Self-impregnating high-durability polymer concrete and preparation process thereof

Abstract

The invention discloses self-impregnating high-durability polymer concrete and a preparation process thereof, and belongs to the technical field of building materials. The concrete provided by the invention is prepared from the following raw materials in parts by weight: cement, fine aggregate, coarse aggregate, a mineral admixture, water, a polymer emulsion, a high-efficiency water reducing agent, gelatin-Arabic gum complex coacervation microcapsules, super absorbent resin, a defoaming agent and a coalescing agent. The preparation method comprises the following steps: pre-swelling the gelatin-Arabic gum complex coacervation microcapsule and the super absorbent resin to prepare a premixed solution; stirring the cement, the fine aggregate, the coarse aggregate and the mineral admixture to obtain a dry mixture; adding the remaining raw materials into the dry mixture, and stirring to form slurry; and adding the premixed liquid into the slurry, continuously stirring to obtain a concrete mixture, pouring and molding, and naturally curing to obtain the self-impregnated high-durability polymer concrete. The concrete prepared by the invention can synchronously improve mechanical properties, durability and self-curing ability.

Description

Technical Field

[0001] This application belongs to the field of building materials technology, specifically relating to a self-impregnating high-durability polymer concrete and its preparation process. Background Technology

[0002] As the most widely used building material, concrete's performance directly affects the service life and safety of infrastructure. Under harsh service environments, traditional silicate cement-based concrete is prone to strength degradation, steel corrosion, and structural failure due to problems such as interconnected internal pores, microcrack propagation, and insufficient hydration. Existing technologies typically improve the density, impermeability, and toughness of concrete by incorporating polymer components, utilizing their film-forming properties to fill pores.

[0003] However, current polymer concrete still has significant shortcomings: conventional polymer emulsions are prone to demulsification or phase separation in highly alkaline cement paste, affecting the stability of the system; although polymers can seal pores, they cannot solve the problem of early hydration water shortage, making it difficult to avoid internal micro-defects; in addition, most organic polymers are prone to aging and degradation under ultraviolet light, high temperature or chemical erosion environments, resulting in poor durability.

[0004] Therefore, there is an urgent need to develop a self-impregnating high-durability polymer concrete that can simultaneously improve mechanical properties, durability, and self-curing ability. Summary of the Invention

[0005] In view of this, this application provides a self-impregnating high-durability polymer concrete and its preparation process. The concrete provided by this application can simultaneously improve mechanical properties, durability, and self-curing ability.

[0006] In a first aspect, this application provides a self-impregnating high-durability polymer concrete, which, by weight, comprises: 400-600 parts cement, 700-1000 parts fine aggregate, 1000-1300 parts coarse aggregate, 80-240 parts mineral admixture, 110-190 parts water, 40-120 parts polymer emulsion, 4-9 parts high-efficiency water-reducing agent, 2-6 parts gelatin-gum arabic complex coagulated microcapsules, 0.8-3 parts superabsorbent resin, 0.2-0.8 parts defoamer, and 1-4 parts film-forming aid.

[0007] By employing the above-mentioned technical solutions, this application utilizes a combination of multiple raw materials to enable concrete to simultaneously achieve excellent mechanical properties, long-term durability, and self-curing capabilities. In this application, superabsorbent polymer (SAP) serves as the core of internal curing, slowly releasing stored moisture during the early hydration stage of concrete. This effectively compensates for the "self-drying" loss in low water-cement ratio systems, significantly inhibiting self-shrinkage and microcrack formation, thus ensuring full hydration and the formation of a dense structure. Simultaneously, gelatin-gum arabic composite microcapsules are uniformly dispersed in the matrix. When external loads or environmental factors induce microcracks, the capsules rupture, releasing the core material and activating a secondary hydration reaction at the crack site, achieving strength recovery and forming a dual protective mechanism. Furthermore, the polymer emulsion forms a continuous, flexible, and alkali-resistant organic-inorganic composite network in the cement paste, not only filling pores and reducing permeation but also significantly enhancing bond strength and toughness. In this application, the introduction of film-forming aids ensures efficient film formation of the polymer at room temperature, while defoamers eliminate harmful bubbles introduced during stirring, further improving density. The two work synergistically to ensure the effective functioning of the polymer and avoid performance degradation caused by demulsification, porosity, or incomplete film formation. Therefore, this application achieves simultaneous improvement in mechanical properties, durability, and self-maintenance capabilities through the compounding of the above raw materials.

