597results about How to "Good water reduction effect" patented technology

The invention discloses a normal-temperature synthesis method for a polycarboxylic acid water-reducing agent, and belongs to the field of cement concrete water-reducing agents. The water-reducing agent is prepared by the following steps of: copolymerizing polyoxyethylene ether monomer or polyoxyethylene ester monomer a containing unsaturated double bonds, unsaturated monocarboxylic acid and derivative monomer thereof b, unsaturated dicarboxylic acid c and unsaturated sulfonic acid or salt monomer thereof d in aqueous solution under the action of an oxidation reduction initiator, and finally neutralizing the solution by using alkali solution to obtain the water-reducing agent. The reaction can be performed at room temperature by adopting an oxidation reduction initiating system, and the appropriate reaction temperature is between 5 and 30 DEG C; and the synthesis process does not need heating, so energy is saved, and high-temperature side reaction is effectively controlled. The prepared polycarboxylic acid high-performance water-reducing agent has the characteristics of high water-reducing rate and good collapse protecting performance. The water-reducing agent has wide application range, and the method has low production process requirement and is suitable for industrialized large-scale production.

The invention discloses a phosphoric-acid-base modified polycarboxylic-acid water reducer with high adaptability and a preparation method thereof. The water reducer is prepared from the following raw materials: isopentenol polyoxyethylene ether, hydrogen peroxide, acrylic acid, an unsaturated phosphoric acid monomer, deionized water, a reducing agent, and a chain transferring agent. The chain transferring agent is one of mercaptoethanol, mercaptoacetic acid and mercaptopropionic acid. The unsaturated phosphoric acid monomer is prepared from 2-phosphono-1,2,4-butanetricarboxylic acid, p-toluenesulfonic acid and hydroquinone. The preparation method for the water reducer comprises adding isopentenol polyoxyethylene ether and deionized water into a reaction vessel, uniformly stirring, heating, keeping warm, adding oxygen peroxide, then dropwise adding a material solution by employing a constant-flow pump, continuing to keep warm for reacting for 1-1.5 h after dropwise adding of the material solution is finished, naturally cooling to room temperature, and adjusting the pH value of the obtained product to 5-6 by using an alkaline solution. The phosphoric-acid-base modified polycarboxylic-acid water reducer possesses good sulfate ion resisting capability and sludge resisting capability, thereby satisfying engineering demand.

The refractory material for coke oven door consists of mullite 42-63 wt%, cordierite 20-30 wt%, micro silica powder 5-10 wt%, micro active alumina powder 4-8 wt%, kyanite 3-7 wt%, high alumina cement 3-5 wt%, and composite polyphosphate 0.2-0.5 wt%. The mullite is M60 mullite containing Al2O3 not less than 60 wt%, the cordierite contains Al2O3 33-35 wt% and MgO 13-15 wt%, the micro silica powder contains SiO2 not less than 92 wt%, the micro active alumina powder contains Al2O3 more than 98 wt%, the high alumina cement contains Al2O3 not less than 46 wt%, CaO not more than 40 wt% and SiO2 not more than 10 wt%. The refractory material may be produced into coke oven door through low temperature roasting without need of backing, and the coke oven door has service life over 4 years.

The amphoteric carboxylic acid comb grafted copolymer as concrete super-plasticizing agent is prepared through the following steps: 1) free radical copolymerizing reaction of four kinds of monomers in certain proportion in water soluble medium; 2) crosslinking reaction through introducing crosslinking agent after the polymerization. The present invention proposes that the amphoteric ionic polymer can raise the saturated added amount of concrete super-plasticizing agent, and introduces amphoteric ion concept into the molecular design of concrete admixture. The concrete super-plasticizing agent of the present invention has high water reducing rate, can eliminate the environmental pollution caused by concrete water reducing agent and reduce the added amount while ensuring the outstanding dispersivity and slump maintaining capacity.

It is an object of the present invention to provide a polycarboxylic acid copolymer which improves the water reducing capacity and workability of cement compositions and the like and making them easier to handle when the fluidity and water reducing capacity are at the same levels, a method of producing the copolymer, and a cement additive and a cement composition comprising the copolymer. The present invention is further to provide a polycarboxylic acid copolymer and a cement additive which are capable of improving the strength and durability of hardening products of cement compositions, hence can advantageously be used in ultrahigh strength concrete. The present invention is still further to provide a method of producing polycarboxylic acid copolymers having high water reducing capacity, reducing the viscosity of cement compositions and improving the workability in applying cement.

