Anti-aging silane modified polyether adhesive and preparation method thereof

Abstract

The invention relates to the technical field of adhesives, in particular to an anti-aging silane modified polyether adhesive and a preparation method thereof.The anti-aging silane modified polyether adhesive comprises a component A and a component B. The component A comprises the following raw materials: silane modified polyether resin, a first filler, a curing agent and a silane coupling agent; the component B comprises the following raw materials: epoxy resin, a second filler, a first catalyst and water; the component A or the component B also comprises a tackifier, and the tackifier is prepared from polyol, diisocyanate and a second catalyst. After the prepared anti-aging silane modified polyether adhesive is aged in a high-temperature and high-humidity environment, good adhesive performance between the anti-aging silane modified polyether adhesive and a PET base material can still be kept, and the adhesive force of the anti-aging silane modified polyether adhesive to the PET base material after the anti-aging silane modified polyether adhesive is aged in the high-temperature and high-humidity environment is enhanced; the problem that the adhesive property between an existing silane modified polyether adhesive and a PET base material is reduced after the existing silane modified polyether adhesive is aged in a high-temperature and high-humidity environment is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of adhesives, in particular to an aging-resistant silane-modified polyether adhesive and a preparation method thereof. Background Art

[0002] Silane-modified polyethers are widely used in sealants and adhesives in the construction and automotive sectors due to their solvent-free, low-viscosity, and room-temperature reactivity. Silane-modified polyether adhesives exhibit excellent wettability on most inorganic, metal, and plastic substrates, and also exhibit good adhesion to low-surface-energy substrates such as PET (polyethylene terephthalate). However, existing silane-modified polyether adhesives are susceptible to chemical bond breakage and microcracks after aging in harsh environments (such as high temperature and high humidity). This degrades the adhesive bond with the substrate (particularly PET), posing a risk of debonding and shedding in practical applications. Summary of the Invention

[0003] In response to the problems raised in the background technology, the first purpose of the present invention is to propose an aging-resistant silane-modified polyether adhesive. The prepared aging-resistant silane-modified polyether adhesive can still maintain good bonding performance with the PET substrate after aging in a high-temperature and high-humidity environment, enhance the adhesion of the aging-resistant silane-modified polyether adhesive to the PET substrate after aging in a hot and humid environment, and solve the problem of decreased bonding performance between the existing silane-modified polyether adhesive and the PET substrate after aging in a high-temperature and high-humidity environment.

[0004] The second object of the present invention is to propose a preparation method for the above-mentioned aging-resistant silane-modified polyether adhesive, wherein the prepared aging-resistant silane-modified polyether adhesive can still maintain good bonding performance with the PET substrate after aging in a high-temperature and high-humidity environment, thereby enhancing the adhesion of the aging-resistant silane-modified polyether adhesive to the PET substrate after aging in a hot and humid environment, and solving the problem of decreased bonding performance of existing silane-modified polyether adhesives with the PET substrate after aging in a high-temperature and high-humidity environment.

[0005] To achieve the above objectives, the present invention provides an aging-resistant silane-modified polyether adhesive, comprising a component A and a component B: the component A comprises the following raw materials, in parts by weight: 15 to 40 parts of a silane-modified polyether resin, 40 to 80 parts of a first filler, 1 to 5 parts of a curing agent, and 0.1 to 2 parts of a silane coupling agent; the component B comprises the following raw materials, in parts by weight: 5 to 30 parts of an epoxy resin, 40 to 80 parts of a second filler, 0.5 to 3 parts of a first catalyst, and 0.5 to 2 parts of water; in parts by weight, the component A or the component B further comprises 1 to 6 parts of a tackifier, which is prepared from a polyol, a diisocyanate, and a second catalyst.

[0006] Optionally, the component A includes the following raw materials in parts by weight: 15-40 parts of silane-modified polyether resin, 40-80 parts of a first filler, 1-5 parts of a curing agent, 1-6 parts of a tackifier, and 0.1-2 parts of a silane coupling agent; the component B includes the following raw materials in parts by weight: 5-30 parts of an epoxy resin, 40-80 parts of a second filler, 0.5-3 parts of a first catalyst, and 0.5-2 parts of water.

[0007] Optionally, the component A includes the following raw materials in parts by weight: 15-40 parts of silane-modified polyether resin, 40-80 parts of a first filler, 1-5 parts of a curing agent, and 0.1-2 parts of a silane coupling agent; the component B includes the following raw materials in parts by weight: 5-30 parts of an epoxy resin, 40-80 parts of a second filler, 0.5-3 parts of a first catalyst, 1-6 parts of a tackifier, and 0.5-2 parts of water.

