Flexible UV curing high-temperature-resistant adhesive as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of adhesives, and relates to a flexible UV-cured high-temperature-resistant adhesive as well as a preparation method and application thereof. After being cured, the flexible UV curing high-temperature-resistant adhesive can keep certain flexibility and is mainly applied to adhesion of elastic base materials such as pebax, TPU and TPE; according to the invention, glycidyl and a modified acrylic acid precursor are subjected to ring-opening polymerization, polycaprolactone is introduced, a stable three-dimensional network structure is constructed, and the obtained flexible UV-cured high-temperature-resistant adhesive has good adhesive property and damage resistance; the nano calcium carbonate is added to endow the flexible UV-cured high-temperature-resistant adhesive with good waterproof performance, and the hydrogenated castor oil is added to further improve the thixotropy and flexibility of the flexible UV-cured high-temperature-resistant adhesive, so that the flexible UV-cured high-temperature-resistant adhesive can be applied to more scenes.

Description

Technical Field

[0001] The invention relates to the technical field of adhesives, and in particular to a flexible UV-curable high-temperature-resistant adhesive and a preparation method and application thereof. Background Art

[0002] UV adhesives use ultraviolet rays to initiate polymerization reactions to achieve rapid bonding of materials. With the continuous advancement of photochemical technology, the performance of UV adhesives has been continuously optimized, gradually moving from laboratories to industrial applications, and are widely used in electronics, medical, automotive manufacturing and other industries.

[0003] Flexible UV curing adhesives have excellent bonding properties and better flexibility compared to traditional UV adhesives. They are suitable for bonding elastic substrates, especially in applications where the structure is required to bend, stretch or deform. Flexible UV curing adhesives can remain flexible after being cured by UV light, without affecting the functions of the substrate and the bonding structure, and also play a certain role in buffering and shock absorption when bonding elastic materials. However, the heat resistance temperature of flexible UV curing adhesives is usually between 80 and 120°C. Specially formulated flexible UV curing adhesives can withstand higher temperatures, but usually not exceeding 150°C.

[0004] The patent application with publication number CN109294511A discloses a UV curing adhesive suitable for bonding flexible substrates. The technical solution uses a polyurethane acrylate prepolymer and a tackifying resin. The tackifying resin formed by the polymerization of vinyl acetate, butyl acrylate and isooctyl acrylate will become hard and brittle in a low temperature environment, thereby reducing the flexibility and adhesion of the adhesive, affecting its bonding effect on the flexible substrate in a low temperature environment. In addition, photoinitiators such as bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide and 2,4,6-trimethylbenzoyldiphenylphosphine oxide will be affected by the thickness of the adhesive when absorbing ultraviolet rays to initiate curing. If the adhesive layer is thick, ultraviolet rays may not be able to fully penetrate, resulting in incomplete internal curing, thereby affecting the overall bonding performance and weather resistance. Summary of the invention

[0005] The present application aims to provide a flexible UV-curable high temperature resistant adhesive and its preparation method and application. The flexible UV-curable high temperature resistant adhesive has strong bonding performance, can be quickly cured under UV light, has good high temperature resistance and waterproof and oil-proof properties, and at the same time, the adhesive can maintain good flexibility after curing, and is used for bonding elastic substrates such as pebax, TPU, and TPE.

[0006] To achieve the above object, the present invention provides a flexible UV curing high temperature resistant adhesive, which comprises a main agent, nano calcium carbonate, hydrogenated castor oil, an inhibitor, an antioxidant, a surfactant and a photoinitiator, wherein the mass ratio of the main agent, nano calcium carbonate, hydrogenated castor oil, inhibitor, antioxidant, surfactant and photoinitiator is 1: (0.1-0.15): (0.1-0.3): (0.1-0.5): (0.1-0.5): (0.02-0.05): (0.05-0.1); the structural formula of the main agent is as follows: , Wherein, in the main agent structural formula, n is an integer between 1 and 10, α is an integer between 1 and 10, and β is an integer between 1 and 10, and α and β can be the same value or different values.