The present invention is directed to a polycarboxylic acid copolymer which is obtained by copolymerization of monomer components comprising a polyalkyleneimine unsaturated monomer (A1) and an unsaturated carboxylic acid monomer (B).

[Object] To provide a cement dispersant and a concrete composition containing the cement dispersant, the cement dispersant having a superior effect of decreasing a high concrete paste viscosity while a water reducing effect, a slump flow retention, and rapid strength development are being satisfied in a region having a low water/binder ratio.

[Solving Means] The cement dispersant for ultrahigh performance concrete is provided which is a water-soluble amphoteric copolymer obtained by copolymerizing (A) an alkylene oxide adduct of a polyamide polyamine having an unsaturated group, (B) (meta)acrylic acid or a salt thereof, (C) an ester of a short-chain alkylene glycol and (meth)acrylic acid, and (D) an ester of a long-chain alkylene glycol and (meth)acrylic acid at ratios A:B:C:D of 5 to 25:5 to 30:5 to 40:20 to 80 (percent by weight), in which the total is 100% percent by weight. In addition, the concrete composition containing the above cement dispersant is provided.

The invention provides a ferronickel slag ultrahigh-strength concrete and a preparation method thereof. Every cubic meter of ferronickel slag ultrahigh-strength concrete contains 550-700kg of cementing material, 900-1000kg of coarse aggregate, 800-900kg of fine aggregate, 8-20kg of polycarboxylic-acid high efficiency water reducing agent and 160-170kg of water. The cementing material is composed of the following components in percentage by mass: 50-60% of P.O 52.5 Portland cement, 15-20% of ore powder, 5% of silica fume and 20-30% of ferronickel slag micropowder. The ferronickel slag is used as crude aggregate, fine aggregate and a mineral admixture respectively instead of natural gravel, sand and part of cement. Besides, the ferronickel slag has favorable water-reducing actions, can greatly improve the placeability of concrete, and obviously increases the slump constant. The 25-day compression strength of the ferronickel slag ultrahigh-strength concrete can reach 110 MPa or above, which is much higher than the non-ferronickel-slag concrete.

The invention discloses a compound concrete admixture with early strength and water reduction functions. The compound concrete admixture is mainly prepared by 10-20 parts by mass of a polycarboxylate water-reducer, 1-5 parts by mass of a surfactant, 5-40 parts by mass of an early strength agent, 2 or less parts by mass of an air entraining agent, and 20-100 parts by mass of water. The preparation method of the compound concrete admixture comprises the following steps: processing a polycarboxylate water-reducer mother liquor to prepare a solution, mixing the polycarboxylate water-reducer solution with the early strength agent, the surfactant, the air entraining agent and water according in proportion, and uniformly stirring. The application of the concrete admixture is realized through the following steps: stirring the concrete admixture and standard sand; taking cement and water, and carrying out low-speed uniform mixing; mixing the above two materials, carrying out low-speed stirring, then carrying out high-speed stirring, intermediately stopping, and then continuously carrying out high-speed stirring; and adding the finally obtained mixture into a mold, and maintaining, wherein the addition of the polycarboxylate water-reducer is not greater than 1% of the amount of a cement mortar. The compound concrete admixture has the advantages of simple preparation method, fast effectiveness, wide application range, low cost and good effect.

The amphoteric carboxylic acid comb grafted copolymer as concrete super-plasticizing agent is prepared through the following steps: 1) copolymerizing three kinds of monomers in certain proportion in water soluble medium to obtain intermediate product PCE; 2) preparing cationic copolymer CNP through Hofmann degradation or Mannich reaction of polyacrylamide or the copolymerization of acrylamide monomer and two other kinds of monomer in water soluble medium; 3) mixing the copolymer PCE and polymer CNP through stirring to obtain amphoteric carboxylic acid grafted copolymer; and 4 ) heating the comb grafted copolymer produced in the last step to 60-100 deg.c and adding crosslinking agent to produce crosslinking reaction producing the amphoteric carboxylic acid comb grafted copolymer. The concrete super-plasticizing agent of the present invention can reduce the water consumption of concrete greatly, and has excellent construction performance.

This invention discloses a high-performance lignin-based water reducer with high degree of sulfonation and high molecular weight and its preparation method. This water reducer exhibits an excellent water-reducing performance, its water-reducing rate of this lignin-based water reducer reaches 25% at a dosage of 0.70 wt %, which is higher than that of the naphthalene-based water reducer and the sulfonated lignin water reducer prepared by oxidation and sulfonation of alkali lignin, and 28-days compressive strength ratio of the concrete with this water reducer to the concrete without this water reducer is up to 150:100. Furthermore, the water reducer of present invention will not be crystallized in winter, and the concrete iron won't be corroded. The water reducer of the present invention makes the concretes having a low bleeding rate, excellent properties of workability, anti-freeze and anti-carbonization.

