Bi-component polyurethane pouring sealant as well as preparation method and application thereof
By compounding lightweight filler microbeads and microspheres and synergizing soft and hard segment resins, the prepared two-component polyurethane potting compound solves the contradiction between density and mechanical properties, achieving a low viscosity, low density, high strength and high aging resistance potting compound, meeting the high performance requirements of new energy batteries, electronic packaging and aerospace fields.
Patent Information
- Application Number
- CN202510808418.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-17
- Publication Date
- 2025-09-12
AI Technical Summary
In the existing technology, the potting materials have bottlenecks such as the contradiction between density and mechanical properties, poor glue leveling, and poor long-term aging resistance, which makes it difficult to meet the high performance requirements of new energy batteries, electronic packaging and aerospace fields.
A two-component polyurethane potting compound is prepared by compounding lightweight filler microbeads and microspheres, combining the synergistic effect of soft and hard segment resins. Through specific raw material proportions and process flow, the viscosity and density are reduced, while the mechanical properties and anti-aging properties are improved.
A low-viscosity and low-density two-component polyurethane potting adhesive has been achieved, with a density of less than 0.8 g/cm3, a viscosity of less than 4000 mPa·s, a shear strength after curing of more than 6 MPa, an elongation at break of more than 200%, and a double 85 aging attenuation of less than 5% after 1000 h, meeting the requirements of low viscosity, low density, high strength and high weather resistance for the new potting adhesive.
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Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of potting materials, and in particular to a two-component polyurethane potting adhesive and a preparation method and application thereof. Background Art
[0002] With the global energy transition and the accelerating trend toward miniaturization of electronic devices, the application of potting materials in fields such as new energy batteries, electronic packaging, and aerospace continues to expand. This has also led to several emerging demands: the need for lightweight power battery packs to enhance vehicle range; the need for low-viscosity and high self-leveling properties for the potting and filling of precision equipment such as electronic appliances; the need for high weather resistance, depending on the application scenario; and the need for environmental compliance to meet EU REACH regulations restricting volatile organic compound (VOC) emissions, necessitating the development of solvent-free or low-toxic formulations. Low-density two-component polyurethane potting compounds, through their molecular structure design and process innovations, have become an ideal candidate for addressing these challenges.
[0003] However, the existing technology still has bottlenecks such as the contradiction between density and mechanical properties, poor glue leveling, and poor long-term aging resistance. Summary of the Invention
[0004] Based on the above description, the present invention provides a two-component polyurethane potting adhesive and its preparation method and application to solve the problem of how to reduce the viscosity and density of the potting adhesive and improve the anti-aging performance of the potting adhesive while maintaining the mechanical properties of the glue.
[0005] The technical solution of the present invention to solve the above technical problems is as follows: The present invention provides a two-component polyurethane potting adhesive, comprising component A and component B; The A comprises the following raw materials in parts by weight: 0-30 parts of polyester polyol, 0-30 parts of polyether polyol, 0-20 parts of castor oil, 5-20 parts of diluent, 5-25 parts of light filler, 0.1-5 parts of water remover, 0.1-0.5 parts of dispersant, 0.1-0.5 parts of pigment and filler; Described B comprises the following raw materials in parts by weight: 5-20 parts of polyether polyol, 10-60 parts of isocyanate, 10-20 parts of diluent, 5-25 parts of lightweight filler, 0.1-5 parts of water scavenger, 0.1-0.5 parts of dispersant, and 0.1-0.5 parts of pigment and filler.
[0006] Furthermore, the volume ratio of component A to component B is 1:0.5~1.5.
[0007] Furthermore, in the component A, the hydroxyl value of the polyester polyol is 195 mg KOH / g, and the hydroxyl value of the polyether polyol is 225 mg KOH / g; in the component B, the hydroxyl value of the polyether polyol is 56 mg KOH / g.
[0008] Furthermore, the lightweight filler is a mixture of hollow glass microspheres and polystyrene microspheres.
[0009] Furthermore, in the lightweight filler, the mass ratio of hollow glass microspheres to polystyrene microspheres is (14-18): (0.4-0.5).
[0010] Furthermore, in the component B, the isocyanate includes one or more of 4,4'-methylenebis(cyclohexyl isocyanate), diphenylmethane diisocyanate, isophorone diisocyanate, and polymethylene polyphenyl isocyanate.
[0011] Furthermore, in the component A, the diluent is dipropylene glycol; In the component B, the diluent is triisopropylphenyl phosphate.
