Ceramic tile hollowing adhesive and method for preparing ceramic tile hollowing adhesive

Abstract

The invention provides a ceramic tile hollowing adhesive and a method for preparing the ceramic tile hollowing adhesive, raw materials for preparing the ceramic tile hollowing adhesive comprise a reaction monomer, an emulsifier and a water-based solvent, the reaction monomer comprises an acrylate monomer, and the method for preparing the ceramic tile hollowing adhesive adopts a secondary seed taking mode to prepare the ceramic tile hollowing adhesive. The ceramic tile hollowing adhesive comprises latex particles A with the particle size ranging from 300 nm to 450 nm and latex particles B with the particle size ranging from 50 nm to 150 nm. The ceramic tile hollowing adhesive has the characteristics of high solid content, quick drying and low curing shrinkage rate, and is high in initial bonding strength and high in long-term bonding strength.

Description

TECHNICAL FIELD

[0001] The patent belongs to the field of building materials, and specifically relates to a ceramic tile hollowing adhesive and a method for preparing the ceramic tile hollowing adhesive. BACKGROUND

[0002] With the increase of the service life of buildings and the limitation of paving technology, the problem of ceramic tile hollowing and falling off is increasingly prominent, and ceramic tile hollowing repair adhesive emerges as the times require as a key interfacial treatment material, which restores the bonding efficiency by filling the gap between the ceramic tile and the base material. In the current mainstream products on the market, the construction process of two-component ceramic tile hollowing adhesive is relatively complex, and individual users are difficult to operate to complete; although single-component emulsion type ceramic tile hollowing adhesive is simple to operate and low in cost, it has inherent defects such as poor water resistance, slow drying, insufficient initial bonding strength, and the like, and long-term use leads to mildew and stench due to the lack of antibacterial and mildew-proof performance.

[0003] In the prior art, part of the ceramic tile hollowing adhesive improves the water resistance by adding modified components, but the introduced modified components cannot play a lasting role, and cannot solve the health hazards in the long-term use; there are also part of the ceramic tile hollowing adhesive that improves the construction experience by low-viscosity design, but due to the inherent defects of the single-component system, the drying process is significantly delayed, the solidification shrinkage stress is concentrated, and the initial bonding reliability of the repaired interface is seriously affected. It is worth noting that due to the delay of material solidification kinetics, the slow drying speed directly leads to the fact that the repaired interface cannot establish sufficient bonding strength in the key forming period, and greatly increases the risk of secondary falling off of hollowing.

[0004] Developing a single-component ceramic tile hollowing adhesive with high solid content, fast drying characteristics and low shrinkage rate is an inevitable direction to solve the industry pain points. SUMMARY

[0005] The purpose of the present application is to seek a ceramic tile hollowing adhesive and a method for preparing the ceramic tile hollowing adhesive, which has high solid content, fast drying characteristics and low solidification shrinkage rate, and has high initial bonding strength and long-term bonding strength.

[0006] According to one of the applications of the present application, a method for preparing a ceramic tile hollowing adhesive is provided, raw materials for preparing the ceramic tile hollowing agent include reaction monomers, emulsifiers, aqueous solvents, the reaction monomers include acrylate monomers, and the method for preparing the ceramic tile hollowing adhesive comprises the following steps: S1. Part of the reaction monomers is mixed with part of the emulsifiers and part of the aqueous solvents to obtain a pre-emulsion A, the pre-emulsion A is reacted in a system containing an initiator to obtain a seed emulsion A; the remaining reaction monomers are mixed with the remaining emulsifiers and the remaining aqueous solvents to obtain a pre-emulsion B, and part of the pre-emulsion B is reacted in a system containing an initiator to obtain a seed emulsion B; wherein the particle size of the seed emulsion A is greater than the particle size of the seed emulsion B; S2. The seed emulsion A and the pre-emulsion B are mixed in a mass ratio of 1:0.8-1.5, the seed emulsion A and the pre-emulsion B are reacted in a system containing an initiator to obtain a ceramic tile hollowing adhesive, the ceramic tile hollowing adhesive includes latex particles A with a particle size in the range of 300-450 nm and latex particles B with a particle size in the range of 50-150 nm, the pre-emulsion B is reacted in a system containing an initiator to obtain a seed emulsion B; wherein the particle size of the seed emulsion A is greater than the particle size of the seed emulsion B.

