Mortar containing nano material and preparation method thereof

Abstract

The invention relates to the technical field of building materials, and discloses a mortar containing a nanometer material and a preparation method thereof, the mortar comprises 70-80 parts by weight of cement, 8-12 parts by weight of fly ash, 0.4-0.5 part by weight of a polycarboxylic acid water reducer, 0.4-0.6 part by weight of hydroxypropyl methyl cellulose, 1-2 parts by weight of the nanometer material, 2-3 parts by weight of modified silk fibroin and 40-50 parts by weight of water. Wherein the modified nano silicon dioxide is modified by gamma-aminopropyltriethoxysilane, the modified cubic nano calcium carbonate is subjected to compound modification by fumaric acid, sodium stearate and palmitic acid, and the modified silk fibroin is prepared by grafting modification by bis-aminopropyl terminated polysiloxane. According to the mortar, through optimization of component matching and modification treatment of the nano material and the silk fibroin, the mechanical property, durability and crack resistance of the mortar are remarkably improved, and the cost is controllable.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of building materials, in particular to a mortar containing nanomaterials and a preparation method thereof. BACKGROUND

[0002] The mortar is a basic material with a large amount of use in building engineering, mainly used in wall plastering, masonry, ceramic tile sticking, thermal insulation layer protection and other scenes, and its performance directly affects the durability and use safety of the building structure. The traditional mortar mainly uses cement, sandstone and water as main raw materials, although the cost is low, but it has problems of insufficient compressive strength and poor weather resistance, and in the long-term use process, it is easy to appear cracking, falling off and other diseases, which seriously affects the quality of building engineering. In the prior art, the modification is carried out by adding water reducing agent, water retaining agent or mineral admixture, but the effect is limited.

[0003] The nanoparticles have unique physical and chemical properties due to their extremely small particle size and extremely large specific surface area, and the application of the nanoparticles in the mortar can optimize the internal structure of the mortar through the filling effect, but the addition of a single nanomaterial is easy to agglomerate, which leads to uneven dispersion of the nanoparticles in the mortar, and thus affects the modification effect. Therefore, it has important practical significance to develop a mortar containing nanomaterials with excellent performance and controllable cost. SUMMARY

[0004] Technical problems to be solved

[0005] In view of the defects in the prior art, the present application provides a mortar containing nanomaterials and a preparation method thereof, which has good mechanical properties and durability and crack resistance.

[0006] Technical scheme

[0007] To achieve the above-mentioned purpose, the present application provides the following technical scheme: a mortar containing nanomaterials, comprising the following components by weight: 70-80 parts by weight of cement, 8-12 parts by weight of fly ash, 0.4-0.5 parts by weight of polycarboxylate superplasticizer, 0.4-0.6 parts by weight of hydroxypropyl methylcellulose, 1-2 parts by weight of nanomaterials, 2-3 parts by weight of modified silk fibroin, and 40-50 parts by weight of water.

[0008] Further, the nanomaterials comprise the following components by weight: 0.5-1 parts by weight of modified cubic-shaped nanometer calcium carbonate, and 0.5-1 parts by weight of modified nanometer silicon dioxide.

[0009] The preparation method of the modified nanometer silicon dioxide is: 45 mL of anhydrous ethanol and 15 mL of deionized water are added to a reactor to prepare a solution, then 1-2 g of nanometer silicon dioxide is added, ultrasonic treatment is performed for 35-40 min, then 0.04-0.08 g of γ-aminopropyl triethoxysilane is added, and the pH of the system is adjusted to 4 with hydrochloric acid, and reflux reaction is performed at 45-50°C for 1-2 h, after the reaction is completed, centrifugation, washing and drying are performed to obtain the modified nanometer silicon dioxide.

[0010] Further, the preparation method of the modified cubic nanometer calcium carbonate is:

[0011] a. 2-3 g of Ca(OH)2 is placed in a high gravity micro-interface reactor, the circulating pump and cooling device are turned on, when the reaction temperature reaches 25°C, the CO2 gas flow meter is opened, the volume flow rate is set to 3 m 3 / h (standard condition) until the reaction endpoint pH=7, the reaction is completed, the flow meter and the circulating pump are turned off, and the nanometer calcium carbonate is obtained;

[0012] b. Fumaric acid, sodium stearate and palmitic acid are added to an ethanol solvent, ultrasonic treatment is performed for 10-15 min, the mixture is uniformly mixed to obtain a mixed solution; then the mixed solution is added to 1-1.8 g of nanometer calcium carbonate, and reaction is performed at 65-70°C, after the reaction is completed, filtration is performed, and the modified cubic nanometer calcium carbonate is obtained after drying in an oven.

