Nanocomposite hybrid activator for high glass phase building materials and preparation method thereof

Abstract

The present invention relates to the technical field of building materials such as slag and cement. Specifically, a nanocomposite hybrid activator for high-glass phase building materials and its preparation method are disclosed. The activator is composed of 45-55 parts by weight of modified water glass, 4-6 parts of nano-ZnO, 8-12 parts of an organosilane coupling agent, 3-5 parts of a bio-based corrosion inhibitor enhancer, and the remainder being deionized water. This invention pioneers a "photocatalytic bond-breaking, ion-intelligent gating, topological epitaxial growth" ordered excitation technology, overcoming the problems of low excitation rates associated with traditional purely chemical excitation, resulting in insufficient solidification strength and prone to cracking. Furthermore, it fundamentally avoids the serial deterioration effects caused by high alkalinity.

Description

Technical Field

[0001] The present invention relates to the technical field of building materials such as slag and cement, in particular to a composition for high-glass phase building materials, and specifically to a nano-composite hybrid activator for high-glass phase building materials and a preparation method thereof. Background Art

[0002] Cement, an indispensable building material, is in high demand. Existing cements are mostly high in cement clinker. Because cement clinker primarily consists of tricalcium silicate (C3S) and dicalcium silicate (C2S), it is highly reactive and can solidify directly when mixed with water to form concrete. However, the production of cement clinker requires heating limestone (CaCO3) to approximately 1450°C. This process generates two major carbon emissions: fuel combustion and limestone decomposition. This conflicts with current sustainable development strategies for energy conservation and emission reduction, including waste resource utilization, performance optimization, and application-specific requirements. Therefore, there is a need to explore other more environmentally friendly and cost-effective cement-based materials.

[0003] As suitable low-cost cement base materials, slag, fly ash and other materials are negative products or waste, and their production volume is large. Therefore, using them as new cement base materials is a good choice. This can not only achieve the reuse of resources by turning waste into treasure, but also greatly reduce the high carbon emissions caused by cement clinker production, which leads to environmental pollution. However, simply using slag, fly ash and other materials as cement base materials also has problems. This is because slag and fly ash cannot naturally react with water to produce gel. Therefore, it is necessary to develop a high-performance activator to activate the hydration of high-glass phase environmentally friendly cement base materials, so as to achieve the purpose of replacing traditional cement clinker, achieving solid waste utilization, energy conservation and emission reduction. There are already activators in the prior art, but most of them are base-based. For example, CN115818994A discloses a silica fume-based alkaline activator and a preparation method. It mainly produces a hydration reaction by directly adding OH⁻ / SO4²⁻ to the substrate using a single chemical dissolution method. There is a high alkali risk, and the use of functional additives such as chromate is toxic. At the same time, the activation rate for slag reactivity is not high enough. Most of the existing activators are in the activation range of 50%-70%, which means that some substrates are not effectively activated, resulting in unadjustable setting time, relatively low compressive strength, and easy cracking. Summary of the Invention

[0004] In order to solve the problem of high alkali risk mentioned in the background technology that the existing activators are mainly based on bases, which are prone to high alkali risks. The main manifestation is that the alkali silicate gel generated by the reaction of silica in the substrate aggregate with alkali ions absorbs water and expands, resulting in a network of cracks in the concrete structure after solidification, leading to strength loss and shortened structural life; the nano-composite hybrid activator for high glass phase building materials provided in the present application and the preparation method thereof use nano-composite organic-inorganic hybrid activators. Compared with the existing base activators, in terms of materials, it abandons the traditional single chemical dissolution excitation principle and adopts a more environmentally friendly and effective "photo-electro-chemical" three-mode synergy, using ZnO@C for photocatalytic bond breaking, phytic acid-chitosan self-assembled microspheres for ion gating, and γ-glycidyloxypropyltrimethoxysilane as a guide to achieve topological epitaxial growth, multi-directionally stimulating material activity. Compared with the existing single chemical dissolution, the excitation rate is significantly increased, so that the overall proportion of the substrate participating in the hydration and adhesion reaction is increased, the overall utilization efficiency of the material is improved, and the structural strength after solidification is enhanced. The present invention enables the directed assembly of phosphorus-zinc-doped gels, achieving atomic-level structural design to suppress or reduce defects. It also uses a silane coupling agent to construct a covalent Si-O interface, enhancing interfacial bonding. Laminar mixing in a microfluidic chip replaces existing mechanical stirring to address the problem of uneven mixing. Furthermore, electrostatic spraying of self-assembled microspheres effectively controls the assembly structure, addressing the existing uncontrolled spontaneous assembly method. Energy consumption is significantly reduced by combining airflow milling with ultrasound to replace existing high-energy ball milling methods.

[0005] In order to achieve the above objectives, the technical solutions adopted in this application are:

[0006] The invention provides a nano composite hybrid activator for high glass phase building materials, which is composed of 45-55 parts by weight of modified water glass, 4-6 parts by weight of nano ZnO, 8-12 parts by weight of an organic silane coupling agent, 3-5 parts by weight of a bio-based corrosion inhibitor and enhancer, and the remainder being deionized water.

[0007] Preferably, the modified water glass is a nano-silica sol with a modulus of 1.8, the particle size of nano-ZnO is 20nm-30nm, the organic silane coupling agent is γ-glycidyloxypropyltrimethoxysilane, and the bio-based corrosion inhibitor is a sodium phytate aqueous solution.

