Thermoplastic rubber pressure-sensitive adhesive, preparation method thereof and high-impedance support film

Abstract

The invention provides a thermoplastic rubber pressure-sensitive adhesive, a preparation method thereof and a high-impedance support film, and the thermoplastic rubber pressure-sensitive adhesive is prepared from the following raw materials in parts by weight: 100-200 parts of thermoplastic rubber elastomer, 60-100 parts of tackifying resin, 10-20 parts of oil, 1-5 parts of acrylic monomer containing three double bonds and 1-5 parts of photoinitiator, and 1-5 parts of an antioxidant. A pressure-sensitive adhesive layer prepared from the thermoplastic rubber pressure-sensitive adhesive provided by the invention simultaneously has modulus stability at high temperature, stripping force retentivity after high-temperature and high-humidity aging and high impedance characteristic.

Description

Technical Field

[0001] This invention belongs to the field of support film technology, and relates to a thermoplastic rubber pressure-sensitive adhesive, its preparation method and a high impedance support film, specifically to a high temperature and high humidity resistant thermoplastic rubber pressure-sensitive adhesive, its preparation method and a high impedance support film. Background Technology

[0002] Flexible screens, also known as flexible OLEDs, are used in the manufacture of high-end smartphones, and their application continues to expand with the development of personal smart terminals. Whether it's a foldable or candybar phone, the upper PI (polyimide) layer is very thin and flexible, leading to scratches and creases on existing flexible screens after prolonged use or folding. These scratches and creases are irreversible once formed, affecting the screen's appearance. Therefore, a support film provides the entire module with increased rigidity and protects the PI layer from scratches to address these issues.

[0003] In the field of flexible OLED display manufacturing, the support film, as a key material, must withstand high temperatures (>220°C) and maintain long-term reliability. For rubber-based materials to maintain modulus reliability at high temperatures, they need to undergo a sufficient cross-linking reaction during manufacturing. However, rubber materials that have undergone a sufficient cross-linking reaction experience a sharp decrease in peel strength after high-temperature and high-humidity aging. Currently, it is difficult to achieve a balance between high-temperature modulus reliability and controllable peel strength decline during high-temperature and high-humidity aging.

[0004] Currently, there are also support films on the market to solve the above problems. For example, CN119570408A discloses an OLED support film. This invention uses styrene-butadiene-styrene block polymer as the main material and grafts high carboxyl content acrylic copolymer to copolymerize through thermal initiation. However, in the above case, the reactivity ratio is large and the copolymerization conversion rate is low. This will result in the support film having general high temperature resistance and reduced peel strength at room temperature.

[0005] In summary, there is a need to develop a high-temperature resistant, high-temperature and high-humidity resistant, and high-resistance support film to improve the production yield of OLED modules.

[0006] It should be noted that the information disclosed in this background section is intended only to enhance the understanding of the overall background of the present invention, and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0007] To address the shortcomings of existing technologies, the present invention aims to provide a thermoplastic rubber-based pressure-sensitive adhesive, its preparation method, and a high-resistance support film. Specifically, it provides a high-temperature and high-humidity resistant thermoplastic rubber-based pressure-sensitive adhesive, its preparation method, and a high-resistance support film. The thermoplastic rubber-based pressure-sensitive adhesive provided by the present invention can effectively alleviate the problems of low high-temperature modulus and sharp drop in peel force after high-temperature and high-humidity aging of thermoplastic rubber-based pressure-sensitive adhesives. The pressure-sensitive adhesive layer made from the thermoplastic rubber-based pressure-sensitive adhesive provided by the present invention improves the high-temperature resistance, current resistance, and peel force stability of the adhesive layer during use.

[0008] To achieve this objective, the present invention adopts the following technical solution:

[0009] In a first aspect, the present invention provides a thermoplastic rubber-based pressure-sensitive adhesive, wherein the raw materials for preparing the thermoplastic rubber-based pressure-sensitive adhesive, by weight, include the following components: 100-200 parts of thermoplastic rubber elastomer, 60-100 parts of tackifying resin, 10-20 parts of oil, 1-5 parts of acrylic monomer containing 3 double bonds, 1-5 parts of photoinitiator, and 1-5 parts of antioxidant.

