Early-strength ceramic tile adhesive for fabricated buildings and preparation method thereof

Abstract

The application relates to an early-strength ceramic tile glue suitable for fabricated buildings, raw materials of the early-strength ceramic tile glue include, in parts by weight, cement 20-50 parts, mineral admixture 4-12 parts, graded aggregate 50-95 parts, glue powder 1-6 parts, early-strength agent 0.01-0.1 part, thickening agent 0.01-0.05 part, high water absorption resin 0.03-0.12 part, short-cut fiber 0.3-2 parts and water 20-65 parts; the particle size of particles in the graded aggregate is between 2.36 mm and 0.020 mm; in the graded aggregate, the content of particles with a particle size greater than 0.080 mm is not more than 80%, the content of particles with a particle size greater than 0.170 mm is not less than 58%, and the content of particles with a particle size greater than 0.800 mm is not more than 38%; the high water absorption resin can absorb 100-400 times the weight of the high water absorption resin; the particle size of the high water absorption resin is 180 mu m-420 mu m. The early-strength ceramic tile glue solves the problem that, in the prior art, after ceramic tiles are laid on fabricated building modules using cement-based ceramic tile glue, the ceramic tiles are prone to hollowing, falling off and displacement due to disturbance in the transportation and hoisting process.

Description

Technical Field

[0001] This invention relates to the field of building materials technology, and in particular to an early-strength ceramic tile adhesive suitable for prefabricated buildings and its preparation method. Background Technology

[0002] Tiles, as a common decorative material, are widely used in the decoration of interior and exterior walls and floors. Traditional tile laying is usually carried out on the construction site, where workers use tile adhesive to bond each tile to the work surface, completing the tile installation process. Cement-based tile adhesive is widely used due to its low cost, wide applicability, durability, and high breathability. With the rapid development of prefabricated building technology in recent years, tiles can also be directly laid onto prefabricated building modules in prefabrication factories. After the tiled prefabricated building modules are transported to the construction site, simple assembly is all that's needed to complete the construction of the entire building.

[0003] However, after prefabricated building modules are manufactured in the prefabrication plant, they often require multiple transportation and hoisting operations before assembly. Existing cement-based tile adhesives are prone to delamination or cracking due to disturbances during transportation and hoisting (which may generate significant vibrations and impacts), leading to problems such as tile hollowing, detachment, and displacement. Furthermore, due to time constraints and site limitations, tiles are often quickly transported to the construction site after being laid in the prefabricated building factory (storage time is generally no more than 2-3 days), resulting in insufficient curing time for the tile adhesive and low bonding strength. This early lack of strength further exacerbates problems such as tile hollowing, detachment, and displacement during transportation, affecting the installation weight and durability of the tiles.

[0004] It's worth noting that in the existing production and operation processes of prefabricated building factories, to ensure that the tile adhesive in the prefabricated building modules has a certain early strength when it leaves the factory, and to avoid problems such as a large number of tiles cracking, falling off, or shifting after transportation, the cement content in the tile adhesive is generally increased, or a large amount of early-strength agent and water-reducing agent are used to obtain tile adhesive with sufficient early strength. However, this type of tile adhesive is more expensive, but its later strength is relatively low. At the same time, this method of simply increasing the early strength of tile adhesive is not very compatible with prefabricated buildings. Although its early strength development and hardening are rapid, which can reduce visible problems such as tile falling off and shifting, it also means that the cement will release a large amount of concentrated heat of hydration during the intense hydration process. This will cause the tile adhesive layer to shrink drastically, resulting in invisible defects such as cracks and localized adhesion failure, affecting the later strength of the tile adhesive. Vibration and collisions during the transportation of prefabricated buildings can exacerbate these defects, such as turning micro-cracks into large cracks and causing hollow tiles at the large cracks. This further aggravates problems such as hollow tiles caused by disturbances during transportation and hoisting, and localized failure of tile adhesive bonding. Consequently, the durability and sealing performance of the tile adhesive are significantly reduced, which is not conducive to the long-term use of the tile adhesive. Summary of the Invention

[0005] (a) Technical problems to be solved

[0006] In view of the above-mentioned shortcomings and deficiencies of the prior art, the present invention provides a tile adhesive suitable for prefabricated buildings and its preparation method, which solves the problems existing in the prior art where the use of cement-based tile adhesive to lay tiles in prefabricated building modules easily leads to tile hollowing, falling off, and displacement due to disturbance during transportation and hoisting.

[0007] (II) Technical Solution

[0008] To achieve the above objectives, the main technical solutions adopted by the present invention include:

[0009] In a first aspect, the present invention provides an early-strength tile adhesive suitable for prefabricated buildings, characterized in that, by weight, the raw materials of the early-strength tile adhesive include: 20-50 parts of cement, 4-12 parts of mineral admixtures, 50-95 parts of graded aggregates, 1-6 parts of adhesive powder, 0.01-0.1 parts of early-strength agent, 0.01-0.05 parts of thickener, 0.03-0.12 parts of superabsorbent resin, 0.3-2 parts of chopped fibers, and 20-65 parts of water;

[0010] The particle size of the graded aggregate is between 2.36mm and 0.020mm; in the graded aggregate, the content of particles with a particle size greater than 0.080mm does not exceed 80%, the content of particles with a particle size greater than 0.170mm is not less than 58%, and the content of particles with a particle size greater than 0.800mm does not exceed 38%.

[0011] Superabsorbent polymers can absorb 100-400 times their own weight in water; the particle size of superabsorbent polymers is 180μm-420μm.

[0012] Early strength agents include at least one of nitrate early strength agents, carbonate early strength agents, organic early strength agents, and sulfate early strength agents.

[0013] Optionally, by weight, the raw materials of early-strength tile adhesive include: 30-45 parts cement, 6-10 parts mineral admixtures, 60-80 parts graded aggregates, 2-4 parts adhesive powder, 0.02-0.06 parts early-strength agent, 0.01-0.02 parts thickener, 0.05-0.1 parts superabsorbent resin, 0.5-1 parts chopped fibers, and 25-55 parts water;

[0014] The mineral admixture is a mineral admixture made of clay minerals; in the graded aggregate, the content of particles with a particle size of 0.020mm-0.080mm is 20-28wt%, the content of particles with a particle size of 0.080mm-0.170mm is 10-14wt%, the content of particles with a particle size of 0.170mm-0.800mm is 25-35wt%, and the content of particles with a particle size of 0.800mm-2.36mm is 30-38wt%; the superabsorbent resin can absorb 250-350 times its own weight in water; the particle size of the superabsorbent resin is 220μm-380μm; the accelerator includes nitrate accelerator, carbonate accelerator and organic accelerator; the cement is silicate cement and / or ordinary silicate cement.

[0015] Optionally, the superabsorbent resin includes at least one of sodium polyacrylate, polyacrylamide, polyvinyl alcohol-grafted acrylate, cellulose-grafted acrylate, and acrylic acid-acrylamide copolymer.

[0016] Optionally, the cement is at least one of P.Ⅱ.52.5, P.Ⅱ.42.5, P.Ⅱ.52.5R, P.Ⅱ.42.5R, PO42.5 and PO52.5; the particle size of the cement does not exceed 80μm; and the specific surface area of ​​the cement is 350-450m2 / kg.

[0017] Optionally, the specific surface area of ​​the mineral admixture is 22-28 m². 2 / g; Mineral admixtures include at least one of kaolin powder, metakaolin powder, bentonite powder, sepiolite powder, and illite powder.

