An environmentally friendly insulating coating and its preparation method

Abstract

This invention discloses an environmentally friendly insulating coating and its preparation method, belonging to the field of environmentally friendly coatings. The invention is prepared by a two-step epoxy ring-opening reaction of hydroxyl-terminated polybutadiene with glycidyl (meth)acrylate and an epoxy compound containing a bridged ring structure, followed by a hydrolytic condensation reaction with a silane coupling agent. The resulting modified hydroxyl-terminated polybutadiene, together with alicyclic acrylate soft and hard monomers containing bridged ring structures, pigments, and leveling agents, is then reacted with a photoinitiator to produce an insulating coating. This insulating coating exhibits excellent insulation properties, mechanical strength, heat resistance, and aging resistance, and can be applied to the outer insulating layer of new energy batteries, replacing the existing blue film adhesive process.

Description

Technical Field

[0001] This invention relates to an environmentally friendly insulating coating and its preparation method, belonging to the field of environmentally friendly coatings. Background Technology

[0002] The battery cell is the smallest unit that makes up the battery system. Its aluminum outer shell is covered with a blue single-sided release protective film, which is a high-molecular polyester (PET) material. However, the PET blue film has problems such as low adhesion rate, low adhesion between pressure-sensitive adhesive and battery cell and PET, which leads to bubbling, slippage and falling off. After long-term use, the battery has the risk of flammability and short circuit.

[0003] With the rapid development of the new energy vehicle market, especially the emergence of new models based on 800V high-voltage platforms, traditional insulation solutions are facing severe challenges. Compared to traditional blue film processes, UV coating can achieve fully automated production lines, efficiently completing the spraying and curing of products on all six sides without the need for additional baking equipment. This simplifies the production process, reduces labor costs, improves overall coating efficiency, and generates no solvents, making it more environmentally friendly.

[0004] CN119708994A discloses an insulating coating for UV-based batteries, comprising a specially modified polyurethane acrylate, isoborneol methacrylate, epoxy acrylate, dispersant, dual initiator components, additives, etc., which are cured by synergistic curing with two photoinitiators to obtain an insulating coating with excellent adhesion, anti-aging properties, adhesion, insulation resistance, and impact resistance.

[0005] Patent US20230002636A1 discloses an ultraviolet insulating coating for insulating battery cells and battery packs, comprising one or more acrylate monomers, polyurethane prepolymers, crosslinking agents, thickeners, photoinitiators, and fillers or additives, which can achieve rapid coating and curing and has high adhesion strength. However, the porous structure of the fumed silica added in this solution leads to a decrease in electrolyte resistance.

[0006] Currently, insulating coatings mainly use systems such as acrylate, polyurethane, and silicone. Acrylic and polyurethane systems are not ideal in terms of electrical properties and resistance to high and low temperature impacts, while silicone systems have shortcomings in terms of insulation, flame retardancy, and antistatic dust adhesion.

[0007] To improve the safety of new energy batteries, developing insulating materials for power batteries with excellent insulation properties, mechanical strength, adhesion, resistance to high and low temperature impacts, and aging resistance remains an urgent problem to be solved. Summary of the Invention

[0008] To address the aforementioned problems, this invention provides an environmentally friendly insulating coating and its preparation method. The photocurable insulating coating comprises a modified hydroxyl-terminated polybutadiene oligomer, an reactive diluent, a photoinitiator, a pigment, and a leveling agent. The modified hydroxyl-terminated polybutadiene oligomer used in this invention is prepared by reacting hydroxyl-terminated polybutadiene with glycidyl (meth)acrylate and an epoxy compound containing a bridged ring structure through a two-step ring-opening reaction and a hydrolytic condensation reaction with a silane coupling agent.

[0009] Beneficial effects This invention synthesizes modified hydroxyl-terminated polybutadiene with a specific structure through molecular design, and selects alicyclic acrylates with bridged ring structures as soft and hard monomers as reactive diluents. Through structural design and experimental route design, an environmentally friendly insulating coating is prepared, which has high hardness and toughness, reducing the possibility of damage caused by collisions and scratches; it also has good insulation properties, providing better insulation and protection for the battery cell; the UV curing process greatly improves construction efficiency, and it is free of harmful solvents, making it environmentally friendly.

[0010] The first objective of this invention is to provide a modified hydroxyl-terminated polybutadiene, the structural formula of which is shown in Formula I: ; In the formula, R1 is hydrogen or methyl, R2 is hydrogen or methyl, R3 is hydrogen or methyl, and k is 0, 1, or 2.

[0011] In one embodiment, the method for preparing the modified hydroxyl-terminated polybutadiene includes the following steps: (1) Add hydroxyl-terminated polybutadiene, solvent, catalyst and polymerization inhibitor to the reactor respectively, maintain a nitrogen atmosphere in the reactor, stir and maintain the temperature at 60~100℃, add glycidyl methacrylate to the dropping tank, drop for 1~3 h, maintain the reaction system temperature at 40~60℃ for reaction, and continue the reaction for 1~3 h to obtain intermediate product 1; (2) Add catalyst and polymerization inhibitor to intermediate product 1, and continue to add solvent and a mixture of epoxy compound containing bridged ring structure dropwise for 1-3 h, maintain reaction temperature at 80-110℃, react for 2-5 h, cool, and obtain intermediate product 2; (3) Adjust the pH of intermediate product 2 to 3.0~4.5 with acetic acid / sodium acetate buffer solution, then add silane coupling agent, stir at 25~45℃ for 1~5 h, then heat to 100~110℃, maintain for 1~5 h, and cool to obtain intermediate product 3; (4) After washing, drying, filtering and rotary evaporating intermediate product 3, modified hydroxyl-terminated polybutadiene is obtained.

[0012] In one embodiment, the hydroxyl-terminated polybutadiene has the structural formula shown in Formula II:

[0013] Among them, (a+c) / (a+b+c)=0.75~0.85, b / (a+b+c)=0.15~0.25, and the hydroxyl value is 0.8~2.0 mmol / g; Optionally, the solvent is one of toluene, xylene, N,N-dimethylformamide, and cyclohexanone; the amount of solvent added is 1 to 2 times the mass of the hydroxyl-terminated polybutadiene. Optionally, the catalyst is a boron trifluoride tetrahydrofuran solution or a boron trifluoride diethyl ether solution; the amount of catalyst added is 0.2% to 2.0% of the mass of the hydroxyl-terminated polybutadiene. Optionally, the polymerization inhibitor is one of p-methoxyphenol, 2,6-di-tert-butyl-p-cresol, or hydroquinone; the amount of polymerization inhibitor added is 0.1-0.5% of the mass of the hydroxyl-terminated polybutadiene. Optionally, the silane coupling agent is a methacryloyloxyalkylsilane with the structure shown in formulas X1 to X3: ; Where R' is , or , R'' is R''' is ; Optionally, the epoxide containing the bridged ring structure has the structure shown in Formula III:

[0014] Where k = 0, 1, or 2; R2 and R3 are H or CH3; Optionally, the amount of solvent added in step (2) is 20-50% of the mass of solvent added in step (1); the amount of catalyst added in step (2) is 20-50% of the mass of catalyst added in step (1); and the amount of polymerization inhibitor added in step (2) is 10-20% of the mass of polymerization inhibitor added in step (1).