[0008] Preferably, the nano ZnO is replaced by ZnO@biochar core-shell structure, with a mass fraction of 4 parts; the bio-based corrosion inhibitor is phytic acid-chitosan self-assembled microspheres, with a mass fraction of 3 parts; and the deionized water is replaced by alkaline electrolyzed water, with a pH of 11.5.

[0009] The present invention provides a method for preparing an activator for preparing the above-mentioned nanocomposite hybrid activator for high glass phase building materials, comprising the following steps:

[0010] Step STP100, preparing nano ZnO suspension

[0011] Step STP110, pre-dispersion, adding nano ZnO powder to 30 g of deionized water, mechanically stirring at 2000 rpm for 10 minutes at 25° C. to obtain a pre-dispersion liquid;

[0012] Step STP120, adding a dispersant, adding a PAA solution to the pre-dispersion liquid: 0.5 g PAA dissolved in 15 g water, ultrasonically treating: 40 kHz, 500 W, for 20 min, with the temperature controlled at 10°C-40°C throughout the process, to obtain a dispersion;

[0013] Step STP130, nano-grinding, transferring the dispersion obtained in step STP120 to a planetary ball mill for grinding, wherein the zirconia balls are φ1 mm, the ball-to-material ratio is 5:1, the rotation speed is 300 rpm, the grinding time is 2 h to 3 h, and the product index parameters are controlled to be: D50 particle size ≤50 nm, Zeta potential ≤-35 mV, pH = 9.0, to obtain a nano-ZnO suspension;

[0014] Step STP200, modified water glass pretreatment

[0015] Step STP210, modulus adjustment, adding 10 g of deionized water to 50 g of water glass for dilution, and stirring at 500 rpm for 10 min until uniform;

[0016] Step STP220, nano-silica sol conversion, adding 0.5 g of ammonia water to the mixture of step STP210, and reacting in a 60° C. water bath for 3 h with magnetic stirring at 300 rpm; the sol particle size is 5-10 nm, and modified water glass is obtained;

[0017] Step STP300, silane hydrolysis activation

[0018] Step STP310, preparing the hydrolyzate: mixing 16 g of ethanol, 4 g of water, and 0.1 g of acetic acid at 25° C., and magnetically stirring for 5 min;

[0019] Step STP320, silane hydrolysis, γ-glycidyloxypropyltrimethoxysilane was added dropwise to the mixture, and stirred at 40°C for 2 hours, pH = 4.0 ± 0.2;

[0020] Step STP330, controlling the degree of hydrolysis, monitoring by FTIR, until the 1080 cm⁻¹Si-OC peak disappears and the 880 cm⁻¹Si-OH peak appears, to obtain a silane hydrolyzate;

[0021] Step STP400, preparing a sodium phytate solution: adding 5 g of sodium phytate with a purity greater than 90% to 15 g of deionized water at 60° C., dissolving the solution by ultrasonication at 100 W for 10 minutes, and then filtering the solution through a 0.22 μm membrane to remove insoluble matter, thereby obtaining a sodium phytate solution;

[0022] Step STP500, gradient mixing and maturation,

[0023] Step STP510, stirring the nano ZnO suspension obtained in step STP100 and the modified water glass obtained in step STP200 at 25° C. and 800 rpm for 15 minutes to obtain a first gradient mixed solution;

[0024] Step STP520, adding the silane hydrolyzate obtained in step STP300 to the first gradient mixed solution, and maintaining high shear stirring at 40° C. and 1200 rpm for 30 minutes to obtain a second gradient mixed solution;

[0025] Step STP530, adding the sodium phytate solution obtained in step STP400 dropwise to the second gradient mixed solution, and slowly stirring at 25° C. and 500 rpm for 10 minutes to obtain a third gradient mixed solution;

[0026] Step STP540, adding deionized water to the third gradient mixed solution to make 100 g, and vacuum degassing under -0.08 MPa for 5 minutes to obtain a fourth gradient mixed solution;

[0027] Step STP550: transfer the fourth gradient mixed solution to a closed reactor and allow to stand at a constant temperature of 45° C. for 24 hours to obtain a nanocomposite hybrid activator.

[0028] In order to further optimize the preparation process, preferably, the step of preparing ZnO@biochar core-shell structure and phytic acid-chitosan self-assembled microspheres is also included to obtain the nanocomposite hybrid activator, wherein

[0029] The steps of preparing the ZnO@biochar core-shell structure include:

[0030] Step STP10, preparation of raw materials: cracking rice husks under oxygen-limited conditions at 500°C to obtain biochar with a specific surface area of ​​800 m² / g; simultaneously, preparing a 0.5 mol / L Zn(NO3)2 solution for later use;

[0031] Step STP20, impregnation, immersing the biochar in a Zn(NO3)2 solution at a liquid-to-solid ratio of 10:1 and ultrasonically oscillating at a frequency of 40 kHz for 1 h;

[0032] Step STP30, calcination, heating the mixture to 400°C at a heating rate of 5°C / min under N2 protection and keeping the temperature for 2 hours;

[0033] Step STP40, reduction, and then placing the calcined product in a mixture of H2 and Ar with a H2 content of 5% at a constant temperature of 300°C for 1 hour to obtain a ZnO@biochar core-shell structure;

[0034] The steps of preparing the phytic acid-chitosan self-assembled microspheres include:

[0035] Step STP01, preparation of raw materials, using chitosan with a deacetylation degree of 90%, a 2 wt% acetic acid solution and a 50 wt% aqueous solution of phytic acid for standby use;

[0036] Step STP02, electrospraying, injecting the chitosan solution at the positive electrode and the phytic acid at the negative electrode into an electrostatic spray device for spraying, wherein the voltage is +15 kV and -10 kV respectively, the receiving distance is 15 cm, and the spray temperature is 25°C;

[0037] Step STP03, self-assembly, the droplets with opposite charges collide to form phytic acid-chitosan composite microspheres with a particle size of 1-2 μm.