[0007] The present application successfully constructs a composite latex particle system containing two different particle sizes (latex particles A and latex particles B) in the ceramic tile hollowing adhesive through a unique secondary seeding process, i.e., first the seed emulsion A and the seed emulsion B with different particle sizes, and then the seed emulsion A and the pre-emulsion B are co-reacted, thereby realizing precise control of the particle size of the latex particles, and enabling the small-particle-size latex particles B to fill the gaps between the large-particle-size latex particles A. At the same time, through precise control of the mixing ratio of the seed emulsion A and the pre-emulsion B, the mass ratio of the latex particles A and the latex particles B in the ceramic tile hollowing adhesive can be controlled in the optimized range of 40-60:10-20. This synergistic control of the particle size and the ratio significantly improves the solid content of the ceramic tile hollowing adhesive. Thus, during the curing process, the ceramic tile hollowing adhesive with high solid content not only has the ability to dry quickly, but also effectively reduces the drying shrinkage, thereby successfully overcoming the technical defects of the existing single-component ceramic tile back adhesive emulsion, such as low solid content, long drying time and large shrinkage, improving the construction efficiency and the final filling and repairing quality of the product.

[0008] Preferably, the particle size of the latex particles A is 350-400 nm, and the particle size of the latex particles B is 80-110 nm.

[0009] Preferably, in S1, the proportion of the pre-emulsion B used to prepare the seed emulsion B is 5.5-8.8wt% based on the pre-emulsion B.

[0010] Preferably, in S1, the particle size of the seed emulsion A is 100-200 nm.

[0011] Preferably, in S1, the process of preparing the seed emulsion A specifically comprises the following operation: at a reaction temperature of 70-80℃, the pre-emulsion A and initiator are added dropwise into the solution containing part of the emulsifier, and the dropwise speed is 2-5g / min.

[0012] In the key reaction stage of forming the seed emulsion A, by precisely regulating the synergistic effect of the reaction temperature and the monomer dropwise speed, the dynamic balance of the reaction kinetics and thermodynamics is achieved. Specifically, the combination of the reaction temperature and the dropwise speed effectively controls the reaction heat release rate: if the temperature is too high or the dropwise speed is too fast, a large amount of monomers will rush in for a short time, which will lead to a sharp increase in instantaneous heat release, and the heat dissipation lag will easily cause local overheating, thus intensifying the side reactions and reducing the uniformity of the product; on the contrary, if the temperature is too low or the dropwise speed is too slow, although the heat release pressure can be alleviated, the reaction cycle will be significantly prolonged, the production efficiency will be reduced, and the energy consumption cost will be increased. By regulating both of them to an appropriate range, the reaction is ensured to proceed smoothly, the generation of by-products is inhibited, and the process time is greatly shortened, finally the product quality is improved while the economic benefits of industrial production are significantly optimized, and the problems of poor product stability and high production cost caused by improper control of reaction conditions in the prior art are systematically overcome.

[0013] Preferably, in S2, the reaction process of the seed emulsion A and the seed emulsion B specifically comprises the following operation: at a reaction temperature of 80-90℃, part of the seed emulsion A and the seed emulsion B are first mixed according to a mass ratio of 1:0.8-1.5, and then the remaining pre-emulsion B and initiator are added dropwise into the reaction system obtained.

[0014] Preferably, the reaction monomers further include an epoxy-modified monomer, and the epoxy-modified monomer includes at least one of glycidyl methacrylate, allyl glycidyl ether, and glycidyl acrylate; at least part of the epoxy-modified monomer is included in the pre-emulsion B. By introducing the above-mentioned types of epoxy-modified monomers into the polymer molecular chain, it is beneficial to enhance the interfacial bonding performance and environmental stability of the ceramic tile hollowing adhesive. This modification design makes the polymer molecular chain have high reactive groups and hydrophobic structural units: on the one hand, the epoxy groups can form strong chemical bonding and physical anchoring with the cement hydration products and / or the ceramic tile surface, which is beneficial to improve the bonding strength of the ceramic tile hollowing adhesive to these materials; on the other hand, the hydrophobic segment can construct a hydrophobic barrier on the surface of the ceramic tile hollowing adhesive after curing, effectively blocking the penetration of environmental water molecules. This makes the ceramic tile hollowing adhesive product still maintain excellent bonding durability under high humidity or long-term humid working conditions, solving the technical defects of the existing single-component ceramic tile back adhesive, such as insufficient bonding force and easy debonding in water due to strong hydrophilicity. In addition, by introducing at least part of the epoxy-modified monomer in the pre-emulsion B, a hydrophobic structure can be formed on the outer surface of the latex particle, which is beneficial to improve the adhesion strength of the ceramic tile hollowing adhesive.

