High-stability silicon adhesive for temperature control equipment and preparation method of high-stability silicon adhesive

Abstract

The invention relates to the technical field of organic silicon bonding adhesives, in particular to a high-stability temperature control equipment silicon bonding adhesive and a preparation method thereof.The silicon bonding adhesive is prepared from, by weight, 10-30 parts of amino silicon oil, 70-90 parts of epoxy resin, 2-8 parts of a coupling agent, 0.1-0.5 part of a catalyst, 5-10 parts of a curing agent, 3-7 parts of a diluent and 2-10 parts of a tackifier. 5-10 parts of a flexibilizer, 1-3 parts of a flame retardant, 2-6 parts of a stabilizer, 5-8 parts of a wetting agent and 1-5 parts of inorganic nanoparticles. The tensile strength and the shear strength of the prepared silicon adhesive are remarkably improved, stable performance is still kept under different environmental conditions, the silicon adhesive has excellent heat resistance, cold resistance, water resistance and adhesive performance, the service life of the silicon adhesive is effectively prolonged, and the high-stability adhesive requirement of the electronic industry can be met.

Description

Technical Field

[0001] The present application belongs to the technical field of organic silicon adhesives, and in particular, relates to a highly stable silicone adhesive for temperature control equipment and a preparation method thereof. Background Art

[0002] Temperature control equipment refers to a series of automatic control components that produce certain special effects and conduction or disconnection actions by physically deforming the switch inside according to the temperature changes in the working environment. It is also called temperature control switch, temperature protector, temperature controller, or simply thermostat. Thermostat adhesive is a bonding material specially used in temperature control equipment. It needs to have characteristics such as high temperature resistance, cold resistance, water resistance, and weather resistance, and be able to maintain stable performance in extreme environments. This glue is usually used to fix and connect various components of the thermostat, such as sensors, circuit boards, and housings. Since the thermostat needs to work under different temperature conditions, the adhesive used must be able to withstand temperature changes without deformation or loss of viscosity.

[0003] With the development of electronic components and electrical technology, the requirements for various performances of adhesive materials used in this field are getting higher and higher. The commonly used adhesives on the market often have low bonding strength and low structural bonding shear force. In addition, traditional adhesives can only play the best bonding role at a specific temperature, and the scope of application is limited. In addition, existing adhesives are easy to lose viscosity in a humid environment, and age and break after long-term use, affecting the bonding effect.

[0004] Organic silicon materials have outstanding high and low temperature resistance (-100~250℃), high elasticity, radiation resistance, weather aging resistance, insulation and hydrophobicity, etc., and are considered to be widely used materials to replace traditional adhesives in the field of electronic appliances. However, domestic organic silicon adhesives are still unreliable and unstable in meeting the mechanical requirements in various environments, which seriously affects the service life of silicone adhesives. As a result, many products in the current electronics industry are still overly dependent on foreign brands of organic silicon adhesives. Users urgently need domestic solutions. Therefore, seeking a highly stable temperature control equipment silicone adhesive to meet the needs of adapting to different environments is a technical problem that technicians in this field need to solve urgently. Summary of the invention

[0005] The present invention provides a highly stable silicone adhesive for temperature control equipment and a preparation method thereof. The silicone adhesive can improve tensile strength, shear strength and bonding performance, is more reliable and stable in meeting mechanical requirements in various environments, has excellent heat resistance, cold resistance, water resistance and weather resistance, effectively prolongs the service life of the silicone adhesive, and has broad market prospects.

[0006] In order to solve the above technical problems, one of the purposes of the present invention is to provide a highly stable silicone adhesive for temperature control equipment, comprising the following components in parts by weight: 10-30 parts of amino silicone oil; Epoxy resin 70-90 parts; 2-8 parts of coupling agent; Catalyst 0.1-0.5 parts; 5-10 parts of curing agent; 3-7 parts of diluent; 2-10 parts of tackifier; 5-10 parts of toughening agent; 1-3 parts of flame retardant; 2-6 parts of stabilizer; Wetting agent 5-8 parts; 1-5 parts of inorganic nanoparticles.

