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CN-122010482-A - High-corrosion-resistance marine silicate cement and preparation method thereof

CN122010482ACN 122010482 ACN122010482 ACN 122010482ACN-122010482-A

Abstract

The invention discloses high-corrosion-resistance marine silicate cement and a preparation method thereof, and relates to the technical field of marine engineering building materials. The self-repairing cement comprises, by weight, 70-80 parts of silicate cement clinker, 10-15 parts of ultrafine slag powder, 5-10 parts of silica fume, 2-4 parts of double-response self-repairing capsules, 1.5-3 parts of double-function nano composite materials, 0.5-1.5 parts of bio-based loaded inorganic synergistic mineralizer, 3-5 parts of gypsum and 0.02-0.05 part of triethanolamine. The preparation method comprises the steps of drying the raw materials, grinding the raw materials together, and adding the three functional components to uniformly mix. The invention ensures that cement has excellent capabilities of resisting chloride ion corrosion and sulfate corrosion through the synergistic effect of the three functional components, can realize intelligent self-repairing of cracks, and remarkably improves the durability of marine concrete in tidal range, full immersion and sea mud areas.

Inventors

  • MA SHIWEI
  • ZHANG HUAN
  • QI BAODE
  • ZHU ZHAOWEI
  • HAN GUANGFU

Assignees

  • 辽宁交通水泥有限责任公司

Dates

Publication Date
20260512
Application Date
20260105

Claims (10)

