Efficient self-repairing vehicle-mounted OCA adhesive, preparation method thereof and adhesive film

Abstract

The invention discloses an efficient self-repairing vehicle-mounted OCA adhesive, a preparation method thereof and an adhesive film, the OCA adhesive is prepared from the following raw materials in parts by weight: 60 parts of 2-ethylhexyl acrylate, 10-20 parts of cyclohexyl acrylate, 15-25 parts of 2-hydroxyethyl acrylate, 5-10 parts of hydroxyethyl dithiodiacrylate, 0.45-1.8 parts of a photoinitiator, 0.5-2 parts of a silane coupling agent, 0.5-2 parts of 1, 2-propylene glycol, 0.5-2 parts of a curing agent, 0.5-2 parts of a curing agent, 0.5-2 parts of a curing agent and 0.5-2 parts of a curing agent. And 0.05 to 0.2 part of 1, 6-hexanediol diacrylate. In the OCA adhesive, a dynamic covalent bond repairing mechanism introduced by dithio diacrylate and a hydrogen bond mechanism of hydroxyethyl acrylate generate a synergistic effect, so that the repairing efficiency is improved in a leap-over manner; and the scratch can be efficiently repaired and the stability and definition of screen display can be maintained under the complex environments of vehicle-mounted high and low temperature, high humidity, strong ultraviolet rays and the like.

Description

High-efficiency self-healing automotive OCA adhesive, its preparation method and adhesive film Technical Field

[0001] This invention relates to the field of OCA adhesives, and particularly to a high-efficiency self-healing automotive OCA adhesive, its preparation method, and the adhesive film thereof. Background Technology

[0002] With the upgrading of automotive intelligence, in-vehicle systems have shifted from traditional mechanical dashboards to LCD dashboards, and the market's requirements for in-vehicle screen size, touch frequency, optical clarity, and damage resistance have significantly increased. However, traditional automotive OCA adhesives suffer from drawbacks such as irreversible scratches, insufficient environmental adaptability, and performance balance issues. Meanwhile, the breakthrough in polymer self-healing technology in 2000, combined with the iteration of optical adhesive technology, has provided a possibility to solve the limitations of traditional OCA. This has ultimately given rise to automotive OCA self-healing technology, which combines high light transmittance, tolerance to automotive environments, and self-scratching capabilities. This technology is suitable for special scenarios such as temperature changes of -40℃ to 85℃ and strong ultraviolet radiation in automobiles, meeting the needs for long-term clear screen display and low maintenance costs.

[0003] The main problems with existing technologies are: irreversible scratch damage, due to the rigid cross-linked network molecular structure and lack of dynamic repair sites, shallow scratches remain for a long time, resulting in a significant decline in optical performance and requiring high-cost maintenance; lack or insufficient self-healing ability, some products with a small amount of self-healing monomers have low repair efficiency and are not adapted to the extreme environment of vehicles, and the self-healing ability drops sharply after aging. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a highly efficient self-healing automotive OCA adhesive, its preparation method and adhesive film, in order to address the shortcomings of the prior art.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: In the first aspect of the present invention, a high-efficiency self-healing automotive OCA adhesive is provided, comprising the following raw materials in parts by weight: 60 parts of isooctyl acrylate, 10-20 parts of cyclohexyl acrylate, 15-25 parts of 2-hydroxyethyl acrylate, 5-10 parts of hydroxyethyl dithioacrylate, 0.45-1.8 parts of photoinitiator, 0.5-2 parts of silane coupling agent, and 0.05-0.2 parts of 1,6-hexanediol diacrylate.

[0006] Preferably, the photoinitiator is a mixture of photoinitiator 184 and photoinitiator 651.

[0007] Preferably, the photoinitiator comprises 0.15-0.6 parts of photoinitiator 184 and 0.3-1.2 parts of photoinitiator 651.

[0008] Preferably, the silane coupling agent is silane coupling agent 172.

[0009] Preferably, the high-efficiency self-healing automotive OCA adhesive comprises the following raw materials in parts by weight: 60 parts of isooctyl acrylate (2-EHA), 15 parts of cyclohexyl acrylate (CHA), 19 parts of 2-hydroxyethyl acrylate, 6 parts of hydroxyethyl dithioacrylate, 0.3 parts of photoinitiator 184, 0.6 parts of photoinitiator 651, 1 part of silane coupling agent 172, and 0.1 parts of 1,6-hexanediol diacrylate.

