Epoxy resin adhesive for low temperature and preparation method and use method thereof

Abstract

The present invention discloses an epoxy resin adhesive for low temperature and its preparation method and use method, which belongs to the field of adhesives. The adhesive comprises component A and component B in a ratio of 1.5 to 1.7:1 by mass, wherein component A comprises 10 to 30% SW-70, 10 to 20% E51, 0.1 to 1% defoamer, and the balance is a first filler, and component B comprises 20 to 40% curing agent, 0.1 to 1wt% accelerator, and the balance is a second filler; the filler contains reinforcing fiber and silica. After curing, the adhesive has high hardness and strength, can withstand high weight, still has high modulus and strength at low temperatures, and has strong impact resistance; can be cured at room temperature or even lower temperatures, has good bonding performance at low temperatures, has a moderate curing rate, and has a moderate construction time, which solves the problem of short construction time; the adhesive has thixotropic properties and can be used in places where flowable adhesives cannot be used.

Description

Technical Field

[0001] The invention relates to an epoxy resin adhesive for low temperature and a preparation method and a use method thereof, belonging to the field of adhesives. Background Art

[0002] Liquefied petroleum gas (LPG) is a high-calorific, clean secondary energy source that requires low-temperature storage. Its use is increasing, and LPG is currently primarily transported via carriers. Adhesives used on LPG vessels require excellent low-temperature resistance and mechanical properties. Epoxy resin adhesives are commonly used for bonding LPG vessels due to their low cure shrinkage and excellent creep properties.

[0003] However, the compressive strength and impact resistance of LPG epoxy resin are still at a relatively low level. At the same time, in ultra-low temperature environments, the mechanical properties of epoxy resin glue will decrease, which can easily cause the material to break. Summary of the Invention

[0004] In order to overcome the deficiencies of the prior art, the present invention provides an epoxy resin adhesive for low temperature use, which still has high compressive strength in a low temperature environment, and provides a preparation method and a use method of the epoxy resin adhesive.

[0005] The technical solution adopted by the present invention to solve its technical problem is:

[0006] In a first aspect, the present application provides an epoxy resin adhesive for low temperature, comprising component A and component B, wherein the working ratio of component A to component B is 1.5-1.7:1 by mass;

[0007] The component A includes SW-70 10wt%~30wt%, E51 10wt%~20wt%, defoamer 0.1wt%~1wt%, and the balance is the first filler;

[0008] The B component includes 20 wt% to 40 wt% of a diamine curing agent, 0.1 wt% to 1 wt% of a curing accelerator, and the balance is a second filler;

[0009] The first filler contains reinforcing fiber, and both the first filler and the second filler contain silicon dioxide.

[0010] The epoxy resin adhesive for low temperatures provided in this application is green and environmentally friendly and has high compressive strength. As a solvent-free adhesive that can adapt to working in LPG environments, this product introduces IPN (interpenetrating polymer network) technology to maintain the high strength of the epoxy resin; the raw material formula makes the epoxy resin have high thixotropy.

[0011] Furthermore, the reinforcing fiber is bacterial cellulose, and the mass ratio of silica to bacterial cellulose in the first filler is 4-5.5:2. The bacterial cellulose helps build a three-dimensional network structure within the epoxy matrix, significantly improving shear resistance and compressive modulus. The optimized ratio helps ensure the uniformity of the interconnected network, balancing toughness and strength.

[0012] Bacterial cellulose builds a three-dimensional network structure in the epoxy matrix, disperses the load through physical cross-linking, effectively inhibits the yielding of the matrix and the generation of microcracks, thereby improving the shear properties and compressive modulus of the material.

[0013] Furthermore, the second filler further contains heavy calcium, and the particle size of the heavy calcium is smaller than that of the silicon dioxide; in the second filler, the mass ratio of the silicon dioxide to the heavy calcium is 4-5:1.

[0014] The combination of heavy calcium and silicon dioxide helps to make the cured resin denser and improve the compressive strength and compressive modulus.

[0015] Furthermore, the silicon dioxide in the first filler is 1250 mesh silicon dioxide, and the silicon dioxide in the second filler is 1250 mesh silicon dioxide, which is beneficial to improving hardness, compressive strength and thixotropy.