[0010] The thermoplastic rubber-based pressure-sensitive adhesive provided by this invention comprises a thermoplastic rubber elastomer forming a flexible skeleton through physical entanglement, a tackifying resin responsible for increasing the overall material's viscosity, and an acrylic monomer with three double bonds. The thermoplastic rubber elastomer and the acrylic monomer undergo homopolymerization. The three double bonds in the acrylic monomer possess high reactivity, providing numerous crosslinking points. Under UV irradiation, the photoinitiator decomposes to generate free radicals that polymerize with the acrylic monomer, constructing a rigid covalent crosslinked structure. The antioxidant inhibits aging and fracture by quenching free radicals, ultimately forming a physical-chemical dual-network interpenetrating structure. The pressure-sensitive adhesive layer made from the thermoplastic rubber-based pressure-sensitive adhesive provided by this invention simultaneously exhibits high-temperature modulus stability, peel strength retention after high-temperature and high-humidity aging, and high impedance characteristics.

[0011] In this invention, the amount of thermoplastic rubber elastomer used in the preparation of the thermoplastic rubber pressure-sensitive adhesive can be 100 parts, 105 parts, 110 parts, 115 parts, 120 parts, 125 parts, 130 parts, 135 parts, 140 parts, 145 parts, 150 parts, 155 parts, 160 parts, 165 parts, 170 parts, 175 parts, 180 parts, 185 parts, 190 parts, 195 parts, 200 parts, etc., based on the weight of the raw materials.

[0012] In this invention, the raw materials for preparing the thermoplastic rubber pressure-sensitive adhesive, by weight, include 60 parts, 70 parts, 80 parts, 90 parts, 100 parts, etc., of the tackifying resin.

[0013] In this invention, the amount of oil used in the preparation of the thermoplastic rubber pressure-sensitive adhesive can be 10 parts, 11 parts, 12 parts, 13 parts, 14 parts, 15 parts, 16 parts, 17 parts, 18 parts, 19 parts, 20 parts, etc., by weight.

[0014] In this invention, the amount of acrylic monomers containing three double bonds used in the preparation of the thermoplastic rubber pressure-sensitive adhesive can be 1 part, 2 parts, 3 parts, 4 parts, 5 parts, etc., by weight.

[0015] In this invention, the raw materials for preparing the thermoplastic rubber pressure-sensitive adhesive, by weight, include photoinitiator in amounts of 1 part, 2 parts, 3 parts, 4 parts, 5 parts, etc.

[0016] In this invention, the amount of antioxidant used in the preparation of the thermoplastic rubber pressure-sensitive adhesive can be 1 part, 2 parts, 3 parts, 4 parts, 5 parts, etc., by weight.

[0017] Preferably, the thermoplastic rubber elastomer comprises a styrene-butadiene-styrene block polymer elastomer.

[0018] Preferably, the tackifying resin includes any one or a combination of at least two of terpene phenol resins and rosin resins.

[0019] Preferably, the oil comprises mineral oil and / or lubricating oil.

[0020] Preferably, the acrylic monomer containing three double bonds includes trimethylolpropane triacrylate.

[0021] Preferably, the photoinitiator comprises hydroxycyclohexylphenyl ketone and / or trimethylbenzoyl-diphenylphosphine oxide.

[0022] Preferably, the antioxidant comprises pentaerythritol pentahydroxystearate and / or triethylene glycol dipropionate.

[0023] Preferably, the raw materials for preparing the thermoplastic rubber pressure-sensitive adhesive also include other acrylic monomers.

[0024] Preferably, the other acrylic monomers include methyl methacrylate.

[0025] Preferably, the raw materials for preparing the thermoplastic rubber pressure-sensitive adhesive also include a solvent.

[0026] Preferably, the solvent includes ethyl acetate and / or toluene.

[0027] Preferably, the solid content of the thermoplastic rubber pressure-sensitive adhesive is 45%-55%, such as 45%, 46%, 47%, 48%, 49%, 50%, 51%, 52%, 53%, 54%, 55%, etc.

[0028] Preferably, the viscosity of the thermoplastic rubber pressure-sensitive adhesive is 1000-3000 cps, such as 1000 cps, 1200 cps, 1400 cps, 1500 cps, 1600 cps, 1800 cps, 2000 cps, 2200 cps, 2400 cps, 2500 cps, 2600 cps, 2800 cps, 3000 cps, etc.

