Dealcoholized silicone sealant and method for preparing the same

Abstract

The application provides a dealcoholized silicone sealant and a preparation method thereof, and belongs to the technical field of sealants, and comprises the following components in parts by weight: alkoxyl-terminated polydimethylsiloxane 100 parts by weight; filler 5-30 parts by weight; crosslinking agent 0.3-15 parts by weight; catalyst 0.05-3 parts by weight; tackifier 0.1-10 parts by weight; by introducing the tackifier with the specific structure in the application, a higher active group component can be provided, so that the dealcoholized silicone sealant provided by the application has excellent bonding performance on various composite substrates such as metals or plastics.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of sealant chemistry, and relates to a dealcoholized silicone sealant and a preparation method thereof. BACKGROUND

[0002] Dealcoholized sealant refers to dealcoholized room temperature vulcanized silicone rubber applied in the field of industrial electronics, which is named because it releases small molecules of methanol or ethanol in the vulcanization process. The glue prepared by taking white carbon black as a reinforcing filler is transparent or translucent, and is mainly applied to the bonding and sealing of electronic appliances, semiconductors and radars.

[0003] The common dealcoholized transparent silicone sealant currently mainly includes two types of dealcoholized type and dealcoholized type. The dealcoholized transparent silicone sealant, commonly known as Nandatransparent glue, is prepared by using Nandatransparent crosslinking agent and silane coupling agent. Due to its poor yellowing resistance, fast surface drying and poor control, the application range is small at present. The dealcoholized transparent silicone sealant includes organotin catalysis and organotitanium catalysis. The organotin catalyzed dealcoholized transparent silicone sealant has poor storage stability, needs to introduce a storage stabilizer with strong odor, and organotin is toxic and not environmentally friendly, which limits the use scene. The organotitanium catalyzed dealcoholized transparent silicone sealant has better environmental protection and storage stability than the organotin catalyzed dealcoholized transparent silicone sealant, and has great application prospect in specific industries, but the organotitanium catalyzed dealcoholized transparent silicone sealant cannot use titanium ester catalysts with color, resulting in poor bonding performance. SUMMARY

[0004] In view of the deficiencies of the prior art, the present application aims to provide a dealcoholized silicone sealant and a preparation method thereof.

[0005] To achieve the purpose of the present application, the following technical solutions are adopted:

[0006] On the one hand, the present application provides a dealcoholized silicone sealant, which comprises the following components by weight:

[0007] 100 parts by weight of alkoxyl-terminated polydimethylsiloxane;

[0008] 5-30 parts by weight of filler;

[0009] 0.3-15 parts by weight of crosslinking agent;

[0010] 0.05-3 parts by weight of catalyst;

[0011] 0.1-10 parts by weight of tackifier.

[0012] The preparation method of the tackifier comprises:

[0013] (1) reacting phenyl glycidyl ether and acrylic compound to obtain a prepolymer;

[0014] (2) reacting the prepolymer, hydrogen-containing polysiloxane and γ-methacryloyloxypropyltrimethoxysilane under the catalysis of platinum gold catalyst to obtain the adhesion promoter.

[0015] The adhesion promoter is prepared by introducing a biphenyl structure compound, wherein the biphenyl structure has strong electronegativity and π electron conjugation effect, and the adhesion promoter can improve the adhesion of active groups to various metal or plastic composite substrates, especially can enhance the adhesion of the sealant in high temperature environment, and has excellent storage stability. That is, by introducing the adhesion promoter into the dealcoholized silicone sealant, excellent adhesion performance can be obtained, and the storage stability is excellent.

[0016] In the present application, the filler 5-30 parts by weight can be 5 parts by weight, 10 parts by weight, 25 parts by weight, 28 parts by weight, 20 parts by weight, 22 parts by weight, 25 parts by weight, 28 parts by weight, 30 parts by weight, etc., the crosslinking agent 0.3-15 parts by weight can be 0.3 parts by weight, 1 parts by weight, 2 parts by weight, 5 parts by weight, 8 parts by weight, 10 parts by weight, 12 parts by weight, 15 parts by weight, etc., the catalyst 0.05-3 parts by weight can be 0.05 parts by weight, 0.1 parts by weight, 0.2 parts by weight, 0.5 parts by weight, 1 parts by weight, 1.5 parts by weight, 2 parts by weight, 2.5 parts by weight, 3 parts by weight, etc., and the adhesion promoter 0.1-10 parts by weight can be 0.1 parts by weight, 1 parts by weight, 2 parts by weight, 3 parts by weight, 5 parts by weight, 6 parts by weight, 8 parts by weight, 10 parts by weight, etc.

