Self-leveling high-bonding-strength electronic adhesive and preparation method thereof

Abstract

The invention mainly relates to the field of sealants, the field of daily chemicals and the field of high polymer chemistry, in particular to a self-leveling high-bonding-strength electronic adhesive and a preparation method thereof, and the self-leveling high-bonding-strength electronic adhesive is prepared from the following raw materials in parts by weight: 100 parts of alkoxy-terminated polydimethylsiloxane; 15-35 parts by weight of dimethyl silicone oil; 10-20 parts by weight of a reinforcing filler; 1-3 parts by weight of polyether modified silicone oil; 5-15 parts by weight of a cross-linking agent; 0.5-2 parts by weight of a tackifier; and 1-6 parts by weight of a catalyst. The self-leveling high-bonding-strength electronic adhesive provided by the invention has excellent rheological properties and relatively high strength and bonding performance, can be coated on the surface of an electronic appliance to form a protective layer, and has good three-proofing effects.

Description

Technical Field

[0001] The present invention mainly relates to the "sealant field", "daily chemical field" and "polymer chemistry field", and specifically relates to a self-leveling high-bonding strength electronic adhesive and a preparation method thereof. Background Art

[0002] Silicone chemistry is the science that studies the properties, structure, synthesis and application of silicone compounds, and is an important part of modern organic chemistry. Silicone compounds are widely used in various fields such as construction, electronics, automobiles, aerospace, etc. due to their unique physical and chemical properties, such as high thermal stability, weather resistance, electrical insulation, low surface tension, etc. Among them, silicone rubber is an important silicone material with excellent heat resistance, cold resistance, weather resistance, electrical insulation, ozone resistance and flame resistance. It is widely used in sealing, shockproof, insulation, waterproof, moisture-proof, mildew-proof, corrosion-resistant, lubrication, medical treatment, food and other fields. Polymer chemistry is the science that studies the properties, structure, synthesis and application of polymer compounds, and is an important part of modern chemistry. Polymer compounds refer to organic compounds with a relative molecular mass of more than 10,000. Their characteristics are different from those of low molecular weight compounds, and they are manifested in polydispersity, flexibility, viscoelasticity, crystallizability and biological activity. Sealant preparation technology is the process of mixing, stirring and reacting a variety of raw materials in a certain proportion and order to finally obtain a sealant with specific properties. The performance of sealants depends on the types and proportions of their raw materials, as well as the process conditions during the preparation process.

[0003] The most widely used cross-linking systems of RTV-1 are the deketoxime cross-linking system, the deacetic acid cross-linking system and the dealcoholization cross-linking system. However, ketoxime sealants are corrosive to copper, and deacetic acid sealants have a strong odor. Acidic gases can also corrode metals, which limits the application of deketoxime sealants and deacidified sealants in the fields of electronics and electrical appliances. Dealcoholized sealants are widely used in bonding and sealing in the fields of electronics and electrical appliances, aerospace, automotive industry, high-end medical equipment, etc., and the most dealcoholized sealant products on the market currently use white carbon black as a reinforcing filler, and white carbon black has excellent thixotropy, which also leads to good thixotropic properties of dealcoholized sealants using white carbon black as a reinforcing filler, thus limiting its application as a three-proof sealant in the field of electronic and electrical coating applications.

[0004] The invention provides a self-leveling high-bonding-strength electronic adhesive and a preparation method thereof. Summary of the invention

[0005] The object of the present invention is to provide a self-leveling high-bonding strength electronic adhesive and a preparation method thereof in view of the deficiencies in the prior art.

[0006] In order to solve the above technical problems, the following technical solutions are adopted:

[0007] A self-leveling high-bonding-strength electronic adhesive, comprising alkoxy-terminated polydimethylsiloxane, dimethyl silicone oil, reinforcing filler, polyether-modified silicone oil, a crosslinking agent, a tackifier and a catalyst;

[0008] The alkoxy-terminated polydimethylsiloxane is 100 parts by weight;

[0009] The dimethyl silicone oil is 15 to 35 parts by weight;

[0010] The reinforcing filler is 10 to 20 parts by weight;

[0011] The polyether modified silicone oil is 1 to 3 parts by weight;

[0012] The cross-linking agent is 5 to 15 parts by weight;

[0013] The tackifier is 0.5 to 2 parts by weight;

[0014] The catalyst is 1 to 6 parts by weight;

[0015] The viscosity enhancer is 3-isocyanate propyl trimethoxy silane, γ-glycidyloxypropyl trimethoxy silane and methyl diethoxy silane, and the mass ratio of the 3-isocyanate propyl trimethoxy silane, γ-glycidyloxypropyl trimethoxy silane and methyl diethoxy silane is 1: (1-3): (1-3).

[0016] A further improvement based on the technical solution is that the alkoxy-terminated polydimethylsiloxane is any one of trimethoxy-terminated and triethoxy-terminated or a combination of both.

[0017] A further improvement based on the technical solution is that the alkoxy-terminated polydimethylsiloxane has a kinematic viscosity of 20,000 to 100,000 mm 2 / s.

