Low-temperature curing organic silicon adhesive and preparation method thereof

Abstract

The invention relates to the field of organic adhesives, in particular to a low-temperature curing organic silicon adhesive and a preparation method thereof. The adhesive comprises vinyl silicone oil, hydrogen-containing silicone oil, a filler, a silane coupling agent containing reactive silicon hydrogen, a catalyst and an inhibitor. According to the invention, curing under the low temperature condition of 65-105 DEG C is realized, through the synergistic effect of the components, the technical bottleneck that the traditional organic silicon adhesive can only be cured and bonded at high temperature (generally higher than 120 DEG C) is broken through, and excellent high and low temperature resistance, weather resistance and electrical insulation performance of an organic silicon material are maintained.

Description

Technical Field

[0001] This invention relates to the field of organic adhesives, and more specifically, to a low-temperature curing silicone adhesive and its preparation method. Background Technology

[0002] Due to their unique chemical structure, silicone adhesives exhibit excellent high and low temperature resistance, weather resistance, electrical insulation, chemical stability, and flexibility, and are widely used in bonding, sealing, potting, and coating in high-end fields such as electronics, aerospace, automotive manufacturing, new energy, and LED packaging.

[0003] Traditional silicone adhesives, especially addition-curing systems, while offering the advantage of no byproducts, typically require high temperatures (generally above 120°C) for full curing. This characteristic introduces significant application limitations: First, the high-temperature curing process conflicts with the demands of modern manufacturing. Many heat-sensitive materials, such as engineering plastics (PC, ABS), precision electronic components, and flexible printed circuit boards (FPCBs), cannot withstand prolonged high-temperature environments; otherwise, substrate deformation, yellowing, performance degradation, or even damage can easily occur, severely impacting product yield. Second, high-temperature heating conditions are unsuitable for sealing assembled components, greatly limiting the application of traditional silicone adhesives.

[0004] Currently, the industry typically attempts to lower the curing temperature by adding reaction accelerators or using highly active catalysts. However, these methods often have significant drawbacks: highly active catalysts can severely impair the storage stability and working time of the adhesive, posing a risk of gelation; while many accelerators can introduce problems such as curing inhibition and difficulty in deep curing, and may even negatively impact the transparency, mechanical strength, and long-term durability of the cured adhesive, making it difficult to balance processability and reliability.

[0005] Therefore, developing an organosilicon adhesive that can cure rapidly at lower temperatures (such as below 100°C) while maintaining good storage stability, excellent overall performance, and broad substrate compatibility has become a key issue that urgently needs to be addressed in this technical field. It is of great significance for promoting industrial technological progress and expanding application boundaries. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention provides a low-temperature curing silicone adhesive, comprising: vinyl silicone oil, hydrogen-containing silicone oil, filler, silane coupling agent containing reactive silane, catalyst, and inhibitor.

[0007] This application is the first to replace traditional silane coupling agents with silane molecules containing reactive silane hydrogen. The molecular structure contains both Si-H bonds and functional groups (such as alkoxy and epoxy groups), combining the effects of both coupling agents and crosslinking agents. The Si-H bond at one end of the molecule can undergo a hydrosilylation reaction with the C=C bond of vinyl silicone oil at low temperatures of 50-80℃ under the action of a catalyst, covalently connecting to the organosilicon crosslinking network or forming a crosslinking network, unaffected by the low-temperature hydrolysis rate. The functional groups (such as methoxy and ethoxy groups) at the other end of the molecule combine with the hydroxyl groups (-OH) on the filler surface to form a stable interfacial bond. Choosing this silane coupling agent can enhance the interfacial bonding between the filler and the matrix, while simultaneously solving the problems of poor compatibility, insufficient adhesion, and incomplete curing of conventional silane coupling agents at low temperatures.

