A storage-stable condensation-type two-component silicone sealant and its preparation method

Abstract

The present invention relates to a storage-stable condensation-type two-component silicone sealant and a preparation method thereof. The sealant comprises component A and component B with a weight ratio of 12:1 to 15:1. In the present invention, a water remover and a treatment agent are added to component B, and all raw materials in component B are pretreated, so that it has good physical and mechanical properties compared with the prior art, and also has the advantages that the break time and the surface drying time after storage are relatively stable, and it is very suitable for application fields with strict requirements for operation time and gluing time, such as electronic appliances, industrial sealing and bonding, etc.

Description

Technical Field

[0001] The present invention belongs to the technical field of sealants, and particularly relates to a condensation-type two-component silicone sealant with stable storage and a preparation method thereof. Background Art

[0002] Silicone sealants have excellent aging resistance, high and low temperature resistance, and good adhesion to most substrates. Therefore, they can be used as sealants, adhesives, potting agents, etc., and are widely used in curtain walls, electronic appliances, automobiles, high-speed rails and other fields. Silicone sealants can be divided into one-component silicone sealants and two-component silicone sealants according to their packaging and use processes. Among them, the two-component silicone sealant is based on a hydroxyl-terminated polydimethylsiloxane as the base polymer, and is compounded with a crosslinking agent, a coupling agent, a catalyst, a filler, etc. Usually in the formulation design, the base polymer and the filler are prepared as component A, and the crosslinking agent, coupling agent, catalyst, etc. are placed in component B. In the actual application process, the components such as the crosslinking agent, coupling agent, and catalyst contained in component B have high activity and will change during storage. The break time and surface drying time will be correspondingly extended with the storage time. In industrial application fields such as sealing and potting, the injection of two-component silicone sealants needs to be coordinated with a pipeline production process. The changes in the break time and surface drying time are obvious, which will directly affect the operation time of the process; at the same time, the break time and surface drying time are significantly extended, and the corresponding initial curing time of the two-component silicone sealant is also significantly extended, which will affect the operation of the next process. Therefore, relatively stable break time and surface drying time are required in some application fields, while the break time and surface drying time of the existing two-component silicone sealants will be correspondingly extended with the storage time, making it difficult to meet some special application requirements. Summary of the Invention

[0003] The purpose of the present invention is to overcome the defects of the above-mentioned prior art and provide a condensation-type two-component silicone sealant with relatively stable break time and surface drying time during storage.

[0004] Another purpose of the present invention is to provide a preparation method of the above-mentioned condensation-type two-component silicone sealant with stable storage.

[0005] The technical solutions adopted to achieve the above invention purposes are as follows:

[0006] A condensation-type two-component silicone sealant with stable storage, characterized in that it comprises component A and component B with a weight ratio of 12∶1 to 15∶1,

[0007] wherein component A comprises raw materials with the following weight ratios:

[0008] 100 parts of α,ω-dihydroxypolydimethylsiloxane,

[0009] 2 to 30 parts of dimethyl silicone oil,

[0010] 60 to 150 parts of inorganic filler;

[0011] Component B described above comprises raw materials in the following weight ratios:

[0012]

[0013] The viscosity of the α,ω-dihydroxypolysiloxane at 25 °C is 5 Pa·s to 80 Pa·s, and the viscosity of the dimethyl silicone oil at 25 °C is 0.1 Pa·s to 20 Pa·s.

[0014] The inorganic filler is at least one of activated calcium carbonate and heavy calcium carbonate.

[0015] The water remover is at least one of vinyltrimethoxysilane and vinyltriethoxysilane.

[0016] The treating agent is hexamethyldisilazane.

[0017] The composite crosslinking agent is at least two of tetraethyl orthosilicate, tetrapropyl orthosilicate, tetrabutyl orthosilicate, polysilicic acid ethyl ester, methyltrimethoxysilane, methyltriethoxysilane, propyltrimethoxysilane, propyltriethoxysilane, dimethyldimethoxysilane, and dimethyldiethoxysilane.

