High-durability polyurethane bonding layer resin material

Abstract

The invention discloses a high-durability polyurethane bonding layer resin material, and belongs to the technical field of polyurethane. The invention discloses a high-durability polyurethane bonding layer resin material. The high-durability polyurethane bonding layer resin material is prepared from the following components: polyether polyol, isocyanate, chemically modified nano silicon dioxide, chemically modified graphene nanosheets, an ultraviolet light absorber, an antioxidant, a self-healing microcapsule and a catalyst. Through surface silane modification of the nanofiller and application of a microcapsule coating technology, enhancement and self-healing functions of the material are realized. The preparation process comprises the steps of filler modification, self-healing capsule synthesis, component dispersion, curing, heat treatment and the like. The material has excellent mechanical strength, heat resistance, ultraviolet resistance and oxidation resistance, has good microcrack self-repairing capacity, and is suitable for the field of high-performance structure bonding.

Description

Technical Field

[0001] The present invention relates to the technical field of polyurethane, and more particularly to a highly durable polyurethane adhesive layer resin material. Background Art

[0002] Polyurethane adhesive layer resins are widely used in various industrial fields, particularly in applications requiring high-performance bonding, such as aerospace, automotive, and electronic equipment. In recent years, as material performance requirements continue to increase, traditional polyurethane resins have gradually exposed certain shortcomings due to limitations in durability, impact resistance, and thermal stability. Therefore, the development of polyurethane adhesive layer resins with higher durability, excellent self-healing properties, and superior antioxidant and UV protection has become a key issue in improving the performance of these materials.

[0003] Currently, research on the modification of polyurethane adhesive layer resins focuses on improving their durability, antioxidant properties, UV resistance, thermal stability, and adhesion to substrates. Traditional modification methods include the addition of nanofillers (such as silica and graphene), UV absorbers, and antioxidants. The introduction of graphene, in particular, not only improves the mechanical properties of the resin material but also significantly enhances its thermal conductivity and antioxidant properties. Furthermore, modification of nanosilica can improve its dispersibility and interfacial adhesion with the resin, further enhancing the material's mechanical properties.

[0004] However, while existing polyurethane adhesive layer resin materials have achieved certain performance improvements, they can still develop surface damage such as scratches and cracks over long-term use, leading to a decline in mechanical properties. To address this issue, the introduction of self-healing technology in recent years has provided new insights into the application of polyurethane adhesive layer resin materials. The self-healing microcapsules, designed to release a healing agent when the material is damaged, rapidly repair cracks and extend the material's service life.

[0005] In the future, with the continued advancement of self-healing technology, nanotechnology, and multifunctional materials, polyurethane adhesive resin materials will develop towards higher performance, longer lifespan, and greater environmental friendliness. By further optimizing microcapsule preparation processes, modification methods, and multi-component system designs, technological breakthroughs in this field are expected to provide more reliable and efficient material solutions for a variety of industrial applications. Summary of the Invention

[0006] The object of the present invention is to provide a highly durable polyurethane adhesive layer resin material, which has excellent mechanical strength, heat resistance, UV resistance and oxidation resistance, and has good microcrack self-repairing ability, so that it has excellent durability.

[0007] A highly durable polyurethane adhesive layer resin material, comprising the following materials in parts by mass: (1) Polyether polyol, 100 parts; (2) Isocyanate, 40-50 parts; (3) Nano-silicon dioxide, 4-6 parts, the nano-silicon dioxide has a particle size of 20-60 nm and needs to be chemically modified; (4) 1-3 parts of graphene nanosheets, wherein the graphene nanosheets need to be chemically modified; (5) UV absorber, 0.8-1.2 parts; (6) Antioxidant, 0.4-0.6 parts; (7) Self-healing microcapsules, 6-10 parts, wherein the core material of the self-healing microcapsules is bisphenol A epoxy resin and the wall material is polyurethane resin; (8) Catalyst, 0.2-0.4 parts.

[0008] Preferably, the polyether polyol is polypropylene glycol with a molecular weight of 2000.

[0009] Preferably, the isocyanate is diphenylmethane diisocyanate.