[0013] Further, in step b, the amount ratio of fumaric acid, sodium stearate, palmitic acid and ethanol is 0.02-0.03 g: 0.031-0.035 g: 0.02-0.036 g: 8-10 mL.

[0014] Further, in step b, the reaction time is 40-45 min.

[0015] Further, the preparation method of the modified silk fibroin is:

[0016] S1. Octamethylcyclotetrasiloxane, 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane and tetramethylammonium hydroxide are added to a reaction bottle, stirring is performed under nitrogen protection, heating is performed to 85-90°C, reaction is performed for 3-4 h, then the temperature is increased to 135-140°C, and reaction is continued for 1-1.5 h, after the reaction is completed, vacuum is extracted by a vacuum pump, and reduced pressure distillation is performed to obtain bisaminopropyl terminated polysiloxane;

[0017] S2. 40-45 mL of a silk fibroin solution and 1-2 g of bisaminopropyl terminated polysiloxane are added to a reaction bottle, 0.02-0.04 g of carbodiimide is further added, stirring is performed at room temperature for 10-12 h, then the mixture is poured into a dialysis bag, and dialysis is performed in a distillation water for 3 d to obtain the modified silk fibroin.

[0018] Further, the use amount ratio of octamethylcyclotetrasiloxane, 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane and tetramethylammonium hydroxide in the S1 is 20-24g:19.8-24.6g:1.31-1.36g.

[0019] Further, the preparation method of the mortar containing the nanomaterial is as follows: the cement, fly ash, polycarboxylate superplasticizer, hydroxypropyl methyl cellulose, nanomaterial and modified silk fibroin are added into a stirrer, stirred for 2-3min, then water is added, and stirred for 50-60s to obtain the mortar containing the nanomaterial.

[0020] Beneficial technical effects

[0021] The modified cubic nanometer calcium carbonate and the modified nanometer silicon dioxide are compounded in the application, the cubic nanometer calcium carbonate forms a uniform "skeleton support" in the mortar, and fills the small pores between the cement hydration products; the nanometer silicon dioxide can have a secondary reaction with the calcium hydroxide generated by the cement hydration to generate more dense hydrated calcium silicate, and the two can realize the "physical filling" effect in cooperation, so that the internal structure of the mortar is more dense, and the mechanical effect is improved.

[0022] The nanometer silicon dioxide is modified by gamma-aminopropyl triethoxysilane in the application, the organic groups are introduced on the surface of the nanometer particles by the silane coupling agent, and the agglomeration is reduced; the nanometer calcium carbonate is modified by fumaric acid, sodium stearate and palmitic acid, the carboxyl groups of the three organic acids are combined with the calcium ions on the surface of the calcium carbonate to form a hydrophobic coating layer, and the modified agent is uniformly adsorbed through ultrasonic treatment, so that the dispersion stability of the nanometer particles in the mortar is significantly improved; the modified silk fibroin in the mortar is used as an organic modifier, the amino groups on the molecular chain of the modified silk fibroin form hydrogen bonds and chemical bonds with the modified groups (amino groups and carboxyl groups) on the surface of the nanometer material and the hydroxyl groups of the cement hydration products, so that the problem of weak interface bonding of the traditional organic-inorganic composite material is solved, the nanometer particles are more uniformly dispersed in the mortar, the nanometer particles can "pin" the crack tip when the crack of the mortar occurs, the crack propagation resistance is increased, the crack propagation is prevented, and the durability is improved.

[0023] The silk fibroin is grafted and modified by the bisaminopropyl terminated polysiloxane in the application, the flexible polysiloxane is introduced into the silk fibroin molecular chain, the stability of the silk fibroin in the alkaline environment is improved, the internal stress in the hardening process of the mortar is relieved by the flexible chain segment of the polysiloxane, the mortar is endowed with good toughness, and the generation and expansion of cracks are inhibited; the synergistic filling effect of the compounded nanometer material effectively solves the problem that the traditional mortar is prone to cracking and falling off during long-term use.