[0018] Optionally, the graded aggregate includes at least one of river sand, lake sand, mountain sand, quartz sand, granite sand, basalt sand, and recycled sand.

[0019] Optionally, the adhesive powder includes at least one of ethylene-vinyl acetate copolymer adhesive powder, acrylate adhesive powder, polyvinyl acetate adhesive powder, styrene-butadiene adhesive powder, polyvinyl alcohol adhesive powder, polyurethane adhesive powder, and starch ether adhesive powder.

[0020] Optionally, the early strength agent includes at least one of calcium formate, lithium carbonate, lithium nitrate, and calcium nitrate.

[0021] Optionally, the thickener is a cellulose-based thickener; the cellulose-based thickener includes at least one of hydroxypropyl methylcellulose, methylcellulose, hydroxymethylcellulose, and hydroxyethylcellulose; the viscosity of the cellulose-based thickener is 90,000-110,000 Pa·s; the chopped fibers are wood fibers; the length of the wood fibers is 4-8 mm; and the diameter of the wood fibers does not exceed 40 μm.

[0022] Secondly, the present invention also provides a method for preparing early-strength tile adhesive, comprising the following steps:

[0023] S1: Prepare raw materials according to the proportions of raw materials for early-strength tile adhesive suitable for prefabricated buildings as described in any one of the first aspects, and mix the superabsorbent resin with 10%-20% water to obtain a superabsorbent resin gel.

[0024] S2: Mix the early strength agent, thickener and the remaining 80%-90% water to obtain a wet material;

[0025] S3: Mix cement, mineral admixtures, graded aggregates, adhesive powder, and chopped fibers to obtain dry material;

[0026] S4: Mix and stir the superabsorbent resin gel, dry material and wet material to obtain an early-strength tile adhesive suitable for prefabricated buildings.

[0027] (III) Beneficial Effects

[0028] The beneficial effects of this invention are as follows: Because the early-strength tile adhesive of this invention uses an optimized formula of cement + graded aggregate + early-strength agent + superabsorbent resin + wood fiber, the superabsorbent resin used in the formula has excellent water retention capacity. Compared with the prior art, the superabsorbent resin can gradually release water at a relatively stable rate, allowing the early-strength tile adhesive of this invention to maintain internal humidity for a longer period. This significantly reduces the pressure on the capillary walls formed during internal hydration, resulting in less early shrinkage and less susceptibility to cracking. Maintaining internal humidity for a long time also stabilizes the internal temperature, preventing bonding failure or hollowing caused by concentrated cement hydration heat, which is beneficial for the continuous and uniform hydration of concrete, making cement hydration more uniform and improving its later strength. Simultaneously, the formula of this invention also uses a combination of graded aggregate and early-strength agent. The graded aggregate, through the combination of particles of different sizes, can improve the density, flowability, and bonding strength of the early-strength tile adhesive of this invention, reducing its shrinkage rate and cracking risk. Furthermore, the graded aggregate can work in conjunction with the early-strength agent to further improve the early strength of the early-strength tile adhesive of this invention. The combination of early-strength agent and graded aggregate can significantly improve the early hydration rate and early strength of the early-strength tile adhesive of the present invention without using a large amount of cement and early-strength agent. This results in the tile adhesive having high bonding strength when the prefabricated building leaves the factory, reducing the occurrence of problems such as tile detachment, displacement or hollowing. Detailed Implementation

[0029] To better explain and facilitate understanding of the present invention, the present invention will be described in detail below through specific embodiments.

[0030] This invention proposes an early-strength tile adhesive suitable for prefabricated buildings. By weight, the raw materials of the early-strength tile adhesive include: 20-50 parts cement, 4-12 parts mineral admixtures, 50-95 parts graded aggregates, 1-6 parts adhesive powder, 0.01-0.1 parts early-strength agent, 0.01-0.05 parts thickener, 0.03-0.12 parts superabsorbent resin, 0.3-2 parts chopped fibers, and 20-65 parts water.

[0031] The particle size of the graded aggregate is between 2.36mm and 0.020mm; in the graded aggregate, the content of particles with a particle size greater than 0.080mm does not exceed 80%, the content of particles with a particle size greater than 0.170mm is not less than 58%, and the content of particles with a particle size greater than 0.800mm does not exceed 38%.

[0032] Superabsorbent polymers can absorb 100-400 times their own weight in water. The particle size of superabsorbent polymers is 180μm-420μm.

[0033] Early strength agents include at least one of nitrate early strength agents, carbonate early strength agents, organic early strength agents, and sulfate early strength agents.

[0034] Preferably, the raw materials of the early-strength tile adhesive, by weight, include: 30-45 parts cement, 6-10 parts mineral admixtures, 60-80 parts graded aggregates, 2-4 parts adhesive powder, 0.02-0.06 parts early-strength agent, 0.01-0.02 parts thickener, 0.05-0.1 parts superabsorbent resin, 0.5-1 parts chopped fibers, and 25-55 parts water.

[0035] Mineral admixtures are mineral admixtures made from clay minerals as raw materials.

[0036] In the graded aggregate, the content of particles with a diameter of 0.020mm-0.080mm is 20-28wt%, the content of particles with a diameter of 0.080mm-0.170mm is 10-14wt%, the content of particles with a diameter of 0.170mm-0.800mm is 25-35wt%, and the content of particles with a diameter of 0.800mm-2.36mm is 30-38wt%.

[0037] Superabsorbent polymers can absorb 250-350 times their own weight in water; the particle size of superabsorbent polymers is 220μm-380μm.

[0038] Accelerators include nitrate accelerators, carbonate accelerators, and organic accelerators. The cement is at least one of silicate cement and ordinary silicate cement.

[0039] In particular, since the early-strength tile adhesive of the present invention contains an early-strength agent, it can improve the hydration rate of cement hydration and increase the development speed of early-strength tile adhesive and bonding strength.

[0040] It should be noted that the early-strength agent in the early-strength tile adhesive of this invention can be a nitrate-based early-strength agent, a carbonate-based early-strength agent, an organic early-strength agent, or a sulfate-based early-strength agent, such as calcium formate, lithium carbonate, lithium nitrate, calcium nitrate, and sodium sulfate. However, it cannot be an early-strength agent containing chloride ions, such as chloride-type early-strength agents like calcium chloride. Chloride ions may cause a significant decrease in the water absorption rate and durability of the superabsorbent resin and may corrode the steel reinforcement in the wall. The early-strength agent used in the early-strength tile adhesive of this invention can also be a CSH (hydrated calcium silicate) nucleating agent, but this is more expensive and generally not used.

[0041] This invention also employs graded aggregates formed by mixing fine aggregates of multiple particle size ranges with a large amount of micro-powder with smaller particle sizes. This graded aggregate, through the coordination of particles of different sizes, improves the density, flowability, and bond strength of the early-strength tile adhesive, while reducing its shrinkage rate and cracking risk. Simultaneously, the graded aggregates can work in conjunction with an accelerator. The dense structure of the graded aggregates reduces structural defects generated during aggregate accumulation, reduces moisture evaporation, and creates an efficient reaction environment for the accelerator, resulting in more uniform dispersion of the accelerator. The hydration products generated under the action of the accelerator can quickly fill the gaps in the graded aggregates, further improving the early strength development speed of the early-strength tile adhesive. The combination of the accelerator and the graded aggregates can significantly improve the early hydration rate and early strength of the early-strength tile adhesive without using large amounts of cement and accelerators. This results in high bond strength of the tile adhesive when prefabricated buildings leave the factory, reducing problems such as tile detachment, displacement, or hollow areas.