[0015] In one embodiment, the amounts of hydroxyl-terminated polybutadiene, glycidyl (meth)acrylate, bridged ring-structured epoxy compound, and silane coupling agent involved in steps (1), (2), and (3) are as follows: n (molar amount of hydroxyl-terminated polybutadiene): n (molar amount of glycidyl methacrylate): n (molar amount of epoxy compound with bridged ring structure): n (molar amount of silane coupling agent) = (1.005~1.05): 1:1: (0.05~0.10).

[0016] In one embodiment, the modified hydroxyl-terminated polybutadiene is prepared by a two-step epoxy ring-opening reaction of hydroxyl-terminated polybutadiene with glycidyl methacrylate and an epoxy compound containing a bridged ring structure, followed by a hydrolytic condensation reaction with a silane coupling agent. The resulting modified hydroxyl-terminated polybutadiene contains polybutadiene chain units with flexible, fatigue-resistant rubber segments, making the protective coating less prone to cracking under thermal cycling or vibration. The double bonds of glycidyl methacrylate introduced by the glycidyl methacrylate make the intermediate a host resin capable of participating in free radical photopolymerization, enabling solvent-free rapid curing and online coating, reducing solvent residue. The epoxide containing the bridged ring structure endows the hydroxyl-terminated polybutadiene with excellent properties such as wear resistance and temperature resistance. The silane coupling agent used is methacryloyloxyalkylsilane. Its siloxane segments provide heat resistance, weather resistance, hydrophobicity, and resistance to moisture-induced electrical degradation. At the same time, it can improve the smoothness and anti-fouling properties of the coating surface, reduce the risk of assembly friction damage, and its "reactive" methacryloyloxy group can participate in the reaction. Unlike non-reactive silicone oil, it can migrate and contaminate the interface, making it more friendly to adhesion and long-term reliability. The hydrolyzable ethoxy or methoxy groups can undergo hydrolysis and condensation reactions with the hydroxyl groups in the terminal hydroxyl-modified oligomers to further form a cross-linked network and have good adhesion to the substrate.

[0017] In one embodiment, the modified hydroxyl-terminated polybutadiene is prepared by a two-step epoxy ring-opening reaction of (meth)acrylate and an epoxy compound with a bridged ring structure, followed by hydrolysis and condensation modification with a silane coupling agent.

[0018] In one embodiment, the alicyclic acrylate monomer with a bridged ring structure / alicyclic ethoxy acrylate monomer with a bridged ring structure is often used to improve Tg, hardness, scratch resistance, and solvent resistance. At the same time, it helps to reduce polymerization shrinkage and curing internal stress. The "ethoxy" diluent further improves the wetting and leveling properties, making it easier for the coating to cover complex corners, around tabs and local gaps, and reducing the probability of pinholes.

[0019] In one embodiment, the washing in step (4) consists of washing once with a 0.5-2.0% sodium hydroxide aqueous solution, washing twice with saturated saline solution, and washing 1-3 times with deionized water.

[0020] In one embodiment, the volume of the 0.5-2.0% sodium hydroxide aqueous solution used in step (4) is 1-3 times the volume of intermediate product 3.

[0021] In one embodiment, the volume of saturated brine used in step (4) is 1 to 3 times the volume of intermediate product 3 in step (3).

[0022] In one embodiment, the volume of deionized water used in step (4) is 1 to 3 times the volume of intermediate product 3 in step (3).

[0023] The second objective of this invention is to provide a method for preparing an environmentally friendly insulating coating, which is prepared using the modified hydroxyl-terminated polybutadiene described above, and includes the following steps: Add modified hydroxyl-terminated polybutadiene and reactive diluent to the mixer, control the stirring speed at 1000~1200 rpm, and stir for 5~10 min until uniformly dispersed; then, while maintaining the stirring speed at 1000~1200 rpm, continue to add photoinitiator and leveling agent, and stir for 5~15 min; then adjust the stirring speed to 1200~1500 rpm, continue to add pigment, and stir for 15~30 min to form a premix; The premixed material is ground to a particle size of less than 15 μm and filtered through a 150-250 mesh filter to obtain an environmentally friendly insulating coating.

[0024] In one embodiment, the mass ratio of modified hydroxyl-terminated polybutadiene: reactive diluent: photoinitiator: pigment: leveling agent is 55~70: 25~40: 2~5: 0.5~2: 0.1~0.5.

[0025] In one embodiment, the reactive diluent is two alicyclic acrylate monomers, La and Lb, containing a bridged ring structure, wherein the mass ratio of La to Lb is 0.5~0.8:0.2~0.5; La structure (Formula IV): , R4 and R5 are H or CH3, k = 0, 1 or 2; Lb structure (Form V): , R6 and R7 are H or CH3, and k = 0, 1 or 2.

[0026] In one embodiment, the reactive diluent La is a hard acrylate monomer and Lb is a soft acrylate monomer.

[0027] In one embodiment, the photoinitiator includes one or more of the following: 2-hydroxy-2-methylphenylacetone (photoinitiator 1173), 1-hydroxycyclohexylphenyl ketone (photoinitiator 184), α,α-dimethoxy-α-phenylacetophenone (photoinitiator 651), diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (photoinitiator TPO), phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide (photoinitiator 819), 2-isopropylthioxanthone (photoinitiator ITX), ethyl 4-dimethylaminobenzoate (photoinitiator EDB), 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone (photoinitiator 910), 2,2-dimethoxy-2-phenylacetophenone (photoinitiator 651), and 2-methyl-1-(4-methylthiophenyl)-2-morpholino-1-propanone (photoinitiator 907). Optionally, the leveling agent is a polyether siloxane copolymer, commercially available brands such as TEGO Glide 410, TEGO Glide 450, HY-100, and BYK379. Optionally, the pigment is a UV blue pigment, commercially available under the designations US058, US237, and UV15:4 Blue-20.

[0028] A third objective of this invention is to provide an environmentally friendly insulating coating prepared by any of the methods described above.

[0029] In one embodiment, the environmentally friendly insulating coating is an insulating coating cured by a UV curing process, with curing conditions of UVA light intensity of 1500~1900mW / cm². 2 The light dose is 2000~2500 mJ / cm. 2 The curing time is 5~60 seconds.

[0030] The fourth objective of this invention is to provide the application of the modified hydroxyl-terminated polybutadiene or the environmentally friendly insulating coating described above in the outer insulating layer of new energy batteries. Attached Figure Description

[0031] Figure 1 This is a synthetic route diagram for modified hydroxyl-terminated polybutadiene. Detailed Implementation

[0032] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. These embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Experimental methods in the following embodiments, where specific conditions are not specified, are generally performed under conventional conditions in the art. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those familiar with the art.

[0033] The synthetic route diagram of modified hydroxyl-terminated polybutadiene is as follows: Figure 1As shown.