[0008] Optionally, the cement is P·II 52.5R silicate cement.

[0009] By adopting the above technical solution, P·II 52.5R silicate cement has a low alkali content, effectively reducing the risk of adverse chemical reactions with polymer emulsions, superabsorbent resins, and gelatin-gum arabic complex microcapsules, thus ensuring the stability and long-term compatibility of the system. Furthermore, its high purity and high reactivity facilitate full hydration under low water-cement ratio conditions, forming a denser microstructure with mineral admixtures, further enhancing impermeability and durability.

[0010] Optionally, the fine aggregate is manufactured sand with a fineness modulus of 2.3 to 2.8; the coarse aggregate is crushed stone with a continuous gradation of 5 mm to 20 mm.

[0011] By adopting the above technical solution, the coarse and fine aggregate combination of this application can significantly optimize the particle bulk density and interfacial structure of concrete. The manufactured sand particles have sharp edges and rough surfaces, which is beneficial to enhancing the mechanical strength of the polymer-cement paste. The continuously graded crushed stone effectively reduces the porosity between coarse aggregates, reduces the amount of paste required, and improves volume stability. The two work together to form a dense skeleton, which not only reduces the risk of shrinkage cracking, but also provides a uniformly distributed matrix environment for superabsorbent resin and microcapsules, thereby better exerting the self-curing and self-healing functions and improving the overall mechanical properties, impermeability, and durability of concrete.

[0012] Optionally, the mineral admixture includes at least one of silica fume, metakaolin, fly ash, blast furnace slag powder, and limestone powder.

[0013] By adopting the above technical solutions, the multiple mineral admixtures of this application can construct multi-scale particle gradation, optimize the rheology and microstructure of the paste, reduce cement usage, inhibit autogenous shrinkage, and provide a more stable and dense matrix environment for polymer film formation, superabsorbent resin internal curing, and microcapsule repair, thereby further improving the mechanical properties, durability, and self-curing ability of concrete.

[0014] Optionally, the mineral admixture is silica fume, fly ash and blast furnace slag powder, and the weight ratio of silica fume, fly ash and blast furnace slag powder is 1:(1.5~3):(1~3).

[0015] By adopting the above technical solution, in this mix, silica fume provides nanoscale filler and high early-age activity, significantly improving density and impermeability; fly ash improves workability, reduces heat of hydration, and enhances long-term durability; blast furnace slag powder further strengthens resistance to chloride ion penetration and sulfate attack, making it particularly suitable for harsh environments. The combined addition of these three components in the above proportions avoids the problems of high water demand and autogenous shrinkage caused by silica fume alone, while also compensating for the insufficient early-age strength of fly ash or blast furnace slag powder, further improving the mechanical properties, durability, and self-curing ability of concrete.

[0016] Optionally, the average particle size of the silica fume is 0.1~0.3μm; the average particle size of the fly ash is 10~30μm; and the average particle size of the blast furnace slag powder is 8~20μm.

[0017] By adopting the above technical solution, the particle size gradients of the three components are matched, and they work together to achieve close packing, which greatly reduces capillary pores and interconnected pores, improves the density and volume stability of concrete, and further enhances the mechanical properties, durability and self-curing ability of concrete.

[0018] Optionally, the polymer emulsion includes at least one of acrylate emulsion, epoxy-modified acrylate emulsion, ethylene-vinyl acetate copolymer emulsion, or silicone-acrylic composite emulsion.

[0019] By adopting the above technical solutions, the polymer emulsions of this application all exhibit excellent adaptability to highly alkaline environments, and can form a continuous, dense, and flexible organic-inorganic composite network in cement paste. Furthermore, various emulsions can be used alone or in combination to adapt to different service environment requirements. Without demulsification or stratification, they effectively fill pores and bridge microcracks, and synergistically enhance the mechanical properties and long-term durability of concrete by working with components such as superabsorbent resin and microcapsules.

[0020] Optionally, the solid content of the polymer emulsion is 50% to 65%.

[0021] By adopting the above technical solution, this range can effectively control the introduction of additional moisture while ensuring a high effective polymer content. Furthermore, this solids content range does not interfere with the swelling-water release behavior of the superabsorbent resin, which is beneficial for maintaining self-curing efficiency.

[0022] Optionally, the defoamer is selected from polyether-modified silicone oil or mineral oil defoamers.

