A low-temperature, moisture-curing two-component epoxy resin composite adhesive and its preparation method and application

Abstract

The present invention discloses a low-temperature, humid-curing two-component epoxy resin composite adhesive, its preparation method, and application. The composite adhesive comprises component A and component B. Component A comprises 33% to 40% epoxy resin, 2% to 6% diluent, 55% to 64% inorganic filler, and 1% to 2% white carbon black. Component B comprises 9% to 14% amine curing agent, 18% to 25% modified amine curing agent, 2% to 5% auxiliary agent, 60% to 70% inorganic filler, 1.0% to 1.5% white carbon black, and 1.0% to 2.0% titanium dioxide. The modified curing agent is a mixture of a cardanol aldehyde amine curing agent, a phenol formaldehyde amine curing agent, and a fatty amine modified amine curing agent. The composite adhesive of the present invention can achieve effective curing in a low-temperature, humid environment and is a novel stone bonding adhesive with excellent performance. It can reduce the processing difficulty of stone composite panels, has high processing efficiency, low processing cost, high use value, and good application prospects.

Description

Technical Field

[0001] The invention relates to a moisture-curing two-component epoxy resin composite adhesive and a preparation method and application thereof. Background Art

[0002] With the continuous improvement of the economy and living standards, natural stone has gained widespread recognition and popularity as a decorative material. However, natural stone is a non-renewable resource, making its rational utilization essential. Due to the aforementioned reasons and the need to reduce production costs in actual production processes, natural stone is typically cut into sheets of appropriate thickness and then bonded together, or bonded to other materials to create composite panels. Both methods require adhesives. Furthermore, stone typically has a moisture content exceeding 0.12%. This is particularly true in some special circumstances, such as rainy days or underwater operations, where the moisture content can reach significantly higher than 0.12%. This makes it difficult to achieve effective bonding between stone and other materials with existing stone composite adhesives. In particular, these commercially available stone composite adhesives struggle to cure at temperatures below 20°C (particularly below 5°C), or require extended curing times. This makes the production of stone composite panels difficult, expensive, and inefficient. Therefore, obtaining an epoxy resin composite adhesive that can cure quickly in low temperature and humidity is of great significance for promoting the widespread use of natural stone. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide a low-temperature and humid-curing two-component epoxy resin composite adhesive and a preparation method and application thereof.

[0004] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0005] A low-temperature, moisture-curing two-component epoxy resin composite adhesive comprising component A and component B;

[0006] The component A comprises the following raw material components in terms of weight percentage:

[0007]

[0008] The component B comprises the following raw materials in percentage by weight:

[0009]

[0010]

[0011] The modified amine curing agent is a mixture of a cashew phenol aldehyde amine curing agent, a phenol formaldehyde amine curing agent, and a fatty amine modified amine curing agent.

[0012] The above-mentioned two-component epoxy resin composite adhesive is further improved, wherein the mass ratio of the cashew phenol aldehyde amine curing agent, the phenol formaldehyde amine curing agent, and the fatty amine modified amine curing agent is 11:4:5.

[0013] The above-mentioned two-component epoxy resin composite adhesive is further improved, and the cardanol aldehyde amine curing agent is prepared by the following method: adding cardanol to the reactor, heating to 45°C to 50°C, adding pentamethylenediamine dropwise, and adding it over 3.0 hours to 3.5 hours, heating to 75°C to 85°C, adding paraformaldehyde in 4 times, and adding it over 2.0 hours to 2.5 hours, heating to 91°C to 95°C and continuing the reaction for 1.5 hours, cooling to 50°C, distilling water and free phenol under vacuum conditions, after 1.5 hours, the temperature reaches 110°C and the distillate no longer appears, stopping heating and distillation, filtering, and obtaining the cardanol aldehyde amine curing agent; the mass ratio of the cardanol, pentamethylenediamine, and paraformaldehyde is 302:107:115.

[0014] The above-mentioned two-component epoxy resin composite adhesive is further improved, and the phenol formaldehyde amine curing agent is prepared by the following method: adding phenol to a reactor, heating to 35°C to 40°C, adding pentamethylenediamine dropwise, and adding it over 2.0 hours to 3.0 hours, heating to 70°C to 75°C, adding paraformaldehyde in four portions, and adding it over 2.0 hours to 2.5 hours, heating to 91°C to 95°C, continuing to react for 1.5 hours, cooling to 50°C, distilling water and free phenol under vacuum conditions, and after 1.5 hours, the temperature reaches 110°C and no fraction appears, stopping heating and distillation, and filtering to obtain the phenol formaldehyde amine curing agent; the mass ratio of the phenol, pentamethylenediamine, and paraformaldehyde is 94:107:115.