[0034] Raw material source: Hydroxyl-terminated polybutadiene ((a+c) / (a+b+c)=0.75, b / (a+b+c)=0.25, hydroxyl value 0.8 mmol / g), hydroxyl-terminated polybutadiene ((a+c) / (a+b+c)=0.80, b / (a+b+c)=0.20, hydroxyl value 1.0 mmol / g), and hydroxyl-terminated polybutadiene ((a+c) / (a+b+c)=0.85, b / (a+b+c)=0.15, hydroxyl value 2.0 mmol / g), purchased from Sartoma Chemical Co., Ltd., have the following structural formulas: ; (Meth)acrylate glycidyl ester was purchased from Sigma-Aldrich (Shanghai) Trading Co., Ltd. Toluene, boron trifluoride ether solution, p-methoxyphenol, 2,6-di-tert-butyl-p-cresol, N,N-dimethylformamide, xylene, hydroquinone, and cyclohexanone were purchased from Sinopharm Chemical Reagent Co., Ltd. Photoinitiator 1173, photoinitiator 184, photoinitiator 651, photoinitiator TPO, photoinitiator 819, photoinitiator 910, photoinitiator 907, and photoinitiator EDB were purchased from Sigma-Aldrich (Shanghai) Trading Co., Ltd. Pigment (US058) and pigment (US237) were purchased from Shanghai WaiDian International Trade Co., Ltd., and pigment (UV15:4 Blue-20) was purchased from Shanghai Ruifu Chemical Co., Ltd. Leveling agents (TEGO Glide 410) and (TEGO Glide 450) were purchased from Evonik Specialty Chemicals (Shanghai) Co., Ltd., leveling agent (HY-100) was purchased from Shanghai Huiyan New Materials Co., Ltd., and leveling agent (BYK379) was purchased from BYK Additives (Shanghai) Co., Ltd. CAS No. 2530-85-0, purchased from Bailingwei Technology Group. CAS No. 21142-29-0, purchased from Bailingwei Technology Group. CAS No. 17096-07-0, purchased from Bailingwei Technology Group. CAS No. 13731-98-1, purchased from Bailingwei Technology Group. CAS No. 57069-48-4, purchased from Bailingwei Technology Group.

[0035] Epoxy compounds containing bridged ring structures ( The preparation method of cyclic olefin compounds (k=0, 1 or 2, R2 and R3 are H or CH3) is as follows: It is prepared by epoxidation reaction with peracetic acid, as described in patent CN201711339235.3.

[0036] The reactive diluent was purchased from Wuxi Akoli Technology Co., Ltd. or prepared using the following method: Reactive diluent La ( The preparation method of ) is as follows: Cycloolefins and acrylic acid can be reacted via an acid-olefin addition reaction under the action of an acid catalyst to obtain the active diluent La. Referring to patents US3087962 and JP-58049337, the reaction formula is:

[0037] In the formula, R4 and R5 are H or CH3, and k = 0, 1 or 2; Reactive diluent Lb ( The preparation method of ) is as follows: ethylene glycol ether containing a bridged ring structure is prepared by etherification reaction of cyclic olefins and ethylene glycol under the action of a catalyst. The ethylene glycol ether containing the bridged ring structure is then esterified with acrylic acid to obtain the active diluent Lb. Referring to patent CN1600767A and literature (Jiang Shuojian, Li Mingqian, Wan Quan. Deodorization study of (meth)acrylate dicyclopentenyl ester [J]. China Coatings, 1999, (5):37-38.), the reaction formula is:

[0038] In the formula, R6 and R7 are H or CH3, and k = 0, 1 or 2.

[0039] The measurement methods involved in the examples are as follows: Dielectric strength: The dielectric constant tester was used with a ZJD-B fully digital display instrument, in accordance with GB / T 1409-2006.

[0040] Insulation resistance: Tested according to GB / T 31838.4-2019, with a DC 2000V load for 60 seconds.

[0041] Withstand voltage and leakage current: According to GB / T 1408.1-2016, 5000 V, 60 s.

[0042] Shear strength: Tested according to GB / T 7124-2008, with a test temperature of 25℃, a tensile speed of 5mm / min, and a coating thickness of 0.2mm.

[0043] Hardness: Tested according to GB / T 6739-2006, load 750 g.

[0044] Adhesion test: conducted in accordance with GB / T 9286-2021.

[0045] Impact resistance: Tested according to GB / T 1732-2020, impact load 1 Kg.

[0046] Wear resistance: Tested according to GB / T 1768-2006, with a load of 1 kg and friction medium CS-17, for 1000 cycles.

[0047] High and low temperature shock: According to GB / T 2423.22-2012, the sample is placed in an alternating temperature environment of -40℃ to 85℃, the transition time between the two extreme temperatures is within 3 minutes, one cycle is 2 hours, 500 cycles are performed, and a total of 1000 hours are performed.

[0048] Aging test: conducted according to GB / T 2423.2-2016, 85℃, 85%RH, 1000 h.

[0049] Example 1: Preparation of modified hydroxyl-terminated polybutadiene The preparation steps of modified hydroxyl-terminated polybutadiene are as follows: (1) 250 g of hydroxyl-terminated polybutadiene ((a+c) / (a+b+c)=0.75, b / (a+b+c)=0.25, hydroxyl value 0.8 mmol / g), 250 g of toluene, 2.5 g of boron trifluoride tetrahydrofuran solution, and 0.25 g of p-methoxyphenol were added to the reactor respectively. The reactor was kept under a nitrogen atmosphere, stirred and kept at 60°C. 28.3 g of glycidyl methacrylate was added to the dropping tank and the dropping time was 1 h. The reaction system was kept at 60°C and the reaction was continued for 1 h to obtain intermediate product 1.

[0050] (2) Add 0.2 g of boron trifluoride tetrahydrofuran solution and 0.02 g of p-methoxyphenol to intermediate product 1, and continue to add 50 g of toluene and 21.9 g of an epoxy compound containing a bridged ring structure. A mixture of (k=0) was added dropwise over 1 hour, and the reaction temperature was maintained at 80°C for 2 hours. After cooling, intermediate product 2 was obtained.

[0051] (3) Adjust the pH of intermediate 2 to 3.0 with acetic acid / sodium acetate buffer solution, and then add 2.5 g of methacryloyloxysilane ( Stir at 25°C for 2 h, then raise the temperature to 100°C, hold for 1 h, and then cool to obtain intermediate product 3.

[0052] (4) The intermediate product 3 was washed once with 700 mL of 0.5% sodium hydroxide aqueous solution, twice with 700 mL of saturated saline solution, and three times with 700 mL of deionized water. It was then dried with anhydrous magnesium sulfate, filtered, and the solvent was removed by rotary evaporation to obtain modified hydroxyl-terminated polybutadiene A.

[0053] Example 2: Preparation of modified hydroxyl-terminated polybutadiene The preparation steps of modified hydroxyl-terminated polybutadiene are as follows: (1) 250 g of hydroxyl-terminated polybutadiene ((a+c) / (a+b+c)=0.80, b / (a+b+c)=0.20, hydroxyl value 1.0 mmol / g), 500 g of toluene, 1.25 g of boron trifluoride ether solution, and 0.50 g of p-methoxyphenol were added to the reactor. The reactor was kept under a nitrogen atmosphere, stirred and kept at 60°C. 33.8 g of glycidyl methacrylate was added to the dropping tank and dropped for 1.5 h. The reaction system was kept at 40°C and the reaction was continued for 3 h to obtain intermediate product 1.

[0054] (2) Add 0.625 g of boron trifluoride diethyl ether solution and 0.1 g of p-methoxyphenol to intermediate product 1, and continue to add 100 g of toluene and 29.6 g of an epoxy compound containing a bridged ring structure. A mixture of (k=0, R2 is CH3) was added dropwise for 3 h, the reaction temperature was maintained at 100℃, the reaction was carried out for 2 h, and then cooled to obtain intermediate product 2.