[0010] In a second aspect, the present invention provides a method for preparing the highly efficient self-healing automotive OCA adhesive as described above, comprising the following steps: S1, mixing isooctyl acrylate, cyclohexyl acrylate, 2-hydroxyethyl acrylate, hydroxyethyl dithioacrylate, and photoinitiator 184 in a glass reactor, and purging nitrogen gas to remove air from the glass reactor while stirring; S2, irradiating the glass reactor with a UV lamp, and indicating the start of the reaction when the temperature rises continuously, and turning off the UV lamp after the temperature reaches the target value to obtain a prepolymer; S3, adding photoinitiator 651, silane coupling agent 172, and 1,6-hexanediol diacrylate, stirring evenly, and degassing to obtain the highly efficient self-healing automotive OCA adhesive.

[0011] Preferably, the preparation method of the high-efficiency self-healing automotive OCA adhesive includes the following steps: S1, mixing isooctyl acrylate, cyclohexyl acrylate, 2-hydroxyethyl acrylate, hydroxyethyl dithioacrylate, and photoinitiator 184 in a glass reactor, and purging the reactor with nitrogen gas for 10-40 minutes at 20-30℃ and 75-300 R / min with stirring to remove air from the reactor; S2, irradiating the glass reactor with a UV lamp, controlling the irradiation energy to be 500-2000 mJ / cm². 2 When the temperature rises continuously, the reaction begins. After the temperature rises by 10-40℃, the UV lamp is turned off to obtain the prepolymer. S3, add photoinitiator 651, silane coupling agent 172, and 1,6-hexanediol diacrylate, stir evenly, and degas to obtain the high-efficiency self-healing vehicle OCA adhesive.

[0012] Preferably, in step S2, the irradiation energy is controlled to be 1000 mJ / cm². 2 Turn off the UV lamp after the temperature rises by 20°C.

[0013] Preferably, the preparation method of the high-efficiency self-healing automotive OCA adhesive includes the following steps: S1, mixing isooctyl acrylate, cyclohexyl acrylate, 2-hydroxyethyl acrylate, hydroxyethyl dithioacrylate, and photoinitiator 184 in a glass reactor, and purging the reactor with nitrogen gas for 20 minutes at 25°C and 150 R / min with stirring to remove air from the reactor; S2, irradiating the glass reactor with a UV lamp, controlling the irradiation energy to be 1000 mJ / cm². 2 When the temperature rises continuously, the reaction begins. After the temperature rises to 20°C, the UV lamp is turned off to obtain the prepolymer. S3, add photoinitiator 651, silane coupling agent 172, and 1,6-hexanediol diacrylate, stir evenly, and degas to obtain the high-efficiency self-healing vehicle OCA adhesive.

[0014] A third aspect of the present invention provides a high-efficiency self-healing automotive OCA adhesive film, which is obtained by coating and curing the high-efficiency self-healing automotive OCA adhesive as described above.

[0015] The beneficial effects of this invention are as follows: In the OCA adhesive of this invention, the dynamic covalent bond repair mechanism introduced by dithiodiacrylate and the hydrogen bonding mechanism of hydroxyethyl acrylate produce a synergistic effect, resulting in a significant improvement in repair efficiency. Specifically, the dithiodiacrylate double bond reacts rapidly under localized stress, breaking to form relatively stable sulfur free radicals. These free radicals are highly reactive and interact with other surrounding sulfur free radicals or other unsaturated bonds to form new dithio groups. This dynamic repair mechanism, working synergistically with the hydrogen bonding self-repair mechanism provided by hydroxyethyl acrylate within the system, enables the OCA adhesive in the embodiments provided by this invention to achieve a self-repair rate of 95% at room temperature for 24 hours, and even after high and low temperature cycling aging, the repair rate can still reach 85%. This fully demonstrates the key role of hydroxyethyl dithioacrylate in maintaining self-repair stability under complex conditions, ensuring efficient scratch repair and maintaining the stability and clarity of the screen display even in complex environments such as high and low temperatures, high humidity, and strong ultraviolet radiation in vehicles. Detailed Implementation

[0016] The present invention will be further described in detail below with reference to embodiments, so that those skilled in the art can implement it based on the description.

