35results about How to "Strong slump retention" patented technology

The invention discloses a slow release type efficient polycarboxylic acid water reducer and a preparation method thereof. The slow release type efficient polycarboxylic acid water reducer is composed of the following materials: acrylic acid, maleic anhydride, polyoxyethylene ether macromonomer, a macromolecule template agent, sodium hydroxide, deionized water, a peroxide initiator and a chain transfer agent. The preparation method comprises the following steps: adding sodium hydroxide and deionized water into a stirring kettle to prepare a sodium hydroxide solution; dropping acrylic acid into the sodium hydroxide solution by using a peristaltic pump to obtain a reaction liquid A; adding the peroxide initiator and deionized water into a material barrel to obtain a dissolving solution B; adding the chain transfer agent and deionized water into a material barrel to obtain a dissolving solution C; adding the polyoxyethylene ether macromonomer, maleic anhydride and the macromolecule template agent into a reaction kettle, and sucking out deionized water to obtain a reaction liquid D; adding the reaction liquid A, the dissolving liquid B and the dissolving liquid C into the reaction liquid D by using a peristaltic pump to obtain the slow release type efficient polycarboxylic acid water reducer. The water reducer provided by the invention has slow release property, relatively high water reducing efficiency, and good water reducing performance and slump loss resistant property.

The invention provides a foam control agent and an air-entraining water reducing compounding agent and concrete prepared thereof. The foam control agent is mainly formed by compounding the following components by weight: 5-40% of an alkynol wetting agent E20, 40-70% of an alkynol wetting agent E40, 20-50% of an alkynol wetting agent E65, and the balance other accessories. The foam control agent has double technical effects of air entraining and foam control, can control the foam density and the foam size of a system, makes foams more uniform, eliminates big harmful foams, and makes the cement strength, stability and other properties improved.

The invention provides a preparation method and an application of a concrete plasticizer with improved clay adaptability. The concrete plasticizer serves as a dispersing agent of water dispersion of ahydraulic binding agent and / or a potential hydraulic binding agent, and has good clay adaptability, better water reducing capability and higher slump loss resistance. The preparation method comprisesthe step of allowing an ingredient a, a monomer b, a monomer c and aldehyde d to give a copolycondensation under the condition of a combined catalyst e to form the concrete plasticizer. The weight-average molecular weight of the concrete plasticizer is 10000-40000; the ingredient a comprises an aryl polyether monomer a-1 with a terminal subjected to phosphonate esterification, and an optional aryl polyether monomer a-2 with hydroxyl as a terminal; the monomer b is an aryl monomer with a carboxylic ester group; the monomer c is an aryl monomer with COOH, SO3H or OPO3H2; and the combined catalyst e is a composition of protonic acid e-1 and non-protonic acid e-2.

The invention provides a preparation method of polycarboxylic acid nanoparticles. The polycarboxylic acid nanoparticles are formed through copolymerizing a hydrophilic monomer unsaturated acid, a hydrophilic monomer polyethylene glycol monomethyl ether methacrylate, a hydrophilic monomer unsaturated sulfonate and a hydrophobic monomer styrene or (meth)acrylate, and have a linear microstructure in water. The water reducer applied to concrete has the advantages of low proportion, high water reduction, long slump retaining time and excellent mud resistance; and the polycarboxylic acids particles solves the water reducing and slump retaining problems of concrete without a super water reducer or an extra sacrificing agent when the mud content of aggregates is high, so the water reducer has good economic benefit.