[0017] Preferably, the mass ratio of the phenyl glycidyl ether and the acrylic compound is (2-5):1, such as 2:1, 2.5:1, 3:1, 3.5:1, 4:1, 4.5:1, 5:1, etc.

[0018] The phenyl glycidyl ether has the structure shown in formula I:

[0019] ;

[0020] Formula I;

[0021] wherein R 1 is selected from C1-C5 alkylene, such as methylene, ethylene, propylene, etc., preferably methylene and isopropylene.

[0022] Preferably, the phenyl glycidyl ether includes bisphenol F diglycidyl ether and / or bisphenol A diglycidyl ether, having the following structure:

[0023] and / or .

[0024] The source of the phenyl glycidyl ether is not particularly limited in the present application, and any of commercially available products or self-prepared products prepared according to a method known to those skilled in the art can be used.

[0025] The acrylic compound includes any one of acrylic acid, methacrylic acid or 2-ethyl acrylic acid, or a combination of at least two thereof, preferably acrylic acid and / or methacrylic acid. The source of the acrylic compound is not particularly limited in the present application, and any of commercially available products or self-prepared products prepared according to a method known to those skilled in the art can be used.

[0026] The reaction of step (1) is carried out under catalysis of sodium hydroxide.

[0027] The step (1) further includes a retarder, and the retarder is p-hydroxyanisole.

[0028] The reaction of step (1) is carried out at a temperature of 90-110°C, for example 90°C, 95°C, 100°C, 105°C, 110°C, for a time of 4-6 h, for example 4 h, 4.5 h, 5 h, 5.5 h, 6 h, etc.

[0029] Preferably, step (1) is specifically as follows:

[0030] The phenyl glycidyl ether, the acrylic compound, the sodium hydroxide catalyst and the p-hydroxyanisole are mixed, stirred, heated to 90-110°C, and reacted for 4-6 h, and then low-boiling substances are removed by distillation under reduced pressure for 3-4 h, for example 3 h, 3.2 h, 3.5 h, 3.8 h, 4 h, etc., to obtain the prepolymer.

[0031] Preferably, in the step (1), the sodium hydroxide catalyst is added in the form of a sodium hydroxide solution, preferably the concentration of the sodium hydroxide solution is 0.2-0.8%, for example 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, etc., and preferably the amount of the sodium hydroxide solution added is 0.02-0.2% of the total mass of the phenyl glycidyl ether and the acrylic compound, for example 0.02%, 0.05%, 0.08%, 0.1%, 0.12%, 0.15%, 0.18%, 0.2%, etc.

[0032] Preferably, the amount of the p-hydroxyanisole added is 0.1-1% of the total mass of the phenyl glycidyl ether and the acrylic compound, for example 0.1%, 0.2%, 0.4%, 0.5%, 0.6%, 0.8%, 1%, etc.

[0033] Preferably, the hydrogen-containing polysiloxane comprises any one of linear side hydrogen-containing polysiloxane, linear end hydrogen-containing polysiloxane, linear end side hydrogen-containing polysiloxane or 2,4,6,8-tetramethylcyclotetrasiloxane or a combination of at least two of them, preferably linear side hydrogen-containing polysiloxane and / or 2,4,6,8-tetramethylcyclotetrasiloxane.

[0034] The hydrogen-containing polysiloxane has a hydrogen-containing molar amount of 1-25 mmol / g, such as 1 mmol / g, 2 mmol / g, 5 mmol / g, 8 mmol / g, 10 mmol / g, 12 mmol / g, 15 mmol / g, 18 mmol / g, 20 mmol / g, 25 mmol / g, preferably 5-18 mmol / g. The present application does not have special restrictions on the source of the hydrogen-containing polysiloxane, and commercially available products or self-made products prepared according to the preparation method known to those skilled in the art can be used.