[0007] The present invention also provides a method for preparing a flexible UV-curable high temperature resistant adhesive, comprising: Step S1, adding polycaprolactone and maleic anhydride into a first solvent to dissolve, adding a catalyst, reacting to obtain a crude active macromolecular monomer product, and subjecting the crude product to reduced pressure distillation and drying to obtain an active macromolecular monomer; Step S2, adding the active macromolecular monomer and the acrylic acid monomer into a second solvent to dissolve, adding an initiator, and reacting to obtain a block copolymer; Step S3, mixing glycidol and the block copolymer, adding a catalyst, and reacting to obtain a main agent; Step S4, mixing the main agent with nano calcium carbonate, adding hydrogenated castor oil, polymerization inhibitor, antioxidant, surfactant and photoinitiator, and stirring to obtain a flexible UV curable high temperature resistant adhesive.

[0008] Preferably, in step S1, the first solvent is any one or more of toluene, acetonitrile, xylene, and N,N'-dimethylformamide.

[0009] Preferably, in step S1, the catalyst is any one or more of p-toluenesulfonic acid, methanesulfonic acid, scandium trifluoromethanesulfonate, and N,N'-dimethylaminopyridine.

[0010] Preferably, in step S1, the mass ratio of the polycaprolactone, maleic anhydride, the first solvent and the catalyst is 1:(1.1-1.5):(4-5):(0.03-0.05).

[0011] Preferably, in step S1, the reaction temperature is 100-150° C., and the reaction time is 5-8 h.

[0012] Preferably, in step S1, the temperature of the reduced pressure distillation is 80-90° C., and the time is 10-30 min.

[0013] Preferably, in step S1, the drying temperature is 60-70° C., and the drying time is 10-12 hours.

[0014] Preferably, in step S2, the second solvent is any one or more of dichloromethane, tetrahydrofuran, and toluene.

[0015] Preferably, in step S2, the initiator is any one or more of azobisisobutyronitrile, ammonium persulfate, potassium persulfate, and tert-butyl perbenzoate.

[0016] Preferably, in step S2, the acrylic acid monomer is any one or more of ethyl acrylate, butyl acrylate, isooctyl acrylate, and lauryl acrylate.

[0017] Preferably, in step S2, the mass ratio of the active macromolecular monomer, the acrylic acid monomer, the second solvent and the initiator is 1:(0.2-0.4):(4-5):(0.05-0.1).

[0018] Preferably, in step S2, the reaction temperature is 60-90° C., and the reaction time is 4-8 h.

[0019] Preferably, in step S3, the catalyst is any one or more of sulfuric acid, hydrochloric acid, perchloric acid, and phosphoric acid.

[0020] Preferably, in step S3, the mass ratio of glycidol, block copolymer and catalyst is 1:(2-5):(0.05-0.2).

[0021] Preferably, in step S3, the reaction temperature is 50-90° C., and the reaction time is 3-8 h.

[0022] Preferably, in step S4, the inhibitor is any one or more of N-nitroso-N-phenylhydroxylamine aluminum, 2,4-dimethyl-6-tert-butylphenol, and p-hydroxyanisole.

[0023] Preferably, in step S4, the antioxidant is any one or more of 2,2'-methylenebis(4-methyl-6-tert-butylphenol), tris(2,4-di-tert-butylphenyl)phosphite, and 2,6-di-tert-butyl-4-methylphenol.

[0024] Preferably, in step S4, the surfactant is any one or more of sodium alkylbenzene sulfonate, fatty alcohol polyoxyethylene ether, cocamidopropyl betaine, and cetyltrimethylammonium bromide; the photoinitiator is a free radical photoinitiator, including any one or more of 1-hydroxycyclohexyl phenyl ketone, benzoin dimethyl ether, 2-hydroxy-2-methyl-1-phenyl-1-propanone, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, and bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide.

[0025] Preferably, in step S4, the stirring temperature is 30-60° C., and the stirring time is 1-3 h.

[0026] The present invention also provides application of the flexible UV curing high temperature resistant adhesive in bonding elastic substrates such as pebax, TPU, TPE, etc.

[0027] Impurities or incompletely reacted raw materials generated during the preparation of the main agent have no significant effect on the performance of the adhesive; if necessary, it can be purified by conventional purification means in the art.