[0007] The amino silicone oil is a silicone softener with a wide range of applications. It has good heat resistance, oxidation resistance, water resistance, weather resistance, compatibility and lubricity, is easy to emulsify, has low surface tension, has good electrical properties, can withstand breakdown voltage and high-voltage arc, has a very small viscosity-temperature coefficient, and has strong compression resistance. The addition of amino silicone oil can effectively enhance the bonding performance of silicone adhesive, improve its flexibility and elasticity, enable it to better adapt to temperature changes and mechanical stress after bonding, and improve the heat resistance, oxidation resistance, water resistance and weather resistance of silicone adhesive, and extend the service life of silicone adhesive. At the same time, it improves its lubricity and smoothness to the substrate, reduces friction during the bonding process, and makes the bonding surface smoother, as well as improves its compatibility and emulsification, and better mixes with other components to form a stable silicone adhesive system, thereby improving the use effect of silicone adhesive.

[0008] The epoxy resin is a high molecular polymer containing multiple polar groups and highly active epoxy groups. It has excellent adhesion, high mechanical properties, good chemical stability, small thermal expansion coefficient, good heat resistance, and is widely used in electronic packaging, adhesives, coatings and other fields. The cured epoxy resin will form a three-dimensional network structure, has good physical and chemical properties, has excellent bonding strength to the surface of metal and non-metallic materials, good dielectric properties, small set shrinkage, good product dimensional stability, high hardness, good flexibility, and is stable to alkali and most solvents. It is widely used as adhesives, anti-corrosion materials, insulating coatings, laminated materials, casting and impregnation materials, molding materials, etc.

[0009] As a preferred embodiment, the coupling agent is coupling agent KH-550.

[0010] As a preferred embodiment, the catalyst is chloroplatinic acid.

[0011] As a preferred embodiment, the curing agent is one or more of polyamide, diethylenetriamine and meta-xylylenediamine.

[0012] As a preferred embodiment, the diluent is dimethyl silicone oil.

[0013] As a preferred embodiment, the tackifier is one or more of aminosilane tackifier, polysiloxane tackifier and n-butyl titanate.

[0014] As a preferred embodiment, the toughening agent is one or more of a rubber CTBN-modified epoxy resin toughening agent, a polyethersulfone toughening agent, and a polyurethane-modified epoxy resin toughening agent.

[0015] As a preferred embodiment, the flame retardant is one or more of aluminum hydroxide, piperazine pyrophosphate and sodium silicate.

[0016] As a preferred embodiment, the stabilizer is glycerol fatty acid ester.

[0017] As a preferred embodiment, the wetting agent is polyoxyethylene ether.

[0018] As a preferred embodiment, the inorganic nanoparticles are nano-SiO2.

[0019] In the silicone adhesive of the present invention, epoxy resin is used as the matrix resin, amino silicone oil is used as the modifier, and under the action of a catalyst, the amino functional group in the amino silicone oil and the epoxy functional group in the epoxy resin can undergo an addition reaction to form compounds such as diamines and hydroxyls, and are connected by silane bonds to form a three-dimensional network structure, effectively improving the performance of the epoxy resin. At the same time, under the action of coupling agent KH-550, inorganic nanoparticles are used to fill, significantly optimize its internal structure, and improve its impact resistance. Then through reasonable compounding of diluents, tackifiers, toughening agents, flame retardants, stabilizers, wetting agents, etc., the bonding performance of the silicone adhesive is effectively enhanced, the hardness, light transmittance, tensile strength, compressive strength and shear strength of the silicone adhesive are improved, the processing properties such as the flowability, operability and curing speed of the silicone adhesive are improved, its heat resistance and aging resistance are significantly improved, and its chemical resistance is improved, while maintaining good flexibility and elasticity, so that the silicone adhesive can still maintain stable performance under outdoor and harsh application conditions. Therefore, the synergistic effect between the components in the silicone adhesive described in the present invention can further improve the stability of the system, obtain excellent bonding ability and mechanical properties, be more reliable and stable in responding to mechanical requirements in various environments, have excellent heat resistance, cold resistance, water resistance and weather resistance, and effectively extend the service life of the silicone adhesive.