[0012] Further, the dispersant includes a polyurea compound; The dehydrating agent is molecular sieve or oxazolidine.
[0013] The present invention also provides a method for preparing the aforementioned two-component polyurethane potting adhesive, comprising the following steps: The polyester polyol, polyether polyol, castor oil, diluent, light filler, water scavenger, dispersant and pigment and filler are mixed after vacuuming to obtain component A; The polyether polyol and isocyanate are mixed and heated to cause a polymerization reaction to obtain a prepolymer, and the prepolymer, isocyanate, diluent, lightweight filler, water scavenger, dispersant and pigment and filler are vacuumed and mixed to obtain component B; Component A and component B are mixed in a volume ratio of 1:1 to obtain a two-component polyurethane potting adhesive.
[0014] The present invention also proposes an application of the aforementioned two-component polyurethane potting adhesive in the fields of electronic appliances, new energy vehicles or aerospace.
[0015] Compared with the prior art, the technical solution of this application has the following beneficial technical effects: 1. The present invention uses a combination of lightweight filler microbeads and microspheres, as well as the synergistic effect of soft and hard segment resins, which not only effectively reduces the viscosity and density of the glue, but also balances the contradiction between density and mechanical properties, and has multiple excellent properties. 2. The density of the glue provided by the present invention after mixing is less than 0.8g / cm 3The viscosity after mixing is less than 4000mPa·s, the shear strength after curing is greater than 6MPa, the elongation at break is greater than 200%, and the attenuation of double 85 aging for 1000h is less than 5%, which meets the performance requirements of low viscosity, low density and anti-aging of the new potting glue. DETAILED DESCRIPTION
[0016] To facilitate understanding of the present application, the present application will be described in more detail below. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive.
[0017] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application pertains. The terms used herein in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application.
[0018] When used herein, the singular forms "a", "an", and "the" may also include the plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "include / comprise" or "have" and the like specify the presence of stated features, integers, steps, operations, components, parts, or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, integers, steps, operations, components, parts, or combinations thereof.
[0019] With the global energy transition and the accelerating trend toward miniaturization of electronic devices, the application of potting materials in fields such as new energy batteries, electronic packaging, and aerospace continues to expand. This has also led to several emerging demands: lightweighting of power battery packs to enhance vehicle range; potting and filling of precision equipment such as electronic appliances requires adhesives with low viscosity and high self-leveling properties to meet the requirements of precision potting; high weather resistance is required depending on the application scenario; and environmental compliance is required to meet EU REACH regulations restricting volatile organic compound (VOC) emissions, necessitating the development of solvent-free or low-toxicity formulations. Low-density two-component polyurethane potting adhesives, through molecular structure design and process innovation, have become an ideal candidate to address these challenges. However, existing technologies still face bottlenecks such as the conflict between density and mechanical properties, poor adhesive leveling, and poor long-term aging resistance.
[0020] Patent CN 117866582A discloses a low-density polyurethane potting adhesive, its preparation method, and application. By modifying the surface of hollow microspheres, this adhesive overcomes the problem of reduced adhesive adhesion and storage stability caused by the addition of hollow microspheres. However, the viscosity of the adhesive components A and B ranges from 16,000 to 20,000 mPa·s, making it difficult to perform potting applications.
[0021] Patent CN 115772380B discloses a method for preparing a low-density potting compound. By using a specific vinyl-terminated polyurethane prepolymer, combined with specific preparation processes, conditions, and parameters, a low-density potting compound with excellent performance is obtained. However, the density of the glue is greater than 0.87 g / cm 3 The density is limited and does not meet the demand for further lightweighting.
[0022] To this end, the present invention provides a low-viscosity, low-density two-component polyurethane potting adhesive with multiple performance advantages. The two-component polyurethane potting adhesive has a low density, and the density after mixing and curing is less than 0.8 g / cm 3 , which can meet the lightweight requirements of power battery packs; the two-component polyurethane potting adhesive has a low viscosity, with a viscosity of less than 4000 mPa·s after mixing, and has high self-leveling properties, meeting the requirements of precision potting; the two-component polyurethane potting adhesive has high strength and high toughness, with a shear strength of more than 6MPa and an elongation at break of more than 200% after curing, balancing density and mechanical properties to meet high performance requirements, and the attenuation of double 85 aging for 1000 hours is less than 5%, with excellent weather resistance.