[0028] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) The flexible UV-curable high-temperature-resistant adhesive prepared by the present invention has good flexibility after curing and is suitable for bonding elastic substrates such as pebax, TPU, and TPE. The present invention adopts glycidol and modified acrylic acid precursor ring-opening polymerization, introduces polycaprolactone, and constructs a stable three-dimensional network structure, wherein the introduction of polycaprolactone can increase the flexibility of the entire molecular chain, and the main chain structure formed by the ring-opening polymerization of glycidol and modified acrylic acid precursor, under the action of polycaprolactone, its rigid part is separated and diluted by the flexible polycaprolactone segment, further improving the overall flexibility of the molecular chain, so that the adhesive can better fit the flexible substrate, when the substrate is bent, stretched, etc., the adhesive can also be deformed without brittle cracking, and maintain good bonding performance; in addition, polycaprolactone also plays the role of an internal plasticizer, which can reduce the interaction force between the molecular chains of the adhesive, making it easier to slide between the molecular chains, and compared with traditional external plasticizers, the internal plasticizer will not migrate out of the adhesive system due to the passage of time or environmental factors, so that the flexibility of the adhesive can be maintained for a long time and stably. This allows the flexible UV-cured high temperature resistant adhesive to maintain good flexibility under different use environments and time conditions, and adapt to various dynamic changes of the flexible substrate.

[0029] (2) The flexible UV-curable high-temperature resistant adhesive prepared by the present invention has good high performance resistance. The epoxy groups with high reactivity in glycidol react with the active groups in the modified acrylic precursor during the ring-opening polymerization to form a cross-linked structure. This cross-linked structure is like building many "bridges" between the molecular chains, making it difficult for the molecular chains to slide and deform relative to each other at high temperatures, thereby improving the high-temperature resistance of the adhesive. The introduction of polycaprolactone interacts with the cross-linked network formed by glycidol and the modified acrylic precursor, making the cross-linked structure more complete and stable. The polycaprolactone chain segment plays a supporting and regulating role in the cross-linked network, further enhancing the stability of the cross-linked structure and improving the adhesive's ability to resist deformation at high temperatures.

[0030] (3) The flexible UV-curable high-temperature resistant adhesive prepared by the present invention contains nano-calcium carbonate and hydrogenated castor oil. The nano-calcium carbonate has a small particle size and a large specific surface area, and can produce a good interface interaction with the adhesive matrix. When added to the flexible UV-curable high-temperature resistant adhesive, it can improve its waterproof and oil-proof properties and wear resistance without reducing the transparency of the adhesive, and can also improve the processing performance and stability of the adhesive. The addition of hydrogenated castor oil can improve the thixotropy of the adhesive, that is, the viscosity of the adhesive will decrease when subjected to shear force, which is convenient for coating and construction. When the shear force disappears, the viscosity can be increased again. Rapid recovery prevents the adhesive from sagging or deformation after coating, making the adhesive more convenient to operate during construction. It also helps to control the amount and shape of the adhesive and improve the accuracy and efficiency of bonding. Hydrogenated castor oil has good wetting properties and contains a large number of saturated fatty acid segments in its molecular chain. These segments have good flexibility and can be integrated into the molecular network of the adhesive as a flexible segment, so that the adhesive can better adapt to the deformation of the adherend after curing, thereby improving the flexibility of the adhesive and reducing the risk of cracking under stress such as bending or stretching. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 The present invention is a flow chart for preparing a flexible UV-curable high temperature resistant adhesive; Figure 2 This is an electron microscope scanning image of the flexible UV-curable high temperature resistant adhesive prepared in Example 3.

[0032] Figure 3 Schematic diagram of the synthetic route of the main agent. DETAILED DESCRIPTION

[0033] The following embodiments are only used to more clearly illustrate the technical solutions of the present invention, and are not intended to limit the protection scope of the present invention.

[0034] The main compounds used in the examples and comparative examples are all commercially available products without any further purification.