[0023] By adopting the above technical solution, the defoamer of this application can effectively eliminate harmful air bubbles introduced during the mixing process, while taking into account the compatibility with polymer emulsion and cement matrix. Both can effectively reduce the porosity of hardened concrete, improve density and impermeability, and at the same time, do not damage the continuity of polymer film formation, thereby synergistically enhancing the mechanical properties and long-term durability of concrete.

[0024] Optionally, the film-forming aid includes at least one of acetylated tributyl citrate, 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, and dipropylene glycol methyl ether.

[0025] By adopting the above technical solutions, the film-forming aid of this application can effectively ensure that the polymer emulsion forms a continuous, dense and flexible organic film under normal temperature and low humidity conditions. All three are compatible with the high-alkali cement environment and do not interfere with the water release of superabsorbent resin or the stability of microcapsules, thereby synergistically enhancing the long-term durability of concrete and supporting the effective performance of self-curing and self-repair functions.

[0026] Optionally, the weight ratio of the superabsorbent resin to the gelatin-gum arabic complex microcapsules is 1:2~6.

[0027] By adopting the above technical solution, superabsorbent polymer (SAP) releases moisture in the early stage, compensating for self-drying, promoting full hydration, and inhibiting the initiation of microcracks. Simultaneously, the released water provides the necessary reaction medium for the core material to activate secondary hydration after the microcapsules rupture, significantly improving repair efficiency. Furthermore, the microcapsules are more easily and effectively sealed in the moist microenvironment created by SAP, forming a dense repair product. The formulation of this application avoids both insufficient microcapsules leading to inadequate repair capacity and excessive microcapsules causing interface weakening or cost waste, enabling the superabsorbent polymer and gelatin-gum arabic composite microcapsules to synergistically improve the mechanical properties, long-term durability, and self-curing ability of concrete.

[0028] Optionally, the gelatin-gum arabic complex microcapsules are prepared by the following steps: Step 1: Mix choline chloride and ethylene glycol in a 1:2 molar ratio, add light mineral oil, and form the core material; Step 2: Add the core material to the gelatin aqueous solution and shear emulsify it at 40℃~50℃ and 5000rpm~8000rpm for 15min~25min to obtain an O / W emulsion; Step 3: Add gum arabic aqueous solution to the O / W emulsion, adjust the pH to 4.0~4.8, and react at 35℃~45℃ for 1h~3h; Step 4: Cool to 5℃~10℃, let stand and solidify for 2h~4h, then add 0.5%~1.0% genipin solution, adjust pH to 9~10, crosslink for 0.5h~2h, wash and dry to obtain the gelatin-gum arabic composite microcapsules; the core material accounts for 70%~80% of the total mass of the microcapsules.

[0029] By adopting the above technical solution, the preparation method of gelatin-gum arabic composite microcapsules of this application uses choline chloride / ethylene glycol as the core material, which has both hydration activation and internal curing functions. The addition of light mineral oil improves its hydrophobicity and effectively inhibits premature leakage in high-alkali cement paste. Specific process parameters can ensure the formation of microcapsules with uniform particle size and dense membrane, which can be stably stored in concrete. The core material released after cracking can activate secondary hydration, significantly improving the mechanical properties and durability of concrete.

[0030] Optionally, in step one, the light mineral oil accounts for 5% to 10% of the total mass of the core material.

[0031] By adopting the above technical solution, this application controls the proportion of light mineral oil. On the one hand, as a hydrophobic carrier, light mineral oil can effectively reduce the interfacial tension between choline chloride / ethylene glycol and the aqueous phase, significantly improve emulsion stability, and promote the formation of O / W (oil-in-water) emulsions with uniform particle size. On the other hand, its low volatility and good compatibility can reduce leakage of the core material during storage and mixing, and improve the encapsulation rate and long-term stability under alkaline conditions. This approach can both play a role in co-emulsification and slow release without excessively diluting the active core material or introducing too much organic phase, thus weakening the mechanical properties of concrete.

[0032] Optionally, in step two, the mass concentration of the gelatin aqueous solution is 5% to 10%; in step three, the mass concentration of the gum arabic aqueous solution is 5% to 10%; and the mass ratio of the gelatin to the gum arabic is 1:(0.8 to 1.2).

