Single-component dealcoholization type room temperature curing silicone rubber and preparation method thereof

Abstract

The invention belongs to the technical field of silicone rubber, and particularly relates to single-component dealcoholization type room temperature curing silicone rubber with low density and high glowing filament flammability index and a preparation method of the single-component dealcoholization type room temperature curing silicone rubber. The single-component room temperature curing silicone rubber is prepared from alkoxy-terminated polydimethylsiloxane, hydrophobic white carbon black, a heat-resistant filler, a pigment, a cross-linking agent, a tackifier, a catalyst and a hydroxyl scavenger as raw materials through powder drying, mixing, grinding, drying and glue preparation. The glowing filament flammability index (GWFI) of the single-component dealcoholization type room temperature curing silicone rubber is 850 DEG C / 3mm, the single-component dealcoholization type room temperature curing silicone rubber is halogen-free, environment-friendly, neutral and corrosion-free, the density is smaller than or equal to 1.1 g / cm < 3 >, the tensile strength is larger than or equal to 2.0 MPa, the elongation at break is larger than or equal to 200%, the shear strength is larger than or equal to 2.0 MPa, and the single-component dealcoholization type room temperature curing silicone rubber can be used for elastic bonding, fixing, insulation and sealing of various electronic components and electrical equipment with high glowing filament requirements.

Description

Technical Field

[0001] This invention belongs to the field of single-component room temperature curing silicone rubber technology, specifically relating to a low-density, high glow wire flammability index single-component de-alcoholized room temperature curing silicone rubber that can be used for sealing and bonding of electrical and electronic products, and its preparation method. Background Technology

[0002] Single-component alcohol-free room temperature curing rubber is widely used for elastic bonding, fixing, insulation, and sealing of various electronic components and electrical equipment due to its excellent electrical insulation properties, excellent adhesion, good mechanical properties, and neutral and non-corrosive nature.

[0003] In recent years, with the frequent occurrence of fires involving household appliances during use, it is necessary to screen materials that meet safety requirements through the glow wire test to reduce the risk of fires caused by overheating, protect the lives and property of end users, and meet market access compliance requirements. The glow wire test is an experimental method for evaluating the flammability and combustion behavior of materials under the influence of a specific heat source (such as a glow wire).

[0004] Simulation techniques assess the fire hazard caused by thermal stress from heat sources such as glowing elements or overloaded resistors over a short period of time. The glow-wire flammability index (GWFI) is the highest temperature of the test material measured using the standardized test method of GB / T 5169.12, under the following conditions: a) it does not ignite, or if it does ignite, it extinguishes within 30 seconds after the glow wire is removed and is not completely burned; and b) if there are molten drips, they do not ignite the packaging paper.

[0005] CN112143162B discloses an ABS composite material and its preparation method. The resulting ABS composite material has a GWIT greater than 775℃ and good stability, meeting safety requirements. This can unlock the application of flame-retardant ABS materials in heaters and around electrical components.

[0006] CN116715943B discloses a method for producing flame-retardant polycarbonate with a high glow wire flammability index. Using melamine-formaldehyde resin sulfonate as a flame retardant significantly reduces material costs. Melamine-formaldehyde resin sulfonate generates a large amount of inert gas during combustion, which not only reduces the oxygen concentration in the gas phase, but also provides high-efficiency flame retardant properties, good impact resistance, and electrical properties. It can be applied in many fields such as electronics, electrical appliances, and automobiles, and meets the requirements for socket production. It also exhibits good processing fluidity and achieves V-0 flame retardancy and a glow wire ignition temperature of 960℃ with a relatively low amount of flame retardant added. Summary of the Invention

[0007] The purpose of this invention is to further improve the glow wire resistance of single-component room temperature curing silicone rubber used for bonding and sealing electrical and electronic products. It provides a low-density, high glow wire flammability index (GWFI) single-component alcohol-based room temperature curing silicone rubber with a GWFI of 850℃ / 3mm, halogen-free and environmentally friendly, neutral and non-corrosive, and a density ≤1.1g / cm³. 3 With tensile strength ≥2.0MPa, elongation at break ≥200%, and shear strength ≥2.0MPa, it can be used for elastic bonding, fixing, insulation, and sealing of various electronic components and electrical equipment that require high glow wire.