[0042] Specifically, the particle size range of the graded aggregate of the present invention includes four ranges: very fine particles (0.020mm-0.080mm, accounting for 20-28wt%), fine particles (0.080mm-0.170mm, accounting for 10-14wt%), medium particles (0.170mm-0.800mm, accounting for 25-35wt%), and coarse particles (0.800mm-2.36mm, accounting for 30-38wt%).

[0043] The ultrafine particles have a filling effect, capable of filling the tiny pores in the cement paste, strengthening the interfacial bonding of cement hydration products, increasing density, and enhancing the bonding strength between the early-strength tile adhesive of this invention and the tile and substrate (after tile installation, a three-layer structure is formed: tile-tile adhesive layer-substrate, where the substrate is the wall, bottom, or other surface to be tiled), reducing shrinkage and hollow areas. The ultrafine particles also have water-retention and lubricating properties, adjusting the open time of the early-strength tile adhesive, improving its lubricity, and enhancing its application. However, excessively high ultrafine particle content significantly increases the water demand of the tile adhesive, leading to decreased strength and shrinkage cracking.

[0044] Fine particles act as a transitional component, optimizing the flowability of the early-strength tile adhesive of this invention, reducing internal frictional resistance, improving its application, and enhancing its plasticity. Fine particles also provide localized mechanical support, preventing excessive aggregation of ultrafine particles that could form weak zones. If the content of fine particles is too low, it may cause discontinuous aggregate gradation, leading to poor flowability of the early-strength tile adhesive; if the content of fine particles is too high, it may reduce the density of the early-strength tile adhesive.

[0045] The presence of medium-sized particles as the main skeletal structure enhances the compressive strength and impact resistance of the early-strength tile adhesive of this invention. These medium-sized particles can also combine with fine and ultrafine particles to form a densely packed structure. This stable particle size distribution reduces drying shrinkage, controls the shrinkage rate of the early-strength tile adhesive, and reduces its porosity after curing, preventing tiles from becoming hollow and detaching. Insufficient medium-sized particle content leads to a loose skeleton, resulting in decreased impact resistance and strength of the cured tile adhesive.

[0046] The coarse particles act as a macroscopic skeletal support, providing rigid support to resist external loads and deformation. A crucial aspect of this support is that, because the particle size of the coarse particles is significantly larger than that of the superabsorbent polymer (SAP) used in the early-strength tile adhesive of this invention, even after the SAP absorbs water and expands, its particle size will not exceed that of the coarse particles. This ensures that the support effect of the coarse particles is not affected, reducing the impact of SAP volume changes on the internal stress of the early-strength tile adhesive and preventing SAP from affecting the contact between the adhesive and the tile / substrate, thus preventing localized weakening of the bond. Furthermore, since the coefficient of thermal expansion of the coarse particles is generally lower than that of cement itself, it also reduces the impact of thermal effects such as hydration heat on cement expansion and contraction, minimizing the risk of cracking caused by temperature changes, especially the risks associated with expansion and contraction during cement hydration. If the coarse particle content is too low or the particle size is too small, sufficient support cannot be achieved, which may cause the highly absorbent resin to squeeze the tile or substrate, resulting in a decrease in the local adhesion of the early-strength tile adhesive of this invention, excessive changes in internal stress, and consequently, cracking or hollowing of the adhesive layer after curing. If the coarse particle content is too high or the particle size is too large, it will reduce the uniformity of the thickness of the tile adhesive layer formed after curing, resulting in uneven tile adhesion and problems such as hollowing.

[0047] When using, the total weight fraction of ultrafine, fine, medium and coarse particles should not be less than 99 wt%. A portion of particles with a diameter less than 0.020 mm is allowed in the graded aggregate, but their weight fraction should not exceed 1 wt%. Particles with a diameter greater than 2.36 mm should be screened out, otherwise it may easily cause problems such as stress concentration and cement hydration interface defects.

[0048] The early-strength tile adhesive of this invention also contains superabsorbent polymer (SAP) that is formulated in conjunction with the early-strength agent and graded aggregates. Superabsorbent polymer is a general term for a class of high molecular polymers. These high molecular compounds have a special three-dimensional cross-linked structure, which can absorb and store a large amount of water within its structure, thus exhibiting excellent water retention capacity.

[0049] Superabsorbent polymers (SAPs) can control the rate at which free water in tile adhesive participates in the cement hydration reaction. When SAPs are added to early-strength tile adhesive, the water absorbed by the SAPs can be stably released during cement hydration after a large amount of external free water has been consumed.

[0050] Specifically, in the preparation of the early-strength tile adhesive of the present invention, the superabsorbent polymer (SAP) can absorb and store a large amount of free water from the raw materials. The free water not stored by the SAP undergoes a vigorous hydration reaction with the cement under the action of the early-strength agent and graded aggregates. This allows the early-strength tile adhesive of the present invention to hydrate rapidly in the early stages, resulting in higher early strength. Rapid hydration requires a large amount of free water. Once the free water not stored by the SAP is largely consumed, the tile adhesive needs to rely on the free water stored in the SAP for continued hydration. At this time, the SAP will stably and slowly release the stored free water, maintaining the internal humidity of the early-strength tile adhesive within a certain range. This slows down the rate at which cement particles contact free water, reduces the hydration rate, and prolongs the hydration time, allowing the cement to undergo continuous and slow hydration. This improves the durability and bonding strength of the tile adhesive, resulting in higher long-term strength, greater durability, and a longer service life. Furthermore, this slow hydration also endows the tile adhesive with a certain degree of self-healing ability. When disturbances during transportation cause defects such as microcracks in the tile adhesive layer, it can be compensated and repaired to a certain extent.

[0051] Meanwhile, after the superabsorbent resin is uniformly mixed into the tile adhesive, its ability to release moisture and maintain the humidity inside the tile adhesive can effectively reduce the pressure of the capillary walls formed during cement hydration, reduce the shrinkage during cement hydration, especially reduce the early shrinkage of the early-strength tile adhesive of the present invention, avoid excessive or concentrated shrinkage that could cause cracks in the tile adhesive layer after use, improve the bonding strength of the early-strength tile adhesive of the present invention, and avoid bonding failure.

[0052] Furthermore, because the early-strength tile adhesive of the present invention develops its early strength rapidly under the action of the early-strength agent and graded aggregate, it generates a high heat of hydration. The highly absorbent resin, which stores a large amount of water, can also disperse the heat release and adjust the temperature gradient in the early-strength tile adhesive by releasing water and regulating water evaporation, thereby reducing the impact of the early-strength tile adhesive's heat of hydration and avoiding problems such as bonding failure or cracking caused by excessively high or concentrated heat of hydration.