[0035] Example 1

[0036] like Figure 1 As shown, a flexible UV curing high temperature resistant adhesive, the preparation method of which comprises the following steps: Step S1, weighing 10 g of polycaprolactone and 11 g of maleic anhydride, adding them to 40 g of toluene to dissolve, adding 0.3 g of p-toluenesulfonic acid, reacting at 100° C. for 8 h to obtain a crude active macromolecular monomer, distilling under reduced pressure at 80° C. for 30 min, and drying at 60° C. for 12 h to obtain an active macromolecular monomer.

[0037] Step S2: 2 g of active macromolecular monomer and 10 g of ethyl acrylate were added to 40 g of dichloromethane to dissolve, 0.5 g of azobisisobutyronitrile was added, and the mixture was reacted at 60° C. for 8 h to obtain a block copolymer.

[0038] Step S3, weigh 10 g of glycidol and 20 g of block copolymer, mix, add 0.5 g of hydrochloric acid, react at 50° C. for 8 h to obtain a main agent, such as Figure 3 shown.

[0039] Step S4, mixing 10 g of the main agent with 1 g of nano-calcium carbonate, adding 1 g of hydrogenated castor oil, 0.5 g of N-nitroso-N-phenylhydroxylamine aluminum, 0.5 g of 2, 2'-methylenebis(4-methyl-6-tert-butylphenol), 0.2 g of sodium alkylbenzene sulfonate, and 0.5 g of 2-hydroxy-2-methyl-1-phenylacetone, and stirring at 30°C for 3 h to obtain a flexible UV-curable high temperature resistant adhesive.

[0040] Example 2

[0041] like Figure 1 As shown, a flexible UV curing high temperature resistant adhesive, the preparation method of which comprises the following steps: Step S1, weighing 10 g of polycaprolactone and 13 g of maleic anhydride, adding them to 45 g of toluene to dissolve, adding 0.4 g of methanesulfonic acid, reacting at 120° C. for 7 h to obtain a crude active macromolecular monomer, distilling under reduced pressure at 90° C. for 20 min, and drying at 70° C. for 10 h to obtain an active macromolecular monomer.

[0042] Step S2: 3 g of active macromolecular monomer and 10 g of ethyl acrylate were added to 45 g of dichloromethane to dissolve, 0.75 g of ammonium persulfate was added, and the mixture was reacted at 75° C. for 6 h to obtain a block copolymer.

[0043] Step S3, weigh 10 g of glycidol and 35 g of block copolymer, add 1 g of sulfuric acid, and react at 70° C. for 6 h to obtain a main agent, such as Figure 3 shown.

[0044] Step S4, mix 10 g of the main agent with 1.5 g of nano-calcium carbonate, add 2 g of hydrogenated castor oil, 0.75 g of 2,4-dimethyl-6-tert-butylphenol, 0.75 g of tris(2,4-di-tert-butylphenyl)phosphite, 0.3 g of fatty alcohol polyoxyethylene ether, and 0.75 g of benzoin dimethyl ether, and stir at 50° C. for 2 h to obtain a flexible UV-curable high-temperature resistant adhesive.

[0045] Example 3

[0046] like Figure 1 As shown, a flexible UV curing high temperature resistant adhesive, the preparation method of which comprises the following steps: Step S1, weighing 10 g of polycaprolactone and 15 g of maleic anhydride, adding them into 50 g of toluene to dissolve, adding 0.5 g of N,N'-dimethylaminopyridine, reacting at 150°C for 5 h to obtain a crude active macromolecular monomer, distilling under reduced pressure at 90°C for 10 min, and drying at 70°C for 10 h to obtain an active macromolecular monomer.

[0047] Step S2: 4 g of active macromolecular monomer and 10 g of ethyl acrylate were added to 50 g of dichloromethane to dissolve, 1 g of tert-butyl perbenzoate was added, and the mixture was reacted at 90° C. for 4 h to obtain a block copolymer.

[0048] Step S3, weigh 10 g of glycidol and 35 g of block copolymer, add 1 g of sulfuric acid, and react at 70° C. for 6 h to obtain a main agent, such as Figure 3 shown.

[0049] Step S4: 10 g of the main agent was mixed with 1.5 g of nano-calcium carbonate, 3 g of hydrogenated castor oil, 1 g of p-hydroxyanisole, 1 g of 2,6-di-tert-butyl-4-methylphenol, 0.5 g of cocamidopropyl betaine, and 1 g of 1-hydroxycyclohexyl phenyl ketone were added, and the mixture was stirred at 60° C. for 1 h to obtain a flexible UV-curable high temperature resistant adhesive. Figure 2 This is an electron microscope scanning image of the flexible UV-curing high-temperature resistant adhesive.

