Polymer anti-cracking rendering mortar based on industrial solid waste

Abstract

The application discloses a polymer anti-cracking plastering mortar based on industrial solid wastes and relates to the technical field of novel wall materials.The anti-cracking plastering mortar comprises the following raw materials in parts by weight: industrial waste residues 40-60 parts, anti-cracking fibers 0.5-2 parts, modified polymers 3-8 parts, surfactants 2-5 parts, binders 5-10 parts, cement 25-30 parts and deionized water 30-50 parts.The anti-cracking plastering mortar prepared by the application has excellent compressive strength / flexural strength ratio, tensile bonding strength and freeze-thaw resistance.

Description

Technical Field

[0001] This invention relates to the field of novel wall materials technology, specifically to a polymer-based crack-resistant plastering mortar based on industrial solid waste. Background Technology

[0002] With the popularization of building energy conservation and green construction concepts, new wall materials are widely used in engineering projects. However, these materials generally have characteristics such as low density, relatively low strength, high drying shrinkage, and high water absorption, making them prone to drying shrinkage cracks and interface delamination during use, leading to engineering problems such as water seepage, hollowing, and reduced durability. Therefore, in the construction system of new wall materials, the performance of the finishing mortar directly affects the overall quality and service life of the building. Traditional cement mortar, due to insufficient flexibility and poor compatibility with the substrate, is unable to meet the requirements of lightweight walls for crack resistance, adhesion, and long-term stability, becoming an important factor limiting the promotion of new wall materials. In recent years, polymer-modified mortar has attracted attention due to its excellent flexibility, interfacial adhesion, and crack resistance, but its cost is relatively high, and the large-scale use of cement and resin materials is not conducive to achieving the needs of low-carbon and environmentally friendly building development. Meanwhile, industrial solid waste (such as slag powder, fly ash, steel slag powder, desulfurized gypsum, etc.) contains active silica-alumina components with potential reactivity. Under alkaline conditions, these components can generate hydration products, improving the density and toughness of the matrix, making them an important green alternative to traditional cement materials. Applying the resource utilization of industrial solid waste to polymer-based crack-resistant plastering mortar can not only improve the mortar's crack resistance, durability, and compatibility with new wall materials, but also significantly reduce material costs, decrease solid waste emissions, and achieve low-carbon and recyclable building materials.

[0003] Chinese invention patent CN110482893A discloses a crack-resistant plastering mortar and its preparation method. The crack-resistant plastering mortar includes a crack-resistant agent and a plastering mortar. The mass of the crack-resistant agent is 1%-10% of the mass of the plastering mortar. The crack-resistant agent includes 60%-95% polymer composite fiber, 5%-10% surfactant, and the remainder is filler. The crack-resistant plastering mortar has good crack resistance and durability, but its tensile bond strength needs to be improved. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the purpose of this invention is to provide a polymer-based crack-resistant plastering mortar based on industrial solid waste.

[0005] To achieve the above objectives, the present invention provides the following technical solution: A polymer-based crack-resistant plastering mortar based on industrial solid waste, the crack-resistant plastering mortar comprising the following raw materials in parts by weight: industrial waste residue: 40-60 parts, crack-resistant fiber: 0.5-2 parts, modified polymer: 3-8 parts, surfactant: 2-5 parts, binder: 5-10 parts, cement: 25-30 parts, deionized water: 30-50 parts; The adhesive is prepared by the following method: S1: Lipoic acid reacts with epichlorohydrin to form an ester-based epoxy compound. S2: Ester-based epoxy compounds react with N,N,N',N'-tetra(p-aminophenyl)p-phenylenediamine to form a four-armed compound. S3: The four-armed compound reacts with oleic acid to generate a long alkyl chain modified four-armed compound. S4: A long alkyl chain modified tetra-arm compound reacts with γ-mercaptopropyltrimethoxysilane to form an adhesive; The surfactant is prepared by the following method: A1: Methyl 10-aminodecanoate reacts with sodium hydride to form a diamino compound. A2: The diamino compound reacts with 1,10-decanediol to form a tetraamino compound. A3: A tetraamino compound reacts with (3-chloro-2-hydroxypropyl)dodecyldimethylammonium chloride to form a surfactant.

[0006] In step S1, the molar ratio of thioctic acid to epichlorohydrin is 1:(1.02-1.1).

[0007] In step S2, the molar ratio of the ester-based epoxy compound to N,N,N',N'-tetratetra(p-aminophenyl)p-phenylenediamine is (4.05-4.1):1.

[0008] In step S3, the molar ratio of the four-armed compound to oleic acid is 1:(4.05-4.1).

[0009] In step S4, the molar ratio of the long alkyl chain modified tetra-arm compound to γ-mercaptopropyltrimethoxysilane is 1:(4.04-4.1).

[0010] In step A2, the molar ratio of the diamino compound to 1,10-decanediol is 2.03:1.