[0035] The mass ratio of the prepolymer, hydrogen-containing polysiloxane and γ-methacryloyloxypropyltrimethoxysilane is (30-60):100:(20-40), and the 30-60 can be 30, 35, 40, 45, 50, 55, 60, etc., and the 20-40 can be 20, 22, 25, 28, 30, 32, 35, 38, 40, etc.

[0036] The temperature of the reaction in step (2) is 60-80℃, such as 60℃, 65℃, 70℃, 75℃, 80℃, etc., and the time is 3-4 h, such as 3 h, 3.2 h, 3.5 h, 3.8 h, 4 h, etc.

[0037] Preferably, the platinum content in the platinum catalyst is 1000-5000 ppm, such as 1000 ppm, 2000 ppm, 3000 ppm, 4000 ppm, 5000 ppm, etc., preferably any one of chloroplatinic acid, platinum-vinyl complex, platinum-ethynyl complex or a combination of at least two of them.

[0038] Preferably, step (2) is specifically:

[0039] The temperature is controlled at 60-80℃, and the hydrogen-containing polysiloxane, γ-methacryloyloxypropyltrimethoxysilane and platinum catalyst are added into the prepolymer, and the reaction is continued under nitrogen for 3-4 h to obtain the adhesion promoter.

[0040] In the present application, the content of the adhesion promoter is preferably 0.3-2 parts by weight, such as 0.3 parts by weight, 0.5 parts by weight, 0.8 parts by weight, 1 part by weight, 1.2 parts by weight, 1.5 parts by weight, 1.8 parts by weight, 2 parts by weight, etc.

[0041] Preferably, the alkoxyl-terminated polydimethylsiloxane has the following structure:

[0042]

[0043] wherein m is an integer that makes the viscosity of the polydimethylsiloxane 10-300000 mPa·s at 25℃, such as 10 mPa·s, 100 mPa·s, 1000 mPa·s, 10000 mPa·s, 20000 mPa·s, 50000 mPa·s, 100000 mPa·s, 300000 mPa·s, etc.

[0044] Preferably, the alkoxyl-terminated polydimethylsiloxane has a viscosity of 500-150000 mPa·s at 25℃, such as 500 mPa·s, 1000 mPa·s, 2000 mPa·s, 5000 mPa·s, 8000 mPa·s, 10000 mPa·s, 50000 mPa·s, 80000 mPa·s, 100000 mPa·s, 120000 mPa·s, 150000 mPa·s, etc., further preferably 5000-100000 mPa·s.

[0045] The alkoxyl-terminated polydimethylsiloxane of the present application is not particularly limited in its source, and any commercially available product or self-prepared product prepared according to a method known to those skilled in the art can be used.

[0046] Preferably, the filler is fumed white carbon black with a specific surface area of 100-300 m 2 / g, such as 100 m 2 / g, 120 m 2 / g, 150 m 2 / g, 180 m 2 / g, 200 m 2 / g, 220 m 2 / g, 250 m 2 / g, 280 m 2 / g, 300 m 2 / g, etc.

[0047] Preferably, the fumed white carbon black of the present application is preferably hydrophobically treated, further preferably dimethyldichlorosilane-treated, and has a specific surface area of 150-250 m 2The source of the filler is not particularly limited in the present application, and commercially available products or self-prepared products prepared according to methods known to those skilled in the art can be used. In the present application, the filler is preferably 10-60 parts by weight, for example, 10 parts by weight, 20 parts by weight, 30 parts by weight, 40 parts by weight, 50 parts by weight, 60 parts by weight, etc.

[0048] Preferably, the cross-linking agent is a silane organic compound containing at least three alkoxy active groups, selected from any one or a combination of at least two of methyltrimethoxysilane, methyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, ethyltrimethoxysilane, tetramethoxysilane or tetraethoxysilane, preferably any one or a combination of at least two of methyltrimethoxysilane, vinyltrimethoxysilane or vinyltriethoxysilane. The source of the cross-linking agent is not particularly limited in the present application, and commercially available products or self-prepared products prepared according to methods known to those skilled in the art can be used. In the present application, the cross-linking agent is preferably 0.3-10 parts by weight, for example, 0.3 parts by weight, 1 parts by weight, 2 parts by weight, 3 parts by weight, 4 parts by weight, 5 parts by weight, 6 parts by weight, 7 parts by weight, 8 parts by weight, 9 parts by weight, 10 parts by weight, etc.