  1. 1. The high corrosion resistance marine silicate cement is characterized by comprising the following raw materials in parts by weight: 70-80 parts of silicate cement clinker; 10-15 parts of superfine slag powder; 5-10 parts of silica fume; 2-4 parts of double-response self-repairing capsules; 1.5-3 parts of a dual-function nano composite material; 0.5-1.5 parts of bio-based loaded inorganic synergistic mineralizer; 3-5 parts of gypsum; 0.2-0.5 part of triethanolamine.
  2. 2. The marine silicate cement with high corrosion resistance according to claim 1, wherein the preparation method of the double-response self-repairing capsule is as follows: A1, heating a phase change material to 60 ℃ for melting, adding deionized water and sodium dodecyl sulfate under the condition of 60 ℃ water bath stirring, emulsifying for 10min under 10000-14000r/min high-speed shearing to form an oil-in-water emulsion, adding tetraethoxysilane and ammonia water, stirring at 60 ℃ for reaction for 6h, centrifugally collecting, washing with ethanol for 3 times, and vacuum drying at 60 ℃ to obtain a repairing agent A; the phase change material is refined paraffin or n-octadecane; The phase transition temperature of the refined paraffin is 28 ℃; a2, weighing sodium metasilicate, lithium silicate and lithium sulfate, and uniformly mixing and grinding in a mortar to obtain a repairing agent B; Preparing chloroform solution containing poly (N-isopropyl acrylamide), hexane suspension containing repairing agent A and ethanol solution containing polyvinyl butyral, coating the first layer by using a microfluidic device, wherein the inner phase 1 is hexane suspension containing repairing agent A, the middle phase 1 is chloroform solution containing poly (N-isopropyl acrylamide), the outer phase 1 is polyvinyl alcohol water solution with polyvinyl alcohol concentration of 1%, the flow rate of the inner phase is controlled to be 5 mu L/min, the flow rate of the middle phase is controlled to be 15 mu L/min, the flow rate of the outer phase is controlled to be 40 mu L/min, the single-layer PNIPAM coated microsphere emulsion is collected at 25 ℃, the single-layer PNIPAM coated microsphere emulsion is centrifuged, filtered, washed for 3 times by using absolute ethanol to obtain single-layer PNIPAM coated microsphere, the single-layer PNIPAM coated microsphere is redispersed in absolute ethanol, the prepared to obtain suspension serving as second layer coating, the middle phase 2 is prepared, the slurry formed by mixing repairing agent B powder with ethanol solution containing polyvinyl butyral, the outer phase 2 is controlled to be polyvinyl alcohol concentration of 2% and the inner phase is controlled to be 3 mu L/min, the flow rate of the outer phase is controlled to be 30 mu L/min, and the flow rate of the outer phase is controlled to be 3 mu L/min, the flow rate of the outer phase is collected at 25 mu L/min, and the flow rate of the outer phase is controlled to be 30 mu L; the mass fraction of the poly (N-isopropyl acrylamide) in the chloroform solution containing the poly (N-isopropyl acrylamide) is 5%; the mass fraction of the repairing agent A in the hexane suspension containing the repairing agent A is 10%; The mass fraction of the polyvinyl butyral in the ethanol solution containing the polyvinyl butyral is 8%; In the internal phase suspension used for the second layer coating, the mass ratio of the single-layer PNIPAM coated microsphere to the absolute ethyl alcohol is 1:99; In the intermediate phase slurry used for coating the second layer, the dosage ratio of the powder of the repairing agent B to the ethanol solution containing the polyvinyl butyral is 1g to 5mL; And A4, standing the double-layer coated microsphere emulsion obtained in the step A3 at a low temperature, drying with hot air at 60 ℃ for 12 hours, solidifying the polyvinyl butyral shell, evaporating the solvent, filtering through a 200-400 mesh sieve, collecting particles, and drying with vacuum at 40 ℃ for 24 hours to obtain the double-response self-repairing capsule.
  3. 3. The marine silicate cement with high corrosion resistance according to claim 2, wherein in the step A1, the dosage ratio of the phase change material, deionized water, sodium dodecyl sulfate, ethyl orthosilicate and ammonia water is 10g:200mL:1g:2g:1mL.
  4. 4. The marine silicate cement according to claim 2, wherein in the step A2, the usage amount ratio of the sodium metasilicate, the lithium silicate and the lithium sulfate is 5:2:0.5.
  5. 5. The marine silicate cement with high corrosion resistance according to claim 1, wherein the preparation method of the dual-function nanocomposite is as follows: B1, dissolving cetyl trimethyl ammonium bromide in a mixed solution of deionized water and ethanol, stirring until the mixture is clear, adding ammonia water, stirring in a water bath at 35 ℃ for 30min, dropwise adding tetraethoxysilane, continuously reacting for 6h, centrifuging after the reaction is finished, washing with a mixed solution of ethanol and dilute hydrochloric acid to remove a template agent, drying at 80 ℃, and grinding to obtain mesoporous silica nanospheres; the concentration of the ammonia water is 20-30%; The concentration of the dilute hydrochloric acid in the mixed solution of the ethanol and the dilute hydrochloric acid is 0.1mol/L; B2, preparing an LDH nano sheet by adopting a coprecipitation method, synchronously dripping a mixed salt solution containing magnesium nitrate and aluminum nitrate and a mixed alkali solution containing sodium hydroxide and sodium carbonate into deionized water under the protection of nitrogen and stirring, controlling the dripping speed to be 2mL/min, controlling the pH value of a reaction system to be 10, aging for 18 hours at 60 ℃, centrifuging, washing with water, and freeze-drying to obtain LDH nano sheet powder; the concentration of magnesium nitrate in the mixed salt solution containing magnesium nitrate and aluminum nitrate is 0.2mol/L, and the concentration of aluminum nitrate is 0.1mol/L; the concentration of sodium hydroxide in the mixed alkali solution containing sodium hydroxide