[0015] Preferably, the reaction monomer further comprises a silane coupling agent; at least a part of the silane coupling agent is included in the pre-emulsion B. The siloxane group in the silane coupling agent can be hydrolyzed to form active silanol during the curing process, and form strong covalent bonding with the hydroxyl group on the surface of the ceramic tile, thereby enhancing the bonding strength to the ceramic tile and the cement base material. At the same time, by using the hydrophobic long chain after the hydrolysis of the silane coupling agent, the penetration of environmental water molecules to the bonding interface is prevented, so that the product can still maintain excellent bonding strength retention rate under long-term humid, high-humidity or even short-term immersion working conditions. In addition, by introducing at least a part of the silane coupling agent in the pre-emulsion B, the silane coupling agent can promote the construction of a hydrophobic barrier on the outer surface of the latex particle, which is beneficial to improve the adhesive strength of the ceramic tile hollowing agent.

[0016] Preferably, the raw materials for preparing the ceramic tile hollowing agent further comprise a silica sol and nano-silver, and the mass ratio of the silica sol to the nano-silver is 3:2-4. Through the synergistic mechanism of the silica sol and the nano-silver, the molecular-level stabilization of the antibacterial component in the polymer matrix is realized. The silica sol participates in the formation of a crosslinked network during polymerization, and the nano-porous structure of the silica sol can uniformly bind silver particles in the polymer network through physical adsorption. This fixing method allows the nano-silver to be embedded in the polymer molecular chain, which is beneficial to prevent the nano-silver from falling off due to external force washing, moisture expansion and other factors, thereby losing the antibacterial component. Thus, the ceramic tile hollowing agent is endowed with durable antibacterial and mildew-proof properties, and can still maintain high protection ability in harsh environments such as humidity and alternating temperature, thereby providing long-term health protection.

[0017] Preferably, the pre-emulsion B comprises a silica sol, and the method for preparing the ceramic tile hollowing agent further comprises S3, which comprises the following operation: mixing the ceramic tile hollowing agent prepared in S2 with nano-silver at a reaction temperature of 60-80℃, and stirring for 1.5-2.5 hours. The silica sol is introduced in the pre-emulsion B stage first, so that the silica sol can fully participate in the emulsion polymerization reaction, and then the nano-silver is loaded in the subsequent synthesis stage (S3), and the silica sol is used to realize efficient adsorption and spatial confinement of silver particles. This time sequence design is beneficial to avoid the loss risk of the antibacterial component caused by physical migration or chemical degradation in the traditional process, thereby endowing the ceramic tile hollowing agent with durable and reliable antibacterial and mildew-proof properties. Even in harsh environments such as long-term moisture and alternating temperature, it can still maintain high microbial inhibition ability, thereby solving the health performance failure problem caused by the easy falling off of the antibacterial component of the existing single-component ceramic tile back adhesive.

[0018] According to another aspect of the present application, a ceramic tile hollowing agent is provided, comprising latex particles A, latex particles B, and a water-based solvent, the particle size of the latex particles A is 300-450 nm, and the particle size of the latex particles B is 50-150 nm; based on the total mass of the ceramic tile hollowing agent, the content of the latex particles A is 40-60 wt%, and the content of the latex particles B is 10-20 wt%.

[0019] By synergistically controlling the particle size distribution and mass ratio of latex particle A and latex particle B, a more dense packing structure of latex particles is achieved at the micro level. The small particle size latex particle B effectively fills the voids between the large particle size latex particle A, which can improve the solid content of the ceramic tile hollow glue system; this structural optimization makes the solvent volatilization channel more unobstructed and the shrinkage stress distribution more uniform during the curing process of the ceramic tile hollow glue, thereby simultaneously achieving the dual advantages of rapid drying and low shrinkage. Not only does it greatly shorten the construction waiting time, but it also completely eliminates the repair interface micro-cracks caused by drying shrinkage, fundamentally overcoming the technical defects of low drying efficiency, large shrinkage deformation and poor repair durability caused by the insufficient solid content of the existing single-component ceramic tile back adhesive.

[0020] Preferably, the raw materials for preparing the ceramic tile hollowing agent include reaction monomers, emulsifiers, and aqueous solvents. The reaction monomers include 700-1200 parts of acrylic ester monomers and 15-25 parts of epoxy modified monomers, and the epoxy modified monomers include at least one of glycidyl methacrylate, allyl glycidyl ether, and glycidyl acrylate.

[0021] Preferably, the raw materials for preparing the ceramic tile hollowing agent include reaction monomers, emulsifiers, and aqueous solvents. The reaction monomers include 700-1200 parts of acrylic ester monomers and 15-25 parts of epoxy modified monomers, and the epoxy modified monomers include at least one of glycidyl methacrylate, allyl glycidyl ether, and glycidyl acrylate.

