A single-component silicone sealant with fast deep curing and high temperature resistance and a preparation method thereof

Abstract

The present application relates to a kind of single-component silicone sealant of deep curing fast, high temperature resistant and preparation method thereof, the single-component silicone sealant is prepared by including the following weight parts of raw materials: alpha, omega-dihydroxyl polysiloxane 100 parts;Dimethyl silicone oil 1 part~10 parts;Filler 70 parts~140 parts;Crosslinking agent 3 parts~10 parts;Coupling agent 3 parts~13 parts;Titanium catalyst 2 parts~6 parts;The coupling agent includes compound with structural formula as shown in formula (I).The present application can improve the curing rate and heat resistance of single-component silicone sealant by adding appropriate amount of the compound as coupling agent, effectively shorten the surface dry time of single-component silicone sealant, improve deep curing rate, 80 ℃ tensile bonding strength and 80 ℃ tensile retention rate, expand the application scenario of single-component silicone sealant.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of sealant, and particularly relates to a single-component silicone sealant with fast deep curing and high temperature resistance and a preparation method thereof. BACKGROUND

[0002] The single-component dealcoholization type silicone sealant is a main variety of the silicone sealant at present, has simple construction performance, low toxicity and no odor, is widely applicable to substrates, and is a variety with the largest output and sales in the building material market at present. The traditional single-component silicone sealant on the market generally has slow curing, and needs to be in contact with moisture in the air for a long time to be cured, and cannot fully play its performance in some special scenarios such as deep joints, special bonding and insufficient air humidity. With the improvement of special requirements of users in application fields such as decoration and decoration at home, some users tend to recommend single-component silicone sealant with faster curing and high temperature resistance.

[0003] In order to accelerate the vulcanization speed of the dealcoholization type single-component silicone sealant and improve its curing performance and temperature resistance, a large amount of research work has been done by the industry and academia. Patent CN202310195838 uses capped polydimethylsiloxane, inorganic filler, reinforcing filler, crosslinking agent, first catalyst, second catalyst and coupling agent as raw materials to prepare a fast-curing dealcoholization type organic silicone sealant, but the capped polydimethylsiloxane has a higher requirement for moisture control in the production process, which is not conducive to production management. Patent CN201911150094.X uses hydroxyl-terminated polydimethylsiloxane, inorganic filler, curing agent and other additives as raw materials to prepare a fast-curing single-component room temperature vulcanization organic silicone sealant, but the curing agent must include dichloromethyltrisbutyloxime silyl, which has a certain corrosivity to some substrates and has a certain impact on human health. Patent CN201410000528.9 improves the overall curing performance by adding water-absorbing materials and air-permeable materials in the dealcoholization type transparent silicone sealant, but such water-absorbing materials and air-permeable materials generally have a high cost and may affect the mechanical properties of the sealant. SUMMARY

[0004] Therefore, the application aims to provide a single-component silicone sealant with fast deep curing and high temperature resistance, which effectively solves the problems of slow curing rate and poor high temperature performance of the single-component silicone sealant.

[0005] In a first aspect, the application provides a single-component silicone sealant, which is prepared from raw materials including the following weight parts:

[0006]

[0007] The coupling agent contains a compound as shown in the following formula (I):

[0008]

[0009] In some embodiments, the one-component silicone sealant is prepared from raw materials comprising the following parts by weight:

[0010]

[0011]

[0012] In some embodiments, the coupling agent comprises the compound and a coupling agent a;

[0013] The coupling agent a is selected from one or more of γ-glycidoxypropyltrimeth(eth)oxy silane, γ-glycidoxypropyltrimeth(eth)oxy silane, epoxycyclohexylmethyl dimeth(eth)oxy silane, chloropropyltrimeth(eth)oxy silane, γ-(2,3-epoxypropoxy)propyltrimethoxy siloxane, γ-aminopropyltrimeth(eth)oxy silane, γ-aminopropylmethyl dimeth(eth)oxy silane, N-(2-aminoethyl)-3-aminopropyltrimeth(eth)oxy silane, N-(2-aminoethyl)-3-aminopropylmethyl dimeth(eth)oxy silane, phenylaminomethyltrimeth(eth)oxy silane, γ-isocyanatopropyltrimethoxy silane, epoxylpropyltrimethoxy silane, 3-(diethylenetriaminyl)propyltrimethoxy silane;