[0050] Comparative Example 1 A flexible UV-curable high temperature resistant adhesive, which is different from Example 3 in terms of preparation method in that polycaprolactone is not introduced into the main agent.

[0051] Comparative Example 2 A flexible UV-curable high temperature resistant adhesive, which is different from Example 3 in terms of preparation method in that glycidol is not introduced into the main agent.

[0052] Comparative Example 3 A flexible UV-curable high temperature resistant adhesive, which differs from Example 3 in terms of preparation method in that nano calcium carbonate is not added in step S4.

[0053] Comparative Example 4 A flexible UV-curable high temperature resistant adhesive, which is different from Example 3 in terms of preparation method in that hydrogenated castor oil is not added in step S4.

[0054] Performance Test: (1) Curing speed: Apply the flexible UV-curable high-temperature resistant adhesive on the substrate, use a light curing instrument, set the UV light intensity to 100 mW / cm² and the wavelength to 365 nm, start irradiation, and use a stopwatch to record the time from the start of irradiation to the complete curing of the flexible UV-curable high-temperature resistant adhesive.

[0055] (2) 180° peel strength: measured according to the method specified in GB / T 2790-1995.

[0056] (3) Shear strength: measured according to the method specified in GB / T 7124-2008.

[0057] (4) High temperature resistance: The samples bonded with the flexible UV-curable high temperature resistant adhesives prepared in Examples 1 to 3 and Comparative Examples 1 to 4 were placed in a high temperature box and heated to a set temperature of 180°C at a rate of 5°C / min. The temperature was maintained for 4 h. The samples were taken out and cooled to room temperature. The appearance of the flexible UV-curable high temperature resistant adhesive was observed for discoloration, bubbling, cracking, etc., and the 180° peel strength and shear strength were tested.

[0058] (5) Water resistance: The samples bonded with the flexible UV-curable high temperature resistant adhesives prepared in Examples 1 to 3 and Comparative Examples 1 to 4 were immersed in water at room temperature (25°C) and 60°C for 10 days to observe whether the flexible UV-curable high temperature resistant adhesives showed whitening, swelling, or shedding, and their 180° peel strength and shear strength were tested.

[0059] (6) Flexibility: The substrate coated with the flexible UV-curing high-temperature resistant adhesive was made into a 10×15 cm specimen and bent on a bending tester with a bending radius of 5 mm, 10 mm, and 15 mm and a bending speed of 10 mm / min. The flexible UV-curing high-temperature resistant adhesive was observed to see if cracks or peeling occurred, and the number of bends or the bending radius when damage occurred was recorded.

[0060] The performance test results of the flexible UV-curable high temperature resistant adhesives prepared in Examples 1 to 3 and Comparative Examples 1 to 4 are shown in Tables 1 to 5.

[0061] Table 1 Curing speed test data

[0062] According to the data in Table 1, the curing speeds of the flexible UV-curable high-temperature-resistant adhesives prepared in Examples 1 to 3 and Comparative Examples 1 to 4 under UV light are similar, and the flexible UV-curable high-temperature-resistant adhesives prepared in Examples 1 to 3 cure faster. The experiment proves that the flexible UV-curable high-temperature-resistant adhesive obtained by the preparation method of the flexible UV-curable high-temperature-resistant adhesive of the present invention can be quickly cured under UV light.

[0063] Table 2 Peel strength and shear strength test data

[0064] According to the data in Table 2, the 180° peel strength of the flexible UV-curable high-temperature resistant adhesives prepared in Examples 1 to 3 is higher than 30 N / mm, followed by Comparative Examples 3 and 4, with a 180° peel strength of 28 N / mm; while the peel strength of Comparative Example 1 is only 16 N / mm, significantly lower than that of the other groups. The shear strength of the flexible UV-curable high-temperature resistant adhesives prepared in Examples 1 to 3 and Comparative Examples 3 and 4 is also better than that of the flexible UV-curable high-temperature resistant adhesives prepared in Comparative Examples 1 and 2. Experiments have shown that the flexible UV-curable high-temperature resistant adhesive obtained by ring-opening polymerization of glycidol and a modified acrylic precursor and the introduction of polycaprolactone has good anti-destruction ability and bonding performance. Comparative Example 1 lacks polycaprolactone, and Comparative Example 2 lacks glycidol, so a stable three-dimensional network structure cannot be constructed, weakening its ability to resist external damage.