[0023] In view of this, the present invention proposes a two-component polyurethane potting adhesive, comprising component A and component B; The A comprises the following raw materials in parts by weight: 0-30 parts of polyester polyol, 0-30 parts of polyether polyol, 0-20 parts of castor oil, 5-20 parts of diluent, 5-25 parts of light filler, 0.1-5 parts of water remover, 0.1-0.5 parts of dispersant, 0.1-0.5 parts of pigment and filler; Described B comprises the following raw materials in parts by weight: 5-20 parts of polyether polyol, 10-60 parts of isocyanate, 10-20 parts of diluent, 5-25 parts of lightweight filler, 0.1-5 parts of water scavenger, 0.1-0.5 parts of dispersant, and 0.1-0.5 parts of pigment and filler.
[0024] In the technical solution of the present invention, by compounding lightweight filler microbeads and microspheres and synergizing the soft and hard segment resins, the viscosity and density of the glue are effectively reduced, the contradiction between density and mechanical properties is balanced, and multiple excellent properties are achieved.
[0025] Specifically, in some embodiments of the present invention, castor oil (CTO) is extra-grade castor oil purchased from Xinglong New Materials Co., Ltd. or Huanyu Oils & Fats Co., Ltd.
[0026] Furthermore, the volume ratio of component A to component B is 1:0.5~1.5.
[0027] Furthermore, in component A, the hydroxyl value of the polyester polyol is 195 mg KOH / g, and the hydroxyl value of the polyether polyol is 225 mg KOH / g; in component B, the hydroxyl value of the polyether polyol is 56 mg KOH / g.
[0028] It should be noted that the polyether polyols of the component A and the component B may be the same or different. Specifically, in some embodiments of the present invention, in component A, the polyester polyol is ST-1080T, purchased from Nanjing Suterin New Material Technology Co., Ltd., and the polyether polyol is XC-488, purchased from Beijing Baiyuan Chemical Co., Ltd.; in component B, the polyether polyol is DA21, purchased from Shanghai Jingri New Material Technology Co., Ltd.
[0029] Furthermore, the lightweight filler is a mixture of hollow glass microspheres and polystyrene microspheres.
[0030] Specifically, in some embodiments of the present invention, hollow glass microspheres can be HS42K (Zhengzhou Shenglite Hollow Microsphere New Material Co., Ltd.), HS38K (Zhengzhou Shenglite Hollow Microsphere New Material Co., Ltd.), 32P (Sinco Ma'anshan Mining Institute New Material Technology Co., Ltd.), 38P (Sinco Ma'anshan Mining Institute New Material Technology Co., Ltd.), KS32 (Anhui Kaisheng Basic Materials Technology Co., Ltd.), KS38 (Anhui Kaisheng Basic Materials Technology Co., Ltd.), H25 (Zhongke Hairui Technology Research Institute Co., Ltd.), and H38 (Zhongke Hairui Technology Research Institute Co., Ltd.); polystyrene microspheres can be FM 9945 (Shanghai Yinman Chemical Co., Ltd.) and MH-60D (Hesongyuan New Materials Co., Ltd.).
[0031] Furthermore, in the lightweight filler, the mass ratio of hollow glass microspheres to polystyrene microspheres is (14-18): (0.4-0.5).
[0032] In the technical solution of the present invention, by adjusting the mass ratio of hollow glass microspheres and polystyrene microspheres, hollow glass microspheres are mainly used in the lightweight filler, and a small amount of polystyrene microspheres are added. This can effectively reduce the overall density of the potting compound without significantly affecting the mechanical properties of the potting compound.
[0033] Furthermore, in the component B, the isocyanate includes one or more of 4,4'-methylenebis(cyclohexyl isocyanate), diphenylmethane diisocyanate (MDI), isophorone diisocyanate (IPDI), and polymethylene polyphenyl isocyanate.
[0034] Specifically, in some embodiments of the present invention, the isocyanate is polymethylene polyphenyl isocyanate (PM200) of Wanhua Chemical Group Co., Ltd., carbodiimide-modified 4,4'-diphenylmethane diisocyanate (CDMDI-100L), a mixture of 2,4'-diphenylmethane diisocyanate and 4,4'-diphenylmethane diisocyanate (MDI-50), isophorone diisocyanate (IPDI), and dicyclohexylmethane-4,4'-diisocyanate (HMDI).
[0035] Furthermore, in the component A, the diluent is dipropylene glycol; In the component B, the diluent is triisopropylphenyl phosphate.