[0055] (3) Adjust the pH of intermediate 2 to 3.0 with acetic acid / sodium acetate buffer solution, and then add 5.9 g of methacryloyloxysilane ( Stir at 35°C for 1 h, then raise the temperature to 110°C, maintain for 5 h, and then cool to obtain intermediate product 3.

[0056] (4) The intermediate product 3 was washed once with 1500 mL of 1.0% sodium hydroxide aqueous solution, twice with 1500 mL of saturated saline solution, and three times with 1500 mL of deionized water. It was then dried with anhydrous magnesium sulfate, filtered, and the solvent was removed by rotary evaporation to obtain modified hydroxyl-terminated polybutadiene B.

[0057] Example 3: Preparation of modified hydroxyl-terminated polybutadiene The preparation steps of modified hydroxyl-terminated polybutadiene are as follows: (1) 250 g of hydroxyl-terminated polybutadiene ((a+c) / (a+b+c)=0.85, b / (a+b+c)=0.15, hydroxyl value 2.0 mmol / g), 250 g of xylene, 7.5 g of boron trifluoride tetrahydrofuran solution, and 0.05 g of p-methoxyphenol were added to the reactor respectively. The reactor was kept under a nitrogen atmosphere, stirred and kept at 80°C. 71.1 g of glycidyl methacrylate was added to the dropping tank and the dropping time was 2 h. The reaction system temperature was kept at 60°C and the reaction was continued for 3 h to obtain intermediate product 1.

[0058] (2) Add 1.2 g of boron trifluoride tetrahydrofuran solution and 0.01 g of p-methoxyphenol to intermediate product 1, and continue to add 125 g of xylene and 69.1 g of epoxide compound containing a bridged ring structure. A mixture of (k=0, R2 and R3 are CH3) was added dropwise for 1 hour, the reaction temperature was maintained at 80℃, the reaction was carried out for 5 hours, and then cooled to obtain intermediate product 2.

[0059] (3) Adjust the pH of intermediate 2 to 3.0 with acetic acid / sodium acetate buffer solution, and then add 14.5 g of methacryloyloxysilane ( Stir at 25°C for 5 h, then raise the temperature to 110°C, hold for 1 h, and then cool to obtain intermediate product 3.

[0060] (4) The intermediate product 3 was washed once with 2500 mL of 0.5% sodium hydroxide aqueous solution, twice with 2500 mL of saturated saline solution, and twice with 2500 mL of deionized water. It was then dried with anhydrous magnesium sulfate, filtered, and the solvent was removed by rotary evaporation to obtain modified hydroxyl-terminated polybutadiene C.

[0061] Example 4: Preparation of modified hydroxyl-terminated polybutadiene The preparation steps of modified hydroxyl-terminated polybutadiene are as follows: (1) 250 g of hydroxyl-terminated polybutadiene ((a+c) / (a+b+c)=0.75, b / (a+b+c)=0.25, hydroxyl value 0.8 mmol / g), 300 g of xylene, 1.25 g of boron trifluoride tetrahydrofuran solution, and 0.25 g of 2,6-di-tert-butyl-p-cresol were added to the reactor. The reactor was kept under a nitrogen atmosphere. The mixture was stirred and kept at a temperature of 60°C. 28.3 g of glycidyl methacrylate was added to the dropping tank. The dropping time was 1 h. The reaction system was kept at a temperature of 60°C and the reaction was continued for 3 h to obtain intermediate product 1.

[0062] (2) Add 0.25 g of boron trifluoride tetrahydrofuran solution and 0.05 g of 2,6-di-tert-butyl-p-cresol to intermediate product 1, and continue to add 100 g of xylene and 35.0 g of an epoxy compound containing a bridged ring structure. A mixture of (k=1) was added dropwise over 2 hours, the reaction temperature was maintained at 80°C, and the reaction was carried out for 2 hours. After cooling, intermediate product 2 was obtained.

[0063] (3) Adjust the pH of intermediate 2 to 4.0 with acetic acid / sodium acetate buffer solution, and then add 4.6 g of methacryloyloxysilane ( Stir at 25°C for 5 h, then raise the temperature to 100°C, hold for 2 h, and then cool to obtain intermediate product 3.

[0064] (4) The intermediate product 3 was washed once with 1600 mL of 0.5% sodium hydroxide aqueous solution, twice with 1600 mL of saturated saline solution, and once with 1600 mL of deionized water. It was then dried with anhydrous magnesium sulfate, filtered, and the solvent was removed by rotary evaporation to obtain modified hydroxyl-terminated polybutadiene D.

[0065] Example 5: Preparation of modified hydroxyl-terminated polybutadiene The preparation steps of modified hydroxyl-terminated polybutadiene are as follows: (1) 250 g of hydroxyl-terminated polybutadiene ((a+c) / (a+b+c)=0.80, b / (a+b+c)=0.20, hydroxyl value 1.0 mmol / g), 250 g of N,N-dimethylformamide, 5 g of boron trifluoride tetrahydrofuran solution, and 0.5 g of 2,6-di-tert-butyl-p-cresol were added to the reactor. The reactor was kept under a nitrogen atmosphere. The mixture was stirred and kept at 80°C. 30.5 g of glycidyl acrylate was added to the dropping tank. The dropping time was 1 h. The reaction system temperature was kept at 60°C and the reaction was continued for 1 h to obtain intermediate product 1.

[0066] (2) Add 1.0 g of boron trifluoride tetrahydrofuran solution and 0.1 g of 2,6-di-tert-butyl-p-cresol to intermediate product 1, and continue to add 50 g of N,N-dimethylformamide and 45.3 g of an epoxy compound containing a bridged ring structure. A mixture of (k=1, R2 is CH3) was added dropwise over 2 h, the reaction temperature was maintained at 80℃, the reaction was carried out for 2 h, and then cooled to obtain intermediate product 2.

[0067] (3) Adjust the pH of intermediate 2 to 4.0 with acetic acid / sodium acetate buffer solution, and then add 10.1 g of methacryloyloxysilane ( Stir at 30°C for 1 h, then raise the temperature to 110°C, maintain for 5 h, and then cool to obtain intermediate product 3.

[0068] (4) The intermediate product 3 was washed once with 1000 mL of 0.5% sodium hydroxide aqueous solution, twice with 1600 mL of saturated saline solution, and three times with 1600 mL of deionized water. It was then dried with anhydrous magnesium sulfate, filtered, and the solvent was removed by rotary evaporation to obtain modified hydroxyl-terminated polybutadiene E.

[0069] Example 6: Preparation of modified hydroxyl-terminated polybutadiene The preparation steps of modified hydroxyl-terminated polybutadiene are as follows: (1) 250 g of hydroxyl-terminated polybutadiene ((a+c) / (a+b+c)=0.85, b / (a+b+c)=0.15, hydroxyl value 2.0 mmol / g), 400 g of N,N-dimethylformamide, 5.0 g of boron trifluoride ether solution, and 0.5 g of 2,6-di-tert-butyl-p-cresol were added to the reactor. The reactor was kept under a nitrogen atmosphere. The mixture was stirred and kept at 100°C. 61.0 g of glycidyl acrylate was added to the dropping tank. The dropping time was 2 h. The reaction system temperature was kept at 60°C and the reaction was continued for 3 h to obtain intermediate product 1.