[0017] It should be understood that terms such as “having,” “comprising,” and “including” as used herein do not exclude the presence or addition of one or more other elements or combinations thereof.

[0018] Unless otherwise specified, the experimental methods used in the following examples are conventional methods. Unless otherwise specified, the materials and reagents used in the following examples are commercially available. For examples where specific conditions are not specified, conventional conditions or conditions recommended by the manufacturer are followed. For reagents or instruments whose manufacturers are not specified, they are all commercially available products.

[0019] This invention provides a highly efficient self-healing automotive OCA adhesive, comprising the following raw materials in parts by weight: 60 parts of isooctyl acrylate (2-EHA), 10-20 parts of cyclohexyl acrylate (CHA), 15-25 parts of 2-hydroxyethyl acrylate, 5-10 parts of hydroxyethyl dithioacrylate, 0.45-1.8 parts of photoinitiator, 0.5-2 parts of silane coupling agent, and 0.05-0.2 parts of 1,6-hexanediol diacrylate (HDDA).

[0020] In a preferred embodiment, the photoinitiator is a mixture of photoinitiator 184 and photoinitiator 651. More preferably, the photoinitiator comprises 0.15-0.6 parts of photoinitiator 184 and 0.3-1.2 parts of photoinitiator 651.

[0021] In a preferred embodiment, the silane coupling agent is silane coupling agent 172.

[0022] In a preferred embodiment, the high-efficiency self-healing automotive OCA adhesive comprises the following raw materials in parts by weight: 60 parts of isooctyl acrylate (2-EHA), 15 parts of cyclohexyl acrylate (CHA), 19 parts of 2-hydroxyethyl acrylate, 6 parts of hydroxyethyl dithioacrylate, 0.3 parts of photoinitiator 184, 0.6 parts of photoinitiator 651, 1 part of silane coupling agent 172, and 0.1 parts of 1,6-hexanediol diacrylate.

[0023] This invention also provides a method for preparing the above-mentioned high-efficiency self-healing automotive OCA adhesive, comprising the following steps: S1, mixing isooctyl acrylate, cyclohexyl acrylate, 2-hydroxyethyl acrylate, hydroxyethyl dithioacrylate, and photoinitiator 184 in a glass reactor, and purging nitrogen gas to remove air from the glass reactor while stirring; S2, turning on a UV lamp to irradiate the glass reactor, and indicating the start of the reaction when the temperature continuously rises, and turning off the UV lamp after the temperature reaches the target value to obtain a prepolymer; S3, adding photoinitiator 651, silane coupling agent 172, and 1,6-hexanediol diacrylate, stirring evenly, and degassing to obtain the high-efficiency self-healing automotive OCA adhesive.

[0024] In a preferred embodiment, the preparation method of the high-efficiency self-healing automotive OCA adhesive includes the following steps: S1, mixing isooctyl acrylate, cyclohexyl acrylate, 2-hydroxyethyl acrylate, hydroxyethyl dithioacrylate, and photoinitiator 184 in a glass reactor, and purging the reactor with nitrogen gas for 10-40 minutes at 20-30°C and 75-300 R / min with stirring to remove air from the reactor; S2, irradiating the glass reactor with a UV lamp, controlling the irradiation energy to be 500-2000 mJ / cm². 2 When the temperature rises continuously, the reaction begins. After the temperature rises by 10-40℃, the UV lamp is turned off to obtain the prepolymer. S3, add photoinitiator 651, silane coupling agent 172, and 1,6-hexanediol diacrylate, stir evenly, and degas to obtain a high-efficiency self-healing automotive OCA adhesive.

[0025] In a preferred embodiment, in step S2, the irradiation energy is controlled to be 1000 mJ / cm². 2 Turn off the UV lamp after the temperature rises by 20°C.