[0008] This invention provides a one-component de-alcoholized room temperature curing silicone rubber, the raw materials of which include the following components in parts by weight: 50-90 parts of alkoxy-terminated polydimethylsiloxane, 5-15 parts of hydrophobic silica, 1-10 parts of heat-resistant filler, 0-10 parts of pigment, 1-10 parts of crosslinking agent, 0.5-5 parts of tackifier, 0.1-5 parts of catalyst, and 0.5-5 parts of hydroxyl scavenger.

[0009] Preferably, in the above-mentioned one-component alcohol-free room temperature curing silicone rubber, the alkoxy-terminated polydimethylsiloxane (commonly known as end-capped 107 adhesive) is modified by end-capping with either hydroxyl-terminated polydimethylsiloxane (107 adhesive) or vinyl-terminated polydimethylsiloxane (vinyl silicone oil). The above-mentioned alkoxy-terminated modification synthesis method is known and can be obtained through patents such as US4962174 and US 4731411. The alkoxy-terminated polydimethylsiloxane can also be directly purchased, such as the end-capped 107 adhesive J-200 from Jiangsu Kexing Co., Ltd.

[0010] Preferably, in the above-mentioned one-component de-alcoholized room temperature curing silicone rubber, the alkoxy-terminated polydimethylsiloxane has the structure shown in formula (I):

[0011] (I)

[0012] Each R1 is independently C 1-4 Alkoxy groups, each R2 independently has a C 1-4 Alkyl or C 1-4 Alkoxy groups, each Z is independently O or C. 1-4 Alkylene or a group represented by formula (II), where m is any value from 200 to 5000;

[0013] (II).

[0014] Preferably, in the above-mentioned one-component alcohol-free room temperature curing silicone rubber, each R1 is independently methoxy, ethoxy, or propoxy. More preferably, each R1 is independently methoxy.

[0015] Preferably, in the above-mentioned single-component de-alcoholized room temperature curing silicone rubber, each R2 is independently methoxylated.

[0016] Preferably, in the above-mentioned single-component alcohol-free room temperature curing silicone rubber, each Z is independently O, ethylene, propylene, or a group represented by formula (II).

[0017] Preferably, in the above-mentioned single-component de-alcoholized room temperature curing silicone rubber, m is any value from 200 to 1500.

[0018] Preferably, in the above-mentioned one-component alcohol-free room temperature curing silicone rubber, the alkoxy-terminated polydimethylsiloxane has a viscosity of 100 mPa·s to 300,000 mPa·s at 25°C. More preferably, it is 600 mPa·s to 100,000 mPa·s.

[0019] Preferably, in the above-mentioned single-component, alcohol-free, room-temperature curing silicone rubber, the hydrophobic silica is obtained by modifying silica through a hydrophobic surface treatment. The specific surface area of ​​the hydrophobic silica is 150~400 m² / g. 2 / g. Preferably 150~250m 2 / g. The hydrophobic surface treatment is performed, for example, using dimethyldichlorosilane, hexamethyldihexamethyldisilazane, octamethylcyclotetrasiloxane, or silicone oil by conventional methods. The hydrophobic silica is also readily available, such as Evonik Chemical's hydrophobic silica R974, 812S, and R106.

[0020] Preferably, in the above-mentioned single-component de-alcoholized room temperature curing silicone rubber, the heat-resistant filler is at least one of alumina, cerium oxide, iron oxide, titanium oxide, and zinc oxide.

[0021] Preferably, in the above-mentioned single-component alcohol-free room temperature curing silicone rubber, the pigment is at least one of iron oxide, titanium oxide, carbon black, iron yellow, and iron blue.

[0022] Preferably, in the above-mentioned single-component de-alcoholized room temperature curing silicone rubber, the crosslinking agent is at least one of methyltrimethoxysilane, methyltriethoxysilane, and vinyltrimethoxysilane.

[0023] Preferably, in the above-mentioned single-component alcohol-free room temperature curing silicone rubber, the tackifier (coupling agent) is selected from at least one of silane coupling agents containing amino groups, silane coupling agents containing epoxy groups, or coupling agents containing silicon-nitrogen heterocyclic structures.

[0024] Furthermore, in the aforementioned one-component, alcohol-free, room-temperature curing silicone rubber, the silane coupling agent containing amino groups is at least one of 3-aminopropyltriethoxysilane, N-(2-aminoethyl-3-aminopropyl)trimethoxysilane, and diethylenetriaminepropyltrimethoxysilane. Examples include Momentive's 3-aminopropyltriethoxysilane Silquest A-1100, N-(2-aminoethyl-3-aminopropyl)trimethoxysilane A-1120, and diethylenetriaminepropyltrimethoxysilane A-1130.