[0020] In order to solve the above technical problems, the second object of the present invention is to propose a method for preparing a highly stable temperature control equipment silicone adhesive, comprising the following preparation steps: 1) Prepare raw materials: weigh amino silicone oil, epoxy resin, coupling agent, catalyst, curing agent, diluent, tackifier, toughening agent, flame retardant, stabilizer, wetting agent, and inorganic nanoparticles according to the formula; 2) Preparation of modified epoxy resin: amino silicone oil and epoxy resin are mixed and stirred in a certain proportion, a catalyst is added, and the mixture is reacted at 100° C. for 2.5 hours to obtain modified epoxy resin; 3) After the coupling agent is dissolved in acetone and mixed evenly with a magnetic stirrer, the inorganic nanoparticles are added and treated in an ultrasonic generator for 40-60 minutes to make them evenly dispersed in the solvent; 4) Add the modified epoxy resin to the mixed solution obtained in step 3), stir and mix evenly, heat to about 70°C to remove the acetone solution, and continue to heat to 130°C after 30-50 minutes to strengthen and stabilize the dispersion of the nanoparticles; 5) Add the diluent, tackifier, toughening agent, flame retardant, stabilizer and wetting agent to the mixed solution obtained in step 4) respectively, mix them thoroughly, heat up and vacuum to remove the solvent, add the curing agent to obtain the final silicone adhesive.

[0021] The silicone adhesive of the present invention is based on base resin and amino silicone oil as the main reaction system. Under the action of a catalyst, amino silicone oil can react with epoxy groups and hydroxyl groups in epoxy resin through its active terminal amino groups to generate copolymers, and introduces a stable and flexible Si-O chain in the cured structure, scientifically optimizing the performance of epoxy resin. After being filled with inorganic nanoparticles, the internal structure of the silicone adhesive is effectively optimized, and its impact strength is significantly enhanced. Then, with a tackifier, a toughening agent, a flame retardant, a stabilizer, a wetting agent, and a diluent, the bonding performance and processing performance of the silicone adhesive can be further improved, its mechanical properties can be significantly enhanced, the stability and anti-aging performance of the silicone adhesive can be effectively improved, and the service life of the silicone adhesive can be extended. Finally, a compound curing agent can be used to effectively improve the curing performance of the silicone adhesive, increase the wetting ability of the silicone adhesive, improve its process performance, and make the silicone adhesive more convenient and efficient in practical applications.

[0022] Beneficial effects of the present invention: The present invention uses epoxy resin as the base resin, and uses amino silicone oil for modification under the action of a catalyst to effectively optimize the resin performance, and uses coupling agent KH-550 as a coupling agent, and adds inorganic nanoparticles to effectively fill the internal void structure of the silicone adhesive, significantly enhancing its impact resistance, and forming a silicone adhesive system with excellent adhesion. At the same time, under the coordinated synergistic effect of the tackifier, toughening agent, flame retardant, stabilizer, wetting agent, diluent, and curing agent, on the basis of improving the bonding performance of the silicone adhesive, its tensile strength and shear strength are effectively improved, and it has excellent heat resistance, cold resistance, water resistance, and weather resistance, so that it can still maintain stable performance under different environmental conditions, effectively prolong the service life of the silicone adhesive, and well meet the high stability bonding requirements of the electronics industry. DETAILED DESCRIPTION

[0023] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] Example 1 A highly stable silicone adhesive for temperature control equipment, prepared according to the following weight proportions: 15 parts of amino silicone oil, 85 parts of epoxy resin, 2 parts of coupling agent KH-550, 0.4 parts of chloroplatinic acid, 5 parts of polyamide, 4 parts of dimethyl silicone oil, 10 parts of aminosilane tackifier, 5 parts of rubber CTBN modified epoxy resin toughening agent, 1 part of aluminum hydroxide, 2 parts of glycerol fatty acid ester, 5 parts of polyoxyethylene ether, and 2 parts of nano-SiO2.

[0025] A method for preparing a highly stable temperature control equipment silicone adhesive is as follows: 1) Prepare raw materials: weigh amino silicone oil, epoxy resin, coupling agent KH-550, chloroplatinic acid, polyamide, dimethyl silicone oil, aminosilane tackifier, rubber CTBN modified epoxy resin toughening agent, aluminum hydroxide, glycerol fatty acid ester, polyoxyethylene ether, and nano-SiO2 according to the formula; 2) Preparation of modified epoxy resin: amino silicone oil and epoxy resin are mixed and stirred in a certain proportion, chloroplatinic acid is added, and the mixture is reacted at 100° C. for 2.5 hours to obtain modified epoxy resin; 3) Dissolve the coupling agent KH-550 in acetone and mix it evenly with a magnetic stirrer, then add nano-SiO2 and treat it in an ultrasonic generator for 40-60 minutes to make it evenly dispersed in the solvent; 4) Add the modified epoxy resin to the mixed solution obtained in step 3), stir and mix evenly, heat to about 70°C to remove the acetone solution, and continue to heat to 130°C after 30-50 minutes to strengthen and stabilize the dispersion of the nanoparticles; 5) Dimethyl silicone oil, aminosilane tackifier, rubber CTBN modified epoxy resin toughener, aluminum hydroxide, glycerol fatty acid ester, and polyoxyethylene ether are added to the mixed solution obtained in step 4) respectively, and after being fully mixed, the temperature is increased and vacuumed to remove the solvent, and polyamide is added to obtain the final silicone adhesive.