[0029] In a second aspect, the present invention provides a method for preparing a thermoplastic rubber-based pressure-sensitive adhesive as described in the first aspect, the method comprising the following steps:

[0030] (1) Mix the thermoplastic rubber elastomer and solvent, then add the tackifying resin and oil, and mix again;

[0031] (2) Add acrylic monomers containing three double bonds, photoinitiator and antioxidant to the system of step (1) and mix to obtain the thermoplastic rubber pressure-sensitive adhesive.

[0032] Preferably, the mixing method in step (1) includes stirring.

[0033] Preferably, the mixing time in step (1) is 1-2 hours, such as 1 hour, 1.5 hours, 2 hours, etc.

[0034] Preferably, the remixing method in step (1) includes stirring.

[0035] Preferably, the remixing time in step (1) is 20-30 minutes, such as 20 minutes, 25 minutes, 30 minutes, etc.

[0036] Preferably, step (2) of adding an acrylic monomer containing three double bonds, a photoinitiator, and an antioxidant to the system of step (1) specifically includes:

[0037] The acrylic monomer containing three double bonds, the photoinitiator, and the antioxidant are mixed with the solvent to obtain the corresponding diluent, and then added to the system in step (1).

[0038] Preferably, the mixing method in step (2) includes stirring.

[0039] Preferably, the mixing time in step (2) is 10-20 min, such as 10 min, 15 min, 20 min, etc.

[0040] Preferably, after mixing in step (2), a vacuuming process is further included, the purpose of which is to remove air bubbles from the adhesive.

[0041] Thirdly, the present invention provides a high-impedance support film, the high-impedance support film comprising a protective film, a substrate layer, a pressure-sensitive adhesive layer and a release film layer stacked sequentially, wherein the raw materials for preparing the pressure-sensitive adhesive layer include the thermoplastic rubber-based pressure-sensitive adhesive as described in the first aspect.

[0042] Preferably, the protective film is an acrylic protective film.

[0043] Preferably, the substrate layer is made of polyethylene terephthalate (PET).

[0044] Preferably, the thickness of the substrate layer is 50-100μm, such as 50μm, 55μm, 60μm, 65μm, 70μm, 75μm, 80μm, 85μm, 90μm, 95μm, 100μm, etc.

[0045] Preferably, the thickness of the pressure-sensitive adhesive layer is 5-20 μm, such as 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, 11 μm, 12 μm, 13 μm, 14 μm, 15 μm, 16 μm, 17 μm, 18 μm, 19 μm, 20 μm, etc.

[0046] Preferably, the release film layer is a double-sided antistatic release film.

[0047] Preferably, the thickness of the release film layer is 25-80 μm, such as 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, 50 μm, 55 μm, 60 μm, 65 μm, 70 μm, 75 μm, 80 μm, etc.

[0048] Preferably, the impedance value of the high-impedance support film is 14-16 Ω·cm, such as 14 Ω·cm, 14.5 Ω·cm, 15 Ω·cm, 15.5 Ω·cm, 16 Ω·cm, etc.

[0049] The present invention does not specifically limit the preparation method of the high-resistivity support film. Exemplarily, it is prepared by the following method:

[0050] Thermoplastic rubber pressure-sensitive adhesive is applied to the corona-exposed surface of the substrate using a slit or scraper coating method. After drying in an oven, the release film substrate is laminated to the side of the substrate coated with thermoplastic rubber pressure-sensitive adhesive, and then subjected to appropriate UV light irradiation. Finally, the protective film is laminated to the non-adhesive surface of the substrate and flattened to obtain the high-resistance support film.

[0051] Compared with the prior art, the present invention has the following beneficial effects:

[0052] The thermoplastic rubber-based pressure-sensitive adhesive provided by this invention comprises a thermoplastic rubber elastomer forming a flexible skeleton through physical entanglement, a tackifying resin responsible for increasing the overall material's viscosity, and an acrylic monomer with three double bonds. The thermoplastic rubber elastomer and the acrylic monomer undergo homopolymerization. The three double bonds in the acrylic monomer possess high reactivity, providing numerous crosslinking points. Under UV irradiation, the photoinitiator decomposes to generate free radicals that polymerize with the acrylic monomer, constructing a rigid covalent crosslinked structure. The antioxidant inhibits aging and fracture by quenching free radicals, ultimately forming a physical-chemical dual-network interpenetrating structure. The pressure-sensitive adhesive layer made from the thermoplastic rubber-based pressure-sensitive adhesive provided by this invention simultaneously exhibits high-temperature modulus stability, peel strength retention after high-temperature and high-humidity aging, and high impedance characteristics. Detailed Implementation

[0053] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.