[0018] The coupling agent A is at least one of chloropropyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-β-aminoethyl-γ-aminopropyltrimethoxysilane, N-β-aminoethyl-γ-aminopropyltriethoxysilane, mercaptopropyltrimethylsilane, mercaptopropyltriethylsilane, isocyanate group propyltrimethylsilane, and isocyanate group propyltriethylsilane; the coupling agent B is at least one of glycidyltrimethoxysilane, glycidyltriethoxysilane, epoxycyclohexylethyltrimethoxysilane, and epoxycyclohexylethyltriethoxysilane.

[0019] The catalyst is at least one of dibutyltin diacetate, dibutyltin dilaurate, and dioctyltin dilaurate.

[0020] The preparation method of the above storage-stable condensation-type two-component silicone sealant is characterized by comprising the following steps:

[0021] S1 Preparation of Component A:

[0022] Put α,ω-dihydroxypolydimethylsiloxane, dimethyl silicone oil, and inorganic filler into a kneader or a high-speed disperser, and carry out co-blending and degassing for 30 to 90 minutes under the conditions of a temperature of 50 to 100 °C and a vacuum degree of 0.06 to 0.09 MPa, and obtain Component A after cooling;

[0023] Preparation of Component B of S2

[0024] 1) Preparation of the color paste for Component B: First, mix dimethyl silicone oil and carbon black, stir evenly, then heat up to 90 - 110°C, stir under vacuum conditions for 2 - 3 hours, then cool down to 20°C - 50°C. Under the protection of nitrogen, add the water remover in portions. After the water content does not exceed 500 ppm, continue to stir for 15 - 25 minutes, add the treatment agent, control the temperature at 50 - 70°C, stir for 40 - 60 minutes and then discharge to obtain the color paste.

[0025] 2) Pretreatment of the composite crosslinking agent and catalyst: Reflux the composite crosslinking agent and catalyst at 70 - 110°C under normal pressure for 3 - 8 hours, and then obtain the pretreated crosslinking agent after cooling.

[0026] 3) Pretreatment of the coupling agent: Keep coupling agent A and coupling agent B at 60 - 80°C under normal pressure and nitrogen protection for 8 - 24 hours, and then obtain the pretreated coupling agent after cooling.

[0027] 4) Preparation of Component B: Put the above - obtained color paste, pretreated crosslinking agent and pretreated coupling agent into a high - speed dispersion mixer, and stir evenly at a temperature of 30 - 50°C and a vacuum degree of 0.08 - 0.099 MPa to obtain Component B.

[0028] During use, mix the above - mentioned Component A and Component B evenly according to the ratio and defoam, and then cure at room temperature.

[0029] In the present invention, by the method of pretreating the color paste of Component B to remove water and hydroxyl groups, the adverse effects of moisture and active groups in the color paste on storage stability are minimized as much as possible; by adopting the methods of pretreating the crosslinking agent and the coupling agent, the possible mutual reactions are allowed to occur first during the pretreatment process to form a more stable mixture, and then Component B is prepared, so that the obtained Component B has more stable characteristics.

[0030] Experiments prove that the condensation - type two - component silicone sealant of the present invention has the following technical advantages:

[0031] 1. The break - off time and surface - drying time are relatively stable after storage; in industrial application fields such as sealing and potting, especially for the injection of two - component silicone sealant, it needs to cooperate with the assembly - line production process. The available operation time range for each process is relatively small. The stability of the break - off time and surface - drying time is very suitable for application fields with strict requirements for operation time and application time in the production process.

[0032] 2. Adopting a two - component neutral curing system, it has a fast curing speed and good mechanical properties.

[0033] In summary, compared with the existing condensation-type two-component silicone sealant, the condensation-type two-component silicone sealant of the present invention also has good physical and mechanical properties, and also has the advantages of relatively stable break time and surface drying time after storage, and is very suitable for application fields such as electronic appliances and industrial sealing and bonding where strict requirements are imposed on the operation time and glue application time. Detailed implementation mode

[0034] The technical solutions of the present invention will be described in detail below through specific embodiments, but the scope of the present invention is not limited. The following described embodiments are only a part of the embodiments of the present invention, rather than all embodiments. All other similar embodiments made by those skilled in the art without creative efforts fall within the scope of protection of the present invention.