[0026] Example 2 A highly stable silicone adhesive for temperature control equipment, prepared according to the following weight proportions: 25 parts of amino silicone oil, 75 parts of epoxy resin, 4 parts of coupling agent KH-550, 0.4 parts of chloroplatinic acid, 8 parts of diethylenetriamine, 5 parts of dimethyl silicone oil, 8 parts of polysiloxane tackifier, 6 parts of polyether sulfone toughening agent, 1 part of piperazine pyrophosphate, 4 parts of glycerol fatty acid ester, 6 parts of polyoxyethylene ether, and 4 parts of nano-SiO2.

[0027] A method for preparing a highly stable temperature control equipment silicone adhesive is as follows: 1) Prepare raw materials: weigh amino silicone oil, epoxy resin, coupling agent KH-550, chloroplatinic acid, diethylenetriamine, dimethyl silicone oil, polysiloxane tackifier, polyethersulfone toughening agent, piperazine pyrophosphate, glycerol fatty acid ester, polyoxyethylene ether, and nano-SiO2 according to the formula; 2) Preparation of modified epoxy resin: amino silicone oil and epoxy resin are mixed and stirred in a certain proportion, chloroplatinic acid is added, and the mixture is reacted at 100° C. for 2.5 hours to obtain modified epoxy resin; 3) Dissolve the coupling agent KH-550 in acetone and mix it evenly with a magnetic stirrer, then add nano-SiO2 and treat it in an ultrasonic generator for 40-60 minutes to make it evenly dispersed in the solvent; 4) Add the modified epoxy resin to the mixed solution obtained in step 3), stir and mix evenly, heat to about 70°C to remove the acetone solution, and continue to heat to 130°C after 30-50 minutes to strengthen and stabilize the dispersion of the nanoparticles; 5) Dimethyl silicone oil, polysiloxane tackifier, polyethersulfone toughening agent, piperazine pyrophosphate, glycerol fatty acid ester, and polyoxyethylene ether are added to the mixed solution obtained in step 4) respectively, and after being fully mixed, the temperature is increased and the solvent is removed by vacuuming, and diethylenetriamine is added to obtain the final silicone adhesive.

[0028] Example 3 A highly stable silicone adhesive for temperature control equipment, prepared according to the following weight proportions: 30 parts of amino silicone oil, 70 parts of epoxy resin, 4 parts of coupling agent KH-550, 0.4 parts of chloroplatinic acid, 8 parts of m-phenylenediamine, 5 parts of dimethyl silicone oil, 6 parts of n-butyl titanate, 8 parts of polyurethane modified epoxy resin toughening agent, 2 parts of sodium silicate, 4 parts of glycerol fatty acid ester, 6 parts of polyoxyethylene ether, and 3 parts of nano-SiO2.

[0029] A method for preparing a highly stable temperature control equipment silicone adhesive is as follows: 1) Prepare raw materials: weigh amino silicone oil, epoxy resin, coupling agent KH-550, chloroplatinic acid, m-phenylenediamine, dimethyl silicone oil, n-butyl titanate, polyurethane modified epoxy resin toughening agent, sodium silicate, glycerol fatty acid ester, polyoxyethylene ether, and nano-SiO2 according to the formula; 2) Preparation of modified epoxy resin: amino silicone oil and epoxy resin are mixed and stirred in a certain proportion, chloroplatinic acid is added, and the mixture is reacted at 100° C. for 2.5 hours to obtain modified epoxy resin; 3) Dissolve the coupling agent KH-550 in acetone and mix it evenly with a magnetic stirrer, then add nano-SiO2 and treat it in an ultrasonic generator for 40-60 minutes to make it evenly dispersed in the solvent; 4) Add the modified epoxy resin to the mixed solution obtained in step 3), stir and mix evenly, heat to about 70°C to remove the acetone solution, and continue to heat to 130°C after 30-50 minutes to strengthen and stabilize the dispersion of the nanoparticles; 5) Dimethyl silicone oil, n-butyl titanate, polyurethane modified epoxy resin toughening agent, sodium silicate, glycerol fatty acid ester, and polyoxyethylene ether are added to the mixed solution obtained in step 4) respectively, and after being fully mixed, the temperature is increased and the solvent is removed by vacuuming, and meta-xylylenediamine is added to obtain the final silicone adhesive.