[0008] Optionally, the polyol is one or more of polycaprolactone diol, polyethylene adipate and polyethylene phthalate; the diisocyanate is one or more of diphenylmethane-4,4'-diisocyanate, toluene-2,4-diisocyanate, hexamethylene diisocyanate, dicyclohexylmethane diisocyanate and isophorone diisocyanate.

[0009] Optionally, the molar ratio of the isocyanate group in the diisocyanate to the hydroxyl group in the polyol is (0.1-0.9):1.

[0010] Optionally, the second catalyst is one or more of dibutyltin dilaurate, triethylamine and bismuth neodecanoate; the added amount of the second catalyst is 0.1% to 0.5% of the total added mass of the polyol and the diisocyanate.

[0011] Optionally, the first filler is one or more of calcium carbonate, aluminum hydroxide, aluminum oxide and silicon micropowder; the curing agent is one or more of 2,4,6-tris(dimethylaminomethyl)phenol, benzyldimethylamine and 4,4'-diaminodicyclohexylmethane; the silane coupling agent is one or more of 3-aminopropyltrimethoxysilane, 3-aminopropylmethyldimethoxysilane and N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane; the epoxy resin is one or more of bisphenol A epoxy resin and bisphenol F epoxy resin; the second filler is one or more of calcium carbonate, aluminum hydroxide, aluminum oxide and silicon micropowder; the first catalyst is one or more of dibutyltin dilaurate, dioctyltin dilaurate and chelated tin.

[0012] Optionally, the volume ratio of the component A to the component B is (1~2):1.

[0013] The present invention also proposes a method for preparing an aging-resistant silane-modified polyether adhesive, which is used to prepare the aging-resistant silane-modified polyether adhesive as described in any one of the above, and includes the following steps: step S1, preparing raw materials according to the raw material dosage of component A of the aging-resistant silane-modified polyether adhesive, adding the raw materials of the component A to a reactor, and mixing under vacuum conditions to obtain the component A; step S2, preparing raw materials according to the raw material dosage of component B of the aging-resistant silane-modified polyether adhesive, adding the raw materials of the component B to a reactor, and mixing under vacuum conditions to obtain the component B; step S3, mixing the component A and the component B to obtain the aging-resistant silane-modified polyether adhesive.

[0014] Optionally, the preparation method of the tackifier includes the following steps: step S01, adding the polyol into a reaction vessel and heating it to 90°C~100°C, while vacuuming to remove water; step S02, when the temperature of the reaction system in step S01 is reduced to 50~60°C, adding the diisocyanate and the second catalyst, mixing and heating to 60~80°C, and reacting for 4h~8h; step S03, after the reaction is completed, cooling the reaction system in step S02 and discharging the material to prepare the tackifier.

[0015] Compared with the prior art, the embodiments of the present invention have the following beneficial effects: The aging-resistant silane-modified polyether adhesive of the present invention is prepared by introducing the tackifier into the A component or the B component. The aging-resistant silane-modified polyether adhesive has good initial bonding performance with a PET (polyethylene terephthalate) substrate, and can still maintain good bonding performance with the PET substrate after aging in a high-temperature and high-humidity environment. The adhesion of the aging-resistant silane-modified polyether adhesive to the PET substrate after aging in a hot and humid environment is enhanced, solving the problem of decreased bonding performance of existing silane-modified polyether adhesives with PET substrates after aging in harsh environments (such as high-temperature and high-humidity environments). Among them, hydrogen bonds are formed between the carbamate groups contained in the tackifier and the ester groups in PET to connect the two, thereby enhancing the bonding performance between the aging-resistant silane-modified polyether adhesive and the PET substrate; after aging in a hot and humid environment, an ester exchange reaction will also occur between the carbamate groups contained in the tackifier and the ester groups of PET to produce chemical bonds, which can effectively enhance the bonding performance between the aging-resistant silane-modified polyether adhesive and PET, improve the adhesion of the aging-resistant silane-modified polyether adhesive to the PET substrate after aging in a hot and humid environment, and avoid the risk of debonding or falling off during use. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is an infrared spectrum of the tackifier A of the aging-resistant silane-modified polyether adhesive according to one embodiment of the present invention. DETAILED DESCRIPTION

[0017] For ease of understanding of the present invention, the present invention will be described more fully below. The present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0018] If no specific techniques or conditions are specified in the examples, the experiments were carried out according to the techniques or conditions described in the literature in the field or according to the product instructions. All reagents or instruments used without specifying the manufacturer are commercially available conventional products.

