Self-repairing optical adhesive film, preparation method and application thereof

Abstract

This invention discloses a self-healing optical film, its preparation method, and its application. The self-healing optical film is prepared by a stepwise photocuring process using an adhesive solution. The adhesive solution contains a polyurethane acrylate oligomer with dynamic covalent bonds, an acrylate monomer containing four hydrogen bond units, an active diluent, a first photoinitiator, and a second photoinitiator. The dynamic covalent bonds are disulfide bonds and borate ester bonds, and the association constant of the four hydrogen bond units is [value missing]. This invention achieves functional decoupling and spatial synergy of a dual dynamic repair network through stepwise construction. The hydrogen bond physical network is responsible for rapidly closing microcracks at room temperature, while the dynamic covalent chemical network gradually restores material strength through disulfide bond exchange and dynamic recombination of borate ester bonds. This achieves a balance between efficient self-healing at room temperature and excellent mechanical properties, overcoming the technical challenge of traditional self-healing materials where strength and repair efficiency cannot be simultaneously achieved.

Description

Technical Field

[0001] This invention relates to the field of membrane materials technology, and in particular to a self-healing optical film, its preparation method, and its application. Background Technology

[0002] Currently, self-healing technologies in the field of optical films are mainly divided into microcapsule type, thermally reversible covalent type, and hydrogen bond or metal coordination non-covalent type. However, microcapsule type achieves damage release by encapsulating the repair agent, but the capsule particles affect the light transmittance and the number of repairs is limited; thermally reversible covalent type (such as Diels-Alder reaction, disulfide bond exchange) requires external heating for activation, has a slow response, and requires a high repair temperature; although hydrogen bond or metal coordination non-covalent type can achieve room temperature repair, it has low mechanical strength and poor resistance to damp heat. Summary of the Invention

[0003] This invention provides a self-healing optical film, its preparation method, and its application, in order to solve the technical problem of poor repair performance of current optical films.

[0004] In a first aspect, the present invention provides a self-healing optical adhesive film, prepared from an adhesive liquid via a graded photocuring process, wherein the adhesive liquid comprises the following components in parts by mass: 40 to 80 parts of polyurethane acrylate oligomer containing dynamic covalent bonds; 10 to 40 parts of acrylate monomers containing four hydrogen bond units; 5 to 30 parts of reactive diluent Photoinitiator 0.5 to 5 parts; The dynamic covalent bonds are disulfide bonds and borate ester bonds, and the association constant of the quadruple hydrogen bond unit is Ka≥10. 5 The photoinitiator includes a first photoinitiator with a main absorption peak located at 350 nm to 370 nm and a second photoinitiator with a main absorption peak located at 380 nm to 400 nm.

[0005] In some embodiments, the graded photocuring process includes: An LED-UV light source with a wavelength of 365nm±5nm was used, with an irradiation dose of 500 mJ / cm²±50 mJ / cm², a curing temperature of 25℃±2℃, and a curing time of 20s~40s, so that the acrylate monomers containing quadruple hydrogen bond units could form a hydrogen bond physical network. Allow a 30-60 second interval to allow the hydrogen bond physical network to fully form; An LED-UV light source with a wavelength of 395nm±5nm was used, and the irradiation dose was 1500mJ / cm². 2 ±100 mJ / cm 2The curing temperature is 25℃±2℃ and the curing time is 60s~90s, which cross-links and polymerizes the polyurethane acrylate oligomers containing dynamic covalent bonds to form a dynamic covalent chemical network.

[0006] In some embodiments, the number-average molecular weight of the polyurethane acrylate oligomer is 10,000 to 30,000, and the molecular weight distribution index (PDI) is ≤2, to ensure that the oligomer has suitable flowability and reactivity, forms a uniform adhesive layer during coating, and has a moderate crosslinking density after curing, avoiding excessively high molecular weight leading to high viscosity and difficulty in coating, or excessively low molecular weight leading to insufficient mechanical properties.