[0049] Preferably, the catalyst includes a titanate catalyst and / or an aluminate catalyst.

[0050] Preferably, the catalyst includes any one or a combination of at least two of tetraethyl titanate, isopropyl titanate, tetrabutyl titanate, tetraisobutyl titanate, tetraisooctyl titanate or diisopropyl aluminum acetylacetonate, preferably any one or a combination of at least two of tetraethyl titanate, tetraisobutyl titanate or diisopropyl aluminum acetylacetonate.

[0051] The de-alcoholized silicone sealant provided by the present application has high transparency, excellent adhesion to various substrates at room temperature and high temperature, excellent double 85 resistance, and simple and easy-to-operate preparation method.

[0052] In some embodiments of the present application, the de-alcoholized silicone sealant includes, in parts by weight:

[0053] 100 parts by weight of alkoxy-terminated polydimethylsiloxane;

[0054] 10-30 parts by weight of filler;

[0055] 1-3 parts by weight of cross-linking agent;

[0056] 0.1-1 parts by weight of catalyst;

[0057] 0.3-2 parts by weight of tackifier.

[0058] In a second aspect, the present application provides a preparation method of the dealcoholized silicone sealant as described in the first aspect, the preparation method comprising:

[0059] mixing the components in formula amount to obtain the dealcoholized silicone sealant.

[0060] Preferably, the preparation method comprises:

[0061] S1. mixing the alkoxyl-terminated polydimethylsiloxane and the filler in formula amount to obtain a base;

[0062] S2. mixing the base with the crosslinking agent, the catalyst and the tackifier, and defoaming to obtain the dealcoholized silicone sealant.

[0063] In some embodiments of the present application, the preparation method comprises:

[0064] S1. adding the alkoxyl-terminated polydimethylsiloxane and the filler into a high-speed dispersion planetary mixer, and defoaming and dispersing at 30-90℃, such as 30℃, 40℃, 50℃, 60℃, 70℃, 80℃, 90℃, etc., under a vacuum degree not less than -0.08 MPa (such as -0.08 MPa, -0.09 MPa, etc.) for 1-5 h, such as 1 h, 2 h, 3 h, 4 h, 5 h, etc., to obtain a base;

[0065] S2. mixing the base with the crosslinking agent, the catalyst and the tackifier to stir uniformly at room temperature in a nitrogen atmosphere, and finally defoaming for 10-30 min, such as 10 min, 15 min, 20 min, 25 min, 30 min, etc., under a vacuum degree not less than -0.08 MPa (such as -0.08 MPa, -0.09 MPa, etc.) to obtain the dealcoholized silicone sealant.

[0066] Compared with the prior art, the present application has the following beneficial effects:

[0067] (1) By introducing the tackifier with a specific structure in the present application, a higher active group component can be provided, so that the dealcoholized silicone sealant provided by the present application has excellent bonding performance on various composite substrates of metals or plastics, etc.

[0068] (2) The preparation method provided by the present application is simple and easy to operate, and the conditions are mild, which is suitable for large-scale production and application. DETAILED DESCRIPTION

[0069] The technical solutions of the present application are further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments are only used to help understand the present application and should not be regarded as specific limitations on the present application.

[0070] Unless otherwise specified, the raw materials involved in the following specific embodiments of the present application are all conventional materials in the art and can be purchased through commercially available products. Some raw material information is as follows:

[0071] Alkoxyl-terminated polydimethylsiloxane 1: viscosity 20000 mPa·s, purchased from Jiangsu Keying New Material, J200;

[0072] Alkoxyl-terminated polydimethylsiloxane 2: viscosity 5000 mPa·s, purchased from Orange New Material, O-F5000;

[0073] White carbon black 1: fumed, hydrophobically treated with dimethyldichlorosilane, specific surface area 200 m 2 / g, purchased from Wacker, Germany, HDK H20;

[0074] White carbon black 2: fumed, hydrophobically treated with dimethyldichlorosilane, specific surface area 220 m 2 / g, purchased from Evonik, Aerosil R976 s;