[0008] In some embodiments, the silane coupling agent containing reactive silane has the structural formula (R... 1 R 2 SiO) m (HR 1 SiO) n or Where m / n is 1 / 3 - 3 / 1; R 1 It is at least one of -H, -CH3, -CH2CH3, and phenyl; R 2 -SiOR 3 2R 4 -X or -R 4 SiR 3 3, R 3 R is at least one of methoxy, ethoxy, methoxyethoxy, or acetoxy. 4 for or At least one of the following, X is at least one of epoxy, vinyl, or methacryloxy, and p is 1-8. An m / n ratio exceeding the specified range may result in excessively low or high crosslinking density. Too low a ratio will lead to a significant decrease in bond strength, mechanical properties, aging resistance, and other properties. Too high a ratio may lead to runaway reaction, internal bubbles, surface blistering, severely affecting mechanical properties, and making the adhesive brittle.

[0009] The siloxane segments containing active silane in this structure can undergo hydrosilylation with the carbon-carbon double bonds (C=C) on the vinyl silicone oil molecular chain under the action of a catalyst, generating stable Si-C covalent bonds, which can stably crosslink with organosilicon, thus acting as both a coupling agent and a crosslinking agent.

[0010] In some embodiments, the low-temperature curing silicone adhesive, by weight, comprises: 70-100 parts of vinyl silicone oil, 0.5-15 parts of hydrogen-containing silicone oil, 20-30 parts of filler, 0.3-1.6 parts of silane coupling agent containing reactive silane, 0.08-0.1 parts of catalyst, and 0.1-0.2 parts of inhibitor.

[0011] The formulation's component content is carefully controlled to balance the rate, temperature, crosslinking density, and system stability of the hydrosilylation reaction, while also considering the adhesive's mechanical properties, workability, and storage stability. For example, a high proportion of 70-100 parts of vinyl silicone oil ensures the system possesses the core characteristics of silicone materials (high and low temperature resistance, weather resistance, and flexibility). When the content is less than 70 parts, insufficient matrix resin leads to a lack of crosslinking network "skeleton," resulting in low strength, stickiness, and poor resistance to media after curing. A content greater than 100 parts will reduce the proportion of other components, leading to insufficient crosslinking density. The appropriate range of hydrogen-containing silicone oil content allows for sufficient reaction between Si-H and C=C bonds, ensuring adequate crosslinking while avoiding excessive Si-H bond residue that could lead to later hydrolytic aging of the adhesive. When the content of hydrogen-containing silicone oil is less than 0.5 parts, there are insufficient cross-linking sites, and the linear vinyl silicone oil cannot fully form a three-dimensional network structure, resulting in incomplete curing of the adhesive, a sticky surface, and extremely poor mechanical properties. When the content is higher than 15 parts, the excessive Si-H bonds lead to excessively high cross-linking density, increased internal stress in the system, increased brittleness of the cured adhesive, and susceptibility to cracking and debonding. Furthermore, the residual Si-H bonds reduce the stability against damp heat. When the filler content is less than 20 parts, the reinforcing effect is not significant, and the improvement in the mechanical properties of the adhesive is limited. When the content is higher than 30 parts, the viscosity of the system increases sharply, resulting in poor flowability during construction, and the filler is prone to agglomeration, leading to an increase in internal defects in the adhesive and a decrease in weather resistance. If the coupling agent content is less than 0.3 parts, it cannot completely cover the filler surface, resulting in poor filler dispersion, numerous interface defects, and minimal improvement in adhesive bonding strength and water resistance. If the content is higher than 1.6 parts, excessive coupling agent will form a "free layer" at the interface, which will reduce interfacial bonding strength, increase costs, and may easily induce self-crosslinking due to the Si-H bonds of the excessive coupling agent, leading to a decrease in system storage stability. If the catalyst content is less than 0.08 parts, the catalytic activity is insufficient, the curing rate is slow, and it may not even be able to cure completely at low temperatures. If the content is higher than 0.1 parts, the catalytic activity is too strong, the system storage stability decreases sharply, and self-crosslinking (gelling) is likely to occur during storage. Excessive platinum will also increase costs and may cause the adhesive to yellow. If the inhibitor content is less than 0.1 parts, the inhibitory effect is insufficient, the system has a short pot life, and it is easy to gel prematurely during construction. If the content is higher than 0.2 parts, it excessively inhibits the catalyst activity, making it difficult to initiate the curing reaction even with heating, resulting in incomplete curing of the adhesive.

