High-adhesion two-component epoxy ceramic tile adhesive and preparation method thereof

Abstract

The invention relates to the technical field of adhesives, in particular to a high-adhesion bi-component epoxy tile adhesive and a preparation method thereof. The invention relates to a water-based paint, which is composed of a component A and a component B. The component A comprises the following components in percentage by weight: 15-25% of resin, 28-38% of fine filler, 0.1-2% of hydrophilic vapor silicon and the balance of coarse filler; and the component B comprises 15-25% of a curing agent, 25-40% of a fine filler, 0.1-2% of hydrophilic vapor silicon, 0.01-0.1% of toner and the balance of a coarse filler. By adding hydrophilic vapor silicon, the thermal shock performance and the initial adhesion performance of the ceramic tile adhesive can be effectively improved; and when nitrogen is used for adsorbing hydrophilic vapor silicon with the specific surface area of 150-250 m < 2 > / g, the shear bonding strength after thermal shock can still be larger than or equal to 2.0 MPa, meanwhile, the airing time is larger than or equal to 20 min, and the tensile bonding strength can still be larger than or equal to 0.5 MPa.

Description

Technical Field

[0001] This invention relates to the field of adhesive technology, specifically to a high-adhesion two-component epoxy tile adhesive and its preparation method. Background Technology

[0002] With the continuous development of the building decoration industry, the installation quality of ceramic tiles, as a commonly used decorative material, has attracted much attention. Traditional tile adhesives have certain limitations in terms of bonding performance, water resistance, and durability: Traditional tile adhesives are prone to tile detachment during long-term use, which not only affects aesthetics but may also pose safety hazards. This is especially common in humid environments or areas with large temperature fluctuations. Insufficient water resistance is also a major problem with traditional tile adhesives. When tile adhesives are exposed to humid environments for extended periods, their internal structure is easily damaged, leading to reduced bonding strength and affecting the lifespan of the tiles. Regarding durability, traditional tile adhesives are prone to cracking and hollowing when exposed to extreme environments such as thermal shock and freeze-thaw cycles. This significantly diminishes the decorative effect of the tiles and requires frequent repairs and replacements, increasing costs and construction difficulty.

[0003] Chinese invention patent application CN120289136A discloses a high-adhesion, anti-aging tile adhesive and its preparation method. It comprises 10-50 parts epoxy functionalized siloxane resin, 40-60 parts cement, 5-20 parts hardener, 5-10 parts thickener, 1-5 parts antioxidant, and 20-30 parts filler. This tile adhesive exhibits excellent adhesion and anti-aging properties, but its water resistance needs improvement. Summary of the Invention

[0004] The first aspect of this invention provides a high-adhesion two-component epoxy tile adhesive, comprising component A and component B. By weight percentage, component A comprises: 15-25% resin, 28-38% fine filler, 0.1-2% hydrophilic silica, with coarse filler making up the balance; component B comprises: 15-25% curing agent, 25-40% fine filler, 0.1-2% hydrophilic silica, 0.01-0.1% colorant, with coarse filler making up the balance.

[0005] Optionally, by weight percentage, component A comprises: 18-22% resin, 28-35% fine filler, 0.1-1% hydrophilic fumed silica, with coarse filler to make up the balance; component B comprises: 15-20% curing agent, 25-35% fine filler, 0.5-2% hydrophilic fumed silica, 0.01-0.1% colorant, with coarse filler to make up the balance.

[0006] The nitrogen adsorption specific surface area of ​​the hydrophilic silica is 150-250 m². 2 / g.

[0007] Optionally, the nitrogen adsorption specific surface area of ​​the hydrophilic silica is 180-220 m². 2 / g.

[0008] This study found that adding hydrophilic silica can effectively improve the thermal shock resistance and initial tack of tile adhesive. The high specific surface area and surface hydroxyl groups of hydrophilic silica can enhance interfacial compatibility: the surface hydroxyl groups combine with the polar groups (epoxy groups, amine groups) of the resin and curing agent to form a "bridging" structure, thereby improving the cohesion of the system.