[0016] 1250 mesh silica is a micron-sized filler with a moderate particle size. It can provide sufficient physical support to effectively improve the hardness and compressive strength of the adhesive, and can also make the adhesive have a certain thixotropy to meet the use requirements in specific construction scenarios.

[0017] Furthermore, in the component A, the mass ratio of the SW-70 to the E51 is 1-4:2; and the diamine curing agent is 4'4-diaminodiphenylmethane.

[0018] Controlling the ratio of SW-70 to E51 optimizes the IPN effect and overall performance. The DDM (4'4-diaminodiphenylmethane) curing agent, containing a rigid benzene ring structure, synergizes with SW-70 to enhance cured strength. DDM's high reactivity allows it to form a high-density crosslink network with SW-70. When mixed with E51 in a ratio of 1:4:2, SW-70 leverages the high strength provided by the high crosslinking degree of SW-70 and the excellent bonding properties of E51. The resulting IPN effect further enhances the adhesive's overall mechanical properties. As a diamine curing agent, DDM works in conjunction with the rigid benzene ring structure of SW-70 to increase the crosslink density and rigidity of the epoxy resin, enabling the adhesive to maintain high modulus and strength even at low temperatures, creating a synergistic effect between the resins.

[0019] Furthermore, the curing accelerator is DMP-30, which can accelerate the curing reaction, increase the degree of cross-linking, enhance the mechanical properties, and improve the epoxy resin bonding ability.

[0020] DMP-30 can effectively increase the curing speed and degree of curing, allowing the adhesive to meet mechanical property requirements more quickly. At the same time, its hydroxyl groups can interact with epoxy resins, improving the adhesive's bonding ability and ensuring the firmness of the bonding interface.

[0021] Furthermore, the defoaming agent is XY-692, which can eliminate bubbles generated when stirring and mixing SW-70 and E51, improve mixing uniformity, reduce curing defects, and ensure the integrity of mechanical properties.

[0022] During the preparation of the adhesive, XY-692 can effectively remove bubbles generated during the stirring process, improve the uniformity of the mixed coating, and reduce internal defects of the material caused by the presence of bubbles, thereby improving the mechanical properties and durability of the adhesive after curing.

[0023] In a second aspect, the present application provides a method for preparing the low-temperature epoxy resin adhesive as described in the first aspect, the steps comprising:

[0024] Mixing raw materials including the silica and the reinforcing fiber to obtain the first filler in powder form;

[0025] The SW-70 and the E51 are stirred and mixed to obtain a mixed resin;

[0026] Mixing the first filler and the mixed resin, adding the defoamer, heating and stirring, to obtain the component A;

[0027] mixing raw materials including the silicon dioxide to obtain a second filler;

[0028] The diamine curing agent and the second filler are stirred and mixed, the curing accelerator is added, and the mixture is heated and stirred to obtain the B component.

[0029] This preparation step helps reduce the risk of filler agglomeration and ensures uniform dispersion. Adding silica in two parts to components A and B helps reduce the viscosity of either single component, ensures that the silica content reaches the expected level, and promotes uniform mixing of high-filler systems.

[0030] Furthermore, the heating and stirring requirements are: heating to 70° C. and stirring at a speed of 50 rpm for 2 hours.

[0031] Controlling temperature and time facilitates uniform mixing and avoids local overheating or insufficient reaction. At the same time, controlling the rotation speed prevents shear damage in high-filler systems, such as avoiding breakage of reinforcing fibers.

[0032] In a third aspect, the present application provides a method for using the epoxy resin adhesive for low temperature as described in the first aspect, wherein the component A and the component B are stirred and mixed in a mass ratio of 1.5 to 1.7:1, and the temperature is raised to 40°C to 50°C while stirring, and the mixture is cured at room temperature for 7 to 8 days after construction.

[0033] Construction at 40℃~50℃ can reduce the mixed viscosity, improve fluidity and extend the application period. After curing at room temperature for 7~8 days, full cross-linking ensures the final strength.

[0034] The beneficial effects of the present invention are as follows: the epoxy resin adhesive for low temperature of the present invention has high hardness and strength after curing, can bear high weight, and the epoxy resin still has high modulus and strength at low temperature, and also has strong impact resistance; the adhesive can be stably cured at room temperature or even lower temperature, has good bonding performance at low temperature, has a moderate curing rate and a moderate construction time, and solves the problem of short construction time; the adhesive has thixotropic properties and can be used in places where flowable adhesives cannot be used. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 1 is a diagram showing the compression test results of the adhesives prepared in various embodiments at room temperature after curing.