[0018] A further improvement based on the technical solution is that the kinematic viscosity of the dimethyl silicone oil is 100-350 mm 2 / s.

[0019] A further improvement based on the technical solution is that the reinforcing filler is hydrophilic fumed silica and hydrophobic fumed silica, and the mass ratio of the two is 1:(3-7).

[0020] A further improvement based on the technical solution is that the cross-linking agent is a compound reagent of methyltrimethoxysilane and vinyltrimethoxysilane, wherein the compound mass ratio of methyltrimethoxysilane to vinyltrimethoxysilane is (2-6):1.

[0021] A further improvement based on the technical solution is that the catalyst is a phthalate chelating agent.

[0022] The present invention proposes another technical solution: a method for preparing a self-leveling high-bonding strength electronic adhesive, comprising the following steps:

[0023] S1. Add dimethyl silicone oil and 3-isocyanate propyltrimethoxysilane into a planetary dispersing machine, stir under vacuum for 5 to 10 minutes, then add a hydrophilic reinforcing filler, stir under vacuum for 10 to 30 minutes to obtain a premix.

[0024] S2. Add alkoxy-terminated polydimethylsiloxane, polyether-modified silicone oil and crosslinking agent into a high-speed planetary dispersing machine, stir under vacuum for 5 to 15 minutes, then add hydrophobic reinforcing filler, and stir under vacuum for 15 to 30 minutes.

[0025] S3. Add the premix obtained in step S1 to the mixture in step S2, stir under vacuum for 5 to 15 minutes, then add γ-glycidyloxypropyltrimethoxysilane, (3-glycidoxypropyl)methyldiethoxysilane and a catalyst, stir under vacuum for 5 to 15 minutes, and mix well to obtain the adhesive.

[0026] A further improvement based on the technical solution is that the preparation method of the polyether-modified silicone oil comprises the following steps: first, adding measured hydrogen-containing silicone oil and allyl polyoxyethylene polyoxypropylene ether into a three-necked flask, wherein the ratio of the amount of silicon-hydrogen bond to the amount of vinyl substance is 1:(1.2-1.6), and then heating to 75-95°C under the protection of an inert gas to react; then slowly adding 10-30 μg / g of chloroplatinic acid, reacting at 75-95°C for 6-9h, and then degassing to obtain the polyether-modified silicone oil.

[0027] A further improvement based on the technical solution is that the mass fraction of active hydrogen in the hydrogen-containing silicone oil is 0.0985%, the viscosity is 30-35 mPa·s, and the molar ratio of ethylene oxide to propylene oxide in the allyl polyoxyethylene polyoxypropylene ether is 1:1.5.

[0028] The above technical solution has the following beneficial effects:

[0029] The present invention performs surface treatment on hydrophilic white carbon black and uses it in combination with self-made polyether modified silicone oil, so that the prepared dealcoholized sealant has excellent rheological properties, and at the same time has good strength and bonding properties, so that it can play a good three-proof effect in the application field of electronic and electrical coating.

[0030] The self-leveling high bonding strength electronic adhesive of the present invention adds the above components and adjusts the content of various components to make them interact with each other, so that the adhesive not only has excellent mechanical strength and bonding performance, but also has the characteristics of self-leveling. Specifically, it has the following effects:

[0031] 1. The sealant preparation technology of the present invention clearly stipulates the selection and proportion of raw materials, as well as the process conditions of the preparation process, so that different manufacturers can obtain sealants with the same performance, thereby improving the consistency and reliability of the products.

[0032] 2. In the sealant preparation technology of the present invention, specific proportions and types of raw materials are used, as well as the process conditions of the preparation process are optimized, so that the prepared sealant has excellent heat resistance, cold resistance, weather resistance, electrical insulation, ozone resistance and flame retardancy, thereby improving the performance and service life of the product.

[0033] 3. In the sealant preparation technology of the present invention, the raw materials used and the process conditions of the preparation process are environmentally friendly, reducing pollution to the environment, meeting the requirements of green chemistry, and improving the environmental performance of the product. In general, the sealant preparation technology of the present invention has higher product performance consistency, better product performance and better environmental performance than the prior art, and has significant advantages. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The present invention will be further described below in conjunction with the accompanying drawings:

[0035] Figure 1 It is a comparison chart of leveling properties between the embodiment of the present invention and the comparative example. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is further described in detail below through the accompanying drawings and embodiments. However, it should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the scope of the present invention. In addition, in the following description, the description of known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present invention.