[0012] In some embodiments, the vinyl silicone oil has a vinyl content of 0.2-2 mol%.

[0013] Vinyl content is a core parameter that determines the crosslinking network structure of silicone. The selection of this range is precisely adapted to the requirements of the low-temperature curing system: Lower limit of content (0.2 mol%): ensures basic crosslinking, avoids incomplete curing, and ensures that each vinyl silicone oil molecule chain has at least 1-2 vinyl sites that can undergo addition reactions with the Si-H bonds of hydrogen-containing silicone oil; Upper limit of content (2 mol%): controls the crosslinking density and avoids brittle cracking. Excessive vinyl content (>2 mol%) will lead to overly dense crosslinking points, increased rigidity of the network structure, and a sharp increase in internal stress during low-temperature curing, making the adhesive prone to cracking and debonding.

[0014] In some embodiments, the viscosity of the vinyl silicone oil is 500-100,000 mPa•s.

[0015] If the viscosity is below 500 mPa•s, the molecular weight is too small, the mechanical properties of the cross-linked network after curing are poor, the adhesive is easily swollen by the solvent, and the weather resistance is insufficient; if the viscosity is above 100,000 mPa•s, the viscosity is too high, the fluidity during construction is poor (such as difficult to scrape and clogging of the spray gun), and it is easy to generate bubbles when mixed with other components, which leads to an increase in internal defects of the adhesive.

[0016] In some embodiments, the vinyl silicone oil is at least one of terminal vinyl silicone oil or end-side vinyl silicone oil.

[0017] In some embodiments, the hydrogen-containing silicone oil has the structural formula (R 5 R 6 SiO) n1 (R 5 R 7 SiO) m1 Where 0≤n1 / m1≤8, R 5 and R 6 They are at least one of methyl, ethyl, or phenyl, R 7 It is H, with a hydrogen content of 0.01-1 wt%.

[0018] It should be noted that R 5 and R 6 At least one of methyl, ethyl, or phenyl refers to R 5 It is at least one of methyl, ethyl, or phenyl; R 6 It is also at least one of methyl, ethyl, or phenyl, and R 5 and R 6 They can be the same or different.

[0019] In some embodiments, the viscosity of the hydrogen-containing silicone oil is 2-10,000 mPa•s.

[0020] Below 2 mPa•s, the molecular chains are too short, the Si-H bond content is low, and the crosslinking sites are insufficient, resulting in extremely low strength and stickiness of the cured adhesive. At the same time, low-viscosity hydrogen-containing silicone oils are volatile, generating VOC emissions during construction, and are prone to stratification during storage, reducing the stability of the formulation. Above 10,000 mPa•s, the molecular chains are too long and severely entangled, reducing compatibility with vinyl silicone oils, and easily generating bubbles and agglomeration during mixing. Insufficient exposure of Si-H bonds during the reaction significantly slows down the curing rate at low temperatures, and may even lead to incomplete curing. In addition, excessively high viscosity can cause construction difficulties and limit application scenarios.

[0021] In some embodiments, the viscosity of the hydrogen-containing silicone oil is 2-2,000 mPa•s.

[0022] In some embodiments, the viscosity of the hydrogen-containing silicone oil is 30-500 mPa•s.

[0023] In some embodiments, the hydrogen-containing silicone oil is at least one of end-hydrogen-containing silicone oil or end-side hydrogen-containing silicone oil.

[0024] In some embodiments, the filler is at least one of silica, alumina, and nano-calcium carbonate.

[0025] These fillers are highly compatible with coupling agents containing reactive silane, which can significantly improve the overall performance of adhesives.

[0026] In some embodiments, the silicon dioxide is at least one of gaseous, precipitated, or molten phases.

[0027] In some embodiments, the inhibitor is at least one of alkynyl alcohols, fumaric acid compounds, and maleic acid compounds.

