A silane modified flexible two-component polyurethane adhesive for OLED process protection and a preparation method and use method thereof

Abstract

This invention discloses a silane-modified flexible two-component polyurethane adhesive for OLED process protection, and its preparation and application methods, comprising a main agent, a curing agent, and a diluent; the main agent includes polyester polyol or polycarbonate polyol, polyether polyol, antistatic agent, α,ω-dihydroxypolydimethylsiloxane, isocyanate monomer, organic solvent, and catalyst; the curing agent includes isocyanate, polyether polyol, polydimethylsiloxane, small molecule polyol chain extender, defoamer, leveling agent, and organic solvent; the silane-modified flexible two-component polyurethane adhesive for OLED process protection provided by this invention, by bonding antistatic structural units and polysiloxane into the polyurethane molecular chain, results in a polyurethane protective adhesive with excellent antistatic properties, ultra-low peel strength, and good weather resistance, meeting the high-cleanliness and high-precision process standards of OLED.

Description

Technical Field

[0001] This invention relates to the field of adhesive technology, specifically to a silane-modified flexible two-component polyurethane adhesive for OLED process protection, and its preparation and application methods. Background Technology

[0002] With the rapid development of the electronics industry and the mobile internet sector, the market demand for mobile terminal devices such as smartphones and tablets continues to rise. OLED screens, with their core advantages of self-illumination, thinness, flexibility, and high contrast, have been widely used in terminal products such as smartphones, digital cameras, televisions, laptops, and automotive displays. The industry's annual growth rate exceeds 30%, and flexible OLED has become the mainstream development direction in the display field. As the OLED industry's technological iteration accelerates, the performance requirements for supporting protective materials in screen manufacturing processes are becoming increasingly stringent. Furthermore, OLED active materials are extremely sensitive to moisture and oxygen, leading to the gradual replacement of traditional glass and metal foil cover encapsulation methods. Plastic film substrates have become the preferred carrier for OLED encapsulation and process protection.

[0003] In the manufacturing process of OLED screens, the process protective film needs to be fully coated on the screen body throughout the entire process, playing a crucial role in transportation protection and laser cutting protection. Therefore, the matching adhesive must meet several stringent performance requirements: the peel strength must be less than 2gf / 25mm to ensure clean peeling without residue; it must have both low peel voltage and long-term stable antistatic properties, and no risk of small molecule migration and precipitation, avoiding electrostatic adsorption to contaminate the screen body and cause appearance defects; it must have excellent air venting properties to ensure bubble-free lamination; at the same time, it must have excellent temperature and weather resistance, and after long-term bonding and high-temperature process treatment, it can still be peeled off without residue, flakes, or powder, eliminating screen contamination.

[0004] Polyurethane adhesives have become the mainstream adhesive for protective films in OLED manufacturing processes due to their excellent air release properties, wettability, toughness, and adjustable mechanical properties. However, conventional polyurethane adhesives used in OLED manufacturing processes have shortcomings in performance synergy, making it difficult to simultaneously achieve core indicators such as antistatic durability, small molecule anti-exudation, and ultra-low peel force. Under harsh conditions such as high-temperature processes and laser cutting, they are prone to problems such as antistatic failure, adhesive layer exudation and contamination, and peeling residue powdering, failing to meet the high-cleanliness and high-precision process standards of high-end OLED screens.

[0005] Therefore, developing an adhesive for OLED process protection that combines excellent antistatic properties, ultra-low peel strength, and good weather resistance to meet the high cleanliness and high precision process standards of OLED is an urgent technical need and has significant industrial value. Summary of the Invention

[0006] To overcome the shortcomings of the existing technology, the present invention aims to provide a silane-modified flexible two-component polyurethane adhesive for OLED process protection, as well as its preparation and application methods. The adhesive has antistatic properties, ultra-low peel strength, and good weather resistance, solving problems such as easy residue removal during OLED protective film removal, high-temperature decomposition causing powder and slag shedding, and small molecule precipitation.

[0007] This invention is achieved through the following technical solution: In a first aspect, the present invention provides a silane-modified flexible two-component polyurethane adhesive for OLED process protection, comprising the following raw materials in parts by weight: 100 portions of the main ingredient, 3-20 parts of curing agent 30-50 parts of diluent.