[0026] In a preferred embodiment, the preparation method of the high-efficiency self-healing automotive OCA adhesive includes the following steps: S1, mixing isooctyl acrylate, cyclohexyl acrylate, 2-hydroxyethyl acrylate, hydroxyethyl dithioacrylate, and photoinitiator 184 in a glass reactor, and purging the reactor with nitrogen gas for 20 minutes at 25°C and 150 R / min with stirring to remove air from the reactor; S2, irradiating the glass reactor with a UV lamp, controlling the irradiation energy to be 1000 mJ / cm². 2 When the temperature rises continuously, the reaction begins. After the temperature rises by 20°C, the UV lamp is turned off to obtain the prepolymer. S3, add photoinitiator 651, silane coupling agent 172, and 1,6-hexanediol diacrylate, stir evenly, and degas to obtain a high-efficiency self-healing automotive OCA adhesive.

[0027] A third aspect of the present invention provides a high-efficiency self-healing automotive OCA adhesive film, which is obtained by coating and curing the above-mentioned high-efficiency self-healing automotive OCA adhesive.

[0028] In a preferred embodiment, the thickness of the cured adhesive film is 250µm.

[0029] The above is the general concept of the present invention. Based on this, detailed embodiments and comparative examples are provided below to further illustrate the present invention.

[0030] Example 1: A high-efficiency self-healing automotive OCA adhesive, comprising the following raw materials in parts by weight: 60 parts isooctyl acrylate, 15 parts cyclohexyl acrylate, 19 parts 2-hydroxyethyl acrylate, 6 parts hydroxyethyl dithioacrylate, 0.3 parts photoinitiator 184, 0.6 parts photoinitiator 651, 1 part silane coupling agent 172, and 0.1 parts 1,6-hexanediol diacrylate.

[0031] The preparation method of this high-efficiency self-healing automotive OCA adhesive includes the following steps: S1, mixing isooctyl acrylate, cyclohexyl acrylate, 2-hydroxyethyl acrylate, hydroxyethyl dithioacrylate, and photoinitiator 184 in a glass reactor, and purging the reactor with nitrogen gas for 20 minutes at 25°C and 150 R / min under stirring to remove air from the reactor; S2, irradiating the glass reactor with a UV lamp, controlling the irradiation energy to be 1000 mJ / cm². 2 When the temperature rises continuously, the reaction begins. After the temperature rises by 20°C, the UV lamp is turned off to obtain the prepolymer. S3, add photoinitiator 651, silane coupling agent 172, and 1,6-hexanediol diacrylate, stir evenly, and degas to obtain a high-efficiency self-healing automotive OCA adhesive.

[0032] A high-efficiency self-healing automotive OCA adhesive film is prepared by coating a prepared high-efficiency self-healing automotive OCA adhesive onto a substrate and applying a 3600 mJ / cm² solution. 2 The film thickness was 250µm obtained after irradiation with a UV lamp for 3 minutes.

[0033] Comparative Example 1: A vehicle-mounted OCA adhesive, prepared by the following method: S1, by weight, 65 parts of isooctyl acrylate, 20 parts of 2-hydroxyethyl acrylate, 15 parts of isobornyl acrylate, and 0.3 parts of photoinitiator 184 are added to a glass reactor. Nitrogen gas is introduced to purge air from the reactor, maintaining the initial solution temperature at 25°C. The mixture is stirred at 150 rpm for 20 minutes. S2, UV lamp is turned on for irradiation (1000 mJ / cm²). 2 In a glass reactor, the reaction begins when the temperature rises continuously. When the temperature rises to about 20°C, the UV lamp is turned off, and a prepolymer is obtained. S3. By weight, add 0.6 parts of photoinitiator 651, 1 part of silane coupling agent 172, and 0.1 parts of 1,6-hexanediol diacrylate (HDDA) to the prepolymer, stir evenly, and degas to obtain the automotive OCA adhesive.

[0034] A type of automotive OCA adhesive film, the preparation method of which is as follows: the prepared automotive OCA adhesive is coated on a substrate and then subjected to 3600 mJ / cm 2 The film thickness was 250µm obtained after irradiation with a UV lamp for 3 minutes.