[0024] In summary, the mortar of this invention uses a composite of modified cubic nano-calcium carbonate and modified nano-silica as nanomaterials. After specific modification treatment, the dispersibility of both is significantly improved, avoiding the problem of easy agglomeration of single nanomaterials. The nanoparticles optimize the internal pore structure of the mortar through a filling effect, forming a dense bond with cement hydration products. Simultaneously, the introduction of modified silk fibroin enhances the bonding force between components, synergistically improving the mechanical properties of the mortar. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention are described clearly and completely. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] The viscosity of hydroxypropyl methylcellulose is Fly ash is classified as Grade II.

[0027] Preparation method of silk fibroin solution: Weigh 10g of silkworm cocoons and boil them in 4L of 0.05mol / L sodium carbonate aqueous solution for 30min. After removing them, repeat the above steps twice. Wash the boiled silkworm cocoons with deionized water and dry them to obtain degummed silk. Immerse 5.2g of degummed silk in about 75ml of calcium chloride-ethanol-water (molar ratio of 1:2:8) solution and stir at 70℃ for 4h. After cooling, centrifuge at room temperature for 6min to remove insoluble impurities. Place the dissolved silk fibroin solution in a dialysis bag with a molecular weight cutoff of 3500 and dialyze it in deionized water at 4℃ for 3d.

[0028] Example 1

[0029] A mortar containing nanomaterials comprises the following weight components: 70 parts by weight of cement, 8 parts by weight of fly ash, 0.4 parts by weight of polycarboxylate superplasticizer, 0.4 parts by weight of hydroxypropyl methylcellulose, 1 part by weight of nanomaterials, 2 parts by weight of modified silk fibroin, and 40 parts by weight of water.

[0030] The nanomaterial comprises the following weight components: 0.5 parts by weight of modified cubic nano-calcium carbonate and 0.5 parts by weight of modified nano-silica.

[0031] The preparation method of the modified nanometer silicon dioxide is as follows: 45 mL of anhydrous ethanol and 15 mL of deionized water are added into a reactor to prepare a solution, then 1 g of nanometer silicon dioxide is added into the solution, ultrasonic treatment is conducted for 35 min, then 0.04 g of γ-aminopropyl triethoxysilane is added into the solution, hydrochloric acid is used to adjust the pH of the system to 4, reflux reaction is conducted at 45℃ for 1 h, after the reaction is completed, centrifugation, washing and drying are conducted, and the modified nanometer silicon dioxide is obtained.

[0032] The preparation method of the modified cubic nanometer calcium carbonate is as follows:

[0033] a. 2 g of Ca(OH)2 is placed in a high gravity micro-interface reactor, a circulating pump and a cooling device are turned on, when the reaction temperature reaches 25℃, a CO2 gas flow meter is opened, the volume flow rate is set to 3 m 3 / h (standard condition) until the reaction is completed when the pH is 7, then the flow meter and the circulating pump are turned off, and the nanometer calcium carbonate is obtained;

[0034] b. 0.02 g of fumaric acid, 0.031 g of sodium stearate and 0.02 g of palmitic acid are added into 8 mL of an ethanol solvent, ultrasonic treatment is conducted for 10 min, the mixture is uniformly mixed to obtain a mixed solution, then the mixed solution is added into 1 g of nanometer calcium carbonate, reaction is conducted at 65℃ for 40 min, after the reaction is completed, filtration is conducted, and the modified cubic nanometer calcium carbonate is obtained after drying in an oven.

[0035] The preparation method of the modified silk fibroin is as follows:

[0036] S1. 20 g of octamethylcyclotetrasiloxane, 19.8 g of 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane, and 1.31 g of tetramethylammonium hydroxide are added into a reaction bottle, stirring is conducted under the protection of nitrogen, heating is conducted to 85℃, reaction is conducted for 3 h, then the temperature is increased to 135℃, reaction is continued for 1 h, after the reaction is completed, vacuum is pumped by a vacuum pump, and reduced pressure distillation is conducted, so as to obtain bisaminopropyl terminated polysiloxane;

[0037] S2. 40 mL of a silk fibroin solution and 1 g of bisaminopropyl terminated polysiloxane are added into a reaction bottle, then 0.02 g of carbodiimide is added, stirring is conducted at room temperature for 10 h, then the mixture is poured into a dialysis bag, and dialysis is conducted in distilled water for 3 d by using a stirrer, so as to obtain modified silk fibroin.