[0015] The above-mentioned two-component epoxy resin composite adhesive is further improved, and the fatty amine-modified amine curing agent is prepared by the following method: adding pentamethylenediamine and triethylenetetramine to a reactor, adjusting the temperature to 31°C to 34°C, adding E-51 epoxy resin benzyl alcohol solution dropwise, and adding it over 3.5 hours to 4.0 hours, raising the temperature to 35°C to 40°C, continuing the reaction for 3 hours, filtering, and obtaining the fatty amine-modified amine curing agent; the mass ratio of the pentamethylenediamine, triethylenetetramine, and E-51 epoxy resin benzyl alcohol solution is 109:73:107; the E-51 epoxy resin benzyl alcohol solution is obtained by mixing E-51 epoxy resin and benzyl alcohol; and the mass ratio of the E-51 epoxy resin to benzyl alcohol is 3:7.

[0016] The above-mentioned two-component epoxy resin composite adhesive is further improved, wherein the epoxy resin is bisphenol A epoxy resin, diluted bisphenol A epoxy resin or a mixture thereof; when the epoxy resin is a mixture of bisphenol A epoxy resin and diluted bisphenol A epoxy resin, the mass ratio of the bisphenol A epoxy resin to the diluted bisphenol A epoxy resin is 7:13.

[0017] The above-mentioned two-component epoxy resin composite adhesive is further improved, wherein the diluted bisphenol A epoxy resin is a mixture prepared by mixing bisphenol A epoxy resin and phenyl glycidyl ether; the viscosity of the diluted bisphenol A epoxy resin is 800mPa·s / 25℃~1500mPa·s / 25℃, and the epoxy equivalent is 148g / mol~155g / mol.

[0018] The above-mentioned two-component epoxy resin composite adhesive is further improved, wherein in the component A: the diluent is at least one of phenyl glycidyl ether, benzyl alcohol, polyether 3050, and dibutyl phthalate.

[0019] The above two-component epoxy resin composite adhesive is further improved, wherein in the component A: the inorganic filler is activated calcium carbonate; the mesh size of the activated calcium carbonate is 600 mesh to 2000 mesh.

[0020] The above two-component epoxy resin composite adhesive is further improved, wherein in the component A: the white carbon black is at least one of fumed white carbon black and precipitated white carbon black.

[0021] The above-mentioned two-component epoxy resin composite adhesive is further improved, wherein in the B component: the amine curing agent is an amine-modified curing agent 593; and the auxiliary agent is at least one of benzyl alcohol, isobutyl alcohol, and dibutyl phthalate.

[0022] The above two-component epoxy resin composite adhesive is further improved, wherein in the B component: the inorganic filler is activated calcium carbonate; the mesh size of the activated calcium carbonate is 600 mesh to 2000 mesh.

[0023] The above two-component epoxy resin composite adhesive is further improved, wherein in the B component: the silica is at least one of fumed silica and precipitated silica.

[0024] The above two-component epoxy resin composite adhesive is further improved in that the weight ratio of component A to component B is 1.95-2.05:1.

[0025] As a general technical concept, the present invention also provides a method for preparing the above-mentioned low-temperature moisture-curing two-component epoxy resin composite adhesive, which is further improved and includes the following steps:

[0026] S1. Heat the epoxy resin to 70°C to 80°C, add a diluent, mix well, add white carbon black and calcium carbonate in sequence, and stir to obtain component A; in a reactor, add an amine curing agent, a modified amine curing agent, and an auxiliary agent step by step, mix well, add white carbon black, titanium dioxide, and calcium carbonate step by step, and stir to obtain component B;

[0027] S2. Component A and component B are mixed to obtain a two-component epoxy resin adhesive with high strength, low viscosity, and low-temperature and moisture-curing properties.

[0028] As a general technical concept, the present invention also provides a use of the above-mentioned low-temperature moisture-curing two-component epoxy resin composite adhesive or the low-temperature moisture-curing two-component epoxy resin composite adhesive prepared by the above-mentioned preparation method in the preparation of stone composite panels.

[0029] In the present invention, when the low-temperature moisture-curing two-component epoxy resin composite adhesive is used to prepare the stone composite board, the low-temperature moisture-curing two-component epoxy resin composite adhesive is coated between stones or between stones and other reinforcing materials.

[0030] Compared with the prior art, the advantages of the present invention are:

[0031] In view of the defects of existing stone composite adhesives such as difficulty in curing under low temperature and humid conditions, and the resulting shortcomings such as great difficulty in processing, low production efficiency, and high cost, the present invention provides a two-component epoxy resin composite adhesive that cures under low temperature and humid conditions, comprising component A and component B. In component B, the modified curing agent used is a mixture of a cashew phenol aldehyde amine curing agent, a phenol formaldehyde amine curing agent, and a fatty amine modified amine curing agent. The cashew phenol aldehyde amine curing agent and the phenol formaldehyde amine curing agent contain phenolic hydroxyl groups, which can give the curing agent moisture and low-temperature curing properties, so that the composite adhesive of the present invention has excellent curing properties under low temperature and humid conditions and can be quickly cured. At the same time, the added fatty amine modified amine curing agent overcomes the defect of poor toughness when using the cashew phenol aldehyde amine curing agent and the phenol formaldehyde amine curing agent, can improve the toughness of the composite adhesive, and thus can exhibit more excellent performance. Therefore, by using the cashew phenol aldehyde amine curing agent, the phenol formaldehyde amine curing agent, and the fatty amine modified amine curing agent, the composite adhesive of the present invention can not only be quickly cured under low temperature and humid conditions, but also has good toughness. On this basis, the present invention further optimizes the ratio of powder (inorganic filler, white carbon black) to glue (epoxy resin, diluent, curing agent, additives) to ensure that neither component A nor component B is stratified. This also prevents stratification of the composite glue of the present invention and improves the brushing performance of the composite glue, which helps to reduce the difficulty of brushing and is more convenient to use. At the same time, it can also increase the bonding strength of the composite glue and reduce costs. In addition, white carbon black can prevent sagging, and titanium dioxide can increase leveling and improve whiteness. By optimizing the amount of white carbon black and titanium dioxide, the composite glue is also made colorless and transparent, which helps to avoid the color of the composite glue itself from adversely affecting the quality of the stone. The two-component epoxy resin composite adhesive of the present invention has the advantages of high bonding strength, no delamination, good brushing performance, easy use, low shrinkage, and the ability to achieve effective curing in low-temperature and humid environments. It is a new type of epoxy resin adhesive with excellent performance and can be widely used for effective bonding between stones and between stones and other materials. It can effectively overcome the adverse effects of the stone itself and environmental factors on curing, and can reduce the processing difficulty of stone composite panels. It has high processing efficiency, low processing cost, high use value, and good application prospects. DETAILED DESCRIPTION

[0032] The present invention will be further described below in conjunction with specific preferred embodiments, but the scope of protection of the present invention is not limited thereby.

[0033] The raw materials and instruments used in the following examples are all commercially available; the equipment and preparation processes used are all conventional equipment and conventional processes unless otherwise specified.

[0034] Example 1

[0035] A low-temperature, moisture-curing two-component epoxy resin composite adhesive comprises component A and component B, wherein component A comprises the following raw material components in percentage by weight:

[0036]

[0037] The component B comprises the following raw materials in percentage by weight:

[0038]

[0039]

[0040] In this embodiment, the modified amine curing agent is a mixture of cashew phenol aldehyde amine curing agent, phenol formaldehyde amine curing agent, and fatty amine modified amine curing agent, wherein the mass ratio of cashew phenol aldehyde amine curing agent, phenol formaldehyde amine curing agent, and fatty amine modified amine curing agent is 11:4:5.

[0041] In this embodiment, the cardanol aldehyde amine curing agent was prepared by the following method: 302g of cardanol was weighed and added to a 1000mL four-necked flask, heated to 45-50°C, 107g of pentamethylenediamine was added dropwise for 3.5 hours, heated to 75-85°C, 115g of paraformaldehyde was added in 4 times, and the addition was completed within 2.5 hours. The temperature was raised to 91-95°C and the reaction was continued for 1.5 hours, then cooled to 50°C, vacuum was opened (below -0.090MPa), water and free phenol were distilled, and after 1.5 hours, the temperature reached 110°C and the distillate no longer appeared, and the heating and distillation were stopped. The curing agent was obtained by filtering the flask.

[0042] In the present embodiment, the phenol formaldehyde amine curing agent was prepared by the following method: 94 g of phenol was weighed and added to a 1000 mL four-necked flask, heated to 35-40 ° C, 107 g of pentamethylenediamine was added dropwise for 3.0 hours, the temperature was raised to 70-75 ° C, 115 g of paraformaldehyde was added in 4 portions, and the addition was completed over 2.5 hours. The temperature was raised to 91-95 ° C and the reaction was continued for 1.5 hours, then the temperature was lowered to 50 ° C, vacuum was opened (below -0.090 MPa), water and free phenol were distilled, and after 1.0 hour, the temperature reached 110 ° C and the distillation was stopped and the curing agent was filtered.

[0043] In this embodiment, a fatty amine-modified amine curing agent was prepared by the following method: 109 g of pentamethylenediamine and 73 g of triethylenetetramine were weighed and added to a 1000 mL four-necked flask, respectively. The temperature was adjusted to 31-34° C., 107 g of E-51 epoxy resin benzyl alcohol solution (in this solution, the mass ratio of E-51 epoxy resin to benzyl alcohol was 3:7) was added dropwise for 4.0 hours, the temperature was raised to 35-40° C., and the reaction was continued for 3 hours. The contents of the flask were filtered to obtain the curing agent.

[0044] In this embodiment, the epoxy resin is a mixture of bisphenol A epoxy resin and diluted bisphenol A epoxy resin, wherein the mass ratio of bisphenol A epoxy resin to diluted bisphenol A epoxy resin is 7:13. The diluted bisphenol A epoxy resin is a mixture prepared by mixing bisphenol A epoxy resin and phenyl glycidyl ether. The viscosity of phenyl glycidyl ether is 6 mPa·s / 25°C, the viscosity of the diluted bisphenol A epoxy resin is 950 mPa·s / 25°C, and the epoxy equivalent is 152 g / mol.