[0011] In step A3, the tetraamino compound is mixed with (3-chloro-2-hydroxypropyl)dodecyl dimethylammonium chloride at a ratio of 1:4.05.

[0012] The crack-resistant fiber is polypropylene fiber.

[0013] The modified polymer is a mixture of ethylene-vinyl acetate copolymer and vinyl acetate-ethylene copolymer latex powder in a weight ratio of 1:(0.5-1.5).

[0014] The method for preparing the crack-resistant plastering mortar is as follows: weigh each component according to the raw material composition, mix cement and deionized water, and then add industrial waste residue, crack-resistant fiber, modified polymer, surfactant and binder in sequence. After stirring and mixing evenly, the crack-resistant plastering mortar is obtained.

[0015] Due to the adoption of the above technical solutions, the beneficial effects of the present invention include: The crack-resistant plastering mortar prepared in this application, as a novel wall material, has excellent compressive strength / flexural strength ratio, tensile bond strength, and freeze-thaw resistance. Detailed Implementation

[0016] The following description, in conjunction with specific embodiments, provides further details, but the present invention is not limited to these embodiments.

[0017] Example 1: Preparation of adhesive: S1: Add 150 ml toluene, 0.1 mol lipoic acid, 0.01 mol TEBAC (benzyltriethylammonium chloride), and 110 ml 1M NaOH aqueous solution to the reactor, stir and mix well, then add 0.102 mol epichlorohydrin, heat to 40℃ and react for 4 h, then add 2 wt% dilute hydrochloric acid to adjust the pH to neutral, allow to stand and separate, wash the organic phase three times with saturated brine (50 ml each time), then dry with 10 g anhydrous sodium sulfate, filter, rotary evaporate at 50℃ for 2 h, and vacuum dry at 50℃ for 12 h to obtain the ester-based epoxy compound; the reaction equation is shown below:

[0018] Its 1H NMR data are as follows: 1 H NMR (400 MHz, Chloroform- d ) δ 4.34 (dd, J =11.5, 3.4 Hz, 1H), 4.09 (dd, J = 11.5, 3.4 Hz, 1H), 3.62 – 3.53 (m, 1H), 3.47(tt, J = 4.2, 3.4 Hz, 1H), 3.29 – 2.89 (m, 4H), 2.40 – 2.34 (m, 2H), 2.33 –2.01 (m, 2H), 1.76 – 1.30 (m, 6H).

[0019] S2: Under nitrogen protection, 600 ml of DMF (N,N-dimethylformamide), 0.1 mol of N,N,N',N'-tetra(p-aminophenyl)-p-phenylenediamine, and 30 g of anhydrous potassium carbonate were added to the reactor. The mixture was heated to 35 °C and stirred for 20 min. Then, 0.405 mol of ester-based epoxy compound was added in batches (5 batches, 5 min apart), stirred and mixed thoroughly. The mixture was heated to 70 °C and reacted for 8 h. The reaction solution was poured into 800 ml of ice water, stirred to precipitate, filtered, and the solid was collected. The solid was washed three times with deionized water (100 ml each time) and dried under vacuum at 45 °C for 12 h to obtain the four-armed compound. The reaction equation is shown below:

[0020] Its 1H NMR data are as follows: 1 H NMR (400 MHz, Chloroform- d ) δ 7.16 – 7.01 (m,12H), 6.72 – 6.62 (m, 8H), 5.01 (t, J = 6.3 Hz, 4H), 4.31 (dd, J = 12.3, 5.1Hz, 4H), 4.14 (d, J = 5.6 Hz, 4H), 4.09 – 4.00 (m, 8H), 3.50 – 3.39 (m, 8H), 3.23 – 3.01 (m, 12H), 2.43 – 2.25 (m, 12H), 2.04 (m, 4H), 1.79 – 1.28 (m, 24H).

[0021] S3: Under nitrogen protection, 1000 ml of toluene, 0.1 mol of the four-arm compound, and 0.405 mol of oleic acid were added to the reactor and stirred until homogeneous. The mixture was heated to 90 °C, and then 3 g of p-toluenesulfonic acid was added. The reaction was carried out for 6 h (water generated during the reaction was removed using a water separator). After cooling to room temperature, saturated sodium bicarbonate solution was slowly added to adjust the pH to 7. The mixture was stirred thoroughly for 30 min, allowed to stand for separation, and the organic phase was transferred to a rotary evaporator and rotary evaporated at 60 °C for 1 h to obtain the long alkyl chain modified four-arm compound. The reaction equation is shown below:

[0022] Its 1H NMR data are as follows: 1 H NMR (400 MHz, Chloroform- d) δ 7.16 – 7.01 (m,12H), 6.72 – 6.62 (m, 8H), 5.54 – 5.28 (m, 12H), 5.03 (p, J = 4.8 Hz, 4H), 4.50 (dd, J = 12.8, 4.8 Hz, 4H), 4.24 (dd, J = 12.8, 4.8 Hz, 4H), 3.70 (ddd,J = 13.9, 6.0, 4.9 Hz, 4H), 3.52 – 3.37 (m, 8H), 3.18 (ddd, J = 12.4, 4.5,2.6 Hz, 4H), 3.05 (ddd, J = 12.4, 4.5, 2.6 Hz, 4H), 2.42 – 2.23 (m, 20H), 2.09 – 1.96 (m, 20H), 1.76 – 1.21 (m, 112H), 0.97 – 0.83 (m, 12H).