[0008] Further, the main agent comprises the following raw material components in parts by weight: 10-50 parts of polyester polyol or polycarbonate polyol, 10-45 parts of polyether polyol, 2-10 parts of antistatic agent, 5-10 parts of α,ω-dihydroxypolydimethylsiloxane, 10-20 parts of isocyanate monomer, 10-40 parts of organic solvent, and 0.000003-0.00005 parts of catalyst; Further, the curing agent comprises the following raw material components in parts by weight: 100 parts isocyanate, 20-40 parts polyether polyol, 5-10 parts polydimethylsiloxane, 3-5 parts small molecule polyol chain extender, 0.1-2 parts defoamer, 0.1-2 parts leveling agent, and 30-80 parts organic solvent; Furthermore, the molar ratio of hydroxyl groups to isocyanate groups in the main agent is 1:(1.0~2.0). Further, the number average molecular weight of the polyester polyol is 500-3000; the number average molecular weight of the polycarbonate polyol is 1000-3000; and the number average molecular weight of the polyether polyol is 500-2000. Furthermore, the α,ω-dihydroxypolydimethylsiloxane has a number-average molecular weight of 500-5000; Furthermore, the antistatic agent has functional groups that can react with hydroxyl or isocyanate groups; Furthermore, the antistatic agent includes one or more of quaternary ammonium salt compounds, polyether amines, polyether block amides, and reactive ionic liquids; Further, the isocyanate monomer is one or more selected from hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, phenyldimethyl diisocyanate, toluene diisocyanate, and diphenylmethyl diisocyanate; Furthermore, the organic solvent is one or more of toluene, xylene, ethyl acetate, acetone, and butanone; Furthermore, the catalyst is one or two of organobismuth catalysts and organotin catalysts; Furthermore, the polyether polyol includes, but is not limited to, one or more of polyethylene oxide glycol with a number average molecular weight of 500-2000 and / or one or more of polytetrahydrofuran with a number average molecular weight of 500-2000 and / or one or more of polypropylene glycol with a number average molecular weight of 500-2000. Furthermore, the polyester polyol is formed by the polycondensation of terephthalic acid, isophthalic acid, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, fumaric acid, maleic acid, 1,4-cyclohexanedicarboxylic acid, malonic acid, succinic anhydride, adipic acid, sebacic acid, lauryl acid, neopentyl glycol, ethylene glycol, diethylene glycol, 1,2-propanediol, 1,6-hexanediol, 2-methyl-1,3-propanediol, 2-butylethyl-propanediol, 1,4-dihydroxymethylcyclohexane, hydrogenated bisphenol A, 1,4-butanediol, 2,2,4-trimethyl-1,3-pentanediol, neopentyl glycol monoester of hydroxypentanoic acid, trimethylolpropane, glycerol, and trimethylolethane. Further, the polyester polyol is preferably poly(1,4-butanediol adipate) with a number average molecular weight of 2000; Furthermore, the isocyanate is one or both of toluene diisocyanate trimer and hexamethylene diisocyanate trimer; Furthermore, the small molecule polyol chain extender is one or more selected from diethylene glycol, dipropylene glycol, 1,4-butanediol, glycerol, and trimethylolpropane; Furthermore, the diluent is one or more of toluene, ethyl acetate, acetone, and butanone.

[0009] Secondly, the present invention also provides a method for preparing the silane-modified flexible two-component polyurethane adhesive for OLED process protection, comprising the following steps: S1. Preparation of the main agent: Polyester polyol or polycarbonate polyol, polyether polyol are added to a reaction vessel and heated to 100℃~120℃ to remove water for 2~3 hours. The temperature is then lowered to 70-90℃, and isocyanate and catalyst are added and reacted for 2~4 hours. An antistatic agent and α,ω-dihydroxypolydimethylsiloxane are added, and the reaction continues at 70-90℃ for 2~4 hours. The temperature is then lowered to 50-70℃, organic solvent is added, and the mixture is stirred evenly. The main agent is then discharged. S2. Preparation of curing agent: After reacting isocyanate with polyether polyol, polydimethylsiloxane and small molecule polyol at 60~90℃ for 1~4 hours, the temperature is lowered to 40℃~50℃, organic solvent, defoamer and leveling agent are added, and the mixture is stirred evenly. The curing agent is then discharged. S3, Adhesive compounding: After the main agent, curing agent and diluent are mixed evenly, a liquid adhesive is prepared, which is the polyurethane adhesive.