[0053] It is important to note that the amount and water absorption rate of the superabsorbent polymer (SAP) must be strictly controlled. Excessive SAP addition and water absorption rate will cause it to absorb a large amount of free water, slowing down the early-strength tile adhesive's hydration process and preventing it from quickly reacting with the large amount of free water, resulting in poor strength development and incomplete bonding. Conversely, insufficient SAP addition and water absorption rate will result in the SAP lacking sufficient water retention capacity, leading to a decline in the later performance of the early-strength tile adhesive. It may also cause excessively high or concentrated heat of hydration, resulting in significant shrinkage, cracks in the adhesive layer, and a decrease in the smoothness and bonding strength of the adhesive layer. In the early-strength tile adhesive of this invention, the SAP's water absorption rate is controlled to be able to absorb 100-400 times its own weight in water, with an addition amount of 0.03-0.12 parts; preferably, the water absorption rate is able to absorb 250-350 times its own weight in water, with an addition amount of 0.05-0.1 parts. Within this range, the water retention capacity of the superabsorbent resin can be effectively controlled, ensuring the stability of the superabsorbent resin's effect and providing a certain degree of tolerance for the preparation process of the tile adhesive of the present invention, avoiding the occurrence of excessive superabsorbent resin.

[0054] The particle size range of the superabsorbent polymer (SAP) also needs to be controlled. If the particle size is too small, the SAP will lose water too quickly, making it difficult to effectively control the strength development rate of the early-strength tile adhesive and resulting in poor control over the heat of hydration. If the particle size is too large, the SAP may develop large pores after water loss, leading to reduced bonding strength and density in the early-strength tile adhesive. In the early-strength tile adhesive of this invention, the particle size of the SAP is controlled to be 180μm-420μm, preferably 220μm-380μm. Controlling the particle size of the SAP within this range not only achieves a suitable water loss rate and effectively controls the heat of hydration and shrinkage during hydration, but also allows the formation of a stable microporous structure within the space created by the SAP's shrinkage after water loss. This improves the tile adhesive's shock resistance and sound insulation capabilities, further preventing the impact of disturbances during transportation and hoisting of prefabricated buildings on the early-strength tile adhesive of this invention, and reducing delamination and cracking.

[0055] The early-strength tile adhesive of this invention also incorporates mineral admixtures, which enhance the durability and strength of the adhesive through filling and pozzolanic effects, reduce cracking, and improve the performance retention time of the early-strength tile adhesive along with superabsorbent resin. Furthermore, the mineral admixtures, made from clay minerals, possess excellent plasticity and viscosity. These not only improve the durability and strength of the early-strength tile adhesive but also increase its plasticity, thixotropy, adhesive strength, and adhesion, improving its workability, particularly during application and tile laying. This results in increased fluidity when subjected to shear force (during stirring) while maintaining relative stability at rest, allowing the tile to adhere stably to the substrate. The addition of clay mineral admixtures also reduces the impact of superabsorbent resin on the workability of the early-strength tile adhesive, preventing tile slippage. Meanwhile, the mineral admixtures made from clay minerals also possess excellent water retention and expansion effects. Their water retention properties, combined with highly absorbent resins, synergistically regulate moisture levels, further reducing drying shrinkage. Their expansion effect can also fill cracks that may result from shrinkage, improving the density and bonding strength of the early-strength tile adhesive of this invention. Furthermore, as clay minerals are natural materials, mineral admixtures made from clay minerals are also environmentally friendly during use.

[0056] Preferably, the superabsorbent polymer (SAP) includes at least one of sodium polyacrylate, polyacrylamide, polyvinyl alcohol-grafted acrylate, cellulose-grafted acrylate, and acrylic acid-acrylamide copolymer. The synthesis of these materials is relatively mature, allowing for accurate control of the SAP's water absorption rate and minimizing the risk of synthesis errors. Furthermore, since excessively high water absorption is not required, these materials are relatively inexpensive. In practical applications, the SAP used in the early-strength tile adhesive of this invention is not limited to the types mentioned above; other types of SAP can also be used, provided that the particle size and water absorption rate requirements are met, and the relevant processes are mature and can be stably supplied.

[0057] More preferably, the superabsorbent resin includes sodium polyacrylate, polyvinyl alcohol grafted acrylate, and acrylic acid-acrylamide copolymer.

[0058] Preferably, the cement includes at least one of P.Ⅱ.52.5, P.Ⅱ.42.5, P.Ⅱ.52.5R, P.Ⅱ.42.5R, PO42.5, and PO52.5. The cement particle size does not exceed 80 μm; the cement specific surface area is 350-450 m2 / kg.

[0059] It should be noted that the above selection of cement grade is based on the consideration of early strength, open time and other factors in normal operation of the early strength tile adhesive of the present invention. It does not mean that other grades or types of cement cannot be used for the early strength tile adhesive of the present invention. For example, when higher early strength and later durability are required, cements with higher strength and higher early strength, such as P.Ⅱ.62.5 and P.Ⅱ.62.5R, can be selected. However, this will result in a shorter open time for the early strength tile adhesive. The early strength tile adhesive should be used as soon as possible after mixing.

[0060] Preferably, the specific surface area of ​​the mineral admixture is 22-28 m². 2 / g. It is necessary to control the specific surface area of ​​the mineral admixtures to ensure their pozzolanic activity and water retention capacity, thereby improving the later strength and flowability of the early-strength tile adhesive of this invention.

[0061] Preferably, the mineral admixture includes fly ash, silica fume, ultrafine slag, and mineral admixtures made primarily from clay minerals.

[0062] More preferably, the mineral admixture is a mineral admixture made from clay minerals, preferably at least one of kaolin powder, metakaolin powder, bentonite powder, sepiolite powder, and illite powder. Kaolin powder, bentonite powder, sepiolite powder, and illite powder are all made from crushed and processed natural clay minerals. Metakaolin powder is made from kaolin powder after high-temperature calcination. Considering cost and applicability, the mineral admixture is preferably at least one of kaolin powder, metakaolin powder, and bentonite powder. If the prefabricated building modules need to be used in a relatively complex chemical environment, preferably, the mineral admixture is a compound of at least one of kaolin powder, metakaolin powder, and bentonite powder with at least one of sepiolite powder and illite powder, as sepiolite powder and illite powder have strong ion adsorption capacity.

[0063] Preferably, the graded aggregate includes at least one of river sand, lake sand, mountain sand, quartz sand, granite sand, basalt sand, and recycled sand. Quartz sand, granite sand, and basalt sand are preferred. Among these, quartz sand, granite sand, and basalt sand are all manufactured sands, whose particle size range is easily controlled and contain fewer impurities.

[0064] Preferably, the adhesive powder includes at least one of ethylene-vinyl acetate copolymer adhesive powder, acrylate adhesive powder, polyvinyl acetate adhesive powder, styrene-butadiene adhesive powder, polyvinyl alcohol adhesive powder, polyurethane adhesive powder, and starch ether adhesive powder. The adhesive powder is selected according to design requirements.

[0065] Preferably, the chopped fibers include polypropylene fibers, polyethylene fibers, polyvinyl alcohol fibers, and wood fibers.

[0066] More preferably, the chopped fibers are wood fibers. The wood fibers are 4-8 mm in length and no more than 40 μm in diameter. The good flexibility and dispersibility of wood fibers enable them to form a three-dimensional network structure within the tile adhesive, further enhancing the crack resistance and anti-slip properties of the early-strength tile adhesive of this invention, and reducing hollowness. Wood fibers also have a certain water absorption and retention capacity, which further enhances the durability and workability of the early-strength tile adhesive of this invention. However, the wood fibers should not be too long or too large in diameter, otherwise it will affect the flowability and plasticity of the early-strength tile adhesive of this invention. If the length is too short, its performance will be insufficient, leading to a decrease in the crack resistance and anti-slip properties of the early-strength tile adhesive of this invention.