[0036] In the technical solution of the present invention, different effects are achieved by using different diluents in component A and component B; dipropylene glycol as a diluent can effectively reduce the viscosity of the polyurethane system, and triisopropylphenyl phosphate as a diluent not only plays a diluting role but also has a good plasticizing effect; the two are used in combination to prepare the potting compound, which can reduce the viscosity of the potting compound without sacrificing mechanical properties.
[0037] Further, the dispersant includes a polyurea compound; The dehydrating agent is molecular sieve or oxazolidine.
[0038] Specifically, in some embodiments of the present invention, the dispersant is a polyurea compound (DCA-6111), purchased from Guangzhou Ruiju Chemical Technology Co., Ltd.; the molecular sieve is type 4A with an average particle size of 5 μm; and the oxazolidine (JH-0187) is purchased from Wuhan Jianghan Chemical.
[0039] The present invention also provides a method for preparing the aforementioned two-component polyurethane potting adhesive, comprising the following steps: The polyester polyol, polyether polyol, castor oil, diluent, light filler, water scavenger, dispersant and pigment and filler are mixed after vacuuming to obtain component A; The polyether polyol and isocyanate are mixed and heated to cause a polymerization reaction to obtain a prepolymer, and the prepolymer, isocyanate, diluent, lightweight filler, water scavenger, dispersant and pigment and filler are vacuumed and mixed to obtain component B; Component A and component B are mixed in a volume ratio of 1:1 to obtain a two-component polyurethane potting adhesive.
[0040] The present invention also proposes an application of the aforementioned two-component polyurethane potting adhesive in the fields of electronic appliances, new energy vehicles or aerospace.
[0041] The technical solutions of the present invention are further described in detail below in conjunction with specific embodiments. It should be understood that the following embodiments are only used to explain the present invention and are not used to limit the present invention.
[0042] In the examples of the present invention, unless otherwise specified, all raw material components are commercially available products well known to those skilled in the art; in the examples of the present invention, unless otherwise specified, the technical means used are conventional means well known to those skilled in the art.
[0043] Example 1 This embodiment provides a low-viscosity and low-density two-component polyurethane potting adhesive, the raw material composition of which is shown in Table 1.
[0044] Table 1 Raw material composition of the potting compound provided in Example 1
[0045] The preparation method of the low-viscosity and low-density two-component polyurethane potting adhesive is as follows: Preparation of component A: weigh the raw materials according to the composition in the table by mass percentage, evacuate the mixture, and stir to disperse evenly; Preparation of component B: The prepolymer is prepared by polymerizing DA21 and CDMDI-100L at a mass ratio of 51:49 at 80°C. Weigh the raw materials according to the composition in the table by mass percentage, evacuate, and stir to disperse evenly. Seal and store component A and component B separately, and mix them in a volume ratio of 1:1 when using. Example 2 This embodiment provides a low-viscosity and low-density two-component polyurethane potting adhesive, the raw material composition of which is shown in Table 2.
[0046] Table 2 Raw material composition of the potting compound provided in Example 2
[0047] The preparation method of the low-viscosity and low-density two-component polyurethane potting adhesive is as follows: Preparation of component A: weigh the raw materials according to the composition in the table by mass percentage, evacuate the mixture, and stir to disperse evenly; Preparation of component B: The prepolymer is prepared by polymerizing DA21 and CDMDI-100L at a mass ratio of 51:49 at 80°C. Weigh the raw materials according to the composition in the table by mass percentage, evacuate, and stir to disperse evenly. Seal and store component A and component B separately, and mix them in a volume ratio of 1:1 when using. Example 3 This embodiment provides a low-viscosity and low-density two-component polyurethane potting adhesive, the raw material composition of which is shown in Table 3.
[0048] Table 3 Raw material composition of the potting compound provided in Example 3
[0049] The preparation method of the low-viscosity and low-density two-component polyurethane potting adhesive is as follows: Preparation of component A: weigh the raw materials according to the composition in the table by mass percentage, evacuate the mixture, and stir to disperse evenly; Preparation of component B: The prepolymer is prepared by polymerizing DA21 and CDMDI-100L at a mass ratio of 51:49 at 80°C. Weigh the raw materials according to the composition in the table by mass percentage, evacuate, and stir to disperse evenly. Seal and store component A and component B separately, and mix them in a volume ratio of 1:1 when using. Comparative Example 1 This comparative example provides a low-viscosity and low-density two-component polyurethane potting adhesive, the raw material composition of which is shown in Table 4.
