Modified silane coupling agent, modified heavy calcium carbonate, dealcoholized silicone sealant and preparation method thereof

Abstract

The invention discloses a modified silane coupling agent, modified heavy calcium carbonate, a dealcoholized silicone sealant and a preparation method thereof. The modified silane coupling agent is obtained by reacting N-[3-(trimethoxysilyl) propyl] aniline and 12-amino dodecanoic acid under the action of a catalyst. A modifier compounded by the modified silane coupling agent and a nonionic surfactant is used for modifying heavy calcium carbonate to obtain modified heavy calcium carbonate, and the modified heavy calcium carbonate can replace part of nano calcium carbonate and is added into a dealcoholized silicone sealant as a filler. According to the present invention, the heat resistance, the extrudability, the adhesion property and the mechanical property of the dealcoholized silicone sealant can be improved, the production cost can be reduced, and the dealcoholized silicone sealant releases alcohol small molecules during the curing process, has characteristics of small odor, no corrosion on metal, concrete, glass and other building base materials, and has characteristics of environmental protection.

Description

Technical Field

[0001] This invention belongs to the field of sealant technology, specifically relating to a modified silane coupling agent, modified heavy calcium carbonate, a dealcoholized silicone sealant, and their preparation methods. Background Technology

[0002] De-alcoholized silicone sealants are liquid silicone rubbers that are mixed with base adhesives, fillers, crosslinking agents, catalysts, coupling agents, etc., and can be stored for a long time. They release small alcohol molecules during curing. Fillers are mainly divided into heavy calcium carbonate and light calcium carbonate, which play a role in the sealant system by reinforcing, reducing costs, and providing special properties. With the maturity of sealant technology, the industry generally uses a mixture of heavy and light calcium carbonate to achieve better performance while also reducing costs. Although a higher proportion of heavy calcium carbonate in the filler leads to lower costs, an excessively high proportion of heavy calcium carbonate can degrade the mechanical properties, adhesion, application performance, and shelf life of the de-alcoholized silicone sealant. Conversely, an excessively high proportion of light calcium carbonate can lead to poor appearance and a thicker sealant during production. Therefore, maximizing the proportion of heavy calcium carbonate in the filler while maintaining good sealant performance and production efficiency has become a key challenge.

[0003] To achieve these goals, the industry has proposed many solutions. For example, CN119614142A proposes using stearic acid and aluminate ester nonionic modifiers to obtain modified heavy calcium carbonate, which can then partially replace the light calcium carbonate in the formulation. However, this modified heavy calcium carbonate uses a large number of nonionic surface modifiers, which may affect the weather resistance of the silicone sealant. Furthermore, the formulation uses volatile plasticizers, which are detrimental to the performance retention of the silicone sealant after curing. CN119684819A proposes using castor oil derivative comb-like superdispersants to modify heavy calcium carbonate, obtaining a silicone sealant with good flowability and dispersibility. However, because castor oil derivatives are used as modifiers, they have too many hydroxyl groups on their surface, which is detrimental to the shelf life performance of the silicone sealant. Summary of the Invention

[0004] The purpose of this invention is to provide a modified silane coupling agent that can be combined with a nonionic surfactant to modify heavy calcium carbonate. The resulting modified heavy calcium carbonate can improve the heat resistance, extrusion properties, adhesion properties, and mechanical properties of dealcoholized silicone sealants.

[0005] The following technical solutions are used to achieve the above objectives.

[0006] The first aspect of this invention provides a modified silane coupling agent having the following structural formula:

[0007] .

[0008] A second aspect of the present invention provides a method for preparing the modified silane coupling agent as described above, comprising the following steps:

[0009] Under the protection of nitrogen or an inert gas, 3-(phenylamino)propyltrimethoxysilane and 12-aminododecanoic acid react in the presence of a catalyst to obtain the modified siloxane.

[0010] The structure of 3-(phenylamino)propyltrimethoxysilane is as follows:

[0011] ;

[0012] The structure of 12-aminododecanoic acid is as follows:

[0013] .

[0014] In some embodiments, the reaction temperature is 20°C to 30°C, and the reaction time is 2 hours to 6 hours; and / or,

[0015] The catalyst is at least one selected from 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride, 1-hydroxybenzotriazole, or N,N'-dicyclohexylcarbodiimide; and / or

[0016] The molar ratio of 3-(phenylamino)propyltrimethoxysilane to 12-aminododecanoic acid is 2-5:1, preferably 2-3:1; and / or,

[0017] The reaction is carried out in a solvent, preferably tetrahydrofuran; and / or,

[0018] The molar ratio of the catalyst to the 12-aminododecanoic acid is 1:1 to 2, preferably 1:1.1 to 1.3.