[0010] Thirdly, the present invention also provides a method for using the silane-modified flexible two-component polyurethane adhesive for OLED process protection, comprising the following steps: (I) The polyurethane adhesive is uniformly coated onto the PET film; (II) After drying in the drying tunnel, it is then laminated with a release film and wound up to obtain a protective film for OLED manufacturing process; (III) Place the protective film obtained in step (II) in an oven at 30-60°C for curing and then cool it to room temperature. The curing time is 24-96 hours.

[0011] The present invention has the following beneficial effects: The silane-modified flexible two-component polyurethane adhesive for OLED process protection provided by this invention achieves durable and stable antistatic properties by chemically bonding antistatic structural units into the polyurethane main agent molecular chain, effectively avoiding the problem of small molecule migration and precipitation. Furthermore, it creatively employs α,ω-dihydroxypolydimethylsiloxane to copolymerize and modify the polyurethane main agent, significantly reducing peel strength while simultaneously improving the system's heat resistance. In addition, through structural design and formulation optimization of the curing agent, the final two-component polyurethane protective adhesive maintains low peel strength, low tear voltage, and excellent temperature resistance, while effectively suppressing powder and residue generation during laser cutting and subsequent transport, fully meeting the stringent cleanliness requirements of OLED processes. Detailed Implementation

[0012] The following embodiments are provided to better understand the present invention and are not limited to the preferred embodiments described. They do not constitute a limitation on the content and scope of protection of the present invention. Any product that is the same as or similar to the present invention, derived by any person under the guidance of the present invention or by combining the features of the present invention with other prior art, falls within the protection scope of the present invention.

[0013] For experiments not specifically described in the examples, the procedures or conditions should be followed according to the conventional experimental procedures described in the literature in this field. Reagents or instruments whose manufacturers are not specified are all commercially available conventional reagent products.

[0014] Unless otherwise specified, the temperature in the embodiments of the present invention is room temperature or ambient temperature; room temperature or ambient temperature refers to 25±1℃.

[0015] All raw materials used in this invention can be prepared in-house or purchased from the market.

[0016] Example 1 of main agent synthesis A polyester polyol with a number average molecular weight of 2000 (prepared by reacting adipic acid with 1,4-butanediol) and polypropylene glycol with a number average molecular weight of 2000 (PPG 2000) were mixed evenly and heated to dissolve. The mixture was heated to 120°C and dehydrated for 2 hours under a vacuum of less than 100 Pa. The mixture was then cooled to 70°C, and polyphosphoric acid was added and stirred for 10 minutes. 4,4'-diphenylmethane diisocyanate and bismuth neodecanoate were added, and the mixture was stirred and reacted for 2 hours under a vacuum of less than 100 Pa and a reaction temperature of 70°C. An antistatic agent (hydroxyethyl alkyl quaternary ammonium salt) and α,ω-dihydroxy polydimethylsiloxane (Wacker WD90) were added, and the mixture was reacted for another 2 hours at 70°C. The mixture was then cooled to 50°C, and ethyl acetate was added as solvent. The mixture was stirred evenly, and the product was discharged to obtain the main agent.

[0017] In the above process, the amount of 4,4'-diphenylmethane diisocyanate is 15 parts, the amount of polyester polyol is 46 parts, the amount of PPG-2000 is 12 parts, the amount of bismuth neodecanoate is 200 ppm, the amount of antistatic agent is 2 parts, the amount of α,ω-dihydroxypolydimethylsiloxane is 8 parts, the amount of polyphosphoric acid is 0.01 parts, and the amount of ethyl acetate is 15 parts.

[0018] Example 2 of main agent synthesis Polytetrahydrofuran (PTMG 2000) with a number average molecular weight of 2000 and polycarbonate diol (PCDL 2000) with a number average molecular weight of 2000 were mixed evenly and heated to dissolve. The temperature was raised to 120°C and dehydrated for 2 hours under a vacuum of less than 100 Pa. The temperature was then lowered to 70°C, polyphosphoric acid was added, and the reaction was carried out for 10 minutes. 4,4'-diphenylmethane diisocyanate and bismuth neodecanoate were added, and the reaction was stirred for 2 hours under a vacuum of less than 100 Pa and a reaction temperature of 70°C. An antistatic agent (hydroxyethyl alkyl quaternary ammonium salt) and α,ω-dihydroxypolydimethylsiloxane (Wacker WD90) were added, and the reaction was continued at 70°C for 2 hours. The temperature was lowered to 50°C, ethyl acetate solvent was added, and the mixture was stirred evenly. The product was then discharged to obtain the main agent.