[0075] White carbon black 3: fumed, hydrophobically treated with dimethyldichlorosilane, specific surface area 150 m 2 / g, purchased from Evonik, Aerosil R974;

[0076] White carbon black 4: fumed, specific surface area 100 m 2 / g, purchased from Evonik, Aerosil 90;

[0077] Hydrogen-containing polysiloxane 1: linear side hydrogen-containing polysiloxane, hydrogen-containing molar amount 7 mmol / g, purchased from Andsil, Andsil XL-10;

[0078] Hydrogen-containing polysiloxane 2: linear side hydrogen-containing polysiloxane, hydrogen-containing molar amount 7 mmol / g, purchased from Haido New Material, DTH-075t-50;

[0079] Hydrogen-containing polysiloxane 3: 2,4,6,8-tetramethylcyclotetrasiloxane, purchased from Jiangxi Betley New Material, D4H.

[0080] Preparation Example 1

[0081] The present preparation example provides a preparation method of an adhesion promoter, as follows:

[0082] (1) Bisphenol F diglycidyl ether 30 parts by weight, acrylic acid 10 parts by weight, 0.7% KOH catalyst 0.3 parts by weight and p-hydroxyanisole 0.1 parts by weight were added to a three-necked flask equipped with a stirrer and reflux condenser, and heated while stirring at a stirring speed of 200 r / min, and the temperature was set at 100°C. After stirring for 4 h, low boiling point components were removed under reduced pressure for 3 h to obtain a prepolymer.

[0083] (2) Linear side hydrogen-containing polysiloxane 40 parts by weight having a hydrogen content of 7 mmol / g, γ-methacryloxypropyltrimethoxysilane 5 parts by weight and chloroplatinic acid 0.05 parts by weight having a platinum content of 2000 ppm were added to the prepolymer, and the temperature was set at 80°C and the stirring speed was set at 500 r / min. After stirring for 3 h under nitrogen, an adhesion promoter 1 was obtained.

[0084] Preparation Example 2

[0085] The present preparation example provides a method for preparing an adhesion promoter as follows:

[0086] (1) Bisphenol A diglycidyl ether 40 parts by weight, methacrylic acid 8 parts by weight, 0.5% KOH catalyst 0.6 parts by weight and p-hydroxyanisole 0.3 parts by weight were added to a three-necked flask equipped with a stirrer and reflux condenser, and heated while stirring at a stirring speed of 200 r / min, and the temperature was set at 90°C. After stirring for 6 h, low boiling point components were removed under reduced pressure for 3 h to obtain a prepolymer.

[0087] (2) Linear side hydrogen-containing polysiloxane 30 parts by weight having a hydrogen content of 13 mmol / g, γ-methacryloxypropyltrimethoxysilane 8 parts by weight and platinum-vinyl complex 0.08 parts by weight having a platinum content of 2000 ppm were added to the prepolymer, and the temperature was set at 60°C and the stirring speed was set at 500 r / min. After stirring for 4 h under nitrogen, an adhesion promoter 2 was obtained.

[0088] Preparation Example 3

[0089] The present preparation example provides a method for preparing an adhesion promoter as follows:

[0090] (1) Bisphenol A diglycidyl ether 20 parts by weight, acrylic acid 10 parts by weight, 0.7% KOH catalyst 0.2 parts by weight and p-hydroxyanisole 0.3 parts by weight were added to a three-necked flask equipped with a stirrer and reflux condenser, and heated while stirring at a stirring speed of 200 r / min, and the temperature was set at 110°C. After stirring for 5 h, low boiling point components were removed under reduced pressure for 4 h to obtain a prepolymer.

[0091] (2) In the prepolymer, 2,4,6,8-tetramethylcyclotetrasiloxane 15 parts by weight, γ-methacryloxypropyltrimethoxysilane 2 parts by weight and platinum-vinyl complex with platinum content of 2000 ppm 0.1 parts by weight were added, the temperature was set to 70°C, the stirring speed was 500 r / min, and stirring was carried out under nitrogen protection for 3 h to obtain tackifier 3.