[0022] Preferably, the raw materials for preparing the ceramic tile hollowing agent include reaction monomers, silicon sol, nano-silver, emulsifiers, and aqueous solvents, and the reaction monomers include acrylic ester monomers. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 Test schematic for the crack resistance of the ceramic tile hollowing adhesive. DETAILED DESCRIPTION

[0024] In order for those skilled in the art to better understand the technical solutions in the present application, the technical solutions of the present application will be described clearly and completely below in conjunction with the drawings of the embodiments and examples of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor should fall within the scope of protection of the present application.

[0025] Example 1 This embodiment prepares a ceramic tile hollowing adhesive, which is composed of the following components: Table 1. Raw material type composition of pre-emulsion A

[0026] Table 2. Raw material type composition of pre-emulsion B

[0027] The method for preparing the ceramic tile hollowing adhesive comprises the following steps: S1-1. Material preparation: prepare the materials according to the raw material composition shown in Table 1, mix, and obtain pre-emulsion A; mix 200 parts by mass of water, 2.5 parts by mass of fatty alcohol ethoxylate phosphate ester emulsifier, 1 part by mass of fatty alcohol ethoxylate emulsifier, and 1 part by mass of nonylphenol polyoxyethylene ether emulsifier to prepare an emulsifier solution; S1-2. Preparation of seed emulsion A: at a reaction temperature of 70-80°C, slowly add the pre-emulsion A and the 0.026wt% ammonium persulfate initiator solution to the emulsifier solution, and drop the pre-emulsion A within 180 minutes (the drop rate can be calculated to be in the range of 2-5g / min), so that the pre-emulsion A reacts in the system containing the initiator to obtain a seed emulsion A with a particle size in the range of 150-180nm; S1-3. Prepare the materials according to the raw material composition shown in Table 2, mix, and obtain pre-emulsion B. Take 60g of pre-emulsion B and 0.0625wt% ammonium persulfate initiator solution, mix the pre-emulsion B and the ammonium persulfate initiator solution according to a mass ratio of 6:1, and react at a reaction temperature of 85±5°C for 15 minutes to obtain seed emulsion B. The particle size of the seed emulsion A is greater than that of the seed emulsion B; S2. Mix the seed emulsion A and the pre-emulsion B according to a mass ratio of 1:1 (i.e. take 60g of seed emulsion A) at a reaction temperature of 85±5°C, and then add the remaining pre-emulsion B and 0.0625wt% ammonium persulfate initiator solution to the reaction system obtained to make the seed emulsion A and the seed emulsion B react in the system containing the initiator and the pre-emulsion B at a reaction temperature of 85±5°C to obtain a ceramic tile hollowing adhesive. The ceramic tile hollowing adhesive comprises latex particles A with a particle size in the range of 350-400nm and latex particles B with a particle size in the range of 80-110nm.

[0028] S3. Mix the ceramic tile hollowing adhesive prepared in S2 with a nano-silver solution with a mass fraction of 1wt%, and the addition amount of the nano-silver solution is such that the mass ratio of the silica sol to the nano-silver is 3:2. React at 70±2°C with a stirring speed of 100rpm for 2 hours to make the nano-silver particles and the silica sol fully adsorbed.

[0029] Example 2 This embodiment refers to the preparation method provided in embodiment 1 to prepare a ceramic tile hollowing adhesive. The difference between this embodiment and embodiment 1 is that in the process of S2 of preparing the ceramic tile hollowing adhesive, 60 g of seed emulsion A is mixed with 48 g of seed emulsion B, and then the remaining pre-emulsion B and the 0.0625 wt% ammonium persulfate initiator solution are added dropwise into the reaction system obtained. The mass ratio of seed emulsion A to seed emulsion B is 1:0.8. The rest of the raw material ratio and the preparation method are strictly the same as those in embodiment 1.

[0030] Embodiment 3 This embodiment refers to the preparation method provided in embodiment 1 to prepare a ceramic tile hollowing adhesive. The difference between this embodiment and embodiment 1 is that in the process of S2 of preparing the ceramic tile hollowing adhesive, 60 g of seed emulsion A is mixed with 48 g of seed emulsion B, and then the remaining pre-emulsion B and the 0.0625 wt% ammonium persulfate initiator solution are added dropwise into the reaction system obtained. The mass ratio of seed emulsion A to seed emulsion B is 1:0.8. The rest of the raw material ratio and the preparation method are strictly the same as those in embodiment 1.