[0035] Example 1

[0036] Preparation of Component A:

[0037] 100 parts by weight of α,ω-dihydroxypolydimethylsiloxane with a viscosity of 10 Pa·s at 25°C, 10 parts by weight of dimethyl silicone oil with a viscosity of 0.1 Pa·s, and 100 parts by weight of nano-active calcium carbonate are added to a kneading machine. At a temperature of 70°C and a vacuum degree of 0.08 MPa, they are blended and degassed for 30 to 90 minutes, and Component A is obtained after cooling.

[0038] Preparation of Component B:

[0039] 1) Preparation of the color paste for Component B: In a high-speed dispersion mixer, 100 parts by weight of dimethyl silicone oil with a viscosity of 1 Pa·s and 25 parts by weight of carbon black are mixed and stirred evenly. After heating to about 110°C, they are stirred under vacuum conditions for 3 hours, and then cooled to 50°C. Under the protection of nitrogen, 1 part by weight of vinyltrimethoxysilane is added in 2 portions. The water content of the sample is measured by the Karl Fischer method. After the measured water content is 480 ppm, it is stirred for another 20 min. 0.8 part of hexamethyldisilazane is added, the rotation speed is adjusted appropriately, the temperature is controlled at 50°C, and after stirring for 60 min, the color paste is discharged.

[0040] 2) Pretreatment of the composite cross-linking agent and catalyst: 25 parts by weight of tetraethyl orthosilicate, 5 parts by weight of methyltrimethoxysilane, and 1.2 parts by weight of dibutyltin dilaurate are added to a reaction kettle with a condensation reflux device. Under normal pressure, it is heated to 105°C, refluxed for 6 hours, and then the heating is stopped and cooled in a closed state to obtain the pretreated cross-linking agent.

[0041] 3) Pretreatment of the coupling agent: 20 parts by weight of γ-aminopropyltriethoxysilane and 5 parts by weight of glycidyltrimethoxysilane are added to a reaction kettle. The material temperature is controlled at 75°C. Under normal pressure and under the protection of nitrogen, the temperature is maintained for 24 hours and then cooled to obtain the pretreated coupling agent.

[0042] 4) Preparation of Component B: Put the color paste, pretreated crosslinking agent, and pretreated crosslinking agent from the above steps 1), 2), and 3) into a high-speed dispersion mixer, control the temperature at 45°C, the vacuum degree at 0.095 MPa, and stir evenly to obtain Component B.

[0043] Sealant preparation:

[0044] During use, mix the above Component A and Component B evenly by weight ratio of 15:1 and degas, and cure at room temperature.

[0045] Example 2

[0046] Preparation of Component A:

[0047] Put 100 parts by weight of α,ω-dihydroxy polydimethylsiloxane with a viscosity of 8 Pa·s at 25°C, 2 parts by weight of dimethyl silicone oil with a viscosity of 0.1 Pa·s, and 85 parts by weight of nano-active calcium carbonate into a kneader or high-speed disperser. Under the conditions of a temperature of 50°C and a vacuum degree of 0.065 MPa, carry out blending and degassing for 90 minutes, and obtain Component A after cooling.

[0048] Preparation of Component B:

[0049] 1) Preparation of the color paste for Component B: In a high-speed dispersion mixer, mix 100 parts by weight of dimethyl silicone oil with a viscosity of 8 Pa·s and 15 parts by weight of carbon black evenly, heat to about 95°C, stir under vacuum conditions for 3 hours, cool to 45°C, and add 1.5 parts by weight of vinyltriethoxysilane in 2 portions under nitrogen protection. Take a sample and test the water content by the Karl Fischer method, and the measured water content is 425 ppm. Then stir for 20 min, add 0.5 part of hexamethyldisilazane, adjust the appropriate rotation speed, control the temperature at 70°C, and discharge the material after stirring for 40 min to obtain the color paste.

[0050] 2) Pretreatment of the composite crosslinking agent and catalyst: Put 25 parts by weight of propyl orthosilicate, 2 parts by weight of methyltrimethoxysilane, and 1.0 part by weight of dibutyltin dilaurate into a reaction kettle with a condensation reflux device. Under normal pressure, heat to 100°C, reflux for 8 hours, then stop heating and cool it in a closed state to obtain the pretreated crosslinking agent.

