Solvent type high-temperature-resistant acrylic pressure-sensitive adhesive protective film and preparation method thereof
The solvent-based high-temperature resistant acrylic pressure-sensitive adhesive prepared by solution polymerization utilizes heat-resistant monomers and crosslinking agents to form a stable crosslinked structure, solving the problem of decreased adhesion of pressure-sensitive adhesives at high temperatures and achieving stable bonding performance in high-temperature environments.
Patent Information
- Application Number
- CN202511643904.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-11
- Publication Date
- 2026-02-10
AI Technical Summary
Existing solvent-based pressure-sensitive adhesives exhibit reduced adhesion at high temperatures, leading to issues such as dripping, residue, bubbling, and detachment, thus failing to meet the bonding and fixing requirements under high-temperature conditions.
A solvent-based high-temperature resistant acrylic pressure-sensitive adhesive was prepared by solution polymerization. By introducing specific heat-resistant monomers and crosslinking agents, a stable crosslinked structure was formed, thereby improving the high-temperature resistance of the pressure-sensitive adhesive.
It maintains stable bonding performance in high-temperature environments, with no glue overflow, bubbling, or residue after 180℃*4h, which is significantly better than traditional acrylic pressure-sensitive adhesives.
Smart Images
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Abstract
Description
Technical Field
[0001] This application relates to the field of high-temperature resistant protective film preparation, and in particular to a solvent-based high-temperature resistant acrylic pressure-sensitive adhesive protective film and its preparation method. Background Technology
[0002] Pressure-sensitive adhesives (PSA) are adhesives that bond materials together under slight pressure. Due to their advantages such as rapid bonding and ease of use, they are widely used in electronics, automotive, medical, and packaging industries. While commonly used solvent-based PSA tapes possess good adhesion and processing properties, their tackiness decreases rapidly at high temperatures, potentially leading to dripping, residue buildup, bubbling, and detachment, making them unsuitable for bonding and fixing applications in high-temperature environments. Currently, most high-temperature resistant PSA tapes on the market are silicone-based, epoxy-based, or acrylic-based.
[0003] Silicone-based pressure-sensitive adhesives offer good high-temperature resistance but are expensive, have relatively low tack, are prone to silicon transfer, require high curing temperatures, and some require metal catalysts, thus limiting their applications. Epoxy-based pressure-sensitive adhesives are resistant to high temperatures and chemical corrosion, and are easy to modify, but are expensive, brittle after curing, have high requirements for substrate surface quality, and are prone to leaving residues and visual traces when the molecular weight is low. Acrylic adhesives are low-cost, easy to apply, do not undergo phase separation, and have a wide range of applications, but their temperature resistance is relatively poor. During high-temperature peeling, the adhesive layer undergoes cohesive failure instead of adhesive adhesion, leaving residues on the surface of the adhered object. Summary of the Invention
[0004] To improve the high-temperature resistance of pressure-sensitive adhesives, this application provides a solvent-based high-temperature resistant acrylic pressure-sensitive adhesive protective film and its preparation method.
[0005] Firstly, this application provides a solvent-based high-temperature resistant acrylic pressure-sensitive adhesive protective film, which adopts the following technical solution: A solvent-based high-temperature resistant acrylic pressure-sensitive adhesive protective film includes a pressure-sensitive adhesive layer and a substrate layer. By weight, the pressure-sensitive adhesive layer comprises the following components: 1-5 parts acrylic acid, 10-30 parts butyl acrylate, 50-80 parts isooctyl acrylate, 1-5 parts hydroxyethyl acrylate, 1-10 parts vinyl acetate, 0.5-2 parts initiator, 1-10 parts heat-resistant monomer, 0.5-2 parts curing agent, 90-130 parts ethyl acetate, and 60-90 parts toluene.
