A room temperature in situ formed foamed silicone gel

Abstract

This invention belongs to the field of organosilicon modification technology, and relates to a room-temperature in-situ foamed silicone, comprising the following components in parts by weight: Component A: 20-50 parts hydroxyl silicone oil, 15-50 parts vinyl silicone oil, 5-20 parts vinyl MQ resin, 20-30 parts aluminum hydroxide, 1-10 parts hydrogen-containing silicone oil, 1-10 parts phenyltris(dimethylsiloxane)silane, 1-10 parts silica, and 0.005-0.1 parts inhibitor; Component B: 20-80 parts vinyl silicone oil, 20-30 parts aluminum hydroxide, 1-10 parts modified silicone oil, 1-10 parts silica, 0.05-0.5 parts Pt catalyst, 0.05-0.5 parts Ti catalyst, and 0.05-0.1 parts black color paste. This invention improves the adhesion between the foamed silicone and the interface through the addition of modified silicone oil; the addition of phenyltris(dimethylsiloxane)silane improves the compression resilience of the formed dense microporous colloid.

Description

Technical Field

[0001] This invention belongs to the field of organosilicon modification technology, and particularly relates to a room temperature in-situ foamed silicone. Background Technology

[0002] In the lightweighting industry, traditional foamed gaskets cannot meet the sealing requirements of various shapes, and custom-made models according to different shape requirements are very costly. Furthermore, some materials cannot be baked at high temperatures, making room temperature in-situ foamed gaskets a new favorite.

[0003] With increasingly stringent requirements, the single-sided bonding and compression resilience of the sealing rings are further enhanced to ensure they do not fall off during handling after assembly. Summary of the Invention

[0004] To address the shortcomings of the existing technology, this invention provides a room-temperature in-situ molded foamed silicone rubber that can form a dense microporous colloid, namely a silicone foam adhesive sealing ring. The specific technical solution is as follows:

[0005] A room-temperature in-situ moldable foamed silicone comprises the following components in parts by weight:

[0006] Component A: 20-50 parts hydroxyl silicone oil, 15-50 parts vinyl silicone oil, 5-20 parts vinyl MQ resin, 20-30 parts aluminum hydroxide, 1-10 parts hydrogen-containing silicone oil, 1-10 parts phenyltris(dimethylsiloxane)silane, 1-10 parts silica, and 0.005-0.1 parts inhibitor.

[0007] Component B: 20-80 parts vinyl silicone oil, 20-30 parts aluminum hydroxide, 1-10 parts modified silicone oil, 1-10 parts silica, 0.05-0.5 parts Pt catalyst, 0.05-0.5 parts Ti catalyst, 0.05-0.1 parts black color paste;

[0008] The structure of the modified silicone oil is shown in formula (Ⅰ):

[0009]

[0010] The foamed silicone of this invention is composed of two components. The modified silicone oil acts as both a coupling agent and a crosslinking agent for the moisture-curing portion. Its reactivity is lower than that of traditional vinyltrimethoxysilane, which can delay the moisture-curing portion of the hydroxyl silicone oil and avoid competition for the foaming portion during the foaming process. After foaming is completed, the hydroxyl groups in the remaining hydroxyl silicone oil can further react with the modified silicone oil at the interface under the action of a titanium catalyst to achieve room temperature adhesion. The addition of phenyltris(dimethylsiloxane)silane in this invention also improves the compression resilience of the formed microporous colloid.

[0011] Furthermore, the preparation equation for the modified silicone oil is as follows:

[0012]

[0013] Furthermore, the method for preparing the modified silicone oil is as follows:

[0014] γ-Methacryloxypropyltrimethoxysilane (KH570) and 1-10 ppm of platinum catalyst were stirred at room temperature for 5-10 min, and then hydrogen-containing silicone oil was slowly added dropwise at room temperature. The molar ratio of hydrogen content of the hydrogen-containing silicone oil to vinyl content of KH570 was (0.9-1.1):1. After the addition was completed, the mixture was stirred at room temperature for 5-6 h to obtain the modified silicone oil.

[0015] Furthermore, in the preparation method of the modified silicone oil, the hydrogen-containing silicone oil has the molecular formula HMe2SiOSiMe2H and a hydrogen content of 14.9 mmol / g; the platinum catalyst is a vinylsiloxane complex of chloroplatinic acid with a platinum content of 2000-6000 ppm.

[0016] Furthermore, the molecular formula of the hydroxyl silicone oil is (HOMe2SiO) 0.5 )2(Me2SiO) m m = 8 to 200, viscosity at 25°C is 50 to 500 mPa·s.