[0014] Preferably, the parts by weight ratio of the compound and the coupling agent a is (1-5):(2-8);

[0015] More preferably, the parts by weight ratio of the compound and the coupling agent a is (2-4):(2-5).

[0016] In some embodiments, the α,ω-dihydroxypolysiloxane has a viscosity of 5 Pa.s-150 Pa.s at 25±0.5℃.

[0017] In some embodiments, the dimethyl silicone oil has a viscosity of 0.1 Pa.s-10 Pa.s at 25±0.5℃.

[0018] In some embodiments, the filler is nano-active calcium carbonate; preferably, the nano-active calcium carbonate has a particle size of 20 nm-200 nm; more preferably, the nano-active calcium carbonate has a particle size of 60 nm-150 nm.

[0019] In some embodiments, the cross-linking agent is selected from one or more of ethyl orthosilicate, propyl orthosilicate, polyethyl silicate, methyltrimethoxysilane, methyltriethoxysilane, vinyltrimethoxysilane, polymethyltriethoxysilane oligomer, phenyltrimethoxysilane, phenyltriethoxysilane, methylphenyldimethoxysilane, methylphenyldiethoxysilane, diphenyldimethoxysilane, and diphenyldiethoxysilane.

[0020] In some embodiments, the titanium-based catalyst is titanium 726.

[0021] A second aspect of the present application is to provide a method for preparing the one-component silicone sealant as described above, comprising the following steps:

[0022] (1) blending the α, ω-dihydroxyl polysiloxane, dimethyl silicone oil, and filler under vacuum dehydration to obtain a base material, and cooling;

[0023] (2) adding the base material into a planetary mixer or a high-speed dispersion mixer, then adding the cross-linking agent, and stirring and reacting under vacuum;

[0024] (3) adding the coupling agent and the titanium-based catalyst into the planetary mixer or the high-speed dispersion mixer, and stirring and reacting under vacuum, to obtain the one-component silicone sealant.

[0025] In some embodiments, the conditions for vacuum dehydration blending in step (1) are as follows: the temperature is 80-150°C, the vacuum degree is -0.06 MPa to -0.099 MPa, and the vacuum dehydration blending time is 30-300 min; preferably, the temperature is 100-130°C, the vacuum degree is -0.06 MPa to -0.099 MPa, and the vacuum dehydration blending time is 100-200 min.

[0026] In some embodiments, the conditions for vacuum stirring in step (2) are as follows: the vacuum degree is -0.02 MPa to -0.04 MPa, and the rotating speed is 10-800 rpm; preferably, the vacuum degree is -0.02 MPa to -0.04 MPa, and the rotating speed is 100-500 rpm.

[0027] In some embodiments, the conditions for vacuum stirring in step (3) are as follows: the vacuum degree is -0.06 MPa to -0.099 MPa, and the rotating speed is 10-800 rpm; preferably, the vacuum degree is -0.06 MPa to -0.099 MPa, and the rotating speed is 100-500 rpm.

[0028] In some embodiments, the reaction time in step (2) is 5-30 min, preferably 10-20 min.

[0029] In some embodiments, the reaction time in step (3) is 30 min to 120 min, preferably 30 min to 80 min.

[0030] The present application provides a single-component silicone sealant, by adding an appropriate amount of the compound as a coupling agent in the single-component silicone sealant, the curing rate and heat resistance can be improved at the same time, the surface drying time of the single-component silicone sealant is effectively shortened, the deep curing rate, 80℃ tensile bonding strength and 80℃ tensile retention rate are improved, and the application scenarios of the single-component silicone sealant are expanded.