[0051] 3) Pretreatment of the coupling agent: Put 20 parts by weight of N-β-aminoethyl-γ-aminopropyltrimethoxysilane and 10 parts by weight of glycidyltrimethoxysilane into a reaction kettle, control the material temperature at 80°C, keep the temperature at 9 hours under nitrogen protection at normal pressure, and then cool to obtain the pretreated coupling agent.

[0052] 4) Preparation of Component B: Put the color paste, pretreated crosslinking agent, and pretreated crosslinking agent in the above steps 1), 2), and 3) into a high-speed dispersion mixer, control the temperature at 35°C, the vacuum degree at 0.092 MPa, and stir evenly to obtain Component B.

[0053] Sealant preparation:

[0054] During use, mix the above Component A and Component B evenly by weight ratio of 13:1 and degas, and cure at room temperature.

[0055] Example 3

[0056] Preparation of Component A:

[0057] Add 100 parts by weight of α,ω-dihydroxypolydimethylsiloxane with a viscosity of 15 Pa·s at 25°C, 25 parts by weight of dimethyl silicone oil with a viscosity of 1 Pa·s, 100 parts by weight of nano calcium carbonate, and 30 parts of heavy calcium carbonate into a kneader or high-speed disperser. Under the conditions of a temperature of 80°C and a vacuum degree of 0.07 MPa, blend and degas for 60 minutes, and cool to obtain Component A.

[0058] Preparation of Component B:

[0059] 1) Preparation of the color paste for Component B: In a high-speed dispersion mixer, mix 100 parts by weight of dimethyl silicone oil with a viscosity of 5 Pa·s and 25 parts by weight of carbon black evenly, heat to about 100°C, stir under vacuum conditions for 3 hours, cool to 40°C, and add 2 parts by weight of vinyltriethoxysilane in 2 portions under nitrogen protection. Take a sample and measure the water content by the Karl Fischer method. After measuring the water content of 395 ppm, stir for another 20 minutes, add 0.4 part of hexamethyldisilazane, adjust the appropriate rotation speed, control the temperature at 65°C, and discharge after stirring for 55 minutes to obtain the color paste.

[0060] 2) Pretreatment of the composite crosslinking agent and catalyst: Put 10 parts by weight of tetraethyl orthosilicate, 10 parts by weight of propyl orthosilicate, and 1.2 parts by weight of dioctyltin dilaurate into a reaction kettle with a condensation reflux device. Under normal pressure, heat to 95°C, reflux for 5 hours, then stop heating and cool it in a closed state to obtain the pretreated crosslinking agent.

[0061] 3) Pretreatment of the coupling agent: Add 15 parts by weight of N-β-aminoethyl-γ-aminopropyltrimethoxysilane and 10 parts by weight of epoxycyclohexylethyltriethoxysilane to the reaction kettle, control the material temperature at 70°C, keep the temperature for 18 hours under normal pressure and nitrogen protection, and then cool to obtain the pretreated coupling agent.

[0062] 4) Preparation of Component B: Put the color paste, pretreated crosslinking agent, and pretreated crosslinking agent in each of the above steps 1), 2), and 3) into a high-speed dispersion mixer. Under the conditions of a temperature controlled at 40°C and a vacuum degree of 0.088 MPa, stir evenly to obtain Component B.

[0063] Sealant preparation:

[0064] During use, mix the above Component A and Component B evenly by weight ratio of 12:1 and degas, and cure at room temperature.

[0065] Example 4

[0066] Preparation of Component A:

[0067] Add 100 parts by weight of α,ω-dihydroxypolydimethylsiloxane with a viscosity of 20 Pa·s at 25°C, 30 parts by weight of dimethyl silicone oil with a viscosity of 4 Pa·s, 90 parts by weight of nano calcium carbonate, and 60 parts of heavy calcium carbonate into a kneader or high-speed disperser. At a temperature of 55°C and a vacuum degree of 0.07 MPa, blend and degas for 40 minutes, and then cool to obtain Component A.

