High-strength glue for pull-out test of aerogel wall thermal insulation material

Abstract

The invention discloses high-strength glue for a pull-out test of an aerogel wall thermal insulation material. The high-strength glue comprises the following raw materials in parts by weight: 30-50 parts of epoxy resin, 0.5-2 parts of a silane coupling agent, 1-5 parts of modified carbon fibers, 8-15 parts of a curing agent, 5-12 parts of a diluent and 2-10 parts of a toughening modifier. By adopting the reactive diluent, on one hand, the overall viscosity of the high-strength glue can be reduced, and on the other hand, the reactive diluent contains epoxy groups or other active groups, can participate in curing reaction and becomes a part of a cross-linked network; by adding the toughening modifier, the toughness of the prepared high-strength glue can be improved, so that the brittleness of the epoxy resin glue is improved, the cured epoxy resin glue is not easy to crack, and the interface stability between the epoxy resin glue and the aerogel wall thermal insulation material is improved. The modified carbon fiber is added into the high-strength glue, so that the cohesion of the high-strength glue can be improved, and the cohesion of the high-strength glue can be improved.

Description

Technical Field

[0001] This invention belongs to the field of adhesive materials technology, specifically, it relates to a high-strength adhesive for pull-out tests of aerogel wall insulation materials. Background Technology

[0002] In the construction industry, pull-out testing of wall insulation materials is a crucial step in the acceptance process to assess the bond strength between the insulation material and the wall. Traditional insulation materials typically achieve good adhesion using conventional adhesives during pull-out tests. However, aerogel wall insulation materials possess unique microstructure and surface characteristics, making it difficult for traditional adhesives to form a strong bond. This is because aerogel materials contain numerous nanoscale pores and have low surface energy, preventing traditional adhesives from effectively penetrating and wetting them. This results in insufficient interfacial strength, making it easy for the adhesive layer to detach from the insulation material during pull-out tests. Consequently, it becomes impossible to accurately measure the actual bonding performance of aerogel wall insulation materials, impacting the assessment of project quality.

[0003] To address the aforementioned issues, this invention provides an adhesive that can enhance the bonding strength of aerogel insulation materials, ensuring the proper conduct of pull-out tests on wall insulation materials. The invention offers the following technical solution. Summary of the Invention

[0004] The purpose of this invention is to provide a manufacturing process for anti-fouling protective gloves, which solves the problem in the prior art that the adhesion between the adhesive and the aerogel insulation material is poor, and the adhesive layer is prone to detach from the insulation material during the pull-out test, affecting the normal conduct of the pull-out test.

[0005] The objective of this invention can be achieved through the following technical solutions: A high-strength adhesive for pull-out testing of aerogel wall insulation materials comprises the following components in parts by weight: 30-50 parts epoxy resin, 0.5-2 parts silane coupling agent, 1-5 parts modified carbon fiber, 8-15 parts curing agent, 5-12 parts diluent, and 2-10 parts toughening modifier.

[0006] The diluent is an active diluent, specifically, such as 1,4-butanediol diglycidyl ether or neopentyl glycol diglycidyl ether; Using reactive diluents can reduce the overall viscosity of high-strength adhesives. On the other hand, reactive diluents themselves contain epoxy groups or other active groups, which can participate in the curing reaction and become part of the cross-linking network. The toughening modifier is a core-shell rubber particle or a liquid rubber toughening agent such as carboxyl-terminated butadiene-acrylonitrile rubber, hydroxyl-terminated polybutadiene rubber, or polysulfide rubber. Adding toughening modifiers can improve the toughness of the prepared high-strength adhesive, thereby reducing the brittleness of the epoxy resin adhesive, making the cured epoxy resin adhesive less prone to cracking, and improving the interfacial stability between the epoxy resin adhesive and the aerogel wall insulation material.