[0017] Furthermore, in component A, the molecular formula of the hydrogen-containing silicone oil is (Me3SiO2). 0.5 )2(Me2SiO) m (HMeSiO) n m = 7–30, n = 24–40, hydrogen content is 0.25–9 mmol / g, and viscosity at 25℃ is 30–75 mPa·S.

[0018] Furthermore, the vinyl MQ resin has a vinyl content of 0.35–0.75 mmol / g and a viscosity of 3000–100000 mPa·S at 25°C.

[0019] Furthermore, the vinyl silicone oil has a vinyl content of 0.025–0.25 mmol / g and a viscosity of 300–9000 mPa·S at 25°C.

[0020] Furthermore, the silica has a specific surface area of ​​120–210 m². 2 / g of hydrophobic silica.

[0021] Furthermore, the aluminum hydroxide has a median particle size D50 of 2-40 μm.

[0022] Furthermore, in component B, the Pt catalyst is a vinylsiloxane complex of chloroplatinic acid, with a platinum content of 3000–6000 ppm.

[0023] Furthermore, the Ti catalyst is one or more of the following: n-butyl titanate, isopropyl titanate, tert-butyl titanate, and ethyl acetoacetate titanium complex.

[0024] Further, the inhibitor is one or more of diethyl fumarate, dibutyl fumarate, 1-ethynyl-1-cyclohexanol, 2-methyl-3-butyn-2-ol, 3-methyl-1-butyn-3-ol, and 3-phenyl-1-butyn-3-ol.

[0025] When using the above-mentioned room temperature in-situ foamed silicone, components A and B are mixed and foamed at a mass ratio of 1:1 to form a dense microporous colloid.

[0026] By adding modified silicone oil, this invention can delay the moisture curing of hydroxyl silicone oil compared to traditional moisture-curing crosslinking agents, and can achieve a certain degree of adhesion at the interface after foaming and being left at room temperature for 3 days.

[0027] The beneficial effects of this invention are as follows:

[0028] The room temperature in-situ foamed silicone provided by this invention is simple to use. The addition of modified silicone oil improves the adhesion between the foamed silicone and the interface; the addition of phenyltris(dimethylsiloxane)silane improves the compression resilience of the formed dense microporous colloid. Detailed Implementation

[0029] The principles and features of the present invention are described below with reference to examples. The examples are only used to explain the present invention and are not intended to limit the scope of the present invention.

[0030] Preparation of modified silicone oil:

[0031] 468.72 g of γ-methacryloxypropyltrimethoxysilane (KH570) and 5 ppm of platinum catalyst were added to a three-necked flask and stirred at room temperature for 10 min. Then, 134 g of hydrogen-containing silicone oil was slowly added dropwise at room temperature. After the addition was complete, the mixture was stirred at room temperature for 5–6 h to obtain the modified silicone oil. The hydrogen-containing silicone oil has the molecular formula HMe2SiOSiMe2H and a hydrogen content of 14.9 mmol / g. The platinum catalyst is a vinylsiloxane complex of chloroplatinic acid with a platinum content of 4000 ppm.

[0032] Example 1:

[0033] A room-temperature in-situ moldable foamed silicone comprises the following components in parts by weight:

[0034] Component A: Hydroxy silicone oil (molecular formula: (HOMe2SiO)) 0.5 )2(Me2SiO) m The following are listed: m=8, viscosity at 25℃ is 450mPa·s); vinyl silicone oil (0.085mmol / g, viscosity at 25℃ is 2000mPa·s); vinyl MQ resin (0.4mmol / g, viscosity at 25℃ is 11000mPa·s); aluminum hydroxide (median particle size D50 is 6um); hydrogen-containing silicone oil (Me3SiO2). 0.5 )2(Me2SiO) m (HMeSiO) n (m=30, n=25, hydrogen content 8.9mmol / g, viscosity at 25℃ 20mPa·s), phenyltris(dimethylsiloxane)silane, silica (specific surface area 140-200m²) 2 The mixture consists of hydrophobic silica (g) and inhibitor (3-methyl-1-butyn-3-ol) in a weight ratio of 30:15:5; 25:3:3:5:0.006.

[0035] Component B: Vinyl silicone oil (0.085 mmol / g, viscosity at 25℃ is 2000 mPa·s), aluminum hydroxide (median particle size D50 is 6 μm), modified silicone oil, and silica (specific surface area is 140–200 m² / g). 2 The mixture consists of hydrophobic silica (4000 ppm platinum), vinyl siloxane complex of chloroplatinic acid (4000 ppm platinum), n-butyl titanate, and black pigment in a weight ratio of 50:25:7.8:3:0.1:0.1:0.06.