[0045] In this embodiment, in component A, the diluent used is a mixture of phenyl glycidyl ether, benzyl alcohol, polyether 3050, and dibutyl phthalate, and their mass ratio is 5:8:5:2.

[0046] In this embodiment, in component A, the calcium carbonate used is a mixture of 600 mesh, 1000 mesh, 1500 mesh, and 2000 mesh activated calcium carbonate, and their mass ratio is 10:5:3:2.

[0047] In this embodiment, in component A, the silica used is a mixture of fumed silica and precipitated silica, and the mass ratio of the two is 1:1.

[0048] In this embodiment, in component B, the amine curing agent used is amine-modified curing agent 593 (commercially available).

[0049] In this embodiment, in component B, the auxiliary agent used is a mixture of benzyl alcohol, isobutyl alcohol, and dibutyl phthalate, and their mass ratio is 9:4:7.

[0050] In this embodiment, in component B, the calcium carbonate used is a mixture of 600 mesh, 1000 mesh, 1500 mesh, and 2000 mesh activated calcium carbonate, and their mass ratio is 6:7:5:2.

[0051] In this embodiment, in component B, the silica used is a mixture of fumed silica and precipitated silica, and the mass ratio of the two is 1:1.

[0052] In this embodiment, in component B, the titanium dioxide used is ordinary titanium dioxide.

[0053] In this embodiment, the weight ratio of component A to component B is 2:1.

[0054] A method for preparing the low-temperature, moisture-curing two-component epoxy resin composite adhesive of the present embodiment comprises the following steps:

[0055] Heat 34.0 g of epoxy resin to 75-80° C. and add it into a mixing container. Add 2.0 g of diluent and mix well. Add 1.0 g of white carbon black and 63.0 g of calcium carbonate stepwise and disperse them evenly using a high-speed disperser to prepare component A.

[0056] 9.0 g of amine curing agent, 18.0 g of modified amine curing agent and 2.0 g of auxiliary agent were added to the mixing container in sequence and mixed evenly. 1.0 g of white carbon black, 1.0 g of titanium dioxide and 69.0 g of calcium carbonate were added step by step and dispersed evenly using a high-speed disperser to prepare component B.

[0057] Mix component A and component B in a weight ratio of 2:1 and mix them evenly to obtain a low-temperature and moisture-curing two-component epoxy resin composite adhesive that can be used directly.

[0058] An application of the low-temperature, moisture-curing two-component epoxy resin composite adhesive in the above embodiment in preparing a stone composite board is specifically to apply the low-temperature, moisture-curing two-component epoxy resin composite adhesive between two pieces of stone to make a stone composite board.

[0059] The properties of the low-temperature, humid-curing two-component epoxy resin composite adhesive of this example are shown in Table 1. Additionally, the stone composite panels prepared in this example were cured at temperatures of 5°C, 20°C, and 25°C, with the results shown in Table 1. These results demonstrate that the two-component epoxy resin composite adhesive of the present invention can effectively cure in a low-temperature, humid environment, exhibiting high bond strength, no delamination, excellent coating properties, ease of use, and low shrinkage. Its post-curing performance meets the requirements for stone composite adhesives, demonstrating its superior performance as a novel epoxy resin adhesive. Furthermore, the cured stone composite panels meet the production requirements.

[0060] Example 2

[0061] A low-temperature, moisture-curing two-component epoxy resin composite adhesive comprises component A and component B, wherein component A comprises the following raw material components in percentage by weight:

[0062]

[0063] Component B includes the following raw materials in percentage by weight:

[0064]

[0065] In this embodiment, the modified amine curing agent is a mixture of cashew phenol aldehyde amine curing agent, phenol formaldehyde amine curing agent, and fatty amine modified amine curing agent, wherein the mass ratio of cashew phenol aldehyde amine curing agent, phenol formaldehyde amine curing agent, and fatty amine modified amine curing agent is 11:4:5.

[0066] In this embodiment, the cardanol aldehyde amine curing agent was prepared by the following method: 302g of cardanol was weighed and added to a 1000mL four-necked flask, heated to 45-50°C, 107g of pentamethylenediamine was added dropwise for 3.5 hours, heated to 75-85°C, 115g of paraformaldehyde was added in 4 times, and the addition was completed within 2.5 hours. The temperature was raised to 91-95°C and the reaction was continued for 1.5 hours, then cooled to 50°C, vacuum was opened (below -0.090MPa), water and free phenol were distilled, and after 1.5 hours, the temperature reached 110°C and the distillate no longer appeared, and the heating and distillation were stopped. The curing agent was obtained by filtering the flask.