[0007] The high-strength adhesive is prepared as follows: Mix the components evenly according to the weight ratio to obtain a high-strength adhesive; The viscosity of the high-strength adhesive at 25 degrees Celsius is 500-700 mPas. The viscosity can be adjusted by changing the type of epoxy resin, the amount of modified nano-silica, diluent, etc. By adjusting the viscosity of the high-strength adhesive, it is possible to make the high-strength adhesive have good fluidity, making it easier for the high-strength adhesive to flow into the micro-nano pores of the aerogel wall insulation layer, thereby improving the bonding performance between the high-strength adhesive and the aerogel wall insulation layer support. The method for preparing the modified carbon fiber is as follows: First, the carbon fiber is cleaned and dried, and then the dried carbon fiber is oxidized. Carbon fibers with silane coupling agents grafted onto their surface are obtained by treating oxidized carbon fibers with silane coupling agents. Specifically: Prepare an anhydrous ethanol solution of silane coupling agent; immerse the oxidized carbon fiber in the anhydrous ethanol solution of silane coupling agent, and then reflux the reaction under stirring conditions. After the reaction is completed, separate the solid and liquid to obtain carbon fiber, and wash the carbon fiber with anhydrous ethanol 2 to 3 times, and then dry it to obtain carbon fiber with silane coupling agent grafted on the surface. Nano-silica is obtained by surface treatment with silane coupling agent to obtain nano-silica with silane coupling agent grafted on the surface. Specifically: Prepare an anhydrous ethanol suspension of nano-silica (using anhydrous ethanol as a medium, add nano-silica to it and then ultrasonically stir); add a silane coupling agent to the suspension, and after the silane coupling agent dissolves, reflux the mixture under stirring conditions. After the reaction is complete, separate the solid and liquid phases; wash the solid product with anhydrous ethanol, and then dry it to obtain nano-silica with silane coupling agent grafted on its surface.

[0008] First, nano-silica with silane coupling agent grafted on its surface is dispersed in anhydrous ethanol and then sonicated to obtain a suspension. Carbon fibers with silane coupling agent grafted on their surface are immersed in the suspension and then subjected to reflux reaction. After the reaction is completed, the mixture is cooled to room temperature, washed with anhydrous ethanol, and dried to obtain modified carbon fibers.

[0009] The amount of nano-silica added to the suspension is 5g-15g per 100ml of anhydrous ethanol, and the weight ratio of nano-silica grafted with silane coupling agent to carbon fiber grafted with silane coupling agent is 1:0.05-0.2. Among them, a grafting reaction can occur between the silane coupling agent that performs surface grafting modification on oxidized carbon fibers and the silane coupling agent that performs surface grafting modification on nano-silica. For example, surface grafting modification of oxidized carbon fibers can be performed using silane coupling agent KH-550, and surface grafting modification of nano-silica can be performed using silane coupling agent KH-560.

[0010] By adding modified carbon fibers to high-strength adhesives, the cohesive force of the adhesives can be improved, preventing tearing of the adhesives during pull-out tests and ensuring the accuracy of the results. Furthermore, uniformly attaching nano-silica particles to the surface of the carbon fibers allows for the uniform integration of nano-silica into the epoxy resin matrix. Compared to directly adding nano-silica, this avoids agglomeration. The attached nano-silica particles also increase the surface roughness of the carbon fibers, further enhancing the bonding strength of the carbon fibers in the high-strength adhesive system and contributing to improved cohesive force.

[0011] The beneficial effects of this invention are: 1. Using reactive diluents can reduce the overall viscosity of high-strength adhesives. On the other hand, reactive diluents themselves contain epoxy groups or other active groups, which can participate in the curing reaction and become part of the cross-linking network. 2. By adding toughening modifiers, the toughness of the prepared high-strength adhesive can be improved, thereby reducing the brittleness of the epoxy resin adhesive, making the cured epoxy resin adhesive less prone to cracking, and improving the interfacial stability between the epoxy resin adhesive and the aerogel wall insulation material.

[0012] 3. By adding modified carbon fiber to high-strength adhesive, the cohesive force of the adhesive can be improved, preventing tearing of the adhesive itself during pull-out testing and affecting the accuracy of the pull-out test results. In addition, by uniformly attaching nano-silica particles to the surface of carbon fiber, nano-silica can be uniformly added into the epoxy resin matrix. Compared with directly adding nano-silica, this avoids the agglomeration of nano-silica. Moreover, the attached nano-silica particles can improve the surface roughness of carbon fiber, further improving the bonding strength of carbon fiber in the high-strength adhesive system, which is beneficial to improving the cohesive force of the high-strength adhesive. Detailed Implementation