[0037] A self-leveling high-bonding-strength electronic adhesive, comprising alkoxy-terminated polydimethylsiloxane, dimethyl silicone oil, reinforcing filler, polyether-modified silicone oil, a crosslinking agent, a tackifier and a catalyst;

[0038] The alkoxy-terminated polydimethylsiloxane is 100 parts by weight;

[0039] The dimethyl silicone oil is 15 to 35 parts by weight;

[0040] The reinforcing filler is 10 to 20 parts by weight;

[0041] The polyether modified silicone oil is 1 to 3 parts by weight;

[0042] The cross-linking agent is 5 to 15 parts by weight;

[0043] The tackifier is 0.5 to 2 parts by weight;

[0044] The catalyst is 1 to 6 parts by weight;

[0045] As a further illustration of this embodiment, the adhesive comprises 100 parts by weight of alkoxy-terminated polydimethylsiloxane, wherein the alkoxy-terminated polydimethylsiloxane is any one or a combination of trimethoxy-terminated and triethoxy-terminated. The alkoxy-terminated polydimethylsiloxane has a kinematic viscosity of 20,000 to 100,000 mm 2 / s. The preferred kinematic viscosity is 80000mm 2 / s.

[0046] As a further illustration of this embodiment, the adhesive includes 15 to 35 parts by weight of dimethyl silicone oil, preferably 20 to 25 parts by weight, and the kinematic viscosity of the dimethyl silicone oil is 100 to 350 mm2 / s.

[0047] As a further illustration of this embodiment, the adhesive comprises 10 to 20 parts by weight of reinforcing filler, preferably 12 to 16 parts by weight. The reinforcing filler is hydrophilic fumed silica (FST-150) and hydrophobic fumed silica (HB-139), and the mass ratio of the two is 1: (3 to 7), preferably 1: (4 to 5).

[0048] As a further illustration of this embodiment, the adhesive comprises 5 to 15 parts by weight of a crosslinking agent, preferably 9 to 12 parts by weight. The crosslinking agent is a compound reagent of methyltrimethoxysilane and vinyltrimethoxysilane, wherein the compounding mass ratio of methyltrimethoxysilane to vinyltrimethoxysilane is (2 to 6) : 1, preferably (3 to 4) : 1.

[0049] As a further illustration of this embodiment, the adhesive includes 0.5 to 2 parts by weight of a tackifier, preferably 1 to 1.5 parts by weight. The tackifier is 3-isocyanate propyl trimethoxy silane, γ-glycidyloxypropyl trimethoxy silane and methyl diethoxy silane, and the mass ratio of 3-isocyanate propyl trimethoxy silane, γ-glycidyloxypropyl trimethoxy silane and methyl diethoxy silane is 1: (1 to 3): (1 to 3), preferably 1: 2: 2.

[0050] As a further illustration of this embodiment, the adhesive includes 1 to 6 parts by weight of a catalyst, preferably 2 to 4 parts by weight, and the catalyst is a phthalate chelating agent.

[0051] This embodiment proposes another technical solution: a method for preparing a self-leveling high-bonding strength electronic adhesive, comprising the following steps:

[0052] S1. Add dimethyl silicone oil and 3-isocyanate propyltrimethoxysilane into a planetary dispersing machine, stir under vacuum for 5 to 10 minutes, then add a hydrophilic reinforcing filler, stir under vacuum for 10 to 30 minutes to obtain a premix.

[0053] S2. Add alkoxy-terminated polydimethylsiloxane, polyether-modified silicone oil and crosslinking agent into a high-speed planetary dispersing machine, stir under vacuum for 5 to 15 minutes, then add hydrophobic reinforcing filler, and stir under vacuum for 15 to 30 minutes.

[0054] S3. Add the premix obtained in step S1 to the mixture in step S2, stir under vacuum for 5 to 15 minutes, then add γ-glycidyloxypropyltrimethoxysilane, (3-glycidoxypropyl)methyldiethoxysilane and a catalyst, stir under vacuum for 5 to 15 minutes, and mix well to obtain the adhesive.

[0055] Secondly, 3-isocyanate propyl trimethoxy silane, γ-glycidyloxypropyl trimethoxy silane and (3-glycidoxypropyl) methyl diethoxy silane were selected as tackifiers in a mass ratio of 1:(1-3):(1-3) to improve the adhesive properties of the sealant. In addition, hydrophilic fumed silica and hydrophobic fumed silica were selected as reinforcing fillers in a mass ratio of 1:(4-5) to improve the strength and wear resistance of the sealant.

[0056] In the whole preparation process, the vacuum stirring method is adopted, which can effectively reduce the use of organic solvents, reduce VOC emissions, and reduce environmental pollution. At the same time, the selected raw materials and catalysts are environmentally friendly materials, which further reduces environmental pollution.

[0057] As a further illustration of this embodiment, the preparation method of the polyether-modified silicone oil comprises the following steps: first, adding measured hydrogen-containing silicone oil and allyl polyoxyethylene polyoxypropylene ether into a three-necked flask, wherein the ratio of the amount of silicon-hydrogen bond to the amount of vinyl substance is 1:(1.2-1.6), and then heating to 75-95° C. under the protection of an inert gas for reaction; then slowly adding 10-30 μg / g of chloroplatinic acid, reacting at 75-95° C. for 6-9 hours, and then degassing to obtain the polyether-modified silicone oil.