[0036] Figure 2 Graphs showing compression test results at -50°C for the adhesives prepared in various embodiments after curing.

[0037] Figure 3 Graphs showing compression test results at -110°C for the adhesives prepared in various embodiments after curing.

[0038] Figure 4 1 is a graph showing the shear test results of the adhesives prepared in various embodiments at room temperature after curing. DETAILED DESCRIPTION

[0039] To make the purpose, technical solutions, and advantages of the embodiments of the present disclosure more clear, the technical solutions of the embodiments of the present disclosure are clearly and completely described below. Obviously, the described embodiments are part of the embodiments of the present disclosure, not all of the embodiments. Based on the described embodiments of the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0040] It should be understood that, under the premise of no conflict, any and all embodiments of the present invention can be combined with the technical features in any other embodiment or multiple other embodiments to obtain additional embodiments. The present invention includes such combinations to obtain additional embodiments.

[0041] In this specification, groups and substituents thereof can be selected by those skilled in the art to provide stable structural moieties and compounds. When substituents are described by conventional chemical formulas written from left to right, the substituents also include chemically equivalent substituents obtained when the structural formula is written from right to left.

[0042] Unless otherwise specified, all technical and scientific terms used herein have the standard meanings in the art to which the claimed subject matter belongs. If there are multiple definitions for a term, the definition herein shall prevail.

[0043] The embodiment of the present application provides an epoxy resin adhesive for low temperature, comprising component A and component B, wherein the working ratio of component A to component B is 1.7-1.5:1 by mass;

[0044] Component A includes SW-70 10wt%~30wt%, E51 10wt%~20wt%, defoamer 0.1wt%~1wt%, and the balance is the first filler;

[0045] Component B includes 20wt%~40wt% of diamine curing agent, 0.1wt%~1wt% of curing accelerator, and the balance is the second filler;

[0046] The first filler contains reinforcing fibers, and both the first filler and the second filler contain silicon dioxide.

[0047] SW-70 (a tetraglycidylamine-based epoxy resin) has a high epoxy value and forms a highly crosslinked structure when cured with a diamine curing agent. The IPN effect created by its combination with E51 (a bisphenol A-based epoxy resin) further enhances the degree of crosslinking, significantly improving the hardness and strength of the adhesive. The components synergistically enhance the adhesive's strength. A ratio of 1.5 to 1.7:1 between components A and B ensures sufficient reaction between the epoxy resin and curing agent, resulting in a more complete crosslinking network and optimized mechanical properties.

[0048] In the examples of the present application, the epoxy resin is a composition of SW-70 and E51, with the corresponding mass ratio being (1-4):2. The curing agent is a diamine curing agent DDM.

[0049] The inventors discovered that the SW-70 in this application has a high epoxy value and, when cured with the diamine curing agent DDM, produces a highly cross-linked epoxy resin, achieving higher hardness and strength. Furthermore, the rigid structure of benzene rings in SW-70 and DDM effectively enhances the strength of the epoxy resin. The E51 epoxy resin, on the other hand, exhibits excellent adhesive properties and can form an IPN effect with SW-70, further promoting the cross-linking of the epoxy resin, resulting in improved strength and hardness of the resulting epoxy resin adhesive.

[0050] Specifically, the complete components of the adhesive include:

[0051] Component A: SW-70 10-30%, E51 10-20%, bacterial cellulose 1-20%, defoamer 0.1-1%, 1250 mesh silica balance.

[0052] Component B: DDM 20-40%, 1250 mesh silica 40-60%, heavy calcium 10-30%, accelerator 0.1-1%.

[0053] The adhesive of the present invention has good bonding properties even at low temperatures, can be stably cured at room temperature or even lower temperatures, has a moderate curing rate and a moderate construction time, which solves the problem of short construction time. It has thixotropic properties and can be used in places where flowable adhesives cannot be used. After curing, it has high hardness and strength and can withstand high weight. The epoxy resin still has a high modulus and strength at low temperatures, and also has strong impact resistance; it has strong corrosion resistance and its performance does not change after long-term storage.