[0006] Preferably, the pressure-sensitive adhesive layer comprises the following components: 2 parts acrylic acid, 20 parts butyl acrylate, 65 parts isooctyl acrylate, 2 parts hydroxyethyl acrylate, 5 parts vinyl acetate, 0.8 parts initiator, 6 parts heat-resistant monomer, 0.5-1.7 parts curing agent, 120 parts ethyl acetate, and 80 parts toluene.
[0007] Preferably, the substrate layer is 25PI and the pressure-sensitive layer has a thickness of 20μm.
[0008] Preferably, the heat-resistant monomer is any one of N-vinylcarbazole, maleimide, and N-vinylpyrrolidone.
[0009] Preferably, the initiator is either benzoyl peroxide or azobisisobutyronitrile.
[0010] Preferably, the curing agent is any one of hexamethylene diisocyanate, aluminum acetylacetonate, and m-phenylenediamine epoxide.
[0011] Secondly, this application provides a method for preparing a solvent-based high-temperature resistant acrylic pressure-sensitive adhesive protective film, using the following technical solution: A method for preparing a solvent-based high-temperature resistant acrylic pressure-sensitive adhesive protective film includes the following steps: S1. Preparation of high-temperature resistant acrylic prepolymer: The monomers isooctyl acrylate, butyl acrylate, hydroxyethyl acrylate, vinyl acetate, acrylic acid, and heat-resistant monomers are weighed and uniformly mixed to obtain a mixed monomer. The solution polymerization method is adopted. In the reaction vessel equipped with nitrogen gas, thermometer and reflux device, initiator, ethyl acetate, toluene and two-thirds of the mixed monomer are added. After heating, the reaction is maintained at the temperature. The remaining mixed monomer, initiator, ethyl acetate and toluene are added to the system through constant pressure dropping funnel. The temperature is continued to rise and the reaction is maintained at the temperature. After cooling, the material is discharged to obtain high temperature resistant acrylic prepolymer. S2. Preparation of solvent-based high-temperature resistant acrylic pressure-sensitive adhesive: High-temperature resistant acrylic prepolymer and curing agent are added to a mixing tank, stirred, and then the mixture is sealed and stored. S3. Preparation of solvent-based high-temperature resistant acrylic pressure-sensitive adhesive protective film: Using a coater, the mixture obtained in step S2 is uniformly coated onto PI, cured, aged, and stored to obtain a solvent-based high-temperature resistant acrylic pressure-sensitive adhesive protective film.
[0012] In summary, this application includes at least one of the following beneficial technical effects: 1. The high-temperature resistant acrylic pressure-sensitive adhesive of this application can maintain stable bonding performance in high-temperature environments. The pressure-sensitive adhesive can withstand 180℃*4h, and there is no overflow, bubbling or residue within 20 minutes at 260℃, which is significantly better than traditional acrylic pressure-sensitive adhesives.
[0013] 2. By introducing specific heat-resistant monomers and crosslinking agents, which work synergistically with acrylate monomers, a more stable structure with higher heat resistance is formed, making the pressure-sensitive adhesive less prone to decomposition or loss of tack at high temperatures. Attached Figure Description
[0014] Figure 1 The polymerization reaction formula for the high-temperature resistant acrylic prepolymer HTRAP in Example 1; Figure 2 The infrared spectrum of the high-temperature resistant acrylic prepolymer HTRAP in Example 1; Figure 3 The effect of hexamethylene diisocyanate dosage on the 180° peel strength of PSA in Example 1; Figure 4 The effect of aluminum acetylacetone dosage on the 180° peel strength of PSA in Example 2; Figure 5 The effect of the amount of epoxidized m-phenylenediamine on the 180° peel strength of PSA in Example 3; Figure 6 The effect of the amount of latent curing agent 3175 on the 180° peel strength of PSA-coated steel sheets in Example 4; Figure 7 The effect of the amount of latent curing agent 3175 on the 180° peel strength of PSA-laminated LCP plates in Example 4; Figure 8 The effect of the amount of latent curing agent 3575 on the 180° peel strength of PSA-coated steel sheets in Example 5; Figure 9 The effect of the amount of latent curing agent 3575 in Example 5 on the 180° peel strength of PSA-laminated LCP plates. Detailed Implementation
[0015] The present application will be further described in detail below with reference to the embodiments: Raw material description: All raw materials used in the examples are commercially available; Example 1 The heat-resistant monomer is maleimide, the initiator is benzoyl peroxide, and the curing agent is hexamethylene diisocyanate.
