Contents of this article
The best formula for concrete anti-segregation agent?
What are the ingredients of anti-flocculant?
What kind of ingredients are used to retain water in superplasticizers?
What is cement stabilizer?
What is the chemical composition of the separating agent?
What do anticoagulants include?
What are the ingredients of slime stripper?
What is the best formula for concrete anti-segregation agent?
Concrete, as the largest building material, has developed rapidly. In recent years, high-strength and high-performance concrete has been widely used in engineering. The fluidity of concrete has developed from the previous 70~90mm to the current slump of 180~230mm. Some projects also use self-compacting concrete, and the pumping height is getting higher and higher. However, the fluidity and cohesion of concrete are often incompatible, that is, it is difficult for concrete to maintain high cohesion properties under large flow conditions. In this way, concrete that pursues high fluidity is prone to bleeding and segregation. Moreover, with the gradual depletion of river sand resources and mineral resources in my country, the gradation and fineness of river sand fluctuate greatly, ordinary manufactured sand with poor particle size is used on a large scale, the water retention of cement fluctuates, and high water reduction but The more sensitive polycarboxylic acid-type water-reducing admixtures are constantly being promoted, and the quality control of ready-mixed concrete is facing increasingly severe challenges. The existing concrete anti-segregation agents have a strong flocculation effect, which will cause the concrete to settle quickly and the concrete to lose its flow properties instantly, which is detrimental to the workability of concrete. For this reason, we propose an anti-segregation agent for concrete and its preparation method.
Technical implementation elements:
The purpose of the present invention is to provide an anti-segregation agent for concrete and a preparation method thereof to solve the existing concrete anti-segregation problems proposed in the above background technology. The strong flocculation effect of the agent will cause the concrete to settle quickly, causing the concrete to lose its flow properties instantly, which is detrimental to the workability of the concrete.
In order to achieve the above object, the present invention provides the following technical solution: an anti-segregation agent for concrete, the composition of the anti-segregation agent for concrete is as follows:
Fly ash 5- 15 parts, mineral powder 5-15 parts, steel fiber 1-2 parts, polyethylene glycol 1-2 parts, polyhydroxy acid water reducing agent 20-30 parts, tackifier 0.8-1.2 parts, coagulant 0.5- 0.9 parts, 200-300 parts of deionized water, several parts of liquid alkali, 5-10 parts of silicone monomer, 3-5 parts of oxidizing agent, and 1-3 parts of reducing agent.
Preferably, the organosilicon monomer is propyltrichlorosilane or vinyltrichlorosilane or fluorosilicone monomer or a mixture of the three.
Preferably, the coagulant is powdered sodium sulfate.
Preferably, the tackifier is PAM, and the PAM is moistened with methanol or ethanol, deionized water is added for stirring, and the mixture is heated to 55 degrees Celsius during stirring to prepare a solution with a concentration of 4%.
Preferably, the oxidizing agent is one or a mixture of hydrogen peroxide, ammonium persulfate, and potassium persulfate.
Preferably, the reducing agent is ammonium persulfate-anhydrous sodium bisulfite or ammonium persulfate-sodium hypophosphite.
Preferably, the alkali solution is sodium hydroxide.
Preferably, the preparation method of the concrete anti-segregation agent includes the following steps:
S1: Mixing: combine silicone monomer, deionized water, polyhydroxyacid water-reducing agent and polyethylene glycol are added into the reaction kettle for mixing;
S2: Oxidation: Stir until the mixture in step S1 is evenly mixed, and add oxidant for oxidation;
S3: Reduction: Add fly ash, mineral powder and steel fiber to the oxidized mixture in step S2, and then add the reducing agent;
S4: Neutralization: Add a tackifier to the reduced mixture in step S3 and coagulant, stir continuously until the mixture is uniform, and then add liquid caustic soda to adjust the pH so that the pH is between 7-9, and then the anti-segregation agent for concrete can be obtained.
Compared with the existing technology, the beneficial effects of the present invention are: the invention adds fly ash, mineral powder and steel fiber to the anti-segregation agent, which can not only improve the compressive strength of concrete, but also It can also effectively improve the working performance and stratification of concrete, improve the segregation resistance of concrete, and reduce the expansion and slump of concrete. PAM is used as a tackifier because PAM has more -NH2. The tackifier has good hydrophilicity, making the concrete hydrophilic, water-retaining, thickening, resistance-reducing and viscosity-increasing. Adding calcium sulfate as a setting accelerator can promote concrete water splashing, accelerate hardening, and promote condensation. The invention has wide sources of raw materials, low cost, green and environmental protection, and simple operation.
What are the ingredients of anti-flocculant?
It is aluminum sulfate, aluminum chloride, iron sulfate, and ferric chloride. Aluminum sulfate is an inorganic substance and one of the components of anti-flocculating agent. Its chemical formula is Al2(SO4)3, its molecular weight is 342.15, and it is a white crystalline powder).
In the papermaking industry, it is used as a precipitant for rosin gum, wax emulsion and other rubber materials, as a flocculant in water treatment, and as a retention agent in foam fire extinguishers, as a raw material for manufacturing alum, aluminum white, and petroleum. It can be used as raw materials for decolorizing, deodorizing agents and drugs, etc. It can also produce artificial gemstones, high-grade ammonium alum and anti-flocculating agents.