[0038] More preferably, the method further includes a step of using a microfluidic chip to continuously mix and realize gradient mixing, which is used to replace step STP500 in claim 4, specifically comprising:

[0039] A Y-shaped channel microfluidic chip with a main channel width of 200 μm was used for gradient mixing, wherein

[0040] Inlet 1 of the microfluidic chip is the modified water glass and ZnO@C suspension obtained in step STP220, and inlet 2 of the microfluidic chip is the silane hydrolyzate and phytic acid microsphere dispersion obtained in step STP330, which are mixed according to the flow rate ratio of 3:1, total flow rate of 10 mL / min, mixing temperature of 30°C, and residence time of 60 s. The ZnO@C suspension in inlet 1 is obtained by adding the ZnO@biochar core-shell structure obtained in step STP40 to deionized water containing 0.5 wt% PAA dispersant at a solid-liquid ratio of 1:9, and then simultaneously performing ultrasonic depolymerization and ball milling-assisted treatment to obtain the ZnO@C suspension.

[0041] The phytic acid microsphere dispersion at inlet 2 was prepared by adding deionized water to the phytic acid-chitosan composite microspheres obtained in step STP03 and centrifuging at 8000 rpm for 10 min. After repeating this process three times, the precipitated microspheres were mixed with deionized water and ultrasonically dispersed at 40 kHz, 200 W for 10 min to obtain a 5 wt% phytic acid microsphere dispersion.

[0042] Still more preferably, the control conditions of the ultrasonic deagglomeration are: frequency 40 kHz, power 500 W, duration 30 min; the control conditions of the ball milling assistance are: grinding with zirconia beads at 300 rpm for 1 h.

[0043] Beneficial effects:

[0044] 1. This invention pioneers the "photocatalytic bond breaking → ion intelligent gating → topological epitaxial growth" ordered excitation technology, breaking through the problems of insufficient solidification strength and easy cracking caused by the low excitation rate of traditional pure chemical excitation; at the same time, it fundamentally avoids the series of degradation effects caused by high alkalinity.

[0045] 2. The present invention uses nano-silica sol to slowly release OH⁻ to replace the degradation effect easily caused by the one-time addition of the existing alkaline activator. At the same time, it combines the biochar porous scaffold to solve the problem that the existing activator without a carrier easily causes nanoparticle agglomeration, so that the active site density can be increased exponentially.

[0046] 3. The present invention adopts microfluidic chip laminar mixing technology in the preparation process to solve the problem of uneven mixing in existing stirring; at the same time, electrostatic spray self-assembly of microspheres is used to effectively control the assembly structure, solving the problem that the existing uncontrolled spontaneous assembly method leads to the lack of guaranteed dispersibility; the present invention also adopts the combination of air flow crushing and ultrasound to replace the existing high-energy ball milling method, which can significantly reduce energy consumption and save more energy and reduce emissions. DETAILED DESCRIPTION

[0047] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the embodiments of the present application will be explained below. At the same time, the technical solutions in the embodiments of the present application will be clearly and completely described. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments.

[0048] Example 1:

[0049] The present embodiment provides a nano-composite hybrid activator for high-glass phase building materials. The high-glass phase building materials refer to materials that have a high glass phase content in the building materials or are mainly composed of glass phases, which are the main effective components for the building materials to produce or achieve their solidification effects. The materials with high glass phase mainly include granulated blast furnace slag, whose glass phase content is greater than 90%; fly ash, which is mainly composed of glass beads, and the glass phase is its main active source, and the main component is silica-alumina glass. Silica ash is almost pure amorphous glassy silicon dioxide; there is also kaolin, an amorphous silicate formed after calcining and dehydroxylation of kaolin. These are all representatives of the main materials of high glass phase as cement building materials. However, although these materials are low-cost and can achieve waste utilization, since the materials are high-glass phase components, they cannot spontaneously undergo hydration reaction after mixing with water to form a gelling material to solidify. Therefore, an activator is needed to destroy or dissolve the structure of the glass phase so that the active components therein, such as Si 4 ⁺, Al³⁺, and Ca²⁺ ions are released and participate in the hydration reaction. The higher the glassy phase content, the more ions are released, and generally the material's activity potential is greater. The greater the degree of activation and the more comprehensive the release of material activity, the stronger the resulting concrete and the greater its crack resistance. The activator provided in this embodiment is used to activate the activity of the above-mentioned high-glass phase materials. It is specifically composed of 45-55 parts by weight of modified water glass, 4-6 parts of nano-ZnO, 8-12 parts of an organosilane coupling agent, 3-5 parts of a bio-based corrosion inhibitor enhancer, and the remainder is deionized water.