[0031] Embodiment 4 This embodiment refers to the preparation method provided in embodiment 1 to prepare a ceramic tile hollowing adhesive. The difference between this embodiment and embodiment 1 is that in the process of S1 of preparing the ceramic tile hollowing adhesive, the proportion of pre-emulsion B used to prepare seed emulsion B is 4.7 wt% based on pre-emulsion B. That is, 40 g of pre-emulsion B is used to prepare seed emulsion B, and the remaining pre-emulsion B is added dropwise in the process of S2. The rest of the raw material ratio and the preparation method are strictly the same as those in embodiment 1. In particular, the mass ratio of seed emulsion A to seed emulsion B in S2 is kept at 1:1.

[0032] Embodiment 5 This embodiment refers to the preparation method provided in embodiment 1 to prepare a ceramic tile hollowing adhesive. The difference between this embodiment and embodiment 1 is that in the process of S1 of preparing the ceramic tile hollowing adhesive, the proportion of pre-emulsion B used to prepare seed emulsion B is 5.5 wt% based on pre-emulsion B. That is, 47 g of pre-emulsion B is used to prepare seed emulsion B, and the remaining pre-emulsion B is added dropwise in the process of S2. The rest of the raw material ratio and the preparation method are strictly the same as those in embodiment 1. In particular, the mass ratio of seed emulsion A to seed emulsion B in S2 is kept at 1:1.

[0033] Embodiment 6 This example refers to the preparation method provided in Example 1 to prepare a ceramic tile hollowing adhesive. The difference between this example and Example 1 is that in the process of preparing the ceramic tile hollowing adhesive S1, the proportion of the pre-emulsion B used to prepare the seed emulsion B is 8.8wt% based on the pre-emulsion B. That is, 75g of pre-emulsion B is used to prepare the seed emulsion B, and the remaining pre-emulsion B is added dropwise in the process of S2. The remaining raw material ratio, preparation method and Example 1 are strictly kept consistent, especially the mass ratio of seed emulsion A and seed emulsion B in S2 is kept at 1:1.

[0034] Example 7 This example refers to the preparation method provided in Example 1 to prepare a ceramic tile hollowing adhesive. The difference between this example and Example 1 is that in the process of preparing the ceramic tile hollowing adhesive S1, the proportion of the pre-emulsion B used to prepare the seed emulsion B is 8.8wt% based on the pre-emulsion B. That is, 75g of pre-emulsion B is used to prepare the seed emulsion B, and the remaining pre-emulsion B is added dropwise in the process of S2. The remaining raw material ratio, preparation method and Example 1 are strictly kept consistent, especially the mass ratio of seed emulsion A and seed emulsion B in S2 is kept at 1:1.

[0035] Example 8 This example refers to the preparation method provided in Example 1 to prepare a ceramic tile hollowing adhesive. The difference between this example and Example 1 is that in the process of preparing the ceramic tile hollowing adhesive S1, the proportion of the pre-emulsion B used to prepare the seed emulsion B is 8.8wt% based on the pre-emulsion B. That is, 75g of pre-emulsion B is used to prepare the seed emulsion B, and the remaining pre-emulsion B is added dropwise in the process of S2. The remaining raw material ratio, preparation method and Example 1 are strictly kept consistent, especially the mass ratio of seed emulsion A and seed emulsion B in S2 is kept at 1:1.

[0036] Example 9 This example refers to the preparation method provided in Example 1 to prepare a ceramic tile hollowing adhesive. The difference between this example and Example 1 is that in the process of preparing the ceramic tile hollowing adhesive S1, the proportion of the pre-emulsion B used to prepare the seed emulsion B is 8.8wt% based on the pre-emulsion B. That is, 75g of pre-emulsion B is used to prepare the seed emulsion B, and the remaining pre-emulsion B is added dropwise in the process of S2. The remaining raw material ratio, preparation method and Example 1 are strictly kept consistent, especially the mass ratio of seed emulsion A and seed emulsion B in S2 is kept at 1:1.

[0037] Example 10 This example refers to the preparation method provided in Example 1 to prepare a ceramic tile hollowing adhesive. The difference between this example and Example 1 is that in the process of preparing the ceramic tile hollowing adhesive S1, the proportion of the pre-emulsion B used to prepare the seed emulsion B is 8.8wt% based on the pre-emulsion B. That is, 75g of pre-emulsion B is used to prepare the seed emulsion B, and the remaining pre-emulsion B is added dropwise in the process of S2. The remaining raw material ratio, preparation method and Example 1 are strictly kept consistent, especially the mass ratio of seed emulsion A and seed emulsion B in S2 is kept at 1:1.

