Tin-containing catalyst for two-component sealant as well as preparation method and application of tin-containing catalyst
By preparing a two-component de-alcoholized silicone sealant containing a tin catalyst, the problem of poor storage stability of traditional sealants has been solved, enabling long-term storage and efficient curing, which is suitable for high-precision production in the new energy and electronics industries.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SHANGHAI HUITIAN NEW CHEMICAL MATERIALS CO LTD
- Filing Date
- 2025-11-28
- Publication Date
- 2026-05-01
AI Technical Summary
Traditional two-component alcohol-based silicone sealants have poor storage stability at a 1:1 ratio and are prone to failure to cure over long periods of time. Furthermore, existing catalysts are either expensive or have poor storage stability, making it difficult to meet the high-precision and large-scale production requirements of the new energy and electronics industries.
A tin-containing catalyst is prepared by mixing alkyl tin oxide or tin tetrachloride with a monocarboxylic acid containing carbon-carbon double bonds in a specific molar ratio, combined with glacial acetic acid and vacuum treatment. The catalyst is used to prepare a two-component dealcoholized silicone sealant containing a specific ratio of α,ω-dihydroxy polydimethylsiloxane, alkoxy-terminated polydimethylsiloxane and solid filler.
Significantly extends the shelf life of sealant to 6-12 months, reduces production costs, improves curing speed, mechanical properties and adhesion, and meets the needs of high-precision and large-scale production.
Smart Images
Figure SMS_11 
Figure QLYQS_1
Abstract
Description
Technical Field
[0001] This invention belongs to the field of adhesive technology, specifically relating to a tin-containing catalyst for two-component sealants, its preparation method, and its application. Background Technology
[0002] Two-component alcohol-free silicone sealants are widely used in various industries such as new energy, construction, and electronics due to their advantages such as fast curing speed, good adhesion, low toxicity, and easy storage. However, the mixing ratios of traditional two-component alcohol-free sealants vary considerably, with volume or mass ratios often ranging from 4 to 15:1. This results in disadvantages such as difficulty in controlling the mixing ratio, slow application speed, high requirements for mixing accuracy, and poor resistance to fluctuations, making them unsuitable for the high-precision, continuous, and large-scale production requirements of industries such as new energy and electronics.
[0003] To address the aforementioned shortcomings, two-component, alcohol-free silicone sealants with a volume or mass ratio of (1~2):1 have emerged on the market, combining most of the advantages of the aforementioned sealants. However, these newly developed two-component, alcohol-free silicone sealants suffer from poor storage stability, easily failing to cure over long periods, especially sealants with a 1:1 mass or volume ratio. To solve this problem, technicians have added 30%~60% alkoxy-terminated polyethers or alkoxy-terminated polydimethylsiloxanes to the curing agent. Alkoxy-terminated polydimethylsiloxanes generally undergo two synthesis processes. One is the addition method, where vinyl-terminated polydimethylsiloxane, hydrogen-containing double-terminated polyether, and vinylsiloxane undergo an addition reaction to obtain the alkoxy-terminated polydimethylsiloxane. This method is more expensive and less economical, and the surface drying time gradually slows down with prolonged storage, affecting construction efficiency. Most commercially available products use this method. Another type is condensation-type alkoxy-terminated polydimethylsiloxane, which is prepared by direct condensation reaction of hydroxyl-terminated polydimethylsiloxane and alkoxysilane. It has a lower cost, but the sealant prepared by this method has significantly worse storage stability than the sealant produced by alkoxy-terminated polydimethylsiloxane prepared by the addition method. As the storage time is extended, the surface drying time of the sealant will be significantly prolonged. Summary of the Invention
[0004] To address the aforementioned problems, this invention provides a tin-containing catalyst. This catalyst, used in the process of preparing a two-component dealcoholized silicone sealant from alkoxy-terminated polydimethylsiloxane, enables the prepared sealant to possess the advantages of fast curing speed, good mechanical properties, strong adhesion, and long shelf life.
[0005] Specifically, in order to achieve the above objectives, the present invention adopts the following technical solution: A tin-containing catalyst has the following structural formula: In this context, R is a C4-C12 alkyl group; when x=0 or 1, R' is a C11-C17 alkenyl group; when x=2, R' is a C13-C17 alkenyl group.
[0006] In the preferred scheme, x = 0 or 1.
[0007] The preparation method of the tin-containing catalyst includes the following steps: S1. Add alkyl tin oxide or tin tetrachloride to a monocarboxylic acid containing a carbon-carbon double bond in a molar ratio of 1:(4.2-1.05x) and mix thoroughly to obtain mixture M; S2. Add 1% to 5% of glacial acetic acid by mass of the mixture M, heat to 70°C to 80°C while stirring, and keep warm and stirring for 1 to 2 hours; S3. After the heat preservation is completed, the temperature is raised to 105℃~110℃ and vacuumed until no low-boiling-point flow occurs, thus obtaining the tin-containing catalyst.
[0008] This invention also provides the application of the tin-containing catalyst in a two-component dealcoholized silicone sealant. The two-component dealcoholized silicone sealant comprises component A and component B; component A consists of the following components: 100 parts α,ω-dihydroxypolydimethylsiloxane, 0-30 parts α,ω-dimethylpolydimethylsiloxane, and 30-180 parts a first solid filler; component B consists of the following components: 100 parts alkoxy-terminated polydimethylsiloxane, 0-100 parts α,ω-dimethylpolydimethylsiloxane, 30-300 parts a second solid filler, 3-30 parts a crosslinking agent, 2-10 parts a silane coupling agent, and 0.05-2 parts of the tin-containing catalyst.
