IPN multi-element heat-conducting structural adhesive resistant to high and low temperature damp heat and preparation method thereof

Abstract

The invention discloses an IPN multi-element heat-conducting structural adhesive resistant to high and low temperature damp heat and a preparation method thereof, and belongs to the field of IPN multi-element structural adhesives. The structural adhesive is prepared by matching a component A and a component B according to a volume ratio of 0.9: 1.1-1, the component A is prepared from the following raw materials in parts by weight: 10 to 20 parts of silane modified polyether resin A, 10 to 20 parts of silane modified polyether resin B, 2 to 5 parts of amino-containing silane coupling agent, 0.1 to 0.5 part of catalyst, 1 to 2 parts of epoxy curing agent A, 0.5 to 1 part of self-made epoxy curing agent B, 0.1 to 1 part of catalyst, 1 to 3 parts of first aid, 0.01 to 0.03 part of color paste and 50 to 70 parts of first heat-conducting filler; the component B is prepared from the following raw materials: 10 to 20 parts of epoxy resin A, 5 to 10 parts of self-made epoxy resin B, 5 to 10 parts of reactive diluent, 50 to 70 parts of second heat-conducting filler, 0.1 to 1 part of second aid, 0.01 to 0.03 part of color paste and 1 to 1.5 parts of water. The adhesive is environment-friendly in component, has excellent heat-conducting property and excellent operation performance, is smooth in construction, and can be used for firmly bonding a base material.

Description

Technical Field

[0001] The invention relates to the technical field of IPN multi-component structural adhesive preparation, and in particular to an IPN multi-component thermally conductive structural adhesive resistant to high and low temperatures and humidity and a preparation method thereof. Background Art

[0002] With the rapid development of the new energy vehicle industry, electric vehicles have become an important direction of automobile development. As the "heart" of electric vehicles, the stability and reliability of the performance of power battery packs are directly related to the driving status of the car.

[0003] The shortcomings of pure mechanical assembly solutions are increasing, and they cannot meet the ever-increasing safety requirements of power batteries. Adhesive assembly or cooperative assembly makes up for the shortcomings of mechanical assembly. The types of adhesives used in power battery assembly include structural adhesives, thermal conductive adhesives, solder joint protection adhesives, sealants, etc.

[0004] In the power battery pack, the main battery cells will generate a certain amount of heat during the charging and discharging process of chemical reactions. If the heat is not dissipated in time, the temperature inside the battery cell will continue to rise. When it exceeds a certain temperature, the diaphragm inside the battery cell will fail, causing a short circuit, thereby causing thermal runaway of the battery cell and other phenomena. The current battery packs of new energy electric vehicles are designed with a heat dissipation system. Whether it is an air-cooled or water-cooled system, thermal conductive glue can be used between the battery cell and the cooling system to help better conduct heat between the battery and the cooling system.

[0005] At present, the polyurethane thermal conductive structural adhesive for power batteries has obvious deficiencies in comprehensive performance, and it still faces certain challenges in practical applications. As a structural adhesive, it requires good bonding stability and weather resistance, but polyurethane has poor temperature resistance due to its own defects, especially at higher temperatures, the bonding strength decays greatly; on the other hand, it is difficult to take into account both strength and toughness. The use of IPN system thermal conductive structural adhesive can effectively solve the above problems. The epoxy system is matched with the silicone system. The epoxy system has high strength and excellent high temperature resistance, and the silicone system has high toughness and excellent low temperature resistance. The combination of the two can take into account both strength and toughness, but the proportion of the two is crucial to the performance. The wrong proportion or type selection will greatly affect the comprehensive performance. In high temperature and high humidity environments, most adhesives will face serious debonding. At the same time, as a thermal conductive adhesive, in order to ensure excellent thermal conductivity, its large amount of thermal conductive filler filling will affect its viscosity and increase the difficulty of glue construction. Therefore, how to ensure thermal conductivity and good viscosity and thixotropic properties is also very tricky.

[0006] In summary, how to develop a thermally conductive structural adhesive that has good thermal conductivity, construction operability, mechanical properties, weather resistance, and resistance to high and low temperature, wet and heat aging is a technical problem that needs to be urgently solved in this field.

[0007] In view of this, the present invention is proposed. Summary of the invention

[0008] The purpose of the present invention is to provide an IPN multi-element thermal conductive structural adhesive resistant to high and low temperature and humidity and a preparation method thereof, which has environmentally friendly ingredients, excellent thermal conductivity, good viscosity and thixotropic properties, excellent operating effects and process adaptability; it can achieve firm bonding to the substrate, has good mechanical properties, high strength and high toughness, and more importantly, has excellent weather resistance and high and low temperature and humidity aging resistance, thereby solving the above-mentioned technical problems existing in the prior art.

[0009] The objective of the present invention is achieved through the following technical solutions:

[0010] A high-low temperature and humidity-resistant IPN multi-component thermal conductive structural adhesive, the IPN multi-component thermal conductive structural adhesive is composed of component A and component B in a volume ratio of 0.9:1.1-1; wherein,

[0011] Component A includes the following raw materials in parts by weight:

[0012] 10-20 parts of silane-modified polyether resin A, 10-20 parts of silane-modified polyether resin B, 2-5 parts of amino-containing silane coupling agent, 0.1-0.5 parts of catalyst, 1-2 parts of epoxy curing agent A, 0.5-1 parts of homemade epoxy curing agent B, 0.1-0.5 parts of water absorbent, 1-3 parts of first auxiliary agent, 0.01-0.03 parts of color paste and 50-70 parts of first thermal conductive filler;

[0013] Component B includes the following raw materials in parts by weight:

[0014] 10-20 parts of epoxy resin, 5-10 parts of homemade epoxy resin B, 5-10 parts of active diluent, 50-70 parts of second thermal conductive filler, 0.1-1 part of second auxiliary agent, 0.01-0.03 parts of color paste and 1-1.5 parts of deionized water.