[0038] Comparative Example 1 The counter example refers to the preparation method provided in Example 1 to prepare a ceramic tile hollowing adhesive. The difference between the counter example and Example 1 is that the secondary seeding method is not used in the process of preparing the ceramic tile hollowing adhesive. Specifically, the operation of S1 is omitted, and 200 parts by mass of water is reserved as the reaction base material. Then, the raw materials shown in Table 2 are prepared, mixed, and a pre-emulsion B is obtained. Then, referring to the operation of S2, the pre-emulsion B and an ammonium persulfate initiator solution with a concentration of 0.0625wt% are added dropwise into the reaction base material (water) at a reaction temperature of 85±5℃. The system containing the initiator and the pre-emulsion B is reacted at a reaction temperature of 85±5℃ to obtain latex particles B with a particle size in the range of 80-110nm. The remaining raw material proportions are strictly consistent with Example 1.

[0039] Counter Example 2 The counter example refers to the preparation method provided in Example 1 to prepare a ceramic tile hollowing adhesive. The difference between the counter example and Example 1 is that in the process of preparing the ceramic tile hollowing adhesive S2, 60g of seed emulsion A is mixed with 30g of seed emulsion B, and then the remaining pre-emulsion B and an ammonium persulfate initiator solution with a concentration of 0.0625wt% are added dropwise into the reaction system obtained. The mass ratio of seed emulsion A to seed emulsion B is 1:0.5. The remaining raw material proportions and preparation methods are strictly consistent with Example 1.

[0040] Counter Example 3 The counter example refers to the preparation method provided in Example 1 to prepare a ceramic tile hollowing adhesive. The difference between the counter example and Example 1 is that in the process of preparing the ceramic tile hollowing adhesive S2, 60g of seed emulsion A is mixed with 120g of seed emulsion B, and then the remaining pre-emulsion B and an ammonium persulfate initiator solution with a concentration of 0.0625wt% are added dropwise into the reaction system obtained. The mass ratio of seed emulsion A to seed emulsion B is 1:2. The remaining raw material proportions and preparation methods are strictly consistent with Example 1.

[0041] Test Example 1 Test object: ceramic tile hollowing adhesives provided in Examples 1-10 and Counter Examples 1-3.

[0042] Test items: (1) Polymerization stability: If obvious polymerization explosion, polymerization failure, gelation, abnormal viscosity, stringing, and clumping occur during the preparation of the ceramic tile hollowing adhesive, it is considered to be unstable and unable to prepare the ceramic tile hollowing adhesive, recorded as "unstable". If there is no such situation, the polymerization is stable, recorded as "stable".

[0043] (2) Anti-cracking: Two 0.7mm iron wires are cut and placed parallel on the mortar block with an interval of about 5cm. About 1.5g of tile hollowing adhesive is cut in the middle of the two iron wires and spread into a circular pattern of about 3cm. A glass plate is pressed on the mortar block, and due to the presence of the iron wires, there is a constant 0.7mm gap between the glass plate and the mortar block, which is filled with the tile hollowing adhesive. After drying, after 7 days, the shrinkage can be observed by naked eye, and specifically, the ratio of the area after drying shrinkage to the area before drying shrinkage, the shrinkage rate = (the area before drying - the area after drying shrinkage) / the area before drying x 100%. Figure 1

[0044] (3) Early bonding strength: The tile adhesive is coated on the mortar block, and the tile is adhered to the mortar block. After one day, it is pried off and cured for six days. The tile hollowing adhesive is sprayed on the surface of the mortar block, and the tile is pressed on the surface of the tile hollowing adhesive, so that the tile hollowing adhesive overflows to ensure that the inside is fully filled. Then the excess tile hollowing adhesive is removed, and a 2kg weight is pressed for one day to allow the tile hollowing adhesive to solidify and dry. Then it is left to stand at 25°C for 7 days. The tensile force required to separate the mortar block and the tile adhesive is recorded using a tensile testing machine.

[0045] (4) Long-term bonding strength: The tile adhesive is coated on the mortar block, and the tile is adhered to the mortar block. After one day, it is pried off and cured for six days. The tile hollowing adhesive is sprayed on the surface of the mortar block, and the tile is pressed on the surface of the tile hollowing adhesive, so that the tile hollowing adhesive overflows to ensure that the inside is fully filled. Then the excess tile hollowing adhesive is removed, and a 2kg weight is pressed for one day to allow the tile hollowing adhesive to solidify and dry. Then it is left to stand at 25°C for 21 days. The tensile force required to separate the mortar block and the tile adhesive is recorded using a tensile testing machine.