[0009] In a preferred embodiment, the viscosity of α,ω-dihydroxypolydimethylsiloxane in component A is 1500~100000 mPa·s.
[0010] In a preferred embodiment, the α,ω-dimethylpolydimethylsiloxane content in component A is 0 to 20 parts.
[0011] In a preferred embodiment, the first solid filler is 60 to 160 parts.
[0012] In a preferred embodiment, the first solid filler is at least one of nano-calcium carbonate, heavy calcium carbonate, aluminum hydroxide, silica powder, alumina, silica, carbon black, and titanium dioxide.
[0013] In a preferred embodiment, the viscosity of both α,ω-dimethylpolydimethylsiloxane in component A and α,ω-dimethylpolydimethylsiloxane in component B is 100~60000 mPa·s.
[0014] In a preferred embodiment, the amount of α,ω-dimethylpolydimethylsiloxane in component B is 0 to 30 parts.
[0015] In a preferred embodiment, the viscosity of the alkoxy-terminated polydimethylsiloxane in component B is 1500~80000 mPa·s.
[0016] In a preferred embodiment, the second solid filler is 60 to 200 parts.
[0017] In a preferred embodiment, the second solid filler is at least one of nano-calcium carbonate, heavy calcium carbonate, aluminum hydroxide, silica powder, alumina, silica, carbon black, and titanium dioxide.
[0018] In a preferred embodiment, the crosslinking agent in component B is 4 to 20 parts.
[0019] In a preferred embodiment, the crosslinking agent in component B is at least one of alkyltrialkoxysilane, dialkyldialkoxysilane, tetraalkoxysilane, phenyltrialkoxysilane, and vinyltrialkoxysilane.
[0020] In a preferred embodiment, the silane coupling agent in component B is 3 to 8 parts.
[0021] In a preferred embodiment, the silane coupling agent in component B is γ-aminopropyltrialkoxysilane, γ-glycidyl ether alkyltrialkoxysilane, N-(β-aminoethyl)-γ-aminopropyltrialkoxysilane, N-n-butyl-3-aminopropyltrialkoxysilane, bis-[3-(trialkoxysilane)-propyl]-amine, or Dynasylan. ® At least one of 1146, JH-AP1231, and JH-AP1234.
[0022] In a preferred embodiment, the tin-containing catalyst is 0.05 to 1 part.
[0023] This invention also provides a method for preparing the two-component dealcoholized silicone sealant, comprising the following steps: Adding the raw material of component A to a reaction vessel, starting stirring, and after the first solid filler is completely impregnated, applying a vacuum and stirring until the mixture is uniform and fine, thus obtaining component A; adding the alkoxy-terminated polydimethylsiloxane, α,ω-dimethylpolydimethylsiloxane, and the second solid filler from component B to the reaction vessel, starting stirring, and after the second solid filler is completely impregnated, applying a vacuum, and continuing stirring at 110℃~130℃ for 2~4 hours, and cooling to obtain the base adhesive; adding a crosslinking agent, a silane coupling agent, and the tin-containing catalyst to the base adhesive, and stirring until uniformly mixed under conditions of temperature <50℃ and vacuum, thus obtaining component B; mixing component A and component B uniformly to obtain the two-component dealcoholized silicone sealant.
[0024] In a preferred embodiment, the mass ratio of component A to component B is (0.5~2):1.
[0025] Compared with the prior art, the technical solution of the present invention has the following beneficial effects: (1) The present invention provides a new tin-containing catalyst. When the tin-containing catalyst is used in the process of preparing two-component de-alcoholized silicone sealant using alkoxy-terminated polydimethylsiloxane (including alkoxy-terminated polydimethylsiloxane prepared by addition and condensation) as raw material, the prepared sealant can have excellent storage stability and significantly extend the storage period of the sealant to 6 to 12 months.
[0026] (2) When the tin-containing catalyst provided by the present invention is used to produce sealant using alkoxy-terminated polydimethylsiloxane prepared by condensation as raw material, it can significantly reduce production steps and reduce production costs.
[0027] (3) Compared with the commonly used organotin catalysts such as dibutyltin diacetate and dibutyltin dilaurate in the prior art, the two-component de-alcoholized silicone sealant prepared by the tin-containing catalyst provided in this invention also has the advantages of fast curing speed, good mechanical properties and strong adhesion. Detailed Implementation
[0028] The following description, in conjunction with embodiments, clearly and completely describes the technical solutions of this application, so that those skilled in the art can fully understand this application. Obviously, the described embodiments are merely some preferred embodiments of this application, and not all embodiments. Any equivalent modifications or substitutions made by those skilled in the art to the following embodiments without creative effort are within the protection scope of this application.
[0029] Unless otherwise stated, the parts in the following embodiments and comparative examples are parts by mass. Ordinal numbers used in this application, such as "first," "second," etc., are for descriptive purposes only to distinguish similar or identical objects and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features.
[0030] This application provides a tin-containing catalyst with the following structural formula: Where R=C m H 2m+1 m is an integer from 4 to 12; x is a natural number from 0 to 2, R'=C n H 2n-1 When x=0 or 1, n is an integer from 11 to 17; when x=2, n is an integer from 13 to 17.
[0031] In some preferred embodiments, x = 0. As an example, the tin-containing catalyst is Sn(COOC) 11 H 21 4. Sn(COOC) 13 H 25 4. Sn(COOC) 17 H 33 One or more of 4.
[0032] In some other preferred embodiments, x=1. As an example, the tin-containing catalyst is C4H9Sn(COOC) 17 H 33 3. C4H9Sn(COOC) 13 H 25 3. C8H 17 Sn(COOC 11 H 21 )3 or more of them.