[0065] Table 3 High temperature resistance test data

[0066] According to the data in Table 3, the flexible UV-curable high-temperature-resistant adhesives prepared in Examples 1 to 3 and Comparative Examples 3 and 4 did not change in appearance after being placed at 180°C for 4 hours, and the peel strength and shear strength were not significantly different from those of the normal group (Table 2). However, the flexible UV-curable high-temperature-resistant adhesives prepared in Comparative Examples 1 and 2 showed discoloration and debonding in the adhesive layer after 4 hours. Experiments have shown that the structure of the flexible UV-curable high-temperature-resistant adhesives prepared in Comparative Examples 1 and 2 is easily destroyed in a continuous high-temperature environment, resulting in a weakened adhesive bonding effect.

[0067] Table 4 Water resistance test data

[0068] According to the data in Table 4, the flexible UV-curable high temperature resistant adhesives prepared in Examples 1 to 3 and Comparative Example 4 did not show any changes such as swelling or falling off after being placed in water at 25°C and 60°C for 10 days, while the flexible UV-curable high temperature resistant adhesives prepared in Comparative Example 1 and Comparative Example 2 both showed falling off after being placed in water at 25°C and 60°C for 10 days; the flexible UV-curable high temperature resistant adhesive prepared in Comparative Example 3 swelled after being soaked at 25°C for 10 days, and the adhesive layer fell off after being soaked at 60°C for 10 days; the experiment showed that the structures of the flexible UV-curable high temperature resistant adhesives prepared in Comparative Examples 1 and 2 could not stably exist in water, and the structure of Comparative Example 3 was more stable than that of Comparative Examples 1 and 2, but nano-calcium carbonate was not added, and its waterproofness was poorer than that of Examples 1 to 3 and Comparative Example 4.

[0069] Table 5 Flexibility test data

[0070] According to the data in Table 5, the flexible UV-curable high-temperature resistant adhesives prepared in Examples 1 to 3 can withstand more than 40,000 bendings at a curvature radius of 5, 10 and 15 mm and a bending speed of 10 mm / min, showing good flexibility; followed by the flexible UV-curable high-temperature resistant adhesives prepared in Comparative Examples 1 to 3. The smaller the curvature radius, the lower the maximum number of bending times it can withstand, and obvious cracking occurs; the flexible UV-curable high-temperature resistant adhesive prepared in Comparative Example 4 has the worst flexibility compared to Examples 1 to 3 and Comparative Examples 1 to 3. No hydrogenated castor oil is added in Comparative Example 4 because the hydrogenated castor oil molecular chain contains a large number of saturated fatty acid segments, which have good flexibility and can be integrated into the molecular network of the adhesive as a flexible segment, so that the adhesive can better adapt to the deformation of the adherend after curing, thereby improving the flexibility of the adhesive and reducing the risk of cracking under stress such as bending or stretching.

[0071] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A flexible UV curable high temperature resistant adhesive, characterized in that: The flexible UV curable high temperature resistant adhesive comprises a main agent, nano calcium carbonate, hydrogenated castor oil, an inhibitor, an antioxidant, a surfactant and a photoinitiator; the mass ratio of the main agent, nano calcium carbonate, hydrogenated castor oil, inhibitor, antioxidant, surfactant and photoinitiator is 1: (0.1-0.15): (0.1-0.3): (0.1-0.5): (0.1-0.5): (0.02-0.05): (0.05-0.1); the main agent structural formula is as follows: ， Wherein, in the main agent structural formula, n is an integer between 1 and 10, α is an integer between 1 and 10, and β is an integer between 1 and 10, and α and β can be the same value or different values.