[0046] (5) Tensile bonding strength after immersion: The tile adhesive is coated on the mortar block, and the tile is adhered to the mortar block. After one day, it is pried off and cured for six days. The tile hollowing adhesive is sprayed on the surface of the mortar block, and the tile is pressed on the surface of the tile hollowing adhesive, so that the tile hollowing adhesive overflows to ensure that the inside is fully filled. Then the excess tile hollowing adhesive is removed, and a 2kg weight is pressed for one day to allow the tile hollowing adhesive to solidify and dry. Then it is left to stand at 25°C for 14 days. The tile hollowing adhesive and the cement base are immersed in deionized water for 7 days. The tensile force required to separate the mortar block and the tile adhesive is recorded using a tensile testing machine.

[0047] (6) Long-term antibacterial property: Referring to the test method provided in "GB / T 21866-2008 Antibacterial Coatings (Paint Film) Antibacterial Property Determination Method and Antibacterial Effect", the substrate is a mortar block, and the long-term antibacterial property of the tile hollowing adhesive is tested.

[0048] Test results: As shown in Table 3.

[0049] ​Table 3. Performance indicators of the tile hollowing glue in the test example

[0050] Result analysis: By comparing the performance indicators of Example 1 and Comparative Example 1, Example 1 using the secondary seeding process has higher early and long-term bonding strength, and higher bonding strength after immersion, which shows that the tile hollowing glue including latex particles A with a particle size in the range of 300-450 nm and latex particles B with a particle size in the range of 50-150 nm, by filling the gap between large particles with small particles, not only has the ability to dry quickly, but also effectively reduces the drying shrinkage, thereby maintaining a low shrinkage rate of 20±5% while achieving high solid content, fast drying and strong bonding performance.

[0051] By comparing the performance data of Examples 1-3 and Comparative Examples 2-3, it can be found that as the ratio of seed emulsion A to seed emulsion B increases, the polymerization stability of the tile hollowing glue shows a trend of first unstable, then stable, and then unstable. When the seed emulsion A and the seed emulsion B are mixed in a mass ratio of 1:0.8-1.5, the early bonding strength, long-term bonding strength and bonding strength after immersion of the tile hollowing glue are higher, and the polymerization stability is good. If the mixing ratio of seed emulsion A and seed emulsion B is too small or too large, the polymerization system is prone to polymerization instability.

[0052] By comparing the performance data of Example 1 and Examples 4-7, it can be found that as the proportion of pre-emulsion B used to prepare seed emulsion B increases, the early bonding strength of the tile hollowing glue shows an upward trend, and the bonding strength of the tile hollowing glue after immersion shows a downward trend. When the proportion of pre-emulsion B used to prepare seed emulsion B is 5.5-8.8wt based on pre-emulsion B in S1, the comprehensive bonding performance of the tile hollowing glue is better.

[0053] By comparing the performance data of Example 1 and Examples 8-9, it can be found that the early bonding strength, long-term bonding strength and bonding strength after immersion of the tile hollowing glue provided by Example 1 are all higher than those of the tile hollowing glue provided by Examples 8-9. This shows that introducing an epoxy modified monomer and / or a silane coupling agent into the tile hollowing glue can effectively improve the adhesion strength of the tile hollowing glue.

[0054] By comparing the performance data of Example 1 with Example 10, it can be found that the ceramic tile hollowing adhesive provided by Example 1 and Example 10 both have good antibacterial performance in the early stage, but compared with Example 10, the ceramic tile hollowing adhesive of Example 1 has better long-term antibacterial property. This is because the silica sol is used in Example 1 to fix the nano-silver in the polymer network of the ceramic tile hollowing adhesive, thereby endowing the ceramic tile hollowing adhesive with persistent antibacterial and mildew-proof performance. In Example 10, no silica sol is used, so the combination between the nano-silver and the polymer network of the ceramic tile hollowing adhesive is not tight enough, and the nano-silver is easy to fall off in the long-term use process.

[0055] Example 11 1、 This embodiment refers to the preparation method provided by Example 1 to prepare a ceramic tile hollowing adhesive. The difference between this embodiment and Example 1 is that the raw material composition shown in Table 4 is used to prepare pre-emulsion A, and the raw material composition shown in Table 5 is used to prepare pre-emulsion B. The rest of the raw material ratio, preparation method and Example 1 are strictly kept consistent.

[0056] Table 4. Raw material type composition of pre-emulsion A

[0057] Table 5. Raw material type composition of pre-emulsion B

[0058] 2、 The ceramic tile hollowing adhesive is tested by using the test method in Test Example 1.

[0059] Test results: The ceramic tile hollowing adhesive provided by Example 11 has stable polymerization, the measured shrinkage rate is 20±5%, the early bonding strength is >0.7Mpa, the long-term bonding strength is >0.9Mpa, the bonding strength after immersion is >0.7Mpa, and the long-term antibacterial property is >95%.