[0010] Preferably, the modification step of the nano-silica is as follows: add isopropyl alcohol solvent and γ-aminopropyltriethoxysilane to a reaction container, stir evenly until completely dissolved, add deionized water and ammonia water, stir and react at room temperature for 40-60 minutes, add nano-silica, the mass ratio of the five is 100-120 parts: 4-6 parts: 20-30 parts: 1-2 parts: 10 parts, stir and react at room temperature for 4-6 hours, centrifuge, wash with deionized water and dry to obtain hydroxyl-terminated silane-modified nano-silica.

[0011] Preferably, the modification step of the graphene nanosheets is as follows: adding sulfuric acid and graphene nanosheets to a reaction vessel, stirring under ice bath conditions, slowly adding potassium permanganate to the solution, continuing to stir in the ice bath, controlling the temperature not to exceed 20°C, slowly adding deionized water to control the reaction solution to gradually heat up to 80-100°C, maintaining the temperature for 200-240 minutes, centrifuging, washing with sodium chloride solution, dispersing graphene oxide in deionized water, ultrasonically dispersing uniformly, slowly adding ammonia water, adjusting the pH value to 9-11, heating to 90-110°C, stirring the reaction for 20 minutes, The reaction mixture was stirred for 0-240 minutes, centrifuged, washed with deionized water and dried to obtain reduced graphene oxide nanosheets, and isopropyl alcohol solvent and γ-aminopropyltriethoxysilane were added to the reaction vessel in a mass ratio of 80-120 parts:10 parts:8-12 parts:20-40 parts:20-40 parts:2-4 parts. The mixture was ultrasonically dissolved and dispersed uniformly, and then the reduced graphene oxide nanosheets obtained previously were added. The reaction was stirred at room temperature for 100-140 minutes, centrifuged, washed with deionized water and dried to obtain hydroxyl-terminated silane-modified reduced graphene oxide nanosheets.

[0012] Preferably, the ultraviolet absorber is ultraviolet absorber UV-327.

[0013] Preferably, the antioxidant is antioxidant 1010.

[0014] Preferably, the preparation method of the self-healing microcapsules is as follows: add dichloromethane solvent and bisphenol A epoxy resin to a reaction vessel, ultrasonically disperse them uniformly to obtain an oil phase, add deionized water solvent, polyurethane resin, and surfactant hexadecyltrimethylammonium chloride to the reaction vessel to obtain an aqueous phase, and the mass ratio of the five is 60-100 parts: 10 parts: 60-100 parts: 11-15 parts: 0.1-0.5 parts, mix the oil phase and the aqueous phase, emulsify them with a high-speed homogenizer to obtain uniform droplets, stir at a speed of 4000-8000 rpm, polymerize at 40-80°C for 4-8 hours, remove the solvent by solvent evaporation, wash with deionized water and dry to obtain self-healing microcapsules.

[0015] Preferably, the catalyst is dibutyltin dilaurate.

[0016] Preferably, the preparation method comprises the following steps: S1. Accurately weighing the ingredients, modifying nano-silica and graphene nanosheets, and preparing self-healing microcapsules; S2, adding the modified nano-silica and graphene to the polyether polyol and uniformly dispersing them by ultrasonication; S3, adding ultraviolet absorber, antioxidant and self-healing microcapsules, and uniformly dispersing them by ultrasonication to form component A; S4, adding diphenylmethane diisocyanate as component B to component A, adding a catalyst, and stirring to disperse uniformly; S5. Curing at 70-90° C. for 100-140 minutes, followed by heat treatment at 100-140° C. for 50-70 minutes to obtain a highly durable polyurethane adhesive layer resin material.

[0017] Compared with the prior art, the advantages of the present invention are: (1) Improve the durability and UV resistance of materials The present invention effectively improves the ultraviolet stability of the material by using the ultraviolet absorber UV-327, prolongs the service life of the polyurethane adhesive layer resin material, and avoids the rapid degradation of material performance under ultraviolet irradiation.

[0018] (2) Enhance antioxidant capacity Adding antioxidant 1010 can significantly improve the antioxidant properties of resin materials, slow down the aging process under high temperature and oxygen, maintain the strength and toughness of the material, and ensure its long-term stable use.

