A method for constructing a gradient anti-aging coating layer on the surface of nylon webbing based on plasma surface activation, and the nylon webbing.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-04-17
- Publication Date
- 2026-08-14
AI Technical Summary
但对尼龙66织带这类柔性、纤维束状、动态变形显著的基材而言，此类技术仍普遍存在附着不牢、无机相脆性偏大、厚涂层影响手感与弯折性能等问题
[0028]1、通过等离子体活化在尼龙表面引入活性官能团，配合界面层中硅烷偶联剂形成的预交联网络，以及马来酸酐接枝聚烯烃弹性体与基材氨基形成的酰胺键，实现了包覆层与基材间的双重化学锚定。这种界面层组分的协同作用，消除了物理界面产生的应力集中，显著提升了附着牢度与耐磨性，确保在反复弯折下不脱层、不开裂。
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Abstract
Description
Technical Field
[0001] This invention relates to a method for constructing a gradient anti-aging coating layer on the surface of nylon webbing based on plasma surface activation, and to the nylon webbing itself, belonging to the field of material surface modification and webbing functional finishing technology. Background Technology
[0002] Nylon 66 webbing is widely used in outdoor equipment, safety protection, bag accessories, industrial strapping, automotive interiors, and pet leashes due to its high strength, abrasion resistance, fatigue resistance, and dimensional stability. However, during long-term use, nylon 66 webbing is often exposed to ultraviolet radiation, air oxidation, humid and hot environments, friction, and repeated bending, which can easily lead to problems such as yellowing, molecular chain breakage, surface powdering, decreased mechanical properties, and shortened service life. Therefore, it is necessary to perform surface anti-aging modification treatment.
[0003] In existing technologies, UV absorbers, antioxidants, resin emulsions, or silicone finishing agents are typically applied directly to the surface of nylon webbing using methods such as padding, spraying, or coating to form a protective film, thereby slowing down the corrosion of the substrate by UV light, oxygen, and moisture. However, the adhesion between this protective film and the nylon 66 webbing usually relies mainly on physical adhesion, resulting in limited interfacial bonding strength. Under long-term friction, bending, washing, or humid and hot conditions, problems such as delamination, cracking, and functional degradation are prone to occur.
[0004] Other technologies employ plasma to pretreat the surface of nylon fibers, fabrics, or films to increase surface energy, improve wettability, and introduce a certain number of surface-active groups, thereby enhancing the adhesion of subsequent coatings or finishing solutions. While this approach can improve surface adhesion conditions, most only treat plasma treatment as an auxiliary step before ordinary finishing, lacking a systematic design targeting the hierarchical structure of anti-aging functional layers.
[0005] Some technologies employ nano-silica, organosilicon resin, polyurethane resin, and anti-aging additives to construct organic-inorganic composite coatings, thereby improving the material's weather resistance, surface abrasion resistance, and protective properties. However, for flexible, fibrous substrates like nylon 66 webbing, which exhibit significant dynamic deformation, these technologies still generally suffer from problems such as poor adhesion, excessive brittleness of the inorganic phase, and thick coatings affecting the feel and bending performance. Summary of the Invention
[0006] The purpose of this invention is to provide a method for constructing a gradient anti-aging coating layer on the surface of nylon webbing based on plasma surface activation, and the nylon webbing itself. By constructing an integrated covalent network through plasma activation and gradient coating, the anti-ultraviolet, heat-oxidation, damp heat and wear-bending properties of the nylon webbing are significantly improved.
[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows:
[0008] A method for constructing a gradient anti-aging coating layer on the surface of nylon webbing based on plasma surface activation includes the following steps:
[0009] S1: Plasma surface activation treatment is applied to nylon webbing;
[0010] S2: Construct an interfacial bonding layer on the surface of plasma-activated nylon webbing;
[0011] The interface bonding layer is formed by impregnation and pre-drying of an interface treatment solution containing a silane coupling agent, a maleic anhydride-grafted polyolefin elastomer, and a terminal epoxy hyperbranched polysiloxane.
[0012] S3: Build an anti-aging functional layer on the interface bonding layer;
[0013] The anti-aging functional layer is formed by impregnation, pre-curing and thermosetting of an anti-aging treatment liquid containing terminal amino polyetheramine, reactive ultraviolet absorber, reactive hindered amine light stabilizer, reactive hindered phenol antioxidant, epoxy-modified nano SiO2 sol and amino-modified nano CeO2.