2. The method for preparing a flexible UV curable high temperature resistant adhesive according to claim 1, characterized in that: include: Step S1, adding polycaprolactone and maleic anhydride into a first solvent to dissolve, adding a catalyst, reacting to obtain a crude active macromolecular monomer product, and subjecting the crude product to reduced pressure distillation and drying to obtain an active macromolecular monomer; Step S2, adding the active macromolecular monomer and the acrylic acid monomer into a second solvent to dissolve, adding an initiator, and reacting to obtain a block copolymer; Step S3, mixing glycidol and the block copolymer, adding a catalyst, and reacting to obtain a main agent; Step S4, mixing the main agent with nano calcium carbonate, adding hydrogenated castor oil, polymerization inhibitor, antioxidant, surfactant and photoinitiator, and stirring to obtain a flexible UV curable high temperature resistant adhesive.

3. The method for preparing a flexible UV curable high temperature resistant adhesive according to claim 2, characterized in that: In step S1, the first solvent is any one or more of toluene, acetonitrile, xylene, and N,N'-dimethylformamide; the catalyst is any one or more of p-toluenesulfonic acid, methanesulfonic acid, scandium trifluoromethanesulfonate, and N,N'-dimethylaminopyridine.

4. The method for preparing a flexible UV curable high temperature resistant adhesive according to claim 2, characterized in that: In the step S1, the mass ratio of the polycaprolactone, maleic anhydride, the first solvent and the catalyst is 1: (1.1-1.5): (4-5): (0.03-0.05); the reaction temperature is 100-150° C., and the reaction time is 5-8 h; the reduced pressure distillation temperature is 80-90° C., and the time is 10-30 min; the drying temperature is 60-70° C., and the drying time is 10-12 h.

5. The method for preparing a flexible UV curable high temperature resistant adhesive according to claim 2, characterized in that: In step S2, the second solvent is any one or more of dichloromethane, tetrahydrofuran, and toluene; the initiator is any one or more of azobisisobutyronitrile, ammonium persulfate, potassium persulfate, and tert-butyl perbenzoate; and the acrylic acid monomer is any one or more of ethyl acrylate, butyl acrylate, isooctyl acrylate, and lauryl acrylate.

6. The method for preparing a flexible UV curable high temperature resistant adhesive according to claim 2, characterized in that: In the step S2, the mass ratio of the active macromolecular monomer, the acrylic acid monomer, the second solvent and the initiator is 1: (0.2-0.4): (4-5): (0.05-0.1); the reaction temperature is 60-90° C., and the reaction time is 4-8 h.

7. The method for preparing a flexible UV curable high temperature resistant adhesive according to claim 2, characterized in that: In step S3, the catalyst is any one or more of sulfuric acid, hydrochloric acid, perchloric acid, and phosphoric acid; the mass ratio of glycidol, block copolymer, and catalyst is 1:(2-5):(0.05-0.2); the reaction temperature is 50-90° C., and the reaction time is 3-8 hours.

8. The method for preparing a flexible UV curable high temperature resistant adhesive according to claim 2, characterized in that: In the step S4, the inhibitor is any one or more of N-nitroso-N-phenylhydroxylamine aluminum, 2,4-dimethyl-6-tert-butylphenol, and p-hydroxyanisole; the antioxidant is any one or more of 2,2'-methylenebis(4-methyl-6-tert-butylphenol), tris(2,4-di-tert-butylphenyl)phosphite, and 2,6-di-tert-butyl-4-methylphenol.

9. The method for preparing a flexible UV curable high temperature resistant adhesive according to claim 2, characterized in that: In the step S4, the surfactant is any one or more of sodium alkylbenzene sulfonate, fatty alcohol polyoxyethylene ether, cocamidopropyl betaine, and hexadecyltrimethylammonium bromide; the photoinitiator is a free radical photoinitiator, including any one or more of 1-hydroxycyclohexyl phenyl ketone, benzoin dimethyl ether, 2-hydroxy-2-methyl-1-phenyl-1-propanone, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, and bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide; the stirring temperature is 30-60° C., and the stirring time is 1-3 h.

10. The flexible UV curing high temperature resistant adhesive according to claim 1 is used for bonding pebax, TPU and TPE elastic substrates.

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