[0016] The composition of the high-temperature resistant acrylic prepolymer includes: 2 parts acrylic acid, 20 parts butyl acrylate, 65 parts isooctyl acrylate, 2 parts hydroxyethyl acrylate, 5 parts vinyl acetate, 0.8 parts benzoyl peroxide, 6 parts maleimide, 120 parts ethyl acetate, and 80 parts toluene.
[0017] The formulation of a solvent-based high-temperature resistant acrylic pressure-sensitive adhesive protective film includes 100 parts of high-temperature resistant acrylic prepolymer and 0.5 parts of hexamethylene diisocyanate.
[0018] Preparation of solvent-based high-temperature resistant acrylic pressure-sensitive adhesive protective film: S1. Preparation of high-temperature resistant acrylic prepolymer: After weighing and uniformly mixing monomers isooctyl acrylate, butyl acrylate, hydroxyethyl acrylate, vinyl acetate, acrylic acid, and maleimide, solution polymerization was carried out in a reactor equipped with nitrogen gas, a thermometer, and a reflux device. 0.4 parts of initiator, 80 parts of ethyl acetate, 50 parts of toluene, and two-thirds of the mixed monomers were added. The temperature was raised to 80°C and the reaction was maintained for 1 hour. The remaining mixed monomers, initiator, ethyl acetate, and toluene were added to the system through a constant pressure dropping funnel. The temperature was raised to 85°C and the reaction was maintained for 4 hours. After cooling, the material was discharged to obtain a pale yellow, transparent, high-temperature resistant acrylic prepolymer. S2. Preparation of solvent-based high-temperature resistant acrylic pressure-sensitive adhesive: High-temperature resistant acrylic prepolymer and hexamethylene diisocyanate were added to a mixing tank and stirred at 500 rpm for 30 minutes to obtain a mixture, which was then sealed and stored. S3. Preparation of solvent-based high-temperature resistant acrylic pressure-sensitive adhesive protective film: The mixture was evenly coated onto PI using a coater, cured at 85℃ for 3 minutes, aged at 60℃ for 24 hours, and then stored at 23℃ / 50%RH to obtain a solvent-based high-temperature resistant acrylic pressure-sensitive adhesive protective film.
[0019] Example 2 Example 2 is based on Example 1, and the amount of hexamethylene diisocyanate used in Example 2 is 0.8 parts.
[0020] Example 3 Example 3 is based on Example 1, and the amount of hexamethylene diisocyanate used in Example 3 is 1.1 parts.
[0021] Example 4 Example 4 is based on Example 1, and the amount of hexamethylene diisocyanate used in Example 4 is 1.4 parts.
[0022] Example 5 Example 5 is based on Example 1, and the amount of hexamethylene diisocyanate used in Example 5 is 1.7 parts.
[0023] Example 6 The heat-resistant monomer is maleimide, the initiator is benzoyl peroxide, and the curing agent is aluminum acetylacetonate.
[0024] The composition of the high-temperature resistant acrylic prepolymer includes: 2 parts acrylic acid, 20 parts butyl acrylate, 65 parts isooctyl acrylate, 2 parts hydroxyethyl acrylate, 5 parts vinyl acetate, 0.8 parts benzoyl peroxide, 6 parts maleimide, 120 parts ethyl acetate, and 80 parts toluene.
[0025] The formulation of the solvent-based high-temperature resistant acrylic pressure-sensitive adhesive protective film includes 100 parts of high-temperature resistant acrylic prepolymer and 0.5 parts of aluminum acetylacetonate.