[0070] (2) Add 2.5 g of boron trifluoride diethyl ether solution and 0.1 g of 2,6-di-tert-butyl-p-cresol to intermediate product 1, and continue to add 80 g of N,N-dimethylformamide and 92.2 g of an epoxy compound containing a bridged ring structure. A mixture of (k=1, R2 and R3 are CH3) was added dropwise for 3 h, the reaction temperature was maintained at 80℃, the reaction was carried out for 5 h, and then cooled to obtain intermediate product 2.

[0071] (3) Adjust the pH of intermediate 2 to 3.0 with acetic acid / sodium acetate buffer solution, and then add 5.5 g of methacryloyloxysilane ( Stir at 25°C for 5 h, then raise the temperature to 100°C, hold for 1 h, and then cool to obtain intermediate product 3.

[0072] (4) Intermediate product 3 was washed once with 2000 mL of 0.5% sodium hydroxide aqueous solution, twice with 2000 mL of saturated saline solution, and three times with 2000 mL of deionized water. It was then dried with anhydrous magnesium sulfate, filtered, and the solvent was removed by rotary evaporation to obtain modified hydroxyl-terminated polybutadiene F.

[0073] Example 7: Preparation of modified hydroxyl-terminated polybutadiene The preparation steps of modified hydroxyl-terminated polybutadiene are as follows: (1) 250 g of hydroxyl-terminated polybutadiene ((a+c) / (a+b+c)=0.75, b / (a+b+c)=0.25, hydroxyl value 0.8 mmol / g), 250 g of cyclohexanone, 7.5 g of boron trifluoride ether solution, and 0.75 g of hydroquinone were added to the reactor respectively. The reactor was kept under a nitrogen atmosphere, stirred and kept at 60°C. 28.4 g of glycidyl methacrylate was added to the dropping tank and dropped for 1 h. The reaction system was kept at 60°C and the reaction was continued for 3 h to obtain intermediate product 1.

[0074] (2) Add 1.5 g of boron trifluoride ether solution and 0.075 g of hydroquinone to intermediate product 1, and continue to add 100 g of cyclohexanone and 48.5 g of an epoxy compound containing a bridged ring structure. The mixture of (k=2) was added dropwise over 3 hours, and the reaction temperature was maintained at 110°C for 2 hours. After cooling, intermediate product 2 was obtained.

[0075] (3) Adjust the pH of intermediate 2 to 4.5 with acetic acid / sodium acetate buffer solution, and then add 4.6 g of methacryloyloxysilane ( Stir at 25°C for 5 h, then raise the temperature to 100°C, maintain for 3 h, and then cool to obtain intermediate product 3.

[0076] (4) The intermediate product 3 was washed once with 800 mL of 2.0% sodium hydroxide aqueous solution, twice with 800 mL of saturated saline solution, and once with 800 mL of deionized water. It was then dried with anhydrous magnesium sulfate, filtered, and the solvent was removed by rotary evaporation to obtain modified hydroxyl-terminated polybutadiene G.

[0077] Example 8: Preparation of modified hydroxyl-terminated polybutadiene The preparation steps of modified hydroxyl-terminated polybutadiene are as follows: (1) 250 g of hydroxyl-terminated polybutadiene ((a+c) / (a+b+c)=0.80, b / (a+b+c)=0.20, hydroxyl value 1.0 mmol / g), 300 g of cyclohexanone, 2.5 g of boron trifluoride ether solution, and 1.25 g of hydroquinone were added to the reactor respectively. The reactor was kept under a nitrogen atmosphere, stirred and kept at 80°C. 33.8 g of glycidyl methacrylate was added to the dropping tank and dropped for 1 h. The reaction system was kept at 60°C and the reaction was continued for 3 h to obtain intermediate product 1.

[0078] (2) Add 1.25 g of boron trifluoride ether solution and 0.13 g of hydroquinone to the reaction end solution from step (1), and continue to add 60 g of cyclohexanone and 61.0 g of an epoxy compound containing a bridged ring structure. A mixture of (k=2, R2 is CH3) was added dropwise for 3 h, the reaction temperature was maintained at 80℃, the reaction was carried out for 5 h, and then cooled to obtain intermediate product 2.

[0079] (3) Adjust the pH of intermediate 2 to 4.0 with acetic acid / sodium acetate buffer solution, and then add 4.5 g of methacryloyloxysilane ( Stir at 45°C for 1 h, then raise the temperature to 100°C, maintain for 5 h, and then cool to obtain intermediate product 3.

[0080] (4) The intermediate product 3 was washed once with 1200 mL of 0.5% sodium hydroxide aqueous solution, twice with 1200 mL of saturated saline solution, and three times with 1200 mL of deionized water. It was then dried with anhydrous magnesium sulfate, filtered, and the solvent was removed by rotary evaporation to obtain modified hydroxyl-terminated polybutadiene H.

[0081] Example 9: Preparation of modified hydroxyl-terminated polybutadiene The preparation steps of modified hydroxyl-terminated polybutadiene are as follows: (1) 250 g of hydroxyl-terminated polybutadiene ((a+c) / (a+b+c)=0.85, b / (a+b+c)=0.15, hydroxyl value 2.0 mmol / g), 400 g of cyclohexanone, 3 g of boron trifluoride ether solution, and 0.3 g of hydroquinone were added to the reactor respectively. The reactor was kept under a nitrogen atmosphere. The mixture was stirred and the temperature was kept at 60~100℃. 67.7 g of glycidyl methacrylate was added to the dropping tank. The dropping time was 2 h. The reaction system temperature was kept at 60℃ and the reaction was continued for 3 h to obtain intermediate product 1.

[0082] (2) Add 0.6 g of boron trifluoride ether solution and 0.06 g of hydroquinone to intermediate product 1, and continue to add 80 g of cyclohexanone and 128.8 g of an epoxy compound containing a bridged ring structure. A mixture of (k=2, R2 and R3 are CH3) was added dropwise for 3 h, the reaction temperature was maintained at 110℃, the reaction was carried out for 2 h, and then cooled to obtain intermediate product 2.

[0083] (3) Adjust the pH of intermediate 2 to 3.5 with acetic acid / sodium acetate buffer solution, and then add 9.06 g of methacryloyloxysilane ( Stir at 40℃ for 2 h, then raise the temperature to 100~110℃, maintain for 1-5 h and then cool to obtain intermediate product 3.

[0084] (4) The intermediate product 3 was washed once with 3000 mL of 0.5% sodium hydroxide aqueous solution, twice with 3000 mL of saturated saline solution, and twice with 3000 mL of deionized water. It was then dried with anhydrous magnesium sulfate, filtered, and the solvent was removed by rotary evaporation to obtain modified hydroxyl-terminated polybutadiene J.