[0007] In some embodiments, the method for preparing the polyurethane acrylate oligomer containing dynamic covalent bonds includes the following steps: Excess isophorone diisocyanate was mixed with polytetrahydrofuran diol and heated and stirred at 70±2℃ and 200rpm~400rpm for 2h under nitrogen protection to obtain isocyanate-terminated prepolymer. The prepolymer was mixed with 3-hydroxyphenylboronic acid and heated and stirred at 60℃±2℃ and 200rpm~400rpm for 1h under nitrogen protection. Then, bis(2-hydroxyethyl) disulfide and dibutyltin dilaurate were added, and the mixture was heated and stirred for another 30min. The amount of bis(2-hydroxyethyl) disulfide was 5%~15% of the mass of the prepolymer, the amount of 3-hydroxyphenylboronic acid was 3%~10% of the mass of the prepolymer, and the amount of dibutyltin dilaurate was 0.01%~0.05% of the mass of the prepolymer. Hydroxyethyl methacrylate was added to the reaction system, and the mixture was heated and stirred until the absorption peak of the isocyanate group disappeared as monitored by infrared spectroscopy, thus obtaining a polyurethane acrylate oligomer containing disulfide bonds and borate ester bonds. In some embodiments, the quadruple hydrogen bond unit is a ureidinidone unit, and the association constant is... This improves the association strength of the hydrogen bond network, reduces the repair speed from hours to minutes, and lowers the haze after repair.

[0008] In some embodiments, the method for preparing the acrylate monomer containing four hydrogen bond units includes the following steps: 2-Amino-4-hydroxy-6-methylpyrimidine and methacryloyloxyethyl isocyanate were mixed in an anhydrous solvent at a molar ratio of 1:1.1. The mixture was heated and stirred at 50℃±2℃ and 100rpm~300rpm for 4h under nitrogen protection. After the reaction was completed, the reaction solution was dropped into n-hexane to precipitate the precipitate. The precipitate was filtered and dried under vacuum at 40℃±2℃ to constant weight to obtain an acrylate monomer containing four hydrogen bond units.

[0009] In some embodiments, the reactive diluent comprises ethoxyethoxyethyl acrylate and isobornyl acrylate in a mass ratio of 1:(0.5~2), EOEOEA provides flexible segments to reduce the viscosity of the system, and IBOA adjusts Tg to increase the modulus; Alternatively, the first photoinitiator may include 2,2-dimethoxy-2-phenylacetophenone or 1-hydroxycyclohexylphenyl ketone, and the second photoinitiator may include diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide or bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide.

[0010] In some embodiments, a nano-reinforcing phase is also included, which is one or more of cellulose nanocrystals, silica nanoparticles, and graphene quantum dots with non-covalent hydrogen bond units or dynamic covalent bond units grafted on the surface. The hydrogen bonding between the nanoparticles and the matrix can form additional energy dissipation channels, enabling multiple dynamic foldings without performance degradation.

[0011] Secondly, the present invention provides a method for preparing a self-healing optical adhesive film, comprising the following steps: Polyurethane acrylate oligomers containing dynamic covalent bonds, acrylate monomers containing four hydrogen bond units, and reactive diluents were mixed and heated and stirred at 50℃±2℃ and 300rpm~500rpm for 1h. The mixture was then cooled to 25℃±2℃, a photoinitiator was added, and the mixture was stirred at 200rpm~400rpm in the dark for 30min. Finally, the mixture was degassed under a vacuum of -0.08MPa to -0.1MPa for 30min to obtain the adhesive solution. The adhesive is applied to the release film and cured using a graded light curing process. After curing, a second release film is bonded on and subjected to a aging process to obtain a self-healing optical adhesive film.

[0012] Thirdly, the present invention provides an application of a self-healing optical adhesive film in the bonding of display modules and / or optical modules.

[0013] Compared with the prior art, the present invention has the following beneficial effects: This invention utilizes a stepwise photocuring process with a first and a second photoinitiator to preferentially polymerize acrylate monomers containing quadruple hydrogen bonds (monofunctional, resulting in faster polymerization rates). The intermolecular quadruple hydrogen bonds self-assemble to form a reversible hydrogen bond physical network, endowing the material with rapid self-healing properties at room temperature. Subsequently, polyurethane acrylate oligomers containing disulfide and borate ester bonds undergo cross-linking polymerization to form a dynamic covalent chemical network, providing mechanical strength and reversible cross-linking capability. An active diluent adjusts the system's viscosity and flexibility. This stepwise construction achieves functional decoupling and spatial synergy of the dual dynamic repair networks. The hydrogen bond physical network is responsible for rapidly closing microcracks at room temperature, while the dynamic covalent chemical network gradually restores material strength through disulfide bond exchange and dynamic recombination of borate ester bonds. This balance between efficient room-temperature self-healing and excellent mechanical properties overcomes the technical challenge of traditional self-healing materials where strength and repair efficiency are mutually exclusive. Detailed Implementation

[0014] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described in detail below. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0015] As used herein, the terms “prepared from” and “comprising” are synonymous. The terms “comprising,” “including,” “having,” “containing,” or any other variations thereof, as used herein, are intended to cover non-exclusive inclusion. For example, a composition, step, method, article, or apparatus that includes the listed elements is not necessarily limited to those elements, but may include other elements not expressly listed or elements inherent to such composition, step, method, article, or apparatus.