[0067] In the present embodiment, the phenol formaldehyde amine curing agent was prepared by the following method: 94 g of phenol was weighed and added to a 1000 mL four-necked flask, heated to 35-40 ° C, 107 g of pentamethylenediamine was added dropwise for 3.0 hours, the temperature was raised to 70-75 ° C, 115 g of paraformaldehyde was added in 4 portions, and the addition was completed over 2.5 hours. The temperature was raised to 91-95 ° C and the reaction was continued for 1.5 hours, then the temperature was lowered to 50 ° C, vacuum was opened (below -0.090 MPa), water and free phenol were distilled, and after 1.0 hour, the temperature reached 110 ° C and the distillation was stopped and the curing agent was filtered.

[0068] In this embodiment, a fatty amine-modified amine curing agent was prepared by the following method: 109 g of pentamethylenediamine and 73 g of triethylenetetramine were weighed and added to a 1000 mL four-necked flask, respectively. The temperature was adjusted to 31-34° C., 107 g of E-51 epoxy resin benzyl alcohol solution (in this solution, the mass ratio of E-51 epoxy resin to benzyl alcohol was 3:7) was added dropwise for 4.0 hours, the temperature was raised to 35-40° C., and the reaction was continued for 3 hours. The contents of the flask were filtered to obtain the curing agent.

[0069] In this embodiment, the epoxy resin is a mixture of bisphenol A epoxy resin and diluted bisphenol A epoxy resin, wherein the mass ratio of bisphenol A epoxy resin to diluted bisphenol A epoxy resin is 7:13. The diluted bisphenol A epoxy resin is a mixture prepared by mixing bisphenol A epoxy resin and phenyl glycidyl ether. The viscosity of phenyl glycidyl ether is 6 mPa·s / 25°C, the viscosity of the diluted bisphenol A epoxy resin is 950 mPa·s / 25°C, and the epoxy equivalent is 152 g / mol.

[0070] In this embodiment, in component A, the diluent used is a mixture of phenyl glycidyl ether, benzyl alcohol, polyether 3050, and dibutyl phthalate, and their mass ratio is 5:8:5:2.

[0071] In this embodiment, in component A, the calcium carbonate used is a mixture of 600 mesh, 1000 mesh, 1500 mesh, and 2000 mesh activated calcium carbonate, and their mass ratio is 10:5:3:2.

[0072] In this embodiment, in component A, the silica used is a mixture of fumed silica and precipitated silica, and the mass ratio of the two is 1:1.

[0073] In this embodiment, in component B, the amine curing agent used is amine-modified curing agent 593 (commercially available).

[0074] In this embodiment, in component B, the auxiliary agent used is a mixture of benzyl alcohol, isobutyl alcohol, and dibutyl phthalate, and their mass ratio is 11:4:5.

[0075] In this embodiment, in component B, the calcium carbonate used is a mixture of 600 mesh, 1000 mesh, 1500 mesh, and 2000 mesh activated calcium carbonate, and their mass ratio is 6:7:5:2.

[0076] In this embodiment, in component B, the silica used is a mixture of fumed silica and precipitated silica, and the mass ratio of the two is 1:1.

[0077] In this embodiment, in component B, the titanium dioxide used is ordinary titanium dioxide.

[0078] In this embodiment, the weight ratio of component A to component B is 2:1.

[0079] A method for preparing the low-temperature, moisture-curing two-component epoxy resin composite adhesive of the present embodiment comprises the following steps:

[0080] Heat 39.0 g of epoxy resin to 75-80° C. and add it into a mixing container. Add 4.2 g of diluent and mix well. Add 1.8 g of white carbon black and 55.0 g of calcium carbonate stepwise and disperse them evenly using a high-speed disperser to prepare component A.

[0081] 12.5 g of amine curing agent, 21.5 g of modified amine curing agent and 3.0 g of auxiliary agent were added to the mixing container in sequence and mixed evenly. 1.1 g of white carbon black, 1.4 g of titanium dioxide and 60.5 g of calcium carbonate were added step by step and dispersed evenly using a high-speed disperser to prepare component B.

[0082] Mix component A and component B in a weight ratio of 2:1 and mix them evenly to obtain a low-temperature and moisture-curing two-component epoxy resin composite adhesive that can be used directly.

[0083] An application of the low-temperature, moisture-curing two-component epoxy resin composite adhesive in the above embodiment in preparing a stone composite board is specifically to apply the low-temperature, moisture-curing two-component epoxy resin composite adhesive between two pieces of stone to make a stone composite board.

[0084] The properties of the low-temperature, humid-curing two-component epoxy resin composite adhesive of this example are shown in Table 1. Additionally, the stone composite panels prepared in this example were cured at temperatures of 5°C, 20°C, and 25°C, with the results shown in Table 1. These results demonstrate that the two-component epoxy resin composite adhesive of the present invention can effectively cure in a low-temperature, humid environment, exhibiting high bond strength, no delamination, excellent coating properties, ease of use, and low shrinkage. Its post-curing performance meets the requirements for stone composite adhesives, demonstrating its superior performance as a novel epoxy resin adhesive. Furthermore, the cured stone composite panels meet the production requirements.