and sodium carbonate is 0.8mol/L, and the concentration of sodium carbonate is 0.2mol/L; The volume ratio of the mixed salt solution to the mixed alkali solution to the deionized water is 1:1:2; b3, placing the mesoporous silica nanospheres prepared in the step B1 in a vacuum dryer, vacuumizing at-0.1 MPa and keeping for 1h, dispersing the LDH nanosheet powder prepared in the step B2 in absolute ethyl alcohol to form suspension, injecting the suspension into the dryer, immersing the mesoporous silica nanosphere carrier in the suspension under the condition of keeping vacuum, standing for 24h after normal pressure is recovered, filtering, and drying at 60 ℃ to obtain LDH-loaded silica nanoparticles; The dosage ratio of the mesoporous silica nanospheres to the LDH nanosheets to the absolute ethyl alcohol is 5g to 1g to 50mL; Dissolving sodium silicate and sodium hydroxide in water to form a water phase, dissolving Span-80 emulsifying agent in liquid paraffin to form an oil phase, slowly adding the water phase into the oil phase under high-speed shearing at 8000-12000r/min to emulsify for 15min to form a water-in-oil type microemulsion, and performing spray drying to obtain sustained release agent microspheres; the spray drying operation conditions are that the inlet temperature is 180 ℃ and the outlet temperature is 80 ℃; The dosage ratio of the LDH-loaded silicon dioxide nano particles, the sustained release agent microspheres and the absolute ethyl alcohol is 5g to 1g (20-50) mL; And B5, dissolving a silane coupling agent KH-570 in an ethanol solution with the mass fraction of 95% of ethanol, regulating the pH value to 4-5 by using acetic acid, standing for 30min to obtain a hydrolysate, immersing the composite material obtained in the B4 into the hydrolysate, performing ultrasonic treatment for 10min, reacting for 4h under 60 ℃ stirring, centrifuging, washing, and drying at 80 ℃ to obtain the dual-function nanocomposite.
  6. 6. The marine silicate cement according to claim 5, wherein in the step B1, the dosage ratio of cetyltrimethylammonium bromide, deionized water, ethanol, ammonia water and ethyl orthosilicate is 2 g/480 mL/70 mL/30 mL/10 mL.
  7. 7. The marine silicate cement according to claim 5, wherein in the step B4, the ratio of the sodium silicate, sodium hydroxide, water, span-80 emulsifier and liquid paraffin is 3g:1g:20mL:1g:40mL.
  8. 8. The high corrosion resistance marine silicate cement according to claim 1, wherein the preparation method of the bio-based loaded inorganic synergistic mineralizer is as follows: Preparing a liquid culture medium, sterilizing at 121 ℃ for 20min, inoculating bacillus pasteurizus, shaking and culturing at 30 ℃ and 180r/min for 48h to obtain bacterial liquid, centrifuging and collecting bacterial cells at 8000r/min for 10min at 0-4 ℃, washing with sterile physiological saline, re-suspending in a sterile CaCl 2 solution, standing at 0-4 ℃ for 7 days to induce sporulation, centrifuging and collecting spores again, washing with sterile water, and freeze-drying to obtain spore powder; The liquid culture medium comprises 10g urea, 5g yeast extract, 5g peptone, 10g sodium acetate and 0.1g manganese sulfate per liter, and the pH value is 9; the concentration of the CaCl 2 solution is 0.5mol/L, and the amount is that the bacteria obtained by centrifuging per 100mL of bacteria solution are suspended in 20mL of sterile CaCl 2 solution; Calcining attapulgite at 500 ℃ for 2 hours, cooling and mixing with spore powder prepared by C1 to obtain a mixture 1, dissolving polylactic acid in dichloromethane, dispersing urea and yeast extract powder in the solution, and performing spray drying to obtain polylactic acid microcapsule coated with nutrients; The dosage ratio of the attapulgite to the spore powder to the polylactic acid to the dichloromethane to the urea to the yeast extract is 5g to 1g to 2g to 40mL to 1.5g to 0.5g; The conditions of the spray drying operation are that the inlet temperature is 40 ℃ and the outlet temperature is 25 ℃; Carrying out atomization spraying granulation by using a fluidized bed granulator and taking a mixture 2 prepared by the method C2 as a base material and a hydroxypropyl methyl cellulose water solution with the mass fraction of 5% of hydroxypropyl methyl cellulose as an adhesive, and controlling the temperature of air inlet and materials to obtain bio-based particles; The granulating condition of the fluidized bed is that the air inlet temperature is 50 ℃ and the material temperature is 40 ℃; The mass ratio of the slag silicate cement powder to the water is 1:4.
  9. 9. The marine silicate cement according to claim 8, wherein in the step C2, the mass ratio of the mixture 1, the polylactic acid microcapsule and the carboxymethyl cellulose is (4-6): 0.8:0.2.
  10. 10. A process for preparing a highly corrosion-resistant marine Portland cement according to any one of claims 1 to 9, comprising the steps of: S1, weighing raw materials according to parts by weight, drying silicate cement clinker, gypsum, superfine slag powder and silica fume at 105 ℃ until the moisture is lower than 0.5%, and placing a double-response self-repairing capsule, a double-function nano composite material and a bio-based loaded inorganic matter synergistic mineralizer in a dryer for standby; S2, putting the dried clinker, gypsum, superfine slag powder and silica fume into a planetary ball mill for test, adding triethanolamine, grinding for 45min at a rotating speed of 300r/min, and stopping the machine for cooling for 5min every 15min to obtain a grinding material; s3, transferring the grinding material into a three-dimensional motion mixer, adding the difunctional nanocomposite material at 10r/min, mixing for 15min to enable the difunctional nanocomposite material to be uniformly dispersed, adding the bio-based loaded inorganic substance synergistic mineralizer, mixing for 10min, adding the double-response self-repairing capsule, mixing for 20min at a rotating speed of 5r/min, discharging, vacuum sealing and packaging by using an aluminum foil bag, and storing at a cool and dry place to obtain the composite material.