[0038] The preparation method of the nanometer material-containing mortar is as follows: cement, fly ash, polycarboxylic acid water reducing agent, hydroxypropyl methyl cellulose, nanometer material and modified silk fibroin are added into a stirrer, stirring is conducted for 2 min, then water is added, and stirring is conducted for 50 s, so as to obtain the nanometer material-containing mortar.

[0039] Example 2

[0040] A mortar containing nanomaterials, comprising the following components by weight: 80 parts by weight of cement, 12 parts by weight of fly ash, 0.5 parts by weight of polycarboxylic acid water reducer, 0.6 parts by weight of hydroxypropyl methyl cellulose, 2 parts by weight of nanomaterials, 3 parts by weight of modified silk fibroin, 50 parts by weight of water.

[0041] The nanomaterials comprise the following components by weight: 1 part by weight of modified cubic nanometer calcium carbonate, 1 part by weight of modified nanometer silicon dioxide.

[0042] The preparation method of the modified nanometer silicon dioxide is: 45 mL of anhydrous ethanol and 15 mL of deionized water are added to a reactor to prepare a solution, then 2 g of nanometer silicon dioxide is added, ultrasonic treatment is performed for 40 min, then 0.08 g of γ-aminopropyl triethoxysilane is added, and the system pH is adjusted to 4 with hydrochloric acid, and reflux reaction is performed at 50℃ for 2 h, after the reaction is completed, centrifugation, washing and drying are performed to obtain the modified nanometer silicon dioxide.

[0043] The preparation method of the modified cubic nanometer calcium carbonate is:

[0044] a. 3 g of Ca(OH)2 is placed in a high gravity micro-interface reactor, the circulating pump and cooling device are turned on, when the reaction temperature reaches 25℃, the CO2 gas flow meter is opened, the volume flow rate is set to 3 m 3 / h (standard condition) until the reaction endpoint pH=7, the reaction is completed, the flow meter and circulating pump are turned off, and the nanometer calcium carbonate is obtained;

[0045] b. 0.03 g of fumaric acid, 0.035 g of sodium stearate, and 0.036 g of palmitic acid are added to 10 mL of ethanol solvent, ultrasonic treatment is performed for 15 min, the mixture is uniformly mixed to obtain a mixed solution; then the mixed solution is added to 1.8 g of nanometer calcium carbonate, and reaction is performed at 70℃ for 45 min, after the reaction is completed, filtration is performed, and drying is performed in an oven to obtain the modified cubic nanometer calcium carbonate.

[0046] The preparation method of the modified silk fibroin is:

[0047] S1. 24 g of octamethylcyclotetrasiloxane, 24.6 g of 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane, and 1.36 g of tetramethylammonium hydroxide are added to a reaction bottle, stirring is performed under nitrogen protection, heating is performed to 90℃, reaction is performed for 4 h, then the temperature is increased to 140℃, and reaction is continued for 1.5 h, after the end, vacuum is pumped by a vacuum pump, and reduced pressure distillation is performed to obtain bisaminopropyl terminated polysiloxane;

[0048] S2. 45 mL of the fibroin protein solution and 2 g of bis-aminopropyl terminated polysiloxane were added to a reaction bottle, 0.04 g of carbodiimide was added, and after stirring at room temperature for 12 h, the mixture was poured into a dialysis bag and dialyzed in a distillation water for 3 d to obtain the modified fibroin protein.

[0049] The preparation method of the mortar containing the nanomaterial is as follows: cement, fly ash, polycarboxylate superplasticizer, hydroxypropyl methyl cellulose, nanomaterial, and modified fibroin protein are added to a stirrer, stirred for 3 min, then water is added, and stirred for 60 s to obtain the mortar containing the nanomaterial.

[0050] Example 3

[0051] A mortar containing a nanomaterial, comprising the following components by weight: 75 parts by weight of cement, 10 parts by weight of fly ash, 0.45 parts by weight of polycarboxylate superplasticizer, 0.5 parts by weight of hydroxypropyl methyl cellulose, 1.5 parts by weight of nanomaterial, 2.5 parts by weight of modified fibroin protein, and 45 parts by weight of water.

[0052] The nanomaterial comprises the following components by weight: 0.7 parts by weight of modified cubic-shaped nanometer calcium carbonate, and 0.8 parts by weight of modified nanometer silicon dioxide.