[0054] The adhesive of the present invention does not contain heavy metal salts, is safe, environmentally friendly, non-toxic and odorless, the treatment liquid does not contain toxic substances such as nickel, cobalt or other heavy metals, and the wastewater is non-toxic and harmless. It can be widely used in the fields of construction, furniture, home appliances, etc.

[0055] The micron-sized silica in the first and second fillers effectively improves the hardness, compressive strength, and impact resistance of the cured adhesive. Furthermore, the addition of a large amount of silica imparts excellent thixotropy to the adhesive, enabling its application in applications where flowable adhesives are unsuitable.

[0056] In this application, bacterial cellulose, silicon dioxide, and heavy calcium are selected as fillers. Preferably, in component A, the mass ratio of silicon dioxide to bacterial cellulose is (4-5.5):2, while in component B, the mass ratio of silicon dioxide to heavy calcium is (4-5):1.

[0057] When the mass ratio of silica to bacterial cellulose is between 4 and 5.5:2, it can ensure the strength enhancement effect of silica while fully exerting the toughening effect of bacterial cellulose, avoiding performance degradation due to too much or too little of one component.

[0058] The inventor has found that adding a large amount of micron-sized silicon dioxide in the present application can effectively improve the hardness, compressive strength and the impact resistance of the epoxy resin after curing, and adding a large amount of silicon dioxide can effectively improve the thixotropic performance of the epoxy resin, so that it can be used in the place where flowable epoxy resin cannot be used. And adding a certain amount of bacterial cellulose can build a three-dimensional network in the epoxy matrix, through physical cross-linking and dispersing load, suppress matrix yielding and microcrack to produce and make better shearing performance and compression modulus in the material. And adding a certain amount of heavy calcium that the particle size is finer can effectively fill the space between the micron-sized silicon dioxide, make the epoxy resin after curing more dense, make it have higher compressive strength and compression modulus, and the interface performance between heavy calcium and the epoxy resin is better simultaneously, can ensure that heavy calcium has good dispersibility in the epoxy resin.

[0059] In this application, a curing accelerator and a defoamer are selected as auxiliary agents. Preferably, the accelerator is DMP-30, and the defoamer is preferably XY-692.

[0060] The inventors discovered that adding DMP-30 can effectively increase the curing speed and degree of cure, thereby improving its mechanical properties. Furthermore, the hydroxyl group in DMP-30 effectively enhances the bonding ability of epoxy resins. Adding XY-692 can remove bubbles generated during stirring, improve the uniformity of the mixed coating, and reduce bubbles, thereby improving the mechanical properties after curing.

[0061] The present application also provides a method for preparing the above-mentioned low-temperature epoxy resin adhesive, comprising the following steps:

[0062] Component A:

[0063] (1) Premix silica and bacterial cellulose using a blender and stir for 1 h to obtain powder A (the first filler).

[0064] (2) SW-70 and E51 were premixed with a stirring paddle and stirred for 1 h to obtain resin A (mixed resin).

[0065] (3) Mix powder A and resin A in a certain proportion (satisfying the dosage relationship of component A), add defoaming agent, raise the temperature to 70°C, and stir at a stirring speed of 50 rpm for 2 hours.

[0066] (4) After mixing evenly, take out the sample for later use.

[0067] Component B:

[0068] (1) Premix silica and heavy calcium using a blender and stir for 1 hour to obtain powder B (second filler).

[0069] (2) Then, DDM and powder B were mixed in a certain proportion, and accelerator was added. The temperature was raised to 70°C and stirred at a stirring speed of 50 rpm for 2 h.

[0070] (3) After mixing evenly, take out the sample for later use.

[0071] This method premixes the filler and resin, ensuring full contact between fillers like silica and bacterial cellulose and the resin. Heating at 70°C and stirring at 50 rpm for two hours reduces the resin's viscosity, promoting uniform mixing of the components and ensuring uniform dispersion of the filler within the resin, preventing agglomeration. The heating and stirring process helps the defoamer fully function, removing bubbles and stabilizing the adhesive's performance.

[0072] The present application also provides a method for using the above-mentioned low-temperature epoxy resin adhesive, which includes the following steps:

[0073] (1) Take samples of components A and B in a mass ratio of 1.5 to 1.7:1, stir with a stirring paddle, and raise the temperature to 40°C to 50°C while stirring until evenly mixed.