[0019] In the above process, the dosage of 4,4'-diphenylmethane diisocyanate was 15 parts, the dosage of PTMG 2000 was 35 parts, the dosage of PCDL-2000 was 23 parts, the dosage of bismuth neodecanoate was 200 ppm, the dosage of antistatic agent was 2 parts, the dosage of α,ω-dihydroxypolydimethylsiloxane was 8 parts, the dosage of polyphosphoric acid was 0.01 parts, and the dosage of ethyl acetate was 15 parts.

[0020] Example 3 of main agent synthesis A polyester polyol with a number average molecular weight of 1000 (formed by the reaction of isophthalic acid, adipic acid and diethylene glycol) and polypropylene glycol (PPG 2000) and polytetrahydrofuran (PTMG 2000) with a number average molecular weight of 2000 were mixed evenly and heated to dissolve. The mixture was heated to 120°C and dehydrated for 2 hours under a vacuum of less than 100 Pa. The mixture was then cooled to 70°C, and polyphosphoric acid was added and stirred for 10 minutes. 4,4'-diphenylmethane diisocyanate and bismuth neodecanoate were added, and the mixture was stirred and reacted for 2 hours under a vacuum of less than 100 Pa and a reaction temperature of 70°C. An antistatic agent (hydroxyethyl alkyl quaternary ammonium salt) and α,ω-dihydroxypolydimethylsiloxane (Wacker WD90) were added, and the mixture was reacted for another 2 hours at 70°C. The mixture was then cooled to 50°C, and ethyl acetate was added as solvent. The mixture was mixed evenly, and the product was discharged to obtain the main agent.

[0021] In the above process, the following amounts were used: 15 parts of 4,4'-diphenylmethane diisocyanate, 36 parts of polyester polyol, 10 parts of PTMG-2000, 12 parts of PPG-2000, 200 ppm of bismuth neodecanoate, 2 parts of antistatic agent, 8 parts of α,ω-dihydroxypolydimethylsiloxane, 0.01 parts of polyphosphoric acid, and 15 parts of ethyl acetate.

[0022] Example 4 of main agent synthesis A polyester polyol with a number average molecular weight of 1000 (formed by reacting isophthalic acid, adipic acid, and diethylene glycol) was mixed evenly with polypropylene glycol (PPG 2000) and polytetrahydrofuran (PTMG 2000) with an average molecular weight of 2000. The mixture was heated to dissolve the polyol and heated to 120°C. Under a vacuum of less than 100 Pa, the polyol was dehydrated for 2 hours. The mixture was then cooled to 70°C, and polyphosphoric acid was added and stirred for 10 minutes. 4,4'-diphenylmethane diisocyanate and bismuth neodecanoate were added, and the mixture was stirred and reacted for 2 hours under a vacuum of less than 100 Pa and a reaction temperature of 70°C. An antistatic agent (hydroxyethyl alkyl quaternary ammonium salt) and α,ω-dihydroxypolydimethylsiloxane (Wacker WD90) were added, and the mixture was reacted for another 2 hours at 70°C. The mixture was then cooled to 50°C, and ethyl acetate was added as solvent. The mixture was stirred evenly, and the product was discharged to obtain the main agent.

[0023] In the above process, the following amounts were used: 15 parts of 4,4'-diphenylmethane diisocyanate, 16 parts of polyester polyol, 20 parts of PTMG-2000, 22 parts of PPG-2000, 200 ppm of bismuth neodecanoate, 2 parts of antistatic agent, 8 parts of α,ω-dihydroxypolydimethylsiloxane, 0.01 parts of polyphosphoric acid, and 15 parts of ethyl acetate.

[0024] Example 5 of main agent synthesis The only difference between it and Example 1 of the main agent synthesis is that α,ω-dihydroxypolydimethylsiloxane was not added.