[0019] The present invention provides an aging-resistant silane-modified polyether adhesive, comprising a component A and a component B. The component A comprises the following raw materials, in parts by weight: 15 to 40 parts of a silane-modified polyether resin, 40 to 80 parts of a first filler, 1 to 5 parts of a curing agent, and 0.1 to 2 parts of a silane coupling agent; the component B comprises the following raw materials, in parts by weight: 5 to 30 parts of an epoxy resin, 40 to 80 parts of a second filler, 0.5 to 3 parts of a first catalyst, and 0.5 to 2 parts of water. In parts by weight, the component A or the component B further comprises 1 to 6 parts of a tackifier, which is prepared from a polyol, a diisocyanate, and a second catalyst.

[0020] The aging-resistant silane-modified polyether adhesive of the present invention is prepared by introducing the tackifier into the A component or the B component. The aging-resistant silane-modified polyether adhesive has good initial bonding performance with a PET (polyethylene terephthalate) substrate, and can still maintain good bonding performance with the PET substrate after aging in a high-temperature and high-humidity environment. The adhesion of the aging-resistant silane-modified polyether adhesive to the PET substrate after aging in a hot and humid environment is enhanced, solving the problem of decreased bonding performance of existing silane-modified polyether adhesives with PET substrates after aging in harsh environments (such as high-temperature and high-humidity environments).

[0021] Specifically, the tackifier is prepared from the polyol, the diisocyanate and the second catalyst, and the chemical reaction formula is: ; wherein OCN—R1—NCO represents the diisocyanate, HO—R2—OH represents the polyol, represents the thickener obtained by the reaction, and n represents the degree of polymerization.

[0022] The carbamate groups contained in the tackifier and the ester groups in the PET will form hydrogen bonds to connect the two, thereby enhancing the bonding performance between the aging-resistant silane-modified polyether adhesive and the PET substrate; after aging in a hot and humid environment, an ester exchange reaction will also occur between the carbamate groups contained in the tackifier and the ester groups of the PET to produce a chemical bond, which can effectively enhance the bonding performance between the aging-resistant silane-modified polyether adhesive and the PET, improve the adhesion of the aging-resistant silane-modified polyether adhesive to the PET substrate after aging in a hot and humid environment, and avoid the risk of debonding or falling off during use. The chemical reaction formula is: .

[0023] It is further explained that when preparing the aging-resistant silane-modified polyether adhesive, since the two ends of the tackifier have active hydroxyl groups, the tackifier can react with the silane-modified polyether resin matrix or the epoxy resin matrix. That is, no additional end-capping operation is required when preparing the tackifier, which can reduce the synthesis steps when preparing the tackifier and save production time and cost.

[0024] In one embodiment of the present invention, the component A includes the following raw materials in parts by weight: 15-40 parts of silane-modified polyether resin, 40-80 parts of a first filler, 1-5 parts of a curing agent, 1-6 parts of a tackifier, and 0.1-2 parts of a silane coupling agent; the component B includes the following raw materials in parts by weight: 5-30 parts of an epoxy resin, 40-80 parts of a second filler, 0.5-3 parts of a first catalyst, and 0.5-2 parts of water.

[0025] In another embodiment of the present invention, the component A comprises the following raw materials in parts by weight: 15-40 parts of a silane-modified polyether resin, 40-80 parts of a first filler, 1-5 parts of a curing agent, and 0.1-2 parts of a silane coupling agent; the component B comprises the following raw materials in parts by weight: 5-30 parts of an epoxy resin, 40-80 parts of a second filler, 0.5-3 parts of a first catalyst, 1-6 parts of a tackifier, and 0.5-2 parts of water.

[0026] To further illustrate, the polyol is one or more of polycaprolactone diol, polyethylene adipate and polyethylene phthalate; the diisocyanate is one or more of diphenylmethane-4,4'-diisocyanate (4,4'-MDI), toluene-2,4-diisocyanate (2,4-TDI), hexamethylene diisocyanate (HDI), dicyclohexylmethane diisocyanate (HMDI), and isophorone diisocyanate (IPDI).

[0027] Specifically, the structural formula of R2 can be: 、 and One of them; it can be seen that the structural formula of the prepared tackifier also has an ester group. After aging in a hot and humid environment, an ester exchange reaction will also occur between the ester group contained in the tackifier and the ester group of the PET to produce a chemical bond, which can further enhance the bonding performance between the aging-resistant silane-modified polyether adhesive and the PET, and improve the adhesion of the aging-resistant silane-modified polyether adhesive to the PET substrate after aging in a hot and humid environment, further avoiding the risk of debonding or falling off during use. The chemical reaction formula is: ; wherein R3 can be one of phenyl, butyl and pentyl, and the structural formula of R4 can be one of ethyl, pentyl and ether.

[0028] Specifically, the structural formula of R1 can be 、 、 、 and One of them.