[0028] These inhibitors are well-compatible with the formulation system, have reversible inhibitory effects, and have no side effects.

[0029] In some embodiments, the catalyst is at least one of a silicon-hydrogen reaction catalyst, a platinum-based catalyst, a titanium-based catalyst, a rhodium-based catalyst, or a ruthenium-based catalyst.

[0030] These catalysts are all dedicated catalytic systems for hydrosilylation reactions. They can reduce the activation energy of the addition reaction of C=C bonds and Si-H bonds through coordination catalysis, directly triggering the crosslinking reaction of vinyl silicone oil and hydrogen-containing silicone oil without producing by-products, which meets the curing requirements of silicone adhesives for "low shrinkage and no bubbles".

[0031] In some embodiments, the curing temperature is 65-105°C.

[0032] The silicone adhesive of this application significantly reduces the curing temperature, allowing curing to occur below 105°C. This avoids performance defects caused by high temperatures. Compared to high-temperature curing above 120°C, on the one hand, it reduces the disordered thermal motion of silicone molecular chains, resulting in a more uniform three-dimensional cross-linked network structure after curing. The adhesive's mechanical properties, such as flexibility, tensile strength, and tear strength, are more stable; simultaneously, it prevents yellowing of the adhesive layer and the residue of small-molecule volatiles caused by high temperatures. On the other hand, it reduces curing internal stress and improves bonding reliability. Low-temperature curing significantly reduces the difference in thermal expansion coefficients between the adhesive and the substrate, avoiding stress concentration after high-temperature cooling, thereby reducing the risk of adhesive layer cracking and debonding. It is particularly suitable for bonding and coating heat-sensitive substrates (such as PC, ABS plastics, and flexible circuit boards).

[0033] In some embodiments, the curing temperature may be 65-85°C, 85-95°C, or 95-105°C.

[0034] In some embodiments, the curing time is less than 2 hours.

[0035] In some embodiments, the curing time may be less than 1.5 h, less than 1 h, or less than 30 min.

[0036] In some embodiments, curing is performed at 65-85°C for 2 hours, with the interface failure mode being interface failure; curing is performed at 85-95°C for 2 hours, with the interface failure mode being mixed failure (both cohesive failure and interface failure); and curing is performed at 95-105°C for 2 hours, with the interface failure mode being cohesive failure.

[0037] In some embodiments, the bond strength is greater than 1.5 MPa. The interface failure can occur through at least one of cohesive failure or interfacial failure.

[0038] In some embodiments, the bonding interface is at least one of metal, ceramic, rubber, and plastic.

[0039] The bonding interface refers to the bonding substrate, which can satisfy the bonding between different substrates.

[0040] On the other hand, a method for preparing a low-temperature curing silicone adhesive is also provided, comprising: Step a: Mix vinyl silicone oil, hydrogen-containing silicone oil, silane coupling agent containing reactive silane, and inhibitor to obtain the base adhesive.

[0041] Step b: Add the filler to the base adhesive and mix evenly to obtain a mixed adhesive; Step c: Add the catalyst to the mixture and mix evenly to obtain the low-temperature curing silicone adhesive.

[0042] This method is simple, convenient, and widely applicable.

[0043] The beneficial effects of this patent are as follows: By combining the core technologies of "low-temperature high-efficiency catalytic system" and "special interface enhancement technology", a unique material with the advantages of low-temperature rapid curing, excellent bonding strength and wide substrate adaptability is finally achieved, providing a new material for high-end manufacturing fields such as electronic device packaging, aerospace sensor bonding and medical device assembly in low-temperature processing environments.

[0044] Other features and advantages of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the description, claims, etc. Attached Figure Description

[0045] The accompanying drawings are provided to further understand the technical solutions of the present invention and constitute a part of the specification. They are used together with the embodiments of this application to explain the technical solutions of the present invention and do not constitute a limitation on the technical solutions of the present invention.