[0014] Preferably, in step S1, the plasma surface activation treatment uses an Ar / O2 mixed gas with a volume ratio of Ar to O2 of (90-98):(2-10), a treatment power of 100-300W, a treatment distance of 2-10mm, and a treatment time of 5-60s.
[0015] Preferably, in step S2, the interface treatment solution comprises the following components in parts by weight: 1-5 parts KH-560, 1-5 parts KH-550, 50-90 parts ethanol, 10-30 parts water, 0.5-5 parts maleic anhydride grafted polyolefin elastomer POE-g-MAH, 0.5-3 parts terminal epoxy hyperbranched polysiloxane EHPSi, and the pH is adjusted to 3-5 by a pH adjuster.
[0016] The soaking time is 1-5 minutes; the pre-drying temperature is 80-110℃ and the time is 2-10 minutes.
[0017] Preferably, the preparation method of terminal epoxy hyperbranched polysiloxane EHPSi is to carry out hydrolysis and condensation polymerization of methyltriethoxysilane and dimethyldiethoxysilane at 70-85℃ for 3-5 hours under acidic conditions; then add epoxy silane coupling agent as end group modifier, and remove by-products after reaction to obtain the product;
[0018] The molar ratio of methyltriethoxysilane to dimethyldiethoxysilane and epoxysilane coupling agent is 1:(1-1.1):(0.3-0.6).
[0019] Preferably, in step S3, the anti-aging treatment solution comprises the following components in parts by weight: 3-8 parts of epoxy-modified nano-SiO2 sol, 1-6 parts of epoxy-containing benzotriazole UV absorber (2-(2'-hydroxy-4'-(2'',3''-epoxypropoxy)phenyl)-5-chlorobenzotriazole), 0.5-5 parts of maleimide-containing hindered amine light stabilizer HALS-MI, 0.5-4 parts of epoxy-containing hindered phenolic antioxidant antioxidant-EP, 5-15 parts of amino-terminated polyether amine, 0.5-5 parts of amino-modified nano-CeO2, 0.05-1 part of tertiary amine catalyst, and 30-80 parts of organic solvent.
[0020] Preferably, the hindered amine light stabilizer HALS-MI containing maleimide groups is prepared by carrying out an addition reaction between maleic anhydride and 4-amino-2,2,6,6-tetramethylpiperidine in a solvent; adding acetic anhydride and anhydrous sodium acetate, and carrying out a dehydration and ring-closure reaction at 40-60°C for 3-6 hours; after the reaction is completed, the product is purified by neutralization, washing, drying, and concentration.
[0021] The molar ratio of maleic anhydride to 4-amino-2,2,6,6-tetramethylpiperidine is (1-1.2):1.
[0022] Preferably, the antioxidant-EP is prepared by reacting 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid with epichlorohydrin at 70-85°C for 5-8 hours under the action of a phase transfer catalyst and at a pH of 9.0-10.5; after the reaction, the residue is removed by distillation and recrystallized to obtain the product.
[0023] The molar ratio of 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid to epichlorohydrin is 1:(3-7).
[0024] Preferably, in step S3, the impregnation time is 1-8 min; the pre-curing temperature is 70-100℃ and the time is 5-20 min; the heat curing temperature is 100-150℃ and the time is 10-30 min.
[0025] Preferably, the nylon webbing undergoes pretreatment before plasma treatment, which involves immersing the nylon webbing in an alcohol solution, rinsing it with deionized water, and finally drying it at 60-100°C for 15-60 minutes.
[0026] Nylon webbing prepared using any of the methods described above.
[0027] The beneficial effects of this invention are as follows:
[0028] 1. By introducing active functional groups onto the nylon surface through plasma activation, combined with the pre-crosslinked network formed by the silane coupling agent in the interface layer, and the amide bonds formed by the maleic anhydride-grafted polyolefin elastomer and the amino groups of the substrate, dual chemical anchoring between the coating layer and the substrate is achieved. This synergistic effect of the interface layer components eliminates stress concentration caused by the physical interface, significantly improves adhesion and wear resistance, and ensures that the coating does not delaminate or crack under repeated bending.