[0074] Curing time (25℃):

[0075] (1) Curing begins after 30h~36h;

[0076] (2) Hardness reaches 30 after 72h;

[0077] (3) Completely cured in 7-8 days.

[0078] Example 1

[0079] Example 1 provides a two-component epoxy adhesive, which includes the following components, calculated by mass percentage: A: SW-70 (Hunan Saierwei New Materials Technology Co., Ltd.) 15%, E51 (Zhengzhou Penghui Chemical Products Co., Ltd.) 15%, 1250 mesh silica 60%, bacterial cellulose 9%, defoamer (XY-692, Wuhan Lanabai Pharmaceutical Chemical Co., Ltd.) 1%; B: DDM 40%, 1250 mesh silica 49.9%, heavy calcium 10%, accelerator (DMP-30, Shandong Jinruida New Materials Co., Ltd.) 0.1%.

[0080] The mass mixing ratio of the two-component epoxy adhesive is A:B=1.7:1.

[0081] On the other hand, this embodiment also provides a method for preparing a two-component epoxy adhesive (for low-temperature epoxy resin adhesive), comprising the following steps:

[0082] Component A:

[0083] (1) Premix silica and bacterial cellulose in a blender and stir for 1 h to obtain powder A.

[0084] (2) Premix SW-70 and E51 with a stirring paddle and stir for 1 h to obtain resin A.

[0085] (3) Mix powder A and resin A in a certain proportion, add defoaming agent, raise the temperature to 70°C, and stir at 50 rpm for 2 hours.

[0086] (4) After mixing evenly, take out the sample for later use.

[0087] Component B:

[0088] (1) Premix silica and heavy calcium using a blender and stir for 1 hour to obtain powder B.

[0089] (2) Then, DDM and powder B were mixed in a certain proportion, and accelerator was added. The temperature was raised to 70°C and the stirring speed was 50 rpm for 2 h.

[0090] This embodiment also provides a method for using a two-component epoxy resin, comprising the following steps:

[0091] Take samples of components A and B in a certain proportion, stir with a stirring paddle, raise the temperature to 40-50℃ while stirring, and stir evenly.

[0092] Example 2

[0093] Example 2 provides a two-component epoxy adhesive, which includes the following components, calculated by mass percentage: A: SW-70 (Hunan Saierwei New Materials Technology Co., Ltd.) 20%, E51 (Zhengzhou Penghui Chemical Products Co., Ltd.) 10%, 1250 mesh silica 60%, bacterial cellulose 9%, defoamer (XY-692, Wuhan Lanabai Pharmaceutical Chemical Co., Ltd.) 1%; B: DDM 40%, 1250 mesh silica 49.9%, heavy calcium 10%, accelerator (DMP-30, Shandong Jinruida New Materials Co., Ltd.) 0.1%.

[0094] The mass mixing ratio of the two-component epoxy adhesive is A:B=1.6:1.

[0095] The preparation method is the same as that of Example 1.

[0096] The method of use is the same as that of Example 1.

[0097] Example 3

[0098] Example 3 provides a two-component epoxy adhesive, which includes the following components, calculated by mass percentage: A: SW-70 (Hunan Saierwei New Materials Technology Co., Ltd.) 20%, E51 (Zhengzhou Penghui Chemical Products Co., Ltd.) 10%, 1250 mesh silica 60%, bacterial cellulose 9%, defoamer (XY-692, Wuhan Lanabai Pharmaceutical Chemical Co., Ltd.) 1%; B: DDM 40%, 1250 mesh silica 39.9%, heavy calcium 20%, accelerator (DMP-30, Shandong Jinruida New Materials Co., Ltd.) 0.1%.

[0099] The mass mixing ratio of the two-component epoxy adhesive is A:B=1.6:1.

[0100] The preparation method is the same as that of Example 1.

[0101] The method of use is the same as that of Example 1.

[0102] Example 4

[0103] Example 4 provides a two-component epoxy adhesive, which includes the following components, calculated by mass percentage: A: SW-70 (Hunan Saierwei New Materials Technology Co., Ltd.) 20%, E51 (Zhengzhou Penghui Chemical Products Co., Ltd.) 10%, 1250 mesh silica 60%, bacterial cellulose 9%, defoamer (XY-692, Wuhan Lanabai Pharmaceutical Chemical Co., Ltd.) 1%; B: DDM 40%, 1250 mesh silica 49%, heavy calcium 10%, accelerator (DMP-30, Shandong Jinruida New Materials Co., Ltd.) 1%.