[0046] Figure 1 This is a schematic diagram illustrating the interface damage modes that occur at different non-curing temperatures according to the present invention. Detailed Implementation

[0047] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of specific embodiments of the present invention. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the described embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0048] The "range" disclosed in this application is defined by a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, which define the boundaries of the particular range. Ranges defined in this way can include or exclude endpoints and can be arbitrarily combined; that is, any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60 to 120 and 80 to 110 are listed for a specific parameter, it is also expected that ranges of 60 to 110 and 80 to 120 are also included. Furthermore, if minimum range values ​​of 1 and 2 are listed, and if maximum range values ​​of 3, 4, and 5 are listed, then the following ranges are all expected: 1 to 3, 1 to 4, 1 to 5, 2 to 3, 2 to 4, and 2 to 5. In this application, unless otherwise stated, the numerical range "a to b" represents a shortened representation of any combination of real numbers between a and b, where a and b are real numbers. For example, the numerical range "0 to 5" means that all real numbers between "0 and 5" have been listed in this article; "0 to 5" is just a shortened representation of these numerical combinations. In addition, when a parameter is stated as an integer ≥ 2, it is equivalent to disclosing that the parameter is, for example, an integer 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0049] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical solutions. Unless otherwise specified, all technical features and optional technical features of this application can be combined to form new technical solutions.

[0050] Unless otherwise specified, all steps of this application may be performed sequentially or randomly, preferably sequentially. For example, if the method includes steps (a) and (b), it means that the method may include steps (a) and (b) performed sequentially, or it may include steps (b) and (a) performed sequentially. For example, if the method may also include step (c), it means that step (c) may be added to the method in any order. For example, the method may include steps (a), (b), and (c), or it may include steps (a), (c), and (b), or it may include steps (c), (a), and (b), etc.

[0051] In this application, "multiple" means two or more (including two).

[0052] Unless otherwise specified, the terms "comprising" and "including" as used in this application can be open-ended or closed-ended. For example, "comprising" and "including" can mean that other components not listed may also be included, or that only the listed components may be included.

[0053] The overall inventive concept of this application achieves low-temperature, high-efficiency curing through the precise ratio of catalyst and inhibitor, and enhances interfacial adhesion strength by adding a special silane coupling agent. The final result is a low-temperature curing silicone adhesive that combines rapid low-temperature curing, excellent adhesive strength, and broad substrate adaptability.

[0054] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0055] Example 1 Take 72 parts of vinyl silicone oil (62 parts of terminal vinyl silicone oil with a vinyl content of 0.2 mol% and a vinyl content of 1000 mPa*s, 10 parts of terminal vinyl silicone oil with a vinyl content of 0.88 mol%) and 13 parts of hydrogen-containing silicone oil (1 part of terminal hydrogen-containing silicone oil with a hydrogen content of 0.013 wt% and a hydrogen content of 0.8 wt% and a hydrogen-containing silicone oil with a hydrogen content of 0.30 mPa*s). Add 1.3 parts of acetylenecyclohexanol and 0.12 parts of cyclohexanol, mix evenly to obtain a base adhesive; add 20 parts of fumed silica to the base adhesive and continue mixing evenly to obtain a mixed adhesive; add 0.09 parts of platinum-based catalyst to the mixed adhesive and mix evenly to obtain an organosilicon mixture.

[0056] Example 2 Take 75 parts of vinyl silicone oil (70 parts of terminal vinyl silicone oil with a vinyl content of 0.2 mol% at 100,000 mPa*s, 5 parts of terminal vinyl silicone oil with a vinyl content of 0.88 mol% at 1000 mPa*s), and 13 parts of hydrogen-containing silicone oil (1 part of terminal hydrogen-containing silicone oil with a hydrogen content of 0.013 wt% at 500 mPa*s, 1 part of terminal hydrogen-containing silicone oil with a hydrogen content of 0.05 wt% at 70 mPa*s, and 11 parts of terminal hydrogen-containing silicone oil with a hydrogen content of 0.8 wt% at 30 mPa*s). Add 1.4 parts of maleic acid compound and 0.12 parts of maleic acid compound, mix evenly to obtain a base gel; add 20 parts of fumed silica to the base gel, continue mixing evenly to obtain a mixed gel; add 0.08 parts of platinum-based catalyst to the mixed gel, mix evenly to obtain an organosilicon mixture.