[0054] Unless otherwise expressly stated, throughout the specification and claims, the term "comprising" or its variations such as "including" or "comprises" shall be understood to include the stated elements or components without excluding other elements or other components.

[0055] Example 1

[0056] This embodiment provides a thermoplastic rubber pressure-sensitive adhesive. The raw materials for preparing the thermoplastic rubber pressure-sensitive adhesive include the following components: 100g thermoplastic rubber elastomer, 100g tackifying resin, 10g oil, 5g acrylic monomer containing 3 double bonds, 2.5g photoinitiator, 4.4g antioxidant, and 210g ethyl acetate.

[0057] Among them, the thermoplastic rubber elastomer is DX022, the tackifying resin is TP96, the oil is liquid paraffin oil, the acrylic monomer containing three double bonds is trimethylolpropane triacrylate, the photoinitiator is photoinitiator 184, and the antioxidant is antioxidant 1010.

[0058] The preparation method of the thermoplastic rubber pressure-sensitive adhesive includes the following steps:

[0059] Add 100g of thermoplastic elastomer and 150g of ethyl acetate to a mixing tank, stir thoroughly until dissolved, then add 100g of tackifying resin and 10g of oil to the mixing tank.

[0060] Add 5g of acrylic monomer containing three double bonds to a measuring cup, and dilute and disperse it evenly with 20g of ethyl acetate. Add 2.5g of photoinitiator to another measuring cup, and dilute and disperse it evenly with 20g of ethyl acetate. Add 4.4g of antioxidant to another measuring cup, and dilute and disperse it evenly with 20g of ethyl acetate. Add the diluted solutions from the three measuring cups to a mixing tank and continue stirring for 20 minutes to obtain the thermoplastic rubber-like pressure-sensitive adhesive.

[0061] Vacuum treatment is performed on plastic rubber pressure-sensitive adhesives to remove the gas inside the adhesive.

[0062] Example 2

[0063] This embodiment provides a thermoplastic rubber pressure-sensitive adhesive. The raw materials for preparing the thermoplastic rubber pressure-sensitive adhesive include the following components: 100g thermoplastic rubber elastomer, 100g tackifying resin, 10g oil, 2.5g acrylic monomer containing 3 double bonds, 2.5g photoinitiator, 2g antioxidant, and 210g ethyl acetate.

[0064] Among them, the thermoplastic rubber elastomer is DX022, the tackifying resin is TP96, the oil is liquid paraffin oil, the acrylic monomer containing three double bonds is trimethylolpropane triacrylate, the photoinitiator is photoinitiator 184, and the antioxidant is antioxidant 1010.

[0065] The preparation method of the thermoplastic rubber pressure-sensitive adhesive includes the following steps:

[0066] Add 100g of thermoplastic elastomer and 150g of ethyl acetate to a mixing tank, stir thoroughly until dissolved, then add 100g of tackifying resin and 10g of oil to the mixing tank.

[0067] Add 2.5g of acrylic monomer containing three double bonds to a measuring cup, and dilute and disperse it evenly with 20g of ethyl acetate. Add 2.5g of photoinitiator to another measuring cup, and dilute and disperse it evenly with 20g of ethyl acetate. Add 2g of antioxidant to another measuring cup, and dilute and disperse it evenly with 20g of ethyl acetate. Add the diluted solutions from the three measuring cups to a mixing tank and continue stirring for 20 minutes to obtain a thermoplastic rubber-based pressure-sensitive adhesive.

[0068] Vacuum treatment is performed on thermoplastic rubber pressure-sensitive adhesives to remove the gas inside the adhesive.

[0069] Example 3

[0070] This embodiment provides a thermoplastic rubber pressure-sensitive adhesive. The raw materials for preparing the thermoplastic rubber pressure-sensitive adhesive include the following components: 100g thermoplastic rubber elastomer, 100g tackifying resin, 10g oil, 5g acrylic monomer containing 3 double bonds, 1g photoinitiator, 4.4g antioxidant, and 210g ethyl acetate.

[0071] Among them, the thermoplastic rubber elastomer is DX022, the tackifying resin is TP96, the oil is liquid paraffin oil, the acrylic monomer containing three double bonds is trimethylolpropane triacrylate, the photoinitiator is photoinitiator 184, and the antioxidant is antioxidant 1010.