[0019] A third aspect of the present invention provides a modified heavy calcium carbonate, wherein the modified heavy calcium carbonate is obtained by modifying heavy calcium carbonate with a modifier;

[0020] The modifiers include nonionic surfactants and modified silane coupling agents as described above.

[0021] In some embodiments, the nonionic surfactant is at least one selected from lauric acid, palmitic acid, and fatty acids, preferably lauric acid; and / or,

[0022] The mass ratio of the modified silane coupling agent to the nonionic surfactant is 1.5~4:1, preferably 2~4:1, more preferably 3~4:1, and even more preferably 3.8~4:1; and / or,

[0023] The mass ratio of the heavy calcium carbonate to the modifier is 100:1~5; preferably 100:1.5~2.

[0024] The fourth aspect of the present invention provides the application of the modified heavy calcium carbonate as described above as a filler in a dealcoholized silicone sealant.

[0025] The fifth aspect of this invention provides a method for preparing the modified heavy calcium carbonate as described above, comprising the following steps:

[0026] Heavy calcium carbonate water is added to a reaction vessel and heated to 70℃~80℃, and stirred to obtain a calcium carbonate suspension;

[0027] The obtained calcium carbonate suspension was mixed with a modifier and stirred at 500 rpm to 70 rpm for 60 min to 70 min at 65℃ to 70℃. The mixture was then dried and ground to obtain the modified heavy calcium carbonate.

[0028] The sixth aspect of the present invention provides a de-alcoholized silicone sealant, wherein the raw materials for preparing the de-alcoholized silicone sealant include fillers, and the fillers contain modified heavy calcium carbonate as described above.

[0029] In some embodiments, the product is prepared by weight from the following components:

[0030] 100 parts of α,ω-dihydroxypolydimethylsiloxane

[0031] 5-10 parts of dimethyl silicone oil

[0032] 150-250 parts of filler

[0033] 2-6 parts of crosslinking agent

[0034] 0-2 parts of silane coupling agent

[0035] 2-6 parts catalyst;

[0036] The filler includes light calcium carbonate and the modified heavy calcium carbonate;

[0037] Preferably, the mass ratio of light calcium carbonate to modified heavy calcium carbonate is 1:0.5~3, more preferably 1:0.5~1.5, and even more preferably 1:0.9~1.1; and / or,

[0038] The viscosity of the α,ω-dihydroxypolydimethylsiloxane at 25°C is 5000 mPa·s to 150000 mPa·s; and / or,

[0039] The dimethyl silicone oil has a viscosity of 100 mPa·s to 10000 mPa·s at 25°C; and / or,

[0040] The modified heavy calcium carbonate has a particle size of 4 μm to 10 μm; and / or,

[0041] The light calcium carbonate has a particle size of 50 nm to 100 nm; and / or,

[0042] The crosslinking agent is methyltrimethoxysilane; and / or,

[0043] The silane coupling agent is at least one selected from γ-aminopropyltriethoxysilane, N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane, glycidyltriethoxysilane, and glycidyltrimethoxysilane; and / or

[0044] The catalyst is diisopropyl bis(ethyl acetoacetate) titanate.

[0045] In some embodiments, the product is prepared by weight from the following components:

[0046] 100 parts of α,ω-dihydroxypolydimethylsiloxane

[0047] 5-10 parts of dimethyl silicone oil

[0048] 180-220 parts of filler

[0049] 3-5 parts of crosslinking agent

[0050] 1-2 parts of silane coupling agent

[0051] 3-5 parts catalyst.

[0052] A seventh aspect of the present invention provides a method for preparing the alcohol-free silicone sealant as described above, comprising the following steps:

[0053] α,ω-dihydroxypolydimethylsiloxane, dimethyl silicone oil and filler are added to a kneader, the temperature is controlled at 60~160 ℃, the vacuum degree is -0.06 MPa~-0.09 MPa, dehydration and blending is carried out for 45min~300min, and then cooled to obtain the base material;

[0054] The base material is added to a planetary mixer and dispersed and stirred for 5 to 10 minutes, with a vacuum degree of -0.06 MPa to -0.09 MPa and a rotation speed of 600 rpm to 720 rpm. Then, the crosslinking agent, coupling agent and catalyst are added to the planetary mixer and stirred continuously for 10 to 45 minutes, with the vacuum degree controlled at -0.045 MPa to -0.09 MPa and the rotation speed at 600 to 720 rpm, thus obtaining the de-alcoholized silicone sealant.