[0016] When a quantity, concentration, or other value or parameter is expressed as a range, a preferred range, or a range defined by a series of upper and lower preferred values, it should be understood as specifically disclosing all ranges formed by any pair of any upper or preferred value with any lower or preferred value, regardless of whether the range is disclosed individually.

[0017] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. Unless otherwise specified, the raw materials used in the following examples and comparative examples are commercially available industrial products, and all conditions not otherwise specified are conventional.

[0018] Preparation Example 1: Synthesis of polyurethane acrylate oligomers (PUA-DB) containing disulfide bonds and borate ester bonds Under nitrogen protection, 222 g (1.0 mol) of isophorone diisocyanate, 400 g (0.2 mol) of polytetrahydrofuran diol (Mn=2000) and 0.15 g of dibutyltin dilaurate were added to a 2 L four-necked flask equipped with a mechanical stirrer, thermometer and reflux condenser. The mixture was stirred at 70±2 °C for 2 h to obtain an isocyanate-terminated prepolymer. Add 3-hydroxyphenylboronic acid (5% of the prepolymer mass, i.e., 31.1 g) to the above prepolymer and continue stirring at 60±2℃ for 1 h; then add bis(2-hydroxyethyl) disulfide (10% of the prepolymer mass) and dibutyltin dilaurate (0.03% of the prepolymer mass), and continue stirring at 60±2℃ for 30 minutes; finally add 52 g of hydroxyethyl methacrylate for end capping, and react at 60±2℃ until infrared spectroscopy monitoring is performed. The absorption peak of the isocyanate group completely disappeared, yielding PUA-DB. GPC determination: Mn=18500, PDI=1.86.

[0019] Preparation Example 2: Synthesis of Ureidinidone Methacrylate (UPy-MA) Under nitrogen protection, 125 g (1.0 mol) of 2-amino-4-hydroxy-6-methylpyrimidine and 500 mL of anhydrous chloroform were added to a 1 L four-necked flask equipped with a mechanical stirrer, thermometer, and constant-pressure dropping funnel. The mixture was stirred and dissolved at 50 ± 2 °C. 170 g (1.1 mol) of methacryloyloxyethyl isocyanate was slowly added dropwise through the constant-pressure dropping funnel, controlling the dropping rate to keep the reaction temperature below 55 °C for about 1 hour. After the addition was complete, the mixture was stirred and reacted for another 4 hours at 50 ± 2 °C. After the reaction was complete, the reaction solution was cooled to room temperature and slowly added dropwise to 5 L of n-hexane to precipitate the product. The precipitate was filtered, washed three times with n-hexane, and dried under vacuum at 40 ± 2 °C to constant weight, yielding a white powder UPy-MA with a yield of 92% and a purity of ≥98% as determined by HPLC.

[0020] Preparation Example 3: Preparation of UPy-grafted cellulose nanocrystals (UPy-CNC) 10 g of cellulose nanocrystals were dispersed in 200 mL of anhydrous DMF and ultrasonically dispersed for 30 min (power 200 W). 3 g of isophorone diisocyanate and 0.05 g of dibutyltin dilaurate were added, and the mixture was stirred at 60 °C for 2 h to introduce isocyanate groups. The mixture was centrifuged, and washed three times with DMF to remove unreacted isophorone diisocyanate. The resulting product was redispersed in 200 mL of anhydrous DMF, and 5 g of UPy-MA (prepared in Preparation Example 2) was added. The mixture was stirred at 60 °C for 4 h. After the reaction was completed, the mixture was centrifuged, washed successively with DMF, ethanol, and deionized water, and dried under vacuum at 60 °C to constant weight to obtain UPy-CNC. The grafting rate was determined to be approximately 8% by thermogravimetric analysis. Example 1