[0015] Preferably, in the component A of the above-mentioned IPN multi-element thermal conductive structural adhesive, the structure of the silane-modified polyether resin A is:

[0016]

[0017] The structure of the silane-modified polyether resin B is:

[0018]

[0019] Preferably, in the component A of the above-mentioned IPN multi-element thermal conductive structural adhesive, the amino-containing silane coupling agent is any one of aminoethyl-aminopropyltrimethoxysilane, aminopropyltrimethoxysilane, aminopropyltriethoxysilane, and oligomeric aminosilane;

[0020] The catalyst is a chelated organotin catalyst;

[0021] The epoxy curing agent A is a tertiary amine curing agent;

[0022] The water absorbent is vinyl trimethoxy silane;

[0023] The first auxiliary agent includes an antioxidant and a dispersant;

[0024] The first thermally conductive filler is one or more of aluminum oxide, aluminum hydroxide, modified aluminum hydroxide, zinc oxide, aluminum nitride, boron nitride, magnesium oxide, and silicon nitride.

[0025] Preferably, in component A of the above-mentioned IPN multi-element thermally conductive structural adhesive, the homemade epoxy curing agent B is a modified polyetheramine obtained by esterifying hydrogenated dimer acid with methanol to first obtain hydrogenated dimer acid ester, and then aminolyzing the hydrogenated dimer acid ester with polyetheramine diethylene glycol di(3-aminopropyl) ether.

[0026] Preferably, in the above-mentioned IPN multi-element thermal conductive structural adhesive, the epoxy resin A is one or more of bisphenol A epoxy resin, bisphenol F epoxy resin, low-viscosity liquid novolac epoxy resin, and hydrogenated bisphenol A epoxy resin.

[0027] Preferably, in the B component of the above-mentioned IPN multi-element thermal conductive structural adhesive, the active diluent is one or more of LS-692, LS-A part E, LS-622, LS-632, and LS-501;

[0028] The second auxiliary agent is a dispersant;

[0029] The second thermally conductive filler is one or more of aluminum oxide, aluminum hydroxide, modified aluminum hydroxide, zinc oxide, aluminum nitride, boron nitride, magnesium oxide, and silicon nitride.

[0030] Preferably, in the B component of the above-mentioned IPN multi-element thermal conductive structural adhesive, the self-made epoxy resin B is prepared by oxidizing the unsaturated bonds on the long fatty chains in the cardanol glycidyl ether structure with m-chloroperbenzoic acid.

[0031] A method for preparing the high and low temperature resistant and moist heat resistant IPN multi-element thermal conductive structural adhesive of the present invention comprises the following steps:

[0032] According to the formula of the high-low temperature and humidity-resistant IPN multi-element thermal conductive structural adhesive of the present invention, the raw materials of component A and component B are taken to prepare component A and component B respectively;

[0033] Preparation of component A:

[0034] Add the silane-modified polyether resin A, silane-modified polyether resin B, amino-containing silane coupling agent, catalyst, epoxy curing agent A, homemade epoxy curing agent B, water absorbent, first auxiliary agent and color paste in component A into a reaction kettle, stir and disperse at room temperature, the planetary speed is 15-20Hz, the dispersion speed is 500rpm, and vacuum is required during the stirring process; after stirring for 30 minutes, add the first thermal conductive filler, then increase the dispersion speed to 650rpm, and vacuum; stir for 1.5 hours, clean the kettle twice during the period, and degas for 30 minutes after stirring to obtain component A;

[0035] Preparation of component B:

[0036] Add the epoxy resin A, homemade epoxy resin B, active diluent, second auxiliary agent and color paste in component B into the reaction kettle, stir and disperse at room temperature, the planetary speed is 15-20Hz, the dispersion speed is 500rpm, and vacuum is required during the stirring process; after stirring for 30 minutes, add the second thermal conductive filler, then increase the dispersion speed to 650rpm, and vacuum; stir for 1 hour, clean the kettle once during the period, add deionized water, continue stirring and degas for 30 minutes (control at a certain vacuum degree, not too high), and obtain component B;

[0037] The prepared component A and component B are stored in a double tube with a volume ratio of 1:1 at 0.9:1.1-1, thereby forming the high and low temperature resistant and wet heat resistant IPN multi-element thermal conductive structural adhesive as claimed in any one of claims 1 to 7.

[0038] Preferably, the homemade epoxy curing agent B used in component A of the above method is prepared in the following manner:

[0039] 500 parts by weight of methanol and 280 parts by weight of hydrogenated dimer acid were added to a three-necked flask, and 2 parts by weight of concentrated sulfuric acid catalyst were added, and the mixture was refluxed and stirred until a sufficient reaction was achieved, and the solvent was distilled off; saturated sodium bicarbonate was then added, and the mixture was stirred for 30 minutes. The mixture was extracted with ethanol, rinsed with a saturated sodium chloride aqueous solution, and the solvent was rotary evaporated to obtain hydrogenated dimer acid ester; 120 parts by weight of diethylene glycol di(3-aminopropyl) ether was added to the hydrogenated dimer acid ester, and by-products were distilled off under reduced pressure at regular intervals until no diethylene glycol di(3-aminopropyl) ether appeared, and a self-made epoxy curing agent B was obtained after further distillation.

[0040] Preferably, the homemade epoxy resin B used in component B of the above method is prepared in the following manner:

[0041] Add cardanol glycidyl ether into a four-necked flask, stir at a constant temperature of 40-50°C, add a certain proportion of m-chloroperbenzoic acid in dichloromethane solution dropwise, continue to react at a constant temperature of 40-50°C for 2 hours, and then cool to room temperature; wash with saturated sodium carbonate solution until neutral, separate the organic phase, and perform reduced pressure rotary evaporation under vacuum conditions when the temperature is maintained at 60°C to evaporate the water in the organic phase, and filter to obtain the homemade epoxy resin B.