[0030] Example 4 A highly stable silicone adhesive for temperature control equipment, prepared according to the following weight proportions: 20 parts of amino silicone oil, 80 parts of epoxy resin, 6 parts of coupling agent KH-550, 0.4 parts of chloroplatinic acid, 8 parts of polyamide, 6 parts of dimethyl silicone oil, 6 parts of aminosilane tackifier, 8 parts of polyether sulfone toughening agent, 3 parts of sodium silicate, 6 parts of glycerol fatty acid ester, 8 parts of polyoxyethylene ether, and 3 parts of nano-SiO2.

[0031] A method for preparing a highly stable temperature control equipment silicone adhesive is as follows: 1) Prepare raw materials: weigh amino silicone oil, epoxy resin, coupling agent KH-550, chloroplatinic acid, polyamide, dimethyl silicone oil, aminosilane tackifier, polyether sulfone toughening agent, sodium silicate, glycerol fatty acid ester, polyoxyethylene ether, and nano-SiO2 according to the formula; 2) Preparation of modified epoxy resin: amino silicone oil and epoxy resin are mixed and stirred in a certain proportion, chloroplatinic acid is added, and the mixture is reacted at 100° C. for 2.5 hours to obtain modified epoxy resin; 3) Dissolve the coupling agent KH-550 in acetone and mix it evenly with a magnetic stirrer, then add nano-SiO2 and treat it in an ultrasonic generator for 40-60 minutes to make it evenly dispersed in the solvent; 4) Add the modified epoxy resin to the mixed solution obtained in step 3), stir and mix evenly, heat to about 70°C to remove the acetone solution, and continue to heat to 130°C after 30-50 minutes to strengthen and stabilize the dispersion of the nanoparticles; 5) Dimethyl silicone oil, aminosilane tackifier, polyethersulfone toughening agent, sodium silicate, glycerol fatty acid ester, and polyoxyethylene ether are added to the mixed solution obtained in step 4) respectively, and after being fully mixed, the temperature is increased and vacuumed to remove the solvent, and polyamide is added to obtain the final silicone adhesive.

[0032] Example 5 A highly stable silicone adhesive for temperature control equipment, prepared according to the following weight proportions: 30 parts of amino silicone oil, 70 parts of epoxy resin, 8 parts of coupling agent KH-550, 0.4 parts of chloroplatinic acid, 10 parts of meta-phenylenediamine, 6 parts of dimethyl silicone oil, 4 parts of polysiloxane tackifier, 10 parts of polyurethane modified epoxy resin toughening agent, 3 parts of aluminum hydroxide, 6 parts of glycerol fatty acid ester, 8 parts of polyoxyethylene ether, and 3 parts of nano-SiO2.

[0033] A method for preparing a highly stable temperature control equipment silicone adhesive is as follows: 1) Prepare raw materials: weigh amino silicone oil, epoxy resin, coupling agent KH-550, chloroplatinic acid, m-phenylenediamine, dimethyl silicone oil, polysiloxane tackifier, polyurethane modified epoxy resin toughening agent, aluminum hydroxide, glycerol fatty acid ester, polyoxyethylene ether, and nano-SiO2 according to the formula; 2) Preparation of modified epoxy resin: amino silicone oil and epoxy resin are mixed and stirred in a certain proportion, chloroplatinic acid is added, and the mixture is reacted at 100° C. for 2.5 hours to obtain modified epoxy resin; 3) Dissolve the coupling agent KH-550 in acetone and mix it evenly with a magnetic stirrer, then add nano-SiO2 and treat it in an ultrasonic generator for 40-60 minutes to make it evenly dispersed in the solvent; 4) Add the modified epoxy resin to the mixed solution obtained in step 3), stir and mix evenly, heat to about 70°C to remove the acetone solution, and continue to heat to 130°C after 30-50 minutes to strengthen and stabilize the dispersion of the nanoparticles; 5) Add dimethyl silicone oil, polysiloxane tackifier, polyurethane modified epoxy resin toughener, aluminum hydroxide, glycerol fatty acid ester, and polyoxyethylene ether to the mixed solution obtained in step 4), mix thoroughly, heat and vacuum to remove the solvent, add meta-xylylenediamine, and obtain the final silicone adhesive.