[0021] Take 40g of PUA-DB prepared in Preparation Example 1, 10g of UPy-MA prepared in Preparation Example 2, 4g of EOEOEA, and 2g of IBOA, add them to a mixing tank, stir at 50±2℃ and 400rpm for 1h, then cool to 25±2℃, add 0.2g of 2,2-dimethoxy-2-phenylacetophenone (DMPA) and 0.3g of diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (TPO), stir at 200rpm for 30min in the dark; transfer the adhesive solution to a vacuum degassing kettle, degas at a vacuum of -0.09MPa for 30min to obtain the adhesive solution; A comma-shaped doctor blade coater is used to apply the adhesive to a PET release film (75μm thick), with the coating thickness controlled at 75μm. A graded photocuring process is employed. First stage curing: LED-UV light source, wavelength 365nm, irradiation dose 500mJ / cm², curing temperature 25℃, curing time 20s; 30-second interval; Second stage curing: LED-UV light source, wavelength 395nm, irradiation dose 1500mJ / cm², curing temperature 25℃, curing time 90s; After curing, a PET light release film (50μm thick) is laminated and aged at 40℃ and 45%RH for 24h to obtain a self-healing optical film. Example 2

[0022] The difference from Example 1 is that the adhesive formulation of Example 2 is adjusted to: PUA-DB 58g, UPy-MA 25g, EOEOEA 10g, IBOA 8g, DMPA 1g, TPO 2g; the graded light curing process is adjusted to: the first stage curing time is 20s with an interval of 45s, the second stage curing time is 75s, and other conditions are the same as in Example 1. Example 3

[0023] The difference from Example 2 is that the adhesive formulation of Example 3 also contains 2g of UPy-CNC. Example 4

[0024] The difference from Example 1 is that the adhesive formulation of Example 4 is adjusted to: PUA-DB 80g, UPy-MA 40g, EOEOEA 10g, IBOA 20g; Irgacure 184 2g, Irgacure 819 3g; the graded light curing process is adjusted to: the first stage curing time is 40s, with an interval of 60s, and the second stage curing time is 60s, and other conditions are the same as in Example 1.

[0025] Comparative Example 1 The difference from Example 1 is that Comparative Example 1 uses a one-step curing process instead of a graded light curing process: a 395nm LED-UV light source is used, the single irradiation dose is 2000mJ / cm² (equivalent to the simultaneous action of 365nm and 395nm), and the curing time is 105s.

[0026] Comparative Example 2 The difference from Example 1 is that Comparative Example 2 uses only 0.5g of TPO as a photoinitiator.

[0027] Comparative Example 3 The difference from Example 1 is that Comparative Example 3 uses PUA-DB instead of UPy-MA.

[0028] Comparative Example 4 The difference from Example 1 is that Comparative Example 4 uses UPy-MA instead of PUA-DB.

[0029] Comparative Example 5 The difference from Example 1 is that Comparative Example 5 uses a polyurethane acrylate oligomer (PUA-SS) containing only disulfide bonds instead of PUA-DB, and synthesizes PUA-SS according to the method of Preparation Example 1. The difference is that 3-hydroxyphenylboronic acid is not added, while the other conditions are the same.

[0030] Comparative Example 6 The difference from Example 1 is that Comparative Example 6 uses a polyurethane acrylate oligomer (PUA-BE) containing only borate ester bonds instead of PUA-DB, and synthesizes PUA-SS according to the method of Preparation Example 1. The difference is that bis(2-hydroxyethyl) disulfide is not added, and the other conditions are the same.

[0031] Comparative Example 7 The difference from Example 1 is that Comparative Example 7 uses acrylic acid (carboxyl hydrogen bond association constant = 10). 3 ) replaces UPy-MA.

[0032] Comparative Example 8 The difference from Example 1 is that the graded photocuring process of Comparative Example 8 eliminates the interval period.

[0033] Performance testing 1. Mechanical repair efficiency: Cut the adhesive film into dumbbell-shaped strips (ISO 37-2 type), and test the original tensile strength using a universal testing machine; cut the middle of the strip with a blade, make close contact between the cut surfaces, repair at 25℃ for 30 minutes, and test the tensile strength again. Repair efficiency = repaired strength / original strength × 100%.

[0034] 2. Transmittance and haze: According to GB / T 2410-2008, the transmittance and haze were tested using a WGT-S transmittance and haze meter, with a sample size of 50mm×50mm.

[0035] 3. Number of repairs: Repeat the "cut-repair-test" cycle until the repair efficiency is below 90%, and record the number of cycles.

