Low-temperature environment-friendly impregnation liquid, modification method of ultra-high molecular weight polyethylene fiber and modified ultra-high molecular weight polyethylene fiber

Abstract

The invention relates to the technical field of modification of polyethylene fibers, in particular to a low-temperature environment-friendly impregnation liquid, a modification method of ultra-high molecular weight polyethylene fibers and modified ultra-high molecular weight polyethylene fibers. According to the method, firstly, vacuum continuous plasma treatment is used for replacing a traditional one-bath activating solution to activate the UHMWPE fibers, and the problem that the traditional one-bath activating solution is difficult to deposit on the UHMWPE fibers is solved. Then, closed isocyanate which is deblocked at low temperature, oligomeric polyol, a cross-linking agent, butadiene-vinylpyridine rubber latex and deionized water are compounded to prepare the low-temperature environment-friendly steeping liquor. Blocked isocyanate in the low-temperature environment-friendly impregnation liquid is unblocked and then reacts with polyhydric alcohol and a cross-linking agent, and a resin network structure with a carbamate structure is constructed and formed; latex in the low-temperature environment-friendly steeping liquor can be subjected to co-vulcanization reaction with rubber, so that good interface bonding between the fibers and the rubber is established.

Description

Technical Field

[0001] The present invention relates to the technical field of polyethylene fiber modification, and more particularly to a low-temperature environmentally friendly impregnation liquid, a method for modifying ultra-high molecular weight polyethylene fibers, and modified ultra-high molecular weight polyethylene fibers. Background Art

[0002] Ultra-high molecular weight polyethylene (UHMWPE) fiber is the fiber with the highest specific strength and specific modulus in the world. It is one of the three major high-tech specialty fibers in the world today, along with carbon fiber and aramid fiber. UHMWPE fiber is widely used in bulletproof vests, cables, oceans and other fields due to its excellent mechanical properties, such as high strength, high modulus and low density. With the rapid development of the rubber and plastics industries, fiber-reinforced rubber composites are developing in the direction of light weight, high strength and long life. UHMWPE fiber has the advantages of high strength, high modulus, wear resistance and cut resistance, chemical resistance, light weight and low cost, so it better meets the demand for lightweight and high-strength rubber products. However, the chemical inertness of the surface of ultra-high molecular weight polyethylene fiber leads to weak interfacial bonding with rubber, which greatly limits its application in rubber products.

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

[0004] In addition, the curing temperature of the impregnation liquid in the RFL impregnation process is relatively high, usually exceeding 200°C, which is much higher than the melting point of UHMWPE fiber (about 150°C); if the RFL impregnation process is used to treat UHMWPE fiber, the UHMWPE fiber will melt during the curing process before the impregnation liquid is cured. Moreover, the one-bath activation liquid in the RFL impregnation process is difficult to take effect on the inert UHMWPE fiber, resulting in the impregnation liquid being unable to establish a chemical bond with the fiber (because there is no active group on the surface of the UHMWPE fiber that can react with it). Therefore, the RFL impregnation process cannot be used to treat UHMWPE fiber. Summary of the invention

[0005] In view of the technical problem that the RFL impregnation process cannot be used to treat ultra-high molecular weight polyethylene fibers (hereinafter referred to as UHMWPE fibers), the present invention provides a low-temperature environmentally friendly impregnation solution, a modification method for ultra-high molecular weight polyethylene fibers, and modified ultra-high molecular weight polyethylene fibers.

[0006] The present invention utilizes vacuum continuous plasma treatment to replace the traditional one-bath activation solution to activate UHMWPE fibers, thereby overcoming the problem that the traditional one-bath activation solution is difficult to deposit on UHMWPE fibers. The present invention uses low-temperature unblocked blocked isocyanate, oligomeric polyols, crosslinking agents, butylpyridine 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 the present invention has a solidification 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 the ultra-high molecular weight polyethylene fibers are modified with the low-temperature environmentally friendly impregnation solution provided by the present invention, the interfacial bonding strength between the fibers and the rubber is excellent.

[0007] One of the purposes of the present invention is to provide a low-temperature environmentally friendly impregnation liquid.