[0033] Specific embodiments of this application also provide a method for preparing the tin-containing catalyst, including the following steps: S1. Alkyl tin oxide or tin tetrachloride (SnCl4) and a monocarboxylic acid containing a carbon-carbon double bond are added to a reaction vessel at a molar ratio of 1:(4.2-1.05x) and mixed thoroughly to obtain mixture M. The alkyl group in the alkyl tin oxide is C. m H 2m+1 In monocarboxylic acids containing carbon-carbon double bonds, the alkenyl group containing the carbon-carbon double bond is C. n H 2n-1 .
[0034] S2. Add 1% to 5% of glacial acetic acid by mass of mixture M, heat to 70°C to 80°C while stirring, and keep warm and stirring for 1 to 2 hours.
[0035] After the heat preservation in step S2 is completed, the temperature is raised to 105℃~110℃ and a vacuum is drawn (vacuum degree is -0.095~-0.100MPa) until no low-boiling material flows out, and the tin-containing catalyst is obtained.
[0036] In some specific implementations, x=0, the tin source in step S1 is tin tetrachloride, and the molar ratio of tin tetrachloride to a monocarboxylic acid containing a carbon-carbon double bond is 1:4.2.
[0037] In some other specific embodiments, x=1, the tin source in step S1 is alkyl tin oxide, and the molar ratio of alkyl tin oxide to monocarboxylic acid containing carbon-carbon double bonds is 1:3.15.
[0038] In some other specific embodiments, x=2, the tin source in step S1 is dialkyltin oxide, and the molar ratio of dialkyltin oxide to monocarboxylic acid containing carbon-carbon double bonds is 1:2.1.
[0039] As an example, the mass percentage of glacial acetic acid in mixture M in step S2 may be 1%, 2%, 3%, 4%, or 5%, but is not limited to this.
[0040] As an example, step S2 may involve heating to 70°C, 72°C, 75°C, 78°C, or 80°C, but is not limited to these.
[0041] As an example, the heat preservation time in step S2 is 60 min, 65 min, 70 min, 75 min, 80 min, 90 min, 100 min, 110 min or 120 min, and is not limited to this.
[0042] As an example, step S3 may involve raising the temperature to 105°C, 108°C, or 110°C, but is not limited to these.
[0043] This application also provides a two-component dealcoholized silicone sealant, comprising component A and component B. Component A consists of: 100 parts α,ω-dihydroxypolydimethylsiloxane, 0-30 parts α,ω-dimethylpolydimethylsiloxane, and 30-180 parts a first solid filler. Component B consists of: 100 parts alkoxy-terminated polydimethylsiloxane, 0-100 parts α,ω-dimethylpolydimethylsiloxane, 30-300 parts a second solid filler, 3-30 parts a crosslinking agent, 2-10 parts a silane coupling agent, and 0.05-2 parts a tin-containing catalyst.
[0044] As an example, the mass fractions of α,ω-dimethylpolydimethylsiloxane in component A are 0, 1, 2, 3, 5, 8, 10, 12, 15, 18, 20, 25, 28, or 30, and are not limited thereto.
[0045] In some preferred embodiments, the mass fraction of α,ω-dimethylpolydimethylsiloxane in component A is 0 to 20 parts.
[0046] As an example, the mass fraction of the first solid filler in component A is 30 parts, 35 parts, 40 parts, 45 parts, 50 parts, 55 parts, 60 parts, 65 parts, 70 parts, 75 parts, 80 parts, 85 parts, 90 parts, 95 parts, 100 parts, 105 parts, 110 parts, 115 parts, 120 parts, 125 parts, 130 parts, 135 parts, 140 parts, 145 parts, 150 parts, 155 parts, 160 parts, 165 parts, 170 parts, 175 parts, or 180 parts, and is not limited thereto.
[0047] In some preferred embodiments, the mass fraction of the first solid filler in component A is 60 to 160 parts.
[0048] As an example, the mass fractions of α,ω-dimethylpolydimethylsiloxane in component B are 0, 1, 2, 3, 5, 8, 10, 12, 15, 18, 20, 25, 30, 35, 40, 50, 60, 70, 80, 90, or 100 parts, and are not limited thereto.
[0049] In some preferred embodiments, the mass fraction of α,ω-dimethylpolydimethylsiloxane in component B is 0 to 30 parts.
[0050] As an example, the mass fraction of the second solid filler in component B is 30 parts, 35 parts, 40 parts, 45 parts, 50 parts, 55 parts, 60 parts, 65 parts, 70 parts, 75 parts, 80 parts, 85 parts, 90 parts, 95 parts, 100 parts, 105 parts, 110 parts, 120 parts, 130 parts, 140 parts, 150 parts, 160 parts, 170 parts, 180 parts, 190 parts, 200 parts, 220 parts, 240 parts, 260 parts, 280 parts, or 300 parts, and is not limited thereto.
[0051] In some preferred embodiments, the mass fraction of the second solid filler in component B is 60 to 200 parts.
[0052] As an example, the mass fraction of the crosslinking agent in component B is 3, 4, 5, 6, 8, 10, 15, 16, 18, 20, 25, 28 or 30 parts, and is not limited thereto.
[0053] In some preferred embodiments, the crosslinking agent in component B is 4 to 20 parts by mass.
[0054] As an example, the mass fraction of silane coupling agent in component B may be 2, 3, 4, 5, 6, 7, 8, 9, or 10 parts, and is not limited thereto.
[0055] In some preferred embodiments, the mass fraction of the silane coupling agent in component B is 3 to 8 parts.