[0034] Comparative Example 1 A highly stable silicone adhesive for temperature control equipment, prepared according to the following weight proportions: 20 parts of amino silicone oil, 80 parts of epoxy resin, 0.4 parts of chloroplatinic acid, 8 parts of polyamide, 6 parts of dimethyl silicone oil, 6 parts of aminosilane tackifier, 8 parts of polyether sulfone toughening agent, 3 parts of sodium silicate, 6 parts of glycerol fatty acid ester, 8 parts of polyoxyethylene ether, and 3 parts of nano-SiO2.

[0035] A method for preparing a highly stable temperature control equipment silicone adhesive is as follows: 1) Prepare raw materials: weigh amino silicone oil, epoxy resin, chloroplatinic acid, polyamide, dimethyl silicone oil, aminosilane tackifier, polyether sulfone toughening agent, sodium silicate, glycerol fatty acid ester, polyoxyethylene ether, and nano-SiO2 according to the formula; 2) Preparation of modified epoxy resin: amino silicone oil and epoxy resin are mixed and stirred in a certain proportion, chloroplatinic acid is added, and the mixture is reacted at 100° C. for 2.5 hours to obtain modified epoxy resin; 3) Dissolve the nano-SiO2 in acetone and mix it evenly with a magnetic stirrer, then treat it in an ultrasonic generator for 40-60 minutes to make it evenly dispersed in the solvent; 4) Add the modified epoxy resin to the mixed solution obtained in step 3), stir and mix evenly, heat to about 70°C to remove the acetone solution, and continue to heat to 130°C after 30-50 minutes to strengthen and stabilize the dispersion of the nanoparticles; 5) Dimethyl silicone oil, aminosilane tackifier, polyethersulfone toughening agent, sodium silicate, glycerol fatty acid ester, and polyoxyethylene ether are added to the mixed solution obtained in step 4) respectively, and after being fully mixed, the temperature is increased and vacuumed to remove the solvent, and polyamide is added to obtain the final silicone adhesive.

[0036] Comparative Example 2 A highly stable silicone adhesive for temperature control equipment, prepared according to the following weight proportions: 80 parts of epoxy resin, 6 parts of coupling agent KH-550, 0.4 parts of chloroplatinic acid, 8 parts of polyamide, 6 parts of dimethyl silicone oil, 6 parts of aminosilane tackifier, 8 parts of polyether sulfone toughening agent, 3 parts of sodium silicate, 6 parts of glycerol fatty acid ester, 8 parts of polyoxyethylene ether, and 3 parts of nano-SiO2.

[0037] A method for preparing a highly stable temperature control equipment silicone adhesive is as follows: 1) Prepare raw materials: weigh epoxy resin, coupling agent KH-550, chloroplatinic acid, polyamide, dimethyl silicone oil, aminosilane tackifier, polyethersulfone toughening agent, sodium silicate, glycerol fatty acid ester, polyoxyethylene ether, and nano-SiO2 according to the formula; 2) Add chloroplatinic acid to epoxy resin, mix well, and react at 100°C for 2.5 hours; 3) Dissolve the coupling agent KH-550 in acetone and mix it evenly with a magnetic stirrer, then add nano-SiO2 and treat it in an ultrasonic generator for 40-60 minutes to make it evenly dispersed in the solvent; 4) adding the epoxy resin treated in step 2) to the mixed solution obtained in step 3), stirring and mixing evenly, heating to about 70° C. to remove the acetone solution, and continuing to heat to 130° C. after 30-50 minutes to strengthen and stabilize the dispersion of the nanoparticles; 5) Dimethyl silicone oil, aminosilane tackifier, polyethersulfone toughening agent, sodium silicate, glycerol fatty acid ester, and polyoxyethylene ether are added to the mixed solution obtained in step 4) respectively, and after being fully mixed, the temperature is increased and vacuumed to remove the solvent, and polyamide is added to obtain the final silicone adhesive.