[0035] Comparative Example 2: A vehicle-mounted OCA adhesive, prepared as follows: S1, by weight, 60 parts of isooctyl acrylate, 20 parts of 2-hydroxyethyl acrylate, 15 parts of isobornyl acrylate, 5 parts of hydroxyethyl acrylate, and 0.3 parts of photoinitiator 184 are added to a glass reactor. Nitrogen gas is introduced to purge air from the reactor, maintaining the initial solution temperature at 25°C. The mixture is stirred at 150 rpm for 20 minutes. S2, UV lamp is turned on for irradiation (1000 mJ / cm²). 2 In a glass reactor, the reaction begins when the temperature rises continuously. When the temperature rises to about 20°C, the UV lamp is turned off, and a prepolymer is obtained. S3. By weight, add 0.6 parts of photoinitiator 651, 1 part of silane coupling agent 172, and 0.1 parts of 1,6-hexanediol diacrylate (HDDA) to the prepolymer, stir evenly, and degas to obtain the automotive OCA adhesive.

[0036] A type of automotive OCA adhesive film, the preparation method of which is as follows: the prepared automotive OCA adhesive is coated on a substrate and then subjected to 3600 mJ / cm 2 The film thickness was 250µm obtained after irradiation with a UV lamp for 3 minutes.

[0037] The only difference between Comparative Example 3 and Example 1 is that hydroxyethyl dithioacrylate is not added to the raw materials.

[0038] The following performance tests were performed on the automotive OCA films prepared in the examples and comparative examples: 1. The self-healing efficiency (24h) was tested using a Taber scratch tester, a diamond probe, and a laser confocal microscope. The damage depth h after scratching was measured using a laser confocal microscope. 损 After measuring the depth of damage h after repair 修 The corresponding calculation formula is: Repair efficiency = (h 损 -h 修 ) / h 损 *100%.

[0039] 2. Its optical performance was measured using a Haze-Gard Plus transmittance haze meter.

[0040] 3. After high and low temperature cycling aging, test the repair rate (50 or 100 cycles), where the cycling conditions are -40℃ to 85℃, and each temperature node is 30 minutes (30 minutes at -40℃, 30 minutes at 85℃).

[0041] 4. Peel strength test, the standard is GB / T 2792-2014.

[0042] The test results are shown in Table 1 below: Table 1 The test results above show that the traditional non-self-healing OCA adhesive prepared in Comparative Example 1 cannot repair itself once the molecular chain breaks when it encounters the same scratch. It cannot even repair itself after being left at room temperature for a week, which seriously affects the optical performance.

[0043] Comparative Example 2 is an OCA adhesive containing only simple self-healing monomers. At room temperature for 24 hours, the self-healing efficiency is only 30%, and after high and low temperature cycling aging, the self-healing efficiency is less than 15%.

[0044] Compared to Comparative Example 2, Comparative Example 3 showed a significant increase in self-healing efficiency due to the increased hydroxyl content, but it was still significantly worse than Example 1. This is because hydroxyethyl dithioacrylate was added to Example 1. The dynamic covalent bond repair mechanism introduced by the dithioacrylate and the hydrogen bond mechanism of the hydroxyethyl acrylate produced a synergistic effect, resulting in a significant improvement in repair efficiency. Disulfide double bonds react rapidly under local stress, breaking to form relatively stable sulfur free radicals. These free radicals are highly reactive and interact with other sulfur free radicals or other unsaturated bonds to form new disulfide groups. This dynamic repair mechanism, working synergistically with the hydrogen bond self-healing mechanism provided by the hydroxyethyl acrylate in the system, enabled the OCA adhesive of Example 1 to achieve a self-healing rate of 95% at room temperature for 24 hours, and even after high and low temperature cycling aging, the repair rate could still reach 85%. This fully demonstrates the key role of hydroxyethyl dithioacrylate in maintaining self-healing stability under complex conditions, ensuring efficient scratch repair and maintaining the stability and clarity of the screen display even in complex environments such as high and low temperatures, high humidity, and strong ultraviolet radiation in vehicles.

[0045] Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. For those skilled in the art, other modifications can be easily made. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details.

Claims

1. A highly efficient self-healing automotive OCA adhesive, characterized in that, The raw materials include the following parts by weight: 60 parts isooctyl acrylate, 10-20 parts cyclohexyl acrylate, 15-25 parts 2-hydroxyethyl acrylate, 5-10 parts hydroxyethyl dithioacrylate, 0.45-1.8 parts photoinitiator, 0.5-2 parts silane coupling agent, and 0.05-0.2 parts 1,6-hexanediol diacrylate.