[0042] Compared with the prior art, the high and low temperature resistant and moist heat resistant IPN multi-element thermal conductive structural adhesive and its preparation method provided by the present invention have the following beneficial effects:

[0043] By introducing high-strength, water-resistant epoxy resin and high-flexibility, high-temperature-resistant siloxane bonds into the system, the bonding strength of the thermally conductive structural adhesive to metal substrates, PET, plastics and other substrates can be effectively improved, while greatly improving the high and low temperature resistance to moisture and heat. Compared with ordinary polyurethane thermally conductive structural adhesives, it still has excellent bonding strength under high temperature conditions, with almost no attenuation. In the present invention, two silane-modified polyether resins are added, trimethoxy-terminated silane-modified polyether resin and dimethoxy-terminated silane-modified polyether resin, which can control the reaction speed on the one hand and adjust the strength on the other hand, and flexibly adjust the performance through the proportion of the two.

[0044] Epoxy adhesives are prone to debonding in high temperature and high humidity environments. To address this defect, a modified multi-epoxy epoxy resin was prepared. By increasing the epoxy group, the degree of crosslinking was increased. At the same time, the long unsaturated fatty side chain of cardanol was introduced into the epoxy cured product to reduce stress, improve the bonding performance of the epoxy resin cured product, and improve the high and low temperature and humidity heat resistance. On the other hand, a modified epoxy curing agent-modified polyether amine was prepared, and a rigid structure was introduced into the system to increase the heat resistance and mechanical strength of the cured product. By adding dispersants and active diluents, the viscosity was reduced and good construction performance was maintained. At the same time, the active diluent can also participate in the reaction to avoid the attenuation of strength and high and low temperature and humidity heat aging resistance caused by plasticization. DETAILED DESCRIPTION

[0045] The following is a clear and complete description of the technical solutions in the embodiments of the present invention in combination with the specific content of the present invention; it is obvious that the described embodiments are only part of the embodiments of the present invention, not all of the embodiments, which does not constitute a limitation of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the protection scope of the present invention.

[0046] First, the terms that may be used in this article are explained as follows:

[0047] The term “and / or” means that either or both of them can be realized at the same time. For example, X and / or Y means both “X” or “Y” and “X and Y”.

[0048] The terms "include", "comprises", "contains", "has" or other descriptions with similar semantics should be interpreted as non-exclusive inclusion. For example, including certain technical feature elements (such as raw materials, components, ingredients, carriers, dosage forms, materials, dimensions, parts, components, mechanisms, devices, steps, procedures, methods, reaction conditions, processing conditions, parameters, algorithms, signals, data, products or products, etc.) should be interpreted as including not only certain technical feature elements explicitly listed, but also other technical feature elements known in the art that are not explicitly listed.

[0049] The term "consisting of..." means excluding any technical feature elements not explicitly listed. If this term is used in a claim, it will make the claim closed, so that it does not contain technical feature elements other than the technical feature elements explicitly listed, except for the conventional impurities related to them. If this term only appears in a clause of a claim, it only limits the elements explicitly listed in the clause, and the elements recorded in other clauses are not excluded from the overall claim.

[0050] The term "parts by mass" refers to the mass ratio relationship between multiple components. For example, if it is described that component X is x parts by mass and component Y is y parts by mass, then the mass ratio of component X to component Y is x:y. 1 part by mass can represent any mass, for example, 1 part by mass can be represented as 1 kg or 3.1415926 kg. The sum of the parts by mass of all components is not necessarily 100 parts, but can be greater than 100 parts, less than 100 parts or equal to 100 parts. Unless otherwise specified, the parts, proportions and percentages described herein are all measured by mass.

[0051] When concentration, temperature, pressure, size or other parameters are expressed in the form of a numerical range, the numerical range should be understood to specifically disclose all ranges formed by the pairing of any upper limit, lower limit, and preferred value in the numerical range, regardless of whether the range is explicitly stated; for example, if a numerical range of "2 to 8" is stated, the numerical range should be interpreted as including ranges such as "2 to 7", "2 to 6", "5 to 7", "3 to 4 and 6 to 7", "3 to 5 and 7", "2 and 5 to 7", etc. Unless otherwise specified, the numerical ranges stated herein include both their end values ​​and all integers and fractions within the numerical range.

[0052] The scheme provided by the present invention is described in detail below. The contents not described in detail in the embodiments of the present invention belong to the prior art known to professionals in the field. If the specific conditions are not specified in the embodiments of the present invention, they are carried out according to the conventional conditions in the field or the conditions recommended by the manufacturer. If the manufacturers are not specified in the reagents or instruments used in the embodiments of the present invention, they are all conventional products that can be purchased commercially.

[0053] The embodiment of the present invention provides an IPN multi-component thermal conductive structural adhesive resistant to high and low temperature and humidity. The IPN multi-component thermal conductive structural adhesive is a two-component A and B, and the A component and the B component are used in a volume ratio of 0.9:1.1-1, wherein:

[0054] Component A includes the following raw materials in parts by weight: 10-20 parts of silane-modified polyether resin A, 10-20 parts of silane-modified polyether resin B, 2-5 parts of amino-containing silane coupling agent, 0.1-0.5 parts of catalyst, 1-2 parts of epoxy curing agent A, 0.5-1 parts of homemade epoxy curing agent B, 0.1-0.5 parts of water absorbent, 1-3 parts of first auxiliary agent, 0.01-0.03 parts of color paste, and 50-70 parts of thermal conductive filler;

[0055] Component B includes the following raw materials in parts by weight: 10-20 parts of epoxy resin A, 5-10 parts of homemade epoxy resin B, 5-10 parts of active diluent, 50-70 parts of thermal conductive filler, 0.1-1 part of second auxiliary agent, 0.01-0.03 parts of color paste, and 1-1.5 parts of water.