[0056] As an example, the mass fraction of the tin-containing catalyst in component B is 0.05 parts, 0.06 parts, 0.07 parts, 0.08 parts, 0.09 parts, 0.1 parts, 0.15 parts, 0.2 parts, 0.25 parts, 0.3 parts, 0.35 parts, 0.4 parts, 0.45 parts, 0.5 parts, 0.55 parts, 0.6 parts, 0.65 parts, 0.7 parts, 0.75 parts, 0.8 parts, 0.85 parts, 0.9 parts, 0.95 parts, 1 part, 1.1 parts, 1.2 parts, 1.5 parts, or 2 parts, and is not limited thereto.
[0057] In some preferred embodiments, the mass fraction of the tin-containing catalyst in component B is 0.05 to 1 part.
[0058] In some preferred embodiments, the viscosity of α,ω-dihydroxypolydimethylsiloxane in component A is 1500~80000 mPa·s; for example, 1500 mPa·s, 1600 mPa·s, 1700 mPa·s, 1800 mPa·s, 2000 mPa·s, 2500 mPa·s, 3000 mPa·s, 5000 mPa·s, 6000 mPa·s, 8000 mPa·s, 10000 mPa·s, 11000 mPa·s, 15000 mPa·s, 20000 mPa·s, 25000 mPa·s, 30000 mPa·s, 50000 mPa·s, 60000 mPa·s, 70000 mPa·s, or 80000 mPa·s, but not limited thereto.
[0059] In some preferred embodiments, the viscosity of α,ω-dimethylpolydimethylsiloxane in both component A and component B is 100~60000 mPa·s; for example, 100 mPa·s, 150 mPa·s, 180 mPa·s, 200 mPa·s, 250 mPa·s, 300 mPa·s, 500 mPa·s, 600 mPa·s, 800 mPa·s, 1000 mPa·s. a·s, 1500 mPa·s, 1800 mPa·s, 2000 mPa·s, 3000 mPa·s, 4000 mPa·s, 5000 mPa·s, 8000 mPa·s, 10000 mPa·s, 20000 mPa·s, 30000 mPa·s, 40000 mPa·s, 50000 mPa·s, or 60000 mPa·s, not limited to these.
[0060] In some preferred embodiments, the first solid filler and the second solid filler are both at least one of nano-calcium carbonate, heavy calcium carbonate, aluminum hydroxide, silica powder, alumina, silica, carbon black, and titanium dioxide.
[0061] In some preferred embodiments, the viscosity of the alkoxy-terminated polydimethylsiloxane in component B is 1500~80000 mPa·s, and the end-capping method is addition or condensation; for example, 1500 mPa·s, 1600 mPa·s, 1800 mPa·s, 2000 mPa·s, 2500 mPa·s, 3000 mPa·s, 5000 mPa·s, 6000 mPa·s, 8000 mPa·s, 10000 mPa·s, 15000 mPa·s, 18000 mPa·s, 20000 mPa·s, 30000 mPa·s, 40000 mPa·s, 50000 mPa·s, 60000 mPa·s, 70000 mPa·s, or 80000 mPa·s, but not limited thereto.
[0062] In some preferred embodiments, the crosslinking agent in component B is at least one selected from alkyltrialkoxysilane, dialkyldialkoxysilane, tetraalkoxysilane, phenyltrialkoxysilane, and vinyltrialkoxysilane. As an example, the crosslinking agent is at least one selected from methyltrimethoxysilane, tetraethoxysilane, and vinyltrimethoxysilane.
[0063] In some preferred embodiments, the silane coupling agent in component B is γ-aminopropyltrialkoxysilane, γ-glycidyl alkyltrialkoxysilane, N-(β-aminoethyl)-γ-aminopropyltrialkoxysilane, N-n-butyl-3-aminopropyltrialkoxysilane, bis-[3-(trialkoxysilane)-propyl]-amine, or Evonik's Dynasylan. ® 1146. At least one of JH-AP1231 and JH-AP1234 produced by Hubei Jianghan New Materials Co., Ltd. As an example, the silane coupling agent is γ-aminopropyltrimethoxysilane or γ-aminopropyltriethoxysilane.
[0064] Specific embodiments of this application also provide a method for preparing the two-component dealcoholized silicone sealant, including the following steps: P1. At room temperature, add all the raw materials of component A into a reaction vessel equipped with stirring, heating and vacuuming functions according to the mass fractions. Turn on the stirring. After the first solid filler is completely wetted, vacuum (vacuum degree is -0.09~-0.10MPa) and continue stirring until the mixture is uniform and fine to obtain white component A.
[0065] P2. The raw materials of component B, alkoxy-terminated polydimethylsiloxane, α,ω-dimethylpolydimethylsiloxane, and the second solid filler, are added to a reaction vessel equipped with stirring, heating, and vacuum functions according to the mass ratio. Stirring is started, and after the second solid filler is completely impregnated, vacuum is applied to -0.095MPa to -0.10MPa. Stirring is continued at 110℃ to 130℃ for 2 to 4 hours. After cooling, the base adhesive is obtained. A crosslinking agent, a silane coupling agent, and a tin-containing catalyst are added to the base adhesive. The mixture is stirred for 0.5 to 1 hour at a temperature < 50℃ and a pressure of -0.095MPa to -0.10MPa to ensure uniform mixing, thus obtaining component B.
[0066] P3. Mix component A and component B evenly to obtain a two-component de-alcoholized silicone sealant.