[0055] In this invention, a modified silane coupling agent is prepared by reacting 3-(phenylamino)propyltrimethoxysilane and 12-aminododecanoic acid. This modified silane coupling agent is then combined with a nonionic surfactant to modify heavy calcium carbonate, resulting in modified heavy calcium carbonate. This modified heavy calcium carbonate can replace a portion of nano-calcium carbonate and be added as a filler to dealcoholized silicone sealant. This improves the heat resistance, extrusion properties, adhesion, and mechanical properties of the dealcoholized silicone sealant, reduces production costs, and releases small alcohol molecules during curing, resulting in a low odor and no corrosion to building substrates such as metals, concrete, and glass, thus exhibiting environmental friendliness. Attached Figure Description

[0056] Figure 1 This is a characteristic spectrum of the modified silane coupling agent of Example 1 of the present invention. Detailed Implementation

[0057] To facilitate understanding of the present invention, a more complete description will be provided below. The present invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the present invention.

[0058] Unless otherwise specified, experimental methods in the following examples are generally performed under standard conditions or as recommended by the manufacturer. All commonly used chemical reagents used in the examples are commercially available products.

[0059] Unless otherwise defined, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. The term "and / or" as used in this invention includes any and all combinations of one or more of the associated listed items.

[0060] Example 1

[0061] The preparation method of the dealcoholized silicone sealant provided in this embodiment includes the following steps by weight:

[0062] 1) Synthesis of modified silane coupling agents:

[0063] Under nitrogen protection, 3-(phenylamino)propyltrimethoxysilane, 12-aminododecanoic acid, and 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride were added to tetrahydrofuran and reacted for 3 h at a reaction temperature of 25 °C to obtain the reactant. The reactant was extracted with ethyl acetate, separated by chromatography, and then dried and concentrated to obtain the modified silane coupling agent.

[0064] The molar ratio of 3-(phenylamino)propyltrimethoxysilane to 12-aminododecanoic acid is 2:1, and the molar ratio of 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride to 12-aminododecanoic acid is 1:1.2.

[0065] The structural formula of the modified silane coupling agent is shown below, and its characteristic spectrum is as follows. Figure 1 As shown:

[0066]

[0067] 2) Preparation of modified heavy calcium carbonate:

[0068] 1000g of heavy calcium carbonate with an average particle size of 10μm and 300g of water were added to a reaction vessel, heated to 75℃ and stirred at a constant speed to obtain a calcium carbonate suspension.

[0069] 20g of modifier was added to the reactor, the temperature was controlled at 68℃, and the mixture was stirred at 600rpm for 65 minutes. The modifier was a mixture of modified silane coupling agent and lauric acid in a mass ratio of 1.5:1.

[0070] After the reaction was completed, the slurry was filtered, dried and ground to obtain modified heavy calcium carbonate with an average particle size of 6 μm.

[0071] 3) Preparation of alcohol-free silicone sealant:

[0072] 100 parts of α,ω-dihydroxypolydimethylsiloxane (WACK, FD50, Germany) with a viscosity of 50,000 mPa·s at 25℃, 70 parts of modified heavy calcium carbonate, 130 parts of light calcium carbonate (Guangxi Huana New Material Co., Ltd., CCS-23, average particle size 88.75nm), and 5 parts of dimethyl silicone oil (WACK, AK500, Germany) with a viscosity of 500 mPa·s at 25℃ were added to a kneader and dehydrated and blended at 120℃ and a vacuum of -0.09 MPa for 120 min. The resulting base material was then cooled for later use.

[0073] The above-obtained base material was added to a planetary mixer, and then 4 parts of methyltrimethoxysilane, 2 parts of γ-aminopropyltrimethoxysilane, and 4 parts of diisopropyl bis(ethyl acetoacetate) titanate catalyst were added. The mixture was reacted for 45 minutes under a vacuum of -0.09 MPa and a rotation speed of 600 rpm to obtain a dealcoholized silicone sealant.

[0074] Example 2

[0075] The preparation method of the dealcoholized silicone sealant provided in this embodiment includes the following steps by weight:

[0076] 1) Synthesis of modified silane coupling agents:

[0077] The preparation method is the same as in Example 1.