[0053] The preparation method of the modified nanometer silicon dioxide is as follows: 45 mL of anhydrous ethanol and 15 mL of deionized water are added to a reactor to prepare a solution, then 1.5 g of nanometer silicon dioxide is added, ultrasonic treatment is performed for 38 min, then 0.06 g of γ-aminopropyl triethoxysilane is added, the pH of the system is adjusted to 4 with hydrochloric acid, and reflux reaction is performed at 47℃ for 1 h, after the reaction is completed, centrifugation, washing, and drying are performed to obtain the modified nanometer silicon dioxide.

[0054] The preparation method of the modified cubic-shaped nanometer calcium carbonate is as follows:

[0055] a. 2.5 g of Ca(OH)2 is placed in a high gravity micro-interface reactor, the circulating pump and cooling device are turned on, when the reaction temperature reaches 25℃, the CO2 gas flow meter is opened, the volume flow rate is set to 3 m 3 / h (standard condition) until the reaction endpoint pH=7, the flow meter and circulating pump are turned off, and the nanometer calcium carbonate is obtained;

[0056] b. 0.025 g of fumaric acid, 0.032 g of sodium stearate, and 0.02 g of palmitic acid are added to 10 mL of an ethanol solvent, ultrasonic treatment is performed for 15 min, the mixture is uniformly mixed to obtain a mixed solution; then the mixed solution is added to 1.5 g of nanometer calcium carbonate, and reaction is performed at 65℃ for 43 min, after the reaction is completed, filtration is performed, and drying is performed in an oven to obtain the modified cubic-shaped nanometer calcium carbonate.

[0057] The preparation method of the modified silk fibroin is:

[0058] S1. 22 g of octamethylcyclotetrasiloxane, 22.4 g of 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane, 1.3 g of tetramethylammonium hydroxide were added into a reaction bottle, and stirred and heated to 90℃ under nitrogen protection for 4 h, and then heated to 140℃ for 1 h, and then vacuumized by a vacuum pump, and distilled under reduced pressure to obtain bisaminopropyl-terminated polysiloxane;

[0059] S2. 42 mL of a silk fibroin solution and 1.5 g of bisaminopropyl-terminated polysiloxane were added into a reaction bottle, and 0.03 g of carbodiimide was further added, and stirred at room temperature for 11 h, and then poured into a dialysis bag, and dialyzed in distilled water for 3 d on a stirrer to obtain modified silk fibroin.

[0060] The preparation method of the mortar containing nanomaterials is that cement, fly ash, polycarboxylate superplasticizer, hydroxypropyl methyl cellulose, nanomaterials, and modified silk fibroin are added into a stirrer, stirred for 2.5 min, and then water is added and stirred for 60 s to obtain the mortar containing nanomaterials.

[0061] Example 4

[0062] A mortar containing nanomaterials comprises the following components in parts by weight: 70 parts by weight of cement, 8 parts by weight of fly ash, 0.4 parts by weight of polycarboxylate superplasticizer, 0.4 parts by weight of hydroxypropyl methyl cellulose, 1 part by weight of nanomaterials, 2 parts by weight of modified silk fibroin, and 40 parts by weight of water.

[0063] The nanomaterials comprise the following components in parts by weight: 0.5 parts by weight of modified cubic-shaped nanometer calcium carbonate, and 0.5 parts by weight of modified nanometer silicon dioxide.

[0064] The preparation method of the modified nanometer silicon dioxide is that 45 mL of anhydrous ethanol and 15 mL of deionized water are added into a reactor to prepare a solution, 1 g of nanometer silicon dioxide is added into the solution, ultrasonic treatment is performed for 35 min, then 0.04 g of γ-aminopropyl triethoxysilane is added into the solution, hydrochloric acid is used to adjust the pH of the system to 4, and reflux reaction is performed at 45℃ for 1 h, after the reaction is completed, centrifugation, washing and drying are performed to obtain the modified nanometer silicon dioxide.

