretreated with plasma to activate the fiber surface. The fibers were fixed on a plasma treatment device, and after evacuation, oxygen was introduced. Plasma treatment was performed under an oxygen atmosphere and at a power of 200W; the treatment time per unit area was approximately 9 seconds. The UHMWPE fibers after plasma pretreatment were designated as UHMWPE-P fibers.

[0054] (3) Modification treatment: The UHMWPE-P fiber was impregnated with the PIL impregnation solution prepared in step (1) for 3 seconds. The impregnated UHMWPE-P fiber was first dried at 100°C for 150 seconds, and then cured at 140°C for 150 seconds. The modified UHMWPE-P fiber was labeled as UHMWPE-PIL fiber.

[0055] Example 3

[0056] (1) At 25°C, 0.2 mol of methyl ethyl ketone oxime-terminated hexamethylene diisocyanate, 0.1 mol of polyethylene glycol and 0.05 mol of glycerol were added to 1 L of deionized water and stirred for 1.5 hours. Then, 500 g of butadiene-pyridine latex (the solid content of butadiene-pyridine latex was 40 wt%) was added and stirred for 1.5 hours to prepare PIL impregnation solution.

[0057] (2) The UHMWPE fibers were pretreated with plasma to activate the fiber surface. The fibers were fixed on a plasma treatment device, and after evacuation, oxygen was introduced. Plasma treatment was performed under an oxygen atmosphere and at a power of 200W; the treatment time per unit area was approximately 9 seconds. The UHMWPE fibers after plasma pretreatment were designated as UHMWPE-P fibers.

[0058] (3) Modification treatment: The UHMWPE-P fiber was impregnated with the PIL impregnation solution prepared in step (1) for 3 seconds. The impregnated UHMWPE-P fiber was first dried at 100°C for 150 seconds, and then cured at 130°C for 150 seconds. The modified UHMWPE-P fiber was labeled as UHMWPE-PIL fiber.

[0059] Example 4

[0060] (1) At 25°C, 0.3 mol of methyl ethyl ketone oxime-terminated hexamethylene diisocyanate, 0.1 mol of polyethylene glycol and 0.05 mol of glycerol were added to 1 L of deionized water and stirred for 1.5 hours. Then, 500 g of butadiene-pyridine latex (the solid content of butadiene-pyridine latex was 40 wt%) was added and stirred for 1.5 hours to prepare PIL impregnation solution.

[0061] (2) The UHMWPE fibers were pretreated with plasma to activate the fiber surface. The fibers were fixed on a plasma treatment device, and after evacuation, oxygen was introduced. Plasma treatment was performed under an oxygen atmosphere and at a power of 200W; the treatment time per unit area was approximately 9 seconds. The UHMWPE fibers after plasma pretreatment were designated as UHMWPE-P fibers.

[0062] (3) Modification treatment: The UHMWPE-P fiber was impregnated with the PIL impregnation solution prepared in step (1) for 3 seconds. The impregnated UHMWPE-P fiber was first dried at 100°C for 150 seconds, and then cured at 140°C for 150 seconds. The modified UHMWPE-P fiber was labeled as UHMWPE-PIL fiber.

[0063] Example 5

[0064] (1) At 25°C, 0.25 mol of methyl ethyl ketone oxime-terminated hexamethylene diisocyanate, 0.1 mol of polyethylene glycol and 0.05 mol of glycerol were added to 1 L of deionized water and stirred for 1.5 hours. Then, 500 g of butadiene-pyridine latex (the solid content of butadiene-pyridine latex was 40 wt%) was added and stirred for 1.5 hours to prepare PIL impregnation solution.

[0065] (2) The UHMWPE fibers were pretreated with plasma to activate the fiber surface. The fibers were fixed on a plasma treatment device, and after evacuation, oxygen was introduced. Plasma treatment was performed under an oxygen atmosphere and at a power of 200W; the treatment time per unit area was approximately 9 seconds. The UHMWPE fibers after plasma pretreatment were designated as UHMWPE-P fibers.

[0066] (3) Modification treatment: The UHMWPE-P fiber was impregnated with the PIL impregnation solution prepared in step (1) for 3 seconds. The impregnated UHMWPE-P fiber was first dried at 100°C for 100 seconds, and then cured at 120°C for 120 seconds. The modified UHMWPE-P fiber was labeled as UHMWPE-PIL fiber.