[0085] Example 3

[0086] A low-temperature, moisture-curing two-component epoxy resin composite adhesive comprises component A and component B, wherein component A comprises the following raw material components in percentage by weight:

[0087]

[0088]

[0089] Component B includes the following raw materials in percentage by weight:

[0090]

[0091] In this embodiment, the modified amine curing agent is a mixture of cashew phenol aldehyde amine curing agent, phenol formaldehyde amine curing agent, and fatty amine modified amine curing agent, wherein the mass ratio of cashew phenol aldehyde amine curing agent, phenol formaldehyde amine curing agent, and fatty amine modified amine curing agent is 11:4:5.

[0092] In this embodiment, the cardanol aldehyde amine curing agent was prepared by the following method: 302g of cardanol was weighed and added to a 1000mL four-necked flask, heated to 45-50°C, 107g of pentamethylenediamine was added dropwise for 3.5 hours, heated to 75-85°C, 115g of paraformaldehyde was added in 4 times, and the addition was completed within 2.5 hours. The temperature was raised to 91-95°C and the reaction was continued for 1.5 hours, then cooled to 50°C, vacuum was opened (below -0.090MPa), water and free phenol were distilled, and after 1.5 hours, the temperature reached 110°C and the distillate no longer appeared, and the heating and distillation were stopped. The curing agent was obtained by filtering the flask.

[0093] In the present embodiment, the phenol formaldehyde amine curing agent was prepared by the following method: 94 g of phenol was weighed and added to a 1000 mL four-necked flask, heated to 35-40 ° C, 107 g of pentamethylenediamine was added dropwise for 3.0 hours, the temperature was raised to 70-75 ° C, 115 g of paraformaldehyde was added in 4 portions, and the addition was completed over 2.5 hours. The temperature was raised to 91-95 ° C and the reaction was continued for 1.5 hours, then the temperature was lowered to 50 ° C, vacuum was opened (below -0.090 MPa), water and free phenol were distilled, and after 1.0 hour, the temperature reached 110 ° C and the distillation was stopped and the curing agent was filtered.

[0094] In this embodiment, a fatty amine-modified amine curing agent was prepared by the following method: 109 g of pentamethylenediamine and 73 g of triethylenetetramine were weighed and added to a 1000 mL four-necked flask, respectively. The temperature was adjusted to 31-34° C., 107 g of E-51 epoxy resin benzyl alcohol solution (in this solution, the mass ratio of E-51 epoxy resin to benzyl alcohol was 3:7) was added dropwise for 4.0 hours, the temperature was raised to 35-40° C., and the reaction was continued for 3 hours. The contents of the flask were filtered to obtain the curing agent.

[0095] In this example, the epoxy resin is a mixture of bisphenol A epoxy resin and diluted bisphenol A epoxy resin, wherein the mass ratio of bisphenol A epoxy resin to diluted bisphenol A epoxy resin is 7:13. The diluted bisphenol A epoxy resin is a mixture of bisphenol A epoxy resin and phenyl glycidyl ether. The viscosity of phenyl glycidyl ether is 6 mPa·s / 25°C, the viscosity of the diluted bisphenol A epoxy resin is 950 mPa·s / 25°C, and the epoxy equivalent weight is 152 g / mol.

[0096] In this embodiment, in component A, the diluent used is a mixture of phenyl glycidyl ether, benzyl alcohol, polyether 3050, and dibutyl phthalate, and their mass ratio is 5:8:5:2.

[0097] In this embodiment, in component A, the calcium carbonate used is a mixture of 600 mesh, 1000 mesh, 1500 mesh, and 2000 mesh activated calcium carbonate, and their mass ratio is 10:5:3:2.

[0098] In this embodiment, in component A, the silica used is a mixture of fumed silica and precipitated silica, and the mass ratio of the two is 1:1.

[0099] In this embodiment, in component B, the amine curing agent used is amine-modified curing agent 593 (commercially available).

[0100] In this embodiment, in component B, the auxiliary agent used is a mixture of benzyl alcohol, isobutyl alcohol, and dibutyl phthalate, and their mass ratio is 11:4:5.

[0101] In this embodiment, in component B, the calcium carbonate used is a mixture of 600 mesh, 1000 mesh, 1500 mesh, and 2000 mesh activated calcium carbonate, and their mass ratio is 6:7:5:2.

[0102] In this embodiment, in component B, the silica used is a mixture of fumed silica and precipitated silica, and the mass ratio of the two is 1:1.

[0103] In this embodiment, in component B, the titanium dioxide used is ordinary titanium dioxide.

[0104] In this embodiment, the weight ratio of component A to component B is 2:1.