2. The high-efficiency self-healing automotive OCA adhesive according to claim 1, characterized in that, The photoinitiator is a mixture of photoinitiator 184 and photoinitiator 651.

3. The high-efficiency self-healing automotive OCA adhesive according to claim 2, characterized in that, The photoinitiator includes 0.15-0.6 parts of photoinitiator 184 and 0.3-1.2 parts of photoinitiator 651.

4. The high-efficiency self-healing automotive OCA adhesive according to claim 1, characterized in that, The silane coupling agent is silane coupling agent 172.

5. The high-efficiency self-healing automotive OCA adhesive according to claim 1, characterized in that, The raw materials include the following parts by weight: 60 parts isooctyl acrylate, 15 parts cyclohexyl acrylate, 19 parts 2-hydroxyethyl acrylate, 6 parts hydroxyethyl dithioacrylate, 0.3 parts photoinitiator 184, 0.6 parts photoinitiator 651, 1 part silane coupling agent 172, and 0.1 parts 1,6-hexanediol diacrylate.

6. A method for preparing a high-efficiency self-healing automotive OCA adhesive as described in any one of claims 1-5, characterized in that, Includes the following steps: S1. Mix isooctyl acrylate, cyclohexyl acrylate, 2-hydroxyethyl acrylate, hydroxyethyl dithioacrylate, and photoinitiator 184 in a glass reactor. Purge the air from the glass reactor with nitrogen while stirring. S2. Turn on the UV lamp to irradiate the glass reactor. The reaction begins when the temperature rises continuously. Turn off the UV lamp after the temperature reaches the target value to obtain the prepolymer. S3. Add photoinitiator 651, silane coupling agent 172, and 1,6-hexanediol diacrylate. Stir evenly and degas to obtain the high-efficiency self-healing automotive OCA adhesive.

7. The preparation method of the high-efficiency self-healing automotive OCA adhesive according to claim 6, characterized in that, Includes the following steps: S1. Mix isooctyl acrylate, cyclohexyl acrylate, 2-hydroxyethyl acrylate, hydroxyethyl dithioacrylate, and photoinitiator 184 in a glass reactor. Purge the reactor with nitrogen gas for 10-40 minutes at 20-30℃ and 75-300 R / min while stirring to remove air from the reactor. S2. Irradiate the glass reactor with a UV lamp, controlling the irradiation energy to 500-2000 mJ / cm². 2 When the temperature rises continuously, the reaction begins. After the temperature rises by 10-40℃, the UV lamp is turned off to obtain the prepolymer. S3, add photoinitiator 651, silane coupling agent 172, and 1,6-hexanediol diacrylate, stir evenly, and degas to obtain the high-efficiency self-healing vehicle OCA adhesive.

8. The preparation method of the high-efficiency self-healing automotive OCA adhesive according to claim 7, characterized in that, In step S2, the irradiation energy is controlled to be 1000 mJ / cm². 2 Turn off the UV lamp after the temperature rises by 20°C.

9. The preparation method of the high-efficiency self-healing automotive OCA adhesive according to claim 8, characterized in that, Includes the following steps: S1. Mix isooctyl acrylate, cyclohexyl acrylate, 2-hydroxyethyl acrylate, hydroxyethyl dithioacrylate, and photoinitiator 184 in a glass reactor. Purge the reactor with nitrogen gas for 20 minutes at 25°C and 150 rpm under stirring to remove air from the reactor. S2. Irradiate the glass reactor with a UV lamp, controlling the irradiation energy to 1000 mJ / cm². 2 When the temperature rises continuously, the reaction begins. After the temperature rises to 20°C, the UV lamp is turned off to obtain the prepolymer. S3, add photoinitiator 651, silane coupling agent 172, and 1,6-hexanediol diacrylate, stir evenly, and degas to obtain the high-efficiency self-healing vehicle OCA adhesive.

10. A high-efficiency self-healing automotive OCA film, characterized in that, It is obtained by coating and curing the high-efficiency self-healing vehicle OCA adhesive as described in any one of claims 1-5.

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