[0029] To further illustrate, the polyol may be selected from one or more of polycaprolactone diol, polyethylene adipate and polyethylene phthalate, and polypropylene glycol or polytetramethylene ether glycol may be added to reduce the viscosity of the prepared tackifier.

[0030] To further illustrate, the molar ratio of the isocyanate group in the diisocyanate to the hydroxyl group in the polyol is (0.1-0.9):1.

[0031] The molar ratio of the isocyanate group in the diisocyanate to the hydroxyl group in the polyol is (0.1-0.9):1, so as to ensure that the terminal groups at both ends of the molecular chain of the tackifier are hydroxyl groups.

[0032] Further, the second catalyst is one or more of dibutyltin dilaurate, triethylamine and bismuth neodecanoate; the added amount of the second catalyst is 0.1% to 0.5% of the total added mass of the polyol and the diisocyanate.

[0033] When the amount of the second catalyst added is too small, the reaction rate between the polyol and the diisocyanate will be insufficient; when the amount of the second catalyst added is too much, it is easy to trigger side reactions, such as the self-polymerization reaction of the diisocyanate or the reaction of the diisocyanate with water to produce urea compounds, thereby causing the performance of the prepared thickener to deteriorate. When the amount of the second catalyst added is too much, the reaction rate will be too fast. If the heat dissipation of the reaction system is not timely, it may cause the thickener to explode during the reaction process, thereby causing the performance of the thickener to deteriorate.

[0034] Further explained, the first filler is one or more of calcium carbonate, aluminum hydroxide, aluminum oxide and silicon powder; the curing agent is one or more of 2,4,6-tris(dimethylaminomethyl)phenol, benzyldimethylamine and 4,4'-diaminodicyclohexylmethane; the silane coupling agent is one or more of 3-aminopropyltrimethoxysilane, 3-aminopropylmethyldimethoxysilane and N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane; the epoxy resin is one or more of bisphenol A epoxy resin and bisphenol F epoxy resin; the second filler is one or more of calcium carbonate, aluminum hydroxide, aluminum oxide and silicon powder; the first catalyst is one or more of dibutyltin dilaurate, dioctyltin dilaurate and chelated tin.

[0035] The first and second fillers help improve the performance of the aging-resistant silane-modified polyether adhesive: calcium carbonate can optimize the heat resistance and hardness of the aging-resistant silane-modified polyether adhesive; aluminum hydroxide and aluminum oxide mainly serve as thermally conductive and flame-retardant fillers, improving the thermal conductivity of the aging-resistant silane-modified polyether adhesive and imparting flame retardancy; silicon micropowder can enhance the mechanical properties and heat resistance of the aging-resistant silane-modified polyether adhesive. The curing agent helps promote the curing reaction of the epoxy resin. The first catalyst helps accelerate the curing reaction of the silane-modified polyether resin.

[0036] To further illustrate, the volume ratio of the component A to the component B is (1~2):1.

[0037] The present invention also proposes a preparation method of an aging-resistant silane-modified polyether adhesive, which is used to prepare the aging-resistant silane-modified polyether adhesive as described in the above-mentioned item, comprising the following steps: step S1, preparing raw materials according to the raw material dosage of component A of the aging-resistant silane-modified polyether adhesive, adding the raw materials of the component A to a reactor, and mixing under vacuum conditions to obtain the component A; step S2, preparing raw materials according to the raw material dosage of component B of the aging-resistant silane-modified polyether adhesive, adding the raw materials of the component B to a reactor, and mixing under vacuum conditions to obtain the component B; step S3, mixing the component A and the component B to obtain the aging-resistant silane-modified polyether adhesive.

[0038] The present invention introduces the tackifier into the component A or the component B of the aging-resistant silane-modified polyether adhesive, and the tackifier is prepared from a polyol, a diisocyanate, and a second catalyst. The urethane group contained in the tackifier forms a hydrogen bond with the ester group of PET to connect the two, so that the prepared aging-resistant silicon-modified polyether adhesive has good initial bonding performance with the PET (polyethylene terephthalate) substrate.

[0039] After the aging-resistant silane-modified polyether adhesive is aged in a high-temperature and high-humidity environment, an ester exchange reaction will occur between the carbamate groups contained in the tackifier and the ester groups of the PET to produce chemical bonds, thereby enhancing the bonding performance between the aging-resistant silane-modified polyether adhesive and the PET, and improving the adhesion of the aging-resistant silane-modified polyether adhesive to the PET substrate after aging in a hot and humid environment, thereby avoiding debonding or falling off during actual application, and solving the problem of decreased bonding performance between the existing silane-modified polyether adhesive and the PET substrate after aging in harsh environments (such as high-temperature and high-humidity environments).