[0031] The single-component silicone sealant of the present application is environmentally friendly, the small molecules released during the curing process are alcohol small molecules, a neutral curing system is adopted, and there is no corrosivity to building materials such as metals, glasses and concretes, and the application is wide. DETAILED DESCRIPTION

[0032] In order to facilitate the understanding of the present application, the present application will be described more fully below. The present application can be realized in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive.

[0033] The experimental methods in the following examples not specifically noted are generally carried out according to the conventional conditions or according to the conditions suggested by the manufacturers. The various common chemical reagents used in the examples are all commercially available products. Unless otherwise defined, all technical and scientific terms used in the present application have the same meaning as understood by those skilled in the art to which the present application belongs. The terms used in the specification of the present application are only for the purpose of describing the specific embodiments and are not used to limit the present application. The term "and / or" used in the present application includes any and all combinations of one or more related listed items.

[0034] In addition, as used in the present application, the term "or" is an inclusive "or" and is equivalent to the term "and / or", unless the context clearly indicates otherwise. The term "based on" is not exclusive and allows other factors not described, unless the context clearly indicates otherwise. In addition, throughout the specification, the meanings of "one", "a" and "said / the" include plural referents. The meaning in "in" includes "in" and "on".

[0035] In some embodiments of the present application, a single-component silicone sealant is provided, which is prepared from raw materials including the following parts by weight:

[0036]

[0037] The coupling agent comprises a compound shown in the following formula (I):

[0038]

[0039] By adding an appropriate amount of the compound as a coupling agent, the curing rate and heat resistance of the one-component silicone sealant of the present application can be simultaneously improved, the surface dry time of the one-component silicone sealant is effectively shortened, the deep curing rate, 80℃ tensile bonding strength and 80℃ tensile retention rate are improved, and the application scenarios of the one-component silicone sealant are expanded.

[0040] The compound is generated by the reaction of the ester group of n-butyl benzoate with the primary amine group in 3-(divinyltriamine) propyl trimethoxysilane, and the synthesis route is as follows:

[0041]

[0042] In some preferred embodiments, the preparation method of the compound comprises the following steps: reacting n-butyl benzoate and 3-(divinyltriamine) propyl trimethoxysilane, vacuum distillation, and separation.

[0043] In some preferred embodiments, the preparation method of the compound comprises the following steps: adding 3-(divinyltriamine) propyl trimethoxysilane into a solvent, uniformly mixing, then adding n-butyl benzoate, heating to 60℃-100℃ for reflux reaction for 4h-12h, then removing small molecules by vacuum distillation, and separation.

[0044] In some preferred embodiments, the molar ratio of 3-(divinyltriamine) propyl trimethoxysilane to n-butyl benzoate is (0.8-1.2):1, preferably (0.9-1.1):1.

[0045] In some preferred embodiments, the temperature is heated to 70℃-90℃ for reflux reaction for 4h-12h.

[0046] In some preferred embodiments, the separation method is column chromatography.

[0047] In some preferred embodiments, the solvent is an alcohol solvent, for example, including but not limited to n-butanol, propanol, n-propanol, and isopropanol.

[0048] The present application is further described in detail below in combination with specific examples.

[0049] The compound shown in formula (I) is named as a modified aminosilane coupling agent in the present application.

[0050] The modified amino silane coupling agent used in the following examples is prepared by the following method: 1 mol of 3-(diethylenetriamine) propyl trimethoxysilane and 0.5 mol of n-butanol are added to a four-necked flask with a stirrer and a thermometer and protected by nitrogen, after being mixed well, 1 mol of n-butyl benzoate is added, the temperature is raised to 80°C and refluxed for 8 hours, then small molecules are removed by distillation under reduced pressure, and the target product is obtained by column chromatography. The yield is 92.32%.