[0067] Example 6

[0068] (1) At 25°C, 0.2 mol of dimethylimidazole-terminated hexamethylene diisocyanate, 0.1 mol of polyethylene glycol and 0.05 mol of glycerol were added to 1 L of deionized water and stirred for 1.5 hours. Then, 500 g of butadiene-pyridine latex (the solid content of butadiene-pyridine latex was 40 wt%) was added and stirred for 1.5 hours to prepare PIL impregnation solution.

[0069] (2) The UHMWPE fibers were pretreated with plasma to activate the fiber surface. The fibers were fixed on a plasma treatment device, and after evacuation, oxygen was introduced. Plasma treatment was performed under an oxygen atmosphere and at a power of 200W; the treatment time per unit area was approximately 9 seconds. The UHMWPE fibers after plasma pretreatment were designated as UHMWPE-P fibers.

[0070] (3) Modification treatment: The UHMWPE-P fiber was impregnated with the PIL impregnation solution prepared in step (1) for 3 seconds. The impregnated UHMWPE-P fiber was first dried at 100°C for 150 seconds, and then cured at 140°C for 150 seconds. The modified UHMWPE-P fiber was labeled as UHMWPE-PIL fiber.

[0071] Example 7

[0072] (1) At 25°C, 0.2 mol of methyl ethyl ketone oxime-terminated hexamethylene diisocyanate, 0.1 mol of polypropylene glycol and 0.05 mol of glycerol were added to 1 L of deionized water and stirred for 1.5 hours. Then, 500 g of butadiene-pyridine latex (the solid content of butadiene-pyridine latex was 40 wt%) was added and stirred for 1.5 hours to prepare PIL impregnation solution.

[0073] (2) The UHMWPE fibers were pretreated with plasma to activate the fiber surface. The fibers were fixed on a plasma treatment device, and after evacuation, oxygen was introduced. Plasma treatment was performed under an oxygen atmosphere and at a power of 200W; the treatment time per unit area was approximately 9 seconds. The UHMWPE fibers after plasma pretreatment were designated as UHMWPE-P fibers.

[0074] (3) Modification treatment: The UHMWPE-P fiber was impregnated with the PIL impregnation solution prepared in step (1) for 3 seconds. The impregnated UHMWPE-P fiber was first dried at 100°C for 150 seconds, and then cured at 140°C for 150 seconds. The modified UHMWPE-P fiber was labeled as UHMWPE-PIL fiber.

[0075] Example 8

[0076] (1) At 25°C, 0.2 mol of methyl ethyl ketone oxime-terminated hexamethylene diisocyanate, 0.1 mol of polypropylene glycol and 0.05 mol of triethanolamine were added to 1 L of deionized water and stirred for 1.5 hours. Then, 500 g of butadiene-pyridine latex (the solid content of butadiene-pyridine latex was 40 wt%) was added and stirred for 1.5 hours to prepare PIL impregnation solution.

[0077] (2) The UHMWPE fibers were pretreated with plasma to activate the fiber surface. The fibers were fixed on a plasma treatment device, and after evacuation, oxygen was introduced. Plasma treatment was performed under an oxygen atmosphere and at a power of 200W; the treatment time per unit area was approximately 9 seconds. The UHMWPE fibers after plasma pretreatment were designated as UHMWPE-P fibers.

[0078] (3) Modification treatment: The UHMWPE-P fiber was impregnated with the PIL impregnation solution prepared in step (1) for 3 seconds. The impregnated UHMWPE-P fiber was first dried at 100°C for 150 seconds, and then cured at 140°C for 150 seconds. The modified UHMWPE-P fiber was labeled as UHMWPE-PIL fiber.

[0079] Performance test

[0080] According to the provisions of the national standard GB / T2942-2009, H-extraction samples were prepared: the original UHMWPE and the UHMWPE-PIL fibers prepared in Examples 1-8 were placed in the H-extraction mold along with natural rubber (Yunnan rubber) and vulcanized at 15 MPa and 135°C for 40 min.

[0081] Test method: The H-pull force was determined according to the national standard GB / T 2942-2009 (Determination of static adhesive strength between vulcanized rubber and fiber cord, H-pull method).