[0040] It is further explained that when preparing the aging-resistant silane-modified polyether adhesive, since the two ends of the tackifier have active hydroxyl groups, the tackifier can react with the silane-modified polyether resin matrix or the epoxy resin matrix. That is, the tackifier does not need to be additionally capped, which can reduce the synthesis steps when preparing the tackifier and save production time and cost.

[0041] To further illustrate, in step S1, the mixing time under the vacuum condition is 1 hour to 2 hours, and in step S2, the mixing time under the vacuum condition is 1 hour to 2 hours.

[0042] To further illustrate, in step S3, the component A and the component B are mixed in a volume ratio of (1-2):1 to obtain an aging-resistant silane-modified polyether adhesive.

[0043] Further explanation: the preparation method of the tackifier includes the following steps: step S01, adding the polyol into a reaction vessel and heating it to 90°C~100°C, while vacuuming to remove water; step S02, when the temperature of the reaction system in step S01 is reduced to 50~60°C, adding the diisocyanate and the second catalyst, mixing and heating to 60~80°C, and reacting for 4h~8h; step S03, after the reaction is completed, cooling the reaction system in step S02 and discharging the material to prepare the tackifier.

[0044] The preparation method of the tackifier of the present invention is simple and efficient, has no pollution such as VOC (volatile organic compounds), and is environmentally friendly.

[0045] To further illustrate, in step S03, after the reaction is completed, the reaction system of step S02 is cooled to 20-40°C and then the material can be discharged to obtain the tackifier.

[0046] To further illustrate, the polyol can be selected from one or more of polycaprolactone diol, polyethylene adipate, and polyethylene phthalate, and polypropylene glycol or polytetramethylene ether glycol can be further added to reduce the viscosity of the prepared tackifier. That is, the prepared tackifier also has ester groups. After aging in a hot and humid environment, the ester groups in the tackifier will undergo an ester exchange reaction with the ester groups of the PET, forming chemical bonds. This can further enhance the bonding performance between the aging-resistant silane-modified polyether adhesive and the PET, improve the adhesion of the aging-resistant silane-modified polyether adhesive to the PET substrate after aging in a hot and humid environment, and further avoid the risk of debonding or shedding.

[0047] (1) Preparation and analysis of tackifier: (1) Preparation of tackifier A: The tackifier was prepared according to the preparation method of the tackifier, wherein the molar ratio of the isocyanate group in the diisocyanate to the hydroxyl group in the polyol was 0.5:1: Step S01: Add polyol [50 g of polypropylene glycol (Dexin Federal DDL-2000D) and 50 g of polycaprolactone diol (Dacelide PCL-2000)] into a reaction vessel, heat to 100° C., and simultaneously evacuate to remove water; Step S02: When the temperature of the reaction system in step S01 is lowered to 60° C., 7 g of diisocyanate (diphenylmethane-4,4'-diisocyanate, 4,4'-MDI) and 0.1 g of a second catalyst (dibutyltin dilaurate) are added, mixed, and heated to 80° C. for reaction for 5 hours; Step S03: After the reaction is completed, the reaction system of step S02 is cooled. When the temperature drops to 40° C., the material is discharged to obtain the tackifier A.

[0048] The prepared tackifier A was subjected to infrared spectroscopy analysis, and the results were as follows: Figure 1 As shown: Among them, the wave number is 1732cm -1 The absorption peak at is attributed to the carbonyl group on the carbamate and polyester in the chemical structure of the tackifier, and Figure 1 Medium 2200cm -1 There is no absorption peak nearby, which proves that the isocyanate has been completely reacted and the tackifier is successfully obtained.

[0049] (2) Preparation of thickeners B~D: Thickeners B to D differ from thickener A in the selection of raw materials and the amount of raw materials added, as well as the reaction conditions during the preparation process. The other steps are the same as the preparation method of thickener A. The specific raw material types and addition amounts are as shown in Table 1, and the specific reaction conditions are as shown in Table 2: Table 1 Raw material selection and addition amount of tackifiers A~D .

[0050] Table 2 Reaction conditions of tackifiers A~D .