[0009] Further research revealed that nitrogen adsorption with a specific surface area of ​​150-250 m² was effective. 2 / g of hydrophilic fumed silica maintains a shear bond strength ≥2.0MPa after thermal shock, and a tensile bond strength ≥0.5MPa after an air-drying time ≥20min. Nanoscale particles fill the gaps between fine and coarse fillers, optimizing system density and reducing stress concentration during thermal shock, thus preventing cracking. Simultaneously, the loose structure of the hydrophilic fumed silica reduces system viscosity, mitigating issues such as a heavy feel and excessive stickiness during application.

[0010] The weight ratio of fine packing to coarse packing in component A is 1:(1.2-2).

[0011] This study found that by limiting the weight ratio of fine filler to coarse filler in component A to 1:(1.2-2), the shear bond strength of tile adhesive can be improved, achieving a shear bond strength ≥3MPa. Fine filler, with its small particle size and large specific surface area, can fill the voids between coarse filler particles, forming a tightly packed structure of "fine filling coarse voids," reducing the internal porosity of the system. This structure enhances the interfacial contact area between the filler and the resin matrix, allowing for more uniform stress distribution and preventing stress concentration fracture caused by localized porosity. Simultaneously, the highly active surface of the fine filler can form stronger chemical bonds with the resin, further strengthening the interfacial bonding force. When the ratio is within this range, it ensures both the skeletal support provided by the coarse filler and the full filling and densification by the fine filler, synergistically improving the overall shear resistance and achieving a shear bond strength ≥3MPa. If the ratio deviates, excessive coarse filler will result in difficulty filling voids and a loose structure; excessive fine filler will lead to excessively strong interparticle interactions, easily inducing internal stress, both of which will result in a decrease in strength.

[0012] Optionally, the weight ratio of fine packing to coarse packing in component A is 1:(1.3-1.8).

[0013] Further research by the applicant revealed that by limiting the weight ratio of fine filler to coarse filler in component B to 1:(1.3-2.5), workability and heat resistance can be further balanced. This balance is likely achieved by regulating the system's rheology and post-curing structural stability. Fine filler can adjust the system viscosity through surface adsorption, imparting suitable thixotropy to component B, ensuring easy application and preventing sagging during construction. Coarse filler, through mechanical support between particles, prevents the system from becoming too viscous due to excessive fine filler, improving the workability. Simultaneously, the mixed structure formed by coarse and fine fillers at this ratio exhibits both density and a certain degree of elasticity after curing. Fine filler ensures a compact structure, reducing the space for gas expansion during thermal shock; a moderate amount of coarse filler provides a certain deformation buffer, alleviating internal stress caused by temperature changes and preventing cracking. If the ratio exceeds this range, excessively fine filler results in excessively high system viscosity, making construction difficult and causing stress concentration during thermal shock; excessively coarse filler leads to a loose structure, resulting in a grainy feel during construction and uneven heat conduction due to voids, compromising overall performance.

[0014] Optionally, the weight ratio of fine packing to coarse packing in component A is 1:(1.4-1.7).

[0015] The weight ratio of fine packing to coarse packing in component B is 1:(1.3-2.5).

[0016] Optionally, the weight ratio of fine packing to coarse packing in component B is 1:(1.2-2.3).

[0017] Optionally, the weight ratio of fine packing to coarse packing in component B is 1:(1.3-2.1).

[0018] The fine filler includes activated calcium, which has an average particle size of 5-20 micrometers.

[0019] This application research found that the fine filler includes activated calcium, with an average particle size of 5-20 micrometers, which can further improve the water resistance of tile adhesive. This is likely because the activated calcium, after surface treatment, possesses higher chemical activity, allowing it to not only bind through physical filling but also form stronger hydrogen bonds and coordination bonds with epoxy groups in the resin and amine groups in the curing agent. This enhances the interfacial bonding between the filler and the matrix, enabling the strong interfacial bond between activated calcium and the matrix to resist water molecule penetration and damage under immersion conditions, thus preventing a decrease in adhesive strength.