[0023] S4: Under nitrogen protection, add 1200 ml of tetrahydrofuran, 0.1 mol of a long alkyl chain modified four-arm compound, 0.404 mol of γ-mercaptopropyltrimethoxysilane, and 0.6 g of photoinitiator 184 to the reactor, stir and mix thoroughly, at an intensity of 8.4 mW / cm². 2 After irradiation under a 365nm UV LED lamp for 8 hours, the mixture was rotary evaporated at 40℃ for 1 hour. The precipitate was then slowly added to 800mL of cold diethyl ether, stirred, filtered, and washed three times with 100mL of cold diethyl ether each time. The final product was then vacuum dried at 40℃ for 12 hours to obtain the binder. The reaction equation is shown below:

[0024] Its 1H NMR data are as follows: 1 H NMR (400 MHz, Chloroform- d) δ 7.15 – 7.02 (m,12H), 6.70 – 6.63 (m, 8H), 5.43 (t, J = 6.0 Hz, 4H), 5.07 – 4.98 (m, 4H), 4.50 (dd, J = 12.8, 4.8 Hz, 4H), 4.24 (dd, J = 12.8, 4.8 Hz, 4H), 3.70 (ddd,J = 13.9, 6.0, 4.9 Hz, 4H), 3.59 (s, 36H), 3.51 – 3.40 (m, 8H), 3.18 (ddd, J= 12.4, 4.5, 2.6 Hz, 4H), 3.05 (ddd, J = 12.4, 4.5, 2.6 Hz, 4H), 2.79 (p, J =5.8 Hz, 4H), 2.56 (dt, J = 13.2, 7.6 Hz, 4H), 2.48 – 2.25 (m, 24H), 2.04 (m,4H), 1.77 – 1.20 (m, 144H), 0.93 – 0.86 (m, 12H), 0.83 – 0.74 (m, 8H).

[0025] Example 2: Preparation of adhesive: S1: Add 150 ml toluene, 0.1 mol lipoic acid, 0.01 mol TEBAC, and 110 ml 1M NaOH aqueous solution to the reactor, stir and mix well, then add 0.105 mol epichlorohydrin, heat to 45℃ and react for 3.5 h, then add 2 wt% dilute hydrochloric acid to adjust the pH to neutral, let stand and separate the liquids, wash the organic phase three times with saturated brine (50 ml each time), then dry with 10 g anhydrous sodium sulfate, filter, rotary evaporate at 50℃ for 2 h, and vacuum dry at 50℃ for 12 h to obtain ester-based epoxy compound; S2: Under nitrogen protection, 600 ml DMF, 0.1 mol N,N,N',N'-tetra(p-aminophenyl)p-phenylenediamine, and 30 g anhydrous potassium carbonate were added to the reactor. The mixture was heated to 35 °C and stirred for 20 min. Then, 0.408 mol of ester-based epoxy compound was added in batches (5 batches, 5 min apart). The mixture was stirred and stirred until homogeneous. The mixture was heated to 75 °C and reacted for 7.5 h. The reaction solution was poured into 800 ml of ice water and stirred to precipitate. The precipitate was filtered, collected, and washed three times with deionized water (100 ml each time). The solid was dried under vacuum at 45 °C for 12 h to obtain the four-armed compound. S3: Under nitrogen protection, 1000 ml of toluene, 0.1 mol of the four-arm compound, and 0.408 mol of oleic acid were added to the reactor and stirred until homogeneous. The mixture was heated to 95 °C, and then 3 g of p-toluenesulfonic acid was added. The reaction was carried out for 5.5 h (water generated during the reaction was removed using a water separator). The mixture was then cooled to room temperature, and saturated sodium bicarbonate solution was slowly added to adjust the pH to 7. The mixture was stirred thoroughly for 30 min, allowed to stand and separate into layers, and the organic phase was transferred to a rotary evaporator and rotary evaporated at 60 °C for 1 h to obtain the long alkyl chain modified four-arm compound. S4: Under nitrogen protection, add 1200 ml of tetrahydrofuran, 0.1 mol of a long alkyl chain modified four-arm compound, 0.407 mol of γ-mercaptopropyltrimethoxysilane, and 0.6 g of photoinitiator 184 to the reactor, stir and mix thoroughly, at an intensity of 8.4 mW / cm². 2 After irradiation under a 365nm ultraviolet LED lamp for 8 hours, the mixture was rotary evaporated at 40℃ for 1 hour, then slowly added to 800mL of cold ether, stirred, and the precipitate was precipitated. The precipitate was filtered, washed three times with cold ether (100mL each time), and then vacuum dried at 40℃ for 12 hours to obtain the binder.