[0072] The preparation method of the thermoplastic rubber pressure-sensitive adhesive includes the following steps:

[0073] Add 100g of thermoplastic elastomer and 150g of ethyl acetate to a mixing tank, stir thoroughly until dissolved, then add 100g of tackifying resin and 10g of oil to the mixing tank.

[0074] Add 5g of acrylic monomer containing three double bonds to one measuring cup, and dilute and disperse it evenly with 20g of ethyl acetate. Add 1g of photoinitiator to another measuring cup, and dilute and disperse it evenly with 20g of ethyl acetate. Add 4.4g of antioxidant to another measuring cup, and dilute and disperse it evenly with 20g of ethyl acetate. Add the diluted solutions from the three measuring cups to a mixing tank and continue stirring for 20 minutes to obtain a thermoplastic rubber-based pressure-sensitive adhesive.

[0075] Vacuum treatment is performed on thermoplastic rubber pressure-sensitive adhesives to remove the gas inside the adhesive.

[0076] Example 4

[0077] This embodiment provides a thermoplastic rubber pressure-sensitive adhesive. The raw materials for preparing the thermoplastic rubber pressure-sensitive adhesive include the following components: 100g thermoplastic rubber elastomer, 60g tackifying resin, 10g oil, 5g acrylic monomer containing 3 double bonds, 2.5g photoinitiator, 4.4g antioxidant, and 210g ethyl acetate.

[0078] Among them, the thermoplastic rubber elastomer is DX022, the tackifying resin is TP96, the oil is liquid paraffin oil, the acrylic monomer containing three double bonds is trimethylolpropane triacrylate, the photoinitiator is photoinitiator 184, and the antioxidant is antioxidant 1010.

[0079] The preparation method of the thermoplastic rubber pressure-sensitive adhesive includes the following steps:

[0080] Add 100g of thermoplastic elastomer and 150g of ethyl acetate to a mixing tank, stir thoroughly until dissolved, then add 60g of tackifying resin and 10g of oil to the mixing tank.

[0081] Add 5g of acrylic monomer containing three double bonds to a measuring cup and dilute with 20g of ethyl acetate until evenly dispersed. Add 2.5g of photoinitiator to another measuring cup and dilute with 20g of ethyl acetate until evenly dispersed. Add 4.4g of antioxidant to yet another measuring cup and dilute with 20g of ethyl acetate until evenly dispersed. Add the diluted solutions from the three measuring cups to a mixing tank and continue stirring for 20 minutes to obtain a thermoplastic rubber-based pressure-sensitive adhesive.

[0082] Vacuum treatment is performed on thermoplastic rubber pressure-sensitive adhesives to remove the gas inside the adhesive.

[0083] Example 5

[0084] This embodiment provides a thermoplastic rubber pressure-sensitive adhesive. The raw materials for preparing the thermoplastic rubber pressure-sensitive adhesive include the following components: 100g thermoplastic rubber elastomer, 100g tackifying resin, 10g oil, 5g acrylic monomer containing 3 double bonds, 2.5g photoinitiator, 4.4g antioxidant, and 210g ethyl acetate.

[0085] The thermoplastic elastomer is D1119, the tackifying resin is TP7042, the oil is liquid paraffin oil, the acrylic monomer containing three double bonds is trimethylolpropane triacrylate, the photoinitiator is photoinitiator 184, and the antioxidant is antioxidant 1010.

[0086] The preparation method of the thermoplastic rubber pressure-sensitive adhesive includes the following steps:

[0087] Add 100g of thermoplastic elastomer and 150g of ethyl acetate to a mixing tank, stir thoroughly until dissolved, then add 100g of tackifying resin and 10g of oil to the mixing tank.

[0088] Add 5g of acrylic monomer containing three double bonds to a measuring cup and dilute with 20g of ethyl acetate until evenly dispersed. Add 2.5g of photoinitiator to another measuring cup and dilute with 20g of ethyl acetate until evenly dispersed. Add 4.4g of antioxidant to yet another measuring cup and dilute with 20g of ethyl acetate until evenly dispersed. Add the diluted solutions from the three measuring cups to a mixing tank and continue stirring for 20 minutes to obtain a thermoplastic rubber-based pressure-sensitive adhesive.

[0089] Vacuum treatment is performed on thermoplastic rubber pressure-sensitive adhesives to remove the gas inside the adhesive.