[0026] S1. Preparation of high-temperature resistant acrylic prepolymer: After weighing and uniformly mixing monomers isooctyl acrylate, butyl acrylate, hydroxyethyl acrylate, vinyl acetate, acrylic acid, and maleimide, solution polymerization was carried out in a reactor equipped with nitrogen gas, a thermometer, and a reflux device. 0.4 parts of initiator, 80 parts of ethyl acetate, 50 parts of toluene, and two-thirds of the mixed monomers were added. The temperature was raised to 80°C and the reaction was maintained for 1 hour. The remaining mixed monomers, initiator, ethyl acetate, and toluene were added to the system through a constant pressure dropping funnel. The temperature was raised to 85°C and the reaction was maintained for 4 hours. After cooling, the material was discharged to obtain a pale yellow, transparent, high-temperature resistant acrylic prepolymer. S2. Preparation of solvent-based high-temperature resistant acrylic pressure-sensitive adhesive: High-temperature resistant acrylic prepolymer and aluminum acetylacetonate were added to a mixing tank and stirred at 500 r / min for 30 min to obtain a mixture, which was then sealed and stored. S3. Preparation of solvent-based high-temperature resistant acrylic pressure-sensitive adhesive protective film: The mixture was evenly coated onto PI using a coater, cured at 120℃ for 2 minutes, aged at 60℃ for 24 hours, and then stored at 23℃ / 50%RH to obtain a solvent-based high-temperature resistant acrylic pressure-sensitive adhesive protective film.
[0027] Example 7 Example 7 is based on Example 6, and the amount of aluminum acetylacetone used in Example 7 is 0.8 parts.
[0028] Example 8 Example 8 is based on Example 6, and the amount of aluminum acetylacetone used in Example 8 is 1.1 parts.
[0029] Example 9 Example 9 is based on Example 6, and the amount of aluminum acetylacetone used in Example 9 is 1.4 parts.
[0030] Example 10 Example 10 is based on Example 6, and the amount of aluminum acetylacetone used in Example 10 is 1.7 parts.
[0031] Example 11 The heat-resistant monomer is maleimide, the initiator is benzoyl peroxide, and the curing agent is epoxide-modified m-phenylenediamine.
[0032] The composition of the high-temperature resistant acrylic prepolymer includes: 2 parts acrylic acid, 20 parts butyl acrylate, 65 parts isooctyl acrylate, 2 parts hydroxyethyl acrylate, 5 parts vinyl acetate, 0.8 parts benzoyl peroxide, 6 parts maleimide, 120 parts ethyl acetate, and 80 parts toluene.
[0033] The formulation of the solvent-based high-temperature resistant acrylic pressure-sensitive adhesive protective film includes 100 parts of high-temperature resistant acrylic prepolymer and 0.5 parts of epoxidized m-phenylenediamine.
[0034] S1. Preparation of high-temperature resistant acrylic prepolymer: After weighing and uniformly mixing monomers isooctyl acrylate, butyl acrylate, hydroxyethyl acrylate, vinyl acetate, acrylic acid, and maleimide, solution polymerization was carried out in a reactor equipped with nitrogen gas, a thermometer, and a reflux device. 0.4 parts of initiator, 80 parts of ethyl acetate, 50 parts of toluene, and two-thirds of the mixed monomers were added. The temperature was raised to 80°C and the reaction was maintained for 1 hour. The remaining mixed monomers, initiator, ethyl acetate, and toluene were added to the system through a constant pressure dropping funnel. The temperature was raised to 85°C and the reaction was maintained for 4 hours. After cooling, the material was discharged to obtain a pale yellow, transparent, high-temperature resistant acrylic prepolymer. S2. Preparation of solvent-based high-temperature resistant acrylic pressure-sensitive adhesive: High-temperature resistant acrylic prepolymer and epoxidized m-phenylenediamine were added to a mixing tank and stirred at 500 rpm for 30 minutes to obtain a mixture, which was then sealed and stored. S3. Preparation of solvent-based high-temperature resistant acrylic pressure-sensitive adhesive protective film: The mixture was evenly coated onto PI using a coater, cured at 120℃ for 2 minutes, aged at 60℃ for 24 hours, and then stored at 23℃ / 50%RH to obtain a solvent-based high-temperature resistant acrylic pressure-sensitive adhesive protective film.