[0085] Example 10: Preparation of modified hydroxyl-terminated polybutadiene The specific implementation method is the same as in Example 4, except that the non-bridged ring structure compound participates in the epoxidation reaction, i.e., step (2) is omitted, while the remaining steps remain the same. Modified hydroxyl-terminated polybutadiene K is prepared by the following steps: (1) 250 g of hydroxyl-terminated polybutadiene ((a+c) / (a+b+c)=0.75, b / (a+b+c)=0.25, hydroxyl value 0.8 mmol / g), 300 g of xylene, 1.25 g of boron trifluoride tetrahydrofuran solution, and 0.25 g of 2,6-di-tert-butyl-p-cresol were added to the reactor. The reactor was kept under a nitrogen atmosphere. The mixture was stirred and kept at a temperature of 60°C. 28.3 g of glycidyl methacrylate was added to the dropping tank. The dropping time was 1 h. The reaction system was kept at a temperature of 60°C and the reaction was continued for 3 h to obtain intermediate product 1.

[0086] (2) Adjust the pH of intermediate 1 to 4.0 with acetic acid / sodium acetate buffer solution, and then add 4.6 g of methacryloyloxysilane ( Stir at 25°C for 5 h, then raise the temperature to 100°C, hold for 2 h, and then cool to obtain intermediate product 2.

[0087] (3) The intermediate product 2 was washed once with 1600 mL of 0.5% sodium hydroxide aqueous solution, twice with 1600 mL of saturated saline solution, and once with 1600 mL of deionized water. It was then dried with anhydrous magnesium sulfate, filtered, and the solvent was removed by rotary evaporation to obtain modified hydroxyl-terminated polybutadiene K.

[0088] Example 11: Preparation of modified hydroxyl-terminated polybutadiene The difference between this preparation and Example 4 of the modified hydroxyl-terminated polybutadiene preparation is that no silane coupling agent is involved in the reaction, i.e., step (3) is omitted, while the remaining steps remain the same, to prepare modified hydroxyl-terminated polybutadiene L. The specific steps are as follows: (1) 250 g of hydroxyl-terminated polybutadiene ((a+c) / (a+b+c)=0.75, b / (a+b+c)=0.25, hydroxyl value 0.8 mmol / g), 300 g of xylene, 1.25 g of boron trifluoride tetrahydrofuran solution, and 0.25 g of 2,6-di-tert-butyl-p-cresol were added to the reactor. The reactor was kept under a nitrogen atmosphere. The mixture was stirred and kept at a temperature of 60°C. 28.3 g of glycidyl methacrylate was added to the dropping tank. The dropping time was 1 h. The reaction system was kept at a temperature of 60°C and the reaction was continued for 3 h to obtain intermediate product 1.

[0089] (2) Add 0.25 g of boron trifluoride tetrahydrofuran solution and 0.05 g of 2,6-di-tert-butyl-p-cresol to intermediate product 1, and continue to add 100 g of xylene and 35.0 g of an epoxy compound containing a bridged ring structure. The mixture of (k=1) was added dropwise over 2 hours, and the reaction temperature was maintained at 80°C. After 2 hours of reaction, the mixture was cooled to obtain intermediate product 2.

[0090] (3) The intermediate product 2 was washed once with 1600 mL of 0.5% sodium hydroxide aqueous solution, twice with 1600 mL of saturated saline solution, and once with 1600 mL of deionized water. It was then dried with anhydrous magnesium sulfate, filtered, and the solvent was removed by rotary evaporation to obtain modified hydroxyl-terminated polybutadiene L.

[0091] Example 12: Preparation of Environmentally Friendly Insulating Coating The preparation of environmentally friendly insulating coatings includes the following steps: Add modified hydroxyl-terminated polybutadiene oligomer A and reactive diluent to a high-speed mixer, control the stirring speed at 1000 rpm, and stir for 5 minutes to disperse until uniform; then maintain the stirring speed at 1200 rpm, continue to add photoinitiator and leveling agent, and stir for 15 minutes; then adjust the stirring speed to 1500 rpm, continue to add pigment, and stir for 30 minutes to form a premix; The premixed material is transferred to a grinding equipment for grinding until the particle size is less than 15 μm. It is then filtered through a 150~250 mesh filter to obtain an environmentally friendly insulating coating.

[0092] Each component, calculated per 100 parts by total weight, includes the following raw materials: Modified hydroxyl-terminated polybutadiene A 55 parts; reactive diluent La ( 32 portions; reactive diluent Lb ( 8 parts; 4 parts photoinitiator 1173; 0.5 parts pigment (US058); 0.5 parts leveling agent (TEGO Glide410).

[0093] Example 13: Preparation of Environmentally Friendly Insulating Coating The preparation of environmentally friendly insulating coatings includes the following steps: Add modified hydroxyl-terminated polybutadiene oligomer B and reactive diluent to a high-speed mixer, control the stirring speed at 1000 rpm, and stir for 10 min to disperse until uniform; then, while maintaining the stirring speed at 1000 rpm, continue to add photoinitiator and leveling agent, and stir for 10 min; then adjust the stirring speed to 1200 rpm, continue to add pigment, and stir for 15 min to form a premix; The premixed material is transferred to a grinding equipment for grinding until the particle size is less than 15 μm. It is then filtered through a 150~250 mesh filter to obtain an environmentally friendly insulating coating.

[0094] Each component, calculated per 100 parts by total weight, includes the following raw materials: Modified hydroxyl-terminated polybutadiene B 60 parts; reactive diluent La ( 28 portions; reactive diluent Lb ( 7 parts; 3 parts photoinitiator 184; 1.8 parts pigment (US058); 0.2 parts leveling agent (TEGOGlide 410).

[0095] Example 14: Preparation of Environmentally Friendly Insulating Coating The preparation of environmentally friendly insulating coatings includes the following steps: Add modified hydroxyl-terminated polybutadiene oligomer C and reactive diluent to a high-speed mixer, control the stirring speed at 1200 rpm, and stir for 5 minutes to disperse until uniform; then, while maintaining the stirring speed at 1200 rpm, continue to add photoinitiator and leveling agent, and stir for 15 minutes; then adjust the stirring speed to 1500 rpm, continue to add pigment, and stir for 15 minutes to form a premix; The premixed material is transferred to a grinding equipment for grinding until the particle size is less than 15 μm. It is then filtered through a 150~250 mesh filter to obtain an environmentally friendly insulating coating.

[0096] Each component, calculated per 100 parts by total weight, includes the following raw materials: Modified hydroxyl-terminated polybutadiene C 65 parts; reactive diluent La ( 24 portions; reactive diluent Lb ( 6 parts; 4.4 parts photoinitiator 651; 0.5 parts pigment (US058); 0.1 parts leveling agent (TEGOGlide 410).

[0097] Example 15: Preparation of Environmentally Friendly Insulating Coating The preparation of environmentally friendly insulating coatings includes the following steps: Add modified hydroxyl-terminated polybutadiene oligomer D and reactive diluent to a high-speed mixer, control the stirring speed at 1000 rpm, and stir for 10 min to disperse until uniform; then, while maintaining the stirring speed at 1000 rpm, continue to add photoinitiator and leveling agent, and stir for 15 min; then adjust the stirring speed to 1200 rpm, continue to add pigment, and stir for 15 min to form a premix; The premixed material is transferred to a grinding equipment for grinding until the particle size is less than 15 μm. It is then filtered through a 150~250 mesh filter to obtain an environmentally friendly insulating coating.