[0019] (3) Self-healing function By introducing self-healing microcapsules (bisphenol A epoxy resin as the core material and polyurethane resin as the wall material), the material can automatically release repair agents to repair cracks and restore its original mechanical properties when it is damaged externally, greatly extending the service life and reliability of the material.

[0020] (4) Improve the mechanical properties and thermal stability of materials Modification with nanosilica and graphene nanosheets increases the mechanical strength, hardness, thermal conductivity, and impact resistance of the resin. The modification of nanosilica and oxidized and reduced graphene nanosheets involves combining their surfaces with aminopropyltriethoxysilane to produce hydroxyl-terminated silane-modified nanosilica and reduced graphene oxide nanosheets. These can participate in the polymerization reaction of polyurethane, forming a three-dimensional cross-linked network structure. This improves compatibility with the polyurethane matrix and effectively enhances the material's resistance to thermal aging. The graphene nanosheets, through their high electrical and thermal conductivity, improve the thermal stability of the resin, providing improved heat resistance and impact resistance. DETAILED DESCRIPTION

[0021] Example 1: S1. Accurately weigh the following ingredients: 100 parts of polypropylene glycol, 40 parts of diphenylmethane diisocyanate, 4 parts of nano-silica, 1 part of graphene nanosheets, 0.8 parts of UV absorber UV-327, 0.4 parts of antioxidant 1010, 6 parts of self-healing microcapsules, and 0.2 parts of catalyst dibutyltin dilaurate; S2. Preparation of modified nano-silica: Add 100 parts of isopropyl alcohol solvent and 4 parts of γ-aminopropyltriethoxysilane to a reaction container, stir evenly until completely dissolved, add 20 parts of deionized water and 1 part of ammonia water, stir and react at room temperature for 40 minutes, add 10 parts of nano-silica, stir and react at room temperature for 4 hours, centrifuge, wash with deionized water and dry to obtain hydroxyl-terminated silane-modified nano-silica; S3. Preparation of modified graphene nanosheets: 80 parts of sulfuric acid and 10 parts of graphene nanosheets were added to the reaction vessel, stirred under ice bath conditions, and 8 parts of potassium permanganate were slowly added to the solution. Stirring was continued in the ice bath, controlling the temperature not to exceed 20°C, and the reaction solution was gradually heated to 80°C by slowly adding deionized water. The temperature was maintained for 200 minutes, centrifuged, washed with sodium chloride solution, and graphene oxide was dispersed in 20 parts of deionized water. Ultrasonic dispersion was uniform, and ammonia was slowly added to adjust the pH to 9. The mixture was heated to 90°C and stirred for 200 minutes. Centrifuged, washed with deionized water and dried to obtain reduced graphene oxide nanosheets. 20 parts of isopropanol solvent and 2 parts of γ-aminopropyltriethoxysilane were added to the reaction vessel, ultrasonically dissolved and dispersed uniformly, and then the reduced graphene oxide nanosheets obtained previously were added. The reaction was stirred at room temperature for 100 minutes, centrifuged, washed with deionized water and dried to obtain hydroxyl-terminated silane-modified reduced graphene oxide nanosheets.

[0022] S4. Preparation of self-healing microcapsules: Add 60 parts of dichloromethane solvent and 10 parts of bisphenol A epoxy resin to a reaction vessel, disperse them evenly by ultrasonication to obtain an oil phase, add 60 parts of deionized water solvent, 11 parts of polyurethane resin, and 0.1 parts of surfactant hexadecyltrimethylammonium chloride to the reaction vessel to obtain an aqueous phase, mix the oil phase and the aqueous phase, emulsify them with a high-speed homogenizer to obtain uniform droplets, stir at a speed of 4000 rpm, and polymerize at 40°C for 4 hours. Remove the solvent by solvent evaporation, wash with deionized water, and dry to obtain self-healing microcapsules.

[0023] S5, adding the modified nano-silica and graphene into polypropylene glycol and uniformly dispersing them by ultrasonication; S6, adding ultraviolet absorber UV-327, antioxidant 1010 and self-healing microcapsules, and uniformly dispersing them by ultrasonication to form component A; S7, adding diphenylmethane diisocyanate as component B to component A, adding catalyst dibutyltin dilaurate, stirring and dispersing uniformly; S8. Curing at 70° C. for 100 minutes, followed by heat treatment at 100° C. for 50 minutes to obtain a highly durable polyurethane adhesive layer resin material.