[0035] Example 12 Example 12 is based on Example 11, and the amount of epoxidized m-phenylenediamine used in Example 12 is 0.8 parts.
[0036] Example 13 Example 13 is based on Example 11, and the amount of epoxidized m-phenylenediamine used in Example 13 is 1.1 parts.
[0037] Example 14 Example 14 is based on Example 11, and the amount of epoxidized m-phenylenediamine used in Example 14 is 1.4 parts.
[0038] Example 15 Example 15 is based on Example 11, and the amount of epoxidized m-phenylenediamine used in Example 15 is 1.7 parts.
[0039] Example 16 Example 16 is based on Example 10. In Example 16, a latent curing agent is introduced. In step S2, 0.5 parts of latent curing agent 3175 are added to the mixing tank.
[0040] Example 17 Example 17 is based on Example 10. In Example 17, a latent curing agent is introduced. In step S2, 1.0 parts of latent curing agent 3175 are added to the mixing tank.
[0041] Example 18 Example 18 is based on Example 10. In Example 18, a latent curing agent is introduced. In step S2, 1.5 parts of latent curing agent 3175 are added to the mixing tank.
[0042] Example 19 Example 19 is based on Example 10. In Example 19, a latent curing agent is introduced. In step S2, 3175 2.0 parts of latent curing agent are added to the mixing tank.
[0043] Example 20 Example 20 is based on Example 10. In Example 20, a latent curing agent is introduced. In step S2, 0.5 parts of latent curing agent 3575 are added to the mixing tank.
[0044] Example 21 Example 21 is based on Example 10. In Example 21, a latent curing agent is introduced. In step S2, 1.0 parts of latent curing agent 3575 are added to the mixing tank.
[0045] Example 22 Example 22 is based on Example 10. In Example 22, a latent curing agent is introduced. In step S2, 1.5 parts of latent curing agent 3575 are added to the mixing tank.
[0046] Example 23 Example 23 is based on Example 10. In Example 23, a latent curing agent is introduced. In step S2, 3575 2.0 parts of latent curing agent are added to the mixing tank.
[0047] Performance testing The performance of the solvent-based high-temperature resistant acrylic pressure-sensitive adhesive protective film prepared in various embodiments of the present invention was tested: (1) Infrared characterization: A small amount of high-temperature resistant acrylic prepolymer was dried at 85°C for 1 hour and measured using Shimadzu Fourier transform infrared spectroscopy. (2) 180° peel strength test: The substrates are steel plates and LCP plates (liquid crystal polymer plates). The test is conducted using a universal tensile testing machine, referring to GB / T 2792-2014. (3) Heat resistance test: Using an electric rolling roller tester, the 2kg roller was pressed back and forth twice on the steel plate at 600mm / min. After being placed in an oven and baked at high temperature for a certain period of time, it was placed in an environment of 23±1℃ and 50±5%RH and left to stand for 30 minutes. A universal tensile tester was used to peel it off at 180°. The residue of adhesive on the surface of the steel plate was observed and the test results were filled in Table 1.