[0068] Preparation of Component B:

[0069] 1) Preparation of the color paste for Component B: In a high-speed dispersion mixer, mix 100 parts by weight of dimethyl silicone oil with a viscosity of 15 Pa·s and 15 parts by weight of carbon black evenly, heat to about 110°C, stir for 3 hours under vacuum conditions, cool to 50°C, and add 1.6 parts of vinyltrimethoxysilane in two portions under nitrogen protection. Take a sample and test the water content by the Karl Fischer method. After measuring the water content of 405 ppm, stir for another 20 minutes, add 1.2 parts of hexamethyldisilazane, adjust the appropriate rotation speed, control the temperature at 60°C, stir for 60 minutes and then discharge to obtain the color paste.

[0070] 2) Pretreatment of the composite crosslinking agent and catalyst: Add 15 parts by weight of tetraethyl orthosilicate, 5 parts by weight of dimethyldiethoxysilane, and 1.5 parts by weight of dioctyltin dilaurate into a reaction kettle with a condensing reflux device. Under normal pressure, heat to 110°C, reflux for 5 hours, then stop heating and cool it in a closed state to obtain the pretreated crosslinking agent.

[0071] 3) Pretreatment of the coupling agent: Add 20 parts by weight of N-β-aminoethyl-γ-aminopropyltrimethoxysilane and 5 parts of epoxycyclohexylethyltrimethoxysilane into a reaction kettle, control the material temperature at 60°C, keep the temperature for 12 hours under normal pressure and nitrogen protection, and then cool to obtain the pretreated coupling agent.

[0072] 4) Preparation of Component B: Put the color paste, pretreated crosslinking agent, and pretreated crosslinking agent in the high-speed dispersion mixer in the above steps 1), 2), and 3), control the temperature at 45°C, the vacuum degree at 0.095 MPa, and stir evenly to obtain Component B.

[0073] Sealant preparation:

[0074] During use, mix the above Component A and Component B evenly by weight ratio of 15:1 and defoam, and cure at room temperature.

[0075] Comparative Example 1

[0076] Preparation of Component A:

[0077] Exactly the same as Example 1.

[0078] Preparation of Component B:

[0079] Only the preparation of the color paste for Component B is different (there is no water remover and treatment agent in the raw materials), and the other steps are exactly the same as Example 1.

[0080] Preparation of the color paste for Component B: In the high-speed dispersion mixer, mix 100 parts by weight of dimethyl silicone oil with a viscosity of 1 Pa·s and 25 parts by weight of carbon black evenly, heat up to about 110°C, stir for 3 hours under vacuum conditions, cool down to below 50°C, and discharge to obtain the color paste for Component B.

[0081] When using the two-component silicone sealant, it is exactly the same as Example 1.

[0082] Comparative Example 2

[0083] Preparation of Component A:

[0084] Exactly the same as Example 1.

[0085] Preparation of Component B:

[0086] 1) The preparation of the color paste for Component B is different from that in Example 1 (there is no water remover and treatment agent in the raw materials), specifically: In the high-speed dispersion mixer, mix 100 parts by weight of dimethyl silicone oil with a viscosity of 1 Pa·s and 25 parts by weight of carbon black evenly, heat up to about 110°C, stir for 3 hours under vacuum conditions, cool down to below 50°C, and discharge to obtain the color paste for Component B.

[0087] 2) The composite crosslinking agent and catalyst are not pretreated, and the rest is the same as Example 1.

[0088] 3) The coupling agent is pretreated, and the treatment process is the same as Example 1.

[0089] 4) Preparation of Component B: Prepare the components in the above steps 1), 2), and 3) in the same way as in Example 1.

[0090] When using the two-component silicone sealant, it is exactly the same as in Example 1.

[0091] Comparative Example 3

[0092] Preparation of Component A:

[0093] It is exactly the same as in Example 1.

[0094] Preparation of Component B:

[0095] 1) The preparation of the color paste for Component B is different from that in Example 1 (there is no water remover and treatment agent in the raw materials). Specifically, in a high-speed dispersion mixer, 100 parts by weight of dimethyl silicone oil with a viscosity of 1 Pa·s and 25 parts by weight of carbon black are mixed evenly. After heating to about 110 °C, it is stirred under vacuum conditions for 3 hours, cooled to below 50 °C, and the color paste of Component B is obtained.