[0033] By adopting the above technical solution, the appropriate solution concentration ensures a sufficient supply of wall material while avoiding excessive viscosity, emulsification difficulties, or agglomeration caused by excessive concentration. The mass ratio of gelatin to gum arabic is conducive to the formation of a dense and continuous composite wall membrane. This wall membrane not only has high mechanical strength and high encapsulation rate, but also effectively prevents the core material from leaking prematurely in a high-alkali cement environment. At the same time, it reliably ruptures and releases active substances when cracks occur, providing a reliable carrier guarantee for the self-repair and self-curing functions of concrete.

[0034] Secondly, this application provides a preparation process for the aforementioned self-impregnating high-durability polymer concrete, comprising the following steps: Step S1: Disperse the gelatin-gum arabic complex coagulated microcapsules and the superabsorbent resin in a portion of water and allow them to swell at room temperature for 5 to 15 minutes to obtain a premixed solution; Step S2: Mix the cement, fine aggregate, coarse aggregate, and mineral admixture for 1 to 2 minutes to obtain a dry mix; Step S3: Add the high-efficiency water-reducing agent, defoamer, film-forming aid and remaining water to the dry mixture, then add the polymer emulsion and stir for 2 min to 3 min to form a slurry; Step S4: Add the premixed liquid to the slurry and continue stirring for 2 to 4 minutes to obtain concrete mix. After pouring and molding, cure naturally at room temperature to obtain self-impregnating high-durability polymer concrete.

[0035] By adopting the above technical solution, the self-impregnating high-durability polymer concrete preparation process of this application ensures the uniform mixing of each functional component and protects the structural integrity of the internal curing and self-healing components, preventing them from failing or breaking during vigorous mixing, thereby effectively improving the mechanical properties, durability and self-curing ability of concrete.

[0036] In summary, the present invention has at least one of the following beneficial technical effects: 1. This application uses a combination of multiple raw materials to enable concrete to simultaneously achieve excellent mechanical properties, long-term durability, and self-curing ability.

[0037] 2. In this application, superabsorbent polymer (SAP) inhibits the formation of self-shrinkage and microcracks. When microcracks are induced by external loads or environmental factors, the gelatin-gum arabic composite microcapsules release the core material and activate the secondary hydration reaction at the cracks to achieve strength recovery. The two form a dual protection mechanism and synergistically improve the self-curing ability of concrete.

[0038] 3. The self-impregnating high-durability polymer concrete preparation process of this application ensures uniform mixing of various functional components and protects the structural integrity of internal curing and self-healing components, preventing them from failing or breaking during vigorous mixing, thereby effectively improving the mechanical properties, durability and self-curing ability of concrete. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0040] The inventors of this application discovered in their research on polymer concrete that conventional polymer emulsions are not stable enough in highly alkaline cement pastes, and are prone to demulsification or phase separation, leading to a decline in material homogeneity and long-term performance. Although polymers can fill pores and improve density to a certain extent, they cannot alleviate the self-drying and micro-crack problems caused by early hydration water shortage in concrete, making it difficult to fundamentally eliminate internal structural defects. In addition, most organic polymers are prone to aging, embrittlement, or degradation when exposed to harsh environments such as ultraviolet rays, high temperatures, or chemical erosion for a long time, thereby weakening the durability and service life of concrete.

[0041] To address the aforementioned problems, this application proposes a self-impregnating high-durability polymer concrete, which, by weight, comprises: 400-600 parts cement, 700-1000 parts fine aggregate, 1000-1300 parts coarse aggregate, 80-240 parts mineral admixture, 110-190 parts water, 40-120 parts polymer emulsion, 4-9 parts high-efficiency water-reducing agent, 2-6 parts gelatin-gum arabic complex coagulated microcapsules, 0.8-3 parts superabsorbent resin, 0.2-0.8 parts defoamer, and 1-4 parts film-forming aid.

[0042] This application also proposes a preparation process for the above-mentioned self-impregnating high-durability polymer concrete, including the following steps: Step S1: Disperse the gelatin-gum arabic complex coagulated microcapsules and the superabsorbent resin in a portion of water and allow them to swell at room temperature for 5 to 15 minutes to obtain a premixed solution; Step S2: Mix the cement, fine aggregate, coarse aggregate, and mineral admixture for 1 to 2 minutes to obtain a dry mix; Step S3: Add the high-efficiency water-reducing agent, defoamer, film-forming aid and remaining water to the dry mixture, then add the polymer emulsion and stir for 2 min to 3 min to form a slurry; Step S4: Add the premixed liquid to the slurry and continue stirring for 2 to 4 minutes to obtain concrete mix. After pouring and molding, cure naturally at room temperature to obtain self-impregnating high-durability polymer concrete.