[0051] (II) Examples 1 to 8: (1) Example 1: The aging-resistant silane-modified polyether adhesive comprises a component A and a component B, wherein the volume ratio of the component A to the component B is 1:1; The component A comprises the following raw materials in parts by weight: 20 parts of silane-modified polyether resin, 50 parts of a first filler (aluminum hydroxide), 3 parts of a tackifier (the tackifier A), 5 parts of a curing agent [2,4,6-tris(dimethylaminomethyl)phenol], and 1 part of a silane coupling agent (3-aminopropyltrimethoxysilane); The B component includes the following raw materials in parts by weight: 10 parts of epoxy resin (bisphenol A epoxy resin), 50 parts of the second filler (aluminum hydroxide), 0.5 parts of the first catalyst (dibutyltin dilaurate), and 0.5 parts of water; The preparation method of the aging-resistant silane-modified polyether adhesive of Example 1 is as follows: Step S1, preparing raw materials according to the raw material amounts of component A of the aging-resistant silane-modified polyether adhesive, adding a silane-modified polyether resin, a first filler (aluminum hydroxide), a tackifier (the tackifier A), a curing agent [2,4,6-tris(dimethylaminomethyl)phenol], and a silane coupling agent (3-aminopropyltrimethoxysilane) into a reactor, and mixing under vacuum conditions for 1 hour to obtain the component A; Step S2, preparing raw materials according to the raw material amounts of component B of the aging-resistant silane-modified polyether adhesive, adding epoxy resin (bisphenol A epoxy resin), a second filler (aluminum hydroxide), a first catalyst (dibutyltin dilaurate) and water into a reaction kettle, and mixing under vacuum conditions for 1 hour to obtain the component B; Step S3: mixing the component A and the component B in a volume ratio of 1:1 to prepare an aging-resistant silane-modified polyether adhesive.

[0052] (2) Examples 2 to 7: The difference between Examples 2 to 4 and Example 1 is that the amount of each raw material added in component A and component B of the aging-resistant silane-modified polyether adhesive and the volume ratio of component A to component B are different. The remaining preparation steps are the same as those of Example 1. The specific amount of raw materials added is according to Table 3 (the amount added is in parts by weight), and the volume ratio of component A to component B is according to Table 4: Table 3 Amount of raw materials added in Examples 1 to 4 .

[0053] Table 4 Volume ratio of component A and component B in Examples 1 to 4 .

[0054] The difference between Examples 5 to 7 and Example 1 is that the raw materials of component A and component B of the aging-resistant silane-modified polyether adhesive are selected differently. The specific raw material selection is carried out according to Table 5. The addition amount of the raw materials and the preparation steps are the same as those of Example 1: Table 5 Raw material selection of Example 1 and Examples 5 to 7 .

[0055] (3) Example 8: The aging-resistant silane-modified polyether adhesive of Example 8 includes component A and component B, and the volume ratio of component A to component B is 2:1; The component A comprises the following raw materials in parts by weight: 20 parts of silane-modified polyether resin, 50 parts of a first filler (aluminum hydroxide), 5 parts of a curing agent [2,4,6-tris(dimethylaminomethyl)phenol], and 1 part of a silane coupling agent (3-aminopropyltrimethoxysilane); The B component includes the following raw materials in parts by weight: 10 parts of epoxy resin (bisphenol A epoxy resin), 50 parts of second filler (aluminum hydroxide), 0.5 parts of first catalyst (dibutyltin dilaurate), 0.5 parts of water, and 3 parts of tackifier (the tackifier A); The preparation method of the aging-resistant silane-modified polyether adhesive of Example 8 is as follows: Step S1, preparing raw materials according to the raw material amounts of component A of the aging-resistant silane-modified polyether adhesive, adding a silane-modified polyether resin, a first filler (aluminum hydroxide), a curing agent [2,4,6-tris(dimethylaminomethyl)phenol], and a silane coupling agent (3-aminopropyltrimethoxysilane) into a reactor, and mixing under vacuum conditions for 1 hour to obtain the component A; Step S2, preparing raw materials according to the raw material amounts of component B of the aging-resistant silane-modified polyether adhesive, adding epoxy resin (bisphenol A epoxy resin), a second filler (aluminum hydroxide), a first catalyst (dibutyltin dilaurate), a tackifier (the tackifier A) and water to a reactor, and mixing under vacuum for 1 hour to obtain the component B; Step S3: mixing the component A and the component B in a volume ratio of 2:1 to prepare an aging-resistant silane-modified polyether adhesive.

[0056] (III) Comparative Example 1: The difference between Comparative Example 1 and Example 1 is that the tackifier A is not added to component A of the aging-resistant silane-modified polyether adhesive of Comparative Example 1, and the remaining raw materials, addition amounts, and preparation methods are the same as those of Example 1.

[0057] (IV) Performance testing and result analysis: The aging-resistant silane-modified polyether adhesives prepared in Examples 1 to 8 and Comparative Example 1 were subjected to performance tests according to the following method. The test results are shown in Table 6: Test method: (1) Sample preparation: The surfaces of multiple aluminum plates each having a size of 25 mm × 100 mm × 2 mm were cleaned with ethanol. After drying, the plates were bonded using the silane-modified polyether adhesive prepared in Examples 1 to 8 and Comparative Example 1. A piece of PET film was placed between two aluminum plates to form a sandwich structure (i.e., the structure after bonding with the silane-modified polyether adhesive was: aluminum plate-silane-modified polyether adhesive layer-PET film-silane-modified polyether adhesive layer-aluminum plate). The bonding size of the silane-modified polyether adhesive was 12.5 mm × 25 mm × 0.2 mm. The plates were cured at a temperature of 25°C and a humidity of 50% RH for 7 days to prepare the sample.