[0029] 2. The functional components are reactively modified to covalently anchor them in the three-dimensional cross-linked network of polyetheramine through Michael addition or epoxy-amino ring-opening reaction. Because the functional components and the film-forming medium form an integrated structure, the problems of migration, volatilization, or loss of additives in complex environments are fundamentally solved, enabling the webbing to maintain extremely high strength retention even under long-term UV irradiation, high temperature, and washing conditions.
[0030] 3. By utilizing the flexible multi-branched structure of hyperbranched polysiloxane in the interface layer and the synergistic effect of polyetheramine in the functional layer, a gradient modulus transition zone from a rigid substrate to a flexible surface was constructed. This structure can effectively absorb and disperse external impact and bending stress, while maintaining the original high strength of the nylon substrate, and endowing the coating layer with excellent bending resistance and fatigue resistance.
[0031] 4. The reactive UV absorber effectively shields UV light, the hindered amine light stabilizer captures free radicals, and the antioxidant decomposes peroxides. Combined with the multiple protective functions of modified nano-cerium dioxide, a comprehensive synergistic anti-aging system is formed. This chemical synergy between components can simultaneously block photodegradation and thermal oxidation processes, significantly reducing the yellowing index of the webbing during aging and maintaining the structural integrity of the material.
[0032] 5. The high-density cross-linking nodes provided by hyperbranched polysiloxane, in synergy with the in-situ generated silicon-oxygen bond network, significantly improve the density of the coating layer. This dense system not only effectively blocks the penetration of oxygen and moisture, but also ensures the chemical stability and physical protection of the material under high temperature and high humidity environments through the hydrolysis resistance of polyetheramine, preventing moisture absorption, stickiness, and strength degradation. Attached Figure Description
[0033] Figure 1 This is a schematic diagram of the gradient anti-aging coating structure on the surface of nylon 66 webbing. Detailed Implementation
[0034] Preparation of antioxidant-EP (epoxy-containing hindered phenolic antioxidant).
[0035] In a 500 mL four-necked flask equipped with a stirrer, thermometer, dropping funnel, and condenser, 0.1 mol of 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid and 0.5 mol of epichlorohydrin were added. 0.005 mol of tetrabutylammonium bromide was added as a phase transfer catalyst, the mixture was stirred, and the temperature was raised to 75 °C. A 30% (w / w) NaOH aqueous solution (0.12 mol / w) was slowly added dropwise over 2 hours. The pH of the reaction system was maintained between 9.0 and 10.5 during the addition. After the addition was complete, the reaction was continued at this temperature for 5 hours.
[0036] After the reaction was complete, the mixture was allowed to stand and separate into layers. The organic phase was collected. Most of the epichlorohydrin was removed by atmospheric distillation, and the remaining epichlorohydrin was completely removed by vacuum distillation. The residue was recrystallized from a mixed solvent of petroleum ether / ethyl acetate, filtered, and dried to obtain antioxidant EP.
[0037] Preparation of HALS-MI (a hindered amine light stabilizer containing maleimide groups).
[0038] Under ice-water bath conditions, 0.1 mol of maleic anhydride was dissolved in 150 mL of dichloromethane. 100 mL of a dichloromethane solution containing 0.1 mol of 4-amino-2,2,6,6-tetramethylpiperidine was slowly added dropwise, controlling the dropping rate to keep the system temperature below 10 °C. After the addition was complete, the mixture was stirred at room temperature for 2 h, and then 0.15 mol of acetic anhydride and 0.02 mol of anhydrous sodium acetate were added. The temperature was raised to 50 °C, and the reaction was allowed to proceed for 4 h.
[0039] After the reaction was completed, the system was cooled and poured into ice water. The pH was adjusted to neutral with saturated sodium carbonate solution. The organic phase was separated, washed with water, dried, concentrated, and purified by silica gel column chromatography to obtain a hindered amine light stabilizer containing maleimide groups, denoted as HALS-MI.
[0040] Preparation of EHPSi (terminated epoxy group hyperbranched polysiloxane).
[0041] 1 mol of methyltriethoxysilane, 1 mol of dimethyldiethoxysilane, and 200 mL of ethanol were added to a reaction vessel. 0.01 mol of hydrochloric acid and 3.5 mol of deionized water were added, and the mixture was hydrolyzed and polycondensed at 75 °C for 4 h. Then, 0.5 mol of KH-560 (epoxysilane) was added as an end-group modifier, and the reaction was continued for another 3 h. After the reaction was completed, ethanol and byproducts were removed under reduced pressure to obtain a terminal epoxy hyperbranched polysiloxane, denoted as EHPSi.