[0067] In some preferred embodiments, the mass ratio of component A to component B is (0.5~2):1. As examples, the mass ratio of component A to component B is 0.5:1, 0.6:1, 0.7:1, 0.8:1, 0.9:1, 1:1, 1.1:1, 1.2:1, 1.3:1, 1.4:1, 1.5:1, 1.6:1, 1.7:1, 1.8:1, 1.9:1, or 2:1, and is not limited thereto.
[0068] Those skilled in the art will understand that there is no requirement to limit the order of steps P1 and P2. One of the components, A and B, can be prepared first, followed by the other component; or both components can be prepared simultaneously.
[0069] Example 1 A tin-containing catalyst has the following structural formula: .
[0070] The preparation method of this tin-containing catalyst includes the following steps: S1. Add tin tetrachloride and a monocarboxylic acid containing carbon-carbon double bonds (dodecano-11-enoic acid) into a reaction vessel at a molar ratio of 1:4.2, mix well, and obtain mixture M.
[0071] S2. Add 1% of glacial acetic acid by mass of mixture M, heat to 75°C while stirring, and keep at 75°C while stirring for 1.5 hours.
[0072] S3. Heat to 108°C and evacuate to -0.098 MPa, maintaining the vacuum until no low-boiling-point flow occurs, to obtain the tin-containing catalyst.
[0073] Example 2 A tin-containing catalyst has the following structural formula: .
[0074] The preparation method of this tin-containing catalyst includes the following steps: S1. Add monobutyltin oxide and a monocarboxylic acid containing carbon-carbon double bonds (dodecano-11-enoic acid) to a reaction vessel at a molar ratio of 1:3.15, mix well, and obtain mixture M.
[0075] S2. Add 3% glacial acetic acid by mass of mixture M, heat to 70°C while stirring, and keep at 70°C while stirring for 2 hours.
[0076] S3. Heat to 105°C and evacuate to -0.100 MPa, maintaining the vacuum until no low-boiling-point flow occurs, to obtain the tin-containing catalyst.
[0077] Example 3 A tin-containing catalyst has the following structural formula: .
[0078] The preparation method of this tin-containing catalyst includes the following steps: S1. Dioctyltin oxide and a monocarboxylic acid containing a carbon-carbon double bond (decadecano-12-enoic acid) are added to a reaction vessel at a molar ratio of 1:2.1 and mixed thoroughly to obtain mixture M.
[0079] S2. Add 5% glacial acetic acid by mass of mixture M, heat to 80°C while stirring, and keep at 80°C while stirring for 1 hour.
[0080] S3. Heat to 110°C and evacuate to -0.095 MPa, maintaining the vacuum until no low-boiling-point flow occurs, to obtain the tin-containing catalyst.
[0081] Example 4 A tin-containing catalyst has the following structural formula: .
[0082] The preparation method of this tin-containing catalyst includes the following steps: S1. Add tin tetrachloride (SnCl4) and a monocarboxylic acid containing a carbon-carbon double bond (tetradecanoic acid-13-enoic acid) to a reaction vessel at a molar ratio of 1:4.2, mix well, and obtain mixture M.
[0083] S2. Add 3% of the mass of glacial acetic acid to the mixture M, heat to 70°C while stirring, and keep stirring at 70°C for 1.5 hours.
[0084] S3. Heat to 110°C and evacuate to -0.098 MPa, maintaining the vacuum until no low-boiling-point flow occurs, to obtain the tin-containing catalyst.
[0085] Example 5 A tin-containing catalyst has the following structural formula: .
[0086] The preparation method of the tin-containing catalyst is basically the same as that in Example 4, except that the specific type of monocarboxylic acid containing carbon-carbon double bonds is different. In this example, the monocarboxylic acid containing carbon-carbon double bonds is octadec-9-enoic acid.
[0087] Example 6 A tin-containing catalyst has the following structural formula: .
[0088] The preparation method of this tin-containing catalyst differs from that of Example 3 in that: in step S1, the tin source is dodecyl tin oxide, the monocarboxylic acid containing carbon-carbon double bonds is tetradec-13-enoic acid, and the molar ratio of dodecyl tin oxide to tetradec-13-enoic acid is 1:3.15; all other aspects are the same.
[0089] Example 7 A tin-containing catalyst has the following structural formula: .
[0090] The preparation method of this tin-containing catalyst differs from that of Example 3 in that: in step S1, the tin source is dibutyltin oxide, and the monocarboxylic acid containing carbon-carbon double bonds is octadec-9-enoic acid, while the rest are the same.
[0091] Example 8 A tin-containing catalyst has the following structural formula: .
[0092] The preparation method of this tin-containing catalyst includes the following steps: S1. Diisobutyltin oxide and a monocarboxylic acid containing carbon-carbon double bonds (octadecanoic acid-9-enoic acid) are added to a reaction vessel at a molar ratio of 1:2.1 and mixed evenly to obtain mixture M.
[0093] S2. Add 3% glacial acetic acid by mass of mixture M, heat to 80°C while stirring, and keep at 80°C while stirring for 1 hour.
[0094] S3. Heat to 110°C and evacuate to -0.095 MPa, maintaining the vacuum until no low-boiling-point flow occurs, to obtain the tin-containing catalyst.
[0095] Example 9 A two-component dealcoholized silicone sealant is composed of component A and component B in a 1:1 mass ratio. Component A consists of: 100 parts of α,ω-dihydroxypolydimethylsiloxane with a viscosity of 20000 mPa·s, 10 parts of α,ω-dimethylpolydimethylsiloxane with a viscosity of 100 mPa·s, and 150 parts of heavy calcium carbonate (first solid filler). Component B consists of: 100 parts of alkoxy-terminated polydimethylsiloxane with a viscosity of 20000 mPa·s (O-FT200, prepared by addition method from Orange Sky New Materials (Guangzhou) Co., Ltd.), 30 parts of α,ω-dimethylpolydimethylsiloxane with a viscosity of 100 mPa·s, 180 parts of nano-calcium carbonate (second solid filler), 20 parts of tetraethoxysilane (crosslinking agent), 4 parts of γ-aminopropyltriethoxysilane (silane coupling agent), and 0.4 parts of the tin-containing catalyst from Example 1.