[0096] 2) The composite cross-linking agent and catalyst are not pretreated, and the rest is the same as in Example 1.

[0097] 3) The coupling agent is not pretreated, and the rest is the same as in Example 1.

[0098] 4) Preparation of Component B: The components in each step of 1), 2), and 3) above are used to prepare Component B in the same way as in Example 1.

[0099] When using the two-component silicone sealant, it is exactly the same as in Example 1.

[0100] In the above examples and comparative examples, both Component A and Component B are stored under standard conditions (23 °C, 50% RH). When the samples are stored for 7 days and 6 months, the break time, surface drying time, and tensile strength are tested under standard conditions (23 °C, 50% RH).

[0101] Among them, the break time test is carried out according to the provisions in Appendix D of the national standard GB 16776-2005.

[0102] Among them, the surface drying time test is carried out according to the national standard GB / T 13477.5-2002.

[0103] Among them, for the tensile strength test, after the test specimens are cured for 14 days under standard conditions (23 °C, 50% RH), the tensile strength test is carried out according to Type 1 test specimens in GB / TT528-2009.

[0104] The test results can be seen in Table 1, as can be seen from Table 1.

[0105] Table 1:

[0106]

[0107] As can be seen from Table 1, after the color paste of component B, the composite crosslinking agent, the catalyst, and the coupling agent were respectively pretreated in Examples 1 to 4, the breaking time and the surface drying time after 6 months of storage showed little change compared with those after 7 days of storage; while in Comparative Examples 1 to 2, only one or two parameters of the color paste, the composite crosslinking agent, the catalyst, and the coupling agent in component B were pretreated, and in Comparative Example 3, there was no pretreatment. The breaking time and the surface drying time after 6 months of storage in Comparative Examples 1 to 3 changed significantly compared with those after 7 days of storage. This fully shows that by pretreating the color paste, the crosslinking agent, and the coupling agent and then preparing component B, component B with more stable characteristics can be obtained in the present invention.

Claims

1. A storage-stable condensation-type two-component silicone sealant, characterized in that it comprises component A and component B with a weight ratio of 12:1 to 15:1, wherein component A comprises raw materials with the following weight ratios: 100 parts of α,ω-dihydroxypolydimethylsiloxane, 2 to 30 parts of dimethyl silicone oil, and 60 to 150 parts of inorganic filler; component B comprises raw materials with the following weight ratios: 100 parts of dimethyl silicone oil, 5 to 30 parts of carbon black, 0.2 to 2 parts of water scavenger, 0.2 to 2 parts of treatment agent, 5 to 30 parts of composite cross-linking agent, 5 to 20 parts of coupling agent A, 5 to 20 parts of coupling agent B, and 0.1 to 1.5 parts of catalyst; The preparation method of the storage-stable condensation-type two-component silicone sealant comprises the following steps: Preparation of component A: Put α,ω-dihydroxypolydimethylsiloxane, dimethyl silicone oil and inorganic filler into a kneader or high-speed disperser, and carry out co-blending and degassing for 30 to 90 minutes under the conditions of a temperature of 50 to 100 °C and a vacuum degree of 0.06 to 0.09 MPa, and obtain component A after cooling; Preparation of component B: (1) Preparation of the color paste for component B: First, mix dimethyl silicone oil and carbon black, stir evenly, then heat up to 90 to 110 °C, stir for 2 to 3 hours under vacuum conditions, then cool down to 20 °C to 50 °C, and under the state of nitrogen protection, add the water scavenger in portions. After the water content does not exceed 500 ppm, continue to stir for 15 to 25 min, add the treatment agent, control the temperature at 50 to 70 °C, and discharge the material after stirring for 40 to 60 min to obtain the color paste; (2) Pretreatment of the composite cross-linking agent and catalyst: Carry out reflux treatment on the composite cross-linking agent and catalyst at a temperature of 70 to 110 °C under normal pressure for 3 to 8 hours, and obtain the pretreated cross-linking agent after cooling; (3) Pretreatment of the coupling agent: Keep coupling agent A and coupling agent B at a temperature of 60 to 80 °C under normal pressure, nitrogen protection for 8 to 24 hours, and obtain the pretreated coupling agent after cooling; (4) Preparation of component B: Put the obtained color paste, pretreated cross-linking agent and pretreated coupling agent into a high-speed dispersion mixer, and stir evenly under the conditions of a temperature of 30 to 50 °C and a vacuum degree of 0.08 to 0.099 MPa to obtain component B; The treatment agent is hexamethyldisilazane.