What kind of materials are used to retain water in water reducing agents?
Concrete admixtures are divided into three generations. The first generation of lignins is basically no longer used. The second generation of naphthalene admixtures has certain environmental pollution. The current market share is not large. The third generation polycarboxylate water-reducing agent is the mainstream in the market. The main raw materials for production are macromonomers (polyether polyols), and the raw materials for macromonomers are��Ethylene oxide, the raw material of ethylene oxide is ethylene, the raw material of ethylene... Wait, basically there is no three waste emissions in the entire production process.
This is why the country actively advocates the application and promotion of third-generation water-reducing agents.
There are also some small ingredients, such as vc, sodium gluconate, sugar, and maltodextrin.
Generally speaking, the current application of water reducing agents is conducive to energy conservation and emission reduction. Even if there are certain environmental hazards. It’s also a pros and cons.
What is cement stabilizer?
Cement stabilizers are also called tackifiers, plastic retaining agents, water retaining agents, etc. Adding thickeners to cement can increase the viscosity of the aqueous solution when the dosage is low.
Since the free water in the cement slurry is restrained, the gaps between the cement particles are preserved, the friction between the particles is reduced, and the mixture is easily deformed. As the viscosity increases, the cohesion increases accordingly, so the segregation resistance of the cement is greatly improved.
What is the chemical composition of the separating agent?
Commonly used separating agents are:
1. Potassium soap separating agent Potassium soap aqueous solution is an anionic surfactant. After being coated on the gypsum surface, it reacts with Ca2+ to form insoluble metal soap substances. Since lipophilic atomic groups (aliphatic hydrocarbons) are arranged on the surface of this layer of material, a hydrophobic molecular film is formed, which can play a role in separating hydrophilic materials. However, this isolation film is soluble in the resin monomer and therefore cannot act as a separating agent between the gypsum and the resin. In oral restoration technology, when making plastic dentures for wax-type boxing, this type of separating agent is commonly used as a separating agent between the upper and lower boxes.
2. Water glass separating agent, namely sodium silicate (Na2SiO3), reacts with Ca2+ on the surface of gypsum to form a calcium silicate film, which plays a role in separating gypsum and gypsum. Generally, a 30% aqueous solution is used. If the concentration is too high, the surface of the gypsum will become rough.
3. Alginate is an aqueous solution containing 2% to 3% sodium alginate. After it is coated on the gypsum surface, it reacts with Ca2+ to form a sodium alginate film that is insoluble in water and resin monomers. This film can be used on the resin. Produce separation from gypsum. Please note when using:
(1) Before coating: Pay attention to completely removing moisture and residual wax from the surface of the model.
(2) When coating: Apply a layer evenly in one direction. It is not advisable to rub back and forth with force, otherwise the formed insoluble calcium alginate film may be wiped off. Wait until it dries to form a thin film before proceeding with other operations.
4. Polyvinyl Alcohol Separating Agent Partially saponified polyvinyl alcohol (PVA) contains a large number of hydroxyl groups in its molecules and is a crystalline polymer with film-forming properties. Although the film formed by polyvinyl alcohol has poor water resistance, it is transparent. It is colorless, has good strength, toughness and high chemical stability, so PVA aqueous solution can be used as a separating agent for pressure-cured resin at room temperature.
5. Glycerin and ethylene glycol separation agent: Both glycerin and ethylene glycol molecules contain hydrophilic groups. After coating on the surface of gypsum, the hydrophilic groups are arranged on the surface of the separation membrane to separate hydrophobic waxes. Glycerin is also used to isolate self-setting resin from the oral mucosa. To separate the inlay wax from the dental tissue or plaster model, liquid paraffin can be used.
6. Vaseline and silicone oil can be used to separate the plastic cast ring from the investment material during ringless embedding, and can also be used to separate the self-setting plastic from the oral mucosa during soft lining.
What do anticoagulants include?
There are five types of anticoagulants: potassium ferrocyanide, sodium ferrocyanide, ferric ammonium citrate, silicon dioxide and calcium silicate. Potassium ferrocyanide is usually used the most.
The main purpose of adding anti-caking agents to edible salt is to prevent the edible salt from clumping. There are a total of 5 food additives allowed in salt in my country that can be used as anti-caking agents, namely potassium ferrocyanide, sodium ferrocyanide, ferric ammonium citrate, silica and calcium silicate. Our country mainly uses potassium ferrocyanide or sodium ferrous hydride. Choose potassium ferrocyanide or sodium ferrocyanide because it is effective and cheap. They are stable and not toxic in daily consumption.
What are the ingredients of slime stripper?
It is composed of bactericides, surfactants, strong
penetrating agents, stabilizers, etc., which can quickly penetrate into the slime bacteria gel mass. Oxidative decomposition releases bubbles, which combine
the action of fungicides and active agents, causing the slime to fall off
and be discharged with the water flow to achieve the purpose of strong peeling and cleaning
Makes the surface clean, thus preventing corrosion under scale.
Chinese name
Components
Sludge stripper
Biocides, surfactants, stabilizers, etc.
Power plants, chemical industry, oil refining, etc. have strong penetrating power, low toxicity and fast action
Product usage characteristics
<img src="/upfile/202304/2023041334528065.jpg"/
微信扫一扫打赏