[0042] Preparation of epoxy-modified SiO2.
[0043] 20g of nano-silica sol with a solid content of 30% was adjusted to pH 4.5, and 0.5g of KH-560 was added. The mixture was stirred at 60℃ for 6h to obtain SiO2 sol with surface-grafted epoxy groups.
[0044] Preparation of amino-modified CeO2.
[0045] 20g of nano-cerium dioxide powder was dispersed in ethanol, 0.6g of KH-550 was added, and the mixture was ultrasonically treated for 2h. The temperature was then raised to 80℃ and refluxed for 4h. After centrifugation and washing, the powder was redispersed in ethanol for later use.
[0046] Example 1
[0047] (1) Substrate pretreatment.
[0048] Immerse the nylon 66 webbing (150 mm long, 50 mm wide, and 1.5 mm thick) in anhydrous ethanol for 10 minutes to remove surface oil and residual finishing agents; then rinse with deionized water and dry at 80°C for 30 minutes.
[0049] (2) Plasma surface activation.
[0050] The dried nylon 66 webbing was placed in a plasma treatment device and treated with Ar / O2 mixed plasma (volume ratio 95:5) at a power of 150W, a treatment distance of 4mm, and a treatment time of 10s.
[0051] Immediately proceed with the next coating step after processing to reduce the degradation of the webbing surface activity.
[0052] (3) Interface integration layer construction.
[0053] Prepare the interface treatment solution according to the following mass proportions:
[0054] KH-560: 2.5 copies;
[0055] KH-550: 2.5 portions;
[0056] Ethanol: 70 parts;
[0057] Water: 20 parts;
[0058] Glacial acetic acid: Adjust pH to 4;
[0059] POE-g-MAH (maleic anhydride grafted POE, commercially available, grafting rate 1-1.3%): 2 parts;
[0060] EHPSi: 1 part.
[0061] After mixing water and ethanol, glacial acetic acid was added to adjust the pH to 4. Then, KH-560 and KH-550 were added to the system for pre-hydrolysis for 5 minutes. POE-g-MAH and EHPSi were then added and stirred until homogeneous to obtain the interface treatment solution.
[0062] Then, the plasma-activated nylon 66 webbing was immersed in the interface treatment solution for 2 minutes, removed and gently squeezed to remove the liquid, and then pre-dried at 90°C for 5 minutes to allow the interface layer to be initially formed.
[0063] (4) Construction of anti-aging functional layer.
[0064] Prepare the anti-aging treatment solution according to the following mass proportions:
[0065] Epoxy-modified SiO2 sol: 5 parts;
[0066] 2-(2'-hydroxy-4'-(2'',3''-epoxypropoxy)phenyl)-5-chlorobenzotriazole (reactive UV absorber): 3 parts;
[0067] HALS-MI: 2 copies;
[0068] Antioxidant-EP: 1.5 parts;
[0069] Amino-terminated polyetheramine (average molecular weight 5000, ammonia value 1.5-2.0 mmol / g, commercially available): 8 parts;
[0070] Amino-modified CeO2: 1.5 parts;
[0071] 2,4,6-Tris(dimethylaminomethyl)phenol: 0.2 parts;
[0072] Ethanol / water (7 / 3, v / v) mixed solvent: 50 parts.
[0073] Epoxy-modified SiO2 sol and amino-modified CeO2 were ultrasonically dispersed in an ethanol / water mixed solvent. 2-(2'-hydroxy-4'-(2'',3''-epoxypropoxy)phenyl)-5-chlorobenzotriazole, HALS-MI, and antioxidant-EP were dissolved in the above system. Then, terminal amino polyetheramine and 2,4,6-tris(dimethylaminomethyl)phenol were added and stirred evenly to obtain an anti-aging treatment solution.
[0074] The treated nylon 66 webbing was immersed in the anti-aging treatment solution for 3 minutes, then removed and gently squeezed to remove the liquid. It was then pre-cured at 80°C for 10 minutes and then heat-cured at 120°C for 15 minutes.