[0050] Table 4 Raw material composition of the potting compound provided in Comparative Example 1
[0051] The preparation method of the low-viscosity and low-density two-component polyurethane potting adhesive is as follows: Preparation of component A: weigh the raw materials according to the composition in the table by mass percentage, evacuate the mixture, and stir to disperse evenly; Preparation of component B: The prepolymer is prepared by polymerizing DA21 and CDMDI-100L at a mass ratio of 51:49 at 80°C. Weigh the raw materials according to the composition in the table by mass percentage, evacuate, and stir to disperse evenly. Seal and store component A and component B separately, and mix them in a volume ratio of 1:1 when using. Comparative Example 2 This comparative example provides a low-viscosity and low-density two-component polyurethane potting adhesive, the raw material composition of which is shown in Table 5.
[0052] Table 5 Raw material composition of the potting compound provided in Comparative Example 2
[0053] The preparation method of the low-viscosity and low-density two-component polyurethane potting adhesive is as follows: Preparation of component A: weigh the raw materials according to the composition in the table by mass percentage, evacuate the mixture, and stir to disperse evenly; Preparation of component B: The prepolymer is prepared by polymerizing DA21 and CDMDI-100L at a mass ratio of 51:49 at 80°C. Weigh the raw materials according to the composition in the table by mass percentage, evacuate, and stir to disperse evenly. Seal and store component A and component B separately, and mix them in a volume ratio of 1:1 when using. Comparative Example 3 This comparative example provides a low-viscosity and low-density two-component polyurethane potting adhesive, the raw material composition of which is shown in Table 6.
[0054] Table 6 Raw material composition of potting compound provided in Comparative Example 3
[0055] The preparation method of the low-viscosity and low-density two-component polyurethane potting adhesive is as follows: Preparation of component A: weigh the raw materials according to the composition in the table by mass percentage, evacuate the mixture, and stir to disperse evenly; Preparation of component B: The prepolymer is prepared by polymerizing DA21 and CDMDI-100L at a mass ratio of 51:49 at 80°C. Weigh the raw materials according to the composition in the table by mass percentage, evacuate, and stir to disperse evenly. Seal and store component A and component B separately, and mix them in a volume ratio of 1:1 when using. Performance Testing The products obtained from Examples 1 to 3 and Comparative Examples 1 to 3 were tested, and the sample preparation and testing environment was 25±2°C and 50%±5%.
[0056] (1) Viscosity test: Use Brookfield DV-1 rotary viscometer, 3# rotor, 10 rpm to test the viscosity of component A, component B and after mixing; (2) Density test: Use a density cup to test the density of component A, component B, and mixed components; (3) Room temperature shear test: According to GB / T 7124-2008 standard, component A and component B were mixed evenly in a volume ratio of 1:1, and Al3003 and Al3003 were used for bonding to prepare shear specimens. After curing for 7 days in an environment of 25±2℃ and relative humidity of 50±5%, the shear strength test was performed; (4) Body strength and elongation at break test: According to GB / T 1040.1-2018 standard, component A and component B were mixed evenly in a volume ratio of 1:1 to form a 2±0.2 mm sample. After curing for 7 days in an environment of 25±2℃ and relative humidity of 50±5%, a type I tool was used to perform a tensile performance test at a tensile speed of 100 mm / min. (5) Double 85 humidity and heat test: The test was conducted in accordance with GB / T 7124-2008. Component A and component B were mixed evenly in a volume ratio of 1:1, and 3003Al and 3003Al were used for bonding. Shear specimens were prepared and cured in an environment of 25±2℃ and 50±5% relative humidity for 7 days. After that, they were placed in an environment of 85℃ and 85% humidity for 1000 hours. After that, they were taken out and placed in an environment of 25±2℃ and 50±5% relative humidity for 24 hours for shear strength test. The shear strength change rate before and after aging was calculated.
[0057] The test results are shown in Table 7.