[0067] Preferably, the early-strength agent is at least one of calcium formate, sodium formate, lithium nitrate, calcium nitrate, calcium sulfate, and sodium sulfate. Among them, organic early-strength agents, carbonate early-strength agents, and nitrate-based early-strength agents are preferred. Although sulfate early-strength agents can achieve the desired early-strength effect, they may have a certain impact on the water absorption rate and durability of the superabsorbent resin, and the dosage needs to be strictly controlled during use.

[0068] More preferably, the thickener is a cellulose-based thickener. Cellulose-based thickeners include at least one selected from hydroxypropyl methylcellulose, methylcellulose, hydroxymethylcellulose, and hydroxyethylcellulose; the viscosity of the cellulose-based thickener is 90,000-110,000 Pa·s, preferably 100,000 Pa·s. The thickener increases the viscosity of the early-strength tile adhesive of the present invention, improving its adhesion. Furthermore, the cellulose-based thickener can further cross-link with the adhesive powder and wood fibers, improving the crack resistance of the early-strength tile adhesive of the present invention.

[0069] This invention also provides a method for preparing early-strength tile adhesive, characterized by comprising the following steps:

[0070] S1: Prepare the corresponding raw materials according to the proportion of raw materials of the early-strength tile adhesive applicable to prefabricated buildings of the present invention, and mix the superabsorbent resin with 10%-20% water in the raw materials to obtain superabsorbent resin gel.

[0071] S2: Mix the early strength agent, thickener and the remaining 80%-90% water in the raw materials to obtain a wet material;

[0072] S3: Mix cement, mineral admixtures, graded aggregates, adhesive powder and wood fiber to obtain dry material;

[0073] S4: Mix and stir the superabsorbent resin gel, dry material and wet material to obtain early-strength tile adhesive.

[0074] In step S1, the superabsorbent polymer (SAP) is mixed with a certain amount of water beforehand, allowing the SAP to absorb water and transform from a solid state to a gel state. It is important to avoid directly mixing the dry SAP with dry or wet materials to prevent the SAP from competing with the cement for free water and thus reducing the early hydration rate of the early-strength tile adhesive. Once the SAP has completely absorbed the water it was mixed with, or has stopped absorbing water, a superabsorbent polymer gel is obtained. If there is any unabsorbed water, it is added to step S4 along with the superabsorbent polymer gel.

[0075] In step S2, mixing the accelerator, thickener, and water in advance helps to facilitate the rapid mixing of the accelerator, thickener, and dry material in subsequent processes.

[0076] In step S3, cement, mineral admixtures, graded aggregates, adhesive powder, and wood fiber are mixed and stirred to obtain dry material, which can reduce the time required for these materials to be fully mixed with wet materials and reduce the loss of open time of early-strength tile adhesive.

[0077] In step S4, the stirring speed should not be too high to prevent the superabsorbent resin gel from breaking down in large quantities, which would reduce its water absorption effect and prevent it from achieving the effect of water storage and retention.

[0078] Specifically, in step S2, when mixing the early strength agent, thickener and water, the stirring speed is 300-500 rpm and the stirring time is 1-3 min (min: minutes).

[0079] In step S3, when mixing cement, mineral admixtures, graded aggregates, adhesive powder and wood fiber, the mixing speed is 300-500 rpm (rpm: revolutions per minute) and the mixing time is 1-2 minutes.

[0080] In step S4, when mixing and stirring the superabsorbent resin gel, dry material and wet material, the stirring speed is 150-250 rpm and the stirring time is 2-4 min.

[0081] To better understand the above technical solutions, exemplary embodiments of the present invention will be described in more detail below. However, it should be understood that the present invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that the present invention can be understood more clearly and thoroughly, and that the scope of the present invention can be fully conveyed to those skilled in the art.

[0082] First, it's important to note that due to variations in production processes, chemical composition, particle size distribution, weight control standards, and testing conditions, even within the same batch of superabsorbent polymers (SAPs), the water absorption rate (which is the number of times the SAP can absorb its own weight in water) can fluctuate. For example, if a selected SAP can absorb 300 times its own weight in water (i.e., a water absorption rate of 300), the actual water absorption rate might fluctuate between 285 and 315, meaning there will be a certain positive or negative error, typically ±5% to ±10%. Redundancy control is necessary during use. Similarly, like the water absorption rate, the particle size of SAPs also exhibits a gradient distribution. While precise control is possible through secondary grading and sieving to select SAPs with accurate particle size and water absorption rate parameters, this significantly increases material and time costs and is only suitable for experimental environments. To ensure the accuracy of the description of the present invention, the particle size of the superabsorbent resin mentioned in the embodiments of the present invention is given as a particle size range, and the water absorption rate is given as the average value of the fluctuation range (i.e., before use, multiple random superabsorbent resin samples are taken, and after they are saturated with water, the average value of the water absorption rate of the multiple samples is calculated).

[0083] Example 1

[0084] This embodiment provides an early-strength ceramic tile adhesive suitable for prefabricated buildings. By weight, its raw materials include: 40 parts cement, 8 parts metakaolin powder, 70 parts quartz sand, 3 parts ethylene-vinyl acetate copolymer powder, 0.04 parts calcium formate, 0.01 parts hydroxypropyl methylcellulose, 0.05 parts sodium polyacrylate, 0.8 parts wood fiber, and 30 parts water.

[0085] The cement grade is P.Ⅱ52.5. In the quartz sand, the content of particles with a diameter of 0.020mm-0.080mm is 25wt%, the content of particles with a diameter of 0.080mm-0.170mm is 12wt%, the content of particles with a diameter of 0.170mm-0.800mm is 30wt%, and the content of particles with a diameter of 0.800mm-2.36mm is 33wt%.

[0086] Sodium polyacrylate can absorb 300 times its own weight in water; the particle size of superabsorbent resin is 220μm-380μm.

[0087] This embodiment also provides a method for preparing early-strength tile adhesive suitable for prefabricated buildings, including the following steps:

[0088] S1: Prepare the raw materials and mix sodium polyacrylate with 6 parts water to obtain sodium polyacrylate gel.

[0089] S2: Mix calcium formate, hydroxypropyl methylcellulose, and the remaining 24 parts of water to obtain a wet mixture. The mixing speed is 400 rpm and the mixing time is 2 minutes.

[0090] S3: Mix cement, metakaolin powder, quartz sand, ethylene-vinyl acetate copolymer powder, and wood fiber to obtain a dry mixture. The mixing speed is 400 rpm and the mixing time is 1 min.

[0091] S4: The sodium polyacrylate gel, dry material, and wet material are mixed and stirred to obtain the early-strength tile adhesive of the present invention. The stirring speed is 200 rpm, and the stirring time is 3 minutes.

[0092] The test results showed that the 1-day (d: day) tensile bond strength of the obtained early-strength tile adhesive was 0.609 MPa, the 3-day tensile bond strength was 1.215 MPa, the 3-day drying shrinkage rate was 0.014%, and the tile hollow rate after vibration simulation was 1.5%.

[0093] The tensile bond strength test standard for tile adhesive is conducted according to JC / T 547-2017 "Ceramic Tile Adhesives", and the drying shrinkage rate test standard is conducted according to GB / T 29417-2012 "Test Method for Drying Shrinkage Cracking Performance of Cement Mortar and Concrete".