[0043] The solution of this application will be described below with reference to the following specific embodiments. Unless otherwise specified, the raw materials used in the following embodiments are all from commercially available products, and the devices or equipment used are all purchased from conventional market sales channels. Specific Implementation

[0044] The gelatin-gum arabic coagulated microcapsules used in Examples 1-3 were prepared using the following steps: Step 1: Mix choline chloride and ethylene glycol at a molar ratio of 1:2, add light mineral oil to form the core material; the light mineral oil accounts for 10% of the total mass of the core material; Step 2: Add the core material to a gelatin aqueous solution and shear emulsify at 45°C and 6000 rpm for 20 minutes to obtain an O / W emulsion; the mass concentration of the gelatin aqueous solution is 8%. Step 3: Add an aqueous solution of gum arabic to the O / W emulsion, adjust the pH to 4.5, and react at 40°C for 2 hours; the mass concentration of the aqueous solution of gum arabic is 8%; the mass ratio of gelatin to gum arabic is 1:1.

[0045] Step 4: Cool to 10℃, let stand and solidify for 3 hours, then add 1.0% genipin solution, adjust pH to 9.5, crosslink for 1 hour, wash and dry to obtain the gelatin-gum arabic composite microcapsules; the core material accounts for 80% of the total mass of the microcapsules.

[0046] Examples 1-3 Example 1

[0047] This embodiment provides a self-impregnating high-durability polymer concrete, which, by weight, comprises: 600 parts cement, 700 parts fine aggregate, 1300 parts coarse aggregate, 80 parts mineral admixture, 110 parts water, 120 parts polymer emulsion, 4 parts high-efficiency water-reducing agent, 2 parts gelatin-gum arabic complex coagulating microcapsules, 0.8 parts superabsorbent resin, 0.2 parts defoamer, and 1 part film-forming aid. The cement is P·II 52.5R Portland cement; the fine aggregate is manufactured sand with a fineness modulus of 2.5; and the coarse aggregate is crushed stone with a continuous gradation of 5mm to 20mm. The mineral admixtures consist of silica fume, fly ash, and blast furnace slag powder in a weight ratio of 1:1.5:1; the average particle size of the silica fume is 0.2 μm; the average particle size of the fly ash is 20 μm; and the average particle size of the blast furnace slag powder is 15 μm. The polymer emulsion is an ethylene-vinyl acetate copolymer emulsion with a solid content of 60%; the high-efficiency water-reducing agent is a polycarboxylate water-reducing agent; the defoamer is a polyether-modified silicone oil; and the film-forming aid is dipropylene glycol methyl ether. The preparation method includes the following steps: Step S1: Disperse the gelatin-gum arabic complex microcapsules and superabsorbent resin in a portion of water and allow them to swell at room temperature for 5 minutes to obtain a premixed solution. Step S2: Mix cement, fine aggregate, coarse aggregate, and mineral admixture for 1 minute to obtain dry mix; Step S3: Add high-efficiency water-reducing agent, defoamer, film-forming aid and remaining water to the dry mixture, then add polymer emulsion and stir for 2 minutes to form a slurry; Step S4: Add the premixed liquid to the slurry and continue stirring for 2 minutes to obtain the concrete mix. After pouring and molding, allow it to cure naturally at room temperature to obtain self-impregnated high-durability polymer concrete. Example 2

[0048] This embodiment provides a self-impregnating high-durability polymer concrete, which, by weight, comprises: 500 parts cement, 850 parts fine aggregate, 1150 parts coarse aggregate, 160 parts mineral admixture, 150 parts water, 80 parts polymer emulsion, 6 parts high-efficiency water-reducing agent, 4 parts gelatin-gum arabic complex coagulating microcapsules, 2 parts superabsorbent resin, 0.5 parts defoamer, and 2.5 parts film-forming aid. The cement is P·II 52.5R Portland cement; the fine aggregate is manufactured sand with a fineness modulus of 2.5; and the coarse aggregate is crushed stone with a continuous gradation of 5mm to 20mm. The mineral admixtures consist of silica fume, fly ash, and blast furnace slag powder in a weight ratio of 1:1.5:1; the average particle size of the silica fume is 0.2 μm; the average particle size of the fly ash is 20 μm; and the average particle size of the blast furnace slag powder is 15 μm. The polymer emulsion is an ethylene-vinyl acetate copolymer emulsion with a solid content of 60%; the high-efficiency water-reducing agent is a polycarboxylate water-reducing agent; the defoamer is a polyether-modified silicone oil; and the film-forming aid is dipropylene glycol methyl ether. The preparation method includes the following steps: Step S1: Disperse the gelatin-gum arabic complex microcapsules and superabsorbent resin in a portion of water and allow them to swell at room temperature for 10 minutes to obtain a premixed solution; Step S2: Mix cement, fine aggregate, coarse aggregate, and mineral admixture for 2 minutes to obtain dry mix; Step S3: Add high-efficiency water-reducing agent, defoamer, film-forming aid and remaining water to the dry mixture, then add polymer emulsion and stir for 3 minutes to form a slurry; Step S4: Add the premixed liquid to the slurry and continue stirring for 3 minutes to obtain the concrete mix. After pouring and molding, allow it to cure naturally at room temperature to obtain self-impregnated high-durability polymer concrete. Example 3