[0026] Example 3: Preparation of adhesive: S1: Add 150 ml toluene, 0.1 mol lipoic acid, 0.01 mol TEBAC, and 110 ml 1M NaOH aqueous solution to the reactor, stir and mix well, then add 0.11 mol epichlorohydrin, heat to 50℃ and react for 3 h, then add 2 wt% dilute hydrochloric acid to adjust the pH to neutral, let stand and separate the liquids, wash the organic phase three times with saturated brine (50 ml each time), then dry with 10 g anhydrous sodium sulfate, filter, rotary evaporate at 50℃ for 2 h, and vacuum dry at 50℃ for 12 h to obtain ester-based epoxy compound; S2: Under nitrogen protection, 600 ml DMF, 0.1 mol N,N,N',N'-tetra(p-aminophenyl)p-phenylenediamine, and 30 g anhydrous potassium carbonate were added to the reactor. The mixture was heated to 35 °C and stirred for 20 min. Then, 0.41 mol of ester-based epoxy compound was added in batches (5 batches, 5 min apart). The mixture was stirred and stirred until homogeneous. The mixture was heated to 80 °C and reacted for 7 h. The reaction solution was poured into 800 ml of ice water and stirred to precipitate. The precipitate was filtered, collected, and washed three times with deionized water (100 ml each time). The solid was dried under vacuum at 45 °C for 12 h to obtain the four-armed compound. S3: Under nitrogen protection, 1000 ml of toluene, 0.1 mol of the four-arm compound, and 0.41 mol of oleic acid were added to the reactor and stirred until homogeneous. The mixture was heated to 100 °C, and then 3 g of p-toluenesulfonic acid was added. After reacting for 5 h (using a water separator to remove the generated water during the reaction), the mixture was cooled to room temperature. Saturated sodium bicarbonate solution was slowly added to adjust the pH to 7. The mixture was stirred thoroughly for 30 min, allowed to stand and separate into layers, and the organic phase was transferred to a rotary evaporator and rotary evaporated at 60 °C for 1 h to obtain the long alkyl chain modified four-arm compound. S4: Under nitrogen protection, add 1200 ml of tetrahydrofuran, 0.1 mol of a long alkyl chain modified four-arm compound, 0.41 mol of γ-mercaptopropyltrimethoxysilane, and 0.6 g of photoinitiator 184 to the reactor, stir and mix thoroughly, at an intensity of 8.4 mW / cm². 2 After irradiation under a 365nm ultraviolet LED lamp for 8 hours, the mixture was rotary evaporated at 40℃ for 1 hour, then slowly added to 800mL of cold ether, stirred, and the precipitate was precipitated. The precipitate was filtered, washed three times with cold ether (100mL each time), and then vacuum dried at 40℃ for 12 hours to obtain the binder.

[0027] Example 4: Preparation of surfactants: A1: Under nitrogen protection, 120 mL of deionized water and 30 mL of acetone were added to the reactor, followed by 0.1 mol of methyl 10-aminodecanoate. The mixture was stirred and dissolved, and then 0.2 mol of NaHCO3 was added. At 0 °C, 100 mL of an acetone solution containing 0.105 mol of fluorenyl chloroformate was slowly added dropwise over 20 min. The mixture was stirred for another 30 min, then brought to room temperature and stirred for 1 h. After stirring, 100 mL of deionized water was added, and the mixture was extracted three times with ethyl acetate (150 mL each time). The extract was washed with 50 mL of 0.5 M hydrochloric acid, 50 mL of deionized water, and 50 mL of saturated brine, respectively. The extract was dried over 10 g of anhydrous sodium sulfate, filtered, and then rotary evaporated at 45 °C for 1 h. Finally, the extract was vacuum dried at 50 °C for 12 h to obtain amino-protected methyl decanoate. Under nitrogen protection, 150 ml of anhydrous DMF was added to the reactor, followed by 0.11 mol of sodium hydride in five batches (5 min apart). Under ice bath conditions, a DMF solution of amino-protected methyl decanoate was slowly added dropwise (the amino-protected methyl decanoate prepared above was dissolved in 200 ml of DMF). Add DMF dropwise over 30 minutes. After the addition is complete, heat to 50°C and react for 8 hours. Cool to 0°C and slowly add 150 ml of saturated ammonium chloride aqueous solution to quench the reaction. Dilute with 200 ml of deionized water, then extract three times with ethyl acetate (150 ml each time). Combine the organic phases and wash with 100 ml of saturated brine. Dry with 15 g of anhydrous sodium sulfate, filter, rotary evaporate at 45°C for 1 hour, and vacuum dry at 50°C for 12 hours to obtain the Fmoc-protected intermediate. Add the Fmoc-protected intermediate to 150 ml of a mixed solution of DMF and piperidine (DMF to piperidine volume ratio 4:1), stir at 25°C for 60 minutes to deprotect, rotary evaporate at 60°C for 1 hour, and vacuum dry at 50°C for 12 hours to obtain the diamino compound. The reaction equation is shown below:

[0028] Its 1H NMR data are as follows: 1 H NMR (400 MHz, Chloroform- d ) δ 3.69 (s, 3H), 3.56 (t, J = 7.3 Hz, 1H), 2.66 (tt, J = 6.5, 5.2 Hz, 4H), 2.57 – 2.33 (m, 2H), 1.96 – 1.18 (m, 32H).

[0029] A2: Under nitrogen protection, 600 mL of xylene, 0.203 mol of the diamino compound, 0.1 mol of 1,10-decanediol, and 0.01 mol of dibutyltin oxide were added to the reactor. The mixture was stirred and stirred until homogeneous. After reflux for 6 h (methanol was removed using a Dean-Stark apparatus during the reaction), the mixture was cooled to room temperature, washed three times with saturated brine (100 mL each time), dried with 20 g of anhydrous magnesium sulfate, filtered, and the filtrate was rotary evaporated at 60 °C for 1.5 h and then vacuum dried at 70 °C for 12 h to obtain the tetraamino compound. The reaction equation is shown below:

[0030] Its 1H NMR data are as follows: 1 H NMR (400 MHz, Chloroform- d) δ 4.31 – 4.05 (m,4H), 3.54 (t, J = 7.7 Hz, 2H), 2.66 (tt, J = 6.5, 5.2 Hz, 8H), 2.59 – 2.33(m, 4H), 1.87 (dtd, J = 13.6, 8.5, 7.7 Hz, 2H), 1.71 – 1.19 (m, 78H).

[0031] A3: Add 1000 ml anhydrous ethanol, 0.1 mol tetraamino compound, and 0.41 mol triethylamine to the reactor. Heat to 35°C and stir for 20 min. Then add 0.405 mol (3-chloro-2-hydroxypropyl) dodecyl dimethyl ammonium chloride in 5 batches (5 min intervals between batches), stir to mix, heat to 60°C and react for 8 h. Filter, rotary evaporate at 40°C for 1.5 h, pour the reaction solution into 800 ml acetone, stir to precipitate, filter, collect the solid, wash three times with acetone (150 ml acetone each time), and vacuum dry at 45°C for 12 h to obtain the surfactant. The reaction equation is shown below:

[0032] Its 1H NMR data are as follows: 1 H NMR (400 MHz, Chloroform- d ) δ 5.83 (d, J = 6.1Hz, 4H), 4.25 – 4.03 (m, 12H), 3.65 – 3.34 (m, 18H), 3.32 (s, 12H), 3.19 (s,12H), 2.95 (ddd, J = 12.8, 6.0, 5.2 Hz, 4H), 2.76 – 2.64 (m, 12H), 2.57 –2.33 (m, 4H), 1.94 – 1.21 (m, 152H), 0.94 – 0.83 (m, 12H).

[0033] Example 5: Preparation of crack-resistant plastering mortar: (1) Weigh: Industrial waste residue: 400g, crack-resistant fiber (polypropylene fiber): 5g, modified polymer (20g ethylene-vinyl acetate copolymer + 10g vinyl acetate-ethylene copolymer latex powder): 30g, surfactant (prepared in Example 4): 20g, binder (prepared in Example 1): 50g, cement: 250g, deionized water: 300g; (2) Mix cement and deionized water at 200 rpm for 10 min until homogeneous, and then add industrial waste residue, crack-resistant fiber, modified polymer, surfactant and binder in sequence. Mix at 300 rpm for 20 min until homogeneous to obtain crack-resistant plastering mortar.

[0034] Example 6: Preparation of crack-resistant plastering mortar: (1) Weigh: Industrial waste residue: 500g, crack-resistant fiber (polypropylene fiber): 10g, modified polymer (25g ethylene-vinyl acetate copolymer + 25g vinyl acetate-ethylene copolymer latex powder): 50g, surfactant (prepared in Example 4): 35g, binder (prepared in Example 2): 80g, cement: 280g, deionized water: 400g; (2) Mix cement and deionized water at 200 rpm for 10 min until homogeneous, and then add industrial waste residue, crack-resistant fiber, modified polymer, surfactant and binder in sequence. Mix at 300 rpm for 20 min until homogeneous to obtain crack-resistant plastering mortar.