2. The storage-stable condensation-type two-component silicone sealant according to claim 1, characterized in that the viscosity of the α,ω-dihydroxypolydimethylsiloxane at 25 °C is 5 Pa·s to 80 Pa·s, and the viscosity of the dimethyl silicone oil at 25 °C is 0.1 Pa·s to 20 Pa·s.

3. The storage-stable condensation-type two-component silicone sealant according to claim 1, characterized in that the inorganic filler is at least one of active calcium carbonate and heavy calcium carbonate.

4. The storage-stable condensation-type two-component silicone sealant as claimed in claim 1, characterized in that the water scavenger is at least one of vinyltrimethoxysilane and vinyltriethoxysilane.

5. The storage-stable condensation-type two-component silicone sealant as claimed in claim 1, characterized in that The composite crosslinking agent is at least two of tetraethyl orthosilicate, tetrapropyl orthosilicate, tetrabutyl orthosilicate, ethyl polysilicate, methyltrimethoxysilane, methyltriethoxysilane, propyltrimethoxysilane, propyltriethoxysilane, dimethyldimethoxysilane, and dimethyldiethoxysilane.

6. The storage-stable condensation-type two-component silicone sealant according to claim 1, characterized in that the coupling agent A is at least one of chloropropyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, and N-(β-aminoethyl)-γ-aminopropyltriethoxysilane; the coupling agent B is at least one of glycidyltrimethoxysilane, glycidyltriethoxysilane, epoxycyclohexylethyltrimethoxysilane, and epoxycyclohexylethyltriethoxysilane.

7. The storage-stable condensation-type two-component silicone sealant according to claim 1, characterized in that the catalyst is at least one of dibutyltin diacetate, dibutyltin dilaurate, and dioctyltin dilaurate.

8. A method for preparing the storage-stable condensation-type two-component silicone sealant according to any one of claims 1-7, characterized in that it includes the following steps: S1 Preparation of component A: Put α,ω-dihydroxypolydimethylsiloxane, dimethyl silicone oil, and inorganic filler into a kneader or high-speed disperser, and carry out co-blending and degassing for 30-90 minutes under the conditions of a temperature of 50-100 °C and a vacuum degree of 0.06-0.09 MPa. After cooling, component A is obtained; S2 Preparation of component B: 1) Preparation of the color paste for component B: First, mix dimethyl silicone oil and carbon black, stir evenly, then heat up to 90-110 °C, stir for 2-3 hours under vacuum conditions, then cool down to 20 °C - 50 °C, and under the state of nitrogen protection, add the water remover in portions. After the water content does not exceed 500 ppm, continue to stir for 15-25 min, add the treatment agent, control the temperature at 50-70 °C, and stir for 40-60 min before discharging to obtain the color paste; 2) Pretreatment of the composite crosslinking agent and the catalyst: Carry out reflux treatment on the composite crosslinking agent and the catalyst at a temperature of 70-110 °C under normal pressure for 3-8 hours, and after cooling, the pretreated crosslinking agent is obtained; 3) Pretreatment of the coupling agent: Keep the coupling agent A and the coupling agent B at a temperature of 60-80 °C under normal pressure, nitrogen protection for 8-24 hours, and after cooling, the pretreated coupling agent is obtained; 4) Preparation of component B: Put the above-mentioned obtained color paste, pretreated crosslinking agent, and pretreated coupling agent into a high-speed dispersion mixer, and stir evenly under the conditions of a temperature of 30-50 °C and a vacuum degree of 0.08-0.099 MPa to obtain component B; During use, mix the above-mentioned component A and component B evenly and defoam, and cure at room temperature.

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