[0049] This embodiment provides a self-impregnating high-durability polymer concrete, which, by weight, comprises: 400 parts cement, 1000 parts fine aggregate, 1000 parts coarse aggregate, 240 parts mineral admixture, 190 parts water, 40 parts polymer emulsion, 9 parts high-efficiency water-reducing agent, 6 parts gelatin-gum arabic complex coagulating microcapsules, 3 parts superabsorbent resin, 0.8 parts defoamer, and 4 parts film-forming aid. The cement is P·II 52.5R Portland cement; the fine aggregate is manufactured sand with a fineness modulus of 2.5; and the coarse aggregate is crushed stone with a continuous gradation of 5mm to 20mm. The mineral admixtures consist of silica fume, fly ash, and blast furnace slag powder in a weight ratio of 1:1.5:1; the average particle size of the silica fume is 0.2 μm; the average particle size of the fly ash is 20 μm; and the average particle size of the blast furnace slag powder is 15 μm. The polymer emulsion is an ethylene-vinyl acetate copolymer emulsion with a solid content of 60%; the high-efficiency water-reducing agent is a polycarboxylate water-reducing agent; the defoamer is a polyether-modified silicone oil; and the film-forming aid is dipropylene glycol methyl ether. The preparation method includes the following steps: Step S1: Disperse the gelatin-gum arabic complex microcapsules and superabsorbent resin in a portion of water and allow them to swell at room temperature for 15 minutes to obtain a premixed solution. Step S2: Mix cement, fine aggregate, coarse aggregate, and mineral admixture for 2 minutes to obtain dry mix; Step S3: Add high-efficiency water-reducing agent, defoamer, film-forming aid and remaining water to the dry mixture, then add polymer emulsion and stir for 3 minutes to form a slurry; Step S4: Add the premixed liquid to the slurry and continue stirring for 4 minutes to obtain the concrete mix. After pouring and molding, allow it to cure naturally at room temperature to obtain self-impregnated high-durability polymer concrete.

[0050] Comparative Examples 1-3 Comparative Example 1 The difference between Comparative Example 1 and Example 2 is that in Comparative Example 1, two parts of superabsorbent resin were replaced with an equal amount of gelatin-gum arabic complex microcapsules.

[0051] Comparative Example 2 The difference between Comparative Example 2 and Example 2 is that in Comparative Example 2, 4 parts of gelatin-gum arabic coagulated microcapsules were replaced with an equal amount of superabsorbent resin.

[0052] Comparative Example 3 The difference between Comparative Example 3 and Example 2 is that Comparative Example 3 did not contain superabsorbent resin and gelatin-gum arabic complex microcapsules.

[0053] Experimental testing Testing items and testing methods Mechanical properties: The compressive strength of the concrete at 7 days and 28 days is tested according to the compressive strength test method in GB / T 50081-2019 "Standard for Test Methods of Physical and Mechanical Properties of Concrete", thereby reflecting the mechanical properties of the concrete.

[0054] Durability: According to the stepwise pressurization method in the water permeability test of GB / T 50082-2024 "Standard for Test Methods of Long-term Performance and Durability of Concrete", the prepared concrete is cured for 28 days and the permeability grade is tested. The higher the permeability grade, the better the durability of the concrete.