[0104] The mass mixing ratio of the two-component epoxy adhesive is A:B=1.6:1.

[0105] The preparation method is the same as that of Example 1.

[0106] The method of use is the same as that of Example 1.

[0107] Example 5

[0108] Example 5 provides a two-component epoxy adhesive, which includes the following components, calculated by mass percentage: A: SW-70 (Hunan Saierwei New Materials Technology Co., Ltd.) 20%, E51 (Zhengzhou Penghui Chemical Products Co., Ltd.) 10%, 1250 mesh silica 50%, bacterial cellulose 19%, defoamer (XY-692, Wuhan Lanabai Pharmaceutical Chemical Co., Ltd.) 1%; B: DDM 40%, 1250 mesh silica 49.9%, heavy calcium 10%, accelerator (DMP-30, Shandong Jinruida New Materials Co., Ltd.) 0.1%.

[0109] The mass mixing ratio of the two-component epoxy adhesive is A:B=1.6:1.

[0110] The preparation method is the same as that of Example 1.

[0111] The method of use is the same as that of Example 1.

[0112] Example 6

[0113] Example 6 provides a two-component epoxy adhesive, which includes the following components, calculated by mass percentage: A: SW-70 (Hunan Sailvi New Materials Technology Co., Ltd.) 15%, E51 (Zhengzhou Penghui Chemical Products Co., Ltd.) 15%, 1250 mesh silica 50%, bacterial cellulose 19%, defoamer (XY-692, Wuhan Lanabai Pharmaceutical Chemical Co., Ltd.) 1%; B: DDM 40%, 1250 mesh silica 49.9%, heavy calcium 10%, accelerator (DMP-30, Shandong Jinruida New Materials Co., Ltd.) 0.1%.

[0114] The mass mixing ratio of the two-component epoxy adhesive is A:B=1.7:1.

[0115] The preparation method is the same as that of Example 1.

[0116] The method of use is the same as that of Example 1.

[0117] Example 7

[0118] Example 7 provides a two-component epoxy adhesive, which includes the following components, calculated by mass percentage: A: SW-70 (Hunan Saierwei New Materials Technology Co., Ltd.) 10%, E51 (Zhengzhou Penghui Chemical Products Co., Ltd.) 20%, 1250 mesh silica 50%, bacterial cellulose 19%, defoamer (XY-692, Wuhan Lanabai Pharmaceutical Chemical Co., Ltd.) 1%; B: DDM 40%, 1250 mesh silica 49.9%, heavy calcium 10%, accelerator (DMP-30, Shandong Jinruida New Materials Co., Ltd.) 0.1%.

[0119] The mass mixing ratio of the two-component epoxy adhesive is A:B=1.5:1.

[0120] The preparation method is the same as that of Example 1.

[0121] The method of use is the same as that of Example 1.

[0122] Comparative Example 1

[0123] Comparative Example 1 provides a two-component epoxy adhesive, which includes the following components, calculated by mass percentage: A: AG-80 (Guangzhou Yihuisheng Chemical Co., Ltd.) 10%, E51 (Zhengzhou Penghui Chemical Products Co., Ltd.) 20%, 1250 mesh silica 50%, bacterial cellulose 19%, defoamer (XY-692, Wuhan Lanabai Pharmaceutical Chemical Co., Ltd.) 1%; B: DDM 40%, 1250 mesh silica 49.9%, heavy calcium 10%, accelerator (DMP-30, Shandong Jinruida New Materials Co., Ltd.) 0.1%.

[0124] The mass mixing ratio of the two-component epoxy adhesive is A:B=1.5:1.

[0125] Except that SW-70 in step (2) of preparing component A is replaced by AG-80 (another tetraglycidylamine type epoxy resin), the remaining steps are the same as those in Example 1.

[0126] The method of use is the same as that of Example 1.