[0036] Example 2:

[0037] A room-temperature in-situ moldable foamed silicone comprises the following components in parts by weight:

[0038] Component A: Hydroxy silicone oil (molecular formula: (HOMe2SiO)) 0.5 )2(Me2SiO) m The following are listed: m=8, viscosity at 25℃ is 450mPa·s); vinyl silicone oil (0.085mmol / g, viscosity at 25℃ is 2000mPa·s); vinyl MQ resin (0.4mmol / g, viscosity at 25℃ is 11000mPa·s); aluminum hydroxide (median particle size D50 is 6um); hydrogen-containing silicone oil (Me3SiO2). 0.5 )2(Me2SiO) m (HMeSiO) n(m=30, n=25, hydrogen content 8.9mmol / g, viscosity at 25℃ 20mPa·s), phenyltris(dimethylsiloxane)silane, silica (specific surface area 140-200m²) 2 The composition consists of hydrophobic silica (g) and inhibitor (3-methyl-1-butyn-3-ol) in a weight ratio of 30:15:5; 25:5:1:5:0.006.

[0039] Component B: Vinyl silicone oil (0.085 mmol / g, viscosity at 25℃ is 2000 mPa·s), aluminum hydroxide (median particle size D50 is 6 μm), modified silicone oil, and silica (specific surface area is 140–200 m² / g). 2 The mixture consists of hydrophobic silica (4000 ppm platinum), vinyl siloxane complex of chloroplatinic acid (4000 ppm platinum), n-butyl titanate, and black pigment in a weight ratio of 50:25:7.8:3:0.1:0.1:0.06.

[0040] Comparative Example 1:

[0041] A room-temperature in-situ moldable foamed silicone comprises the following components in parts by weight:

[0042] Component A: Hydroxy silicone oil (molecular formula: (HOMe2SiO)) 0.5 )2(Me2SiO) m The following are listed: m=8, viscosity at 25℃ is 450mPa·s); vinyl silicone oil (0.085mmol / g, viscosity at 25℃ is 2000mPa·s); vinyl MQ resin (0.4mmol / g, viscosity at 25℃ is 11000mPa·s); aluminum hydroxide (median particle size D50 is 6um); hydrogen-containing silicone oil (Me3SiO2). 0.5 )2(Me2SiO) m (HMeSiO) n (m=30, n=25, hydrogen content 8.9mmol / g, viscosity 20mPa·S at 25℃), silica (specific surface area 140~200m²) 2 The composition is based on the following weight ratios: hydrophobic silica (g) and inhibitor (3-methyl-1-butyn-3-ol) 30:15:5; 25:6:5:0.006.

[0043] Component B: Vinyl silicone oil (0.085 mmol / g, viscosity at 25℃ is 2000 mPa·s), aluminum hydroxide (median particle size D50 is 6 μm), modified silicone oil, and silica (specific surface area is 140–200 m² / g). 2The mixture consists of hydrophobic silica (4000 ppm platinum), vinyl siloxane complex of chloroplatinic acid (4000 ppm platinum), n-butyl titanate, and black pigment in a weight ratio of 50:25:7.8:3:0.1:0.1:0.06.

[0044] Comparative Example 2:

[0045] A room-temperature in-situ moldable foamed silicone comprises the following components in parts by weight:

[0046] Component A: Hydroxy silicone oil (molecular formula: (HOMe2SiO)) 0.5 )2(Me2SiO) m The following are listed: m=8, viscosity at 25℃ is 450mPa·s); vinyl silicone oil (0.085mmol / g, viscosity at 25℃ is 2000mPa·s); vinyl MQ resin (0.4mmol / g, viscosity at 25℃ is 11000mPa·s); aluminum hydroxide (median particle size D50 is 6um); hydrogen-containing silicone oil (Me3SiO2). 0.5 )2(Me2SiO) m (HMeSiO) n (m=30, n=25, hydrogen content 8.9mmol / g, viscosity 20mPa·S at 25℃), silica (specific surface area 140~200m²) 2 The composition is based on the following weight ratios: hydrophobic silica (g) and inhibitor (3-methyl-1-butyn-3-ol) 30:15:5; 25:6:5:0.006.

[0047] Component B: Vinyl silicone oil (0.085 mmol / g, viscosity at 25℃ is 2000 mPa·s), aluminum hydroxide (median particle size D50 is 6 μm), vinyltrimethoxysilane, and silica (specific surface area is 140–200 m² / g). 2 The mixture consists of hydrophobic silica (4000 ppm platinum), vinyl siloxane complex of chloroplatinic acid (4000 ppm platinum), n-butyl titanate, and black pigment in a weight ratio of 50:25:7.8:3:0.1:0.1:0.06.