[0038] Comparative Example 3 A highly stable silicone adhesive for temperature control equipment, prepared according to the following weight proportions: 20 parts of amino silicone oil, 80 parts of epoxy resin, 6 parts of coupling agent KH-550, 0.4 parts of chloroplatinic acid, 8 parts of polyamide, 6 parts of dimethyl silicone oil, 6 parts of aminosilane tackifier, 8 parts of nitrile rubber, 3 parts of sodium silicate, 6 parts of glycerol fatty acid ester, 8 parts of polyoxyethylene ether, and 3 parts of nano-SiO2.

[0039] A method for preparing a highly stable temperature control equipment silicone adhesive is as follows: 1) Prepare raw materials: weigh amino silicone oil, epoxy resin, coupling agent KH-550, chloroplatinic acid, polyamide, dimethyl silicone oil, aminosilane tackifier, nitrile rubber, sodium silicate, glycerol fatty acid ester, polyoxyethylene ether, and nano-SiO2 according to the formula; 2) Preparation of modified epoxy resin: amino silicone oil and epoxy resin are mixed and stirred in a certain proportion, chloroplatinic acid is added, and the mixture is reacted at 100° C. for 2.5 hours to obtain modified epoxy resin; 3) Dissolve the coupling agent KH-550 in acetone and mix it evenly with a magnetic stirrer, then add nano-SiO2 and treat it in an ultrasonic generator for 40-60 minutes to make it evenly dispersed in the solvent; 4) Add the modified epoxy resin to the mixed solution obtained in step 3), stir and mix evenly, heat to about 70°C to remove the acetone solution, and continue to heat to 130°C after 30-50 minutes to strengthen and stabilize the dispersion of the nanoparticles; 5) Dimethyl silicone oil, aminosilane tackifier, nitrile rubber, sodium silicate, glycerol fatty acid ester and polyoxyethylene ether are added to the mixed solution obtained in step 4) respectively, and after being fully mixed, the temperature is increased and the solvent is removed by vacuuming, and polyamide is added to obtain the final silicone adhesive.

[0040] The silicone adhesive prepared in Examples 1-5 and Comparative Examples 1-3 was placed in a vacuum drying oven for vacuum degassing for 15 minutes, poured into a mold, heated and cured at 90°C for 1 hour, and then heated and cured at 150°C for 2 hours to prepare samples for the following performance tests.

[0041] Test Example 1 Adhesion Performance Test At room temperature, the ends of a 100 mm × 25 mm × 2 mm aluminum sheet were # Use sandpaper to remove rust and stains to make it smooth and bright. Clean the surface with acetone before use and let it dry. Mix well, pre-bake the silicone adhesive sample, vacuum to remove the solvent, and apply it evenly on the surface of the test piece while it is hot, let it dry for 30-45 minutes, and press to overlap 625mm 2 , put it into the oven and cure it according to the curing conditions.

[0042] Referring to GB 7124-2008 standard, the universal tensile testing machine produced by Gansu Sanshui Instrument Manufacturing Co., Ltd. was used to measure the bonding shear strength of the silicone adhesive to the aluminum sheet, and the bonding performance of the silicone adhesive was evaluated. The results are shown in Table 1.

[0043] Test Example 2 Mechanical Properties Test Referring to GB 1040-79 standard, the XLL-250 tensile testing machine produced by Guangzhou Material Testing Machine Factory was used to measure the tensile strength and elongation at break of the silicone adhesive, and then the mechanical properties of the silicone adhesive were evaluated. The results are shown in Table 1.

[0044] Test Example 3 Hardness Test The hardness of the silicone adhesive was measured according to GB / T 531.1-2008 standard. The results are shown in Table 1.

[0045] Test Example 4 Viscosity Test According to GB / T 2794-1995 standard, the viscosity of the silicone adhesive was measured using a rotational viscometer. The results are shown in Table 1.

[0046] Table 1 It can be seen from the above experimental results and data that the silicone adhesive prepared in Examples 1-5 of the present invention has good shear strength, tensile strength and elongation at break, high hardness and strong viscosity, and its comprehensive performance is significantly better than the silicone adhesive prepared in Comparative Examples 1-3, and meets the high performance requirements of adhesives in the electronics industry.

[0047] Test Example 5 Low Temperature Brittleness Test The low-temperature brittleness of silicone adhesive was measured according to GB / T1682-1994 standard, and the cold resistance of silicone adhesive was evaluated. The results are shown in Table 2.