[0008] The low-temperature environmentally friendly impregnation liquid comprises blocked isocyanate, polyol, crosslinking agent, butylpyrrolidone latex and deionized water; the deblocking temperature of the blocked isocyanate is lower than 130° C., preferably 100-130° C.;

[0009] Based on 1L of deionized water, the dosage of each component is as follows:

[0010] Blocked isocyanate 0.1-0.5 mol, preferably 0.15-0.3 mol, such as 0.15 mol, 0.2 mol, 0.25 mol, 0.3 mol;

[0011] Polyol 0.01-0.25 mol, preferably 0.05-0.1 mol, such as 0.05 mol, 0.1 mol;

[0012] Cross-linking agent 0.01-0.125 mol, preferably 0.025-0.05 mol, for example 0.025 mol, 0.05 mol

[0013] 100-250 g of butylpyrrolidone latex, preferably 150-200 g, for example 200 g;

[0014] Wherein, the dosage of butylpyrrolidone latex is based on the solid content of butylpyrrolidone latex.

[0015] Unlike the existing impregnation liquid that uses maleic anhydride grafted polyolefin to construct a resin network structure, the blocked isocyanate in the low-temperature environmentally friendly impregnation liquid disclosed in the present invention reacts with polyols and cross-linking agents after unblocking to construct a resin network structure with a carbamate structure; the VP latex particles in the low-temperature environmentally friendly impregnation liquid are dispersed in the above-mentioned resin network structure to form an interpenetrating network or interaction. The low-temperature environmentally friendly impregnation liquid containing the resin network structure and VP latex particles is coated on the surface of the UHMWPE fiber to form a PIL layer. The highly active isocyanate groups in the PIL layer and the oxygen functional groups of the UHMWPE fiber establish a chemical bond at high temperature to connect the UHMWPE fiber to the PIL layer. VP latex has a structure similar to NR and contains a large number of carbon-carbon double bonds. In the subsequent vulcanization process, the VP latex in the PIL layer can be co-cross-linked with the natural rubber matrix to form a rubber cross-linking network based on monosulfide bonds and polysulfide bonds. Thereby, an effective chemical bond between the UHMWPE fiber and the rubber matrix is ​​established.

[0016] The blocking agent of the blocked isocyanate may be methyl ethyl ketone oxime or / and dimethyl imidazole. The isocyanate of the blocked isocyanate may be hexamethylene diisocyanate. Specifically, the blocked isocyanate may be hexamethylene diisocyanate blocked with methyl ethyl ketone oxime or hexamethylene diisocyanate blocked with dimethyl imidazole.

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

[0018] The cross-linking agent is selected from at least one of trimethylolpropane, trimethylolethane, glycerol and triethanolamine. Specifically, the cross-linking agent can be glycerol or triethanolamine.

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

[0020] A second object of the present invention is to provide a method for modifying ultra-high molecular weight polyethylene fibers.

[0021] The modification method of the ultra-high molecular weight polyethylene fiber comprises impregnating the ultra-high molecular weight polyethylene fiber with the low-temperature environmentally friendly impregnation liquid described in one of the purposes of the invention, drying, and curing.

[0022] The immersion temperature and immersion time may be conventional immersion temperatures and immersion time in the art. Specifically, the immersion temperature may be room temperature, such as 25° C., and the immersion time may be about 3 seconds.

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

[0024] The drying time may be the 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 the art. Specifically, the curing temperature is 120°C-140°C, preferably 130-140°C, such as 130°C or 140°C.

[0026] The curing time may be the conventional curing time in the art, specifically, the curing time is 90-300 seconds, preferably 150-200 seconds, for example 150 seconds.

[0027] As a preferred embodiment, the modification method of the ultra-high molecular weight polyethylene fiber, the ultra-high molecular weight polyethylene fiber is subjected to vacuum continuous plasma pretreatment before impregnation. The high-energy particles in the oxygen plasma can attack the carbon-hydrogen bonds on the fiber surface, free radical reactions or chemical bond ruptures occur, and surface free radicals are formed. These surface free radicals further react with oxygen to generate various oxygen-containing groups, such as carbonyl, hydroxyl, carboxyl, etc. Plasma treatment can not only introduce chemical groups, but also cause changes in the surface microstructure. High-energy plasma bombards the fiber surface, causing the surface microstructure to become rough, which will increase the specific surface area, and then enhance the activity and adhesion of the surface. This physical change helps the oxygen-containing groups to interact more with external substances (such as rubber or coating). After the ultra-high molecular weight polyethylene fiber is subjected to vacuum continuous plasma pretreatment and then subjected to modification treatment, the bonding force between the ultra-high molecular weight polyethylene fiber and the impregnation solution can be further improved.

[0028] The specific operation of the vacuum continuous plasma pretreatment can refer to the existing conventional operation, and the parameters involved can be set conventionally. Specifically, the vacuum continuous plasma pretreatment includes: fixing the ultra-high molecular weight polyethylene fiber on a plasma treatment device, introducing oxygen after vacuuming, 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 about 9s.