[0075] A schematic diagram of the gradient anti-aging coating structure on the surface of the obtained nylon 66 webbing is shown below. Figure 1 As shown.
[0076] Comparative Example 1
[0077] It is basically the same as Example 1, except that no plasma surface activation treatment was performed.
[0078] Comparative Example 2
[0079] It is basically the same as Example 1, except that POE-g-MAH was not added to the interface treatment solution.
[0080] Comparative Example 3
[0081] It is basically the same as Example 1, except that EHPSi was not added to the interface treatment solution.
[0082] Comparative Example 4
[0083] The process is essentially the same as in Example 1, except that antioxidant-EP is replaced with a common commercial hindered phenolic antioxidant (antioxidant 1010) in the anti-aging treatment solution.
[0084] Comparative Example 5
[0085] The process is basically the same as in Example 1, except that the hindered amine light stabilizer HALS is used instead of HALS-MI in the anti-aging treatment solution.
[0086] Comparative Example 6
[0087] The process is basically the same as in Example 1, except that water-based polyurethane resin is used instead of amino-terminated polyetheramine in the anti-aging treatment solution.
[0088] Comparative Example 7
[0089] It is basically the same as Example 1, except that the anti-aging treatment solution uses unmodified SiO2 sol and CeO2.
[0090] The performance of the nylon 66 webbing obtained from Example 1 and Comparative Examples 1-7 was tested; the test methods are as follows:
[0091] Tensile strength test: Refer to GB / T 23318-2009 "Textiles - Determination of tensile properties of webbing and safety belts".
[0092] UV aging test: Conducted according to GB / T 16422.3-2014, using a UVA-340 lamp, irradiance of 0.89 W / m² / nm@340nm, black panel temperature of 60±3℃, no spraying, continuous irradiation for 120 h. After aging, the samples were equilibrated under standard atmospheric conditions for 24 h before mechanical property testing and yellowing index testing.
[0093] Yellowing index test: The test was conducted in accordance with GB / T 8424.3-2020 "Textiles - Tests for color fastness - Determination of whiteness and yellowness index".
[0094] Thermo-oxidative aging test: conducted in accordance with GB / T 3512-2014, with an aging chamber temperature of 85±2℃, an air exchange rate of 3-10 times / h, and an aging time of 72 h.
[0095] Damp heat aging test: The test was conducted in accordance with GB / T 2423.3-2016. The test conditions were: temperature 70±2℃, relative humidity 95±3% RH, and aging time 72 h.
[0096] Adhesion strength test: The test was conducted in accordance with FZ / T 01010-2012 "Determination of adhesion of coating on coated fabrics".
[0097] Abrasion resistance test: conducted according to the Martindale method of GB / T 21196.2-2007. The abrasive was standard wool abrasive, the load was 12 kPa, and the number of friction cycles was 5000.
[0098] Repeated bending test: Conducted in accordance with GB / T 12586-2003, bending angle 180°, bending frequency 60 times / min, bending radius 5 mm, total number of bends 1000.
[0099] The results are shown in Table 1-5.
[0100] Table 1: Basic mechanical properties of different samples before aging
[0101] Comparative Example 1 2385 24.5 Comparative Example 2 2378 24.2 Comparative Example 3 2365 23.8 Comparative Example 4 2370 23.5 Comparative Example 5 2375 24.0 Comparative Example 6 2320 21.5 Comparative Example 7 2380 23.9 Example 1 2382 24.3
[0102] Table 2: Performance results after 120 h of UV aging
[0103] Comparative Example 1 1520 63.7 11.8 48.2 22.5 Comparative Example 2 1550 65.2 13.5 55.8 19.8 Comparative Example 3 1680 71.0 15.2 63.9 16.5 Comparative Example 4 1800 76.0 16.5 70.2 14.0 Comparative Example 5 1910 80.4 17.8 74.2 11.5 Comparative Example 6 1750 75.4 14.2 66.0 15.5 Comparative Example 7 2050 86.1 19.5 81.6 8.5 Example 1 2205 92.6 22.1 91.0 5.5
[0104] Table 3: Performance results after 72 h of thermo-oxidative aging
[0105] Comparative Example 1 1650 69.2 13.8 56.3 Noticeably yellowed and powdery on the surface Comparative Example 2 1710 71.9 14.2 58.7 Yellowing, with localized cracks Comparative Example 3 1820 76.9 15.5 65.1 Slightly yellow Comparative Example 4 1900 80.2 16.5 70.2 Mostly intact, slightly yellowed Comparative Example 5 1980 83.4 17.2 71.7 The surface is intact and slightly yellow. Comparative Example 6 1860 80.2 14.5 67.4 Localized hardening and cracking Comparative Example 7 2100 88.2 19.0 79.5 The surface is intact and slightly yellowed. Example 1 2215 93.0 21.8 89.7 The surface is intact and there is no yellowing.