[0051] By infrared detection, no primary amine (-NH2) group stretching vibration absorption peak is found near 3370 cm -1 , -C=ONH- containing oxygen amino vibration absorption peak appears near 1740 cm -1 , C-H stretching vibration absorption peak appears near 2837 cm -1 and 2938 cm -1 , C-N stretching vibration absorption peak appears near 1457 cm -1 and 1465 cm -1 , Si-O-C stretching vibration absorption peak appears near 1077 cm -1 and 1085 cm -1 . It is proved that the modified amino silane coupling agent shown in the following formula (I) is successfully prepared:

[0052]

[0053] The present application is further described in detail in combination with specific examples.

[0054] Example 1

[0055] This example provides a one-component silicone sealant, which is prepared by the following method:

[0056] Base preparation: first, 100 parts of α, ω-dihydroxy polydimethylsiloxane with a viscosity of 50000 mPa·s, 110 parts of active calcium carbonate with a particle size of 60 nm, and 5 parts of dimethyl silicone oil with a viscosity of 350 mPa·s are added to a kneader, and then dehydrated and blended for 120 min under the conditions of a temperature of 120°C and a vacuum degree of-0.09 MPa to obtain a base, which is then cooled for standby;

[0057] Sealant preparation: the above base was added to a planetary mixer, 5 parts of polymethyl triethoxysilane oligomer was added, and the base was chemically reacted at a vacuum degree of -0.04 MPa and a rotation speed of 300 rpm for 15 minutes; finally, 2 parts of γ-aminopropyl trimethoxysilane, 0.5 parts of γ-glycidyl ether oxypropyl trimethoxysilane, 1 part of modified amino silane coupling agent, and 4 parts of titanium 726 (purchased from DuPont, USA, the same in the following examples) were added, and the chemical reaction was carried out at a vacuum degree of -0.09 MPa and a rotation speed of 300 rpm for 40 minutes to prepare a silicone sealant.

[0058] Example 2

[0059] This example provides a one-component silicone sealant, which is prepared by the following method:

[0060] Base preparation: first, 100 parts of α, ω-dihydroxy polydimethylsiloxane with a viscosity of 50000 mPa·s, 110 parts of active calcium carbonate with a particle size of 60 nm, and 5 parts of dimethyl silicone oil with a viscosity of 350 mPa·s were added to a kneader, and dehydrated and blended at a temperature of 120°C and a vacuum degree of -0.09 MPa for 120 min to obtain a base, which was then cooled for standby;

[0061] Sealant preparation: the above base was added to a planetary mixer, 5 parts of polymethyl triethoxysilane oligomer was added, and the base was chemically reacted at a vacuum degree of -0.04 MPa and a rotation speed of 300 rpm for 15 minutes; finally, 2 parts of γ-aminopropyl trimethoxysilane, 0.5 parts of γ-glycidyl ether oxypropyl trimethoxysilane, 1 part of modified amino silane coupling agent, and 4 parts of titanium 726 (purchased from DuPont, USA, the same in the following examples) were added, and the chemical reaction was carried out at a vacuum degree of -0.09 MPa and a rotation speed of 300 rpm for 40 minutes to prepare a silicone sealant.

[0062] Example 3

[0063] This example provides a one-component silicone sealant, which is prepared by the following method:

[0064] Base preparation: first, 100 parts of α, ω-dihydroxy polydimethylsiloxane with a viscosity of 50000 mPa·s, 110 parts of active calcium carbonate with a particle size of 60 nm, and 5 parts of dimethyl silicone oil with a viscosity of 350 mPa·s were added to a kneader, and dehydrated and blended at a temperature of 120°C and a vacuum degree of -0.09 MPa for 120 min to obtain a base, which was then cooled for standby;

[0065] Sealant preparation: the above base material is added to a planetary mixer, 5 parts of polymethyl triethoxysilane oligomer are added, and chemical reaction is carried out at a vacuum degree of-0.04 MPa and a rotating speed of 300 rpm for 15 minutes with the base material; finally, 2 parts of γ-aminopropyl trimethoxysilane, 0.5 parts of γ-glycidyl ether oxypropyl trimethoxysilane, 3 parts of modified amino silane coupling agent, and 4 parts of titanium 726 are added, and chemical reaction is carried out at a vacuum degree of-0.09 MPa and a rotating speed of 300 rpm for 40 minutes to prepare a silicone sealant.