[0050] Explanation of the excitation principle: In order to fully explain the excitation principle of the glass phase material by the activator, first, the hydration reaction of the crystalline phase material of the cement material that does not require an activator is briefly explained. As a crystalline phase material that cannot spontaneously undergo hydration reaction with water, for example, traditional cement clinker usually exists in the form of β-type tricalcium silicate, which has a clear crystal structure. The hydration process can be simply described as: C3S dissolution → ion release → formation of calcium silicate hydrate (CSH) and calcium hydroxide (CH). It can be expressed as a chemical equation as follows:

[0051] 2Ca3SiO5+7H2O→3CaO·2SiO2·4H2O(CSH)+3Ca(OH)2

[0052] Among them, CSH gel is the main source of cement strength and determines the overall solidification strength of concrete.

[0053] In this embodiment, since the glass phase hardly undergoes a self-reflective reaction in a conventional aqueous environment, it can be specifically divided into the following three types: the first is quartz glass, which is completely unable to react naturally with water due to the high Si-O bond energy and dense network; the second is soda-lime glass, which may contain a very small amount of Na⁺ after mixing with water, which can be slowly eroded by H⁺ ion exchange, so a very weak microscopic reaction may occur. From a macroscopic point of view, it can be regarded as non-reactive; the third is slag glass phase, which does not react under conventional neutral conditions. If the pH environment is increased, such as by injecting a high concentration of OH⁻ to destroy the structure, a reaction may occur, such as adding an existing base activator, but in a conventional environment, no reaction will occur. The working principle of this embodiment for exciting the above-mentioned glass phase materials is described as follows:

[0054] 1. Modified water glass is the core excitation source, providing high concentration of OH⁻ and soluble silicate SiO4 4 ⁻, destroying the Si-O-Si / Al network in the vitreous body. Nano-silica sol with a particle size of <10 nm can penetrate into the micro-cracks in the vitreous body, increasing the reaction interface. The reaction principle can be expressed as:

[0055] Network depolymerization: Si-O-Si+2OH→Si-OH+¯O-Si;

[0056] Supplement active silicon source: SiO2 (nano) + 2OH¯ → SiO3²¯ + H2O

[0057] 2. Nano zinc oxide ZnO is used as a catalytic enhancer

[0058] Its function is to generate holes h⁺ and electrons e⁻ under light, accelerate the breaking of Si-O bonds on the surface of the glass, and Zn²⁺ participates in the formation of zinc-doped C-(A)-SH gel, thereby improving the early strength.

[0059] 3. Organic silane coupling agent is an interfacial bridging agent

[0060] The function is to form silanol -Si-OH after hydrolysis, which condenses with the hydroxyl groups on the surface of the glass to form an organic-inorganic interface layer, and the epoxy groups undergo ring-opening polymerization to build a flexible cross-linked network and improve brittleness. Its principle can be expressed as follows:

[0061] KH 560 +H2O→(HO)3Si-(CH2)3-O0-CH2-CHO-CH2-hydrolysis

[0062] (HO)3Si¯…HO-Si(vitreous)→→(vitreous)-Si-O-Si¯+H2O-condensation

[0063] Epoxy ring opening → -CH2-CH(OH)-CH2- flexible crosslinking

[0064] 4. Bio-based corrosion inhibitor enhancer

[0065] Its function is to chelate harmful ions: phytate C6H6O 24 P6¹²⁻ chelates Al³⁺ and Fe³⁺ dissolved in the vitreous body, inhibiting delayed ettringite destruction; promoting the densification of C-(A)-SH, and the phosphate groups participate in gel precipitation to form phosphorus-doped nanoparticles, which can be specifically expressed as:

[0066] C6H6O 24 P6 12- + 2 A1 3+ → [Al2(C6H6O 24 P6)]↓ chelate precipitation

[0067] Ca²+ + PO4 3- + SiO4 4- +→ Ca5(PO4)x(SiO4) 1-x (OH) Phosphorus-doped CSH

[0068] 5. Multi-component synergistic mechanism

[0069] The exciter composition provided in this embodiment has multiple synergistic effects, which can be summarized as follows:

[0070] Synergistic effect 1: Nanoparticle synergistic penetration-catalysis, its working mechanism is that nano-SiO2 (water glass carrier) and ZnONPs form a heterojunction, generating Z-type electron transfer under light, and e⁻ jumps from the ZnO conduction band to the SiO2 valence band, improving the redox efficiency and accelerating the disaggregation of the glass.

[0071] Synergistic effect 2: Organic-inorganic interface enhancement. Its working mechanism is that the silane hydrolysis products co-condense with nano-SiO2 to form an inorganic nanocore wrapped in an organic silicon network. This structure is anchored to the glass surface through Si-O-Si bonds. At the same time, the organic chain extends to the liquid phase, attracting Ca²⁺ / Al³⁺ ion enrichment and locally accelerating nucleation.

[0072] Synergistic effect 3: Ion regulation - gel optimization. Its working mechanism is that Zn²⁺ promotes C-(A)-SH nucleation in the early stage and Zn²⁺ replaces Ca²⁺ to improve the degree of gel polymerization; in the later stage, phytate chelates excess Al³⁺ to prevent excessive expansion of AFt. The general reaction formula can be expressed as:

[0073] (Ca, Zn)5(SiO4) 2.5 (PO4) 0.5 (OH) ・n H2O

[0074] A dense phosphorus-zinc doped gel is formed.