[0055] Self-curing performance: According to the non-contact method of shrinkage test in GB / T 50082-2024 "Standard for Test Methods of Long-term Performance and Durability of Concrete", the 7-day autogenous shrinkage strain of concrete prepared in the example (with SAP) and the blank group (without SAP) was detected, and the autogenous shrinkage inhibition rate was recorded and calculated. The higher the autogenous shrinkage inhibition rate, the better the self-curing performance of the concrete. Blank group: Contains no superabsorbent polymer (SAP), other components are the same as the application scheme; Self-shrinkage inhibition rate = (1 - self-shrinkage strain of SAP-admixed concrete / self-shrinkage strain of blank concrete without SAP) × 100%.

[0056] The concrete prepared in Examples 1-3 and Comparative Examples 1-3 were tested for compressive strength, impermeability grade and autogenous shrinkage inhibition rate. The test results are shown in Table 1.

[0057] Table 1

[0058] As can be seen from the test results in Table 1, the concrete prepared in Examples 1 to 3 has high compressive strength and impermeability grade, good mechanical properties and durability, high self-shrinkage inhibition rate, and excellent self-curing ability.

[0059] In Comparative Example 1, replacing the superabsorbent resin with an equal amount of gelatin-gum arabic composite microcapsules resulted in a decrease in the compressive strength and durability of the concrete, as well as a significant reduction in its self-curing ability.

[0060] In Comparative Example 2, replacing the gelatin-gum arabic composite microcapsules with an equal amount of superabsorbent resin resulted in a decrease in the compressive strength and durability of the concrete.

[0061] Comparative Example 3, without the addition of superabsorbent resin and gelatin-gum arabic composite microcapsules, resulted in concrete with reduced compressive strength and durability, and poor self-curing ability.

[0062] Examples 4-13 Example 4

[0063] The difference between Example 4 and Example 2 is that in Example 4, the fineness modulus of the manufactured sand is 2.3. Example 5

[0064] The difference between Example 5 and Example 2 is that in Example 5, the fineness modulus of the manufactured sand is 2.8. Example 6

[0065] The difference between Example 6 and Example 2 is that in Example 6, the weight ratio of silica fume, fly ash and blast furnace slag powder is 1:2.2:2. Example 7

[0066] The difference between Example 7 and Example 2 is that in Example 7, the weight ratio of silica fume, fly ash and blast furnace slag powder is 1:3:3. Example 8

[0067] The difference between Example 8 and Example 6 is that in Example 8, the mineral admixture is fly ash and blast furnace slag powder with a mass ratio of 2.2:2. Example 9

[0068] The difference between Example 9 and Example 6 is that in Example 9, the solid content of the polymer emulsion is 50%. Example 10

[0069] The difference between Example 10 and Example 6 is that in Example 10, the solid content of the polymer emulsion is 65%. Example 11

[0070] The difference between Example 11 and Example 6 is that in Example 11, the film-forming aid is tributyl acetyl citrate. Example 12

[0071] The difference between Example 12 and Example 6 is that in Example 12, the total weight of the superabsorbent resin and gelatin-gum arabic complex microcapsules is 6 parts, and the weight ratio of the superabsorbent resin to the gelatin-gum arabic complex microcapsules is 1:4. Example 13

[0072] The difference between Example 13 and Example 6 is that in Example 13, the total weight of the superabsorbent resin and the gelatin-gum arabic complex microcapsules is 6 parts, and the weight ratio of the superabsorbent resin to the gelatin-gum arabic complex microcapsules is 1:6.

[0073] The concrete prepared in Examples 4 to 13 was tested for compressive strength, impermeability grade and autogenous shrinkage inhibition rate. The test results are shown in Table 2.

[0074] Table 2

[0075] As can be seen from the test results in Table 2, the difference between Example 4, Example 5 and Example 2 is that the fineness modulus of the manufactured sand is different. Among them, the concrete prepared in Example 2 has the highest compressive strength and durability.

[0076] The difference between Examples 6 and 7 and Example 2 is that the weight ratios of silica fume, fly ash and blast furnace slag powder in the mineral admixtures are different. Among them, the concrete prepared in Example 6 has the highest compressive strength and durability, and the best self-curing ability.

[0077] The difference between Example 8 and Example 6 is that the mineral admixture contains only fly ash and blast furnace slag powder, and the compressive strength and durability of the concrete prepared in Example 8 are reduced.

[0078] The difference between Examples 9 and 10 and Example 6 is that the solid content of the polymer emulsion is different. Among them, the concrete prepared in Example 6 has the highest compressive strength and durability, and the best self-curing ability.