[0056] Preferably, the structure of the silane-modified polyether resin A used in the above-mentioned component A is:

[0057]

[0058] The structure of the silane-modified polyether resin B is:

[0059]

[0060] Preferably, in the above-mentioned component A, the amino-containing silane coupling agent is any one of aminoethyl-aminopropyltrimethoxysilane, aminopropyltrimethoxysilane, aminopropyltriethoxysilane and oligomeric aminosilane.

[0061] Preferably, in the above-mentioned component A, the catalyst is a chelated organotin catalyst.

[0062] Preferably, in the above-mentioned component A, the epoxy curing agent A is a tertiary amine curing agent.

[0063] Preferably, in the above-mentioned component A, the epoxy curing agent B is prepared by esterifying hydrogenated dimer acid with methanol to first obtain hydrogenated dimer acid ester, and then subjecting the intermediate hydrogenated dimer acid ester to aminolysis reaction with polyetheramine diethylene glycol di(3-aminopropyl) ether, to obtain a modified polyetheramine.

[0064] Preferably, in the above-mentioned component A, the water absorbent is vinyltrimethoxysilane.

[0065] Preferably, in the above-mentioned component A, the first auxiliary agent includes an antioxidant and a dispersant.

[0066] Preferably, in the above-mentioned component A, the first thermally conductive filler includes one or more of aluminum oxide, aluminum hydroxide, modified aluminum hydroxide, zinc oxide, aluminum nitride, boron nitride, magnesium oxide, and silicon nitride.

[0067] Preferably, in the above-mentioned component B, the epoxy resin A includes one or more of bisphenol A epoxy resin, bisphenol F epoxy resin, low-viscosity liquid novolac epoxy resin, and hydrogenated bisphenol A epoxy resin.

[0068] Preferably, in the above-mentioned component B, the self-made epoxy resin B is prepared by oxidizing the unsaturated bonds on the long fatty chains in the structure of cardanol glycidyl ether with m-chloroperbenzoic acid, and is a polyepoxy cardanol glycidyl ether.

[0069] Preferably, in the above-mentioned component B, the active diluent includes one or more of LS-692, LS-A part E, LS-622, LS-632, and LS-501.

[0070] Preferably, in the above-mentioned component B, the second auxiliary agent is a dispersant.

[0071] Preferably, in the above-mentioned component B, the first thermally conductive filler includes one or more of aluminum oxide, aluminum hydroxide, modified aluminum hydroxide, zinc oxide, aluminum nitride, boron nitride, magnesium oxide, and silicon nitride.

[0072] The embodiment of the present invention also provides a method for preparing the above-mentioned high and low temperature resistant and wet heat resistant IPN multi-element thermal conductive structural adhesive, comprising the following steps:

[0073] Take the raw materials of component A and component B according to the above formula to prepare component A and component B respectively;

[0074] Preparation of component A:

[0075] Silane-modified polyether resin A, silane-modified polyether resin B, amino-containing silane coupling agent, catalyst, epoxy curing agent A, self-made epoxy curing agent B, water absorbent, first auxiliary agent and color paste are added to a reaction kettle, stirred and dispersed at room temperature, the planetary speed is 15-20Hz, the dispersion speed is 500rpm, and vacuum is required during the stirring process; after stirring for 30 minutes, a thermal conductive filler is added, and then the dispersion speed is increased to 650rpm, and vacuum is drawn; stirring for 1.5 hours, during which the kettle is cleaned twice, and degassing is performed for 30 minutes after the stirring is completed, thereby obtaining component A;

[0076] Preparation of component B:

[0077] Epoxy resin A, homemade epoxy resin B, active diluent, second auxiliary agent and color paste are added to a reaction kettle, stirred and dispersed at room temperature, the planetary speed is 15-20Hz, the dispersion speed is 500rpm, and vacuum is required during the stirring process; after stirring for 30 minutes, a thermal conductive filler is added, and then the dispersion speed is increased to 650rpm, and vacuum is drawn; stirring for 1 hour, during which the kettle is cleaned once, deionized water is added, stirring is continued and degassing is performed for 30 minutes, and the vacuum pressure is controlled to be ≤-0.09MPa during the degassing process, thereby obtaining component B;

[0078] After component A and component B are prepared separately, they are stored in a 1:1 double tube according to a volume ratio of 0.9:1.1-1, thus forming the above-mentioned high and low temperature resistant and wet heat resistant IPN multi-element thermal conductive structural adhesive.

[0079] In the above method, the homemade epoxy curing agent B used in component A is prepared in the following manner:

[0080] Add 500 parts by weight of methanol and 280 parts by weight of hydrogenated dimer acid into a suitable three-necked flask, add 2 parts by weight of concentrated sulfuric acid catalyst, reflux and stir until fully reacted, and distill off the solvent. Then add saturated sodium bicarbonate, stir for 30 minutes, extract with ethanol, rinse with saturated sodium chloride aqueous solution, and rotary evaporate the solvent to obtain hydrogenated dimer acid ester. Add 120 parts by weight of diethylene glycol di(3-aminopropyl) ether to the hydrogenated dimer acid ester, and distill off the by-products under reduced pressure at regular intervals until diethylene glycol di(3-aminopropyl) ether does not appear, and further distill to obtain the homemade epoxy curing agent B.