[0078] 2) Preparation of modified heavy calcium carbonate:

[0079] The preparation method differs from that in Example 1 in that the modifier is a mixture of modified silane coupling agent and lauric acid in a ratio of 2.1:1. Everything else is the same as in Example 1.

[0080] 3) Preparation of alcohol-free silicone sealant:

[0081] The preparation method is the same as in Example 1.

[0082] Example 3

[0083] The preparation method of the dealcoholized silicone sealant provided in this embodiment includes the following steps by weight:

[0084] 1) Synthesis of modified silane coupling agents:

[0085] The preparation method is the same as in Example 1.

[0086] 2) Preparation of modified heavy calcium carbonate:

[0087] The preparation method differs from that in Example 1 in that the modifier is a mixture of modified silane coupling agent and lauric acid in a ratio of 2.3:1. Everything else is the same as in Example 1.

[0088] 3) Preparation of alcohol-free silicone sealant:

[0089] The preparation method is the same as in Example 1.

[0090] Example 4

[0091] The preparation method of the dealcoholized silicone sealant provided in this embodiment includes the following steps by weight:

[0092] 1) Synthesis of modified silane coupling agents:

[0093] The preparation method is the same as in Example 1.

[0094] 2) Preparation of modified heavy calcium carbonate:

[0095] The preparation method differs from that in Example 1 in that the modifier is a mixture of modified silane coupling agent and lauric acid in a 3:1 ratio. Everything else is the same as in Example 1.

[0096] 3) Preparation of alcohol-free silicone sealant:

[0097] The preparation method is the same as in Example 1.

[0098] Example 5

[0099] The preparation method of the dealcoholized silicone sealant provided in this embodiment includes the following steps by weight:

[0100] 1) Synthesis of modified silane coupling agents:

[0101] The preparation method is the same as in Example 1.

[0102] 2) Preparation of modified heavy calcium carbonate:

[0103] The preparation method differs from that in Example 1 in that the modifier is a mixture of modified silane coupling agent and lauric acid in a 4:1 ratio. Everything else is the same as in Example 1.

[0104] 3) Preparation of alcohol-free silicone sealant:

[0105] The preparation method differs from that in Example 1 in that it uses 100 parts of modified heavy calcium carbonate and 100 parts of light calcium carbonate. Everything else is the same as in Example 1.

[0106] Comparative Example 1

[0107] The preparation method of the dealcoholized silicone sealant provided in this comparative example differs from that in Example 1 in that:

[0108] In the preparation method of modified heavy calcium carbonate, only a modified silane coupling agent is used to modify the heavy calcium carbonate. The amount of other raw materials and the preparation process are the same as in Example 1.

[0109] Comparative Example 2

[0110] The preparation method of the dealcoholized silicone sealant provided in this comparative example differs from that in Example 1 in that:

[0111] In the preparation method of modified heavy calcium carbonate, only lauric acid is used to modify the heavy calcium carbonate. The amount of other raw materials and the preparation process are the same as in Example 1.

[0112] Comparative Example 3:

[0113] The preparation method of the dealcoholized silicone sealant provided in this comparative example differs from that in Example 1 in that:

[0114] In the preparation method of modified heavy calcium carbonate, the mixing ratio of modified silane coupling agent and lauric acid is 1:1. The amounts of other raw materials and the preparation process are the same as in Example 1.

[0115] Comparative Example 4:

[0116] The preparation method of the dealcoholized silicone sealant provided in this comparative example differs from that in Example 1 in that:

[0117] In the preparation method of modified heavy calcium carbonate, the mixing ratio of modified silane coupling agent and lauric acid is 5:1.

[0118] In the preparation of the dealcohol-type silicone sealant, 100 parts of modified heavy calcium carbonate and 100 parts of light calcium carbonate are added.

[0119] The amount of other raw materials used and the preparation process are the same as in Example 1.

[0120] Comparative Example 5:

[0121] The preparation method of the dealcoholized silicone sealant provided in this comparative example differs from that in Example 1 in that:

[0122] In the preparation of dealcohol-type silicone sealant, unmodified heavy calcium carbonate is used.

[0123] The amount of other raw materials used and the preparation process are the same as in Example 1.

[0124] Comparative Example 6

[0125] The preparation method of the dealcoholized silicone sealant provided in this comparative example differs from that in Example 1 in that:

[0126] In the preparation of modified heavy calcium carbonate, 3-(phenylamino)propyltrimethoxysilane and lauric acid are used to modify the heavy calcium carbonate.

[0127] The amount of other raw materials used and the preparation process are the same as in Example 1.