[0079] The difference between Example 11 and Example 6 is that different film-forming aids were used. The concrete prepared in Example 11 has good compressive strength and durability, and excellent self-curing ability.

[0080] The difference between Examples 12, 13 and 6 is that the weight ratio of superabsorbent resin to gelatin-gum arabic composite microcapsules is different. Among them, the concrete prepared in Example 12 has the highest compressive strength and durability, and the best self-curing ability.

[0081] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the principles of this application should be included within the protection scope of this application.

Claims

1. A self-impregnating, high-durability polymer concrete, characterized in that, By weight, its raw material composition includes: 400-600 parts cement, 700-1000 parts fine aggregate, 1000-1300 parts coarse aggregate, 80-240 parts mineral admixture, 110-190 parts water, 40-120 parts polymer emulsion, 4-9 parts high-efficiency water-reducing agent, 2-6 parts gelatin-gum arabic complex coagulated microcapsules, 0.8-3 parts superabsorbent resin, 0.2-0.8 parts defoamer, and 1-4 parts film-forming aid.

2. The self-impregnating high-durability polymer concrete according to claim 1, characterized in that, The cement is P·II 52.5R silicate cement.

3. The self-impregnating high-durability polymer concrete according to claim 1, characterized in that, The fine aggregate is manufactured sand with a fineness modulus of 2.3 to 2.8; the coarse aggregate is crushed stone with a continuous gradation of 5 mm to 20 mm.

4. The self-impregnating high-durability polymer concrete according to claim 1, characterized in that, The mineral admixture includes at least one of silica fume, metakaolin, fly ash, blast furnace slag powder, and limestone powder.

5. The self-impregnating high-durability polymer concrete according to claim 4, characterized in that, The mineral admixture is silica fume, fly ash and blast furnace slag powder, and the weight ratio of silica fume, fly ash and blast furnace slag powder is 1:(1.5~3):(1~3).

6. The self-impregnating high-durability polymer concrete according to claim 1, characterized in that, The polymer emulsion includes at least one of acrylate emulsion, epoxy-modified acrylate emulsion, ethylene-vinyl acetate copolymer emulsion, or silicone-acrylic composite emulsion. The polymer emulsion has a solid content of 50% to 65%.

7. The self-impregnating high-durability polymer concrete according to claim 1, characterized in that, The defoamer is selected from polyether-modified silicone oil or mineral oil defoamers; The film-forming aid includes at least one of acetylated tributyl citrate, 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, and dipropylene glycol methyl ether.

8. The self-impregnating high-durability polymer concrete according to claim 1, characterized in that, The weight ratio of the superabsorbent resin to the gelatin-gum arabic composite microcapsules is 1:2~6.

9. The self-impregnating high-durability polymer concrete according to claim 1, characterized in that, The gelatin-gum arabic complex microcapsules are prepared by the following steps: Step 1: Mix choline chloride and ethylene glycol in a 1:2 molar ratio, add light mineral oil, and form the core material; Step 2: Add the core material to the gelatin aqueous solution and shear emulsify it at 40℃~50℃ and 5000rpm~8000rpm for 15min~25min to obtain an O / W emulsion; Step 3: Add gum arabic aqueous solution to the O / W emulsion, adjust the pH to 4.0~4.8, and react at 35℃~45℃ for 1h~3h; Step 4: Cool to 5℃~10℃, let stand and solidify for 2h~4h, then add 0.5%~1.0% genipin solution, adjust pH to 9~10, crosslink for 0.5h~2h, wash and dry to obtain the gelatin-gum arabic composite microcapsules; the core material accounts for 70%~80% of the total mass of the microcapsules.

10. A preparation process for self-impregnating high-durability polymer concrete according to any one of claims 1 to 9, characterized in that, Includes the following steps: Step S1: The gelatin-gum arabic complex coagulated microcapsules and the superabsorbent resin are pre-dispersed in a portion of water and swollen at room temperature for 5 min to 15 min to obtain a premixed solution; Step S2: Mix the cement, fine aggregate, coarse aggregate, and mineral admixture for 1 to 2 minutes to obtain a dry mix; Step S3: Add the high-efficiency water-reducing agent, defoamer, film-forming aid and remaining water to the dry mixture, then add the polymer emulsion and stir for 2 min to 3 min to form a slurry; Step S4: Add the premixed liquid to the slurry and continue stirring for 2 to 4 minutes to obtain concrete mix. After pouring and molding, cure naturally at room temperature to obtain self-impregnating high-durability polymer concrete.

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