Description

High-corrosion-resistance marine silicate cement and preparation method thereof Technical Field The invention relates to the technical field of ocean engineering building materials, in particular to high-corrosion-resistance ocean engineering silicate cement and a preparation method thereof. Background Ocean engineering construction is an important component of the national development strategy, however, the durability of reinforced concrete structures by the harsh ocean environment constitutes an unprecedented challenge. The corrosion of the steel bar caused by chloride ion corrosion, the volume expansion damage caused by sulfate corrosion, and the material degradation accelerated by the physical actions of dry and wet circulation, freeze thawing circulation and the like are core factors which lead to the advanced failure of the marine structure and high maintenance cost. Particularly in the areas with frequent dry-wet alternation such as tidal range area and splash area, the erosion process is particularly severe. To improve the durability of marine concrete, the conventional technical route has been mainly developed around the aspects of reducing porosity and thinning pore size by adding a large amount of mineral admixture (such as slag, fly ash and silica fume) and delaying the migration of harmful ions in a physical blocking manner, but the conventional technical route cannot completely prevent the long-term permeation of ions under a concentration gradient and has no self-repairing effect on the formed microcracks. Secondly, external anti-corrosion measures, such as coating or migration type rust inhibitor, are introduced, and the methods have the inherent defects of limited durability, short maintenance period and incapability of repairing internal damage. Thirdly, the development of self-healing technology, the current research has focused mainly on a single mechanism, such as incorporating microcapsules containing healing agents or inducing mineralization by microorganisms. However, the microcapsule technology is usually only responsive to mechanical damage (crack generation) and has no active defense capability to the chemical process of aggressive ion invasion, while the microbial mineralization technology is faced with the problems of strain inactivation caused by the high alkali environment in the early stage of cement hydration, restoration capability termination after the nutrition source is depleted, insufficient bonding strength between mineralized products and a matrix, and the like. More importantly, the prior art mostly adopts a technical stacking strategy, and various means for improving durability lack effective coordination and connection. For example, physical barrier materials cannot intelligently repair damage generated by themselves, chemical adsorption materials lose protection ability after saturation, and local pH values can be changed to bring side effects, and bioremediation processes are often carried out independently of the chemical environment of the materials. The split protection system is difficult to cope with complex erosion process of multi-factor coupling and continuous evolution in marine environment, and cannot realize intelligent and self-adaptive protection of the whole life cycle of the structure. Therefore, development of a novel high-corrosion-resistance marine silicate cement capable of cooperatively solving the problems from the aspects of material composition design and microstructure regulation to function integration has become a technical bottleneck to be broken through in the aspect of long-acting durability in the field of building materials. Disclosure of Invention The invention aims to provide high-corrosion-resistance marine silicate cement and a preparation method thereof, which are used for solving the problems in the background technology. The invention provides high-corrosion-resistance marine silicate cement, which comprises the following raw materials in parts by weight: 70-80 parts of silicate cement clinker; 10-15 parts of superfine slag powder; 5-10 parts of silica fume; 2-4 parts of double-response self-repairing capsules; 1.5-3 parts of a dual-function nano composite material; 0.5-1.5 parts of bio-based loaded inorganic synergistic mineralizer; 3-5 parts of gypsum; 0.2-0.5 part of triethanolamine. As a preferable technical scheme of the invention, the preparation method of the double-response self-repairing capsule comprises the following steps: A1, heating a phase change material to 60 ℃ for melting, adding deionized water and sodium dodecyl sulfate under the condition of 60 ℃ water bath stirring, emulsifying for 10min under 10000-14000r/min high-speed shearing to form an oil-in-water emulsion, adding tetraethoxysilane and ammonia water, stirring for reaction for 6h under 60 ℃, centrifugally collecting, washing for 3 times with ethanol, and vacuum drying under 60 ℃ to obtain a phase change material @ SiO 2 nano material which is named