[0057] Comparative Example 1 Take 75 parts of vinyl silicone oil (70 parts of terminal vinyl silicone oil with a vinyl content of 0.2 mol% at 100,000 mPa*s, 5 parts of terminal vinyl silicone oil with a vinyl content of 0.88 mol% at 1000 mPa*s), 13 parts of hydrogen-containing silicone oil (1 part of terminal hydrogen-containing silicone oil with a hydrogen content of 0.013 wt% at 500 mPa*s, 1 part of terminal hydrogen-containing silicone oil with a hydrogen content of 0.05 wt% at 70 mPa*s, 11 parts of terminal hydrogen-containing silicone oil with a hydrogen content of 0.8 wt% at 30 mPa*s), 1.4 parts of γ-glycidyl etheroxypropyltrimethoxysilane, and 0.12 parts of maleic acid compound, and mix them evenly to obtain a base gel; add 20 parts of fumed silica to the base gel and continue mixing evenly to obtain a mixed gel; add 0.08 parts of platinum-based catalyst to the mixed gel and mix evenly to obtain an organosilicon mixture.

[0058] Comparative Example 2 Take 72 parts of vinyl silicone oil (62 parts of terminal vinyl silicone oil with a vinyl content of 0.2 mol% at 100,000 mPa*s and 10 parts of terminal vinyl silicone oil with a vinyl content of 0.88 mol% at 1000 mPa*s), 13 parts of hydrogen-containing silicone oil (1 part of terminal hydrogen-containing silicone oil with a hydrogen content of 0.013 wt% at 500 mPa*s and 12 parts of terminal hydrogen-containing silicone oil with a hydrogen content of 0.8 wt% at 30 mPa*s), 1.3 parts of γ-methacryloyloxypropyltrimethoxysilane, and 0.12 parts of acetylenecyclohexanol, and mix them evenly to obtain a base gel; add 20 parts of fumed silica to the base gel and continue mixing evenly to obtain a mixed gel; add 0.09 parts of platinum-based catalyst to the mixed gel and mix evenly to obtain an organosilicon mixture.

[0059] The embodiments and comparative examples were cured, and the tensile strength and other properties after curing were tested. Table 1 shows that the mechanical properties of the products obtained from the embodiments of this application are much higher than those of the comparative examples.

[0060] Table 1 shows the test results of the examples and comparative examples.

[0061] Note 1: Tensile test: 150℃, 2h; Standard sample preparation: Si / Ni sheet bonding, curing at 85℃ for 2 hours; PCT aging conditions: placed in an environment of 121℃ temperature, 100% humidity, and 2 atm pressure for 240 hours; High temperature aging conditions: placed at 150℃ for 1000 hours.

[0062] The products of the examples and comparative examples were cured, and the shear properties after curing are shown in Table 2. At curing temperatures of 65-85℃, the interface failure mode was interfacial failure; at curing temperatures of 85-95℃, the interface failure mode was a mixture of cohesive failure and interfacial failure; above curing temperatures of 95℃, the interface failure mode changed to cohesive failure, and the bond strength was significantly improved. For details on the specific interface failure modes, please refer to... Figure 1 Where A: interface failure; B: mixed failure; C: cohesive failure; S represents Si wafer, N represents Ni wafer, and R represents adhesive.

[0063] As can be seen from the comparison of the embodiments and comparative examples, the embodiments of this application can be cured at 65°C, while the comparative examples do not bond at this temperature.

[0064] Table 2 Shear properties of the examples and comparative examples after curing at different temperatures

[0065] Note 2: The curing time is fixed at 2 hours.