The invention discloses a slump-prevention-type concrete pumping aid, which comprises naphthalene or homolog thereof, aliphatic compounds, sodium gluconate, carboxylic acid grafted copolymers, lauryl sodium sulfate, formaldehyde cellulose, hydroxymethyl propyl cellulose, wherein the percentage by weight of the naphthalene or homolog thereof is 60%-80%; the percentage by weight of the aliphatic compounds is 6%-8%; the percentage by weight of sodium gluconate is 1%-5%; the percentage by weight of carboxylic acid grafted copolymers is 1%-5%; the percentage by weight of the lauryl sodium sulfate is 1%-3%, the percentage by weight of formaldehyde cellulose is 0.1%-0.5%, and the percentage by weight of the hydroxymethyl propyl cellulose is 0.1%-0.5% and the balance of water. According to the slump-prevention-type concrete pumping aid provided by the invention, on the basis of summarizing the common method of slump loss control, the carboxylic acid grafted copolymers are compounded into a naphthalene water reducer, and the slump-prevention-type concrete pumping aid has the characteristics of good dispersion property and high slump retaining capability, and solves the problem of rapid naphthalene doped pumping aid concrete slump loss.

The invention discloses a preparation method of a high water-reducing rate branched chain type aliphatic series water reducing agent. The preparation method comprises the following steps of: in parts by mass, adding 40-60 parts of sulfite and 220 parts of water into a reaction kettle; stirring for dissolving; adding liquid alkali to adjust the pH value of the solution to be 13; dropping 50-60 parts of acetone within 0.5-1 hour; controlling the reaction temperature to be 45-55 DEG C; preserving the temperature for 0.5 hour; dropping 170-190 parts of methanal within 1.5-2.5 hours; controlling the temperature to be less than or equal to 85 DEG C; adding a mixture solution prepared from 10-25 parts of polyoxyethylene ether macromonomer and 100 parts of water; dropping another mixture solution prepared from 2-5 parts of a water-soluble oxidation-reduction initiator and 40 parts of water into the system; preserving the temperature for 2-3 hours; and cooling to the room temperature so as to obtain the water reducing agent. The water reducing agent prepared by using the preparation method is greatly improved in water reducing rate, is enhanced in collapse-prevention function, and is high in air content good in air conduction capability; and the problem that bleeding is easy is overcome.

The invention discloses a polyphosphoric acid water reducer and a preparation method thereof. The polyphosphoric acid water reducer of the present invention is made of phosphoric acid polyether, polyethylene glycol monomethyl ether and phosphoric acid compound A in a molar ratio of 1:1.05 ~ 1.2 through esterification of phosphoric acid polyether, polyethylene glycol, Alkyl glycol, phosphoric acid compound B and water-carrying agent are produced by esterification and dehydration reaction; the molar ratio of phosphoric acid polyether, polyethylene glycol, alkyl glycol and phosphoric acid compound B is 1:1.5~3:0.2 ~2:1~4. The water-reducing agent of the present invention has simple production process, cheap and easy-to-obtain raw materials, low equipment investment, and easy industrial scale-up production; the reaction process has little pollution, the water-carrying agent can be recycled, and saves a lot of transportation costs; it has stronger water-reducing and The slump retention ability can improve the workability of concrete, has good adaptability to concrete materials in different regions, and has strong tolerance to sand and gravel aggregates with high clay and high sulfate content, and has broad market application prospects.

The invention provides water-plastic retaining polycarboxylic acid water reducer and a method for preparing same, belonging to the technical field of the cement dispersant. The water-plastic retaining polycarboxylic acid water reducer is characterized by being prepared in nature through copolymerizing a big water-plastic retaining monomer and a small water-plastic retaining monomer, wherein the big water-plastic retaining monomer is prepared by mixing a big ester monomer with a small ester monomer. Prepared from the big water-plastic retaining monomer, the water-plastic retaining polycarboxylic acid water reducer can well retain the water and the plastic of concrete which is prepared through stirring different cement and different aggregate, and the ubiquitous problems of the segregation due to water bleeding and the quick slump loss are effectively solved. The water is used as solvent for the polymerization reaction, which is good for the industrial production and ensures the safe and environmental-friendly production process.