[0025] Furthermore, in the aforementioned one-component, alcohol-free, room-temperature curing silicone rubber, the epoxy-containing silane coupling agent is at least one of 3-(2,3-epoxypropoxy)propyltrimethoxysilane and 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane. Examples include Momentive's 3-(2,3-epoxypropoxy)propyltrimethoxysilane Silquest A-187 and 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane Silquest A-186.

[0026] Furthermore, in the aforementioned one-component, alcohol-free, room-temperature curing silicone rubber, the coupling agent containing a silicon-nitrogen heterocyclic structure is tris(3-trimethoxysilylpropyl)isocyanurate. For example, Momentive's tris(3-trimethoxysilylpropyl)isocyanurate Silquest A-link 597.

[0027] Preferably, in the above-mentioned single-component alcohol-free room temperature curing silicone rubber, the catalyst is a titanium-containing or tin-containing catalyst.

[0028] Furthermore, in the aforementioned one-component dealcohol-type room temperature curing silicone rubber, the titanium-containing catalyst is selected from at least one of tetrabutyl titanate, tert-butyl titanate, isopropyl titanate, or titanium chelates obtained by reacting them with compounds containing a β-diketone structure (e.g., ethyl acetoacetate). For example, a reaction chelate of isopropyl titanate and ethyl acetoacetate (e.g., Dorf Ketal's Tyzor® 726).

[0029] Furthermore, in the above-mentioned single-component alcohol-free room temperature curing silicone rubber, the tin-containing catalyst is selected from at least one of dibutyltin dilaurate, dibutyltin diacetate, and stannous octoate.

[0030] Preferably, in the above-mentioned alcohol-free room temperature curing silicone rubber, the hydroxyl scavenger is at least one of amino-functionalized silanes (e.g., N,N-diethylaminosilane), silazanes (e.g., hexamethyldisilazane), trialkoxysilylpropionate (e.g., methyl trimethoxysilylpropionate), trialkylsilylacetate (e.g., butyl triethylsilylacetate), and isocyanate-based siloxysilanes (e.g., 3-isocyanate-based propyltrimethoxysilane).

[0031] Furthermore, in the above-mentioned alcohol-free room temperature curing silicone rubber, the hydroxyl scavenger is at least one of N,N-diethylaminosilane, hexamethyldisilazane, methyl trimethoxysilylpropionate, butyl triethylsilylacetate, and 3-isocyanate propyltrimethoxysilane.

[0032] Furthermore, in the above-mentioned alcohol-free room temperature curing silicone rubber, the hydroxyl scavenger is hexamethyldisilazane.

[0033] This invention also provides a method for preparing the above-mentioned single-component alcohol-free room temperature curing silicone rubber. The preparation method includes the following steps: first, drying hydrophobic silica, heat-resistant filler, and pigment separately or in combination; then mixing alkoxy-terminated polydimethylsiloxane with hydrophobic silica, heat-resistant filler, and pigment, stirring and kneading to obtain a base compound; further grinding and vacuum drying the base compound; then adding a crosslinking agent and mixing, followed by adding a tackifier, catalyst, and hydroxyl scavenger and mixing, degassing treatment, and packaging.

[0034] Furthermore, the preparation method of the above-mentioned one-component alcohol-de-alcohol type room temperature curing silicone rubber includes the following steps:

[0035] A. Powder drying process: Dry the hydrophobic silica, heat-resistant filler, and pigment separately or in combination (e.g., at 130℃~150℃ for 3h~6h).

[0036] B. Mixing process: Mix alkoxy-terminated polydimethylsiloxane, hydrophobic silica, heat-resistant filler and pigment, and stir and knead (for example, 10-30 minutes) to obtain the base compound;

[0037] C. Grinding process: Grind the base adhesive (e.g., 1-2 times);

[0038] D. Drying process: Heat and stir the base rubber compound (e.g., for 30-60 minutes), then vacuum dry (e.g., start timing when the material temperature reaches 100℃, maintain the material temperature at 100-120℃ and the vacuum degree at no less than -0.08MPa, and vacuum stir and dry for 1-2 hours).

[0039] E. Adhesive preparation process: First, add the crosslinking agent to the base adhesive and stir (e.g., 10-20 minutes). Then add the tackifier, catalyst, and hydroxyl scavenger and continue stirring (e.g., 10-20 minutes). Then degas under vacuum (e.g., vacuum degree not lower than -0.08MPa) (e.g., 20-30 minutes), filter and package to obtain the finished product.