[0024] Example 2: S1. Accurately weigh the following ingredients: 100 parts of polypropylene glycol, 42.5 parts of diphenylmethane diisocyanate, 4.5 parts of nano-silica, 1.5 parts of graphene nanosheets, 0.9 parts of UV absorber UV-327, 0.45 parts of antioxidant 1010, 7 parts of self-healing microcapsules, and 0.25 parts of catalyst dibutyltin dilaurate; S2. Preparation of modified nano-silica: 105 parts of isopropyl alcohol solvent and 4.5 parts of γ-aminopropyltriethoxysilane were added to a reaction vessel, stirred until completely dissolved, 22.5 parts of deionized water and 1.25 parts of ammonia water were added, stirred at room temperature for 45 minutes, 10 parts of nano-silica was added, stirred at room temperature for 4.5 hours, centrifuged, washed with deionized water and dried to obtain hydroxyl-terminated silane-modified nano-silica; S3. Preparation of modified graphene nanosheets: 90 parts of sulfuric acid and 10 parts of graphene nanosheets were added to the reaction vessel, stirred under ice bath conditions, and 9 parts of potassium permanganate were slowly added to the solution. Stirring was continued in an ice bath, controlling the temperature not to exceed 20°C, and the reaction solution was gradually heated to 85°C by slowly adding deionized water. The temperature was maintained for 210 minutes, centrifuged, washed with sodium chloride solution, and graphene oxide was dispersed in 25 parts of deionized water. Ultrasonic dispersion was uniform, and ammonia was slowly added to adjust the pH to 9.5. The mixture was heated to 95°C and stirred for 210 minutes. Centrifuged, washed with deionized water and dried to obtain reduced graphene oxide nanosheets. 25 parts of isopropanol solvent and 2.5 parts of γ-aminopropyltriethoxysilane were added to the reaction vessel, ultrasonically dissolved and dispersed uniformly, and then the reduced graphene oxide nanosheets obtained previously were added. The reaction was stirred at room temperature for 110 minutes, centrifuged, washed with deionized water and dried to obtain hydroxyl-terminated silane-modified reduced graphene oxide nanosheets.

[0025] S4. Preparation of self-healing microcapsules: Add 70 parts of dichloromethane solvent and 10 parts of bisphenol A epoxy resin to a reaction vessel, disperse them evenly by ultrasonication to obtain an oil phase, add 70 parts of deionized water solvent, 12 parts of polyurethane resin, and 0.2 parts of surfactant hexadecyltrimethylammonium chloride to the reaction vessel to obtain an aqueous phase, mix the oil phase and the aqueous phase, emulsify them with a high-speed homogenizer to obtain uniform droplets, stir at a speed of 5000 rpm, and polymerize at 50°C for 5 hours. Remove the solvent by solvent evaporation, wash with deionized water, and dry to obtain self-healing microcapsules.

[0026] S5, adding the modified nano-silica and graphene into polypropylene glycol and uniformly dispersing them by ultrasonication; S6, adding ultraviolet absorber UV-327, antioxidant 1010 and self-healing microcapsules, and uniformly dispersing them by ultrasonication to form component A; S7, adding diphenylmethane diisocyanate as component B to component A, adding catalyst dibutyltin dilaurate, stirring and dispersing uniformly; S8. Curing at 75° C. for 110 minutes, followed by heat treatment at 110° C. for 55 minutes to obtain a highly durable polyurethane adhesive layer resin material.