[0013] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0014] Example 1 A high-strength adhesive for pull-out testing of aerogel wall insulation materials, the raw material weight ratio is as follows: 40 parts epoxy resin (E-51), 1 part silane coupling agent (KH-560), 3 parts modified carbon fiber, 10 parts curing agent (polyetheramine D230), 8 parts diluent (1,4-butanediol diglycidyl ether), and 6 parts toughening modifier (core-shell rubber particles). All components were mechanically stirred and mixed at 25°C for 1 hour, and then degassed under vacuum. The viscosity at 25°C was 580 mPas. Pull-out strength (aerogel substrate): 3.8 MPa (interfacial / cohesive mixed failure) The preparation method of modified carbon fiber is as follows: The carbon fiber was immersed in concentrated nitric acid (65℃, 4h), washed with water until neutral, and dried at 120℃. The oxidized carbon fiber was immersed in a 2wt% KH-550 anhydrous ethanol solution, refluxed at 80℃ for 2 hours, washed with ethanol 3 times, and dried. Nano-SiO2 was dispersed in anhydrous ethanol at a concentration of 10 g / 100 mL, 3 wt% KH-560 was added, refluxed at 80 °C for 2 h, centrifuged, washed, and dried. KH-560 modified SiO2 was dispersed in anhydrous ethanol at a concentration of 10 g / 100 mL. The mixture was sonicated for 30 min, and then KH-550 modified carbon fiber was added at a weight ratio of 1:0.1. The mixture was refluxed at 80 °C for 3 h, and then washed and dried.

[0015] Example 2 A high-strength adhesive for pull-out testing of aerogel wall insulation materials, the raw material weight ratio is as follows: 30 parts epoxy resin (E-44), 0.5 parts silane coupling agent (KH-550), 1 part modified carbon fiber, 8 parts curing agent (methylhexahydrophthalic anhydride), 5 parts diluent (neopentyl glycol diglycidyl ether), and 2 parts toughening modifier (carboxyl-terminated nitrile rubber). All components were stirred and mixed at 25°C for 40 minutes, followed by vacuum degassing. The viscosity at 25°C was 510 mPas. Tensile strength: 3.2 MPa (mainly due to interface failure); The preparation method of modified carbon fiber is as follows: The carbon fiber was immersed in concentrated nitric acid (65℃, 4h), washed with water until neutral, and dried at 120℃. The oxidized carbon fiber was immersed in a 2wt% KH-550 anhydrous ethanol solution, refluxed at 80℃ for 2 hours, washed with ethanol 3 times, and dried. Nano-SiO2 was dispersed in anhydrous ethanol at a concentration of 5 g / 100 mL, 3 wt% KH-560 was added, refluxed at 80 °C for 2 h, centrifuged, washed, and dried. KH-560 modified SiO2 was dispersed in anhydrous ethanol at a concentration of 10 g / 100 mL. The mixture was sonicated for 30 min, and then KH-550 modified carbon fiber was added at a weight ratio of 1:0.05 between SiO2 and carbon fiber. The mixture was refluxed at 80 °C for 3 h, and then washed and dried.

[0016] Example 3 A high-strength adhesive for pull-out testing of aerogel wall insulation materials, the raw material weight ratio is as follows: 50 parts epoxy resin (E-51), 2 parts silane coupling agent (KH-570), 5 parts modified carbon fiber, 15 parts curing agent (imidazolium EMI-24), 12 parts diluent (1,4-butanediol diglycidyl ether), and 10 parts toughening modifier (polysulfide rubber). The preparation method of modified carbon fiber is as follows: The carbon fiber was immersed in concentrated nitric acid (65℃, 4h), washed with water until neutral, and dried at 120℃. The oxidized carbon fiber was immersed in a 2wt% KH-550 anhydrous ethanol solution, refluxed at 80℃ for 2 hours, washed with ethanol 3 times, and dried. Nano-SiO2 was dispersed in anhydrous ethanol at a concentration of 15 g / 100 mL, 3 wt% KH-560 was added, refluxed at 80 °C for 2 h, centrifuged, washed, and dried. KH-560 modified SiO2 was dispersed in anhydrous ethanol at a concentration of 10 g / 100 mL. The mixture was sonicated for 30 min, and then KH-550 modified carbon fiber was added at a weight ratio of 1:0.2 between SiO2 and carbon fiber. The mixture was refluxed at 80 °C for 3 h, and then washed and dried.