[0065] The preparation method of the modified cubic-shaped nanometer calcium carbonate is:

[0066] a. 3 g of Ca(OH)2 is placed in a high gravity micro-interface reactor, a circulating pump and a cooling device are turned on, when the reaction temperature reaches 25℃, a CO2 gas flow meter is opened, and the volume flow rate is set to 3 m 3until the reaction ends at pH=7, then turn off the flow meter and the circulating pump, and the nanometer calcium carbonate is obtained;

[0067] b. 0.03 g fumaric acid, 0.035 g sodium stearate, and 0.036 g palmitic acid are added into 10 mL of an ethanol solvent, and ultrasonic treatment is performed for 15 min to obtain a mixture. Then, the mixture is added into 1.8 g of the nanometer calcium carbonate, and reaction is performed at 70°C for 45 min. After the reaction ends, filtration is performed, and the modified cubic nanometer calcium carbonate is obtained after drying in an oven.

[0068] The preparation method of the modified silk fibroin is as follows:

[0069] S1. 22 g of octamethylcyclotetrasiloxane, 22.4 g of 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane, and 1.3 g of tetramethylammonium hydroxide are added into a reaction bottle. Under nitrogen protection, stirring is performed, and heating is performed to 90°C. Reaction is performed for 4 h, and then temperature is increased to 140°C. Reaction is continuously performed for 1 h. After the reaction ends, vacuum is extracted by a vacuum pump, and reduced pressure distillation is performed to obtain bisaminopropyl-terminated polysiloxane.

[0070] S2. 42 mL of a silk fibroin solution and 1.5 g of the bisaminopropyl-terminated polysiloxane are added into a reaction bottle. Then, 0.03 g of carbodiimide is added. After stirring at room temperature for 11 h, the mixture is poured into a dialysis bag, and dialysis is performed in distilled water for 3 d to obtain the modified silk fibroin.

[0071] The preparation method of the nanometer material-containing mortar is as follows: cement, fly ash, polycarboxylic acid water reducer, hydroxypropyl methyl cellulose, nanometer material, and modified silk fibroin are added into a stirrer, and stirring is performed for 2.5 min. Then, water is added, and stirring is performed for 60 s to obtain the nanometer material-containing mortar.

[0072] Comparative Example 1

[0073] The difference between the present comparative example and Example 4 is that nanometer calcium carbonate is used instead of the modified cubic nanometer calcium carbonate.

[0074] Comparative Example 2

[0075] The difference between the present comparative example and Example 4 is that nanometer silicon dioxide is used instead of the modified nanometer silicon dioxide.

[0076] Comparative Example 3

[0077] The difference between the present comparative example and Example 4 is that a silk fibroin solution is used instead of the modified silk fibroin.

[0078] The 14d tensile bonding properties and 28d compressive strength of the mortar of each example and each comparative example were detected according to JGJ / T70-2009 "Standard for Testing Methods of Basic Properties of Building Mortar". The cracking index of the mortar of each example and each comparative example was detected according to JC / T951-2005 "Testing Method for Anti-cracking Properties of Cement Mortar".

[0079] Table 1: Mechanical property test.

[0080] Item 14d tensile bond properties (MPa) 28d compressive strength (MPa) cracking index (mm) Example 1 0.88 47.6 165 Example 2 0.95 48.9 168 Example 3 0.87 49.1 162 Example 4 0.84 45.2 158 Comparative Example 1 0.62 41.6 183 Comparative Example 2 0.60 40.8 187 Comparative Example 3 0.64 42.3 186

[0081] As shown in Table 1, the examples 1-4 have better mechanical effect and anti-cracking performance compared with the comparative examples 1-3. The comparative examples 1-3 break the synergistic system of "modified nanomaterial + modified silk fibroin" in the examples. The core advantage of the example 4 is that the modified nanometer calcium carbonate (skeleton support) + modified nanometer silicon dioxide (secondary reaction) + modified silk fibroin (interface bonding and internal stress relief) synergistically form a complete performance system of "dense structure + strong bonding + anti-cracking buffer". The comparative examples 1-3 respectively weaken one of the key links. The comparative example 1 weakens the "skeleton support", the comparative example 2 weakens the "secondary reaction densification", and the comparative example 3 weakens the "interface bonding and stress relief", which finally leads to the decline of the overall performance.

[0082] It should be noted that in this document, the terms "comprising", "containing", or any other similar term are intended to encompass non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or inherent to such a process, method, article or device. Without more limitations, the element defined by the statement "including a" does not exclude the presence of another identical element in the process, method, article or device including the element.

[0083] The above examples are only used to illustrate the technical solutions of the present application, but not limit it; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that they can still modify the technical solutions recorded in the foregoing examples, or make equivalent replacement for part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

[0084] Those skilled in the art should understand that the above only describes some specific embodiments of the present application, but not all embodiments.