[0027] Example 3: S1. Accurately weigh the following ingredients: 100 parts of polypropylene glycol, 45 parts of diphenylmethane diisocyanate, 5 parts of nano-silica, 2 parts of graphene nanosheets, 1 part of UV absorber UV-327, 0.5 parts of antioxidant 1010, 8 parts of self-healing microcapsules, and 0.3 parts of catalyst dibutyltin dilaurate; S2. Preparation of modified nano-silica: 110 parts of isopropyl alcohol solvent and 5 parts of γ-aminopropyltriethoxysilane were added to a reaction vessel, stirred until completely dissolved, 25 parts of deionized water and 1.5 parts of ammonia water were added, stirred and reacted at room temperature for 50 minutes, 10 parts of nano-silica was added, stirred and reacted at room temperature for 5 hours, centrifuged, washed with deionized water and dried to obtain hydroxyl-terminated silane-modified nano-silica; S3. Preparation of modified graphene nanosheets: 100 parts of sulfuric acid and 10 parts of graphene nanosheets were added to the reaction vessel, stirred under ice bath conditions, and 10 parts of potassium permanganate were slowly added to the solution. Stirring was continued in the ice bath, controlling the temperature not to exceed 20°C, and the reaction solution was gradually heated to 90°C by slowly adding deionized water. The temperature was maintained for 220 minutes, centrifuged, washed with sodium chloride solution, and graphene oxide was dispersed in 30 parts of deionized water. Ultrasonic dispersion was uniform, and ammonia was slowly added to adjust the pH to 10. The mixture was heated to 100°C and stirred for 220 minutes. Centrifuged, washed with deionized water and dried to obtain reduced graphene oxide nanosheets. 30 parts of isopropanol solvent and 3 parts of γ-aminopropyltriethoxysilane were added to the reaction vessel, ultrasonically dissolved and dispersed uniformly, and then the reduced graphene oxide nanosheets obtained previously were added. The reaction was stirred at room temperature for 120 minutes, centrifuged, washed with deionized water and dried to obtain hydroxyl-terminated silane-modified reduced graphene oxide nanosheets.

[0028] S4. Preparation of self-healing microcapsules: Add 80 parts of dichloromethane solvent and 10 parts of bisphenol A epoxy resin to a reaction vessel, disperse them evenly by ultrasonication to obtain an oil phase, add 80 parts of deionized water solvent, 13 parts of polyurethane resin, and 0.3 parts of surfactant hexadecyltrimethylammonium chloride to the reaction vessel to obtain an aqueous phase, mix the oil phase and the aqueous phase, emulsify them with a high-speed homogenizer to obtain uniform droplets, stir at a speed of 6000 rpm, and polymerize at 60°C for 6 hours. Remove the solvent by solvent evaporation, wash with deionized water, and dry to obtain self-healing microcapsules.

[0029] S5, adding the modified nano-silica and graphene into polypropylene glycol and uniformly dispersing them by ultrasonication; S6, adding ultraviolet absorber UV-327, antioxidant 1010 and self-healing microcapsules, and uniformly dispersing them by ultrasonication to form component A; S7, adding diphenylmethane diisocyanate as component B to component A, adding catalyst dibutyltin dilaurate, stirring and dispersing uniformly; S8. Curing at 80° C. for 120 minutes, followed by heat treatment at 120° C. for 60 minutes to obtain a highly durable polyurethane adhesive layer resin material.

[0030] Example 4: S1. Accurately weigh the following ingredients: 100 parts of polypropylene glycol, 47.5 parts of diphenylmethane diisocyanate, 5.5 parts of nano-silica, 2.5 parts of graphene nanosheets, 1.1 parts of UV absorber UV-327, 0.55 parts of antioxidant 1010, 9 parts of self-healing microcapsules, and 0.35 parts of catalyst dibutyltin dilaurate; S2. Preparation of modified nano-silica: 115 parts of isopropyl alcohol solvent and 5.5 parts of γ-aminopropyltriethoxysilane were added to a reaction vessel, stirred until completely dissolved, 27.5 parts of deionized water and 1.75 parts of ammonia water were added, stirred at room temperature for 55 minutes, 10 parts of nano-silica was added, stirred at room temperature for 5.5 hours, centrifuged, washed with deionized water and dried to obtain hydroxyl-terminated silane-modified nano-silica; S3. Preparation of modified graphene nanosheets: 110 parts of sulfuric acid and 10 parts of graphene nanosheets were added to a reaction vessel, stirred under ice bath conditions, 11 parts of potassium permanganate were slowly added to the solution, and stirring was continued in the ice bath, the temperature was controlled not to exceed 20°C, and the reaction solution was gradually heated to 95°C by slowly adding deionized water, and the temperature was maintained for 230 minutes, centrifuged, washed with sodium chloride solution, and the graphene oxide was dispersed in 35 parts of deionized water, ultrasonically dispersed, and ammonia water was slowly added to adjust the pH. The reaction mixture was stirred to 10.5, heated to 105°C, reacted with stirring for 230 minutes, centrifuged, washed with deionized water and dried to obtain reduced graphene oxide nanosheets, 35 parts of isopropanol solvent and 3.5 parts of γ-aminopropyltriethoxysilane were added to the reaction vessel, ultrasonically dissolved and dispersed uniformly, and then the reduced graphene oxide nanosheets obtained previously were added, stirred at room temperature for 130 minutes, centrifuged, washed with deionized water and dried to obtain hydroxyl-terminated silane-modified reduced graphene oxide nanosheets.