[0048] Table 1. Heat resistance results of HDI curing and crosslinking in Examples 1-5 Testing items 180℃*1h 180℃*2h 180℃*4h 260℃*20min Example 1 Residual glue - - - Example 2 Edge glue overflow - - - Example 3 OK OK OK Residual glue Example 4 OK OK OK Edge glue overflow Example 5 OK OK OK Edge glue overflow Table 2. Heat resistance results of AlACA curing and crosslinking in Examples 6-10 Testing items 180℃*1h 180℃*2h 180℃*4h 260℃*20min Example 6 OK OK Edge glue overflow - Example 7 OK OK OK Residual glue Example 8 OK OK OK Edge glue overflow Example 9 OK OK OK Edge glue overflow Example 10 OK OK OK OK Table 3. Heat resistance results of GA-240 cured crosslinking in Examples 11-15 Testing items 180℃*1h 180℃*2h 180℃*4h 260℃*20min Example 11 OK OK OK Slight glue marks on the edges Example 12 OK OK OK OK Example 13 OK OK OK OK Example 14 OK OK OK OK Example 15 OK OK OK OK As shown in Table 1-3, increasing the amount of curing agent improves the high-temperature resistance of the pressure-sensitive adhesive. This is because increasing the amount of curing agent allows for a more complete cross-linking reaction in the pressure-sensitive adhesive, forming more cross-linking points and increasing the cross-linking density. Increased cross-linking density makes the molecular structure of the pressure-sensitive adhesive more compact and rigid, resulting in stronger interactions between molecular chains. This further restricts the movement of molecular chains at high temperatures, reducing the relaxation or breakage of molecular chains due to thermal motion, thereby lowering the coefficient of thermal expansion and increasing the thermal decomposition temperature.
[0049] Figure 1 This is the polymerization reaction formula of the high-temperature resistant acrylic prepolymer in Example 1 of this application.
[0050] Depend on Figure 2 It can be known that 2962cm -1 and 2873cm -1 The point is the stretching vibration of -CH2 and -CH3, 1462 cm. -1 The absorption peak for the bending vibration of -CH2 is 1378 cm⁻¹. 1 It is the symmetrical deformation vibration peak of -CH3, 1730 cm⁻¹ -1 It is the absorption peak of the stretching vibration of -C=O, at 1158 cm⁻¹. -1 and 1120cm -1 The peak at 1064 cm⁻¹ represents the asymmetric stretching vibration of -COC-. -1 The peak at 1600 cm⁻¹ represents the symmetrical stretching vibration of -COC-. -1 The absence of a C=C absorption peak indicates that the acrylic monomer has participated in the reaction and entered the main chain of the copolymer.
[0051] Depend on Figures 3-5 It is known that peel strength generally decreases with increasing curing agent dosage. This is because peel strength is determined by the interaction of wetting and cohesive strength, and wetting is a prerequisite for PSA to exhibit pressure sensitivity. Increasing the curing agent dosage increases the crosslinking density of the system, improves the cohesive strength of the pressure-sensitive adhesive, significantly reduces the wetting ability of the adhesive layer, and consequently lowers the peel strength. When the curing agent is hexamethylene diisocyanate, and the dosage is 0.8%, the peel strength reaches its peak value. At this point, the pressure-sensitive adhesive system exhibits good wetting properties and a certain modulus.
[0052] Depend on Figures 6-9 It is known that when a latent curing agent is added to the system, the peel strength of PSA on the steel plate increases under high temperature conditions, while the peel strength on the LCP plate decreases. The reason for this is the difference in the surface properties of the substrates. (1) The surface of the steel plate is relatively rough and has certain microscopic unevenness. Under high temperature conditions, PSA will flow and fill to a certain extent, which increases the contact area between the adhesive and the steel plate, increases the adhesion between the adhesive and the steel plate, and leads to an increase in peel strength. The surface of the LCP plate is relatively smooth, and the contact between PSA and the LCP plate is mainly achieved through physical interactions such as van der Waals forces between molecules in the initial stage. (2) The polar groups in PSA will form hydrogen bonds or coordination bonds with the metal atoms on the surface of the steel plate. This interaction is more stable after high temperature, and the peel strength is increased. (3) The latent curing agent undergoes a secondary crosslinking reaction at high temperature. The pressure-sensitive adhesive on the steel plate undergoes secondary crosslinking after high temperature, which increases the bonding force between the pressure-sensitive adhesive and the groove of the steel plate. When subjected to peel force, the pressure-sensitive adhesive can better resist deformation and breakage, thereby increasing the peel strength. The pressure-sensitive adhesive on the LCP board has a weaker interaction with the LCP board, and the cross-linked pressure-sensitive adhesive is more likely to detach from the surface of the LCP board, resulting in a decrease in peel strength.