[0081] In the above method, the homemade epoxy resin B used in component B is prepared in the following manner:

[0082] Add cardanol glycidyl ether to an appropriate four-necked flask, stir at a constant temperature of 40-50°C, dropwise add 0.1-0.2 mol / L m-chloroperbenzoic acid in dichloromethane solution, continue the constant temperature reaction at 40-50°C for 2 hours, and then cool to room temperature. Wash with saturated sodium carbonate solution until neutral, separate the organic phase, perform vacuum rotary evaporation when the temperature is maintained at about 60°C under vacuum conditions, evaporate the water in the organic phase, and filter to obtain the homemade epoxy resin B.

[0083] From the above, it can be seen that the high-low temperature and wet heat resistant IPN multi-element thermal conductive structural adhesive of the embodiment of the present invention can effectively improve the bonding strength of the thermal conductive structural adhesive to metal substrates, PET, plastics and other substrates by introducing high-strength, water-resistant epoxy resins and high-flexibility, high-temperature resistant siloxy bonds into the system, and at the same time greatly improve the high-low temperature and wet heat resistance. Compared with ordinary polyurethane thermal conductive structural adhesives, it still has excellent bonding strength under high temperature conditions, with almost no attenuation. In the present invention, two silane-modified polyether resins are added, trimethoxy-terminated silane-modified polyether resins are matched with dimethoxy-terminated silane-modified polyether resins, which can control the reaction speed on the one hand and adjust the strength on the other hand, and flexibly adjust the performance through the proportion of the two.

[0084] Epoxy adhesives are prone to debonding in high temperature and high humidity environments. To address this defect, a modified multi-epoxy epoxy resin was prepared. By increasing the epoxy group, the degree of crosslinking was increased. At the same time, the long unsaturated fatty side chain of cardanol was introduced into the epoxy cured product to reduce stress, improve the bonding performance of the epoxy resin cured product, and improve the high and low temperature and humidity heat resistance. On the other hand, a modified epoxy curing agent-modified polyether amine was prepared, and a rigid structure was introduced into the system to increase the heat resistance and mechanical strength of the cured product. By adding dispersants and active diluents, the viscosity was reduced and good construction performance was maintained. At the same time, the active diluent can also participate in the reaction to avoid the attenuation of strength and high and low temperature and humidity heat aging resistance caused by plasticization.

[0085] In order to more clearly demonstrate the technical solution and technical effects provided by the present invention, the solution provided by the embodiment of the present invention is described in detail with specific embodiments below.

[0086] Example 1

[0087] This embodiment provides a high and low temperature resistant and moist heat resistant IPN multi-element thermal conductive structural adhesive, and its preparation method comprises the following steps (each raw material is calculated by weight):

[0088] a. Preparation of homemade epoxy curing agent B:

[0089] Add 500 parts of methanol and 280 parts of hydrogenated dimer acid to an appropriate three-necked flask, add 2 parts of concentrated sulfuric acid catalyst, reflux and stir until fully reacted, and distill off the solvent. Then add saturated sodium bicarbonate, stir for 30 minutes, extract with ethanol, rinse with saturated sodium chloride aqueous solution, and rotary evaporate the solvent to obtain hydrogenated dimer acid ester. Add 120 parts of diethylene glycol di(3-aminopropyl) ether to the hydrogenated dimer acid ester, and distill off the by-products under reduced pressure at regular intervals until diethylene glycol di(3-aminopropyl) ether does not appear, and further distill to obtain a homemade epoxy curing agent.

[0090] b. Preparation of homemade epoxy resin B:

[0091] Add 100 parts of cardanol glycidyl ether to an appropriate four-necked flask, stir at a constant temperature of 40-50°C, dropwise add 0.1-0.2 mol / L m-chloroperbenzoic acid in dichloromethane solution, continue the constant temperature reaction at 40-50°C for 2 hours, and then cool to room temperature. Wash with an appropriate amount of saturated sodium carbonate solution until neutral, separate the organic phase, perform vacuum rotary evaporation when the temperature is maintained at about 60°C under vacuum conditions, evaporate the water in the organic phase, and filter to obtain the homemade epoxy resin.

[0092] c. Preparation of component A:

[0093] 13 parts of silane-modified polyether resin SAX750, 15 parts of silane-modified polyether resin SAX520, 3 parts of aminoethyl-aminopropyltrimethoxysilane, 0.3 parts of chelating organic tin catalyst, 1 part of curing agent DMP-30, 0.5 parts of homemade epoxy curing agent, 0.2 parts of water absorbent vinyltrimethoxysilane, 1 part of antioxidant, 0.8 parts of dispersant and 0.02 parts of color paste were added into a reaction kettle, stirred and dispersed at room temperature, the planetary speed was 15-20Hz, the dispersion speed was 500rpm, and vacuum was required during the stirring process; after stirring for 30 minutes, 70 parts of aluminum hydroxide were added, and then the dispersion speed was increased to 650rpm and vacuum was drawn; stirred for 1.5 hours, during which the kettle was cleaned twice, and degassed for 30 minutes after the stirring was completed, thereby obtaining component A;

[0094] d. Preparation of component B:

[0095] 17 parts of bisphenol A epoxy resin, 5 parts of homemade epoxy resin, 5 parts of active diluent LS-622, 0.6 parts of dispersant and 0.015 parts of color paste were added into a reaction kettle, stirred and dispersed at room temperature, the planetary speed was 15-20 Hz, the dispersion speed was 500 rpm, and vacuum was required during the stirring process; after stirring for 30 minutes, 68 parts of aluminum hydroxide were added, and then the dispersion speed was increased to 650 rpm and vacuum was drawn; stirred for 1 hour, during which the kettle was cleaned once, 1.2 parts of deionized water were added, and stirring was continued and degassing was performed for 30 minutes (controlled at a certain vacuum degree, not too high), thereby obtaining component B;

[0096] e. After component A and component B are prepared respectively, they are stored in a 1:1 double tube according to a volume ratio of 1 to 1, thereby obtaining an IPN multi-element thermal conductive structural adhesive that is resistant to high and low temperature and humidity.