[0128] Comparative Example 7

[0129] The preparation method of the dealcoholized silicone sealant provided in this comparative example differs from that in Example 1 in that:

[0130] In the preparation of modified heavy calcium carbonate, aminopropyltriethoxysilane and lauric acid are used to modify the heavy calcium carbonate.

[0131] The amount of other raw materials used and the preparation process are the same as in Example 1.

[0132] The following performance tests were conducted on the dealcoholized silicone sealants prepared in the examples and comparative examples, and the test methods are as follows:

[0133] First, the alcohol-free single-component silicone weather-resistant sealant from the above examples and comparative examples was used to prepare H-type specimens according to GB / T13477.8-2017 Test Methods for Building Sealing Materials Part 8: Determination of Tensile Adhesion. These specimens were then cured for 28 days under standard conditions of (23±2)℃ and (50±10)% relative humidity. Subsequently, the specimens were stretched to failure on a tensile testing machine at (23±2)℃ and a speed of (5.5±0.7) mm / min. The maximum tensile strength and maximum elongation at strength were recorded. According to GB / T2941-2006 General Procedure for Specimen Preparation and Conditioning of Rubber Physical Test Methods, the specified temperature and aging time were selected for aging. The prepared H-type specimens were placed in an oven at (90±2)℃ for aging for 7 days. Following the method of GB 16776-2005 Silicone Structural Sealants for Building, the specimens were stretched to failure at (90±2)℃ at a speed of (5.5±0.7) mm / min. The maximum tensile strength and maximum elongation were recorded.

[0134] According to GB / T 13477.4-2017 "Test Methods for Building Sealing Materials Part 4: Determination of Extrudability of Original Packaging Single-Component Sealing Materials", pneumatic extrusion was performed at (23±2)℃ for 30 seconds to obtain the extrusion rate data. Detailed experimental results are shown in Tables 1 to 3 below:

[0135] Table 1. Mechanical property test results of de-alcoholized silicone sealant

[0136]

[0137] Table 2. Extrusion rates of de-alcoholized silicone sealants in Examples 1-5

[0138]

[0139] Table 2. Extrusion rates of the de-alcoholized silicone sealants in Comparative Examples 1-7

[0140]

[0141] As shown in Table 1, the de-alcoholized silicone sealants in Examples 1-5, by adding heavy calcium carbonate modified with modified silane coupling agent and lauric acid, showed improved mechanical properties, mechanical properties after aging, and adhesion compared with Comparative Example 5 without modification of heavy calcium carbonate.

[0142] Examples 1 and Comparative Examples 1-2 show that modifying heavy calcium carbonate with a modifier that combines modified silane coupling agent and lauric acid can effectively improve the adhesion after aging. However, modifying heavy calcium carbonate with a single modified silane coupling agent or lauric acid results in insufficient dispersibility, leading to a decrease in the mechanical properties of the silicone sealant.

[0143] Examples 1-5 and Comparative Examples 3-4 show that when heavy calcium carbonate is modified using a modifier composed of modified silane coupling agent and lauric acid, the higher the proportion of modified silane coupling agent, the better the extrudability. However, after reaching a certain proportion, further increases in the proportion of modified silane coupling agent will no longer increase extrudability. When the mass ratio of modified silane coupling agent to lauric acid exceeds 4:1, extrudability will decrease significantly, affecting construction performance.

[0144] Examples 1 and Comparative Examples 6-7 show that treating heavy calcium carbonate with a modifier composed of a modified silane coupling agent and lauric acid can effectively improve the mechanical properties of silicone sealant as well as its mechanical properties after aging. However, treating heavy calcium carbonate with a modifier composed of a silane coupling agent containing only partially modified silane coupling agent groups and lauric acid cannot simultaneously improve the mechanical properties, mechanical properties after aging, and workability of silicone sealant.

[0145] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0146] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A modified silane coupling agent, characterized in that, The modified silane coupling agent has the following structural formula: 。 2. A method for preparing the modified silane coupling agent according to claim 1, characterized in that, Includes the following steps: Under the protection of nitrogen or an inert gas, 3-(phenylamino)propyltrimethoxysilane and 12-aminododecanoic acid react in the presence of a catalyst to obtain the modified siloxane.