[0040] Beneficial effects of this invention:

[0041] This invention modifies polydimethylsiloxane by alkoxy-termining, and uses silica as a reinforcing filler through hydrophobic surface treatment to reduce the number of silanol groups on the silica surface. Simultaneously, a hydroxyl scavenger is added to reduce the hydroxyl groups in the base polymer and filler, improving the heat resistance of the adhesive. The addition of heat-resistant filler utilizes its high-temperature oxidation properties to further enhance the adhesive's heat resistance. Through the synergistic effect of low hydroxyl content and heat-resistant filler, a single-component room-temperature curing silicone rubber exhibits unexpected heat-wire resistance. Furthermore, the silicone rubber formulation contains only surface-modified silica reinforcing filler and a small amount of heat-resistant filler, with a low density and good mechanical properties, avoiding the defects of high density and poor toughness caused by large amounts of flame-retardant filler.

[0042] The low-density, high glow filament flammability index (GWFI) single-component, alcohol-free, room-temperature curing silicone rubber obtained by this invention has a GWFI of 850℃ / 3mm, is halogen-free and environmentally friendly, neutral and non-corrosive, and has a density ≤1.1g / cm³. 3 With tensile strength ≥2.0MPa, elongation at break ≥200%, and shear strength ≥2.0MPa, it can be used for elastic bonding, fixing, insulation, and sealing of various electronic components and electrical equipment that require high glow wire. Detailed Implementation

[0043] The present invention will be further described below with reference to specific embodiments, and the specific implementation of the present invention will be described in detail through the embodiments.

[0044] The other raw materials used in the embodiments and comparative examples of this invention are as follows:

[0045] A1: α,ω-trimethoxysilyl-terminated polydimethylsiloxane, end-capping 107 adhesive, grade: J-200, viscosity at 25℃: 20000 mPa.s, Jiangsu Kexing Co., Ltd., its structural formula is (MeO)3SiO(Me2SiO). m Si(MeO)3 (m approximately 900), a trimethoxysilane-terminated polydimethylsiloxane.

[0046] A2: α,ω-dihydroxypolydimethylsiloxane, 107 adhesive, grade RTV-107-2, viscosity at 25℃ 20000 mPa.s, manufactured by Hoshine Silicon Industry Co., Ltd., its structural formula is HO(Me2SiO). m H (m is approximately 900), a hydroxyl-terminated polydimethylsiloxane.

[0047] B1: Fumed silica treated with hexamethyldihexamethyldisilazane, AEROSIL® R 812 S, with a specific surface area of ​​195~245 m². 2 / g, Evonik Chemicals.

[0048] B2: Fumed silica treated with dimethyldichlorosilane, AEROSIL® R 974, with a specific surface area of ​​150~190 m². 2 / g, Evonik Chemicals.

[0049] B3: Untreated hydrophilic fumed silica, AEROSIL® 200, with a specific surface area of ​​175~225 m². 2 / g, Evonik Chemicals.

[0050] C1: Cerium oxide, Huizhou Ruier.

[0051] C2: Iron oxide, Lanxess, Germany.

[0052] C3: Aluminum oxide, from Daehan, South Korea.

[0053] C4: Zinc oxide, Qingyun Hongsheng.

[0054] C5: Titanium oxide, Evonik Chemicals.

[0055] D: Stearic acid-treated activated calcium carbonate, oil absorption value 18-28 g / 100g, Qianxian Haifeng Nanomaterials Co., Ltd.

[0056] E1: Decabromodiphenyl ethane, Shouguang Puer.

[0057] E2: Aluminum hydroxide, China Aluminum Zhongzhou.

[0058] F: Carbon black, Dandong inkstone.

[0059] G: Crosslinking agent for conventional alcohol-free silicone rubber, methyltrimethoxysilane, JH-N311, Jianghan, Jingzhou, Hubei.

[0060] H: Tackifier, aminopropyltriethoxysilane, Silquest A-1100, Momentive Advanced Materials Group.

[0061] I: Hydroxyl scavenger, hexamethyldisilazane, Sichuan Jiabi.

[0062] J: Catalyst, dibutyltin dilaurate, Jianyi Chemical.

[0063] The testing method of this invention is as follows:

[0064] (1) Glow-wire flammability index (GWFI) test method: GBT5169.12 Fire hazard test for electrical and electronic products - Part 12 Basic test methods for glow wire / hot wire - Test method for glow wire flammability of materials.

[0065] (2) Density test method: GB / T 4472 Determination of density and relative density of chemical products.