[0096] The preparation method of this two-component dealcoholized silicone sealant includes the following steps: P1. At room temperature, all the raw materials of component A are put into a reaction vessel with stirring, heating and vacuuming functions. Stirring is turned on. When the first solid filler (heavy calcium carbonate) is completely wetted, vacuum is drawn to -0.09MPa and stirring is continued for 2 hours until the mixture is uniform and fine, and white component A is obtained.
[0097] P2. Alkoxy-terminated polydimethylsiloxane, α,ω-dimethylpolydimethylsiloxane, and a second solid filler (nano-calcium carbonate) are added to a reaction vessel equipped with stirring, heating, and vacuum functions. Stirring is started, and after the nano-calcium carbonate is completely impregnated, the vacuum is drawn to -0.095 MPa, and stirring is continued at 120°C for 2 hours. After cooling, the base gel is obtained. A crosslinking agent, a silane coupling agent, and a tin-containing catalyst are added to the base gel, and the mixture is stirred for 30 minutes at a temperature <50°C (e.g., 49°C) and a pressure of -0.095 MPa to ensure uniform mixing of the reaction system, yielding component B.
[0098] P3. Mix component A and component B evenly to obtain a two-component de-alcoholized silicone sealant.
[0099] Example 10 A two-component dealcoholized silicone sealant is composed of component A and component B in a 1:1 mass ratio. Component A consists of: 100 parts of α,ω-dihydroxypolydimethylsiloxane with a viscosity of 50000 mPa·s, and 80 parts of nano-calcium carbonate (first solid filler). Component B consists of: 100 parts of alkoxy-terminated polydimethylsiloxane (O-F20000 from Orange Sky New Materials, prepared by condensation) with a viscosity of 18000 mPa·s, 5 parts of α,ω-dimethylpolydimethylsiloxane with a viscosity of 100 mPa·s, 80 parts of nano-calcium carbonate (second solid filler), 12 parts of methyltrimethoxysilane (crosslinking agent), 6 parts of γ-aminopropyltriethoxysilane (silane coupling agent), and 0.2 parts of the tin-containing catalyst from Example 2.
[0100] The preparation method of this two-component dealcoholized silicone sealant includes the following steps: P1. At room temperature, all the raw materials of component A are put into a reaction vessel with stirring, heating and vacuuming functions. Stirring is turned on. After the first solid packing is completely wetted, vacuum is drawn to -0.10MPa. Stirring is continued for 2 hours until the mixture is uniform and fine, and white component A is obtained.
[0101] P2. Alkoxy-terminated polydimethylsiloxane, α,ω-dimethylpolydimethylsiloxane, and a second solid filler are added to a reaction vessel equipped with stirring, heating, and vacuum functions. Stirring is started, and after the second solid filler is completely impregnated, the vacuum is evacuated to -0.09 MPa. Stirring continues at 110°C for 4 hours. After cooling, the base adhesive is obtained. A crosslinking agent, a silane coupling agent, and a tin-containing catalyst are added to the base adhesive. The mixture is stirred for 40 minutes at a temperature <50°C (e.g., 45°C) and a pressure of -0.09 MPa to ensure homogeneity of the reaction system, yielding component B.
[0102] P3. Mix component A and component B evenly to obtain a two-component de-alcoholized silicone sealant.
[0103] Example 11 A two-component dealcoholized silicone sealant is composed of component A and component B in a 1:1 mass ratio. Component A consists of: 100 parts of α,ω-dihydroxypolydimethylsiloxane with a viscosity of 5000 mPa·s, 16 parts of α,ω-dimethylpolydimethylsiloxane with a viscosity of 1000 mPa·s, and 120 parts of nano-calcium carbonate (first solid filler). Component B consists of: 100 parts of alkoxy-terminated polydimethylsiloxane (O-F20000 from Orange Sky New Materials, prepared by condensation) with a viscosity of 18000 mPa·s, 15 parts of α,ω-dimethylpolydimethylsiloxane with a viscosity of 1000 mPa·s, 130 parts of nano-calcium carbonate (second solid filler), 8 parts of vinyltrimethoxysilane (crosslinking agent), 8 parts of γ-aminopropyltrimethoxysilane (silane coupling agent), and 0.2 parts of the tin-containing catalyst from Example 3.
[0104] The preparation method of this two-component dealcoholized silicone sealant includes the following steps: P1. At room temperature, all the raw materials of component A are put into a reaction vessel with stirring, heating and vacuuming functions. Stirring is turned on. After the first solid packing is completely wetted, vacuum is drawn to -0.095MPa and stirring is continued for 2 hours until the mixture is uniform and fine, and white component A is obtained.
[0105] P2. Alkoxy-terminated polydimethylsiloxane, α,ω-dimethylpolydimethylsiloxane, and a second solid filler are added to a reaction vessel equipped with stirring, heating, and vacuum functions. Stirring is started, and after the second solid filler is completely impregnated, the vacuum is evacuated to -0.10 MPa. Stirring continues at 130°C for 3 hours. After cooling, the base adhesive is obtained. A crosslinking agent, a silane coupling agent, and a tin-containing catalyst are added to the base adhesive. The mixture is stirred for 60 minutes at a temperature <50°C (e.g., 40°C) and a pressure of -0.10 MPa to ensure homogeneity, yielding component B.