[0094] Vibration simulation is conducted using an electric vibration table or a dedicated vibration testing machine, with a simulation time of 4-6 hours, including the following road condition simulation phases:

[0095] The first stage, highway (low-frequency vibration, using a random vibration table), accounts for 60% of the testing time. The testing conditions are: PSD (power spectral density) 0.01-0.03 g² / Hz. (g is the unit of gravitational acceleration; Hz is the unit of frequency.)

[0096] The second stage, ordinary highway (medium frequency vibration, using a random vibration table), accounts for 30% of the test time, and the test conditions are: PSD 0.03-0.06g2 / Hz.

[0097] The third stage, involving bumpy roads and hoisting (high-frequency impact, using a sinusoidal vibration table), accounts for 10% of the test time. The test conditions are: 2.5g@10Hz.

[0098] After vibration simulation, a hollow rate test is conducted. The hollow rate test is mainly conducted by gently tapping the four corners and center of the tile with a hollow hammer and listening to the sound to determine the location of the hollow. If there are two hollows in the four corners and the center, the tile is considered to be hollow. Then, the proportion of the area of ​​the hollow tiles to the total number of tiles is calculated to obtain the hollow rate.

[0099] Example 2

[0100] This embodiment provides an early-strength ceramic tile adhesive suitable for prefabricated buildings. The difference from Embodiment 1 is that, in this embodiment, the raw materials, by weight, include: 45 parts cement, 10 parts metakaolin, 80 parts quartz sand, 2 parts ethylene-vinyl acetate copolymer powder, 0.05 parts calcium formate, 0.02 parts hydroxypropyl methylcellulose, 0.07 parts sodium polyacrylate, 1 part wood fiber, and 35 parts water.

[0101] In the quartz sand, the content of particles with a diameter of 0.020mm-0.080mm is 27wt%, the content of particles with a diameter of 0.080mm-0.170mm is 11wt%, the content of particles with a diameter of 0.170mm-0.800mm is 27wt%, and the content of particles with a diameter of 0.800mm-2.36mm is 35wt%.

[0102] The early-strength tile adhesive tested showed a 1-day tensile bond strength of 0.692 MPa, a 3-day tensile bond strength of 1.191 MPa, a 3-day drying shrinkage rate of 0.014%, and a tile hollow rate of 1.4% after vibration simulation. The testing method was the same as in Example 1.

[0103] Example 3

[0104] This embodiment provides an early-strength tile adhesive suitable for prefabricated buildings. The difference from Embodiment 1 is that, in this embodiment, the raw materials, by weight, include: 30 parts cement, 6 parts metakaolin, 65 parts quartz sand, 2 parts ethylene-vinyl acetate copolymer powder, 0.05 parts calcium formate, 0.02 parts hydroxypropyl methylcellulose, 0.1 parts sodium polyacrylate, 1 part wood fiber, and 35 parts water.

[0105] In the quartz sand, the content of particles with a diameter of 0.020mm-0.080mm is 21wt%, the content of particles with a diameter of 0.080mm-0.170mm is 10wt%, the content of particles with a diameter of 0.170mm-0.800mm is 32wt%, and the content of particles with a diameter of 0.800mm-2.36mm is 37wt%.

[0106] The early-strength tile adhesive tested showed a 1-day tensile bond strength of 0.557 MPa, a 3-day tensile bond strength of 1.059 MPa, a 3-day drying shrinkage rate of 0.015%, and a tile hollow rate of 1.5% after vibration simulation. The testing method was the same as in Example 1.

[0107] Example 4

[0108] This embodiment provides an early-strength ceramic tile adhesive suitable for prefabricated buildings. The difference from Embodiment 2 is that, in this embodiment, by weight, the following components are present: 45 parts cement, 10 parts metakaolin powder, 70 parts quartz sand, 2 parts ethylene-vinyl acetate copolymer adhesive powder, 2 parts polyurethane adhesive powder, 0.01 parts lithium nitrate, 0.04 parts calcium formate, 0.02 parts hydroxypropyl methylcellulose, 0.07 parts sodium polyacrylate, 1 part wood fiber, and 40 parts water.

[0109] The early-strength tile adhesive tested showed a 1-day tensile bond strength of 0.736 MPa, a 3-day tensile bond strength of 1.341 MPa, a 3-day drying shrinkage rate of 0.014%, and a tile hollow rate of 1.2% after vibration simulation. The testing method was the same as in Example 1.

[0110] Example 5

[0111] This embodiment provides an early-strength tile adhesive suitable for prefabricated buildings. The difference from Embodiment 1 is that, in this embodiment, the raw materials, by weight, include: 40 parts cement, 8 parts kaolin powder, 70 parts quartz sand, 4 parts ethylene-vinyl acetate copolymer powder, 2 parts polyurethane powder, 0.08 parts calcium formate, 0.04 parts hydroxypropyl methylcellulose, 0.04 parts sodium polyacrylate, 0.05 parts acrylic acid-acrylamide copolymer, 1.5 parts wood fiber, and 55 parts water.

[0112] The early-strength tile adhesive tested showed a 1-day tensile bond strength of 0.887 MPa, a 3-day tensile bond strength of 1.396 MPa, a 3-day drying shrinkage rate of 0.015%, and a tile hollow rate of 1.4% after vibration simulation. The testing method was the same as in Example 1.

[0113] Example 6

[0114] This embodiment provides an early-strength tile adhesive suitable for prefabricated buildings. The difference from Embodiment 1 is that in this embodiment, sodium polyacrylate can absorb 250 times its own weight in water.

[0115] The early-strength tile adhesive tested showed a 1-day tensile bond strength of 0.624 MPa, a 3-day tensile bond strength of 1.307 MPa, a 3-day drying shrinkage rate of 0.015%, and a tile hollow rate of 1.6% after vibration simulation. The testing method was the same as in Example 1.

[0116] Example 7

[0117] This embodiment provides an early-strength tile adhesive suitable for prefabricated buildings. The difference from Embodiment 1 is that in this embodiment, sodium polyacrylate can absorb 350 times its own weight in water.

[0118] The early-strength tile adhesive tested showed a 1-day tensile bond strength of 0.603 MPa, a 3-day tensile bond strength of 1.139 MPa, a 3-day drying shrinkage rate of 0.013%, and a tile hollow rate of 1.4% after vibration simulation. The testing method was the same as in Example 1.

[0119] Example 8

[0120] This embodiment provides an early-strength tile adhesive suitable for prefabricated buildings. The difference from Embodiment 1 is that the particle size of sodium polyacrylate in this embodiment is 300-420μm.

[0121] The early-strength tile adhesive tested showed a 1-day tensile bond strength of 0.611 MPa, a 3-day tensile bond strength of 1.203 MPa, a 3-day drying shrinkage rate of 0.013%, and a tile hollow rate of 1.4% after vibration simulation. The testing method was the same as in Example 1.

[0122] Example 9

[0123] This embodiment provides an early-strength tile adhesive suitable for prefabricated buildings. The difference from Embodiment 1 is that the particle size of sodium polyacrylate in this embodiment is 180-300μm.

[0124] The early-strength tile adhesive tested showed a 1-day tensile bond strength of 0.627 MPa, a 3-day tensile bond strength of 1.243 MPa, a 3-day drying shrinkage rate of 0.015%, and a tile hollow rate of 1.6% after vibration simulation. The testing method was the same as in Example 1.