[0058] Among them, hydrogen-containing silicone oil and allyl polyoxyethylene polyoxypropylene ether are selected as basic raw materials, and the ratio of the amount of silicon-hydrogen bond to the amount of vinyl substance is 1: (1.2-1.6) to ensure the smooth progress of the reaction.

[0059] As a further illustration of this embodiment, the active hydrogen mass fraction of the hydrogen-containing silicone oil is 0.0985%, the viscosity is 30-35 mPa·s, and the molar ratio of ethylene oxide to propylene oxide in the allyl polyoxyethylene polyoxypropylene ether is 1:1.5.

[0060] In order to further understand the present invention, the self-leveling high bonding strength electronic adhesive and the preparation method thereof provided by the present invention are described below in conjunction with embodiments. The protection scope of the present invention is not limited by the following embodiments.

[0061] The sealant of the present invention has excellent heat resistance, cold resistance, weather resistance, electrical insulation, ozone resistance and flame resistance, and can effectively prevent the external environment from corroding the internal structure, thereby improving the service life and stability of the product. At the same time, the sealant preparation technology of the present invention is simple and environmentally friendly, which is conducive to large-scale industrial production and meets the market demand for high-performance, environmentally friendly sealants. Therefore, the present invention has broad market prospects and application potential.

[0062] In order to further understand the present invention, the self-leveling high bonding strength electronic adhesive and the preparation method thereof provided by the present invention are described below in conjunction with embodiments. The protection scope of the present invention is not limited by the following embodiments.

[0063] Example 1

[0064] A) First, add the measured amount of hydrogenated silicone oil and allyl polyoxyethylene polyoxypropylene ether into a three-necked flask, the ratio of the amount of silicon-hydrogen bond to the amount of vinyl substance is 1:1.4, and then heat to 95°C under nitrogen protection, and then slowly add 20μg / g of chloroplatinic acid, react at 55°C for 8h, and then desulfurize to obtain polyether-modified silicone oil.

[0065] B) Dimethyl silicone oil with a kinematic viscosity of 350 mm2 / s and 3-isocyanate propyltrimethoxysilane were added to a high-speed planetary dispersing machine, and the mixture was stirred under vacuum for 10 min. Then, hydrophilic fumed silica was added and the mixture was stirred under vacuum for 20 min to obtain a premix.

[0066] C) Add alkoxy-terminated polydimethylsiloxane with a kinematic viscosity of 80,000 mm2 / s, the polyether-modified silicone oil obtained in A) and a crosslinking agent (the compounding mass ratio of methyltrimethoxysilane to vinyltrimethoxysilane is 3:1) in a high-speed planetary disperser, stir in vacuum for 10 minutes, then add hydrophobic fumed silica, and stir in vacuum for 20 minutes.

[0067] D) Add the premix obtained in B) to the mixture in C), stir under vacuum for 10 min, then add γ-glycidyloxypropyltrimethoxysilane, (3-glycidoxypropyl)methyldiethoxysilane and tert-butyl titanate, stir under vacuum for 10 min, and mix well to obtain the above sealant.

[0068] Among them, hydrophilic fumed silica and hydrophobic fumed silica are used as reinforcing fillers in a mass ratio of 1:5; 3-isocyanatepropyltrimethoxysilane, γ-glycidyloxypropyltrimethoxysilane and (3-glycidoxypropyl)methyldiethoxysilane are used as adhesion promoters in a mass ratio of 1:2:2.

[0069] The specific mass ratio is shown in Table 1. The performance of the obtained self-leveling high bonding strength electronic adhesive was measured and the results are shown in Tables 9 and Figure 1 .

[0070] Table 1: Data table of components and contents of self-leveling high bonding strength electronic adhesive in this embodiment

[0071] Components Dosage / Servings Alkoxy-terminated polydimethylsiloxane 100 Dimethicone 35 Reinforcement filler 15 Polyether modified silicone oil 2 Crosslinking agent 10 Tackifier 1.5 catalyst 2

[0072] Example 2

[0073] A) Add measured hydrogen-containing silicone oil and allyl polyoxyethylene polyoxypropylene ether into a three-necked flask, with the ratio of silicon-hydrogen bond to vinyl substance being 1:1.5. Heat to 80°C under nitrogen protection, then slowly drop 15 μg / g of chloroplatinic acid, react at 85°C for 8 hours, and then degas to obtain polyether-modified silicone oil.

[0074] B) Dimethyl silicone oil with a kinematic viscosity of 350 mm2 / s and 3-isocyanatepropyltrimethoxysilane were added to a high-speed planetary dispersing machine, and the mixture was stirred under vacuum for 8 minutes. Then, hydrophilic fumed silica was added, and the mixture was stirred under vacuum for 15 minutes to obtain a premix.

[0075] C) Add alkoxy-terminated polydimethylsiloxane with a kinematic viscosity of 50,000 mm2 / s, the polyether-modified silicone oil obtained in A) and a crosslinking agent (the compounding mass ratio of methyltrimethoxysilane and vinyltrimethoxysilane is 5:1) in a high-speed planetary disperser, stir in vacuum for 10 minutes, then add hydrophobic fumed silica, and stir in vacuum for 15 minutes.