[0025] Example 6 of main agent synthesis A polyester polyol with a number average molecular weight of 2000 (prepared by reacting adipic acid with 1,4-butanediol) and polypropylene glycol with a number average molecular weight of 2000 (PPG 2000) were mixed evenly and heated to dissolve. The mixture was heated to 120°C and dehydrated for 2 hours under a vacuum of less than 100 Pa. The mixture was then cooled to 70°C, and polyphosphoric acid was added and stirred for 10 minutes. 4,4'-diphenylmethane diisocyanate and bismuth neodecanoate were added, and the mixture was stirred and reacted for 2 hours under a vacuum of less than 100 Pa and a reaction temperature of 70°C. A migratory antistatic agent (quaternary ammonium salt) and α,ω-dihydroxypolydimethylsiloxane (Wacker WD90) were added, and the mixture was reacted for another 2 hours at 70°C. The mixture was then cooled to 50°C, and ethyl acetate was added as solvent. The mixture was stirred evenly, and the product was discharged to obtain the main agent.

[0026] In the above process, the amount of 4,4'-diphenylmethane diisocyanate is 15 parts, the amount of polyester polyol is 46 parts, the amount of PPG-2000 is 12 parts, the amount of bismuth neodecanoate is 200 ppm, the amount of antistatic agent is 2 parts, the amount of α,ω-dihydroxypolydimethylsiloxane is 8 parts, the amount of polyphosphoric acid is 0.01 parts, and the amount of ethyl acetate is 15 parts.

[0027] Example 1 of Curing Agent Synthesis The trimer of hexamethylene diisocyanate (Covestro N3300) was reacted with polyether polyol (PPG2000) with a number average molecular weight of 2000, polydimethylsiloxane (Dow PMX-200), and trimethylolpropane at 90°C for 3 hours. The mixture was then cooled to 50°C and ethyl acetate solvent, defoamer (BYK-088), and leveling agent (BYK-333) were added and stirred until homogeneous to obtain curing agent 1.

[0028] In the above process, the amount of hexamethylene diisocyanate trimer is 100 parts, the amount of PPG2000 is 20 parts, the amount of polydimethylsiloxane is 5 parts, the amount of trimethylolpropane is 4 parts, the amount of defoamer is 2 parts, the amount of leveling agent is 2 parts, and the amount of ethyl acetate is 40 parts.

[0029] Example 2 of curing agent synthesis: Trimer of commercially available hexamethylene diisocyanate (Covestro N3300) Curing agent synthesis example 3: Compared with curing agent synthesis example 1, no polydimethylsiloxane was added, and everything else remained the same. Example

[0030] Preparation of a silane-modified flexible two-component polyurethane adhesive for OLED process protection: The formulation consists of the following components by weight: 100 parts main agent (from main agent synthesis example 1), 6 parts curing agent (from curing agent synthesis example 1), and 35 parts ethyl acetate (diluent). During preparation, all components are stirred thoroughly and allowed to stand for 20 minutes until all bubbles disappear, thus obtaining the silane-modified flexible two-component polyurethane adhesive for OLED process protection. Example

[0031] Preparation of a silane-modified flexible two-component polyurethane adhesive for OLED process protection: The formulation consists of the following components by weight: 100 parts main agent (from main agent synthesis example 2), 6 parts curing agent (from curing agent synthesis example 1), and 35 parts ethyl acetate (diluent). During preparation, all components are stirred thoroughly and allowed to stand for 20 minutes until all bubbles disappear, thus obtaining the silane-modified flexible two-component polyurethane adhesive for OLED process protection. Example

[0032] Preparation of a silane-modified flexible two-component polyurethane adhesive for OLED process protection: The formulation consists of the following components by weight: 100 parts main agent (from main agent synthesis example 3), 6 parts curing agent (from curing agent synthesis example 1), and 35 parts ethyl acetate (diluent). During preparation, all components are stirred thoroughly and allowed to stand for 20 minutes until all bubbles disappear, thus obtaining the silane-modified flexible two-component polyurethane adhesive for OLED process protection. Example

[0033] Preparation of a silane-modified flexible two-component polyurethane adhesive for OLED process protection: The formulation consists of the following components by weight: 100 parts main agent (from main agent synthesis example 4), 6 parts curing agent (from curing agent synthesis example 1), and 35 parts ethyl acetate (diluent). During preparation, all components are stirred thoroughly and allowed to stand for 20 minutes until all bubbles disappear, thus obtaining the silane-modified flexible two-component polyurethane adhesive for OLED process protection.

[0034] Comparative Example 1 The curing agent in Example 1 was replaced with that in Example 2, while everything else remained the same.