[0036] 4. Dynamic folding test: The adhesive film is bonded between two 50μm PI films to make a 10cm×5cm sample. The sample is folded 200,000 times using a folding tester (curvature radius 3mm, frequency 30 times / min) to observe the creases and delamination.

[0037] Table 1. Repair performance test results of the examples and comparative examples.

[0038] As shown in Table 1, Examples 1 to 4, through a graded photopolymerization process, constructed a dual network structure with dynamic covalent bonds and quadruple hydrogen bonds, achieving excellent optical performance with a repair efficiency of over 95% at room temperature after 30 minutes, a light transmittance of over 99% after repair, and a haze of less than 0.35%. The repair cycle exceeded 45 times, with a tensile strength of over 11 MPa, an elongation at break greater than 270%, and no creases after 200,000 dynamic folds. Compared to Example 2, Example 3 showed improved performance after the addition of UPy-CNC. Compared to Example 1, Comparative Example 1 lacks a graded curing process. UPy-MA and PUA-DB are simultaneously polymerized and crosslinked, failing to form a regular hydrogen bond physical network. Hydrogen bond units are randomly distributed in the covalent network, unable to effectively self-assemble to drive crack closure. Repair relies solely on the slow exchange of dynamic covalent bonds, resulting in a significant decrease in repair efficiency and the number of repairable times, leading to severe cracking after folding.

[0039] Comparative Example 2 uses a single initiator. TPO still absorbs at the 365nm stage. During UPy-MA polymerization, PUA-DB undergoes partial cross-linking, and the regularity of the hydrogen bond network is destroyed. During the second stage of curing, there is insufficient residual UPy-MA, and the hydrogen bond network density is low, resulting in a significant decrease in repair efficiency and the number of repairable times, and an increase in haze.

[0040] Comparative Example 3 lacks UPy-MA, has no hydrogen bond physical network, and has an extremely slow exchange rate of disulfide bonds and borate ester bonds at room temperature, resulting in a significant decrease in repair efficiency and the number of repairable times, and an increase in material brittleness.

[0041] Comparative Example 4 lacks PUA-DB and relies solely on physical cross-linking via hydrogen bonds, resulting in a significant decrease in tensile strength. It cannot be used as a structural adhesive and exhibits severe deformation and creep after folding, rendering it useless.

[0042] Comparative Example 5 lacks boronic ester bonds for synergistic repair, and disulfide bond exchange requires free radical triggering, which has limited efficiency at room temperature, resulting in a significant decrease in repair efficiency and the number of repair cycles. The single dynamic bond gradually becomes inactive after repeated exchange.

[0043] Comparative Example 6 lacks disulfide bond coordination, and the borate ester bond requires moisture for activation. Exchange is slow under dry conditions, resulting in a decrease in repair efficiency and the number of repair cycles. Hydrolysis byproducts lead to an increase in haze.

[0044] Comparative Example 7 used carboxyl groups to replace UPy, resulting in insufficient hydrogen bond network strength, which led to a significant decrease in repair efficiency and the number of repairable times; the carboxyl groups were incompatible with the system, resulting in a haze as high as 1.58%.

[0045] In Comparative Example 8, the polymerization of UPy-MA was interrupted by the second-stage curing before it could fully self-assemble. The low density and poor regularity of the hydrogen bond network resulted in a decrease in repair efficiency and the number of repairable times.

[0046] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0047] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. In particular, it should be noted that any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention for those skilled in the art.

Claims

1. A self-healing optical film, characterized in that, It is prepared by a graded photocuring process from an adhesive solution, wherein the adhesive solution comprises the following components in parts by mass: 40 to 80 parts of polyurethane acrylate oligomer containing dynamic covalent bonds; 10 to 40 parts of acrylate monomers containing four hydrogen bond units; 5 to 30 parts of reactive diluent Photoinitiator 0.5 to 5 parts; The dynamic covalent bonds are disulfide bonds and borate ester bonds, and the association constant of the quadruple hydrogen bond unit is Ka≥10. 5 The photoinitiator includes a first photoinitiator with a main absorption peak located at 350 nm to 370 nm and a second photoinitiator with a main absorption peak located at 380 nm to 400 nm.