[0058] (2) Test method for tensile shear strength of double 85 before wet heat aging: clamp the sample prepared above on a fixture, use a tensile testing machine to stretch the sample at a rate of 5 mm / min, and record the curve. The maximum stress during the destruction process is the destruction load F (unit: N), which is calculated by the destruction load F (unit: N) and the bonding area A (unit: mm 2 ) The tensile shear strength δ (unit: MPa) of double 85 before wet heat aging is calculated. The calculation formula is: tensile shear strength δ = failure load F / bonding area A.

[0059] (3) Test method for tensile shear strength after double 85 wet heat aging: Place the cured sample in a wet heat box at 85℃ and 85% RH for 1000 hours, then take out the aged sample and place it in the air for 24 hours under the standard curing environment (25℃, 50% RH). The tensile shear strength after double 85 wet heat aging is tested. The test method is the same as the test method for shear strength before double 85 wet heat aging.

[0060] Table 6 Test results of Examples 1 to 8 and Comparative Example 1 .

[0061] Among them, CF in Table 6 represents the cohesive failure form, and AF represents the interfacial failure form.

[0062] The calculation formula for the tensile shear strength retention rate of double 85 after aging is: tensile shear strength retention rate of double 85 after wet heat aging = tensile shear strength of double 85 after wet heat aging / tensile shear strength of double 85 before wet heat aging × 100%.

[0063] As can be seen from the data in Table 6, the tensile shear strength retention rate of the silane-modified polyether adhesives prepared in Examples 1 to 8 after double 85 degree heat and humidity aging is maintained between 89% and 93%, and the failure mode of the silane-modified polyether adhesive layer is cohesive failure, indicating that the silane-modified polyether adhesive prepared in Example 1 is still relatively strong and has good bonding strength with the substrate interface (the substrate interface includes the bonding interface with the aluminum plate and the bonding interface with the PET film) after heat and humidity aging.

[0064] The tensile shear strength of the silane-modified polyether adhesive prepared in Comparative Example 1 before double 85 wet heat aging was 5.4 MPa, while the tensile shear strength after double 85 wet heat aging was only 3.4 MPa. The tensile shear strength retention rate after double 85 wet heat aging dropped to 63%, which was significantly lower than that of the silane-modified polyether adhesives prepared in Examples 1 to 8. This indicates that the shear strength of the silane-modified polyether adhesive prepared in Comparative Example 1 was severely attenuated after double 85 wet heat aging, and the damage form of the silane-modified polyether adhesive layer was interfacial damage, specifically, the interface between the silane-modified polyether adhesive layer and the PET film was destroyed, which has the risk of debonding and falling off in actual applications.

[0065] The aging-resistant silane-modified polyether adhesive of the present invention is a two-component adhesive (Examples 1 to 7 introduce the tackifier into the A component, and Example 8 introduces the tackifier into the D component). The tackifier is prepared from a polyol, a diisocyanate, and a second catalyst. The urethane group contained in the tackifier forms a hydrogen bond with the ester group of PET to connect the two, so that the prepared aging-resistant silicon-modified polyether adhesive has good initial bonding performance with the PET (polyethylene terephthalate) substrate.

[0066] After the aging-resistant silane-modified polyether adhesive is aged in a high-temperature and high-humidity environment, an ester exchange reaction will occur between the carbamate group contained in the tackifier and the ester group of the PET to produce a chemical bond, thereby enhancing the bonding performance between the aging-resistant silane-modified polyether adhesive and the PET, and improving the adhesion of the aging-resistant silane-modified polyether adhesive to the PET substrate after aging in a hot and humid environment, thereby avoiding debonding or falling off during actual application.

[0067] It is further explained that when preparing the aging-resistant silane-modified polyether adhesive, since the two ends of the tackifier have active hydroxyl groups, the tackifier can react with the resin matrix (i.e., the silane-modified polyether resin or the epoxy resin). That is, the tackifier does not need to be additionally capped, which can reduce the synthesis steps when preparing the tackifier, saving production time and cost.

[0068] The above-described embodiments merely illustrate several implementations of the present invention. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, and all such variations and improvements fall within the scope of protection of the present invention.