[0076] D) Add the premix obtained in B) to the mixture in C), stir under vacuum for 10 min, then add γ-glycidyloxypropyltrimethoxysilane, (3-glycidoxypropyl)methyldiethoxysilane and tert-butyl titanate, stir under vacuum for 10 min, and mix well to obtain the above sealant.

[0077] Among them, hydrophilic fumed silica and hydrophobic fumed silica are used as reinforcing fillers in a mass ratio of 1:4; 3-isocyanatepropyltrimethoxysilane, γ-glycidyloxypropyltrimethoxysilane and (3-glycidoxypropyl)methyldiethoxysilane are used as adhesion promoters in a mass ratio of 1:2:3.

[0078] The specific mass ratio is shown in Table 2. The performance of the obtained self-leveling high bonding strength electronic adhesive was measured and the results are shown in Tables 9 and Figure 1 .

[0079] Table 2: Data table of components and contents of self-leveling high bonding strength electronic adhesive in this embodiment

[0080] Components Dosage / Servings Alkoxy-terminated polydimethylsiloxane 100 Dimethicone 30 Reinforcement filler 15 Polyether modified silicone oil 3 Crosslinking agent 10 Tackifier 1.5 catalyst 3

[0081] Example 3

[0082] A) Add measured hydrogen-containing silicone oil and allyl polyoxyethylene polyoxypropylene ether into a three-necked flask, with the ratio of silicon-hydrogen bond to vinyl substance being 1:1.2. Heat to 80°C under nitrogen protection, then slowly drop 10 μg / g of chloroplatinic acid, react at 85°C for 9 hours, and then desorb to obtain polyether-modified silicone oil.

[0083] B) Dimethyl silicone oil with a kinematic viscosity of 150 mm2 / s and 3-isocyanatepropyltrimethoxysilane were added to a high-speed planetary dispersing machine, and the mixture was stirred under vacuum for 5 minutes. Then, hydrophilic fumed silica was added and the mixture was stirred under vacuum for 30 minutes to obtain a premix.

[0084] C) Add alkoxy-terminated polydimethylsiloxane with a kinematic viscosity of 80,000 mm2 / s, the polyether-modified silicone oil obtained in A) and a crosslinking agent (the compounding mass ratio of methyltrimethoxysilane to vinyltrimethoxysilane is 3:1) in a high-speed planetary disperser, stir in vacuum for 12 minutes, then add hydrophobic fumed silica, and stir in vacuum for 18 minutes.

[0085] D) Add the premix obtained in B) to the mixture in C), stir under vacuum for 15 minutes, then add γ-glycidyloxypropyltrimethoxysilane, (3-glycidoxypropyl)methyldiethoxysilane and tert-butyl titanate, stir under vacuum for 12 minutes, and mix well to obtain the above sealant.

[0086] Among them, hydrophilic fumed silica and hydrophobic fumed silica are used as reinforcing fillers in a mass ratio of 1:4; 3-isocyanatepropyltrimethoxysilane, γ-glycidyloxypropyltrimethoxysilane and (3-glycidoxypropyl)methyldiethoxysilane are used as adhesion promoters in a mass ratio of 1:3:2.

[0087] The specific mass ratio is shown in Table 3. The performance of the obtained self-leveling high bonding strength electronic adhesive was measured and the results are shown in Tables 9 and Figure 1 .

[0088] Table 3: Data table of components and contents of self-leveling high bonding strength electronic adhesive in this embodiment

[0089] Components Dosage / Servings Alkoxy-terminated polydimethylsiloxane 100 Dimethicone 20 Reinforcement filler 15 Polyether modified silicone oil 1.5 Crosslinking agent 12 Tackifier 2 catalyst 5

[0090] Example 4

[0091] A) Add measured hydrogen-containing silicone oil and allyl polyoxyethylene polyoxypropylene ether into a three-necked flask, with the ratio of silicon-hydrogen bond to vinyl substance being 1:1.2. Heat to 80°C under nitrogen protection, then slowly drop 20 μg / g of chloroplatinic acid, react at 80°C for 7 hours, and then desorb to obtain polyether-modified silicone oil.

[0092] B) Dimethyl silicone oil with a kinematic viscosity of 100 mm2 / s and 3-isocyanatepropyltrimethoxysilane were added to a high-speed dispersing planetary machine, and the mixture was stirred under vacuum for 10 min. Then, hydrophilic fumed silica was added and the mixture was stirred under vacuum for 15 min to obtain a premix.

[0093] C) Add alkoxy-terminated polydimethylsiloxane with a kinematic viscosity of 80,000 mm2 / s, the polyether-modified silicone oil obtained in A) and a crosslinking agent (the compounding mass ratio of methyltrimethoxysilane to vinyltrimethoxysilane is 4:1) in a high-speed planetary disperser, stir in vacuum for 15 minutes, then add hydrophobic fumed silica, and stir in vacuum for 20 minutes.