[0031] S4. Preparation of self-healing microcapsules: Add 90 parts of dichloromethane solvent and 10 parts of bisphenol A epoxy resin to a reaction vessel, disperse them evenly by ultrasonication to obtain an oil phase, add 90 parts of deionized water solvent, 14 parts of polyurethane resin, and 0.4 parts of surfactant hexadecyltrimethylammonium chloride to the reaction vessel to obtain an aqueous phase, mix the oil phase and the aqueous phase, emulsify them with a high-speed homogenizer to obtain uniform droplets, stir at a speed of 7000 rpm, and polymerize at 70°C for 7 hours. Remove the solvent by solvent evaporation, wash with deionized water, and dry to obtain self-healing microcapsules.

[0032] S5, adding the modified nano-silica and graphene into polypropylene glycol and uniformly dispersing them by ultrasonication; S6, adding ultraviolet absorber UV-327, antioxidant 1010 and self-healing microcapsules, and uniformly dispersing them by ultrasonication to form component A; S7, adding diphenylmethane diisocyanate as component B to component A, adding catalyst dibutyltin dilaurate, stirring and dispersing uniformly; S8. Curing at 85° C. for 130 minutes, followed by heat treatment at 130° C. for 65 minutes to obtain a highly durable polyurethane adhesive layer resin material.

[0033] Example 5: S1. Accurately weigh the following ingredients: 100 parts of polypropylene glycol, 50 parts of diphenylmethane diisocyanate, 6 parts of nano-silica, 3 parts of graphene nanosheets, 1.2 parts of UV absorber UV-327, 0.6 parts of antioxidant 1010, 10 parts of self-healing microcapsules, and 0.4 parts of catalyst dibutyltin dilaurate; S2. Preparation of modified nano-silica: Add 120 parts of isopropyl alcohol solvent and 6 parts of γ-aminopropyltriethoxysilane to a reaction container, stir evenly until completely dissolved, add 30 parts of deionized water and 2 parts of ammonia water, stir and react at room temperature for 60 minutes, add 10 parts of nano-silica, stir and react at room temperature for 6 hours, centrifuge, wash with deionized water and dry to obtain hydroxyl-terminated silane-modified nano-silica; S3. Preparation of modified graphene nanosheets: 120 parts of sulfuric acid and 10 parts of graphene nanosheets were added to the reaction vessel, stirred under ice bath conditions, and 12 parts of potassium permanganate were slowly added to the solution. Stirring was continued in the ice bath, controlling the temperature to no more than 20°C, and the reaction solution was gradually heated to 100°C by slowly adding deionized water. The temperature was maintained for 240 minutes, centrifuged, washed with sodium chloride solution, and graphene oxide was dispersed in 40 parts of deionized water. Ultrasonic dispersion was uniformly performed, and ammonia was slowly added to adjust the pH to 11. The mixture was heated to 110°C and stirred for 240 minutes. Centrifuged, washed with deionized water and dried to obtain reduced graphene oxide nanosheets. 40 parts of isopropanol solvent and 4 parts of γ-aminopropyltriethoxysilane were added to the reaction vessel, ultrasonically dissolved and dispersed uniformly, and then the reduced graphene oxide nanosheets obtained previously were added. The reaction was stirred at room temperature for 140 minutes, centrifuged, washed with deionized water and dried to obtain hydroxyl-terminated silane-modified reduced graphene oxide nanosheets.