[0105] A method for preparing the low-temperature, moisture-curing two-component epoxy resin composite adhesive of the present embodiment comprises the following steps:

[0106] Heat 36.0 g of epoxy resin to 75-80°C and add it into a mixing container. Add 3.5 g of diluent and mix well. Add 1.5 g of white carbon black and 59.0 g of calcium carbonate step by step and disperse them evenly using a high-speed disperser to prepare component A.

[0107] 12.5 g of amine curing agent, 19.5 g of modified amine curing agent and 2.5 g of auxiliary agent were added to the mixing container in sequence and mixed evenly. 1.2 g of white carbon black, 1.3 g of titanium dioxide and 63.0 g of calcium carbonate were added step by step and dispersed evenly using a high-speed disperser to prepare component B.

[0108] Mix component A and component B in a weight ratio of 2:1 and mix them evenly to obtain a low-temperature and moisture-curing two-component epoxy resin composite adhesive that can be used directly.

[0109] An application of the low-temperature, moisture-curing two-component epoxy resin composite adhesive in the above embodiment in preparing a stone composite board is specifically to apply the low-temperature, moisture-curing two-component epoxy resin composite adhesive between two pieces of stone to make a stone composite board.

[0110] The properties of the low-temperature, humid-curing two-component epoxy resin composite adhesive of this example are shown in Table 1. Additionally, the stone composite panels prepared in this example were cured at temperatures of 5°C, 20°C, and 25°C, with the results shown in Table 1. These results demonstrate that the two-component epoxy resin composite adhesive of the present invention can effectively cure in a low-temperature, humid environment, exhibiting high bond strength, no delamination, excellent coating properties, ease of use, and low shrinkage. Its post-curing performance meets the requirements for stone composite adhesives, demonstrating its superior performance as a novel epoxy resin adhesive. Furthermore, the cured stone composite panels meet the production requirements.

[0111] Comparative Example 1

[0112] A two-component epoxy resin composite adhesive is substantially the same as Example 3, except that: in the two-component epoxy resin composite adhesive of Comparative Example 1, component B includes the following raw material components in terms of weight percentage:

[0113] Amine curing agent 12.5%,

[0114]

[0115] The two-component epoxy resin composite adhesive of Comparative Example 1 was coated between two pieces of stone to produce a stone composite board.

[0116] The properties of the two-component epoxy resin composite adhesive in Comparative Example 1 are shown in Table 1. Furthermore, the stone composite panels prepared in Comparative Example 1 were cured at temperatures of 5°C, 20°C, and 25°C, with the results shown in Table 1. These results indicate that the two-component epoxy resin composite adhesive in Comparative Example 1 delaminated when used as an adhesive for bonding stone, exhibiting significant degradation in low-temperature curing performance and strength, failing to meet requirements.

[0117] Comparative Example 2

[0118] A two-component epoxy resin composite adhesive is substantially the same as Example 3, except that: in the two-component epoxy resin composite adhesive of Comparative Example 2, component B includes the following raw material components in terms of weight percentage:

[0119] Amine curing agent 2%,

[0120]

[0121] The two-component epoxy resin composite adhesive of Comparative Example 2 was coated between two pieces of stone to produce a stone composite board.

[0122] The properties of the two-component epoxy resin composite adhesive in Comparative Example 2 are shown in Table 1. Furthermore, the stone composite panels produced in Comparative Example 2 were cured at temperatures of 5°C, 20°C, and 25°C, with the results shown in Table 1. These results indicate that the two-component epoxy resin composite adhesive in Comparative Example 1, when used as an adhesive for bonding stone, exhibits the following adverse effects: slow curing rate, delamination, and significant strength loss, failing to meet requirements.

[0123] Table 1 Performance comparison of different two-component epoxy resin composite adhesives and stone composite panels

[0124]

[0125]

[0126] The above embodiments are merely preferred embodiments of the present invention, and the scope of protection of the present invention is not limited to the above embodiments. All technical solutions that fall within the scope of protection of the present invention are within the scope of protection of the present invention. It should be noted that improvements and modifications that can be made by a person skilled in the art without departing from the principles of the present invention are also considered to be within the scope of protection of the present invention.