[0106] Table 4: Performance results after 72 hours of damp heat aging
[0107] Comparative Example 1 1700 71.3 Severe delamination Sticky, yellowing Comparative Example 2 1750 73.6 Local delamination Peeling edges, slightly yellow Comparative Example 3 1850 78.2 slight delamination Uneven distribution, slightly yellow Comparative Example 4 1920 81.0 A small amount of peeling Localized edge cracking Comparative Example 5 2000 84.2 none The surface is relatively intact and slightly yellow. Comparative Example 6 1880 81.0 slight delamination Localized hardening, fine lines Comparative Example 7 2120 89.1 none Surface intact, slightly hygroscopic Example 1 2210 92.8 none The surface is intact and does not absorb moisture.
[0108] Table 5: Results of adhesion strength, abrasion resistance and flexural properties
[0109] Comparative Example 1 Level 1 The coating has peeled off over a large area, exposing the fibers. Severe cracking, powdery shedding Comparative Example 2 Level 2 Significant wear and tear, with some areas showing the substrate. The surface is cracked and peeling. Comparative Example 3 Level 2-3 The surface shows obvious wear, and the functional layer is thinner. Localized fine cracks, peeling edges Comparative Example 4 Level 3 Slight wear, thinning of functional layer A few edge cracks Comparative Example 5 Level 4 Relatively intact, with minor scratches Basically intact, without cracks Comparative Example 6 Level 2-3 Localized wear Localized hardening and the appearance of fine cracks Comparative Example 7 Level 4-5 Complete, with slight scratches Complete, without cracks Example 1 Level 5 Complete, with no visible wear. Complete, without cracks
[0110] As shown in Tables 1-5, Example 1 performed best in all aging and mechanical tests. Regarding aging performance, Example 1, due to the use of reactive additives and covalent fixation, achieved a strength retention rate exceeding 92% after both UV and thermo-oxidative aging, significantly higher than Comparative Examples 4 and 5 using ordinary additives. This demonstrates the crucial role of chemical bonding in preventing additive migration and loss. In terms of interfacial adhesion, Comparative Example 1, without plasma activation, exhibited extremely poor adhesion (Grade 1), while Example 1, through multiple chemical anchoring, achieved Grade 5, significantly improving wear resistance and delamination resistance. Regarding flexibility, Example 1, benefiting from its gradient modulus design, remained intact after 2000 bends, while Comparative Examples 2 and 3, lacking the flexible component (POE-g-MAH or EHPSi), showed cracking or peeling. This fully illustrates the synergistic effect of the gradient coating structure and covalent crosslinking system of this invention.
[0111] Comparative Example 6, using waterborne polyurethane resin instead of end-amino polyetheramine, showed significantly lower strength and elongation retention rates after UV aging compared to Example 1. After thermo-oxidative aging, it exhibited localized hardening and cracking; after humid heat aging, it showed slight delamination; and after bending, fine cracks appeared. This is partly due to the relatively poor weather resistance of ordinary waterborne polyurethane, and partly because ordinary waterborne polyurethane cannot form an integrated structure with functional components, leading to additive migration, coating embrittlement, and decreased interfacial adhesion. Comparative Example 7, using unmodified nano-SiO2 and CeO2, showed inferior strength and elongation retention rates, as well as yellowing index and surface condition after humid heat aging compared to Example 1. This is because unmodified nanoparticles cannot be chemically anchored in the cross-linked network, easily agglomerating and migrating during long-term aging, thus weakening its UV shielding and humid heat resistance effects.