[0098] Each component, calculated per 100 parts by total weight, includes the following raw materials: Modified hydroxyl-terminated polybutadiene D 68 parts; reactive diluent La ( 16.8 parts; reactive diluent Lb ( 11.2 parts; 2 parts photoinitiator TPO; 1.5 parts pigment (US237); 0.5 parts leveling agent (TEGOGlide 450).

[0099] Example 16: Preparation of Environmentally Friendly Insulating Coating The preparation of environmentally friendly insulating coatings includes the following steps: Add modified hydroxyl-terminated polybutadiene oligomer E and reactive diluent to a high-speed mixer, control the stirring speed at 1200 rpm, and stir for 10 min to disperse until uniform; then, while maintaining the stirring speed at 1200 rpm, continue to add photoinitiator and leveling agent, and stir for 10 min; then adjust the stirring speed to 1400 rpm, continue to add pigment, and stir for 15 min to form a premix; The premixed material is transferred to a grinding equipment for grinding until the particle size is less than 15 μm. It is then filtered through a 150~250 mesh filter to obtain an environmentally friendly insulating coating.

[0100] Each component, calculated per 100 parts by total weight, includes the following raw materials: Modified hydroxyl-terminated polybutadiene E 63 parts; reactive diluent La ( 15 parts; reactive diluent Lb ( 15 parts of photoinitiator 819; 5 parts of pigment (US237); 1.5 parts of leveling agent (TEGOGlide 450).

[0101] Example 17: Preparation of Environmentally Friendly Insulating Coating The preparation of environmentally friendly insulating coatings includes the following steps: Add modified hydroxyl-terminated polybutadiene oligomer F and reactive diluent to a high-speed mixer, control the stirring speed at 1000 rpm, and stir for 10 min to disperse until uniform; then, while maintaining the stirring speed at 1000 rpm, continue to add photoinitiator and leveling agent, and stir for 10 min; then adjust the stirring speed to 1200 rpm, continue to add pigment, and stir for 30 min to form a premix; The premixed material is transferred to a grinding equipment for grinding until the particle size is less than 15 μm. It is then filtered through a 150~250 mesh filter to obtain an environmentally friendly insulating coating.

[0102] Each component, calculated per 100 parts by total weight, includes the following raw materials: Modified hydroxyl-terminated polybutadiene F 58 parts; reactive diluent La ( 25.2 parts; reactive diluent Lb ( 10.8 parts; 4.8 parts of photoinitiator 910; 1 part of pigment (US237); 0.2 parts of leveling agent (HY-100).

[0103] Example 18: Preparation of Environmentally Friendly Insulating Coating The preparation of environmentally friendly insulating coatings includes the following steps: Add modified hydroxyl-terminated polybutadiene oligomer G and reactive diluent to a high-speed mixer, control the stirring speed at 1200 rpm, and stir for 10 min to disperse until uniform; then, while maintaining the stirring speed at 1200 rpm, continue to add photoinitiator and leveling agent, and stir for 15 min; then adjust the stirring speed to 1400 rpm, continue to add pigment, and stir for 20 min to form a premix; The premixed material is transferred to a grinding equipment for grinding until the particle size is less than 15 μm. It is then filtered through a 150~250 mesh filter to obtain an environmentally friendly insulating coating.

[0104] Each component, calculated per 100 parts by total weight, includes the following raw materials: 70 parts of modified hydroxyl-terminated polybutadiene G; reactive diluent La ( 15 parts; reactive diluent Lb ( 10 parts; 3 parts photoinitiator 651; 1.8 parts pigment (UV15:4 blue-20); 0.2 parts leveling agent (HY-100).

[0105] Example 19: Preparation of Environmentally Friendly Insulating Coating The preparation of environmentally friendly insulating coatings includes the following steps: Add modified hydroxyl-terminated polybutadiene oligomer H and reactive diluent to a high-speed mixer, control the stirring speed at 1000 rpm, and stir for 10 min to disperse until uniform; then, while maintaining the stirring speed at 1000 rpm, continue to add photoinitiator and leveling agent, and stir for 15 min; then adjust the stirring speed to 1200 rpm, continue to add pigment, and stir for 30 min to form a premix; The premixed material is transferred to a grinding equipment for grinding until the particle size is less than 15 μm. It is then filtered through a 150-250 mesh filter to obtain an environmentally friendly insulating coating.

[0106] Each component, calculated per 100 parts by total weight, includes the following raw materials: Modified hydroxyl-terminated polybutadiene H 66 parts; reactive diluent La ( 15 parts; reactive diluent Lb ( 14 parts; 3 parts photoinitiator 907; 1.5 parts pigment (UV15:4 blue-20); 0.5 parts leveling agent (BYK379).

[0107] Example 20: Preparation of Environmentally Friendly Insulating Coating The preparation of environmentally friendly insulating coatings includes the following steps: Add modified hydroxyl-terminated polybutadiene oligomer J and reactive diluent to a high-speed mixer, control the stirring speed at 1200 rpm, and stir for 5 minutes to disperse until uniform; then, while maintaining the stirring speed at 1200 rpm, continue to add photoinitiator and leveling agent, and stir for 15 minutes; then adjust the stirring speed to 1400 rpm, continue to add pigment, and stir for 15 minutes to form a premix; The premixed material is transferred to a grinding equipment for grinding until the particle size is less than 15 μm. It is then filtered through a 150~250 mesh filter to obtain an environmentally friendly insulating coating.

[0108] Each component, calculated per 100 parts by total weight, includes the following raw materials: Modified hydroxyl-terminated polybutadiene J 64 parts; reactive diluent La ( 22 portions; reactive diluent Lb ( 9 parts; photoinitiator EDB 3.5 parts; pigment (UV15:4 blue-20) 1 part; leveling agent (BYK379) 0.5 parts.

[0109] Comparative Example 1: Preparation of Environmentally Friendly Insulating Coating The specific implementation method is the same as in Example 15, except that the modified hydroxyl-terminated polybutadiene oligomer D is replaced with the modified hydroxyl-terminated polybutadiene K prepared in Example 10, while the other steps remain the same, and an environmentally friendly insulating coating is prepared.

[0110] Comparative Example 2: Preparation of Environmentally Friendly Insulating Coating The specific implementation method is the same as in Example 15, except that the modified hydroxyl-terminated polybutadiene oligomer D is replaced with the modified hydroxyl-terminated polybutadiene L prepared in Example 11, while the other steps remain the same, and an environmentally friendly insulating coating is prepared.

[0111] Comparative Example 3: Preparation of Environmentally Friendly Insulating Coating The specific implementation method is the same as in Example 16, except that the amount of reactive diluent added is changed, that is, reactive diluent La ( 12 parts, reactive diluent Lb ( 18 portions; the remaining steps remain the same to prepare an environmentally friendly insulating coating.

[0112] Example 21: Performance Measurement The environmentally friendly insulating coatings prepared in Examples 12-20 and Comparative Examples 1-3 were placed in a UV curing machine and cured under UVA light intensity of 1900 mW / cm². 2 The light dose is 2200 mJ / cm 2 The curing time was 40 seconds. The properties of the cured coating were measured. The results are shown in Table 1.

[0113] Table 1 Summary of Performance Test Results

[0114] As can be seen from Table 1, the insulating coating prepared by using specially modified hydroxyl-terminated polybutadiene, acrylate soft and hard monomers with bridged ring structure, pigments and leveling agents under the action of photoinitiators has excellent insulation, mechanical strength, heat resistance and aging resistance.