[0075] The following uses slag glass as an example to further explain the process of gel excitation in the glass phase of the material using chemical formulas. The main active ingredient of slag glass is: CaAl2Si2O8, so the changes it undergoes under the action of the activator are as follows:

[0076] In the first step, the network dissociation of the material, the reaction between the activator and the active component of slag glass CaAl2Si2O8 is as follows: CaAl2Si2O8 + 8OH¯ → Ca 2+ + 2 Al(OH)4¯ + 2H2SiO4 2- ; The second step is synergistic nucleation under the premise of the intervention of nano / organic components, and its reaction can be expressed as:

[0077] 2H2SiO4 2- +3Ca 2+ + ZnO + KH560 → [Zn-Ca-Si-O] @ Si-(CH2)3-epoxy + 4H + Among them, [Zn-Ca-Si-O]@Si-(CH2)3 represents the generated organic-inorganic hybrid core, which is the key intermediate product for the subsequent gel production. It is also the key to improving the material excitation degree and the strength after solidification, which is different from the existing single chemical reaction. The third step is to achieve gel growth through ion regulation, mainly by the organic-inorganic hybrid core generated in the second step and OH4 - +PO4 3- The reaction generates a gel final product, and the reaction process can be expressed as:

[0078] [Hybrid core]+Al(OH)4 - +PO4 3- →Ca3(Zn0·2)(Si1·8Al0·2O)(PO4) 0.1 (OH) 0.6 ·2H2O.

[0079] At this point, the stimulator provided in this embodiment completely realizes the stimulation of the glass phase material, so that the glass phase in the material can highly participate in the reaction and produce a gel substance for the solidification of the material; thereby, the industry can realize the reuse of industrial waste residues, replace the existing cement clinker, and solve the problems of high cost, high energy consumption, high carbon emissions and other environmental pollution caused by cement clinker production.

[0080] This embodiment adopts a conventional concrete mixing method, and adds 5% of the activator provided in this embodiment to the building material with a slag content of 80%. Standard tests are carried out according to national standards, which can shorten the initial setting time to 45 minutes, achieve a 3-day strength of 15 MPa, and a 28-day compressive strength of 45 MPa, exceeding the strength of the pure slag system of <30 MPa and fully meeting the GB / T 18046-2017 standard.

[0081] The main advantages of this embodiment over the prior art are:

[0082] The nano-SiO2 / ZnO heterojunction significantly increases the reaction rate compared to traditional water glass, which can further improve the strength of concrete after solidification and has a higher excitation rate; secondly, the compressive strength of the phosphorus-zinc doped gel reaches 45 MPa, surpassing the strength of the pure slag system of <30 MPa; furthermore, sodium phytate is used to replace the toxic chromate corrosion inhibitor, with a biodegradation rate of >90%, significantly improving environmental protection; the component ratio provided in this embodiment is fully applicable to systems such as CaO-SiO2-Al2O3 (slag) and CaO-Fe2O3-SiO2 (steel slag), and has wider practicality and compatibility with materials.

[0083] Example 2:

[0084] This embodiment is further optimized and improved on the basis of Example 1. The improvements mainly include that the modified water glass is a nano-silica sol with a modulus of 1.8, the particle size of nano-ZnO is 20nm-30nm, the organic silane coupling agent is γ-glycidyloxypropyltrimethoxysilane, and the bio-based corrosion inhibitor is a sodium phytate aqueous solution.

[0085] Example 3:

[0086] This embodiment is a preferred embodiment based on Examples 1-2. In this embodiment, the nano-ZnO is replaced by a ZnO@biochar core-shell structure, with a mass fraction of 4 parts; the bio-based corrosion inhibitor enhancer is phytic acid-chitosan self-assembled microspheres, with a mass fraction of 3 parts; and the deionized water is replaced by alkaline electrolyzed water, with a pH of 11.5.

[0087] The technical advantages and basis of this optimized example are as follows: the biochar carrier, derived from rice husks, effectively provides a natural porous scaffold, enhancing ZnO dispersion; the carbon surface functional groups (-COOH, -OH) enhance interfacial bonding. The phytic acid-chitosan self-assembled microspheres electrostatically self-assemble chitosan and phytic acid to form sustained-release microspheres, increasing chelation capacity by 2-fold and exhibiting antibacterial properties. Alkaline electrolyzed water, pH 11.5, contains reactive oxygen species, •OH and H2O2, which can pre-spark the glass surface, providing more favorable conditions for subsequent gel formation. The activator provided in this example was subjected to strength testing in the same manner as in Example 1, except that the building material containing 80% slag was replaced with 70% steel slag + 30% slag, and 5% of the activator provided in this example was added. After 28 days of activation, the compressive strength reached 48.5 MPa, significantly exceeding the national standard of ≥32.5. The volume expansion rate was <0.02%, well below the safety threshold of 0.1%. It can be seen from this that the stimulator of this embodiment realizes the integration of excitation-stabilization-enhancement functions based on its special sandwich structure "biochar-ZnO-phytic acid microspheres", and the technical effect is significantly better than the existing base stimulators, and there is no uncontrollable risk of a series of side reactions caused by high alkalinity.