[0035] Example 7: Preparation of crack-resistant plastering mortar: (1) Weigh: industrial waste residue: 600g, crack-resistant fiber (polypropylene fiber): 20g, modified polymer (32g ethylene-vinyl acetate copolymer + 48g vinyl acetate-ethylene copolymer latex powder): 80g, surfactant (prepared in Example 4): 50g, binder (prepared in Example 3): 100g, cement: 300g, deionized water: 500g; (2) Mix cement and deionized water at 200 rpm for 10 min until homogeneous, and then add industrial waste residue, crack-resistant fiber, modified polymer, surfactant and binder in sequence. Mix at 300 rpm for 20 min until homogeneous to obtain crack-resistant plastering mortar.

[0036] Comparative Example 1 The composition and preparation method of the crack-resistant plastering mortar are basically the same as in Example 6, except that the binder is replaced with an equal weight of binder prepared by the following method: The preparation method of the adhesive is basically the same as that in Example 2, except that the lipoic acid in step S1 is replaced with an equimolar amount of n-octanoic acid.

[0037] Comparative Example 2 The composition and preparation method of the crack-resistant plastering mortar are basically the same as in Example 6, except that the binder is replaced with an equal weight of binder prepared by the following method: The preparation method of the adhesive is basically the same as that in Example 2, except that N,N,N',N'-tetra(p-aminophenyl)p-phenylenediamine in step S2 is replaced with an equimolar amount of 4,4'-diaminodiphenylamine.

[0038] Comparative Example 3 The composition and preparation method of the crack-resistant plastering mortar are basically the same as in Example 6, except that the binder is replaced with an equal weight of binder prepared by the following method: The preparation method of the adhesive is basically the same as that in Example 2, except that oleic acid in step S3 is replaced with an equimolar amount of 9-decenoic acid.

[0039] Comparative Example 4 The composition and preparation method of the crack-resistant plastering mortar are basically the same as in Example 6, except that the binder is replaced with an equal weight of binder prepared by the following method: The preparation method of the adhesive is basically the same as that in Example 2, except that γ-mercaptopropyltrimethoxysilane in step S4 is replaced with an equimolar amount of 3-(methoxydimethylsilyl)propanethiol.

[0040] Comparative Example 5 The composition and preparation method of the crack-resistant plastering mortar raw materials are basically the same as those in Example 6, except that the surfactant is replaced with an equal weight of surfactant prepared by the following method: The preparation method of the surfactant is basically the same as that in Example 4, except that 1,10-decanediol in step A2 is replaced with an equimolar amount of 1,6-hexanediol.

[0041] Comparative Example 6 The composition and preparation method of the crack-resistant plastering mortar raw materials are basically the same as those in Example 6, except that the surfactant is replaced with an equal weight of surfactant prepared by the following method: The preparation method of the surfactant is basically the same as that in Example 4, except that (3-chloro-2-hydroxypropyl)dodecyl dimethyl ammonium chloride in step A3 is replaced with an equimolar amount of 3-chloro-2-hydroxypropyltrimethyl ammonium chloride.

[0042] Comparative Example 7 The composition and preparation method of the crack-resistant plastering mortar raw materials are basically the same as those in Example 6, except that the surfactant is replaced with an equal weight of surfactant prepared by the following method: Under nitrogen protection, 600 mL of xylene, 0.1 mol of methyl 10-aminodecanoate, 0.202 mol of 1,10-decanediol, and 0.01 mol of dibutyltin oxide were added to the reactor. The mixture was stirred and stirred until homogeneous. After reflux for 6 h (methanol was removed using a Dean-Stark apparatus during the reaction), the mixture was cooled to room temperature, washed three times with saturated brine (100 mL each time), dried with 20 g of anhydrous magnesium sulfate, filtered, and the filtrate was rotary evaporated at 60 °C for 1.5 h and then vacuum dried at 70 °C for 12 h to obtain the diamino compound. Add 1000 ml of anhydrous ethanol, 0.1 mol of diamino compound, and 0.21 mol of triethylamine to the reactor, heat to 35 °C and stir for 20 min. Then add 0.205 mol of (3-chloro-2-hydroxypropyl)dodecyl dimethyl ammonium chloride in 5 batches with a 5 min interval between batches, stir and mix well, heat to 40 °C and react for 8 h. Then, rotary evaporate at 40 °C for 1.5 h. After the reaction is complete, pour the reaction solution into 800 ml of acetone, stir to precipitate, filter, collect the solid, wash three times with acetone (150 ml of acetone each time), and vacuum dry at 45 °C for 12 h to obtain the surfactant.