[0125] Example 10

[0126] This embodiment provides an early-strength tile adhesive suitable for prefabricated buildings. The difference from Embodiment 1 is that, in this embodiment, the raw materials, by weight, include: 40 parts cement, 8 parts ultrafine slag, 50 parts quartz sand, 20 parts granite sand, 2 parts ethylene-vinyl acetate copolymer powder, 2 parts polyurethane powder, 0.03 parts calcium formate, 0.03 parts lithium nitrate, 0.02 parts methylcellulose, 0.05 parts sodium polyacrylate, 0.05 parts polyacrylamide, 0.5 parts polypropylene fiber, 0.5 parts wood fiber, and 55 parts water.

[0127] The early-strength tile adhesive tested showed a 1-day tensile bond strength of 0.924 MPa, a 3-day tensile bond strength of 1.386 MPa, a 3-day drying shrinkage rate of 0.015%, and a tile hollow rate of 1.3% after vibration simulation. The testing method was the same as in Example 1.

[0128] Example 11

[0129] This embodiment provides an early-strength ceramic tile adhesive suitable for prefabricated buildings. The difference from Embodiment 1 is that the cement grade in this embodiment is P.Ⅱ.52.5R.

[0130] The early-strength tile adhesive tested showed a 1-day tensile bond strength of 1.424 MPa, a 3-day tensile bond strength of 2.337 MPa, a 3-day drying shrinkage rate of 0.016%, and a tile hollow rate of 0.9% after vibration simulation. The testing method was the same as in Example 1.

[0131] Example 12

[0132] This embodiment provides an early-strength tile adhesive suitable for prefabricated buildings. The difference from Embodiment 3 is that, in this embodiment, the raw materials, by weight, include: 25 parts cement, 8 parts kaolin, 55 parts quartz sand, 2 parts ethylene-vinyl acetate copolymer powder, 1 part polyurethane powder, 0.06 parts lithium nitrate, 0.03 parts calcium nitrate, 0.04 parts methylcellulose, 0.05 parts sodium polyacrylate, 0.05 parts polyacrylamide, 0.5 parts polypropylene fiber, 0.5 parts wood fiber, and 35 parts water.

[0133] The early-strength tile adhesive tested showed a 1-day tensile bond strength of 0.812 MPa, a 3-day tensile bond strength of 1.197 MPa, a 3-day drying shrinkage rate of 0.014%, and a tile hollow rate of 1.3% after vibration simulation. The testing method was the same as in Example 1.

[0134] Comparative Example 1

[0135] This embodiment provides an early-strength tile adhesive suitable for prefabricated buildings. The difference from Embodiment 1 is that sodium polyacrylate is not used in this embodiment.

[0136] The tested tile adhesive showed a 1-day tensile bond strength of 0.685 MPa, a 3-day tensile bond strength of 1.259 MPa, a 3-day drying shrinkage rate of 0.048%, and a tile hollow rate of 23% after vibration simulation. The test method was the same as in Example 1.

[0137] Comparative Example 2

[0138] This embodiment provides an early-strength tile adhesive suitable for prefabricated buildings. The difference from Embodiment 1 is that in this embodiment, the amount of sodium polyacrylate is 0.2 parts.

[0139] The tile adhesive cannot be formed and is unusable after mixing.

[0140] Comparative Example 3

[0141] This embodiment provides an early-strength tile adhesive suitable for prefabricated buildings. The difference from Embodiment 1 is that in this embodiment, the particle size of the superabsorbent resin is 480-580μm.

[0142] The early-strength tile adhesive tested showed a 1-day tensile bond strength of 0.615 MPa, a 3-day tensile bond strength of 1.105 MPa, a 3-day drying shrinkage rate of 0.012%, and a tile hollow rate of 15% after vibration simulation. The testing method was the same as in Example 1.

[0143] Comparative Example 4

[0144] This embodiment provides an early-strength tile adhesive suitable for prefabricated buildings. The difference from Embodiment 1 is that in this embodiment, the particle size of the superabsorbent resin is 50-150μm.

[0145] The early-strength tile adhesive tested showed a 1-day tensile bond strength of 0.726 MPa, a 3-day tensile bond strength of 1.473 MPa, a 3-day drying shrinkage rate of 0.031%, and a tile hollow rate of 14% after vibration simulation. The testing method was the same as in Example 1.

[0146] Comparative Example 5

[0147] This embodiment provides an early-strength tile adhesive suitable for prefabricated buildings. The difference from Embodiment 1 is that in this embodiment, sodium polyacrylate can absorb 50 times its own weight in water.

[0148] The early-strength tile adhesive tested showed a 1-day tensile bond strength of 0.642 MPa, a 3-day tensile bond strength of 1.315 MPa, a 3-day drying shrinkage rate of 0.037%, and a tile hollow rate of 18% after vibration simulation. The testing method was the same as in Example 1.

[0149] Comparative Example 6

[0150] This embodiment provides an early-strength tile adhesive suitable for prefabricated buildings. The difference from Embodiment 1 is that in this embodiment, ordinary aggregate is used instead of graded aggregate. In the ordinary aggregate, the mass fraction of particles with a particle size of 0.100mm-0.400mm is 92wt%, and the mass fraction of particles with a particle size of 0.010-0.015mm is 8wt%.

[0151] The tested tile adhesive showed a 1-day tensile bond strength of 0.563 MPa, a 3-day tensile bond strength of 0.786 MPa, a 3-day drying shrinkage rate of 0.035%, and a tile hollowness rate of 25% after vibration simulation. The test method was the same as in Example 1.

[0152] Based on the data from Example 1 and Comparative Example 1, it can be seen that the addition of superabsorbent resin can significantly improve the seismic resistance of tile adhesive and reduce the phenomenon of hollow tiles. Comparative Example 1, although using an accelerator, achieves a higher curing speed and early bond strength under its action, but because it does not use superabsorbent resin, its early hydration heat is higher, resulting in greater shrinkage and potentially bond failure, leading to a higher rate of hollow tiles.

[0153] Based on the data from Examples 1, 7, and Comparative Example 2, it can be observed that in Example 7, due to the increased water absorption rate of the superabsorbent resin, the early contact between cement and free water decreased, resulting in a slight decrease in early bond strength. However, its shrinkage control was better, leading to fewer potential cracks and a lower rate of hollow areas. In the Comparative Example, due to the excessive addition of superabsorbent resin, the superabsorbent resin competed with the cement for free water, rendering the tile adhesive unusable.

[0154] Based on the data from Examples 1-3 and Comparative Example 6, it can be found that the use of graded aggregates and early-strength agents in Examples 1-3 can improve the early strength of the early-strength tile adhesive of the present invention, ensure uniform stress distribution in the tile adhesive layer, and significantly reduce tile hollowing. Comparative Example 6, because it only uses two types of fine aggregates with smaller particle sizes and an early-strength agent, although it can achieve a certain early bond strength under the action of the early-strength agent, it cannot break through the strength development speed of a single material and cannot obtain higher early strength. Furthermore, due to the lack of aggregate gradation, the stress is uneven, resulting in a higher hollowing rate after vibration.