[0092] Comparative Preparation Example 1

[0093] This comparative preparation example provides a preparation method of a tackifier, as follows:

[0094] The difference from Preparation Example 1 is only that in this comparative preparation example 1, no bisphenol F diglycidyl ether is added in step (1), and 40 parts by weight of acrylic acid is directly added, which is denoted as tackifier 4.

[0095] Comparative Preparation Example 2

[0096] This comparative preparation example provides a preparation method of a tackifier, as follows:

[0097] The difference from Preparation Example 1 is only that in this comparative preparation example 1, bisphenol F diglycidyl ether in step (1) is replaced by an equal amount of ethylene glycol diglycidyl ether, which is denoted as tackifier 5.

[0098] Examples 1-7

[0099] This example provides a dealcoholized silicone sealant and a preparation method thereof, wherein the components and their parts by weight are shown in Table 1:

[0100] Table 1

[0101]

[0102] The preparation method is as follows:

[0103] (1) Alkoxyl-terminated polydimethylsiloxane and fumed white carbon black were added to a high-speed dispersion planetary machine for stirring, the temperature was heated to 60°C, and vacuum degassing and dispersion were carried out at-0.08 MPa for 2.5 h to obtain a base material;

[0104] (2) The base material was cooled to below 50°C, the crosslinking agent was added, and stirring was carried out under nitrogen atmosphere for 10 min until uniform mixing; then the catalyst was added, and stirring was continued under nitrogen atmosphere for 10 min until uniform mixing; finally, the tackifier was added, and stirring was carried out under nitrogen atmosphere for 10 min until uniform mixing, and finally, vacuum degassing was carried out at a vacuum degree not less than-0.08 MPa for 20 min to obtain a dealcoholized transparent silicone sealant.

[0105] Comparative Example 1

[0106] The present comparative example provides a dealcoholized silicone sealant and a preparation method thereof.

[0107] The difference from Example 1 is that in the present comparative example, no tackifier is added.

[0108] Comparative Example 2-3

[0109] The present comparative example provides a dealcoholized silicone sealant and a preparation method thereof.

[0110] The difference from Example 1 is that in the present comparative example, the tackifier is replaced with the tackifier provided in Comparative Preparation Example 1-2.

[0111] Performance test

[0112] The sealants provided in the examples and comparative examples are subjected to performance tests, and the method is as follows:

[0113] (1) The shear strength of the sealant to ADC12 aluminum, PC, and PBT+GF30% is determined according to the test method described in GB / T 7124-2008 Adhesives-Determination of tensile shear strength;

[0114] (2) The tensile strength is tested according to the test method described in GB / T 528 Rubber-Determination of tensile strength;

[0115] (3) Aging resistance: after curing for 7 days at 25±2℃ and 50±3℃, high-temperature 125℃ aging and 85℃ / 85%RH aging for 1500 h are respectively carried out, and the shear strength and tensile strength are tested after aging according to the above test standards;

[0116] Among them, curing for 7 days at 25±2℃ and 50±3℃ is recorded as condition T1, high-temperature 125℃ aging for 1500 h is recorded as condition T2, and high-temperature 85℃ / 85%RH aging for 1500 h is recorded as condition T3.

[0117] The test results are shown in Tables 2-3:

[0118] Table 2

[0119]

[0120] Table 3

[0121]

[0122] Note: The unit of shear strength is MPa, CF is cohesive failure, and AF is interfacial failure.

[0123] From the examples and performance tests, it can be known that the adhesion of the sealant to various metal and plastic composite substrates is improved by the pi electron conjugation effect and strong electronegativity of the biphenyl structure in the adhesion promoter.

[0124] (4) High temperature shear: the shear piece made of the sealant is placed in a constant temperature oven at 110±3 DEG C for 2 min, and the shear strength of the sealant to ADC12 aluminum, PC, PBT+GF30% at 110±3 DEG C is measured according to the test method described in GB / T7124-2008 Adhesives - Determination of tensile shear strength.

[0125] The test results are shown in Table 4:

[0126] Table 4

[0127]

[0128] Note: the unit of shear strength is MPa, CF is cohesive failure, and AF is interfacial failure.

[0129] From the examples and performance tests, it can be known that the sealant provided by the application still has excellent bonding performance at high temperature.

[0130] In Tables 2-4:

[0131] From the comparison of examples 1-3 and examples 4-6, it can be known that when the amount of each component of the dealcoholized silicone sealant provided by the application is in the preferred range, the obtained sealant has better effect.