[0043] The industrial waste used in the embodiments and comparative examples of this application is mainly a mixture of fly ash and slag, with a mass ratio of fly ash to slag of 2:3. The main components of fly ash are silicon dioxide (54.9 wt%), aluminum oxide (26.4 wt%), ferric oxide (11.2 wt%), and calcium oxide (5.8 wt%), with a particle size mainly concentrated in the range of 0.45-0.85 mm. The main components of slag are silicon dioxide (31.9 wt%), calcium oxide (36.2 wt%), aluminum oxide (17.2 wt%), and magnesium oxide (13.5 wt%), with a particle size concentrated in the range of 1-3 mm. The cement is grade 42.5 road silicate cement (code P.R7.5), purchased from Shanxi Zhuoyue Cement Co., Ltd. The vinyl acetate-ethylene copolymer latex powder is model VINNAPAS®4023N(PRC). The ethylene-vinyl acetate copolymer is model ExxonMobil. TM EVA MF28; the polypropylene fiber is a bundled monofilament with a diameter of 18-65μm and a specification of 3-30mm, produced by Shandong Shunying Engineering Materials Co., Ltd.

[0044] The crack-resistant plastering mortars prepared in Examples 5-7 and Comparative Examples 1-7 of this application were tested for compressive strength / flexural strength, tensile bond strength, and frost resistance. The test results are shown in Table 1.

[0045] Sample preparation: The crack-resistant plastering mortar prepared according to Examples 5-7 and Comparative Examples 1-7 was poured into rigid polyvinyl chloride molds and vibrated to form the mortar. After 24 hours, the mortar was demolded and cured in water at (23±2)℃ for 6 days, and then placed at (23±2)℃ and 45-75% relative humidity for 21 days. Before the test, the molded surface of the cement mortar specimen was smoothed with 200# sandpaper or a grinding stone.

[0046] Compressive strength / flexural strength test: The compressive strength and flexural strength are tested in accordance with GBT17671-2021 "Test Method for Strength of Cement Mortar (ISO Method)". When preparing the sample, a 40mm×40mm×160mm mold is selected, and the ratio of compressive strength to flexural strength is calculated.

[0047] Tensile bond strength: The tensile bond strength was tested according to the test method in Part 10 of JGJ70-2009 "Standard for Test Methods of Basic Performance of Building Mortar". A 70mm×70mm×20mm mold was selected for sample preparation.

[0048] Freeze-thaw resistance test: The freeze-thaw resistance was tested according to the test method in Part 11 of JGJ70-2009 "Standard for Test Methods of Basic Performance of Building Mortar". A mold of 70.7mm×70.7mm×70.7mm was selected when preparing the sample.

[0049] Table 1 Performance Indicators of Crack-Resistant Plastering Mortar

[0050] As can be seen from Table 1, the crack-resistant plastering mortars prepared in Examples 5-7 of this application have excellent compressive strength / flexural strength ratio, tensile bond strength and freeze-thaw resistance.

[0051] The binder added to the plastering mortar prepared in this application is a three-dimensional network framework with a rigid conjugated aromatic plane as its core, and the introduced multiple benzene rings are connected through sp 2The hybridized large π bonds and multiple benzene ring structures effectively transfer and disperse the stress on the plastering mortar; the flexible long alkyl chains introduced into the binder can disperse and absorb the energy generated by external loads, preventing crack propagation and thus improving the toughness and flexural strength of the material; the introduced methoxysilanes hydrolyze in the mortar hydration environment to generate highly active silanol groups. These silanol groups can condense with the hydroxyl groups on the surface of cement particles in the mortar to form -Si-O- covalent bonds (chemical anchoring), and can also condense among themselves to form a siloxane network, enhancing the bonding between the binder and inorganic materials (cement). The interfacial bonding force between the mortar and the microcracks (etc.) is improved, enhancing the tensile bond strength. The disulfide bonds introduced in the binder can undergo reversible fracture and recombination reactions under stress. When the mortar is subjected to external stress, the stress will concentrate at microcracks or weak points. In these local high-stress areas, the original disulfide bonds will break. However, the sulfur free radicals generated by the new fracture will immediately exchange with the disulfide bonds on the adjacent molecular chains to reform a disulfide bond. Through bond recombination, excessive stress concentration is avoided, and the propagation of microcracks is prevented, thereby significantly improving the toughness and tensile bond strength of the mortar.

[0052] The cross-linking network of the binder used in Comparative Example 2 has poor density and integrity. The sparse cross-linking network is difficult to effectively transfer and disperse stress, resulting in insufficient compressive and flexural strength of the material. Furthermore, it is difficult to form a dense three-dimensional hydrophobic barrier, which also reduces freeze-thaw resistance.

[0053] The four quaternary ammonium salt cations in the surfactant added to the plastering mortar prepared in this application serve as strong hydrophilic and adsorption centers, connected by flexible long-chain ester bonds. During mortar mixing, the positively charged quaternary ammonium salt head groups are tightly "anchored" to the negatively charged cement particles and hydration products through strong electrostatic interactions, making the molecules more stable. The long-chain alkyl groups in the molecules are hydrophobic, which can reduce the surface tension of the mortar and inhibit the coalescence and growth of air bubbles, making the air generated during mixing more easily stabilized into a small, uniformly distributed closed bubble structure. During freeze-thaw cycles, these uniform and stable micro-air-entraining pores can serve as effective stress release spaces, buffering the volume expansion pressure caused by the freezing of capillary water, and reducing the initiation and propagation of microcracks caused by stress concentration. The strong adsorption of the multi-quaternary ammonium salt groups and the interfacial regulation effect of the hydrophobic segments form a synergistic effect, enabling the mortar to exhibit excellent crack resistance in freeze-thaw environments, thereby significantly improving freeze-thaw durability.