[0106] P3. Mix component A and component B evenly to obtain a two-component de-alcoholized silicone sealant.
[0107] Example 12 A two-component, alcohol-free silicone sealant is composed of component A and component B in a 1:1 mass ratio. Component A consists of: 100 parts of α,ω-dihydroxypolydimethylsiloxane with a viscosity of 20000 mPa·s, 5 parts of α,ω-dimethylpolydimethylsiloxane with a viscosity of 100 mPa·s, and 150 parts of heavy calcium carbonate (first solid filler). Component B consists of: 100 parts of alkoxy-terminated polydimethylsiloxane (O-F5000 from Orange Sky New Materials, prepared by condensation) with a viscosity of 4500 mPa·s, 10 parts of α,ω-dimethylpolydimethylsiloxane with a viscosity of 60000 mPa·s, 150 parts of nano-calcium carbonate (second solid filler), 5 parts of tetraethoxysilane (crosslinking agent), and 4 parts of Dynasylan. ® 1146 (silane coupling agent), 0.6 parts of the tin-containing catalyst in Example 1.
[0108] The preparation method of this two-component dealcoholized silicone sealant includes the following steps: P1. At room temperature, all the raw materials of component A are put into a reaction vessel with stirring, heating and vacuuming functions. Stirring is turned on. After the first solid filler is completely wetted, vacuum is drawn to -0.09MPa and stirring is continued for 2 hours until the mixture is uniform and fine, and white component A is obtained.
[0109] P2. Alkoxy-terminated polydimethylsiloxane, α,ω-dimethylpolydimethylsiloxane, and a second solid filler are added to a reaction vessel equipped with stirring, heating, and vacuum functions. Stirring is started, and after the second solid filler is completely impregnated, the vacuum is evacuated to -0.095 MPa. Stirring continues at 120°C for 2 hours, and the base gel is obtained after cooling. A crosslinking agent, a silane coupling agent, and a tin-containing catalyst are added to the base gel, and the mixture is stirred for 40 minutes at a temperature <50°C (e.g., 48°C) and a pressure of -0.095 MPa to ensure uniform mixing, thus obtaining component B.
[0110] P3. Mix component A and component B at a mass ratio of 1:1 to obtain a two-component de-alcoholized silicone sealant.
[0111] Example 13 The only difference between the two-component de-alcoholized silicone sealant provided in this embodiment and the two-component de-alcoholized silicone sealant in Example 11 is that the tin-containing catalyst used in Example 11 is replaced with the tin-containing catalyst in Example 4.
[0112] Example 14 The only difference between the two-component de-alcoholized silicone sealant provided in this embodiment and the two-component de-alcoholized silicone sealant in Example 11 is that the tin-containing catalyst used in Example 11 is replaced with the tin-containing catalyst in Example 5.
[0113] Example 15 The only difference between the two-component de-alcoholized silicone sealant provided in this embodiment and the two-component de-alcoholized silicone sealant in Example 11 is that the tin-containing catalyst used in Example 11 is replaced with the tin-containing catalyst in Example 6.
[0114] Example 16 The only difference between the two-component de-alcoholized silicone sealant provided in this embodiment and the two-component de-alcoholized silicone sealant in Example 11 is that the tin-containing catalyst used in Example 11 is replaced with the tin-containing catalyst in Example 7.
[0115] Example 17 The only difference between the two-component de-alcoholized silicone sealant provided in this embodiment and the two-component de-alcoholized silicone sealant in Example 11 is that the tin-containing catalyst used in Example 11 is replaced with the tin-containing catalyst in Example 8.
[0116] Comparative Example 1 The only difference between the two-component de-alcoholized silicone sealant provided in this comparative example and the two-component de-alcoholized silicone sealant of Example 9 in terms of composition and preparation method is that the tin-containing catalyst used in Example 9 is replaced with dibutyltin dilaurate.
[0117] Comparative Example 2 The only difference between the two-component de-alcoholized silicone sealant provided in this comparative example and the two-component de-alcoholized silicone sealant of Example 10 in terms of composition and preparation method is that the tin-containing catalyst used in Example 10 is replaced with dibutyltin diacetate.
[0118] Comparative Example 3 The only difference between the two-component de-alcoholized silicone sealant provided in this comparative example and the two-component de-alcoholized silicone sealant of Example 11 in terms of composition and preparation method is that the tin-containing catalyst used in Example 11 is replaced with acetylacetone chelated dibutyltin.
[0119] Sealant performance test The performance of the sealants prepared in Examples 9-17 and Comparative Examples 1-3 was tested according to the methods in GB / T 29595-2013 "Silicone Rubber Sealants for Ground-mounted Photovoltaic Modules". The test results are shown in Table 1. Immediately after preparation, the initial surface drying time (denoted as "Surface Drying Time I") and preliminary curing time (denoted as "Cure Time I, i.e., the pot life specified in GB / T 29595-2013) were tested. The sealant was then used to bond substrates such as anodized aluminum oxide and glass. After complete curing, its tensile strength (denoted as "Tensile Strength I"), elongation at break (denoted as "Elongation at Break I"), shear strength of anodized aluminum oxide against glass (denoted as "Shear Strength I"), and mode of failure were tested. Components A and B were heated to 70°C and maintained for 7 days, then mixed uniformly to prepare a sealant. Its surface drying time (denoted as "Surface Drying Time II") and preliminary curing time (denoted as "Cure Time II") were then tested. The sealants prepared in Examples 4-7 and Comparative Examples 1-3 were sealed and stored at room temperature for 9 months. Then, their surface drying time (referred to as "Surface Drying Time III") and initial curing time (referred to as "Cure Time III") were tested. The sealants were then used to bond substrates such as anodized aluminum and glass. After complete curing, their tensile strength (referred to as "Tensile Strength II"), elongation at break (referred to as "Elongation at Break II"), shear strength of anodized aluminum against glass (referred to as "Shear Strength II"), and failure mode were tested.