[0097] Example 2

[0098] This embodiment provides a high and low temperature resistant and moist heat resistant IPN multi-element thermal conductive structural adhesive, and its preparation method comprises the following steps (each raw material is calculated by weight):

[0099] a. Preparation of homemade epoxy curing agent B:

[0100] Add 500 parts of methanol and 280 parts of hydrogenated dimer acid to an appropriate three-necked flask, add 2 parts of concentrated sulfuric acid catalyst, reflux and stir until fully reacted, and distill off the solvent. Then add saturated sodium bicarbonate, stir for 30 minutes, extract with ethanol, rinse with saturated sodium chloride aqueous solution, and rotary evaporate the solvent to obtain hydrogenated dimer acid ester. Add 120 parts of diethylene glycol di(3-aminopropyl) ether to the hydrogenated dimer acid ester, and distill off the by-products under reduced pressure at regular intervals until diethylene glycol di(3-aminopropyl) ether does not appear, and further distill to obtain a homemade epoxy curing agent.

[0101] b. Preparation of homemade epoxy resin B:

[0102] Add 100 parts of cardanol glycidyl ether to an appropriate four-necked flask, stir at a constant temperature of 40-50°C, dropwise add 0.1-0.2 mol / L m-chloroperbenzoic acid in dichloromethane solution, continue the constant temperature reaction at 40-50°C for 2 hours, and then cool to room temperature. Wash with an appropriate amount of saturated sodium carbonate solution until neutral, separate the organic phase, perform vacuum rotary evaporation when the temperature is maintained at about 60°C under vacuum conditions, evaporate the water in the organic phase, and filter to obtain the homemade epoxy resin.

[0103] c. Preparation of component A:

[0104] 16 parts of silane-modified polyether resin SAX750, 10 parts of silane-modified polyether resin SAX510, 2.5 parts of aminopropyltrimethoxysilane, 0.3 parts of chelating organic tin catalyst, 1.2 parts of curing agent DMP-30, 0.6 parts of homemade epoxy curing agent, 0.2 parts of water absorbent vinyltrimethoxysilane, 1 part of antioxidant, 0.7 parts of dispersant and 0.02 parts of color paste were added into a reactor, stirred and dispersed at room temperature, the planetary speed was 15-20Hz, the dispersion speed was 500rpm, and vacuum was required during the stirring process; after stirring for 30 minutes, 50 parts of aluminum hydroxide and 14 parts of aluminum oxide were added, and then the dispersion speed was increased to 650rpm and vacuum was drawn; stirred for 1.5 hours, during which the reactor was cleaned twice, and degassed for 30 minutes after stirring, thereby obtaining component A;

[0105] d. Preparation of component B:

[0106] 10 parts of bisphenol A epoxy resin, 5 parts of bisphenol F epoxy resin, 6 parts of homemade epoxy resin, 5 parts of active diluent LS-A E, 0.4 parts of dispersant, and 0.015 parts of color paste are added to a reactor, stirred and dispersed at room temperature, the planetary speed is 15-20Hz, the dispersion speed is 500rpm, and vacuum is required during the stirring process; after stirring for 30 minutes, 60 parts of aluminum oxide are added, and then the dispersion speed is increased to 650rpm, and vacuum is drawn; stirring for 1 hour, during which the reactor is cleaned once, 1 part of deionized water is added, and stirring is continued and degassing is performed for 30 minutes (controlled at a certain vacuum degree, not too high), thereby obtaining component B;

[0107] e. After component A and component B are prepared respectively, they are stored in a 1:1 double tube according to a volume ratio of 1 to 1, thereby obtaining an IPN multi-element thermal conductive structural adhesive that is resistant to high and low temperature and humidity.

[0108] Example 3

[0109] This embodiment provides a high and low temperature resistant and moist heat resistant IPN multi-element thermal conductive structural adhesive, and its preparation method comprises the following steps (each raw material is calculated by weight):

[0110] a. Preparation of homemade epoxy curing agent B:

[0111] Add 500 parts of methanol and 280 parts of hydrogenated dimer acid to an appropriate three-necked flask, add 2 parts of concentrated sulfuric acid catalyst, reflux and stir until fully reacted, and distill off the solvent. Then add saturated sodium bicarbonate, stir for 30 minutes, extract with ethanol, rinse with saturated sodium chloride aqueous solution, and rotary evaporate the solvent to obtain hydrogenated dimer acid ester. Add 120 parts of diethylene glycol di(3-aminopropyl) ether to the hydrogenated dimer acid ester, and distill off the by-products under reduced pressure at regular intervals until diethylene glycol di(3-aminopropyl) ether does not appear, and further distill to obtain a homemade epoxy curing agent.

[0112] b. Preparation of homemade epoxy resin B:

[0113] Add 100 parts of cardanol glycidyl ether to an appropriate four-necked flask, stir at a constant temperature of 40-50°C, dropwise add 0.1-0.2 mol / L m-chloroperbenzoic acid in dichloromethane solution, continue the constant temperature reaction at 40-50°C for 2 hours, and then cool to room temperature. Wash with an appropriate amount of saturated sodium carbonate solution until neutral, separate the organic phase, perform vacuum rotary evaporation when the temperature is maintained at about 60°C under vacuum conditions, evaporate the water in the organic phase, and filter to obtain the homemade epoxy resin.