[0054] The surfactant used in Comparative Example 6 has a shorter alkyl chain, which weakens its hydrophobic effect and intermolecular forces, making it difficult to form an effective protective film at the interface. This makes it easy for bubbles introduced by stirring to merge, break, or escape. As a result, it is difficult to form an effective porous structure system to buffer frost heave stress inside the mortar, thus reducing its freeze-thaw resistance.

[0055] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. However, any modifications, alterations, and variations made by those skilled in the art without departing from the scope of the present invention based on the disclosed technical content are equivalent embodiments of the present invention. Furthermore, any modifications, alterations, and variations made to the above embodiments based on the essential technology of the present invention are still within the protection scope of the present invention.

Claims

1. A polymer-based crack-resistant plastering mortar based on industrial solid waste, characterized in that, The ingredients include the following parts by weight: Industrial waste residue: 40-60 parts, crack-resistant fiber: 0.5-2 parts, modified polymer: 3-8 parts, surfactant: 2-5 parts, binder: 5-10 parts, cement: 25-30 parts, deionized water: 30-50 parts; The modified polymer is a mixture of ethylene-vinyl acetate copolymer and vinyl acetate-ethylene copolymer latex powder in a weight ratio of 1:(0.5-1.5); The adhesive is prepared by the following method: S1: Lipoic acid reacts with epichlorohydrin to form an ester-based epoxy compound, and the reaction equation is shown below: ； S2: The ester-based epoxy compound reacts with N,N,N',N'-tetra(p-aminophenyl)p-phenylenediamine to form a four-armed compound, as shown in the following schematic equation: ； S3: The four-armed compound reacts with oleic acid to generate a long alkyl chain modified four-armed compound, and the reaction equation is shown below: ； S4: The long alkyl chain modified tetra-arm compound reacts with γ-mercaptopropyltrimethoxysilane to form an adhesive, and the reaction equation is shown below: ； The surfactant is prepared by the following method: A1: Methyl 10-aminodecanoate reacts with sodium hydride to form a diamino compound, as shown in the following schematic equation: ； A2: The diamino compound reacts with 1,10-decanediol to form a tetraamino compound, as shown in the following schematic equation: ； A3: A tetraamino compound reacts with (3-chloro-2-hydroxypropyl)dodecyldimethylammonium chloride to form a surfactant, as shown in the following schematic equation: 。 2. The polymer-based crack-resistant plastering mortar based on industrial solid waste according to claim 1, characterized in that, In step S1, the molar ratio of thioctic acid to epichlorohydrin is 1:(1.02-1.1).

3. The polymer-based crack-resistant plastering mortar based on industrial solid waste according to claim 1, characterized in that, In step S2, the molar ratio of the ester-based epoxy compound to N,N,N',N'-tetratetra(p-aminophenyl)p-phenylenediamine is (4.05-4.1):

1.

4. The polymer-based crack-resistant plastering mortar based on industrial solid waste according to claim 1, characterized in that, In step S3, the molar ratio of the four-armed compound to oleic acid is 1:(4.05-4.1).

5. The polymer-based crack-resistant plastering mortar based on industrial solid waste according to claim 1, characterized in that, In step S4, the molar ratio of the long alkyl chain modified tetra-arm compound to γ-mercaptopropyltrimethoxysilane is 1:(4.04-4.1).

6. The polymer-based crack-resistant plastering mortar based on industrial solid waste according to claim 1, characterized in that, In step A2, the molar ratio of the diamino compound to 1,10-decanediol is 2.03:

1.

7. The polymer-based crack-resistant plastering mortar based on industrial solid waste according to claim 1, characterized in that, In step A3, the molar ratio of the tetraamino compound to (3-chloro-2-hydroxypropyl)dodecyl dimethyl ammonium chloride is 1:4.

05.

8. The polymer-based crack-resistant plastering mortar based on industrial solid waste according to claim 1, characterized in that, The crack-resistant fiber is polypropylene fiber.

9. The polymer-based crack-resistant plastering mortar based on industrial solid waste according to claim 1, characterized in that, The method for preparing the crack-resistant plastering mortar is as follows: weigh each component according to the raw material composition, mix cement and deionized water, and then add industrial waste residue, crack-resistant fiber, modified polymer, surfactant and binder in sequence. After stirring and mixing evenly, the crack-resistant plastering mortar is obtained.

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