[0020] Optionally, the average particle size of the active calcium is 8-12 micrometers.

[0021] The coarse filler includes calcium carbonate, and the average particle size of the calcium carbonate is 50-300 mesh.

[0022] Optionally, the average particle size of the calcium carbonate is 60-120 mesh.

[0023] The resin has an epoxy equivalent of 150-300 g / eq and a viscosity of 100-1500 mPa·s at 25°C.

[0024] Optionally, the epoxy equivalent of the resin is 220-240 g / eq, and the viscosity at 25°C is 200-800 mPa·s.

[0025] The curing agent has an amine value of 200-300 mg KOH / g and a viscosity of 100-1000 mPa·s.

[0026] Optionally, the curing agent has an amine value of 240-260 mg KOH / g and a viscosity of 200-700 mPa·s.

[0027] The weight ratio of component A to component B is 1:(0.8-1.2).

[0028] Optionally, the weight ratio of component A to component B is 1:(0.9-1.1).

[0029] The second aspect of the present invention provides a method for preparing a high-adhesion two-component epoxy tile adhesive, comprising the following steps: mixing the resin and fine filler in component A evenly, adding coarse filler, stirring evenly, adding hydrophilic silica, and stirring evenly under vacuum to obtain component A; mixing the curing agent, fine filler, and color powder in component B evenly, adding coarse filler, stirring evenly, adding hydrophilic silica, and stirring evenly under vacuum to obtain component B.

[0030] Optionally, during the preparation of component A, hydrophilic fumed silica is added in 1-2 separate steps.

[0031] Optionally, during the preparation of component B, the hydrophilic fumed silica is added in two separate steps.

[0032] Beneficial effects

[0033] 1. By adding hydrophilic silica, the thermal shock performance and initial tack of tile adhesive can be effectively improved, while also improving problems such as heavy feel and excessive stickiness during construction.

[0034] 2. Use nitrogen adsorption with a specific surface area of ​​150-250 m². 2 / g of hydrophilic fumed silica still has a shear bond strength of ≥2.0MPa after thermal shock, and a tensile bond strength of ≥0.5MPa after an air-drying time of ≥20min.

[0035] 3. By limiting the weight ratio of fine filler to coarse filler in component A to 1:(1.2-2), the shear bond strength of tile adhesive can be improved, making the shear bond strength of tile adhesive ≥3MPa.

[0036] 4. By limiting the weight ratio of fine filler to coarse filler in component B to 1:(1.3-2.5), the workability (easy to apply) and heat resistance can be further balanced.

[0037] 5. By specifying that the fine filler is activated calcium, and that the average particle size of the activated calcium is 5-20 micrometers, the water resistance of the tile adhesive can be further improved. Detailed Implementation

[0038] Examples 1-2, Comparative Examples 1-6

[0039] A high-adhesion two-component epoxy tile adhesive, composed of component A and component B, is shown in Table 1 by weight percentage, where " / " indicates that the corresponding component was not added. The specific manufacturers, brands, and physical properties of the components are shown in Table 2.

[0040] Table 1

[0041]

[0042]

[0043] Table 2

[0044]

[0045] The high-adhesion two-component epoxy tile adhesives in Examples 1-2 and Comparative Examples 3-6 were prepared as follows: the resin and fine filler in component A were mixed evenly, coarse filler was added, and the mixture was stirred evenly (40 rpm, 10 min). Then, hydrophilic silica was added in two equal portions, and the mixture was stirred evenly (45 rpm, 10 min). The mixture was then stirred under vacuum (45 rpm, 10 min) to obtain component A. The curing agent, fine filler, and colorant were mixed evenly, coarse filler was added, and the mixture was stirred evenly (40 rpm, 10 min). Then, hydrophilic silica was added in two equal portions, and the mixture was stirred evenly (45 rpm, 10 min). The mixture was then stirred under vacuum (45 rpm, 10 min) to obtain component B.