[0094] D) Add the premix obtained in B) to the mixture in C), stir under vacuum for 5 minutes, then add γ-glycidyloxypropyltrimethoxysilane, (3-glycidoxypropyl)methyldiethoxysilane and tert-butyl titanate, stir under vacuum for 12 minutes, and mix well to obtain the above sealant.

[0095] Among them, hydrophilic fumed silica and hydrophobic fumed silica are used as reinforcing fillers in a mass ratio of 1:4; 3-isocyanatepropyltrimethoxysilane, γ-glycidyloxypropyltrimethoxysilane and (3-glycidoxypropyl)methyldiethoxysilane are used as adhesion promoters in a mass ratio of 1:3:2.

[0096] The specific mass ratio is shown in Table 4. The performance of the obtained self-leveling high bonding strength electronic adhesive was measured and the results are shown in Tables 9 and Figure 1 .

[0097] Table 4: Data table of component contents of self-leveling high bonding strength electronic adhesive in this embodiment

[0098] Components Dosage / Servings Alkoxy-terminated polydimethylsiloxane 100 Dimethicone 30 Reinforcement filler 20 Polyether modified silicone oil 2 Crosslinking agent 10 Tackifier 1.5 catalyst 4

[0099] Example 5

[0100] A) Add measured hydrogen-containing silicone oil and allyl polyoxyethylene polyoxypropylene ether into a three-necked flask, with the ratio of silicon-hydrogen bond to vinyl substance being 1:1.2. Heat to 75°C under nitrogen protection, then slowly drop 15μg / g of chloroplatinic acid, react at 85°C for 7h, then desorb to obtain polyether-modified silicone oil.

[0101] B) Dimethyl silicone oil with a kinematic viscosity of 350 mm2 / s and 3-isocyanatepropyltrimethoxysilane were added to a high-speed dispersing planetary machine, and the mixture was stirred under vacuum for 10 min. Then, hydrophilic fumed silica was added and the mixture was stirred under vacuum for 15 min to obtain a premix.

[0102] C) Add alkoxy-terminated polydimethylsiloxane with a kinematic viscosity of 50,000 mm2 / s, the polyether-modified silicone oil obtained in A) and a crosslinking agent (the compounding mass ratio of methyltrimethoxysilane to vinyltrimethoxysilane is 3:1) in a high-speed planetary disperser, stir in vacuum for 10 minutes, then add hydrophobic fumed silica, and stir in vacuum for 15 minutes.

[0103] D) Add the premix obtained in B) to the mixture in C), stir under vacuum for 15 minutes, then add γ-glycidyloxypropyltrimethoxysilane, (3-glycidoxypropyl)methyldiethoxysilane and tert-butyl titanate, stir under vacuum for 5 minutes, and mix well to obtain the above sealant.

[0104] Among them, hydrophilic fumed silica and hydrophobic fumed silica are used as reinforcing fillers in a mass ratio of 1:3; 3-isocyanatepropyltrimethoxysilane, γ-glycidyloxypropyltrimethoxysilane and (3-glycidoxypropyl)methyldiethoxysilane are used as adhesion promoters in a mass ratio of 1:1:3.

[0105] The specific mass ratio is shown in Table 5. The performance of the obtained self-leveling high bonding strength electronic adhesive was measured and the results are shown in Tables 9 and Figure 1 .

[0106] Table 5: Data table of component contents of self-leveling high bonding strength electronic adhesive in this embodiment

[0107] Components Dosage / Servings Alkoxy-terminated polydimethylsiloxane 100 Dimethicone 15 Reinforcement filler 20 Polyether modified silicone oil 2 Crosslinking agent 15 Tackifier 2 catalyst 4

[0108] Comparative Example 1

[0109] A) Dimethyl silicone oil with a kinematic viscosity of 350 mm2 / s and 3-isocyanate propyltrimethoxysilane were added to a high-speed dispersing planetary machine, and the mixture was stirred under vacuum for 10 min. Then, hydrophilic fumed silica was added and the mixture was stirred under vacuum for 20 min to obtain a premix.

[0110] B) Add alkoxy-terminated polydimethylsiloxane with a kinematic viscosity of 80,000 mm2 / s, polyether-modified silicone oil (dimethyl silicone oil replacement) and a crosslinking agent (the compounding mass ratio of methyltrimethoxysilane and vinyltrimethoxysilane is 3:1) into a high-speed planetary disperser, stir under vacuum for 10 minutes, then add hydrophobic fumed silica and stir under vacuum for 20 minutes.

[0111] C) adding the premix obtained in A) to the mixture in B), stirring under vacuum for 10 min, then adding γ-glycidyloxypropyltrimethoxysilane, (3-glycidoxypropyl)methyldiethoxysilane and tert-butyl titanate, stirring under vacuum for 10 min, and mixing evenly to obtain the above sealant.

[0112] Among them, hydrophilic fumed silica and hydrophobic fumed silica are used as reinforcing fillers in a mass ratio of 1:5; 3-isocyanatepropyltrimethoxysilane, γ-glycidyloxypropyltrimethoxysilane and (3-glycidoxypropyl)methyldiethoxysilane are used as adhesion promoters in a mass ratio of 1:2:2.