[0115] Through Example 15 and Comparative Example 1, it was found that the introduction of bridged ring structural units into the modified hydroxyl-terminated polybutadiene significantly improves the insulation, hardness, adhesion, wear resistance, and heat resistance of the insulating coating.

[0116] Through Example 15 and Comparative Example 2, it was found that the introduction of silicon-containing structural units into the modified hydroxyl-terminated polybutadiene also significantly helps to improve the insulation, adhesion, wear resistance, heat resistance and other properties of the insulating coating.

[0117] Through Example 16 and Comparative Example 3, it was found that excessively high levels of alicyclic acrylate soft monomers with ethoxylated bridged ring structures can lead to a decrease in the mechanical strength, heat resistance, and other properties of the coating.

[0118] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Anyone skilled in the art can make various modifications and alterations without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be determined by the claims.

Claims

1. A modified hydroxyl-terminated polybutadiene, characterized in that, The structural formula of the modified hydroxyl-terminated polybutadiene is shown in Formula I: ； In the formula, R1 is hydrogen or methyl, R2 is hydrogen or methyl, R3 is hydrogen or methyl, and k is 0, 1, or 2.

2. The modified hydroxyl-terminated polybutadiene according to claim 1, characterized in that, The preparation method of the modified hydroxyl-terminated polybutadiene includes the following steps: (1) Add hydroxyl-terminated polybutadiene, solvent, catalyst and polymerization inhibitor to the reactor respectively, maintain a nitrogen atmosphere in the reactor, stir and maintain the temperature at 60~100℃, add glycidyl methacrylate to the dropping tank, drop for 1~3 h, maintain the reaction system temperature at 40~60℃ for reaction, and continue the reaction for 1~3 h to obtain intermediate product 1; (2) Add catalyst and polymerization inhibitor to intermediate product 1, and continue to add solvent and a mixture of epoxy compound containing bridged ring structure dropwise for 1-3 h, maintain reaction temperature at 80-110℃, react for 2-5 h, cool, and obtain intermediate product 2; (3) Adjust the pH of intermediate product 2 to 3.0~4.5 with acetic acid / sodium acetate buffer solution, then add silane coupling agent, stir at 25~45℃ for 1~5 h, then heat to 100~110℃, maintain for 1~5 h, and cool to obtain intermediate product 3; (4) After washing, drying, filtering and rotary evaporating intermediate product 3, modified hydroxyl-terminated polybutadiene is obtained.

3. The modified hydroxyl-terminated polybutadiene according to claim 2, characterized in that, The structural formula of the hydroxyl-terminated polybutadiene is shown in Formula II: Among them, (a+c) / (a+b+c)=0.75~0.85, b / (a+b+c)=0.15~0.25, and the hydroxyl value is 0.8~2.0 mmol / g; Optionally, the solvent is one of toluene, xylene, N,N-dimethylformamide, and cyclohexanone; the amount of solvent added is 1 to 2 times the mass of the hydroxyl-terminated polybutadiene. Optionally, the catalyst is a boron trifluoride tetrahydrofuran solution or a boron trifluoride diethyl ether solution; the amount of catalyst added is 0.2% to 2.0% of the mass of the hydroxyl-terminated polybutadiene. Optionally, the polymerization inhibitor is one of p-methoxyphenol, 2,6-di-tert-butyl-p-cresol, or hydroquinone; the amount of polymerization inhibitor added is 0.1-0.5% of the mass of the hydroxyl-terminated polybutadiene. Optionally, the silane coupling agent is a methacryloyloxyalkylsilane with the structure shown in formulas X1 to X3: ； Where R' is , or , R'' is R''' is ; Optionally, the epoxide containing the bridged ring structure has the structure shown in Formula III: Where k = 0, 1, or 2; R2 and R3 are H or CH3; Optionally, the amount of solvent added in step (2) is 20-50% of the mass of solvent added in step (1); the amount of catalyst added in step (2) is 20-50% of the mass of catalyst added in step (1); and the amount of polymerization inhibitor added in step (2) is 10-20% of the mass of polymerization inhibitor added in step (1).

4. The modified hydroxyl-terminated polybutadiene according to claim 2, characterized in that, The amounts of hydroxyl-terminated polybutadiene, glycidyl (meth)acrylate, bridged ring-structured epoxy compound, and silane coupling agent involved in steps (1), (2), and (3) are as follows: n (molar amount of hydroxyl-terminated polybutadiene): n (molar amount of glycidyl methacrylate): n (molar amount of epoxy compound with bridged ring structure): n (molar amount of silane coupling agent) = (1.005~1.05): 1:1: (0.05~0.10).

5. A method for preparing an environmentally friendly insulating coating, characterized in that, The modified hydroxyl-terminated polybutadiene described in claim 1 is used to prepare the product, comprising the following steps: Add modified hydroxyl-terminated polybutadiene and reactive diluent to the mixer, control the stirring speed at 1000~1200 rpm, and stir for 5~10 min to disperse until uniform; then, while maintaining the stirring speed at 1000~1200 rpm, continue to add photoinitiator and leveling agent, and stir for 5~15 min; then adjust the stirring speed to 1200~1500 rpm, continue to add pigment, and stir for 15~30 min to form a premix; The premixed material is ground to a particle size of less than 15 μm and filtered through a 150-250 mesh filter to obtain an environmentally friendly insulating coating.

6. The method according to claim 5, characterized in that, The mass ratio of modified hydroxyl-terminated polybutadiene, reactive diluent, photoinitiator, pigment, and leveling agent is 55~70:25~40:2~5:0.5~2:0.1~0.

5.

7. The method according to claim 5, characterized in that, The reactive diluent is two alicyclic acrylate monomers, La and Lb, containing bridged ring structures, with a mass ratio of La to Lb of 0.5~0.8:0.2~0.5; La structure (Formula IV): ， R4 and R5 are H or CH3, k = 0, 1 or 2; Lb structure (Form V): ， R6 and R7 are H or CH3, and k = 0, 1 or 2.

8. The method according to claim 5, characterized in that, The photoinitiators include one or more of the following: 2-hydroxy-2-methylphenylacetone (photoinitiator 1173), 1-hydroxycyclohexylphenyl ketone (photoinitiator 184), α,α-dimethoxy-α-phenylacetophenone (photoinitiator 651), diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (photoinitiator TPO), phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide (photoinitiator 819), 2-isopropylthioxanthone (photoinitiator ITX), ethyl 4-dimethylaminobenzoate (photoinitiator EDB), 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone (photoinitiator 910), 2,2-dimethoxy-2-phenylacetophenone (photoinitiator 651), and 2-methyl-1-(4-methylthiophenyl)-2-morpholino-1-propanone (photoinitiator 907). Optionally, the leveling agent is a polyether siloxane copolymer, commercially available brands such as TEGO Glide 410, TEGO Glide 450, HY-100, and BYK379. Optionally, the pigment is a UV blue pigment, commercially available under the designations US058, US237, and UV15:4 Blue-20.

9. The environmentally friendly insulating coating prepared by any one of the methods described in claims 5 to 8.

10. The application of the modified hydroxyl-terminated polybutadiene of claim 1 or the environmentally friendly insulating coating of claim 9 in the outer insulating layer of new energy batteries.

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