[0053] This specific embodiment is merely an explanation of this application and is not intended to limit it. Based on the above description, those skilled in the art can make various changes and modifications without departing from the technical concept of this application. The technical scope of this application is not limited to the contents of the specification but must be determined according to the scope of the claims.
Claims
1. A solvent-based high-temperature resistant acrylic pressure-sensitive adhesive protective film, comprising a pressure-sensitive adhesive layer and a substrate layer, characterized in that: By weight, the pressure-sensitive adhesive layer comprises the following components: 1-5 parts acrylic acid, 10-30 parts butyl acrylate, 50-80 parts isooctyl acrylate, 1-5 parts hydroxyethyl acrylate, 1-10 parts vinyl acetate, 0.5-2 parts initiator, 1-10 parts heat-resistant monomer, 0.5-2 parts curing agent, 90-130 parts ethyl acetate, and 60-90 parts toluene.
2. The solvent-based high-temperature resistant acrylic pressure-sensitive adhesive protective film according to claim 1, characterized in that: The pressure-sensitive adhesive layer comprises the following components: 2 parts acrylic acid, 20 parts butyl acrylate, 65 parts isooctyl acrylate, 2 parts hydroxyethyl acrylate, 5 parts vinyl acetate, 0.8 parts initiator, 6 parts heat-resistant monomer, 0.5-1.7 parts curing agent, 120 parts ethyl acetate, and 80 parts toluene.
3. The solvent-based high-temperature resistant acrylic pressure-sensitive adhesive protective film according to claim 1, characterized in that: The substrate layer is 25PI, and the pressure-sensitive layer has a thickness of 20μm.
4. The solvent-based high-temperature resistant acrylic pressure-sensitive adhesive protective film according to claim 1, characterized in that: The heat-resistant monomer is either N-vinylcarbazole maleimide or N-vinylpyrrolidone.
5. The solvent-based high-temperature resistant acrylic pressure-sensitive adhesive protective film according to claim 1, characterized in that: The initiator is either benzoyl peroxide or azobisisobutyronitrile.
6. The solvent-based high-temperature resistant acrylic pressure-sensitive adhesive protective film according to claim 1, characterized in that: The curing agent is any one of hexamethylene diisocyanate, aluminum acetylacetonate, and m-phenylenediamine epoxide.
7. A method for preparing a solvent-based high-temperature resistant acrylic pressure-sensitive adhesive protective film according to any one of claims 1-6, characterized in that: Includes the following steps: S1. Preparation of high-temperature resistant acrylic prepolymer: The monomers isooctyl acrylate, butyl acrylate, hydroxyethyl acrylate, vinyl acetate, acrylic acid, and heat-resistant monomers are weighed and uniformly mixed to obtain a mixed monomer. The solution polymerization method is adopted. In the reaction vessel equipped with nitrogen gas, thermometer and reflux device, initiator, ethyl acetate, toluene and two-thirds of the mixed monomer are added. After heating, the reaction is maintained at the temperature. The remaining mixed monomer, initiator, ethyl acetate and toluene are added to the system through constant pressure dropping funnel. The temperature is continued to rise and the reaction is maintained at the temperature. After cooling, the material is discharged to obtain high temperature resistant acrylic prepolymer. S2. Preparation of solvent-based high-temperature resistant acrylic pressure-sensitive adhesive: High-temperature resistant acrylic prepolymer and curing agent are added to a mixing tank, stirred, and then the mixture is sealed and stored. S3. Preparation of solvent-based high-temperature resistant acrylic pressure-sensitive adhesive protective film: Using a coater, the mixture obtained in step S2 is uniformly coated onto PI, cured, aged, and stored to obtain a solvent-based high-temperature resistant acrylic pressure-sensitive adhesive protective film.