[0066] (3) Test methods for tensile strength and elongation at break: GB / T 528 Determination of tensile stress-strain properties of vulcanized rubber or thermoplastic rubber.

[0067] (4) Shear strength test method: GB / T 7124 Determination of tensile shear strength of adhesives (rigid material to rigid material).

[0068] The preparation methods of this invention are all as follows:

[0069] The powder was pre-dried in a 150°C oven for 3 hours. The methoxy-terminated polydimethylsiloxane and the powder were added sequentially to a biaxial kneader and kneaded for 20 minutes to obtain the base compound. The base compound was then ground once in a three-roll mill. The base compound was returned to the kneader and heated and stirred for 30 minutes. It was then vacuum dried for 1 hour at a set temperature of 120°C and a vacuum degree of -0.09MPa. The base compound was then added to a planetary mixer. The crosslinking agent was added first and stirred for 15 minutes. Then the tackifier, catalyst, and hydroxyl scavenger were added and stirred at high speed for 15 minutes. Finally, the mixture was degassed under a vacuum degree of -0.09MPa for 20 minutes, filtered, and packaged to obtain the finished product.

[0070] Table 1 shows the proportions of each raw material used in the examples and comparative examples, all by weight.

[0071] Table 1. Formulations and performance of the examples and comparative examples

[0072] As shown in Table 1, the comprehensive performance of the single-component, alcohol-free, room-temperature curing silicone rubber of this invention is as follows: glow wire flammability index (GWFI) of 850℃ / 3mm, halogen-free and environmentally friendly, neutral and non-corrosive, and density ≤1.1g / cm³. 3 With tensile strength ≥2.0MPa, elongation at break ≥200%, and shear strength ≥2.0MPa, it can be used for elastic bonding, fixing, insulation, and sealing of various electronic components and electrical equipment that require high glow wire.

[0073] The glow wire flammability index (GWFI) of the product obtained in Example 1 is 850℃ / 3mm, it is halogen-free and environmentally friendly, and its density is 1.06g / cm³. 3The tensile strength was 2.5 MPa, the elongation at break was 250%, and the shear strength was 2.3 MPa. Comparative Example 1, based on Example 1, replaced the alkoxy-terminated polydimethylsiloxane with hydroxyl-terminated polydimethylsiloxane, achieving a glow wire flammability index (GWFI) of 700°C / 3 mm. Comparative Example 2, based on Example 1, replaced the untreated hydrophilic silica with surface-modified hydrophobic silica, achieving a glow wire flammability index (GWFI) of 700°C / 3 mm. Comparative Example 3, based on Example 1, removed the hydroxyl scavenger hexamethyldisilazane, achieving a glow wire flammability index (GWFI) of 700°C / 3 mm. Comparative Example 4, based on Example 1, removed the heat-resistant filler, achieving a glow wire flammability index (GWFI) of 700°C / 3 mm. Therefore, under the synergistic effect of low hydroxyl content and heat-resistant filler, the single-component room-temperature curing silicone rubber in Example 1 exhibited unexpected glow wire resistance, with the glow wire flammability index (GWFI) increasing from 700°C / 3mm to 850°C / 3mm. Comparative Example 5, using hydroxyl-terminated polydimethylsiloxane, reinforcing filler calcium carbonate, flame-retardant filler decabromodiphenyl ethane, and aluminum hydroxide, achieved a glow wire flammability index (GWFI) of 800°C / 3mm and a density of 1.3 g / cm³. 3 It has a tensile strength of 1.8 MPa, an elongation at break of 180%, a shear strength of 1.5 MPa, a relatively high density, poor toughness, contains halogens, and does not meet regulatory requirements.

[0074] The above embodiments are only used to illustrate and not limit the technical solutions of the present invention. Although the above embodiments have described the present invention in detail, those skilled in the art should understand that modifications or equivalent substitutions can be made to the present invention, but any modifications and partial substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of the claims of the present invention.

Claims

1. A one-component, alcohol-free, room-temperature curing silicone rubber, characterized in that: Its raw materials include the following components in parts by weight: 50-90 parts of alkoxy-terminated polydimethylsiloxane, 5-15 parts of hydrophobic silica, 1-10 parts of heat-resistant filler, 0-10 parts of pigment, 1-10 parts of crosslinking agent, 0.5-5 parts of tackifier, 0.1-5 parts of catalyst, and 0.5-5 parts of hydroxyl scavenger.