[0066] Example 4

[0067] The present example provides a one-component silicone sealant, which is prepared by the following method:

[0068] Base material preparation: first, 100 parts of α, ω-dihydroxy polydimethylsiloxane with a viscosity of 50000 mPa·s, 110 parts of active calcium carbonate with a particle size of 60 nm, and 5 parts of dimethyl silicone oil with a viscosity of 350 mPa·s are added to a kneader, and dehydration blending is carried out at a temperature of 120°C and a vacuum degree of-0.09 MPa for 120 min to obtain a base material, which is then cooled for standby;

[0069] Sealant preparation: the above base material is added to a planetary mixer, 5 parts of polymethyl triethoxysilane oligomer are added, and chemical reaction is carried out at a vacuum degree of-0.04 MPa and a rotating speed of 300 rpm for 15 minutes with the base material; finally, 2 parts of γ-aminopropyl trimethoxysilane, 0.5 parts of γ-glycidyl ether oxypropyl trimethoxysilane, 3 parts of modified amino silane coupling agent, and 4 parts of titanium 726 are added, and chemical reaction is carried out at a vacuum degree of-0.09 MPa and a rotating speed of 300 rpm for 40 minutes to prepare a silicone sealant.

[0070] Comparative Example 1

[0071] The present comparative example provides a one-component silicone sealant, Except that no modified amino silane coupling agent was added, otherwise All were the same as in Example 3, The preparation method is as follows:

[0072] Base material preparation: first, 100 parts of α, ω-dihydroxy polydimethylsiloxane with a viscosity of 50000 mPa·s, 110 parts of active calcium carbonate with a particle size of 60 nm, and 5 parts of dimethyl silicone oil with a viscosity of 350 mPa·s are added to a kneader, and dehydration blending is carried out at a temperature of 120°C and a vacuum degree of-0.09 MPa for 120 min to obtain a base material, which is then cooled for standby;

[0073] Sealant preparation: the above base material was added to a planetary mixer, 5 parts of polymethyl triethoxysilane oligomer was added, and the base material was chemically reacted at a vacuum degree of -0.04 MPa and a rotation speed of 300 rpm for 15 minutes; finally, 2 parts of γ-aminopropyl trimethoxysilane, 0.5 parts of γ-glycidyl ether oxypropyl trimethoxysilane, and 4 parts of titanium 726 were added, and the chemical reaction was carried out at a vacuum degree of -0.09 MPa and a rotation speed of 300 rpm for 40 minutes to prepare a silicone sealant.

[0074] Comparative Example 2:

[0075] The present comparative example provides a one-component silicone sealant, Except that the modified amino silane coupling agent was replaced with an equivalent amount of Coupling agent a, otherwise all were the same as in Example 3, The preparation method is as follows:

[0076] Base material preparation: first, 100 parts of α, ω-dihydroxy polydimethylsiloxane with a viscosity of 50000 mPa·s, 110 parts of active calcium carbonate with a particle size of 60 nm, and 5 parts of dimethyl silicone oil with a viscosity of 350 mPa·s were added to a kneader, and dehydrated and blended at a temperature of 120°C and a vacuum degree of -0.09 MPa for 120 min to obtain a base material, which was then cooled for standby;

[0077] Sealant preparation: the above base material was added to a planetary mixer, 5 parts of polymethyl triethoxysilane oligomer was added, and the base material was chemically reacted at a vacuum degree of -0.04 MPa and a rotation speed of 300 rpm for 15 minutes; finally, 2 parts of γ-aminopropyl trimethoxysilane, 0.5 parts of γ-glycidyl ether oxypropyl trimethoxysilane, and 4 parts of titanium 726 were added, and the chemical reaction was carried out at a vacuum degree of -0.09 MPa and a rotation speed of 300 rpm for 40 minutes to prepare a silicone sealant.