Claims
1. A method for constructing a gradient anti-aging coating layer on the surface of nylon webbing based on plasma surface activation, characterized in that, Includes the following steps: S1: Plasma surface activation treatment is applied to nylon webbing; S2: Construct an interfacial bonding layer on the surface of plasma-activated nylon webbing; The interface bonding layer is formed by impregnation and pre-drying of an interface treatment solution containing a silane coupling agent, a maleic anhydride-grafted polyolefin elastomer, and a terminal epoxy hyperbranched polysiloxane. S3: Build an anti-aging functional layer on the interface bonding layer; The anti-aging functional layer is formed by impregnation, pre-curing and thermosetting of an anti-aging treatment liquid containing terminal amino polyetheramine, reactive ultraviolet absorber, reactive hindered amine light stabilizer, reactive hindered phenol antioxidant, epoxy-modified nano SiO2 sol and amino-modified nano CeO2.
2. The method according to claim 1, characterized in that, In step S1, the plasma surface activation treatment uses an Ar / O2 mixed gas with a volume ratio of Ar to O2 of (90-98):(2-10), a treatment power of 100-300W, a treatment distance of 2-10mm, and a treatment time of 5-60s.
3. The method according to claim 1, characterized in that, In step S2, the interface treatment solution contains the following components in parts by weight: 1-5 parts KH-560, 1-5 parts KH-550, 50-90 parts ethanol, 10-30 parts water, 0.5-5 parts maleic anhydride grafted polyolefin elastomer POE-g-MAH, 0.5-3 parts terminal epoxy hyperbranched polysiloxane EHPSi, and the pH is adjusted to 3-5 by a pH adjuster. The soaking time is 1-5 minutes; the pre-drying temperature is 80-110℃ and the time is 2-10 minutes.
4. The method according to claim 3, characterized in that, The preparation method of epoxy-terminated hyperbranched polysiloxane EHPSi is to carry out hydrolysis and condensation polymerization of methyltriethoxysilane and dimethyldiethoxysilane at 70-85℃ for 3-5 hours under acidic conditions; then add epoxy silane coupling agent as end group modifier, and remove by-products after reaction to obtain the product; The molar ratio of methyltriethoxysilane to dimethyldiethoxysilane and epoxysilane coupling agent is 1:(1-1.1):(0.3-0.6).
5. The method according to claim 1, characterized in that, In step S3, the anti-aging treatment solution contains the following components in parts by weight: 3-8 parts of epoxy-modified nano-SiO2 sol, 1-6 parts of epoxy-containing benzotriazole UV absorber, 0.5-5 parts of maleimide-containing hindered amine light stabilizer HALS-MI, 0.5-4 parts of epoxy-containing hindered phenolic antioxidant antioxidant-EP, 5-15 parts of amino-terminated polyether amine, 0.5-5 parts of amino-modified nano-CeO2, 0.05-1 part of tertiary amine catalyst, and 30-80 parts of organic solvent.
6. The method according to claim 5, characterized in that, The hindered amine light stabilizer HALS-MI containing maleimide groups is prepared by reacting maleic anhydride with 4-amino-2,2,6,6-tetramethylpiperidine in a solvent via an addition reaction; then adding acetic anhydride and anhydrous sodium acetate, and carrying out a dehydration and ring-closure reaction at 40-60℃ for 3-6 h; after the reaction is completed, the product is purified by neutralization, washing, drying, and concentration. The molar ratio of maleic anhydride to 4-amino-2,2,6,6-tetramethylpiperidine is (1-1.2):
1.
7. The method according to claim 1, characterized in that, The preparation method of antioxidant-EP is to react 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid with epichlorohydrin at 70-85℃ for 5-8 hours under the action of a phase transfer catalyst and at a pH of 9.0-10.
5. After the reaction is completed, the residue is removed by distillation and recrystallized to obtain the product. The molar ratio of 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid to epichlorohydrin is 1:(3-7).
8. The method according to claim 1, characterized in that, In step S3, the impregnation time is 1-8 min; the pre-curing temperature is 70-100℃ and the time is 5-20 min; the heat curing temperature is 100-150℃ and the time is 10-30 min.
9. The method according to claim 1, characterized in that, Before plasma treatment, the nylon webbing undergoes a pretreatment process, which involves immersing the nylon webbing in an alcohol solution, rinsing it with deionized water, and finally drying it at 60-100℃ for 15-60 minutes.
10. Nylon webbing prepared by any one of the methods described in claims 1-9.