Claims

1. An aging-resistant silane-modified polyether adhesive, characterized in that: Including component A and component B: The component A comprises the following raw materials in parts by weight: 15-40 parts of silane-modified polyether resin, 40-80 parts of first filler, 1-5 parts of curing agent and 0.1-2 parts of silane coupling agent; The B component includes the following raw materials in parts by weight: 5-30 parts of epoxy resin, 40-80 parts of second filler, 0.5-3 parts of first catalyst and 0.5-2 parts of water; In parts by weight, the component A or the component B further comprises 1 to 6 parts of a tackifier, which is prepared from a polyol, a diisocyanate and a second catalyst.

2. The aging-resistant silane-modified polyether adhesive according to claim 1, characterized in that: The component A comprises the following raw materials in parts by weight: 15-40 parts of silane-modified polyether resin, 40-80 parts of first filler, 1-5 parts of curing agent, 1-6 parts of tackifier and 0.1-2 parts of silane coupling agent; The B component includes the following raw materials in parts by weight: 5 to 30 parts of epoxy resin, 40 to 80 parts of second filler, 0.5 to 3 parts of first catalyst and 0.5 to 2 parts of water.

3. The aging-resistant silane-modified polyether adhesive according to claim 1, characterized in that: The component A comprises the following raw materials in parts by weight: 15-40 parts of silane-modified polyether resin, 40-80 parts of first filler, 1-5 parts of curing agent and 0.1-2 parts of silane coupling agent; The B component includes the following raw materials in parts by weight: 5-30 parts of epoxy resin, 40-80 parts of second filler, 0.5-3 parts of first catalyst, 1-6 parts of tackifier and 0.5-2 parts of water.

4. The aging-resistant silane-modified polyether adhesive according to claim 1, characterized in that: The polyol is one or more of polycaprolactone diol, polyethylene adipate and polyethylene phthalate; The diisocyanate is one or more of diphenylmethane-4,4'-diisocyanate, toluene-2,4-diisocyanate, hexamethylene diisocyanate, dicyclohexylmethane diisocyanate, and isophorone diisocyanate.

5. The aging-resistant silane-modified polyether adhesive according to claim 1, characterized in that: The molar ratio of the isocyanate group in the diisocyanate to the hydroxyl group in the polyol is (0.1-0.9):

1.

6. The aging-resistant silane-modified polyether adhesive according to claim 1, characterized in that: The second catalyst is one or more of dibutyltin dilaurate, triethylamine and bismuth neodecanoate; the added amount of the second catalyst is 0.1% to 0.5% of the total added mass of the polyol and the diisocyanate.

7. The aging-resistant silane-modified polyether adhesive according to claim 1, characterized in that: The first filler is one or more of calcium carbonate, aluminum hydroxide, aluminum oxide and silicon powder; The curing agent is one or more of 2,4,6-tris(dimethylaminomethyl)phenol, benzyldimethylamine and 4,4'-diaminodicyclohexylmethane; The silane coupling agent is one or more of 3-aminopropyltrimethoxysilane, 3-aminopropylmethyldimethoxysilane and N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane; The epoxy resin is one or more of bisphenol A epoxy resin and bisphenol F epoxy resin; The second filler is one or more of calcium carbonate, aluminum hydroxide, aluminum oxide and silicon powder; The first catalyst is one or more of dibutyltin dilaurate, dioctyltin dilaurate and chelated tin.

8. The aging-resistant silane-modified polyether adhesive according to claim 1, characterized in that: The volume ratio of the component A to the component B is (1~2):

1.

9. A method for preparing an aging-resistant silane-modified polyether adhesive, for preparing the aging-resistant silane-modified polyether adhesive according to any one of claims 1 to 8, characterized in that: The following steps are involved: Step S1, preparing raw materials according to the raw material dosage of component A of the aging-resistant silane-modified polyether adhesive, adding the raw materials of component A into a reactor, and mixing under vacuum conditions to obtain component A; Step S2, preparing raw materials according to the raw material dosage of component B of the aging-resistant silane-modified polyether adhesive, adding the raw materials of component B into a reaction kettle, and mixing under vacuum conditions to obtain component B; Step S3: mixing the component A and the component B to obtain an aging-resistant silane-modified polyether adhesive.

10. The method for preparing the aging-resistant silane-modified polyether adhesive according to claim 9, characterized in that: The preparation method of the tackifier comprises the following steps: Step S01, adding the polyol into a reaction vessel and heating it to 90° C. to 100° C. while vacuuming to remove water; Step S02: When the temperature of the reaction system in step S01 is lowered to 50-60° C., the diisocyanate and the second catalyst are added, mixed, and the temperature is raised to 60-80° C., and the reaction is carried out for 4-8 hours; Step S03: After the reaction is completed, the reaction system of step S02 is cooled and discharged to prepare the tackifier.

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