[0078] The raw materials for the above examples and comparative examples are shown in Table 1.

[0079] Table 1: List of raw material components for examples and comparative examples

[0080]

[0081] The following properties of the one-component silicone sealant prepared in the above examples and comparative examples were detected:

[0082] Tack-free time: tested according to the requirements in GB / T 13477.5.

[0083] Curing rate: the sealant was extruded onto A4 paper (cylindrical shape), and placed at 23°C and 50% relative humidity for 24 h, then the adhesive strip was cut open and the sample curing thickness was detected with a curing depth plate to characterize the curing rate.

[0084] 23℃ Tensile adhesion: tested according to JG / T 475-2015 5.9.

[0085] 80℃ Tensile adhesion: tested according to JG / T 475-2015 5.9.2 and retention rate calculated according to 5.1.3.

[0086] Test results are filled in Table 2.

[0087] Table 2 Performance test results of examples and comparative examples

[0088]

[0089]

[0090] By comparing examples 1-4 and comparative examples 1-2, it can be seen that the surface drying time of the sealant is significantly reduced and the deep curing rate is significantly improved after adding the modified amino silane coupling agent. The main reason may be that the addition of the modified amino silane coupling agent accelerates the crosslinking reaction speed of the sealant. While increasing the crosslinking density of the colloidal sealant, the mechanical properties of the sealant such as tensile strength are also effectively improved, and the 80℃ tensile adhesion strength and 80℃ tensile retention rate are significantly improved, indicating that the heat resistance is improved. However, the deep curing rate and heat resistance of the sealant are not better improved with more amount of the modified amino silane coupling agent. When the amount of the modified amino silane coupling agent is greater than 5 parts, the deep curing rate of the sealant begins to slow down. It may be that when the amount of the modified amino silane coupling agent is too much, although the surface drying time is shortened, the surface layer of the sealant is crosslinked too quickly, which forms a steric effect and blocks the penetration of external water vapor to the deep layer of the sealant, thereby slowing down the curing speed. Considering comprehensively, in order to balance the surface drying and deep curing speed performance and high temperature mechanical properties of the sealant, the amount of the modified amino silane coupling agent is preferably 1-5 parts, and the comprehensive performance of the sealant is best when the amount of the modified amino silane coupling agent is 3 parts.

[0091] By comparing example 3 and comparative example 1, it can be seen that when the modified amino silane coupling agent of the application is not added, the surface drying time of the sealant increases, the deep curing speed decreases, and the high temperature mechanical properties deteriorate. Although the amount of other coupling agents is increased in comparative example 2, the surface drying and deep curing speed performance and high temperature mechanical properties of the sealant are not significantly improved, indicating that increasing the amount of conventional coupling agents cannot improve the rapid curing and high temperature resistance of the sealant without adding the modified amino silane coupling agent provided by the application.

[0092] The above embodiments only express several implementation manners of the present application, and the description is relatively specific and detailed, but should not be understood as a limitation on the patent scope of the present application. It should be noted that, for ordinary skilled persons in the art, several modifications and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A one-component silicone sealant, characterized by, is prepared from raw materials comprising the following weight parts: α, ω-dihydroxypolydimethylsiloxane 100 parts; dimethyl silicone oil 1 part to 10 parts; filler 70 parts to 140 parts; crosslinking agent 3 parts to 10 parts; coupling agent 3 parts to 13 parts; titanium-based catalyst 2 parts to 6 parts; the coupling agent comprises a compound with the following structural formula (I): Formula (I).