[0066] While the embodiments disclosed in this invention are as described above, the content is merely for the purpose of facilitating understanding of the invention and is not intended to limit the invention. Any person skilled in the art to which this invention pertains may make any modifications and changes to the form and details of the implementation without departing from the spirit and scope disclosed herein; however, the scope of patent protection of this invention shall still be determined by the scope defined in the appended claims.

Claims

1. A low-temperature curing silicone adhesive, characterized in that, include: Vinyl silicone oil, hydrogen-containing silicone oil, fillers, silane coupling agents containing reactive silane, catalysts and inhibitors.

2. The low-temperature curing silicone adhesive according to claim 1, characterized in that, The structural formula of the silane coupling agent containing reactive silane is (R 1 R 2 SiO) m (HR 1 SiO) n or Where m / n is 1 / 3 - 3 / 1; R 1 It is at least one of -H, -CH3, -CH2CH3, and phenyl; R 2 For -OSiR 3 2R 4 -X or -R 4 SiR 3 3, R 3 R is at least one of methoxy, ethoxy, methoxyethoxy, or acetoxy. 4 for or At least one of the following, where X is at least one of epoxy, vinyl, or methacryloxy, and p is 1-8.

3. The low-temperature curing silicone adhesive according to claim 1, characterized in that, By weight, it includes: 70-100 parts of vinyl silicone oil, 0.5-15 parts of hydrogen-containing silicone oil, 20-30 parts of filler, 0.3-1.6 parts of silane coupling agent containing reactive silane, 0.08-0.1 parts of catalyst and 0.1-0.2 parts of inhibitor.

4. The low-temperature curing silicone adhesive according to claim 1, characterized in that, The vinyl silicone oil has a vinyl content of 0.2-2 mol%; And / or the viscosity of the vinyl silicone oil is 500-100,000 mPa•s; And / or the vinyl silicone oil is at least one of terminal vinyl silicone oil or end-side vinyl silicone oil.

5. The low-temperature curing silicone adhesive according to claim 1, characterized in that, The structural formula of the hydrogen-containing silicone oil is (R 5 R 6 SiO)n1(R 5 R 7 SiO)m1, where 0≤n1 / m1≤8, R 5 and R 6 They are at least one of methyl, ethyl, or phenyl, R 7 It is H, with a hydrogen content of 0.01-1 wt%; And / or the viscosity of the hydrogen-containing silicone oil is 2-10,000 mPa•s; Preferably, the viscosity of the hydrogen-containing silicone oil is 2-2,000 mPa•s; More preferably, the viscosity of the hydrogen-containing silicone oil is 30-500 mPa•s; And / or the hydrogen-containing silicone oil is at least one of end-hydrogen-containing silicone oil or end-side hydrogen-containing silicone oil.

6. The low-temperature curing silicone adhesive according to claim 1, characterized in that, The filler is at least one of silica, alumina, and nano-calcium carbonate; Preferably, the silica is at least one of gaseous, precipitated, or molten phases; And / or the inhibitor is at least one of an alkynyl alcohol, a fumaric acid compound, or a maleic acid compound; And / or the catalyst is at least one of a silicon-hydrogen reaction catalyst, a platinum-based catalyst, a titanium-based catalyst, a rhodium-based catalyst, or a ruthenium-based catalyst.

7. The low-temperature curing silicone adhesive according to claim 1, characterized in that, The curing temperature is 65-105℃; And / or the curing time is less than 2 hours.

8. The low-temperature curing silicone adhesive according to claim 1, characterized in that, The bond strength is greater than 1.5 MPa.

9. The low-temperature curing silicone adhesive according to any one of claims 1-8, characterized in that, The bonding interface is at least one of metal, ceramic, rubber, and plastic.

10. A method for preparing the low-temperature curing silicone adhesive according to any one of claims 1-9, characterized in that, include: Step a: Mix vinyl silicone oil, hydrogen-containing silicone oil, silane coupling agent containing reactive silane, and inhibitor to obtain the base adhesive; Step b: Add the filler to the base adhesive and mix evenly to obtain a mixed adhesive; Step c: Add the catalyst to the mixture and mix evenly to obtain the low-temperature curing silicone adhesive.

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