[0127] Comparative Example 2

[0128] Comparative Example 2 provides a two-component epoxy adhesive, which includes the following components, calculated by mass percentage: A: SW-70 (Hunan Saierwei New Materials Technology Co., Ltd.) 10%, E44 (Zhengzhou Penghui Chemical Products Co., Ltd.) 20%, 1250 mesh silica 50%, bacterial cellulose 19%, defoamer (XY-692, Wuhan Lanabai Pharmaceutical Chemical Co., Ltd.) 1%; B: DDM 40%, 1250 mesh silica 49.9%, heavy calcium 10%, accelerator (DMP-30, Shandong Jinruida New Materials Co., Ltd.) 0.1%.

[0129] The mass mixing ratio of the two-component epoxy adhesive is A:B=1.5:1.

[0130] Except that E51 in step (2) of preparing component A was replaced by E44 (another bisphenol A type epoxy resin), the remaining steps were the same as those in Example 1.

[0131] The method of use is the same as that of Example 1.

[0132] Comparative Example 3

[0133] Comparative Example 3 provides a two-component epoxy adhesive, which includes the following components, calculated by mass percentage: A: E51 (Zhengzhou Penghui Chemical Products Co., Ltd.) 30%, 1250 mesh silica 50%, bacterial cellulose 19%, defoamer (XY-692, Wuhan Lanabai Pharmaceutical Chemical Co., Ltd.) 1%; B: DDM 40%, 1250 mesh silica 59.9%, accelerator (DMP-30, Shandong Jinruida New Materials Co., Ltd.) 0.1%.

[0134] The mass mixing ratio of the two-component epoxy adhesive is A:B=1.5:1.

[0135] Except that SW-70 is not added in step (2) of preparing component A and heavy calcium is not added in step (1) of preparing component B, the remaining steps are the same as those in Example 1.

[0136] The method of use is the same as that of Example 1.

[0137] Comparative Example 4

[0138] Comparative Example 4 provides a two-component epoxy adhesive, which includes the following components, calculated by mass percentage: A: SW-70 (Hunan Saierwei New Materials Technology Co., Ltd.) 10%, E51 (Zhengzhou Penghui Chemical Products Co., Ltd.) 20%, 1250 mesh silica 69%, defoamer (XY-692, Wuhan Lanabai Pharmaceutical Chemical Co., Ltd.) 1%; B: DDM 40%, 1250 mesh silica 49.9%, heavy calcium 10%, accelerator (DMP-30, Shandong Jinruida New Materials Co., Ltd.) 0.1%.

[0139] The mass mixing ratio of the two-component epoxy adhesive is A:B=1.5:1.

[0140] Except that bacterial cellulose was not added in step (1) of preparing component A, the remaining steps were the same as those in Example 1.

[0141] The method of use is the same as that of Example 1.

[0142] Comparative Example 5

[0143] Comparative Example 5 provides a two-component epoxy adhesive, which includes the following components, calculated by mass percentage: A: SW-70 (Hunan Saierwei New Materials Technology Co., Ltd.) 10%, E51 (Zhengzhou Penghui Chemical Products Co., Ltd.) 20%, 1250 mesh silica 50%, bacterial cellulose 19%, defoamer (XY-692, Wuhan Lanabai Pharmaceutical Chemical Co., Ltd.) 1%; B: DDM 40%, 1250 mesh silica 49.9%, heavy calcium 10%, accelerator (DMP-30, Shandong Jinruida New Materials Co., Ltd.) 0.1%.

[0144] The mass mixing ratio of the two-component epoxy adhesive is A:B=3:1.

[0145] The preparation method is the same as that of Example 1.

[0146] The method of use is the same as in Example 1 (of course, the mixing ratio is different).

[0147] The mechanical properties of the epoxy resin adhesives after curing in various examples and comparative examples were measured.

[0148] 1. Compression test

[0149] The two-component epoxy resins prepared in each Example and Comparative Example were weighed and cured according to the specified mixing ratios. Testing was performed after curing at room temperature for 7 days or at 60°C for 8 hours. Compression testing was performed according to ASTM D695. The mixed epoxy resins were cured in a 50 mm x 12.7 mm x 12.7 mm rectangular mold to measure elastic modulus and compressive strength. The prepared epoxy resins were placed in a universal testing machine and compression properties were tested at different temperatures (20°C, -50°C, and -110°C).