[0048] In the examples and comparative examples, the two components were mixed at a mass ratio of 1:1 and then rapidly foamed to form a dense microporous colloid, which is a sample of a silicone foam adhesive sealing ring.

[0049] The performance of each sample is shown in Table 1, and the test methods are shown in Table 1.

[0050] Table 1 Performance Test Results

[0051]

[0052] Note: The " / " symbol is uneven and cannot be compared in the test.

[0053] The experimental results show that, comparing Examples 1 and 2 with Comparative Example 1, the introduction of phenyltris(dimethylsiloxane)silane improves the compression resilience of the colloid. Comparing Example 1 with Comparative Example 2, the addition of modified silicone oil not only provides excellent adhesion but also balances the speed of the hydroxyl silicone oil during the foaming and curing processes, achieving good adhesion while maintaining the foaming effect.

[0054] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A room temperature in-situ foamed silicone, characterized in that, The components include the following parts by weight: Component A: 20-50 parts hydroxyl silicone oil, 15-50 parts vinyl silicone oil, 5-20 parts vinyl MQ resin, 20-30 parts aluminum hydroxide, 1-10 parts hydrogen-containing silicone oil, 1-10 parts phenyltris(dimethylsiloxane)silane, 1-10 parts silica, 0.005-0.1 parts inhibitor; Component B: 20-80 parts vinyl silicone oil, 20-30 parts aluminum hydroxide, 1-10 parts modified silicone oil, 1-10 parts silica, 0.05-0.5 parts Pt catalyst, 0.05-0.5 parts Ti catalyst, 0.05-0.1 parts black color paste; The structure of the modified silicone oil is shown in formula (Ⅰ): 。 2. The room temperature in-situ foamed silicone according to claim 1, characterized in that, The preparation equation for the modified silicone oil is shown below: 。 3. The room temperature in-situ foamed silicone according to claim 2, characterized in that, The method for preparing the modified silicone oil includes the following steps: γ-methacryloxypropyltrimethoxysilane KH570 and 1-10 ppm of platinum catalyst were stirred at room temperature for 5-10 min, and then hydrogen-containing silicone oil was slowly added dropwise at room temperature. The molar ratio of hydrogen content of the hydrogen-containing silicone oil to vinyl content of KH570 was (0.9-1.1):

1. After the addition was completed, the mixture was stirred at room temperature for 5-6 h to obtain the modified silicone oil. The hydrogen-containing silicone oil has the molecular formula HMe2SiOSiMe2H and a hydrogen content of 14.9 mmol / g; the platinum catalyst is a vinylsiloxane complex of chloroplatinic acid with a platinum content of 2000~6000 ppm.

4. The room temperature in-situ foamed silicone according to claim 1, characterized in that, In component A, the molecular formula of the hydroxyl silicone oil is (HOMe2SiO). 0.5 )2(Me2SiO) m The molecular formula of the hydrogen-containing silicone oil is (Me3SiO2), m=8~200, viscosity at 25℃ is 50~500mPa·s. 0.5 )2(Me2SiO) m (HMeSiO) n The chromium content is 0.25-9 mmol / g, and the viscosity at 25℃ is 30-75 mPa·S.

5. The room temperature in-situ foamed silicone according to claim 1, characterized in that, The vinyl MQ resin has a vinyl content of 0.35~0.75 mmol / g and a viscosity of 3000~100000 mPa·S at 25°C.

6. The room temperature in-situ foamed silicone according to claim 1, characterized in that, The vinyl silicone oil has a vinyl content of 0.025~0.25 mmol / g and a viscosity of 300~9000 mPa·S at 25°C.

7. The room temperature in-situ foamed silicone according to claim 1, characterized in that, The silica has a specific surface area of ​​120~210m². 2 / g of hydrophobic silica; the median particle size D50 of the aluminum hydroxide is 2-40μm.

8. The room temperature in-situ foamed silicone according to claim 1, characterized in that, In component B, the Pt catalyst is a vinylsiloxane complex of chloroplatinic acid with a platinum content of 3000-6000 ppm; the Ti catalyst is at least one of tetrabutyl titanate, isopropyl titanate, tert-butyl titanate, and ethyl acetoacetate titanium.

9. The room temperature in-situ foamed silicone according to claim 1, characterized in that, The inhibitor is one or more of the following: diethyl fumarate, dibutyl fumarate, 1-ethynyl-1-cyclohexanol, 2-methyl-3-butyn-2-ol, 3-methyl-1-butyn-3-ol, and 3-phenyl-1-butyn-3-ol.

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