3. The modified silane coupling agent as described in claim 2, characterized in that, The reaction temperature is 20℃~30℃, and the reaction time is 2h~6h; and / or, The catalyst is at least one selected from 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride, 1-hydroxybenzotriazole, or N,N'-dicyclohexylcarbodiimide; and / or The molar ratio of 3-(phenylamino)propyltrimethoxysilane to 12-aminododecanoic acid is 2-5:1, preferably 2-3:1; and / or, The reaction is carried out in a solvent, preferably tetrahydrofuran; and / or, The molar ratio of the catalyst to the 12-aminododecanoic acid is 1:1 to 2, preferably 1:1.1 to 1.

3.

4. A modified heavy calcium carbonate, characterized in that, The modified heavy calcium carbonate is obtained by modifying heavy calcium carbonate with a modifier; The modifier includes a nonionic surfactant and the modified silane coupling agent as described in claim 1.

5. The modified heavy calcium carbonate as described in claim 4, characterized in that, The nonionic surfactant is at least one of lauric acid, palmitic acid, and fatty acids, preferably lauric acid; and / or, The mass ratio of the modified silane coupling agent to the nonionic surfactant is 1.5~4:1, preferably 2~4:1, more preferably 3~4:1; and / or, The mass ratio of the heavy calcium carbonate to the modifier is 100:1~5; preferably 100:1.5~2.

6. The use of the modified heavy calcium carbonate according to any one of claims 4-5 as a filler in a dealcoholized silicone sealant.

7. A method for preparing modified heavy calcium carbonate according to any one of claims 4-5, characterized in that, Includes the following steps: Heavy calcium carbonate water is added to a reaction vessel and heated to 70℃~80℃, and stirred to obtain a calcium carbonate suspension; The obtained calcium carbonate suspension was mixed with a modifier and stirred at 500 rpm to 70 rpm for 60 min to 70 min at 65℃ to 70℃. The mixture was then dried and ground to obtain the modified heavy calcium carbonate.

8. A de-alcoholized silicone sealant, characterized in that, The raw materials for preparing the de-alcoholized silicone sealant include fillers, wherein the fillers contain the modified heavy calcium carbonate as described in any one of claims 4-5.

9. The de-alcoholized silicone sealant as described in claim 8, characterized in that, It is prepared from the following components in parts by weight: 100 parts of α,ω-dihydroxypolydimethylsiloxane 5-10 parts of dimethyl silicone oil 150-250 parts of filler 2-6 parts of crosslinking agent 0-2 parts of silane coupling agent 2-6 parts catalyst; The filler includes light calcium carbonate and the modified heavy calcium carbonate; Preferably, it is prepared from the following components in parts by weight: 100 parts of α,ω-dihydroxypolydimethylsiloxane 5-10 parts of dimethyl silicone oil 180-220 parts of filler 3-5 parts of crosslinking agent 1-2 parts of silane coupling agent 3-5 parts catalyst; And / or, the weight ratio of the light calcium carbonate to the modified heavy calcium carbonate is 1:0.5~3, preferably 1:0.5~1.5, more preferably 1:0.9~1.1; and / or, The viscosity of the α,ω-dihydroxypolydimethylsiloxane at 25°C is 5000 mPa·s to 150000 mPa·s; and / or, The dimethyl silicone oil has a viscosity of 100 mPa·s to 10000 mPa·s at 25°C; and / or, The modified heavy calcium carbonate has a particle size of 4 μm to 10 μm; and / or, The light calcium carbonate has a particle size of 50 nm to 100 nm; and / or, The crosslinking agent is methyltrimethoxysilane; and / or, The silane coupling agent is at least one selected from γ-aminopropyltriethoxysilane, N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane, glycidyltriethoxysilane, and glycidyltrimethoxysilane; and / or The catalyst is diisopropyl bis(ethyl acetoacetate) titanate.

10. A method for preparing a dealcohol-type silicone sealant according to any one of claims 8-9, characterized in that, Includes the following steps: α,ω-dihydroxypolydimethylsiloxane, dimethyl silicone oil and filler are added to a kneader, the temperature is controlled at 60~160℃, the vacuum degree is -0.06 MPa~-0.09 MPa, dehydration and blending is carried out for 45min~300min, and then cooled to obtain the base material; The base material is added to a planetary mixer and dispersed and stirred for 5 to 10 minutes, with a vacuum degree of -0.06 MPa to -0.09 MPa and a rotation speed of 600 rpm to 720 rpm. Then, the crosslinking agent, coupling agent and catalyst are added to the planetary mixer and stirred continuously for 10 to 45 minutes, with the vacuum degree controlled at -0.045 MPa to -0.09 MPa and the rotation speed at 600 to 720 rpm, thus obtaining the de-alcoholized silicone sealant.

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