[0088] Example 4:

[0089] The present invention provides a method for preparing an activator, which is used to prepare the nanocomposite hybrid activator for high glass phase building materials described in Example 1 or 2, comprising the following steps:

[0090] Step STP100, preparing nano ZnO suspension

[0091] Step STP110, pre-dispersion, adding nano ZnO powder to 30 g of deionized water, mechanically stirring at 2000 rpm for 10 minutes at 25° C. to obtain a pre-dispersion liquid;

[0092] Step STP120, adding a dispersant, adding a PAA solution to the pre-dispersion liquid: 0.5 g PAA dissolved in 15 g water, ultrasonically treating: 40 kHz, 500 W, for 20 min, with the temperature controlled at 10°C-40°C throughout the process, to obtain a dispersion;

[0093] Step STP130, nano-grinding, transferring the dispersion obtained in step STP120 to a planetary ball mill for grinding, wherein the zirconia balls are φ1 mm, the ball-to-material ratio is 5:1, the rotation speed is 300 rpm, the grinding time is 2 h to 3 h, and the product index parameters are controlled to be: D50 particle size ≤50 nm, Zeta potential ≤-35 mV, pH = 9.0, to obtain a nano-ZnO suspension;

[0094] Step STP200, modified water glass pretreatment

[0095] Step STP210, modulus adjustment, adding 10 g of deionized water to 50 g of water glass for dilution, and stirring at 500 rpm for 10 min until uniform;

[0096] Step STP220, nano-silica sol conversion, adding 0.5 g of ammonia water to the mixture of step STP210, and reacting in a 60° C. water bath for 3 h with magnetic stirring at 300 rpm; the sol particle size is 5-10 nm, and modified water glass is obtained;

[0097] Step STP300, silane hydrolysis activation

[0098] Step STP310, preparing the hydrolyzate: mixing 16 g of ethanol, 4 g of water, and 0.1 g of acetic acid at 25° C., and magnetically stirring for 5 min;

[0099] Step STP320, silane hydrolysis, γ-glycidyloxypropyltrimethoxysilane was added dropwise to the mixture, and stirred at 40°C for 2 hours, pH = 4.0 ± 0.2;

[0100] Step STP330, controlling the degree of hydrolysis, monitoring by FTIR, until the 1080 cm⁻¹Si-OC peak disappears and the 880 cm⁻¹Si-OH peak appears, to obtain a silane hydrolyzate;

[0101] Step STP400, preparing a sodium phytate solution: adding 5 g of sodium phytate with a purity greater than 90% to 15 g of deionized water at 60° C., dissolving the solution by ultrasonication at 100 W for 10 minutes, and then filtering the solution through a 0.22 μm membrane to remove insoluble matter, thereby obtaining a sodium phytate solution;

[0102] Step STP500, gradient mixing and maturation,

[0103] Step STP510, stirring the nano ZnO suspension obtained in step STP100 and the modified water glass obtained in step STP200 at 25° C. and 800 rpm for 15 minutes to obtain a first gradient mixed solution;

[0104] Step STP520, adding the silane hydrolyzate obtained in step STP300 to the first gradient mixed solution, and maintaining high shear stirring at 40° C. and 1200 rpm for 30 minutes to obtain a second gradient mixed solution;

[0105] Step STP530, adding the sodium phytate solution obtained in step STP400 dropwise to the second gradient mixed solution, and slowly stirring at 25° C. and 500 rpm for 10 minutes to obtain a third gradient mixed solution;

[0106] Step STP540, adding deionized water to the third gradient mixed solution to make 100 g, and vacuum degassing under -0.08 MPa for 5 minutes to obtain a fourth gradient mixed solution;

[0107] Step STP550: transfer the fourth gradient mixed solution to a closed reactor and allow to stand at a constant temperature of 45° C. for 24 hours to obtain a nanocomposite hybrid activator.

[0108] Example 5:

[0109] In order to further optimize the preparation process, this embodiment further improves the process steps based on Example 4, specifically including the steps of preparing ZnO@biochar core-shell structure and phytic acid-chitosan self-assembled microspheres to obtain the nanocomposite hybrid activator described in Example 3, wherein

[0110] The steps of preparing the ZnO@biochar core-shell structure include:

[0111] Step STP10, preparation of raw materials: cracking rice husks under oxygen-limited conditions at 500°C to obtain biochar with a specific surface area of ​​800 m² / g; simultaneously, preparing a 0.5 mol / L Zn(NO3)2 solution for later use;

[0112] Step STP20, impregnation, immersing the biochar in a Zn(NO3)2 solution at a liquid-to-solid ratio of 10:1 and ultrasonically oscillating at a frequency of 40 kHz for 1 h;

[0113] Step STP30, calcination, heating the mixture to 400°C at a heating rate of 5°C / min under N2 protection and keeping the temperature for 2 hours;

[0114] Step STP40, reduction, and then placing the calcined product in a mixture of H2 and Ar with a H2 content of 5% at a constant temperature of 300°C for 1 hour to obtain a ZnO@biochar core-shell structure;

[0115] The steps of preparing the phytic acid-chitosan self-assembled microspheres include:

[0116] Step STP01, preparation of raw materials, using chitosan with a deacetylation degree of 90%, a 2 wt% acetic acid solution and a 50 wt% aqueous solution of phytic acid for standby use;

[0117] Step STP02, electrospraying, injecting the chitosan solution at the positive electrode and the phytic acid at the negative electrode into an electrostatic spray device for spraying, wherein the voltage is +15 kV and -10 kV respectively, the receiving distance is 15 cm, and the spray temperature is 25°C;

[0118] Step STP03, self-assembly, the droplets with opposite charges collide to form phytic acid-chitosan composite microspheres with a particle size of 1-2 μm.