[0046] The two-component epoxy tile adhesive with high adhesion in Comparative Examples 1-2 was prepared as follows: the resin and fine filler were mixed evenly, coarse filler was added, and the mixture was stirred evenly (40 rpm, 10 min), and then stirred under vacuum (45 rpm, 10 min) to obtain component A; the curing agent, fine filler, and color powder were mixed evenly, coarse filler was added, and the mixture was stirred evenly (40 rpm, 10 min), and then stirred under vacuum (45 rpm, 10 min) to obtain component B.

[0047] Performance testing methods

[0048] The two-component epoxy tile adhesives prepared in the examples and comparative examples were subjected to performance tests, and the test data are listed in Table 3.

[0049] The shear bond strength, shear bond strength after immersion in water, shear bond strength after 20 minutes of drying, tensile bond strength, and shear bond strength after thermal shock were all tested in accordance with the following standard: R-type JC / T 547-2017.

[0050] Performance test data

[0051] Table 3

[0052]

[0053] As shown in Table 3, this application, by limiting the composition of components A and B, ensures the construction performance of the tile adhesive while achieving shear bond strength ≥3MPa, shear bond strength after immersion in water ≥2MPa, drying time ≥20min, tensile bond strength ≥2.5MPa, and shear bond strength after thermal shock ≥2MPa. The comparative examples cannot achieve the above effects simultaneously.

Claims

1. A high-adhesion two-component epoxy tile adhesive, characterized in that, Composed of component A and component B, by weight percentage, component A includes: 15-25% resin, 28-38% fine filler, 0.1-2% hydrophilic fumed silica, with coarse filler to make up the balance; component B includes: 15-25% curing agent, 25-40% fine filler, 0.1-2% hydrophilic fumed silica, 0.01-0.1% colorant, with coarse filler to make up the balance.

2. The high-adhesion two-component epoxy tile adhesive according to claim 1, characterized in that, The weight ratio of fine packing to coarse packing in component A is 1:(1.2-2).

3. The high-adhesion two-component epoxy tile adhesive according to claim 1 or 2, characterized in that, The weight ratio of fine packing to coarse packing in component B is 1:(1.3-2.5).

4. The high-adhesion two-component epoxy tile adhesive according to claim 1, characterized in that, The fine filler includes activated calcium, which has an average particle size of 5-20 micrometers.

5. The high-adhesion two-component epoxy tile adhesive according to claim 1, characterized in that, The coarse filler includes calcium carbonate, and the average particle size of the calcium carbonate is 50-300 mesh.

6. The high-adhesion two-component epoxy tile adhesive according to claim 3, characterized in that, The resin has an epoxy equivalent of 150-300 g / eq and a viscosity of 100-1500 mPa·s at 25°C.

7. The high-adhesion two-component epoxy tile adhesive according to claim 3, characterized in that, The nitrogen adsorption specific surface area of ​​the hydrophilic silica is 150-250 m². 2 / g.

8. The high-adhesion two-component epoxy tile adhesive according to claim 3, characterized in that, The curing agent has an amine value of 200-300 mg KOH / g and a viscosity of 100-1000 mPa·s.

9. The high-adhesion two-component epoxy tile adhesive according to claim 8, characterized in that, The weight ratio of component A to component B is 1:(0.8-1.2).

10. A method for preparing a high-adhesion two-component epoxy tile adhesive according to any one of claims 1-9, characterized in that, The process includes the following steps: mixing the resin and fine filler in component A evenly, adding coarse filler, stirring evenly, adding hydrophilic silica, and stirring evenly under vacuum to obtain component A; mixing the curing agent, fine filler, and color powder in component B evenly, adding coarse filler, stirring evenly, adding hydrophilic silica, and stirring evenly under vacuum to obtain component B.

Images