2. The single-component, alcohol-free, room-temperature curing silicone rubber according to claim 1, characterized in that: The alkoxy-terminated polydimethylsiloxane is prepared by end-capping and modification of hydroxyl-terminated polydimethylsiloxane or vinyl-terminated polydimethylsiloxane. Furthermore, the alkoxy-terminated polydimethylsiloxane has the structure shown in formula (I): (I) Each R1 is independently C 1-4 Alkoxy groups, each R2 independently has a C 1-4 Alkyl or C 1-4 Alkoxy groups, each Z is independently O or C. 1-4 Alkylene or a group represented by formula (II), where m is any value from 200 to 5000; (II); Preferably, each R1 is independently methoxy, ethoxy, or propoxy; more preferably, each R1 is independently methoxy. Preferably, each R2 is independently methoxylated; Preferably, each Z is independently O, ethylene, propylene, or a group of formula (II); Preferably, m is any value between 200 and 1500; Furthermore, the viscosity of the alkoxy-terminated polydimethylsiloxane at 25°C is 100 mPa·s to 300,000 mPa·s; preferably 600 mPa·s to 100,000 mPa·s.

3. The single-component, alcohol-free, room-temperature curing silicone rubber according to claim 1 or 2, characterized in that: The hydrophobic silica is obtained by modifying silica through hydrophobic surface treatment; preferably, the specific surface area of ​​the hydrophobic silica is 150~400m². 2 / g; more preferably, a specific surface area of ​​150~250m² 2 / g.

4. The single-component, alcohol-free, room-temperature curing silicone rubber according to any one of claims 1-3, characterized in that: The heat-resistant filler is at least one of alumina, cerium oxide, iron oxide, titanium oxide, and zinc oxide.

5. The single-component, alcohol-free, room-temperature curing silicone rubber according to any one of claims 1-4, characterized in that: The pigment is at least one of iron oxide, titanium oxide, carbon black, iron yellow, and iron blue.

6. The single-component, alcohol-free, room-temperature curing silicone rubber according to any one of claims 1-5, characterized in that: The crosslinking agent is at least one of methyltrimethoxysilane, methyltriethoxysilane, and vinyltrimethoxysilane.

7. The single-component, alcohol-free, room-temperature curing silicone rubber according to any one of claims 1-6, characterized in that: The tackifier is selected from at least one of silane coupling agents containing amino groups, silane coupling agents containing epoxy groups, or coupling agents containing silicon-nitrogen heterocyclic structures; preferably, the silane coupling agent containing amino groups is at least one of 3-aminopropyltriethoxysilane, N-(2-aminoethyl-3-aminopropyl)trimethoxysilane, and diethylenetriaminopropyltrimethoxysilane; the silane coupling agent containing epoxy groups is at least one of 3-(2,3-epoxypropoxy)propyltrimethoxysilane and 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane; and the coupling agent containing silicon-nitrogen heterocyclic structures is tris(3-trimethoxysilylpropyl)isocyanurate.

8. The single-component, alcohol-free, room-temperature curing silicone rubber according to any one of claims 1-7, characterized in that: The catalyst is a titanium-containing or tin-containing catalyst; preferably, the titanium-containing catalyst is selected from at least one of tetrabutyl titanate, tert-butyl titanate, isopropyl titanate, or titanium chelates obtained by reacting them with compounds containing β-diketone structures; the tin-containing catalyst is selected from at least one of dibutyltin dilaurate, dibutyltin diacetate, and stannous octoate.

9. The single-component, alcohol-free, room-temperature curing silicone rubber according to any one of claims 1-8, characterized in that: The hydroxyl scavenger is at least one of amino-functionalized silane, silazane, trialkoxysilylpropionate, trialkylsilylacetate, and isocyanate-based alkylsiloxysilane; the hydroxyl scavenger is at least one of N,N-diethylaminosilane, hexamethyldisilazane, methyl trimethoxysilylpropionate, butyl triethylsilylacetate, and 3-isocyanate-based propyltrimethoxysilane; more preferably, the hydroxyl scavenger is hexamethyldisilazane.

10. The method for preparing the single-component, alcohol-free, room-temperature curing silicone rubber according to any one of claims 1-9, characterized in that: Includes the following steps: First, dry the hydrophobic silica, heat-resistant filler, and pigment separately or in combination. Then, mix the alkoxy-terminated polydimethylsiloxane with the hydrophobic silica, heat-resistant filler, and pigment, stir and knead to obtain the base compound. Grind and vacuum dry the base compound. Then, add a crosslinking agent and mix, followed by a tackifier, catalyst, and hydroxyl scavenger. After degassing, package the product.

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