[0029] The modification method of the ultra-high molecular weight polyethylene fiber, wherein a specific scheme comprises:

[0030] (1) adding a certain amount of blocked isocyanate, polyol and crosslinking agent into deionized water at 25° C. and stirring for 1-2 hours, and then adding a certain amount of butylpyrrolidone latex and stirring for 1-2 hours to prepare a low-temperature environmentally friendly impregnation solution;

[0031] (2) The fiber UHMWPE is fixed on the plasma treatment equipment, and oxygen is introduced after vacuuming. In the oxygen atmosphere, the plasma treatment is carried out at a power of 200 W, and the treatment time per unit area is about 9 seconds. After the plasma treatment is completed, the UHMWPE-P fiber is obtained;

[0032] (3) The UHMWPE-P fiber is impregnated with the low-temperature environmentally friendly impregnation liquid prepared in step (1), and the impregnation time is about 3 seconds. The impregnated UHMWPE-P fiber is first dried at 100°C-110°C for 150-200 seconds, and then cured at 130-140°C for 150-200 seconds.

[0033] A third object of the present invention is to provide a modified ultra-high molecular weight polyethylene fiber.

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

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] The low-temperature environmentally friendly impregnating liquid provided by the present invention has a solidification temperature lower than the melting point of the ultra-high molecular weight polyethylene fiber and can be used for modifying the ultra-high molecular weight polyethylene fiber.

[0037] The low-temperature environmentally friendly impregnation liquid provided by the present invention can form a resin network structure with a carbamate structure, and the resin network structure with a carbamate structure can be firmly combined with the UHMWPE fiber; the latex in the low-temperature environmentally friendly impregnation liquid can undergo a co-vulcanization reaction with the rubber, thereby establishing a good interface bonding between the fiber and the rubber. Therefore, after the ultra-high molecular weight polyethylene fiber is modified with the low-temperature environmentally friendly impregnation liquid provided by the present invention, the interface bonding strength between the fiber and the rubber is excellent.

[0038] The present invention provides an environmentally friendly low-temperature impregnation method suitable for UHMWPE fibers. The present invention can improve the chemical activity of the UHMWPE fiber surface through plasma pretreatment and environmentally friendly impregnation process, realize chemical modification of the fiber surface, and improve the interface bonding strength between the UHMWPE fiber and rubber. The method avoids the use of toxic and highly volatile formaldehyde, and is more in line with environmental protection requirements. DETAILED DESCRIPTION

[0039] The present invention is described in detail below in conjunction with specific embodiments. It is necessary to point out that the following embodiments are only used to further illustrate the present invention and cannot be understood as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made to the present invention by those skilled in the art based on the contents of the present invention still fall within the scope of protection of the present invention.

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

[0041] Methyl ethyl ketone oxime-terminated hexamethylene diisocyanate was obtained from Adiya New Materials Co., Ltd., brand Y202;

[0042] Dimethylimidazole-terminated hexamethylene diisocyanate comes from Imprafix 2794 of Covestro Polymers (China) Co., Ltd.

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

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

[0045] Butylpyrrolidone latex was from Jiangsu Yatai Chemical Co., Ltd.;

[0046] The UHMWPE fiber comes from Jiuzhou Xingji Technology Co., Ltd., brand JX99.

[0047] Example 1

[0048] (1) At 25° C., 0.15 mol of methyl ethyl ketoxime-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 butylpyrrolidone latex (the solid content of butylpyrrolidone latex was 40 wt %) was added and stirred for 1.5 hours to prepare a PIL impregnation solution.

[0049] (2) The UHMWPE fiber is subjected to plasma pretreatment to activate the fiber surface. The fiber is fixed on a plasma treatment device, and oxygen is introduced after vacuuming. The plasma treatment is performed under an oxygen atmosphere at a power of 200 W; the treatment time per unit area is about 9 seconds. The UHMWPE fiber after plasma pretreatment is recorded as UHMWPE-P fiber.

[0050] (3) Modification treatment: The UHMWPE-P fiber was impregnated with the PIL impregnation liquid 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 marked as UHMWPE-PIL fiber.

[0051] Example 2

[0052] (1) At 25° C., 0.2 mol of methyl ethyl ketoxime-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 butylpyrrolidone latex (the solid content of butylpyrrolidone latex was 40 wt %) was added and stirred for 1.5 hours to prepare a PIL impregnation solution.

[0053] (2) The UHMWPE fiber is subjected to plasma pretreatment to activate the fiber surface. The fiber is fixed on a plasma treatment device, and oxygen is introduced after vacuuming. The plasma treatment is performed under an oxygen atmosphere at a power of 200 W; the treatment time per unit area is about 9 seconds. The UHMWPE fiber after plasma pretreatment is recorded as UHMWPE-P fiber.