Claims

1. A low-temperature, moisture-curing two-component epoxy resin composite adhesive, characterized in that: The invention comprises component A and component B; the weight ratio of component A to component B is 1.95-2.05:1; The component A comprises the following raw material components in terms of weight percentage: The sum of the weight percentages of the raw materials is 100%; The component B comprises the following raw materials in percentage by weight: The sum of the weight percentages of the raw materials is 100%; The modified amine curing agent is a mixture of a phenol aldehyde amine curing agent, a phenol formaldehyde amine curing agent, and a fatty amine modified amine curing agent; the mass ratio of the phenol aldehyde amine curing agent, the phenol formaldehyde amine curing agent, and the fatty amine modified amine curing agent is 11:4:5; The cardanol aldehyde amine curing agent is prepared by the following method: adding cardanol to a reactor, heating to 45° C. to 50° C., adding pentamethylenediamine dropwise over 3.0 to 3.5 hours, heating to 75° C. to 85° C., adding paraformaldehyde in four portions over 2.0 to 2.5 hours, heating to 91° C. to 95° C., continuing the reaction for 1.5 hours, cooling to 50° C., distilling water and free phenol under vacuum conditions, and after 1.5 hours, the temperature reaches 110° C. and no fraction appears, stopping heating and distillation, and filtering to obtain the cardanol aldehyde amine curing agent; The phenol formaldehyde amine curing agent is prepared by the following method: adding phenol to a reactor, heating to 35° C. to 40° C., adding pentamethylenediamine dropwise over 2.0 to 3.0 hours, heating to 70° C. to 75° C., adding paraformaldehyde in four portions over 2.0 to 2.5 hours, heating to 91° C. to 95° C., continuing the reaction for 1.5 hours, cooling to 50° C., distilling water and free phenol under vacuum conditions, and after 1.5 hours, when the temperature reaches 110° C. and no more distillate appears, stopping heating and distillation, and filtering to obtain the phenol formaldehyde amine curing agent; The fatty amine modified amine curing agent is prepared by the following method: adding pentamethylenediamine and triethylenetetramine into a reactor, adjusting the temperature to 31° C. to 34° C., adding E-51 epoxy resin benzyl alcohol solution dropwise over 3.5 to 4.0 hours, raising the temperature to 35° C. to 40° C., continuing the reaction for 3 hours, and filtering to obtain the fatty amine modified amine curing agent.

2. The two-component epoxy resin composite adhesive according to claim 1, characterized in that: In the preparation method of the cardanol aldehyde amine curing agent, the mass ratio of the cardanol, pentamethylenediamine and paraformaldehyde is 302:107:115; In the preparation method of the phenol formaldehyde amine curing agent, the mass ratio of the phenol, pentamethylenediamine and paraformaldehyde is 94:107:115; In the preparation method of the fatty amine-modified amine curing agent, the mass ratio of pentamethylenediamine, triethylenetetramine, and E-51 epoxy resin benzyl alcohol solution is 109:73:107; the E-51 epoxy resin benzyl alcohol solution is obtained by mixing E-51 epoxy resin and benzyl alcohol; and the mass ratio of E-51 epoxy resin to benzyl alcohol is 3:

7.

3. The two-component epoxy resin composite adhesive according to claim 1 or 2, characterized in that: The epoxy resin is bisphenol A epoxy resin, diluted bisphenol A epoxy resin or a mixture thereof; when the epoxy resin is a mixture of bisphenol A epoxy resin and diluted bisphenol A epoxy resin, the mass ratio of the bisphenol A epoxy resin to the diluted bisphenol A epoxy resin is 7:

13.

4. The two-component epoxy resin composite adhesive according to claim 3, characterized in that: The diluted bisphenol A epoxy resin is a mixture prepared by mixing bisphenol A epoxy resin and phenyl glycidyl ether; the viscosity of the diluted bisphenol A epoxy resin is 800mPa·s / 25°C to 1500mPa·s / 25°C, and the epoxy equivalent is 148g / mol to 155g / mol.

5. The two-component epoxy resin composite adhesive according to claim 1 or 2, characterized in that: In the component A, the diluent is at least one of phenyl glycidyl ether, benzyl alcohol, polyether 3050, and dibutyl phthalate; the inorganic filler is activated calcium carbonate; the mesh size of the activated calcium carbonate is 600 to 2000 mesh; and the white carbon black is at least one of fumed white carbon black and precipitated white carbon black.

6. The two-component epoxy resin composite adhesive according to claim 1 or 2, characterized in that: In the B component: the amine curing agent is an amine-modified curing agent 593; the auxiliary agent is at least one of benzyl alcohol, isobutyl alcohol, and dibutyl phthalate; the inorganic filler is activated calcium carbonate; the mesh size of the activated calcium carbonate is 600 mesh to 2000 mesh; the white carbon black is at least one of fumed white carbon black and precipitated white carbon black.

7. A method for preparing a low-temperature, moisture-curing two-component epoxy resin composite adhesive according to any one of claims 1 to 6, characterized in that: The following steps are involved: S1. Heat the epoxy resin to 70°C to 80°C, add a diluent, mix well, add white carbon black and calcium carbonate in sequence, and stir to obtain component A; in a reactor, add an amine curing agent, a modified amine curing agent, and an auxiliary agent step by step, mix well, add white carbon black, titanium dioxide, and calcium carbonate step by step, and stir to obtain component B; S2. Component A and component B are mixed to obtain a two-component epoxy resin adhesive with high strength, low viscosity, and low-temperature and moisture-curing properties.

8. Use of the low-temperature, moisture-curing two-component epoxy resin composite adhesive according to any one of claims 1 to 6 or the low-temperature, moisture-curing two-component epoxy resin composite adhesive prepared by the preparation method according to claim 7 in preparing stone composite panels.

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