2. The one-part silicone sealant of claim 1, wherein is prepared from raw materials comprising the following weight parts: α, ω-dihydroxypolydimethylsiloxane 100 parts; dimethyl silicone oil 3 parts to 8 parts; filler 90 parts to 120 parts; crosslinking agent 4 parts to 7 parts; coupling agent 4 parts to 9 parts; titanium-based catalyst 3 parts to 5 parts.

3. The one-part silicone sealant of claim 1, wherein the coupling agent comprises the compound and coupling agent a; the coupling agent a is selected from one or more of γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, epoxycyclohexylmethyldimethoxysilane, epoxycyclohexylmethyldiethoxysilane, chloropropyltrimethoxysilane, chloropropyltriethoxysilane, γ-(2, 3-epoxypropoxy) propyltrimethoxysiloxane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropylmethyldimethoxysilane, γ-aminopropylmethyldiethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropyltriethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldiethoxysilane, phenylaminomethyltrimethoxysilane, phenylaminomethyltriethoxysilane, γ-isocyanatepropyltrimethoxysilane, epoxylpropyltrimethoxysilane, 3- (diethylenetriamine) propyltrimethoxysilane.

4. The one-part silicone sealant of claim 3, wherein The weight parts ratio of the compound and coupling agent a is (1 to 5) : (2 to 8).

5. The one-part silicone sealant of claim 4, wherein The weight parts ratio of the compound and coupling agent a is (2 to 4) : (2 to 5).

6. The one-part silicone sealant according to claim 1 or 2, wherein The viscosity of the α, ω-dihydroxypolydimethylsiloxane at 25 ± 0.5 ℃ is 5 Pa.s to 150 Pa.s.

7. The one-part silicone sealant according to claim 1 or 2, wherein The viscosity of the dimethyl silicone oil at 25 ± 0.5 ℃ is 0.1 Pa.s to 10 Pa.s.

8. The one-part silicone sealant according to claim 1 or 2, wherein The filler is nano active calcium carbonate.

9. The one-part silicone sealant of claim 8, wherein, The particle size of the nano active calcium carbonate is 20 nm to 200 nm.

10. The one-part silicone sealant according to claim 1 or 2, wherein The crosslinking agent is selected from one or more of tetraethyl orthosilicate, tetrapropyl orthosilicate, polyethyl orthosilicate, methyltrimethoxysilane, methyltriethoxysilane, vinyltrimethoxysilane, polymethyltriethoxysilane oligomer, phenyltrimethoxysilane, phenyltriethoxysilane, methylphenyldimethoxysilane, methylphenyldiethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane; and / or, The titanium-based catalyst is titanium 726.

11. The method of preparing a one-component silicone sealant according to any one of claims 1 to 10, wherein comprising the following steps: (1) The α, ω-dihydroxypolydimethylsiloxane, dimethyl silicone oil, and filler are vacuum dehydrated and blended to obtain a base material, which is cooled; (2) The base material is added to a planetary mixer or a high-speed dispersion mixer, and then the crosslinking agent is added, and vacuum stirring reaction is performed; (3) The coupling agent and the titanium catalyst are added into a planetary mixer or a high-speed dispersion mixer, and vacuum stirring reaction is carried out, and then the product is obtained.

12. The production method according to claim 11, wherein The conditions for vacuum dehydration blending in step (1) are as follows: the temperature is 80-150°C, the vacuum degree is -0.06-0.099 MPa, and the dehydration blending time is 30-300 min; and / or, The vacuum stirring conditions in step (2) are as follows: the vacuum degree is -0.02-0.04 MPa, and the rotating speed is 10-800 rpm; and / or, The vacuum stirring conditions in step (3) are as follows: the vacuum degree is -0.06-0.099 MPa, and the rotating speed is 10-800 rpm.

13. The production method according to claim 11 or 12, characterized by, The reaction time in step (2) is 5-30 min; and / or, The reaction time in step (3) is 30-120 min.

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