[0113] The specific mass ratio is shown in Table 6. The performance of the obtained self-leveling high bonding strength electronic adhesive was measured and the results are shown in Tables 9 and Figure 1 .

[0114] Table 6 Data table of component contents of self-leveling high bonding strength electronic adhesive in this embodiment

[0115] Components Dosage / Servings Alkoxy-terminated polydimethylsiloxane 100 Dimethicone 35 Reinforcement filler 15 Polyether modified silicone oil (dimethyl silicone oil replacement) 2 Crosslinking agent 10 Tackifier 1.5 catalyst 2

[0116] Comparative Example 2

[0117] A) Add measured hydrogen-containing silicone oil and allyl polyoxyethylene polyoxypropylene ether into a three-necked flask, with the ratio of silicon-hydrogen bond to vinyl substance being 1:1.4. Heat to 95°C under nitrogen protection, then slowly drop 20μg / g of chloroplatinic acid, react at 55°C for 8h, then desorb to obtain polyether-modified silicone oil.

[0118] B) Dimethyl silicone oil with a kinematic viscosity of 350 mm2 / s and 3-isocyanatepropyltrimethoxysilane were added to a high-speed planetary dispersing machine, and the mixture was stirred under vacuum for 10 min. Then, hydrophobic fumed silica was added, and the mixture was stirred under vacuum for 20 min to obtain a premix.

[0119] C) Add alkoxy-terminated polydimethylsiloxane with a kinematic viscosity of 80,000 mm2 / s, the polyether-modified silicone oil obtained in A) and a crosslinking agent (the compounding mass ratio of methyltrimethoxysilane to vinyltrimethoxysilane is 3:1) in a high-speed planetary disperser, stir in vacuum for 10 minutes, then add hydrophobic fumed silica, and stir in vacuum for 20 minutes.

[0120] D) Add the premix obtained in B) to the mixture in C), stir under vacuum for 10 min, then add γ-glycidyloxypropyltrimethoxysilane, (3-glycidoxypropyl)methyldiethoxysilane and tert-butyl titanate, stir under vacuum for 10 min, and mix well to obtain the above sealant.

[0121] Among them, hydrophobic fumed silica is used as reinforcing filler; 3-isocyanatepropyltrimethoxysilane, γ-glycidyloxypropyltrimethoxysilane and (3-glycidoxypropyl)methyldiethoxysilane are used as adhesion promoters, with a mass ratio of 1:2:2.

[0122] The specific mass ratio is shown in Table 7. The performance of the obtained self-leveling high bonding strength electronic adhesive was measured and the results are shown in Tables 9 and Figure 1 .

[0123] Table 7 Data table of component contents of self-leveling high bonding strength electronic adhesive in this embodiment

[0124] Components Dosage / Servings Alkoxy-terminated polydimethylsiloxane 100 Dimethicone 35 Reinforcement filler 15 Polyether modified silicone oil 2 Crosslinking agent 10 Tackifier 1.5 catalyst 2

[0125] Comparative Example 3

[0126] A) Add measured hydrogen-containing silicone oil and allyl polyoxyethylene polyoxypropylene ether into a three-necked flask, with the ratio of silicon-hydrogen bond to vinyl substance being 1:1.4. Heat to 95°C under nitrogen protection, then slowly drop 20μg / g of chloroplatinic acid, react at 55°C for 8h, then desorb to obtain polyether-modified silicone oil.

[0127] B) Dimethyl silicone oil with a kinematic viscosity of 350 mm2 / s and 3-isocyanate propyltrimethoxysilane were added to a high-speed planetary dispersing machine, and the mixture was stirred under vacuum for 10 min. Then, hydrophilic fumed silica was added and the mixture was stirred under vacuum for 20 min to obtain a premix.

[0128] C) Add alkoxy-terminated polydimethylsiloxane with a kinematic viscosity of 80,000 mm2 / s, the polyether-modified silicone oil obtained in A) and a crosslinking agent (the compounding mass ratio of methyltrimethoxysilane to vinyltrimethoxysilane is 3:1) into a high-speed planetary dispersing machine and stir in a vacuum for 10 minutes.

[0129] D) Add the premix obtained in B) to the mixture in C), stir under vacuum for 10 min, then add γ-glycidyloxypropyltrimethoxysilane, (3-glycidoxypropyl)methyldiethoxysilane and tert-butyl titanate, stir under vacuum for 10 min, and mix well to obtain the above sealant.

[0130] Among them, hydrophilic fumed silica is used as reinforcing filler; 3-isocyanatepropyltrimethoxysilane, γ-glycidyloxypropyltrimethoxysilane and (3-glycidoxypropyl)methyldiethoxysilane are used as adhesion promoters, with a mass ratio of 1:2:2.

[0131] The specific mass ratio is shown in Table 8. The performance of the obtained self-leveling high bonding strength electronic adhesive was measured and the results are shown in Tables 9 and Figure 1 .