[0114] c. Preparation of component A:

[0115] 10 parts of silane-modified polyether resin MAX602, 16 parts of silane-modified polyether resin SAX590, 2 parts of aminopropyltrimethoxysilane, 0.2 parts of chelating organic tin catalyst, 1 part of curing agent DMP-30, 0.6 parts of homemade epoxy curing agent, 0.2 parts of water absorbent vinyltrimethoxysilane, 1 part of antioxidant, 0.8 parts of dispersant and 0.02 parts of color paste were added into a reaction kettle, stirred and dispersed at room temperature, the planetary speed was 15-20Hz, the dispersion speed was 500rpm, and vacuum was required during the stirring process; after stirring for 30 minutes, 70 parts of aluminum hydroxide were added, and then the dispersion speed was increased to 650rpm and vacuum was drawn; stirred for 1.5 hours, during which the kettle was cleaned twice, and degassed for 30 minutes after the stirring was completed, thereby obtaining component A;

[0116] d. Preparation of component B:

[0117] 18 parts of bisphenol A epoxy resin, 5 parts of homemade epoxy resin, 6 parts of active diluent LS-A E, 0.35 parts of dispersant, and 0.02 parts of color paste are added to a reactor, stirred and dispersed at room temperature, the planetary speed is 15-20Hz, the dispersion speed is 500rpm, and vacuum is required during the stirring process; after stirring for 30 minutes, 65 parts of aluminum hydroxide are added, and then the dispersion speed is increased to 650rpm, and vacuum is drawn; stirring for 1 hour, during which the reactor is cleaned once, 1 part of deionized water is added, and stirring is continued and degassing is performed for 30 minutes (controlled at a certain vacuum degree, not too high), thereby obtaining component B;

[0118] e. After component A and component B are prepared respectively, they are stored in a 1:1 double tube according to a volume ratio of 1 to 1, thereby obtaining an IPN multi-element thermal conductive structural adhesive that is resistant to high and low temperature and humidity.

[0119] Performance Testing

[0120] The following performance tests were performed on the high and low temperature resistant and wet heat resistant IPN multi-element thermal conductive structural adhesives prepared in Examples 1, 2, and 3 of the present invention respectively:

[0121] Mixed viscosity: Determined according to GB / T 2794-2013 "Determination of viscosity of adhesives - Single cylinder rotational viscometer method".

[0122] Shear strength / 3003 aluminum: Determined in accordance with GB / T 7124-2008 "Determination of tensile shear strength of adhesives (rigid material to rigid material)".

[0123] High temperature shear strength / 3003 aluminum: At a temperature of 60°C, measured in accordance with GB / T 7124-2008 "Determination of tensile shear strength of adhesives (rigid material to rigid material)".

[0124] Tensile strength and elongation at break: measured in accordance with GB / T 528-2008 “Determination of tensile stress-strain properties of vulcanized rubber or thermoplastic rubber”.

[0125] High temperature and high humidity: Test according to GB / T 2423.50 "Environmental testing Part 2: Test method Test Cy constant humidity and heat is mainly used for accelerated testing of components", and the test is 1000h.

[0126] Thermal shock: Tested according to GB / T 2423.22 Environmental testing Part 2: Test method Test N: Temperature change, test for 1000h.

[0127] Thermal conductivity: Determined according to GB / T3399-1982 "Test method for thermal conductivity of plastics - Guarded hot plate method".

[0128] Table 1 is a performance test table of the products in each embodiment

[0129]

[0130] As can be seen from Table 1 above, the IPN multi-element thermal conductive structural adhesive has good thermal conductivity, and the thermal conductivity meets the actual use requirements. It also has excellent flame retardancy and can pass V0; the mixed viscosity is suitable, it has good operating performance, and it has suitable thixotropic properties to meet construction requirements; the shear strength, tensile strength, and elongation at break are all high, and the comprehensive mechanical properties are higher than the current level of thermal conductive structural adhesives on the market, and it has good bonding strength to aluminum substrates, and the body strength and toughness are also good; it has strong high temperature resistance, and the shear strength attenuation is low at high temperatures, and it can still maintain high bonding performance; after 1000h double 85 aging or 1000h hot and cold shock, the strength is almost unchanged, and it has good weather resistance and resistance to high and low temperature wet heat aging. In summary, the invention can effectively meet the requirements for thermal conductive structural adhesives for power batteries.

[0131] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by any technician familiar with the technical field within the technical scope disclosed in the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims. The information disclosed in the background technology section of this article is only intended to deepen the understanding of the overall background technology of the present invention, and should not be regarded as an admission or in any form that the information constitutes prior art known to those skilled in the art.

Claims

1. A high and low temperature resistant and moist heat resistant IPN multi-element thermal conductive structural adhesive, characterized in that: The IPN multi-component thermal conductive structural adhesive is composed of component A and component B in a volume ratio of 0.9:1.1-1; wherein, Component A includes the following raw materials in parts by weight: 10-20 parts of silane-modified polyether resin A, 10-20 parts of silane-modified polyether resin B, 2-5 parts of amino-containing silane coupling agent, 0.1-0.5 parts of catalyst, 1-2 parts of epoxy curing agent A, 0.5-1 parts of homemade epoxy curing agent B, 0.1-0.5 parts of water absorbent, 1-3 parts of first auxiliary agent, 0.01-0.03 parts of color paste and 50-70 parts of first thermal conductive filler; Component B includes the following raw materials in parts by weight: 10-20 parts of epoxy resin, 5-10 parts of homemade epoxy resin B, 5-10 parts of active diluent, 50-70 parts of second thermal conductive filler, 0.1-1 part of second auxiliary agent, 0.01-0.03 parts of color paste and 1-1.5 parts of deionized water.

2. The high and low temperature resistant and moist heat resistant IPN multi-element thermal conductive structural adhesive according to claim 1, characterized in that: In the A component, the structure of the silane-modified polyether resin A is: The structure of the silane-modified polyether resin B is:

3. The high and low temperature resistant and moist heat resistant IPN multi-element thermal conductive structural adhesive according to claim 1, characterized in that: In the component A, the amino-containing silane coupling agent is any one of aminoethyl-aminopropyltrimethoxysilane, aminopropyltrimethoxysilane, aminopropyltriethoxysilane, and oligomeric aminosilane; The catalyst is a chelated organotin catalyst; The epoxy curing agent A is a tertiary amine curing agent; The water absorbent is vinyl trimethoxy silane; The first auxiliary agent includes an antioxidant and a dispersant; The first thermally conductive filler is one or more of aluminum oxide, aluminum hydroxide, modified aluminum hydroxide, zinc oxide, aluminum nitride, boron nitride, magnesium oxide, and silicon nitride.