[0090] Comparative Example 1

[0091] The only difference between this comparative example and Example 1 is that the acrylic monomer (trimethylolpropane triacrylate) containing three double bonds is replaced with an equal weight of methyl methacrylate.

[0092] Comparative Example 2

[0093] The only difference between this comparative example and Example 1 is that the amount of acrylic monomer (trimethylolpropane triacrylate) containing three double bonds is 10g.

[0094] Comparative Example 3

[0095] The only difference between this comparative example and Example 1 is that the amount of acrylic monomer (trimethylolpropane triacrylate) containing three double bonds is 1g.

[0096] Application Example 1

[0097] In this application example, a high-resistance support film is provided, which includes a protective film, a PET substrate layer, a pressure-sensitive adhesive layer and a release film layer stacked sequentially.

[0098] The preparation method includes the following steps:

[0099] On a 75μm thick PET film, the thermoplastic rubber-based pressure-sensitive adhesive provided in Example 1 was applied to the corona-exposed surface of the PET film using a slot coating method. After drying in an oven, a pressure-sensitive adhesive layer was obtained. A release film was then laminated to the adhesive surface (i.e., the pressure-sensitive adhesive layer), and UV light was applied (total light energy of 2000mJ). An acrylic protective film was then laminated to the non-adhesive surface of the PET film and flattened to obtain a high-resistance support film. The dry adhesive thickness of the pressure-sensitive adhesive layer was 13μm. Note: This thickness refers to the average thickness.

[0100] Application Example 2-5, Comparison with Application Example 1-3

[0101] The only difference from Application Example 1 is that the thermoplastic rubber pressure-sensitive adhesive provided in Example 1 is replaced with the thermoplastic rubber pressure-sensitive adhesive provided in Examples 2-5 and Comparative Examples 1-3.

[0102] The performance of the thermoplastic rubber pressure-sensitive adhesive, application examples, and comparative application examples provided in the embodiments and comparative examples of the present invention was tested using the following methods:

[0103] (1) Peeling force at room temperature: Remove the release film, stick it on the glass interface, and roll it back and forth twice with a 2KG roller at 300mm / min. Then, let it stand at room temperature for 20 minutes before testing the peeling force. The test temperature is 25±5℃ and 50±5%RH.

[0104] (2) Peel strength after 10 days at high temperature and high humidity 85℃ and 85% RH: Remove the release film, stick it on the glass interface, and roll it back and forth twice with a 2KG roller at 300mm / min. Then, let it stand at room temperature for 20 minutes and place it in a high temperature and high humidity 85℃ and 85% RH aging test chamber for 10 days. After taking it out, let it stand at room temperature for 2 hours and then perform a peel strength test. The test temperature is 25±5℃ and 50±5%RH.

[0105] (3) High-temperature modulus: Thermoplastic rubber pressure-sensitive adhesive was coated on the release film, dried in an oven, and then the release film was laminated with the adhesive surface and subjected to UV irradiation (total irradiation energy of 2000mJ). The thermoplastic rubber pressure-sensitive adhesive was stacked to a thickness of 1000μm, and the storage modulus at 25℃ and 220℃ was tested at a frequency of 1Hz under tensile mode by heating from -20℃ to 220℃ at a rate of 3℃ / min.

[0106] (4) Impedance value: Tear off the release film and use an impedance meter to measure the surface resistivity at a DC voltage of 500V.

[0107] The performance test results are shown in Table 1.

[0108] Table 1

[0109]

[0110] As can be seen from Table 1, the support film made of the thermoplastic rubber pressure-sensitive adhesive provided by the present invention can simultaneously meet the requirements of stable high temperature modulus, excellent peel strength at room temperature, high peel strength retention rate under high temperature and high humidity aging, and high impedance value.

[0111] Compared with Example 1, the thermoplastic rubber pressure-sensitive adhesive provided in Comparative Example 1 has a lower high-temperature modulus. The support film made from the thermoplastic rubber pressure-sensitive adhesive provided in Comparative Example 2 has lower peel strength at room temperature and lower peel strength after 10 days of high temperature and high humidity. The thermoplastic rubber pressure-sensitive adhesive provided in Comparative Example 3 has a lower high-temperature modulus at 220°C. The support film made from the thermoplastic rubber pressure-sensitive adhesive provided in Comparative Example 3 has lower peel strength after 10 days of high temperature and high humidity.