[0150] 2. Tensile shear performance test

[0151] The two-component epoxy resins prepared in each example and comparative example were weighed and cured according to the specified mixing ratio. Testing was performed after curing at room temperature for 7 days or at 60°C for 8 hours. The tensile shear test method conforms to ASTM D1002. The mixed epoxy resin was applied to an area approximately 25.4 mm x 12.5 mm on the top of a stainless steel sheet, covered with another sheet of stainless steel, and then cured. The prepared epoxy resins were placed in a universal testing machine and subjected to tensile and shear performance tests at different temperatures (20°C, -50°C, and -110°C).

[0152] The test results are shown in Table 1. Figures 1 to 4 .

[0153] Table 1

[0154]

[0155] in, Figure 1 is the result of compression testing at room temperature, Figure 2 This is the compression test result at -50℃. Figure 3 This is the test result at -110℃.

[0156] It can be seen that the shear strength of Example 7 is the strongest among all the examples and comparative examples, and although the elastic modulus and compressive strength are not the strongest, they are the most balanced; compared with Example 6 and Example 5, it can be found that adding more SW-70 to Example 7 will increase the crosslinking density of the material, making the material itself more brittle, and the shear strength, compressive strength and elastic modulus will decrease. Comparing Example 5 with the examples, it can be seen that if the amount of component B and component A does not match, the performance will be reduced. This is because the reaction is incomplete and the crosslinking density is low. Comparing Example 4 with Example 1, it can be seen that adding a certain amount of bacterial cellulose can effectively improve the compressive strength and compressive modulus of the material. This is because bacterial cellulose can help form a three-dimensional network structure, which can effectively prevent crack propagation and improve the mechanical properties of the epoxy resin.

[0157] Throughout this specification, reference to terms such as "one embodiment," "certain embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that a specific feature, structure, material, or characteristic described in conjunction with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, illustrative uses of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0158] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. An epoxy resin adhesive for low temperature, characterized in that: Comprising component A and component B, wherein the working ratio of component A to component B is 1.5-1.7:1 by mass; The component A includes SW-70 10wt%~30wt%, E51 10wt%~20wt%, defoamer 0.1wt%~1wt%, and the balance is the first filler; The B component includes 20 wt% to 40 wt% of a diamine curing agent, 0.1 wt% to 1 wt% of a curing accelerator, and the balance is a second filler; The first filler contains reinforcing fibers, and both the first filler and the second filler contain silicon dioxide; The reinforcing fiber is bacterial cellulose; in the first filler, the mass ratio of the silicon dioxide to the bacterial cellulose is 4-5.5:2; The second filler further contains heavy calcium, the particle size of the heavy calcium is smaller than that of the silicon dioxide; in the second filler, the mass ratio of the silicon dioxide to the heavy calcium is 4 to 5:1; The silicon dioxide in the first filler is 1250 mesh silicon dioxide; the silicon dioxide in the second filler is 1250 mesh silicon dioxide.

2. The epoxy resin adhesive for low temperature according to claim 1, characterized in that In the component A, the mass ratio of SW-70 to E51 is 1-4:2; and the diamine curing agent is 4'4-diaminodiphenylmethane.

3. The epoxy resin adhesive for low temperature use according to claim 1, characterized in that: The curing accelerator is DMP-30.

4. The epoxy resin adhesive for low temperature use according to claim 1, characterized in that: The defoaming agent is XY-692.

5. The method for preparing the low-temperature epoxy resin adhesive according to any one of claims 1 to 4, characterized in that the steps include: Mixing raw materials including the silica and the reinforcing fiber to obtain the first filler in powder form; The SW-70 and the E51 are stirred and mixed to obtain a mixed resin; Mixing the first filler and the mixed resin, adding the defoamer, heating and stirring, to obtain the component A; mixing raw materials including the silicon dioxide to obtain a second filler; The diamine curing agent and the second filler are stirred and mixed, the curing accelerator is added, and the mixture is heated and stirred to obtain the B component.

6. The preparation method according to claim 5, characterized in that The requirements for the heating and stirring are: heating to 70° C. and stirring at a speed of 50 rpm for 2 h.

7. The method for using the low-temperature epoxy resin adhesive according to any one of claims 1 to 4, characterized in that: The component A and the component B are stirred and mixed in a mass ratio of 1.5-1.7:1, and the temperature is raised to 40°C-50°C while stirring. After construction, the mixture is cured at room temperature for 7 to 8 days.

Images