[0048] Test Example 6 Heat Resistance The silicon bonding silica gel (N2 flow rate of 25 mL / min) was subjected to non-isothermal (temperature range of room temperature to 1000°C) thermal analysis (heating rate of 5°C / min) using a TGA thermal analyzer, and the temperature values ​​at which the mass loss was 10% and 50% were taken respectively. The results are shown in Table 2.

[0049] Test Example 7: Water resistance The aluminum plates were bonded with silicon adhesive and cured, and then placed in a container filled with tap water and soaked for 170 hours. After soaking, they were taken out and observed for debonding. The results are shown in Table 2.

[0050] Table 2 It can be seen from the above experimental results and data that the silicone adhesive prepared in Examples 1-5 of the present invention has weather resistance, heat resistance, cold resistance and water resistance, is more reliable and stable in dealing with different complex environments, has a wider temperature application range, and its stability is significantly better than the silicone adhesive prepared in Comparative Examples 1-3. It can effectively extend the service life of the silicone adhesive and meet the high-stability bonding requirements of the electronics industry.

[0051] Finally, it should be emphasized that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various changes and modifications. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A highly stable silicone adhesive for temperature control equipment, characterized in that: In parts by weight, the silicone adhesive includes the following raw materials: 10-30 parts of amino silicone oil; Epoxy resin 70-90 parts; 2-8 parts of coupling agent; Catalyst 0.1-0.5 parts; 5-10 parts of curing agent; 3-7 parts of diluent; 2-10 parts of tackifier; 5-10 parts of toughening agent; 1-3 parts of flame retardant; 2-6 parts of stabilizer; Wetting agent 5-8 parts; 1-5 parts of inorganic nanoparticles.

2. A highly stable silicone adhesive for temperature control equipment as claimed in claim 1, characterized in that: The coupling agent is coupling agent KH-550.

3. The high-stability silicone adhesive for temperature control equipment according to claim 1, characterized in that: The catalyst is chloroplatinic acid.

4. The high-stability silicone adhesive for temperature control equipment according to claim 1, characterized in that: The curing agent is one or more of polyamide, diethylenetriamine and meta-xylylenediamine.

5. The high-stability silicone adhesive for temperature control equipment according to claim 1, characterized in that: The diluent is dimethyl silicone oil.

6. The high-stability silicone adhesive for temperature control equipment according to claim 1, characterized in that: The tackifier is one or more of an aminosilane tackifier, a polysiloxane tackifier and n-butyl titanate.

7. The high-stability silicone adhesive for temperature control equipment according to claim 1, characterized in that: The toughening agent is one or more of a rubber CTBN-modified epoxy resin toughening agent, a polyethersulfone toughening agent and a polyurethane-modified epoxy resin toughening agent.

8. The high-stability silicone adhesive for temperature control equipment according to claim 1, characterized in that: The flame retardant is one or more of aluminum hydroxide, piperazine pyrophosphate and sodium silicate.

9. The high-stability silicone adhesive for temperature control equipment according to claim 1, characterized in that: The stabilizer is glycerol fatty acid ester; the wetting agent is polyoxyethylene ether.

10. A method for preparing a highly stable temperature control equipment silicone adhesive, characterized in that: The steps include: 1) Prepare raw materials: weigh amino silicone oil, epoxy resin, coupling agent, catalyst, curing agent, diluent, tackifier, toughening agent, flame retardant, stabilizer, wetting agent, and inorganic nanoparticles according to the formula; 2) Preparation of modified epoxy resin: amino silicone oil and epoxy resin are mixed and stirred in a certain proportion, a catalyst is added, and the mixture is reacted at 100° C. for 2.5 hours to obtain modified epoxy resin; 3) After the coupling agent is dissolved in acetone and mixed evenly with a magnetic stirrer, the inorganic nanoparticles are added and treated in an ultrasonic generator for 40-60 minutes to make them evenly dispersed in the solvent; 4) Add the modified epoxy resin to the mixed solution obtained in step 3), stir and mix evenly, heat to about 70°C to remove the acetone solution, and continue to heat to 130°C after 30-50 minutes to strengthen and stabilize the dispersion of the nanoparticles; 5) Add the diluent, tackifier, toughening agent, flame retardant, stabilizer and wetting agent to the mixed solution obtained in step 4) respectively, mix them thoroughly, heat up and vacuum to remove the solvent, add the curing agent to obtain the final silicone adhesive.

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