[0112] The applicant declares that this invention illustrates the thermoplastic rubber-based pressure-sensitive adhesive, its preparation method, and the high-resistance support film through the above embodiments. However, this invention is not limited to the above embodiments, meaning that this invention does not necessarily rely on the above embodiments for implementation. Those skilled in the art should understand that any improvements to this invention, equivalent substitutions of the raw materials used, additions of auxiliary components, and selection of specific methods all fall within the protection and disclosure scope of this invention.

Claims

1. A thermoplastic rubber-based pressure-sensitive adhesive, characterized in that, The raw materials for preparing the thermoplastic rubber pressure-sensitive adhesive include the following components by weight: 100-200 parts of thermoplastic rubber elastomer, 60-100 parts of tackifying resin, 10-20 parts of oil, 1-5 parts of acrylic monomer containing 3 double bonds, 1-5 parts of photoinitiator, and 1-5 parts of antioxidant.

2. The thermoplastic rubber pressure-sensitive adhesive according to claim 1, characterized in that, The thermoplastic rubber elastomer includes a styrene-butadiene-styrene block polymer elastomer; Preferably, the tackifying resin includes any one or a combination of at least two of terpene phenol resins and rosin resins.

3. The thermoplastic rubber pressure-sensitive adhesive according to claim 1 or 2, characterized in that, The oil includes mineral oil and / or lubricating oil; Preferably, the acrylic monomer containing three double bonds includes trimethylolpropane triacrylate.

4. The thermoplastic rubber pressure-sensitive adhesive according to any one of claims 1-3, characterized in that, The photoinitiator includes hydroxycyclohexylphenyl ketone and / or trimethylbenzoyl-diphenylphosphine oxide; Preferably, the antioxidant comprises pentaerythritol pentahydroxystearate and / or triethylene glycol dipropionate.

5. The thermoplastic rubber pressure-sensitive adhesive according to any one of claims 1-4, characterized in that, The raw materials for preparing the thermoplastic rubber pressure-sensitive adhesive also include other acrylic monomers; Preferably, the other acrylic monomers include methyl methacrylate; Preferably, the raw materials for preparing the thermoplastic rubber pressure-sensitive adhesive also include a solvent; Preferably, the solvent includes ethyl acetate and / or toluene.

6. The thermoplastic rubber pressure-sensitive adhesive according to any one of claims 1-5, characterized in that, The solid content of the thermoplastic rubber pressure-sensitive adhesive is 45%-55%; Preferably, the viscosity of the thermoplastic rubber pressure-sensitive adhesive is 1000-3000 cps.

7. A method for preparing a thermoplastic rubber-based pressure-sensitive adhesive as described in any one of claims 1-6, characterized in that, The preparation method includes the following steps: (1) Mix the thermoplastic rubber elastomer and solvent, then add the tackifying resin and oil, and mix again; (2) Add acrylic monomers containing three double bonds, photoinitiator and antioxidant to the system of step (1) and mix to obtain the thermoplastic rubber pressure-sensitive adhesive.

8. The preparation method according to claim 7, characterized in that, The mixing method described in step (1) includes stirring; Preferably, the mixing time in step (1) is 1-2 hours; Preferably, the remixing method in step (1) includes stirring; Preferably, the remixing time in step (1) is 20-30 minutes; Preferably, step (2) of adding an acrylic monomer containing three double bonds, a photoinitiator, and an antioxidant to the system of step (1) specifically includes: The acrylic monomer containing three double bonds, the photoinitiator, and the antioxidant are mixed with the solvent to obtain the corresponding diluent, and then added to the system in step (1); Preferably, the mixing method in step (2) includes stirring; Preferably, the mixing time in step (2) is 10-20 min; Preferably, step (2) further includes a vacuuming process after mixing.

9. A high-resistivity support film, characterized in that, The high-resistance support film comprises a protective film, a substrate layer, a pressure-sensitive adhesive layer, and a release film layer stacked sequentially, wherein the raw material for preparing the pressure-sensitive adhesive layer comprises a thermoplastic rubber-based pressure-sensitive adhesive as described in any one of claims 1-6.

10. The high-resistivity support film according to claim 9, characterized in that, The protective film is an acrylic protective film; Preferably, the substrate layer is made of polyethylene terephthalate; Preferably, the thickness of the substrate layer is 50-100 μm; Preferably, the thickness of the pressure-sensitive adhesive layer is 5-20 μm; Preferably, the release film layer is a double-sided antistatic release film; Preferably, the thickness of the release film layer is 25-80 μm.

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