Claims

1. A nanomaterial-containing mortar, characterized by, It comprises the following weight components: 70-80 parts by weight of cement, 8-12 parts by weight of fly ash, 0.4-0.5 parts by weight of polycarboxylic acid water reducer, 0.4-0.6 parts by weight of hydroxypropyl methyl cellulose, 1-2 parts by weight of nanomaterial, 2-3 parts by weight of modified silk fibroin, and 40-50 parts by weight of water.

2. Nanomaterial-containing mortar according to claim 1, characterized in that The nanomaterial comprises the following weight components: 0.5-1 parts by weight of modified cubic nanometer calcium carbonate, and 0.5-1 parts by weight of modified nanometer silicon dioxide. The preparation method of the modified nanometer silicon dioxide is: 45 mL of anhydrous ethanol and 15 mL of deionized water are added to a reactor to prepare a solution, then 1-2 g of nanometer silicon dioxide is added, ultrasonic treatment is performed for 35-40 min, then 0.04-0.08 g of γ-aminopropyl triethoxysilane is added, the system pH is adjusted to 4 with hydrochloric acid, and reflux reaction is performed at 45-50°C for 1-2 h, after the reaction is completed, centrifugation, washing and drying are performed to obtain the modified nanometer silicon dioxide.

3. Nanomaterial-containing mortar according to claim 2, characterized in that The preparation method of the modified cubic nanometer calcium carbonate is: a. Take 2-3 g of Ca(OH)2 and place it in a high gravity micro-interface reactor. Turn on the circulating pump and cooling device. When the reaction temperature reaches 25°C, open the CO2 gas flow meter and set the volumetric flow rate to 3 m 3 / h until the reaction endpoint pH = 7, the reaction is complete, turn off the flow meter and circulating pump, and obtain nano calcium carbonate; b.Fumaric acid, sodium stearate and palmitic acid are added to an ethanol solvent, ultrasonic treatment is performed for 10-15 min, and mixing is uniformly performed to obtain a mixed solution; then the mixed solution is added to 1-1.8 g of nanometer calcium carbonate, reaction is performed at 65-70°C, after the reaction is completed, filtration is performed, and drying is performed in an oven to obtain the modified cubic nanometer calcium carbonate.

4. Nanomaterial-containing mortar according to claim 3, characterized in that The amount ratio of fumaric acid, sodium stearate, palmitic acid and ethanol in step b is 0.02-0.03 g: 0.031-0.035 g: 0.02-0.036 g: 8-10 mL.

5. The nanomaterial-containing mortar according to claim 3, characterized in that, The reaction time in step b is 40-45 min.

6. The nanomaterial-containing mortar of claim 1, wherein, The preparation method of the modified silk fibroin is: S1. Octamethylcyclotetrasiloxane, 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane and tetramethylammonium hydroxide are added to a reaction bottle, stirring is performed under nitrogen protection, heating is performed to 85-90°C, reaction is performed for 3-4 h, then the temperature is raised to 135-140°C, and reaction is continued for 1-1.5 h, after the reaction is completed, vacuum is pumped, and reduced pressure distillation is performed to obtain bisaminopropyl terminated polysiloxane; S2. 40-45 mL of a silk fibroin solution and 1-2 g of bisaminopropyl terminated polysiloxane are added to a reaction bottle, 0.02-0.04 g of carbodiimide is added, stirring is performed at room temperature for 10-12 h, then the mixture is poured into a dialysis bag, and dialysis is performed in a stirrer with distilled water for 3 d to obtain the modified silk fibroin.

7. Nanomaterial-containing mortar according to claim 6, characterized in that The amount ratio of octamethylcyclotetrasiloxane, 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane and tetramethylammonium hydroxide in S1 is 20-24 g: 19.8-24.6 g: 1.31-1.36 g.

8. A method for the production of a nanomaterial-containing mortar according to any one of claims 1 to 7, characterized in that, The preparation method of the nanomaterial-containing mortar is: cement, fly ash, polycarboxylic acid water reducer, hydroxypropyl methyl cellulose, nanomaterial and modified silk fibroin are added to a stirrer, stirring is performed for 2-3 min, then water is added, and stirring is performed for 50-60 s to obtain the nanomaterial-containing mortar.