[0120] Table 1 Performance test results of the sealant
[0121] In Table 1, " / " indicates that no experimental data was available (because the sealant cannot be cured, the corresponding experimental data could not be measured). As can be seen from the data in Table 1, the two-component de-alcoholized silicone sealant provided by this invention has advantages such as fast curing speed, good mechanical properties, strong adhesion, and long storage time compared to the sealant prepared in the comparative example. It can meet the needs of high-precision, continuous, and large-scale production in industries such as new energy and electronics.
[0122] The embodiments described above are merely preferred embodiments of this application and are not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by anyone skilled in the art. Any simple equivalent changes and modifications made based on the scope of protection claimed in this application and the content of the specification should be included within the scope of protection of this application.
Claims
1. A tin-containing catalyst, characterized in that, The structural formula of the tin-containing catalyst is as follows: In this context, R is a C4-C12 alkyl group; when x=0 or 1, R' is a C11-C17 alkenyl group; when x=2, R' is a C13-C17 alkenyl group.
2. The tin-containing catalyst according to claim 1, characterized in that, x = 0 or 1.
3. The method for preparing the tin-containing catalyst according to claim 1 or 2, characterized in that, Includes the following steps: S1. Add alkyl tin oxide or tin tetrachloride to a monocarboxylic acid containing a carbon-carbon double bond in a molar ratio of 1:(4.2-1.05x) and mix thoroughly to obtain mixture M; S2. Add 1% to 5% of glacial acetic acid by mass of the mixture M, heat to 70°C to 80°C while stirring, and keep warm and stirring for 1 to 2 hours; S3. After the heat preservation is completed, the temperature is raised to 105℃~110℃ and vacuumed until no low-boiling-point flow occurs, thus obtaining the tin-containing catalyst.
4. A two-component, alcohol-free silicone sealant, characterized in that, It includes component A and component B; component A consists of the following components: 100 parts of α,ω-dihydroxypolydimethylsiloxane, 0-30 parts of α,ω-dimethylpolydimethylsiloxane, and 30-180 parts of a first solid filler; component B consists of the following components: 100 parts of alkoxy-terminated polydimethylsiloxane, 0-100 parts of α,ω-dimethylpolydimethylsiloxane, 30-300 parts of a second solid filler, 3-30 parts of a crosslinking agent, 2-10 parts of a silane coupling agent, and 0.05-2 parts of the tin-containing catalyst according to claim 1 or 2.
5. The two-component de-alcoholized silicone sealant according to claim 4, characterized in that, The viscosity of α,ω-dihydroxypolydimethylsiloxane in component A is 1500~100000 mPa·s; or / and the first solid filler is at least one of nano-calcium carbonate, heavy calcium carbonate, aluminum hydroxide, silica powder, alumina, silica, carbon black, and titanium dioxide.
6. The two-component de-alcoholized silicone sealant according to claim 4, characterized in that, The viscosity of both α,ω-dimethylpolydimethylsiloxane in component A and α,ω-dimethylpolydimethylsiloxane in component B is 100~60000 mPa·s.
7. The two-component de-alcoholized silicone sealant according to claim 4, characterized in that, The viscosity of the alkoxy-terminated polydimethylsiloxane in component B is 1500~80000 mPa·s; or / and the second solid filler is at least one of nano-calcium carbonate, heavy calcium carbonate, aluminum hydroxide, silica powder, alumina, silica, carbon black, and titanium dioxide.
8. The two-component de-alcoholized silicone sealant according to claim 4, characterized in that, The crosslinking agent in component B is at least one of alkyltrialkoxysilane, dialkyldialkoxysilane, tetraalkoxysilane, phenyltrialkoxysilane, and vinyltrialkoxysilane; or / and the silane coupling agent in component B is γ-aminopropyltrialkoxysilane, γ-glycidyl alkyltrialkoxysilane, N-(β-aminoethyl)-γ-aminopropyltrialkoxysilane, N-n-butyl-3-aminopropyltrialkoxysilane, bis-[3-(trialkoxysilane)-propyl]-amine, or Dynasylan. ® At least one of 1146, JH-AP1231, and JH-AP1234.
9. The method for preparing the two-component dealcoholized silicone sealant according to any one of claims 4 to 8, characterized in that, The process includes the following steps: Adding the raw materials of component A into a reaction vessel, starting stirring, and after the first solid filler is completely impregnated, applying a vacuum and stirring until the mixture is uniform and fine to obtain component A; adding the alkoxy-terminated polydimethylsiloxane, α,ω-dimethylpolydimethylsiloxane, and the second solid filler from component B into the reaction vessel, starting stirring, and after the second solid filler is completely impregnated, applying a vacuum, and continuing stirring at 110℃~130℃ for 2~4 hours, and cooling to obtain the base adhesive; adding a crosslinking agent, a silane coupling agent, and the tin-containing catalyst to the base adhesive, and stirring until uniformly mixed under conditions of temperature <50℃ and vacuum to obtain component B; mixing component A and component B uniformly to obtain the two-component dealcoholized silicone sealant.
10. The preparation method according to claim 9, characterized in that, The mass ratio of component A to component B is (0.5~2):1.