[0119] In this embodiment, a step of implementing gradient mixing by continuous mixing using a microfluidic chip is also included, which is used to replace step STP500 in claim 4, and specifically includes:

[0120] A Y-shaped channel microfluidic chip with a main channel width of 200 μm was used for gradient mixing, wherein

[0121] Inlet 1 of the microfluidic chip is the modified water glass and ZnO@C suspension obtained in step STP220, and inlet 2 of the microfluidic chip is the silane hydrolyzate and phytic acid microsphere dispersion obtained in step STP330, which are mixed according to the flow rate ratio of 3:1, total flow rate of 10 mL / min, mixing temperature of 30°C, and residence time of 60 s. The ZnO@C suspension in inlet 1 is obtained by adding the ZnO@biochar core-shell structure obtained in step STP40 to deionized water containing 0.5 wt% PAA dispersant at a solid-liquid ratio of 1:9, and then simultaneously performing ultrasonic depolymerization and ball milling-assisted treatment to obtain the ZnO@C suspension.

[0122] The phytic acid microsphere dispersion at inlet 2 is prepared by adding deionized water to the phytic acid-chitosan composite microspheres obtained in step STP03 and centrifuging at 8000 rpm for 10 minutes. After repeating this process three times, the precipitated microspheres are mixed with deionized water and ultrasonically dispersed at 40 kHz, 200 W for 10 minutes to obtain a 5 wt% phytic acid microsphere dispersion. In addition to the parameters disclosed above in this embodiment, the microfluidic chip can also use an existing PDMS chip customized by Shenzhen Micro-Nano Core, my country, or a MicroLYST-SY200 chip with a 200 μm circular channel pressure range of 0-5 bar produced by Syrris as an alternative. Of course, under the premise of a relatively sufficient cost budget, a microfluidic chip with a stronger pressure resistance, the Fluidic 280Y model produced by Dolomite Microfluidics, with a channel size of 200×200 μm and a pressure resistance of 0-10 bar, can also be selected.

[0123] Still more preferably, the control conditions of the ultrasonic deagglomeration are: frequency 40 kHz, power 500 W, duration 30 min; the control conditions of the ball milling assistance are: grinding with zirconia beads at 300 rpm for 1 h.

[0124] The above description is merely a preferred embodiment of the present application and is not intended to limit the present application. Various modifications and variations are possible for those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. Nanocomposite hybrid activator for high glass phase building materials, characterized by: The invention comprises 45-55 parts by weight of modified water glass, 4-6 parts of nano ZnO, 8-12 parts of silane hydrolyzate, 3-5 parts of a bio-based corrosion inhibitor and enhancer, and the remainder being deionized water; the modified water glass is a nano silica sol with a modulus of 1.8, the particle size of the nano ZnO is 20nm-30nm, the silane hydrolyzate is a hydrolyzate of an organic silane coupling agent, the organic silane coupling agent is γ-glycidyloxypropyltrimethoxysilane, and the bio-based corrosion inhibitor and enhancer is a sodium phytate aqueous solution.

2. The nanocomposite hybrid activator for high glass phase building materials according to claim 1, characterized in that: The nano ZnO was replaced by a ZnO@biochar core-shell structure, with a mass fraction of 4 parts; the bio-based corrosion inhibitor enhancer was phytic acid-chitosan self-assembled microspheres, with a mass fraction of 3 parts; and the deionized water was replaced by alkaline electrolyzed water, with a pH of 11.

5.