[0054] (3) Modification treatment: The UHMWPE-P fiber was impregnated with the PIL impregnation liquid 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 marked as UHMWPE-PIL fiber.

[0055] Example 3

[0056] (1) At 25° C., 0.2 mol of methyl ethyl ketoxime-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 butylpyrrolidone latex (the solid content of butylpyrrolidone latex was 40 wt %) was added and stirred for 1.5 hours to prepare a PIL impregnation solution.

[0057] (2) The UHMWPE fiber is subjected to plasma pretreatment to activate the fiber surface. The fiber is fixed on a plasma treatment device, and oxygen is introduced after vacuuming. The plasma treatment is performed under an oxygen atmosphere at a power of 200 W; the treatment time per unit area is about 9 seconds. The UHMWPE fiber after plasma pretreatment is recorded as UHMWPE-P fiber.

[0058] (3) Modification treatment: The UHMWPE-P fiber was impregnated with the PIL impregnation liquid 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 marked as UHMWPE-PIL fiber.

[0059] Example 4

[0060] (1) At 25° C., 0.3 mol of methyl ethyl ketoxime-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 butylpyrrolidone latex (the solid content of butylpyrrolidone latex was 40 wt %) was added and stirred for 1.5 hours to prepare a PIL impregnation solution.

[0061] (2) The UHMWPE fiber is subjected to plasma pretreatment to activate the fiber surface. The fiber is fixed on a plasma treatment device, and oxygen is introduced after vacuuming. The plasma treatment is performed under an oxygen atmosphere at a power of 200 W; the treatment time per unit area is about 9 seconds. The UHMWPE fiber after plasma pretreatment is recorded as UHMWPE-P fiber.

[0062] (3) Modification treatment: The UHMWPE-P fiber was impregnated with the PIL impregnation liquid 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 marked as UHMWPE-PIL fiber.

[0063] Example 5

[0064] (1) At 25° C., 0.25 mol of methyl ethyl ketoxime-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 butylpyrrolidone latex (the solid content of butylpyrrolidone latex was 40 wt %) was added and stirred for 1.5 hours to prepare a PIL impregnation solution.

[0065] (2) The UHMWPE fiber is subjected to plasma pretreatment to activate the fiber surface. The fiber is fixed on a plasma treatment device, and oxygen is introduced after vacuuming. The plasma treatment is performed under an oxygen atmosphere at a power of 200 W; the treatment time per unit area is about 9 seconds. The UHMWPE fiber after plasma pretreatment is recorded as UHMWPE-P fiber.

[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 marked 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 propylene glycol were added to 1 L of deionized water and stirred for 1.5 hours. Then, 500 g of butylpyrrolidone latex (the solid content of butylpyrrolidone latex was 40 wt%) was added and stirred for 1.5 hours to prepare a PIL impregnation solution.

[0069] (2) The UHMWPE fiber is subjected to plasma pretreatment to activate the fiber surface. The fiber is fixed on a plasma treatment device, and oxygen is introduced after vacuuming. The plasma treatment is performed under an oxygen atmosphere at a power of 200 W; the treatment time per unit area is about 9 seconds. The UHMWPE fiber after plasma pretreatment is recorded as UHMWPE-P fiber.

[0070] (3) Modification treatment: The UHMWPE-P fiber was impregnated with the PIL impregnation liquid 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 marked as UHMWPE-PIL fiber.

[0071] Example 7

[0072] (1) At 25° C., 0.2 mol of methyl ethyl ketoxime-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 butylpyrrolidone latex (the solid content of butylpyrrolidone latex was 40 wt %) was added and stirred for 1.5 hours to prepare a PIL impregnation solution.

[0073] (2) The UHMWPE fiber is subjected to plasma pretreatment to activate the fiber surface. The fiber is fixed on a plasma treatment device, and oxygen is introduced after vacuuming. The plasma treatment is performed under an oxygen atmosphere at a power of 200 W; the treatment time per unit area is about 9 seconds. The UHMWPE fiber after plasma pretreatment is recorded as UHMWPE-P fiber.

[0074] (3) Modification treatment: The UHMWPE-P fiber was impregnated with the PIL impregnation liquid 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 marked as UHMWPE-PIL fiber.

[0075] Example 8

[0076] (1) At 25° C., 0.2 mol of methyl ethyl ketoxime-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 butylpyrrolidone latex (the solid content of butylpyrrolidone latex was 40 wt %) was added and stirred for 1.5 hours to prepare a PIL impregnation solution.