[0034] S4. Preparation of self-healing microcapsules: Add 100 parts of dichloromethane solvent and 10 parts of bisphenol A epoxy resin to a reaction vessel, disperse them evenly by ultrasonication to obtain an oil phase, add 100 parts of deionized water solvent, 15 parts of polyurethane resin, and 0.5 parts of surfactant hexadecyltrimethylammonium chloride to the reaction vessel to obtain an aqueous phase, mix the oil phase and the aqueous phase, emulsify them with a high-speed homogenizer to obtain uniform droplets, stir at a speed of 8000 rpm, and polymerize at 80°C for 8 hours. Remove the solvent by solvent evaporation, wash with deionized water, and dry to obtain self-healing microcapsules.

[0035] S5, adding the modified nano-silica and graphene into polypropylene glycol and uniformly dispersing them by ultrasonication; S6, adding ultraviolet absorber UV-327, antioxidant 1010 and self-healing microcapsules, and uniformly dispersing them by ultrasonication to form component A; S7, adding diphenylmethane diisocyanate as component B to component A, adding catalyst dibutyltin dilaurate, stirring and dispersing uniformly; S8. Curing at 90° C. for 140 minutes, followed by heat treatment at 140° C. for 70 minutes to obtain a highly durable polyurethane adhesive layer resin material.

[0036] Performance Testing Mechanical properties testing The high-durability polyurethane adhesive layer resin material obtained in Examples 1-5 was cut into standard-sized samples, measuring 50×10×2 cm. The mechanical properties of the samples were tested using an Instron 3367 electronic universal material testing machine at a temperature of 25°C and a tensile rate of 10 mm / min. The following table shows the test results: Heat resistance test A 10g sample of the high-durability polyurethane adhesive layer resin material obtained in Examples 1-5 was cut and its heat resistance was tested using a NETZSCHTG 209F1 Libra thermogravimetric analyzer in a nitrogen atmosphere at a temperature range of 25-800°C and a heating rate of 10°C / min. The following table shows the test results: UV resistance test The highly durable polyurethane adhesive layer resin materials obtained in Examples 1-5 were cut into standard-sized samples, measuring 50 × 10 × 2 cm. Their UV resistance was tested using a Q-Lab QUV UV aging test chamber, using a UV-A340 light source for 96 hours, a spray cycle of 4 hours of light and 4 hours of condensation, and exposure to the sun for the set time. The color change was then observed, and the tensile strength was tested using an Instron 3367 electronic universal material testing machine. The test results are shown in the following table: Self-healing performance test The high-durability polyurethane adhesive layer resin material obtained in Examples 1-5 was cut into standard-sized samples, measuring 50×10×2 cm. A 100 μm-wide scratch was made using a needle tip and placed in a 50°C constant-temperature oven for 12 hours. The scratch repair was then observed and the tensile strength was tested using an Instron 3367 electronic universal material testing machine. The test results are shown in the following table: Bond strength test The highly durable polyurethane adhesive layer resin material obtained in Examples 1-5 was bonded to a polished and cleaned aluminum sheet. The bonding area was standardized to 25 mm × 20 mm, and the bonding thickness was controlled to 1 mm. The bonding strength was tested using an Instron peel test fixture and an Instron 3367 electronic universal material testing machine. The temperature was room temperature, the humidity was 50%, the peel speed was 100 mm / min, and the shear tensile speed was 5 mm / min. The test results are shown in the following table:

Claims

1. A highly durable polyurethane adhesive layer resin material, characterized in that: The materials described include the following in parts by mass: (1) Polyether polyol, 100 parts; (2) Isocyanate, 40-50 parts; (3) Nano-silicon dioxide, 4-6 parts, the nano-silicon dioxide has a particle size of 20-60 nm and needs to be chemically modified; (4) 1-3 parts of graphene nanosheets, wherein the graphene nanosheets need to be chemically modified; (5) UV absorber, 0.8-1.2 parts; (6) Antioxidant, 0.4-0.6 parts; (7) Self-healing microcapsules, 6-10 parts, wherein the core material of the self-healing microcapsules is bisphenol A epoxy resin and the wall material is polyurethane resin; (8) Catalyst, 0.2-0.4 parts.

2. The highly durable polyurethane adhesive layer resin material according to claim 1, characterized in that: The polyether polyol is polypropylene glycol with a molecular weight of 2000.