3. A method for preparing an activator for preparing the nanocomposite hybrid activator for high glass phase building materials according to claim 1, characterized in that: The steps include: Step STP100, preparing nano ZnO suspension Step STP110, pre-dispersion, adding nano ZnO powder to 30 g of deionized water, mechanically stirring at 2000 rpm for 10 minutes at 25° C. to obtain a pre-dispersion liquid; Step STP120, adding a dispersant, adding a PAA solution to the pre-dispersion liquid: 0.5 g PAA dissolved in 15 g water, ultrasonically treating: 40 kHz, 500 W, for 20 min, with the temperature controlled at 10°C-40°C throughout the process, to obtain a dispersion; Step STP130, nano-grinding, transferring the dispersion obtained in step STP120 to a planetary ball mill for grinding, wherein the zirconia balls are φ1 mm, the ball-to-material ratio is 5:1, the rotation speed is 300 rpm, the grinding time is 2 h to 3 h, and the product index parameters are controlled to be: D50 particle size ≤50 nm, Zeta potential ≤-35 mV, pH = 9.0, to obtain a nano-ZnO suspension; Step STP200, modified water glass pretreatment Step STP210, modulus adjustment, adding 10 g of deionized water to 50 g of water glass for dilution, and stirring at 500 rpm for 10 min until uniform; Step STP220, nano-silica sol conversion, adding 0.5 g of ammonia water to the mixture of step STP210, and reacting in a 60° C. water bath for 3 h with magnetic stirring at 300 rpm; the sol particle size is 5-10 nm, and modified water glass is obtained; Step STP300, silane hydrolysis activation Step STP310, preparing the hydrolyzate: mixing 16 g of ethanol, 4 g of water, and 0.1 g of acetic acid at 25° C., and magnetically stirring for 5 min; Step STP320, silane hydrolysis, γ-glycidyloxypropyltrimethoxysilane was added dropwise to the mixture, and stirred at 40°C for 2 hours, pH = 4.0 ± 0.2; Step STP330, hydrolysis degree control, FTIR monitoring 1080cm -1 The Si-OC peak disappears and the 880cm -1 Si-OH peak is reached, and the silane hydrolyzate is obtained; Step STP400, preparing a sodium phytate solution: adding 5 g of sodium phytate with a purity greater than 90% to 15 g of deionized water at 60° C., dissolving the solution by ultrasonication at 100 W for 10 minutes, and then filtering the solution through a 0.22 μm membrane to remove insoluble matter, thereby obtaining a sodium phytate solution; Step STP500, gradient mixing and maturation, Step STP510, stirring the nano ZnO suspension obtained in step STP100 and the modified water glass obtained in step STP200 at 25° C. and 800 rpm for 15 minutes to obtain a first gradient mixed solution; Step STP520, adding the silane hydrolyzate obtained in step STP300 to the first gradient mixed solution, and maintaining high shear stirring at 40° C. and 1200 rpm for 30 minutes to obtain a second gradient mixed solution; Step STP530, adding the sodium phytate solution obtained in step STP400 dropwise to the second gradient mixed solution, and slowly stirring at 25° C. and 500 rpm for 10 minutes to obtain a third gradient mixed solution; Step STP540, adding deionized water to the third gradient mixed solution to make 100 g, and vacuum degassing under -0.08 MPa for 5 minutes to obtain a fourth gradient mixed solution; Step STP550: transfer the fourth gradient mixed solution to a closed reactor and allow to stand at a constant temperature of 45° C. for 24 hours to obtain a nanocomposite hybrid activator.

4. The method for preparing an activator according to claim 3, wherein: The method further includes the steps of preparing a ZnO@biochar core-shell structure and phytic acid-chitosan self-assembled microspheres, wherein the steps of preparing the ZnO@biochar core-shell structure include: Step STP10, preparation of raw materials: cracking rice husks under oxygen-limited conditions at 500°C to obtain biochar with a specific surface area of ​​800 m² / g; simultaneously, preparing a 0.5 mol / L Zn(NO3)2 solution for later use; Step STP20, impregnation, immersing the biochar in a Zn(NO3)2 solution at a liquid-to-solid ratio of 10:1 and ultrasonically oscillating at a frequency of 40 kHz for 1 h; Step STP30, calcination, heating the mixture to 400°C at a heating rate of 5°C / min under N2 protection and keeping the temperature for 2 hours; Step STP40, reduction, and then placing the calcined product in a mixture of H2 and Ar with a H2 content of 5% at a constant temperature of 300°C for 1 hour to obtain a ZnO@biochar core-shell structure; The steps of preparing the phytic acid-chitosan self-assembled microspheres include: Step STP01, preparation of raw materials, using chitosan with a deacetylation degree of 90%, a 2 wt% acetic acid solution and a 50 wt% aqueous solution of phytic acid for standby use; Step STP02, electrospraying, injecting the chitosan solution at the positive electrode and the phytic acid at the negative electrode into an electrostatic spray device for spraying, wherein the voltage is +15 kV and -10 kV respectively, the receiving distance is 15 cm, and the spray temperature is 25°C; Step STP03, self-assembly, the droplets with opposite charges collide to form phytic acid-chitosan composite microspheres with a particle size of 1-2 μm.

5. The method for preparing an activator according to claim 4, characterized in that: The step of using a microfluidic chip to continuously mix and achieve gradient mixing is also included, which is used to replace step STP500 in claim 3, specifically including: A Y-shaped channel microfluidic chip with a main channel width of 200 μm was used for gradient mixing, wherein Inlet 1 of the microfluidic chip is the modified water glass and ZnO@C suspension obtained in step STP220, and inlet 2 of the microfluidic chip is the silane hydrolyzate and phytic acid microsphere dispersion obtained in step STP330, which are mixed according to the flow rate ratio of 3:1, total flow rate of 10 mL / min, mixing temperature of 30°C, and residence time of 60 s. The ZnO@C suspension in inlet 1 is obtained by adding the ZnO@biochar core-shell structure obtained in step STP40 to deionized water containing 0.5 wt% PAA dispersant at a solid-liquid ratio of 1:9, and then simultaneously performing ultrasonic depolymerization and ball milling-assisted treatment to obtain the ZnO@C suspension. The phytic acid microsphere dispersion at inlet 2 was prepared by adding deionized water to the phytic acid-chitosan composite microspheres obtained in step STP03 and centrifuging at 8000 rpm for 10 min. After repeating this process three times, the precipitated microspheres were mixed with deionized water and ultrasonically dispersed at 40 kHz, 200 W for 10 min to obtain a 5 wt% phytic acid microsphere dispersion.

6. The method for preparing an activator according to claim 5, characterized in that: The control conditions of the ultrasonic deagglomeration are: frequency 40 kHz, power 500 W, and duration 30 min; the control conditions of the ball milling are: grinding with zirconia beads at 300 rpm for 1 h.