The invention discloses a method for preparing a phosphate functional monomer by a P2O5 dispersion method and application. The invention relates to a method for synthesizing a phosphate functional monomer by feeding a polymerizable unsaturated organic compound dispersed P2O5, wherein a polymerizable unsaturated organic compound dispersing agent used in a synthesis process can participate in a subsequent polymerization reaction, thereby solving the problems of difficult separation and recovery of a low-boiling-point and toxic organic solvent adopted in a preparation process of an existing phosphate functional monomer and environmental pollution, and simultaneously simplifying the synthesis route of the phosphate functional monomer. The invention also discloses a method for preparing a high-performance polycarboxylate superplasticizer by taking a phosphate functional monomer solution with a polymerizable unsaturated organic compound as a solvent as a third monomer of a polycarboxylate superplasticizer, so that the problem of contradiction between dispersion capacity and slump retention capacity of an existing polycarboxylate superplasticizer is solved, and a method for preparing a high-performance polycarboxylate superplasticizer with high dispersion and slump retention capacity and strong cement adaptability is provided.

The present invention provides an amphiphilic polycarboxylic acid cement dispersant and a preparation method thereof. The amphiphilic polycarboxylic acid cement dispersant is a polycarboxylic acid particle dispersion liquid with wormlike micromorphology; the amphiphilic polycarboxylic acid cement dispersant comprises amphiphilic polycarboxylic acid nanoparticles and water; the weight-average molecular weight of the amphiphilic polycarboxylic acid nano particles is 15000-40000; the amphiphilic polycarboxylic acid cement dispersant has the advantages of excellent water reducing property, slump loss resistance, adjustable structure and the like of a polycarboxylic acid, and also has the functions of improvement of concrete mechanical properties such as flexural strength, compressive strength and impermeability of a nano material.

The invention relates to a method for low temperature esterification synthesis of a comb-type carboxylic acid polymer. The method comprises the steps: under a vacuum condition, stirring evenly a monohydroxyl polyether and polyacrylic acid aqueous solution and a catalyst having the mass being 0.2-4 wt% of the monohydroxyl polyether and polyacrylic acid in reactant, and introducing nitrogen gas; and under a vacuum condition, adjusting the flow quantity of nitrogen gas to control the gas pressure, heating up to an esterification reaction temperature, then adding a solid acid catalyst with the mass being 0.1-2 wt% of the total mass of the monohydroxyl polyether and polyacrylic acid in reactant, carrying out esterification for 4-8 h, and synthesizing the comb-type carboxylic acid polymer. With use of the method for direct esterification of polyacrylic acid and polyethylene glycol monoether macromolecules to synthesize the polycarboxylic acid water reducing agent under catalysis of a high-catalytic-activity catalyst, the method has the characteristics of simple process, large molecular structure design freedom degree of the product, stable product quality, low reaction temperature, low energy consumption and low production cost.

The invention discloses sustained-release polycarboxylate superplasticizer and a preparation method and application thereof.The sustained-release polycarboxylate superplasticizer is prepared from, by weight, 50-58 parts of polymethylacrylic acid, 22-30 parts of castor beans, 5-12 parts of menthone, 8-15 parts of chitosan, 1-5 parts of potassium ferrate and 33-40 parts of formic acid.The castor beans are dried, smashed and sieved, cyclohexane is added into the sieved castor bean powder, sealing heating is conducted, and supernatant liquid is extracted after filtering; the supernatant liquid and chitosan are mixed, sealing heating is conducted, and a mixture A is obtained; polymethylacrylic acid and formic acid are mixed, deionized water is added, heating and stirring are conducted, menthone is added, heating and stirring are conducted, and a mixture B is obtained; the mixture A and the mixture B are mixed, and after heating and stirring are conducted, potassium ferrate is added, heating is conducted, and the sustained-release polycarboxylate superplasticizer is prepared.The sustained-release polycarboxylate superplasticizer has sustained-release performance, the water reducing efficiency is higher, good water reducing performance and slump retaining performance are shown, the sustained-release polycarboxylate superplasticizer also has the defoaming function, sources of the raw materials are wide, the production technology is simple, cost is low, no environment pollution is caused, and the sustained-release polycarboxylate superplasticizer is suitable for industrial production.