[0058] Table 7 Performance test results of the potting glue provided in Examples 1 to 3 and Comparative Examples 1 to 3
[0059] Compared with comparative examples 1 to 3, examples 1 to 3 prepare component A by adjusting specific screened and specified polyester polyols, polyether polyols, castor oil, diluents, lightweight fillers, water scavengers, dispersants, and pigments in specific proportions, and prepare component B by adjusting specific screened and specified polyether polyols, isocyanates, diluents, lightweight fillers, water scavengers, dispersants, and pigments in specific proportions. Component A and component B are mixed in a volume ratio of 1:1. Due to the compound use of microbeads and microspheres, the density of the glue is effectively reduced and the leveling of the glue is effectively improved. The synergistic effect of the soft and hard segment resins between the specific resins solves the contradiction between density and mechanical properties, and has excellent long-term aging resistance. The potting glue has multiple excellent properties at the same time, and the density of the glue after mixing is <0.8 g / cm 3 The viscosity after mixing is less than 4000 mPa·s, the shear strength after curing is greater than 6 MPa, the elongation at break is greater than 200%, and the attenuation of double 85 aging after 1000 h is less than 5%, meeting the performance requirements of low viscosity, low density and high strength of the new potting compound.
[0060] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.
[0061] In summary, compared with the prior art, the technical solution of this application has the following beneficial technical effects: 1. The present invention uses a combination of lightweight filler microbeads and microspheres, as well as the synergistic effect of soft and hard segment resins, which not only effectively reduces the viscosity and density of the glue, but also balances the contradiction between density and mechanical properties, and has multiple excellent properties. 2. The density of the glue provided by the present invention after mixing is less than 0.8g / cm 3The viscosity after mixing is less than 4000mPa·s, the shear strength after curing is greater than 6MPa, the elongation at break is greater than 200%, and the attenuation of double 85 aging after 1000h is less than 5%, meeting the performance requirements of low viscosity, low density and high strength of the new potting glue.
Claims
1. A two-component polyurethane potting adhesive, characterized in that: It includes component A and component B; The A comprises the following raw materials in parts by weight: 0-30 parts of polyester polyol, 0-30 parts of polyether polyol, 0-20 parts of castor oil, 5-20 parts of diluent, 5-25 parts of light filler, 0.1-5 parts of water remover, 0.1-0.5 parts of dispersant, 0.1-0.5 parts of pigment and filler; Described B comprises the following raw materials in parts by weight: 5-20 parts of polyether polyol, 10-60 parts of isocyanate, 10-20 parts of diluent, 5-25 parts of light filler, 0.1-5 parts of water scavenger, 0.1-0.5 parts of dispersant, 0.1-0.5 parts of pigment and filler; Wherein, the lightweight filler includes microbeads and microspheres.
2. The two-component polyurethane potting adhesive according to claim 1, characterized in that: The volume ratio of component A to component B is 1:(0.5~1.5).
3. The two-component polyurethane potting adhesive according to claim 1, characterized in that: In the component A, the hydroxyl value of the polyester polyol is 195 mg KOH / g, and the hydroxyl value of the polyether polyol is 225 mg KOH / g; in the component B, the hydroxyl value of the polyether polyol is 56 mg KOH / g.
4. The two-component polyurethane potting adhesive according to claim 1, characterized in that: The lightweight filler is a mixture of hollow glass microspheres and polystyrene microspheres.
5. The two-component polyurethane potting adhesive according to claim 4, characterized in that: The mass ratio of hollow glass microspheres to polystyrene microspheres is (14~18):(0.4~0.5).
6. The two-component polyurethane potting adhesive according to claim 1, characterized in that: In the component B, the isocyanate includes one or more of 4,4'-methylenebis(cyclohexyl isocyanate), diphenylmethane diisocyanate, isophorone diisocyanate, and polymethylene polyphenyl isocyanate.
7. The two-component polyurethane potting adhesive according to claim 1, characterized in that: In the component A, the diluent is dipropylene glycol; In the component B, the diluent is triisopropylphenyl phosphate.
8. The two-component polyurethane potting adhesive according to claim 1, characterized in that: The dispersant includes a polyurea compound; The dehydrating agent is molecular sieve or oxazolidine.
9. A method for preparing a two-component polyurethane potting adhesive according to any one of claims 1 to 8, characterized in that: The following steps are involved: The polyester polyol, polyether polyol, castor oil, diluent, light filler, water scavenger, dispersant and pigment and filler are mixed after vacuuming to obtain component A; The polyether polyol and isocyanate are mixed and heated to cause a polymerization reaction to obtain a prepolymer, and the prepolymer, isocyanate, diluent, lightweight filler, water scavenger, dispersant and pigment and filler are vacuumed and mixed to obtain component B; Component A and component B are mixed in a volume ratio of 1:1 to obtain a two-component polyurethane potting adhesive.
10. Use of the two-component polyurethane potting adhesive according to any one of claims 1 to 8 in the fields of electronic appliances, new energy vehicles or aerospace.