[0132] Table 8 Data table of components and contents of self-leveling high bonding strength electronic adhesive in this embodiment

[0133] Components Dosage / Servings Alkoxy-terminated polydimethylsiloxane 100 Dimethicone 35 Reinforcement filler 15 Polyether modified silicone oil 2 Crosslinking agent 10 Tackifier 1.5 catalyst 2

[0134] Table 9 Performance data of implementation cases

[0135]

[0136] The above are only specific embodiments of the present invention, but the technical features of the present invention are not limited thereto. Any simple changes, equivalent replacements or modifications made based on the present invention to solve basically the same technical problems and achieve basically the same technical effects are all included in the protection scope of the present invention.

Claims

1. A self-leveling high bonding strength electronic adhesive, characterized in that: It includes alkoxy-terminated polydimethylsiloxane, dimethyl silicone oil, reinforcing filler, polyether-modified silicone oil, crosslinking agent, tackifier and catalyst; The alkoxy-terminated polydimethylsiloxane is 100 parts by weight; The dimethyl silicone oil is 15 to 35 parts by weight; The reinforcing filler is 10 to 20 parts by weight; The polyether modified silicone oil is 1 to 3 parts by weight; The cross-linking agent is 5 to 15 parts by weight; The tackifier is 0.5 to 2 parts by weight; The catalyst is 1 to 6 parts by weight; The viscosity enhancer is 3-isocyanate propyl trimethoxy silane, γ-glycidyloxypropyl trimethoxy silane and methyl diethoxy silane, and the mass ratio of the 3-isocyanate propyl trimethoxy silane, γ-glycidyloxypropyl trimethoxy silane and methyl diethoxy silane is 1: (1-3): (1-3).

2. A self-leveling high bonding strength electronic adhesive according to claim 1, characterized in that: The alkoxy-terminated polydimethylsiloxane is any one of trimethoxy-terminated and triethoxy-terminated or a combination of both.

3. The self-leveling high bonding strength electronic adhesive according to claim 1, characterized in that: The alkoxy-terminated polydimethylsiloxane has a kinematic viscosity of 20,000 to 100,000 mm 2 / s.

4. The self-leveling high bonding strength electronic adhesive according to claim 1, characterized in that: The kinematic viscosity of the dimethyl silicone oil is 100 to 350 mm 2 / s.

5. The self-leveling high bonding strength electronic adhesive according to claim 1, characterized in that: The reinforcing filler is hydrophilic fumed silica and hydrophobic fumed silica, and the mass ratio of the two is 1: (3-7).

6. The self-leveling high bonding strength electronic adhesive according to claim 1, characterized in that: The crosslinking agent is a compound reagent of methyltrimethoxysilane and vinyltrimethoxysilane, wherein the compounding mass ratio of methyltrimethoxysilane to vinyltrimethoxysilane is (2-6):

1.

7. The self-leveling high bonding strength electronic adhesive according to claim 1, characterized in that: The catalyst is a phthalate chelating agent.

8. A method for preparing a self-leveling high bonding strength electronic adhesive as claimed in any one of claims 1 to 7, characterized in that The following steps are involved: S1. Add dimethyl silicone oil and 3-isocyanate propyl trimethoxy silane to a planetary dispersing machine, stir under vacuum for 5 to 10 minutes, then add a hydrophilic reinforcing filler, stir under vacuum for 10 to 30 minutes to obtain a premix; S2. Add alkoxy-terminated polydimethylsiloxane, polyether-modified silicone oil and crosslinking agent in a high-speed planetary dispersing machine, stir under vacuum for 5 to 15 minutes, then add hydrophobic reinforcing filler, and stir under vacuum for 15 to 30 minutes; S3. Add the premix obtained in step S1 to the mixture in step S2, stir under vacuum for 5 to 15 minutes, then add γ-glycidyloxypropyltrimethoxysilane, (3-glycidoxypropyl)methyldiethoxysilane and a catalyst, stir under vacuum for 5 to 15 minutes, and mix well to obtain the adhesive.

9. The method for preparing a self-leveling high bonding strength electronic adhesive according to claim 8, characterized in that: The preparation method of the polyether-modified silicone oil comprises the following steps: First, add measured hydrogen-containing silicone oil and allyl polyoxyethylene polyoxypropylene ether into a three-necked flask, wherein the ratio of the amount of silicon-hydrogen bond to the amount of vinyl substance is 1: (1.2-1.6), and then heat to 75-95°C under the protection of inert gas for reaction; then slowly add 10-30 μg / g of chloroplatinic acid, react at 75-95°C for 6-9h, and then degas to obtain polyether-modified silicone oil.

10. The method for preparing a self-leveling high bonding strength electronic adhesive according to claim 9, characterized in that: The hydrogen-containing silicone oil has an active hydrogen mass fraction of 0.0985% and a viscosity of 30-35 mPa•s. The molar ratio of ethylene oxide to propylene oxide in the allyl polyoxyethylene polyoxypropylene ether is 1:1.5.

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