[0155] Based on the data from Examples 1, 7, and Comparative Example 2, it can be observed that in Example 7, due to the increased water absorption rate of the superabsorbent resin, the early contact between cement and free water decreased, resulting in a slight decrease in early bond strength. However, its shrinkage control was better, leading to fewer potential cracks and a lower rate of hollow areas. In the Comparative Example, due to the excessive addition of superabsorbent resin, the superabsorbent resin competed with the cement for free water, rendering the tile adhesive unusable.

[0156] Based on the data from Examples 1, 8, and Comparative Example 3, it can be observed that in Example 8, due to the larger particle size of the superabsorbent resin, the water loss rate is slower, resulting in slower bond strength development at 3 days. In Comparative Example 3, the excessively large particle size of the superabsorbent resin leads to a further decrease in bond strength at 3 days. Furthermore, the excessively large particle size may cause localized weakening of the bond at the contact points between the early-strength tile adhesive and the tile / substrate, further reducing bond strength, resulting in weak adhesion and a high rate of hollow areas after vibration.

[0157] Based on the data from Examples 1, 9, and Comparative Example 4, it can be observed that Example 9, due to the use of a smaller particle size superabsorbent resin, exhibits relatively poor control over early bond strength compared to Example 1. Bond strength develops more rapidly, and both shrinkage and void rates are increased. Comparative Example 4, due to the excessively small particle size of the superabsorbent resin, experiences excessively rapid water loss. While it achieves high early bond strength, it fails to control shrinkage and void rates.

[0158] Based on the data from Examples 1 and 6 and Comparative Example 5, it can be observed that in Example 6, due to the decreased water absorption rate of the superabsorbent resin, the amount of free water in contact with cement during the early stages of hydration increased, resulting in a slight increase in early bond strength. However, the ability to control cement shrinkage was slightly reduced, leading to an increased rate of voids. In Comparative Example 5, due to its excessively low water absorption rate, although the early bond strength was high, shrinkage could not be controlled, resulting in more cracks and a significantly higher rate of voids after vibration.

[0159] In summary, the early-strength tile adhesive of the present invention can solve the problems existing in the prior art where, after using cement-based tile adhesive to lay tiles in prefabricated building modules, the tiles are prone to hollowing, falling off, and displacement due to disturbance during transportation and hoisting.

[0160] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A fast setting tile adhesive suitable for use in fabricated construction, characterised in that, The raw materials of the early-strength ceramic tile adhesive include cement 20-50 parts by weight, mineral admixture 4-12 parts by weight, graded aggregate 50-95 parts by weight, powder 1-6 parts by weight, early-strength agent 0.01-0.1 parts by weight, thickening agent 0.01-0.05 parts by weight, superabsorbent resin 0.03-0.12 parts by weight, chopped fiber 0.3-2 parts by weight, and water 20-65 parts by weight; The particle size of the particles in the graded aggregate is between 2.36 mm and 0.020 mm; in the graded aggregate, the content of particles with a particle size greater than 0.080 mm is not more than 80%, the content of particles with a particle size greater than 0.170 mm is not less than 58%, and the content of particles with a particle size greater than 0.800 mm is not more than 38%; The superabsorbent resin can absorb 100-400 times its own weight of water; the particle size of the superabsorbent resin is 180 μm-420 μm; The early-strength agent includes at least one of nitrate early-strength agent, carbonate early-strength agent, organic early-strength agent, and sulfate early-strength agent.

2. A fast-setting tile adhesive for use in fabricated construction as claimed in claim 1, wherein, The raw materials of the early-strength ceramic tile adhesive include cement 30-45 parts by weight, mineral admixture 6-10 parts by weight, graded aggregate 60-80 parts by weight, powder 2-4 parts by weight, early-strength agent 0.02-0.06 parts by weight, thickening agent 0.01-0.02 parts by weight, superabsorbent resin 0.05-0.1 parts by weight, chopped fiber 0.5-1 parts by weight, and water 25-55 parts by weight; The mineral admixture is a mineral admixture made of clay minerals; in the graded aggregate, the content of particles with a particle size of 0.020 mm-0.080 mm is 20-28 wt%, the content of particles with a particle size of 0.080 mm-0.170 mm is 10-14 wt%, the content of particles with a particle size of 0.170 mm-0.800 mm is 25-35 wt%, and the content of particles with a particle size of 0.800 mm-2.36 mm is 30-38 wt%; the superabsorbent resin can absorb 250-350 times its own weight of water; the particle size of the superabsorbent resin is 220 μm-380 μm; the early-strength agent includes nitrate early-strength agent, carbonate early-strength agent, and organic early-strength agent; the cement is Portland cement and / or ordinary Portland cement.

3. A fast-setting tile adhesive for use in fabricated construction as claimed in claim 2, wherein, The superabsorbent resin includes at least one of sodium polyacrylate, polyacrylamide, polyvinyl alcohol grafted acrylate, cellulose grafted acrylate, and acrylamide copolymer.

4. A fast-setting tile adhesive for use in fabricated construction as claimed in claim 2, wherein, The cement is at least one of P.Ⅱ.52.5, P.Ⅱ.42.5, P.Ⅱ.52.5R, P.Ⅱ.42.5R, P.O.42.5, and P.O.52.5; the particle size of the cement is not more than 80 μm; the specific surface area of the cement is 350-450 m2 / kg.

5. A fast-setting tile adhesive for use in fabricated construction as claimed in claim 2, wherein, The mineral admixture has a specific surface area of 22-28 m 2 / g; the mineral admixture includes at least one of kaolin powder, metakaolin powder, bentonite powder, sepiolite powder, and illite powder.

6. A fast setting tile adhesive suitable for use in fabricated construction as claimed in claim 2, wherein, The graded aggregate includes at least one of river sand, lake sand, mountain sand, quartz sand, granite sand, basalt sand, and recycled sand.

7. A fast setting tile adhesive suitable for use in fabricated construction as claimed in claim 2, wherein, The powder includes at least one of ethylene-vinyl acetate copolymer powder, acrylate powder, polyvinyl acetate powder, butylphenyl powder, polyvinyl alcohol powder, polyurethane powder, and starch ether powder.

8. A fast setting tile adhesive suitable for use in fabricated construction as claimed in claim 2, wherein, The early strength agent includes at least one of calcium formate, lithium carbonate, lithium nitrate and calcium nitrate.

9. A fast setting tile adhesive suitable for use in fabricated construction as claimed in claim 2, wherein, The thickening agent is a cellulose thickening agent; the cellulose thickening agent includes at least one of hydroxypropyl methyl cellulose, methyl cellulose, hydroxymethyl cellulose, hydroxyethyl cellulose; the viscosity of the cellulose thickening agent is 90000-110000 Pa·s; the short-cut fiber is a wood fiber; the length of the wood fiber is 4-8 mm; the diameter of the wood fiber is not more than 40 μm.

10. A method for preparing early strength tile adhesive suitable for use in fabricated construction, characterized in that, The method comprises the following steps: S1: preparing raw materials according to the proportions of the raw materials of the early-strength ceramic tile glue for fabricated buildings according to any one of claims 1 to 9, and mixing the superabsorbent resin with 10%-20% water to obtain a superabsorbent resin gel; S2: mixing and stirring the early-strength agent, the thickening agent and the remaining 80%-90% water to obtain wet materials; S3: mixing and stirring the cement, the mineral admixture, the graded aggregate, the glue powder and the short-cut fiber to obtain dry materials; S4: mixing and stirring the superabsorbent resin gel, the dry materials and the wet materials to obtain the early-strength ceramic tile glue for fabricated buildings.