[0077] (2) The UHMWPE fiber is subjected to plasma pretreatment to activate the fiber surface. The fiber is fixed on a plasma treatment device, and oxygen is introduced after vacuuming. The plasma treatment is performed under an oxygen atmosphere at a power of 200 W; the treatment time per unit area is about 9 seconds. The UHMWPE fiber after plasma pretreatment is recorded as UHMWPE-P fiber.

[0078] (3) Modification treatment: The UHMWPE-P fiber was impregnated with the PIL impregnation liquid 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 marked as UHMWPE-PIL fiber.

[0079] Performance test

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

[0081] Test method: The H pull-out force is measured in accordance with the national standard GB / T 2942-2009 (H pull-out method for determination of static bond strength between vulcanized rubber and fiber cord).

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

[0083] Table 1

[0084] sample H Extraction 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 extraction force of the original UHMWPE is only 54N, while the H extraction force of the UHMWPE-PIL fibers prepared in Examples 1-8 is 97.1-136.5N; compared with the original UHMWPE, the H extraction force of the UHMWPE-PIL fibers prepared in Examples 1-8 is increased by 79.8-152.7%. This shows 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; and the modification method of the present invention can effectively improve the interfacial bonding strength between UHMWPE fibers and rubber.

[0086] Compared with other embodiments, the curing temperature of embodiment 5 is lower. Compared with the UHMWPE-PIL fibers prepared in other embodiments, the H extraction force of the UHMWPE-PIL fibers prepared in embodiment 5 is lower. It is shown that, by using the low-temperature environmentally friendly impregnation liquid and the modification method of the present invention, within the curing temperature range that can achieve the purpose of the invention, the higher the curing temperature, the better the H extraction force and the better the modification effect.

[0087] It should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention is 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 replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the scope of protection of the claims of the present invention.

Claims

1. A low-temperature environmentally friendly impregnation solution, comprising a blocked isocyanate, a polyol, a crosslinking agent, a butylpyrrolidone latex and deionized water; the deblocking temperature of the blocked isocyanate is lower than 130°C, preferably 100-130°C; Based on 1L of deionized water, the dosage of each component is as follows: Blocked isocyanate 0.1-0.5 mol, preferably 0.15-0.3 mol; Polyol 0.01-0.25 mol, preferably 0.05-0.1 mol; Cross-linking agent 0.01-0.125 mol, preferably 0.025-0.05 mol; 100-250g of butylpyrrolidone latex, preferably 150-200g; in, The amount of butylpyrrolidone latex used is based on the solid content of the butylpyrrolidone latex.

2. The low-temperature environmentally friendly impregnation liquid according to claim 1, characterized in that: The blocking agent of the blocked isocyanate is methyl ethyl ketone oxime or / and dimethyl imidazole; or / and, The isocyanate of the blocked isocyanate is hexamethylene diisocyanate.

3. The low-temperature environmentally friendly impregnation liquid according to claim 1, characterized in that: The molecular weight of the polyol is ≤2000, and is preferably selected from one or more of polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polycarbonate diol, and hexanediol-adipic acid polyester.

4. The low-temperature environmentally friendly impregnation liquid according to claim 1, characterized in that: The cross-linking agent is selected from at least one of trimethylolpropane, trimethylolethane, glycerol and triethanolamine.

5. The low-temperature environmentally friendly impregnation liquid according to claim 1, characterized in that: The solid content of the butylpyrrolidone latex is 10wt%-40wt%.

6. A method for modifying ultra-high molecular weight polyethylene fibers, comprising impregnating the ultra-high molecular weight polyethylene fibers with the low-temperature environmentally friendly impregnation solution described in any one of claims 1 to 5, drying, and curing.

7. The modification method according to claim 6, characterized in that: The drying temperature is 90-120°C, preferably 100-110°C; or / and, The drying time is 90-300 seconds, preferably 150-200 seconds; or / and, The curing temperature is 120-140°C, preferably 130-140°C; or / and, The curing time is 90-300 seconds, preferably 150-200 seconds.

8. The modification method according to claim 6 or 7, characterized in that: The ultra-high molecular weight polyethylene fibers were pretreated with vacuum continuous plasma before impregnation.

9. The modification method according to claim 8, characterized in that: The vacuum continuous plasma pretreatment comprises: The ultra-high molecular weight polyethylene fiber is fixed on the plasma treatment equipment, and oxygen is introduced after vacuuming, and the plasma treatment is performed in the oxygen atmosphere.

10. A modified ultra-high molecular weight polyethylene fiber obtained by the modification method according to any one of claims 6 to 9.