2. The self-healing optical film as described in claim 1, characterized in that, The graded photocuring process includes: An LED-UV light source with a wavelength of 365nm±5nm was used, with an irradiation dose of 500 mJ / cm²±50 mJ / cm², a curing temperature of 25℃±2℃, and a curing time of 20s~40s, so that the acrylate monomers containing quadruple hydrogen bond units could form a hydrogen bond physical network. Allow a 30-60 second interval to allow the hydrogen bond physical network to fully form; An LED-UV light source with a wavelength of 395nm±5nm was used, and the irradiation dose was 1500mJ / cm². 2 ±100 mJ / cm 2 The curing temperature is 25℃±2℃ and the curing time is 60s~90s, which cross-links and polymerizes the polyurethane acrylate oligomers containing dynamic covalent bonds to form a dynamic covalent chemical network.

3. The self-healing optical film as described in claim 1, characterized in that, The number-average molecular weight of the polyurethane acrylate oligomer is 10,000 to 30,000, and the molecular weight distribution index (PDI) is ≤2.

4. The self-healing optical film as described in claim 3, characterized in that, The preparation method of the polyurethane acrylate oligomer containing dynamic covalent bonds includes the following steps: Excess isophorone diisocyanate was mixed with polytetrahydrofuran diol and heated and stirred at 70±2℃ and 200rpm~400rpm for 2h under nitrogen protection to obtain isocyanate-terminated prepolymer. The prepolymer was mixed with 3-hydroxyphenylboronic acid and heated and stirred at 60℃±2℃ and 200rpm~400rpm for 1h under nitrogen protection. Then, bis(2-hydroxyethyl) disulfide and dibutyltin dilaurate were added, and the mixture was heated and stirred for another 30min. The amount of bis(2-hydroxyethyl) disulfide was 5%~15% of the mass of the prepolymer, the amount of 3-hydroxyphenylboronic acid was 3%~10% of the mass of the prepolymer, and the amount of dibutyltin dilaurate was 0.01%~0.05% of the mass of the prepolymer. Hydroxyethyl methacrylate was added to the reaction system, and the mixture was heated and stirred until the absorption peak of the isocyanate group disappeared as monitored by infrared spectroscopy, thus obtaining a polyurethane acrylate oligomer containing disulfide bonds and borate ester bonds.

5. The self-healing optical film as described in claim 1, characterized in that, The quadruple hydrogen bond unit is a ureidopyrimidinone unit, and the association constant is... .

6. The self-healing optical film as described in claim 5, characterized in that, The method for preparing the acrylate monomer containing four hydrogen bond units includes the following steps: 2-Amino-4-hydroxy-6-methylpyrimidine and methacryloyloxyethyl isocyanate were mixed in an anhydrous solvent at a molar ratio of 1:1.

1. The mixture was heated and stirred at 50℃±2℃ and 100rpm~300rpm for 4h under nitrogen protection. After the reaction was completed, the reaction solution was dropped into n-hexane to precipitate the precipitate. The precipitate was filtered and dried under vacuum at 40℃±2℃ to constant weight to obtain an acrylate monomer containing four hydrogen bond units.

7. The self-healing optical film as described in claim 1, characterized in that, The reactive diluent comprises ethoxyethoxyethyl acrylate and isobornyl acrylate in a mass ratio of 1:(0.5~2); Alternatively, the first photoinitiator may include 2,2-dimethoxy-2-phenylacetophenone or 1-hydroxycyclohexylphenyl ketone, and the second photoinitiator may include diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide or bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide.

8. The self-healing optical film as described in claim 1, characterized in that, It also includes a nano-reinforcing phase, which is one or more of cellulose nanocrystals, silica nanoparticles, and graphene quantum dots with non-covalent hydrogen bond units or dynamic covalent bond units grafted on their surface.

9. A method for preparing a self-healing optical film as described in any one of claims 1 to 8, characterized in that, Includes the following steps: Polyurethane acrylate oligomers containing dynamic covalent bonds, acrylate monomers containing four hydrogen bond units, and reactive diluents were mixed and heated and stirred at 50℃±2℃ and 300rpm~500rpm for 1h. The mixture was then cooled to 25℃±2℃, a photoinitiator was added, and the mixture was stirred at 200rpm~400rpm in the dark for 30min. Finally, the mixture was degassed under a vacuum of -0.08MPa to -0.1MPa for 30min to obtain the adhesive solution. The adhesive is applied to the release film and cured using a graded light curing process. After curing, a second release film is bonded on and subjected to a aging process to obtain a self-healing optical adhesive film.

10. The application of a self-healing optical film as described in any one of claims 1 to 8 in the bonding of display modules and / or optical modules.

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