[0060] The above examples are only used to illustrate the technical solutions of the present application and not to limit the protection scope of the present application. Although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or replaced by equivalents without departing from the essence and scope of the technical solutions of the present application.

Claims

1. A method of preparing a tile hollowing adhesive, characterized by, The raw materials for preparing the ceramic tile hollowing agent include reaction monomers, emulsifiers, and aqueous solvents, the reaction monomers include acrylate monomers, The method for preparing the ceramic tile hollowing glue includes the following steps: S1. Part of the reaction monomers is mixed with part of the emulsifiers and part of the aqueous solvents to obtain a pre-emulsion A, the pre-emulsion A is reacted in a system containing an initiator to obtain a seed emulsion A; the remaining reaction monomers are mixed with the remaining emulsifiers and the remaining aqueous solvents to obtain a pre-emulsion B, part of the pre-emulsion B is taken and reacted in a system containing an initiator to obtain a seed emulsion B; wherein the particle size of the seed emulsion A is larger than the particle size of the seed emulsion B; S2. Part of the seed emulsion A is mixed with the seed emulsion B according to a mass ratio of 1:0.8-1.5, the seed emulsion A and the seed emulsion B are reacted in a system containing an initiator and the remaining pre-emulsion B to obtain the ceramic tile hollowing glue, the ceramic tile hollowing glue includes latex particles A with a particle size in the range of 300-450 nm and latex particles B with a particle size in the range of 50-150 nm.

2. The method for preparing the ceramic tile hollowing glue according to claim 1, characterized in that, In the S1, the proportion of the pre-emulsion B used for preparing the seed emulsion B is 5.5-8.8wt% based on the pre-emulsion B.

3. The method for preparing the ceramic tile hollowing glue according to claim 1, characterized in that, In the S1, the process for preparing the seed emulsion A specifically includes the following operation: at a reaction temperature of 70-80℃, the pre-emulsion A and the initiator are added dropwise into a solution containing part of the emulsifiers, and the dropwise speed is 2-5g / min; And / or, in the S2, the reaction process of the seed emulsion A and the seed emulsion B specifically includes the following operation: at a reaction temperature of 80-90℃, part of the seed emulsion A is first mixed with the seed emulsion B according to a mass ratio of 1:0.8-1.5, and then the remaining pre-emulsion B and the initiator are added dropwise into the reaction system obtained.

4. The method for preparing tile hollow adhesive as described in claim 1, characterized in that, The reaction monomers further include epoxy modified monomers, the epoxy modified monomers include at least one of glycidyl methacrylate, allyl glycidyl ether, and glycidyl acrylate; at least part of the epoxy modified monomers are included in the pre-emulsion B.

5. The method for preparing tile hollow adhesive as described in claim 1, characterized in that, The reaction monomers further include silane coupling agents; at least part of the silane coupling agents are included in the pre-emulsion B.

6. The method for preparing tile hollow adhesive as described in claim 1, characterized in that, The raw materials for preparing the ceramic tile hollowing agent further include silica sol and nano-silver, and the mass ratio of the silica sol to the nano-silver is 3:2-4.

7. The method for preparing tile hollow adhesive as described in claim 6, characterized in that, The pre-emulsion B includes the silica sol, and the method for preparing the ceramic tile hollowing glue further includes S3, the S3 includes the following operation: at a reaction temperature of 60-80℃, the ceramic tile hollowing glue prepared in the S2 is mixed with the nano-silver, and stirring is performed for 1.5-2.5 hours.

8. A tile hollowing adhesive, characterized by, The raw materials for preparing the ceramic tile hollowing agent include reaction monomers, emulsifiers and aqueous solvents, wherein the reaction monomers include acrylate monomers; the ceramic tile hollowing adhesive includes latex particles A, latex particles B and aqueous solvents, wherein the latex particles A have a particle size of 300-450 nm, and the latex particles B have a particle size of 50-150 nm.

9. The tile hollowing adhesive as claimed in claim 8, wherein, The content of the latex particles A is 40-60 wt% based on the total mass of the ceramic tile hollowing adhesive, and the content of the latex particles B is 10-20 wt%.

10. A method of applying a tile hollowing adhesive, characterized by, The ceramic tile hollowing adhesive includes the ceramic tile hollowing adhesive prepared by the method according to any one of claims 1-7 or the ceramic tile hollowing adhesive according to any one of claims 8-9. The application method includes the following steps: spraying the ceramic tile hollowing adhesive on the surface of a substrate, and then curing to form a coating.

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