4. The high and low temperature resistant and moist heat resistant IPN multi-element thermal conductive structural adhesive according to any one of claims 1 to 3, characterized in that: In the component A, the self-made epoxy curing agent B is prepared by esterifying hydrogenated dimer acid with methanol to obtain hydrogenated dimer acid ester first, and then aminolyzing hydrogenated dimer acid ester with polyetheramine diethylene glycol di(3-aminopropyl) ether to obtain modified polyetheramine.

5. The high and low temperature resistant and moist heat resistant IPN multi-element thermal conductive structural adhesive according to any one of claims 1 to 3, characterized in that: The epoxy resin A is one or more of bisphenol A epoxy resin, bisphenol F epoxy resin, low-viscosity liquid novolac epoxy resin, and hydrogenated bisphenol A epoxy resin.

6. The high and low temperature resistant and moist heat resistant IPN multi-element thermal conductive structural adhesive according to any one of claims 1 to 3, characterized in that: In the B component, the active diluent is one or more of LS-692, LS-A part E, LS-622, LS-632, and LS-501; The second auxiliary agent is a dispersant; The second thermally conductive filler is one or more of aluminum oxide, aluminum hydroxide, modified aluminum hydroxide, zinc oxide, aluminum nitride, boron nitride, magnesium oxide, and silicon nitride.

7. The high and low temperature resistant and moist heat resistant IPN multi-element thermal conductive structural adhesive according to any one of claims 1 to 3, characterized in that: In the B component, the self-made epoxy resin B is prepared by oxidizing the unsaturated bonds on the long fatty chain in the structure of cardanol glycidyl ether with m-chloroperbenzoic acid.

8. A method for preparing the high and low temperature resistant and wet heat resistant IPN multi-element thermal conductive structural adhesive according to any one of claims 1 to 7, characterized in that: The following steps are involved: According to the formula of the high and low temperature resistant and moist heat resistant IPN multi-element thermal conductive structural adhesive according to any one of claims 1 to 7, the raw materials of component A and component B are taken to prepare component A and component B respectively; Preparation of component A: Add the silane-modified polyether resin A, silane-modified polyether resin B, amino-containing silane coupling agent, catalyst, epoxy curing agent A, homemade epoxy curing agent B, water absorbent, first auxiliary agent and color paste in component A into a reaction kettle, stir and disperse at room temperature, the planetary speed is 15-20Hz, the dispersion speed is 500rpm, and vacuum is required during the stirring process; after stirring for 30 minutes, add the first thermal conductive filler, then increase the dispersion speed to 650rpm, and vacuum; Stir for 1.5 hours, clean the kettle twice during the period, and degas for 30 minutes after the stirring is completed to obtain component A; Preparation of component B: Add the epoxy resin A, homemade epoxy resin B, active diluent, second auxiliary agent and color paste in component B into the reaction kettle, stir and disperse at room temperature, the planetary speed is 15-20Hz, the dispersion speed is 500rpm, and vacuum is required during the stirring process; after stirring for 30 minutes, add the second thermal conductive filler, then increase the dispersion speed to 650rpm, and vacuum; stir for 1 hour, clean the kettle once during the period, add deionized water, continue stirring and degas for 30 minutes, and control the vacuum pressure ≤-0.09MPa during the degassing process, so as to obtain component B; The prepared component A and component B are stored in a double tube with a volume ratio of 1:1 at 0.9:1.1-1, thereby forming the high and low temperature resistant and wet heat resistant IPN multi-element thermal conductive structural adhesive as claimed in any one of claims 1 to 7.

9. The method for preparing the high and low temperature resistant and moist heat resistant IPN multi-element thermal conductive structural adhesive according to claim 8, characterized in that: The homemade epoxy curing agent B used in component A of the method is prepared in the following manner: 500 parts by weight of methanol and 280 parts by weight of hydrogenated dimer acid were added to a three-necked flask, and 2 parts by weight of concentrated sulfuric acid catalyst were added, and the mixture was refluxed and stirred until a sufficient reaction was achieved, and the solvent was distilled off; saturated sodium bicarbonate was then added, and the mixture was stirred for 30 minutes. The mixture was extracted with ethanol, rinsed with a saturated sodium chloride aqueous solution, and the solvent was rotary evaporated to obtain hydrogenated dimer acid ester; 120 parts by weight of diethylene glycol di(3-aminopropyl) ether was added to the hydrogenated dimer acid ester, and by-products were distilled off under reduced pressure at regular intervals until no diethylene glycol di(3-aminopropyl) ether appeared, and a self-made epoxy curing agent B was obtained after further distillation.

10. The method for preparing the high and low temperature resistant and moist heat resistant IPN multi-element thermal conductive structural adhesive according to claim 8, characterized in that: The homemade epoxy resin B used in the B component of the method is prepared in the following manner: Add cardanol glycidyl ether into a four-necked flask, stir at a constant temperature of 40-50°C, add dropwise a 0.1-0.2 mol / L m-chloroperbenzoic acid dichloromethane solution, continue the constant temperature reaction at 40-50°C for 2 hours, and then cool to room temperature; wash with a saturated sodium carbonate solution until neutral, separate the organic phase, and perform reduced pressure rotary evaporation under vacuum conditions when the temperature is maintained at 60°C to evaporate the water in the organic phase, and filter to obtain the homemade epoxy resin B.

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