[0035] Comparative Example 2 The main agent in Example 1 was replaced with the main agent synthesis example 5, while everything else remained unchanged.

[0036] Comparative Example 3 The main agent in Example 1 was replaced with the main agent synthesis example 6, while everything else remained unchanged.

[0037] Comparative Example 4 The curing agent in Example 1 was replaced with that in Example 3, while everything else remained the same.

[0038] Sample preparation: The adhesives prepared in Examples 1-4 and Comparative Examples 1-4 were evenly coated on a PET film using a coating laminator, dried in a drying oven, then laminated with a release film, wound up, and placed in an oven at 60 °C for 36 h for curing. After cooling to room temperature, the protective films for OLED processes were obtained and ready for testing.

[0039] Testing methods: (1)Transmittance test Referring to the standard GB / T 2410-2008, the transmittance of the protective film sample adhered to the substrate was directly measured using a haze meter.

[0040] (2)Peel strength test The protective film was cut into specimens with dimensions of 300 mm × 25 mm, and the release film was peeled off and evenly adhered to the surface of a clean polarizer. Subsequently, a universal testing machine was used to conduct a peel strength test under standard conditions of a peel angle of 180° and a tensile speed of 300 mm / min.

[0041] (3)Peeling voltage During the test, the protective film was cut into strips with dimensions of 150 mm × 50 mm, the release film was peeled off and adhered to a clean glass plate. Subsequently, the protective film was peeled off at a peel angle of 180° and a speed of 30 mm / min, and the residual static voltage on the glass surface after peeling was immediately measured using a SIMCO FMX-003 electrostatic field tester.

[0042] (4)Double 85 aging test The protective film was cut into strips with dimensions of 300 mm × 25 mm, the release film was peeled off, and its adhesive surface was evenly adhered to a glass substrate. Subsequently, the specimen was placed in a programmable thermostatic and humid test chamber for an accelerated aging test for 168 hours in an environment of 85 °C and 85% relative humidity. After the test, observations were made. If no wrinkles, detachment, chipping, or whitening occurred on the protective film, its weather resistance was judged to be qualified; otherwise, if any of the above defects occurred, it was judged to be unqualified.

[0043]

[0044] According to Examples 1-4 and Comparative Examples 1-4, the protective adhesives prepared in Examples 1-4 had low peel strength, good antistatic properties (low peeling voltage), high transmittance, and good heat resistance (passing the double 85 test), with excellent overall performance, and Example 1 was the best among them.

[0045] As can be seen from Example 1 compared with Comparative Examples 1 and 4, the present invention achieves low peel force and good antistatic properties (low peel voltage) of the protective film by introducing a soft and hard segment microphase structure into the curing agent. A comparison of Example 1 and Comparative Example 2 shows that the introduction of siloxane segments into the main agent in this invention can synergistically reduce peeling force, improve antistatic properties (low peeling voltage), and improve temperature resistance. As can be seen from the comparison between Example 1 and Comparative Example 3, the present invention not only endows the material with durable and stable antistatic properties (low peel voltage) by chemically bonding the antistatic unit to the main agent, but also improves the thermal stability through structural regularity, thereby ensuring that the interface remains intact and free from flaking defects even under the harsh aging conditions of double 85.

[0046] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A silane-modified flexible two-component polyurethane adhesive for OLED process protection, characterized in that, Including the following parts by weight of raw materials: 100 portions of the main ingredient, 3-20 parts of curing agent 30-50 parts diluent; The main agent comprises the following raw material components in parts by weight: 10-50 parts of polyester polyol or polycarbonate polyol, 10-45 parts of polyether polyol, 2-10 parts of antistatic agent, 5-10 parts of α,ω-dihydroxypolydimethylsiloxane, 10-20 parts of isocyanate monomer, 10-40 parts of organic solvent, and 0.000003-0.00005 parts of catalyst; The curing agent comprises the following raw material components in parts by weight: 100 parts isocyanate, 20-40 parts polyether polyol, 5-10 parts polydimethylsiloxane, 3-5 parts small molecule polyol chain extender, 0.1-2 parts defoamer, 0.1-2 parts leveling agent, and 30-80 parts organic solvent.