[0082] The test results are shown in Table 1.

[0083] Table 1

[0084] sample H (pulling force, N) Original UHMWPE 54.1 Example 1 124.7 Example 2 136.5 Example 3 119.2 Example 4 128.5 Example 5 97.1 Example 6 121.2 Example 7 120.9 Example 8 116.4

[0085] Table 1 shows that the H-pull force of the original UHMWPE is only 54 N, while the H-pull force of the UHMWPE-PIL fibers prepared in Examples 1-8 is 97.1-136.5 N; compared with the original UHMWPE, the H-pull force of the UHMWPE-PIL fibers prepared in Examples 1-8 is increased by 79.8-152.7%. This indicates that the low-temperature environmentally friendly impregnation solution provided by the present invention can be used for the modification of ultra-high molecular weight polyethylene fibers; moreover, the modification method of the present invention can effectively improve the interfacial adhesion strength between UHMWPE fibers and rubber.

[0086] Compared with other embodiments, the curing temperature of Example 5 is lower. Compared with the UHMWPE-PIL fibers prepared in other embodiments, the H-pull force of the UHMWPE-PIL fibers prepared in Example 5 is lower. This indicates that, using the low-temperature environmentally friendly impregnation liquid and the modification method of the present invention, within the curing temperature range that achieves the purpose of the invention, the higher the curing temperature, the better the H-pull force and the better the modification effect.

[0087] It should be noted that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art can still modify the technical solutions described in the above embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A method for modifying ultra-high molecular weight polyethylene (UHMWPE) fiber, comprising impregnating the UHMWPE fiber with a low-temperature environmentally friendly impregnation solution, drying, and curing; and subjecting the UHMWPE fiber to vacuum continuous plasma pretreatment before impregnation. The low-temperature environmentally friendly impregnation solution comprises blocked isocyanate, polyol, crosslinking agent, butadiene-pyridine latex, and deionized water; the unblocking temperature of the blocked isocyanate is below 130°C. Based on a usage of 1L of deionized water, the dosages of each component are as follows: Blocked isocyanate 0.1-0.5 mol; Polypolyol 0.01-0.25 mol; Crosslinking agent 0.01-0.125 mol; Butadiene-pyridine latex 100-250g; in, The amount of butyl pyridine latex used is based on the solid content of the butyl pyridine latex; The end-capping agent for the blocked isocyanate is methyl ethyl ketone oxime and / or dimethyl imidazole; The isocyanate of the blocked isocyanate is hexamethylene diisocyanate; The molecular weight of the polyol is ≤2000.

2. The modification method as described in claim 1, characterized in that, The crosslinking agent is selected from one or more of trimethylolpropane, trimethylolethane, glycerol, and triethanolamine.

3. The modification method as described in claim 1, characterized in that, The solid content of the butyl-pyridine latex is 10wt%-40wt%.

4. The modification method as described in claim 1, characterized in that, The unblocking temperature of the blocked isocyanate is 100-130℃.

5. The modification method as described in claim 1, characterized in that, Based on a usage of 1L of deionized water: The amount of blocked isocyanate is 0.15-0.3 mol; The amount of polyol is 0.05-0.1 mol; The crosslinking agent is 0.025-0.05 mol; Butadiene-pyridine latex is 150-200g.

6. The modification method as described in claim 1, characterized in that, The polyol is selected from one or more of polyethylene glycol, polypropylene glycol, polytetrahydrofuran glycol, and polycarbonate glycol.

7. The modification method as described in claim 1, characterized in that, The drying temperature is 90-120℃; or / and, Drying time is 90-300 seconds; or / and, The curing temperature is 120-140℃; or / and, The curing time is 90-300 seconds.

8. The modification method as described in claim 1, characterized in that, The drying temperature is 100-110℃; or / and, Drying time is 150-200 seconds; or / and, The curing temperature is 130-140℃; or / and, The curing time is 150-200 seconds.

9. The modification method as described in claim 1, characterized in that, The vacuum continuous plasma pretreatment includes: Ultra-high molecular weight polyethylene fibers are fixed on a plasma treatment device, and after evacuation, oxygen is introduced to perform plasma treatment in an oxygen atmosphere.

10. A modified ultra-high molecular weight polyethylene fiber, obtained by the modification method described in any one of claims 1-9.