[0017] All components were stirred and mixed at 25°C for 1.5 hours, followed by vacuum degassing. The viscosity at 25°C was 650 mPa·s. Pull-out strength: 4.1 MPa (mainly cohesive failure).

[0018] Comparative Example 1 No modified carbon fiber was added, and other conditions were the same as in Example 1.

[0019] Comparative Example 2 Unmodified carbon fibers and nano-silica were added, and other conditions were the same as in Example 1.

[0020] Performance testing and data analysis The viscosity and pull-out strength of the high-strength adhesives prepared under the conditions of Examples 1 to 2 were tested at 25 degrees Celsius. The test results are shown in the table below: Classification Viscosity (mpas) Pull-out strength (MPa) Failure Mode Example 1 580 3.8 Mixed destruction Example 2 510 3.2 Interface destruction is the main focus. Example 3 650 4.1 Cohesion destruction Comparative Example 1 530 1.6 Cohesive tearing of adhesive layer Comparative Example 2 620 2.0 Interface stripping As shown in the table above, the present invention, through the combination of raw materials and the addition of modified carbon fiber, can significantly improve the cohesive force of high-strength adhesive and its bonding ability with the aerogel insulation layer, and significantly improve the pull-out strength of high-strength adhesive after curing.

[0021] The above description is merely an example and illustration of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described or use similar methods to replace them, as long as they do not deviate from the invention or exceed the scope defined in the claims, they should all fall within the protection scope of the present invention.

Claims

1. A high-strength adhesive for pull-out testing of aerogel wall insulation materials, characterized in that, The raw materials consist of the following components in parts by weight: 30-50 parts epoxy resin, 0.5-2 parts silane coupling agent, 1-5 parts modified carbon fiber, 8-15 parts curing agent, 5-12 parts diluent, and 2-10 parts toughening modifier.

2. The method for preparing the modified carbon fiber is as follows: First, the carbon fiber is cleaned and dried, and then the dried carbon fiber is oxidized. Carbon fibers with silane coupling agents grafted onto their surface are obtained by treating oxidized carbon fibers with silane coupling agents. Nano-silica is obtained by surface treatment with silane coupling agent to obtain nano-silica with silane coupling agent grafted on the surface. First, nano-silica with silane coupling agent grafted on its surface is dispersed in anhydrous ethanol and then sonicated to obtain a suspension. Carbon fibers with silane coupling agent grafted on their surface are immersed in the suspension and then subjected to reflux reaction. After the reaction is completed, the mixture is cooled to room temperature, washed with anhydrous ethanol, and dried to obtain modified carbon fibers.

3. The high-strength adhesive for pull-out testing of aerogel wall insulation materials according to claim 1, characterized in that, The viscosity of the high-strength adhesive at 25 degrees Celsius is 500-700 mPas.

4. The high-strength adhesive for pull-out testing of aerogel wall insulation materials according to claim 1, characterized in that, The diluent is an active diluent.

5. The high-strength adhesive for pull-out testing of aerogel wall insulation materials according to claim 3, characterized in that, The diluent is 1,4-butanediol diglycidyl ether or neopentyl glycol diglycidyl ether.

6. The high-strength adhesive for pull-out testing of aerogel wall insulation materials according to claim 1, characterized in that, The toughening modifier is a core-shell rubber particle or a carboxyl-terminated butadiene-acrylonitrile rubber, a hydroxyl-terminated polybutadiene rubber, or a polysulfide rubber.

7. The high-strength adhesive for pull-out testing of aerogel wall insulation materials according to claim 1, characterized in that, A grafting reaction can occur between a silane coupling agent that has been surface-grafted onto oxidized carbon fibers and a silane coupling agent that has been surface-grafted onto nano-silica.

8. The high-strength adhesive for pull-out testing of aerogel wall insulation materials according to claim 1, characterized in that, When preparing modified carbon fibers, the amount of nano-silica added to the suspension is 5g-15g per 100ml of anhydrous ethanol, and the weight ratio of nano-silica with silane coupling agent grafted on the surface to carbon fibers with silane coupling agent grafted on the surface is 1:0.05-0.2.