3. The highly durable polyurethane adhesive layer resin material according to claim 1, characterized in that: The isocyanate is diphenylmethane diisocyanate.

4. The highly durable polyurethane adhesive layer resin material according to claim 1, characterized in that: The modification steps of the nano-silica are as follows: adding isopropyl alcohol solvent and γ-aminopropyltriethoxysilane to a reaction container, stirring evenly until completely dissolved, adding deionized water and ammonia water, stirring and reacting at room temperature for 40-60 minutes, adding nano-silica in a mass ratio of 100-120 parts: 4-6 parts: 20-30 parts: 1-2 parts: 10 parts, stirring and reacting at room temperature for 4-6 hours, centrifuging, washing with deionized water and drying to obtain hydroxyl-terminated silane-modified nano-silica.

5. The highly durable polyurethane adhesive layer resin material according to claim 1, characterized in that: The modification steps of the graphene nanosheets are as follows: adding sulfuric acid and graphene nanosheets to a reaction container, stirring under ice bath conditions, slowly adding potassium permanganate to the solution, continuing to stir in the ice bath, controlling the temperature not to exceed 20° C., slowly adding deionized water to control the reaction solution to gradually heat up to 80-100° C., maintaining the temperature for 200-240 minutes, centrifuging, washing with sodium chloride solution, dispersing graphene oxide in deionized water, ultrasonically dispersing it uniformly, slowly adding ammonia water, adjusting the pH value to 9-11, heating to 90-110° C., stirring the reaction for 200-240 minutes. The reaction mixture was stirred for 240 minutes, centrifuged, washed with deionized water and dried to obtain reduced graphene oxide nanosheets. Isopropyl alcohol solvent and γ-aminopropyltriethoxysilane were added to the reaction vessel in a mass ratio of 80-120 parts: 10 parts: 8-12 parts: 20-40 parts: 20-40 parts: 2-4 parts. The mixture was ultrasonically dissolved and dispersed uniformly. The reduced graphene oxide nanosheets obtained above were then added. The reaction was stirred at room temperature for 100-140 minutes, centrifuged, washed with deionized water and dried to obtain hydroxyl-terminated silane-modified reduced graphene oxide nanosheets.

6. The highly durable polyurethane adhesive layer resin material according to claim 1, characterized in that: The ultraviolet absorber is ultraviolet absorber UV-327.

7. The highly durable polyurethane adhesive layer resin material according to claim 1, characterized in that: The antioxidant is antioxidant 1010.

8. The highly durable polyurethane adhesive layer resin material according to claim 1, characterized in that: The preparation method of the self-healing microcapsules is as follows: adding dichloromethane solvent and bisphenol A epoxy resin to a reaction container, ultrasonically dispersing them uniformly to obtain an oil phase, adding deionized water solvent, polyurethane resin, and surfactant cetyltrimethylammonium chloride to the reaction container to obtain an aqueous phase, wherein the weight ratio of the five is 60-100 parts:10 parts:60-100 parts:11-15 parts:0.1-0.5 parts, mixing the oil phase and the aqueous phase, emulsifying them with a high-speed homogenizer to obtain uniform droplets, stirring at a speed of 4000-8000 rpm, polymerizing at 40-80°C for 4-8 hours, removing the solvent by solvent evaporation, washing with deionized water, and drying to obtain self-healing microcapsules.

9. The highly durable polyurethane adhesive layer resin material according to claim 1, characterized in that: The catalyst is dibutyltin dilaurate.

10. The highly durable polyurethane adhesive layer resin material according to claim 1, characterized in that: The preparation method comprises the following steps: S1. Accurately weighing the ingredients, modifying nano-silica and graphene nanosheets, and preparing self-healing microcapsules; S2, adding the modified nano-silica and graphene to the polyether polyol and uniformly dispersing them by ultrasonication; S3, adding ultraviolet absorber, antioxidant and self-healing microcapsules, and uniformly dispersing them by ultrasonication to form component A; S4, adding diphenylmethane diisocyanate as component B to component A, adding a catalyst, and stirring to disperse uniformly; S5. Curing at 70-90° C. for 100-140 minutes, followed by heat treatment at 100-140° C. for 50-70 minutes to obtain a highly durable polyurethane adhesive layer resin material.

Images