[0132] From the comparison of example 1 and example 7, it can be known that the hydrophobic treated fumed white carbon black is preferably used as the filler in the application.

[0133] From the comparison of example 1 and comparative examples 1-3, it can be known that the introduction of the adhesion promoter with a specific structure in the application can greatly increase the bonding performance and aging resistance of the sealant, especially the bonding performance at high temperature.

[0134] The process method of the application is illustrated by the above examples, but the application is not limited to the above process steps, that is, it does not mean that the application must rely on the above process steps to be implemented. Those skilled in the art should understand that any improvement on the application, equivalent replacement of the materials selected by the application, addition of auxiliary ingredients, selection of specific methods, etc. fall within the protection scope and disclosure scope of the application.

Claims

1. A dealcoholized silicone sealant, characterized by, By weight, comprising the following components: Alkoxyl-terminated polydimethylsiloxane 100 parts by weight; Filler 5-30 parts by weight; Crosslinking agent 0.3-15 parts by weight; Catalyst 0.05-3 parts by weight; Tackifier 0.1-10 parts by weight; The preparation method of the tackifier comprises: (1) phenyl glycidyl ether and acrylic compound are reacted to obtain a prepolymer; (2) the prepolymer, hydrogen-containing polysiloxane and γ-methacryloyloxypropyl trimethoxysilane are reacted under the catalysis of platinum catalyst to obtain the tackifier; The mass ratio of the phenyl glycidyl ether and the acrylic compound is (2-5):1; The phenyl glycidyl ether has the structure shown in formula I: ； Formula I; wherein R 1 is selected from C1-C5 alkylene; The acrylic compound includes any one or a combination of at least two of acrylic acid, methacrylic acid or 2-ethyl acrylic acid.

2. The dealcoholized silicone sealant of claim 1, wherein The reaction of step (1) is carried out under the catalysis of sodium hydroxide; The step (1) further includes a retarder, and the retarder is p-hydroxyanisole; The reaction temperature of step (1) is 90-110℃, and the time is 4-6 h.

3. The dealcoholized silicone sealant of claim 1, wherein The hydrogen-containing polysiloxane includes any one or a combination of at least two of linear side hydrogen-containing polysiloxane, linear end hydrogen-containing polysiloxane, linear end side hydrogen-containing polysiloxane or 2,4,6,8-tetramethylcyclotetrasiloxane; The hydrogen-containing polysiloxane has a hydrogen-containing molar amount of 1-25 mmol / g; The mass ratio of the prepolymer, hydrogen-containing polysiloxane and γ-methacryloyloxypropyl trimethoxysilane is (30-60):100:(20-40); The reaction temperature of step (2) is 60-80℃, and the time is 3-4 h.

4. The dealcoholized silicone sealant according to any one of claims 1-3, wherein, The viscosity of the alkoxyl-terminated polydimethylsiloxane at 25℃ is 500-150000 mPa·s.

5. The dealcoholized silicone sealant according to any one of claims 1-3, wherein The filler is fumed white carbon black having a specific surface area of 100-300 m 2 / g.

6. The dealcoholized silicone sealant of any one of claims 1-3, wherein, The crosslinking agent is a silane organic matter containing at least three alkoxy active groups, and is selected from any one or a combination of at least two of methyl trimethoxysilane, methyl triethoxysilane, vinyl trimethoxysilane, vinyl triethoxysilane, ethyl trimethoxysilane, tetramethoxysilane or tetraethoxysilane.

7. The dealcoholized silicone sealant of any one of claims 1-3, wherein, The catalyst includes a titanate catalyst and / or an aluminate catalyst.

8. A process for preparing the dealcoholized silicone sealant according to any one of claims 1 to 7, characterized by, The preparation method comprises: Mixing the components in the formula amount to obtain the dealcoholized silicone sealant.

9. The production method according to claim 8, characterized by, The preparation method comprises: S1. Mixing the formula amount of alkoxyl-terminated polydimethylsiloxane and filler to obtain a base material; S2. Mixing the base material with the crosslinking agent, catalyst and tackifier, and defoaming to obtain the dealcoholized silicone sealant.

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