2. The silane-modified flexible two-component polyurethane adhesive for OLED process protection according to claim 1, characterized in that, The number average molecular weight of the polyester polyol is 500-3000; the number average molecular weight of the polycarbonate polyol is 1000-3000; the number average molecular weight of the polyether polyol is 500-2000; and the number average molecular weight of the α,ω-dihydroxypolydimethylsiloxane is 500-5000.

3. The silane-modified flexible two-component polyurethane adhesive for OLED process protection according to claim 2, characterized in that, The polyether polyol includes one or more of polyethylene oxide glycol with a number average molecular weight of 500 to 2000 and / or one or more of polytetrahydrofuran with a number average molecular weight of 500 to 2000 and / or one or more of polypropylene glycol with a number average molecular weight of 500 to 2000. The polyester polyol is formed by the polycondensation of terephthalic acid, isophthalic acid, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, fumaric acid, maleic acid, 1,4-cyclohexanedicarboxylic acid, malonic acid, succinic anhydride, adipic acid, sebacic acid, lauryl acid, neopentyl glycol, ethylene glycol, diethylene glycol, 1,2-propanediol, 1,6-hexanediol, 2-methyl-1,3-propanediol, 2-butylethyl-propanediol, 1,4-dihydroxymethylcyclohexane, hydrogenated bisphenol A, 1,4-butanediol, 2,2,4-trimethyl-1,3-pentanediol, neopentyl glycol monoester of hydroxypentanoic acid, trimethylolpropane, glycerol, and trimethylolethane.

4. The silane-modified flexible two-component polyurethane adhesive for OLED process protection according to claim 1, characterized in that, The antistatic agent has functional groups that can react with hydroxyl or isocyanate groups; The isocyanate monomer is one or more selected from hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, phenyldimethyl diisocyanate, toluene diisocyanate, and diphenylmethyl diisocyanate; The organic solvent is one or a mixture of more than one of toluene, xylene, ethyl acetate, acetone, and butanone; The catalyst is one or both of organobismuth catalysts and organotin catalysts.

5. The silane-modified flexible two-component polyurethane adhesive for OLED process protection according to claim 4, characterized in that, The antistatic agent includes one or more of quaternary ammonium salt compounds, polyetheramines, polyether block amides, and reactive ionic liquids.

6. The silane-modified flexible two-component polyurethane adhesive for OLED process protection according to claim 1, characterized in that, The isocyanate is one or both of toluene diisocyanate trimer and hexamethylene diisocyanate trimer; The small molecule polyol chain extender is one or more of diethylene glycol, dipropylene glycol, 1,4-butanediol, glycerol, and trimethylolpropane.

7. The silane-modified flexible two-component polyurethane adhesive for OLED process protection according to claim 1, characterized in that, The diluent is one or more of toluene, ethyl acetate, acetone, and butanone.

8. The method for preparing the silane-modified flexible two-component polyurethane adhesive for OLED process protection according to any one of claims 1-7, characterized in that, Includes the following steps: S1. Preparation of the main agent: Polyester polyol or polycarbonate polyol, polyether polyol are added to a reaction vessel and heated to 100℃~120℃ to remove water for 2~3 hours. The temperature is then lowered to 70-90℃, and isocyanate and catalyst are added and reacted for 2~4 hours. An antistatic agent and α,ω-dihydroxypolydimethylsiloxane are added, and the reaction continues at 70-90℃ for 2~4 hours. The temperature is then lowered to 50-70℃, organic solvent is added, and the mixture is stirred evenly. The main agent is then discharged. S2. Preparation of curing agent: After reacting isocyanate with polyether polyol, polydimethylsiloxane and small molecule polyol at 60~90℃ for 1~4 hours, the temperature is lowered to 40℃~50℃, organic solvent, defoamer and leveling agent are added, and the mixture is stirred evenly. The curing agent is then discharged. S3, Adhesive compounding: After the main agent, curing agent and diluent are mixed evenly, a liquid adhesive is prepared, which is the polyurethane adhesive.

9. The method of using the silane-modified flexible two-component polyurethane adhesive for OLED process protection according to any one of claims 1-7, characterized in that, Includes the following steps: (I) The polyurethane adhesive is uniformly coated onto the PET film; (II) After drying in the drying tunnel, it is then laminated with a release film and wound up to obtain a protective film for OLED manufacturing process; (III) Place the protective film obtained in step (II) in an oven at 30-60°C for curing and then cool it to room temperature. The curing time is 24-96 hours.

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