The invention discloses a preparation method and application of a powdery polycarboxylic acid water-reducing agent. The preparation method comprises the following steps: preparing from a carboxylic acid monomer a, a benzene ring-containing small monomer b and a benzene ring-containing polyether monomer c in an aqueous medium through free radical copolymerization to obtain polycarboxylic acid water-reducing agent mother liquor; and directly forming the polycarboxylic acid water-reducing agent mother liquor into fog drops through a centrifugal atomizer for a sprayer without adding an isolation agent, controlling the average particle size of powder to be 50-150 [mu]m, drying into powder after the fog drops enter a drying room, leading a material to a discharge port through an induced draft fan, and packaging and discharging by adopting a bagged packaging machine to obtain the powdery polycarboxylic acid water-reducing agent. The preparation method disclosed by the invention has the benefits that not only is the effective content of polymers in the powder improved, but also the production technical process is reduced, and the production cost is reduced; and the prepared powdery polycarboxylic acid water-reducing agent is optimal in fluidity, incapable of caking, high in storage stability, low in long-distance transportation cost, excellent in water-reducing property and suitable for various dry mortar.

The invention belongs to the technical field of building materials, and particularly relates to cement-based self-leveling dry powder mortar for the ground. The cement-based self-leveling dry powder mortar for the high-cracking-resistance ground consists of cement, fine sand, heavy calcium powder, lithium slag powder, an expanding agent, a solidification adjusting agent, a super plasticizer, a defoaming agent and cracking-resistant fiber. The cement-based self-leveling dry powder mortar for the high-cracking-resistance ground has the characteristics of low cost, high flowing property, bleeding resistance and adjustable setting time during construction as well as high intensity, high cracking resistance, high wearing resistance and flat surface after being hardened. The dry powder mortar has high performance and low cost, and can be widely applied to the fields of ground engineering such as factories, warehouses, shopping plazas, parking lot terrace and the like.

A cement admixture object of the present invention can make slump-retaining ability excellent to retain fluidity and, at the same time, can realize a viscosity of cement compositions so that work becomes easy at a field handling them, can make the state of a cement composition better. The present invention relates to a cement admixture which comprises a polycarboxylic acid copolymer having a polyalkylene glycol side chain, said polycarboxylic acid copolymer being constituted of two or more species of copolymers with different acid values, and at least one of said two or more species of copolymers with different acid values having an oxyalkylene group containing 3 or more carbon atoms.

The invention discloses a method for preparing vinyl aromatic line polyether graft concrete superplasticizer which is prepared by using the following steps: (1) esterification: catalytic esterification is carried out to chemtura alkyl diol monoalkyl ether and maleic anhydride for obtaining an esterification product; (2) copolymerization: under the action of initiator, the esterification product, vinyl aromatic monomer and vinyl acetate are copolymerized for obtaining a polymerization product; (3) sulfonation reaction: under the action of sulfonation reagent, two sections of sulfonation reaction (low-temperature and high-temperature sulfonation) are carried out to the polymerization product for obtaining a sulfonation product; and (4) neutral reaction: the pH value of the sulfonation product is adjusted to be 7-8, and then diluted by water for obtaining the concrete superplasticizer with certain concentration. The invention can adjust product performance by controlling the product structure, does not use solvent in the process of reaction, is non-toxic and non-polluting, is safe to the environment, and has stable product performance, better security and water reducing property.

The invention discloses cement base permeating crystallizing waterproof paint formed by reinforcing straw fibers, and belongs to the technical field of building materials. The cement base permeating crystallizing waterproof paint is compounded from the following raw materials in percentage by weight: 30-60% of silicate cement, 10-25% of modified magnesite cement, 10-25% of fillings, 5-12% of quartz sand, 0.1-0.5% of expanded vermiculite powder, 0.05-0.2% of straw fibers, 0.8-1.5% of a chelating agent, 0.5-2% of a crystallizing precipitant, 1-5% of an ionic equilibrium agent, 0.1-0.3% of an antifoaming agent, 0.1-1% of redispersible latex powder and 0.3-0.6% of a water reducing agent. The cement base permeating crystallizing waterproof paint formed by reinforcing the straw fibers, disclosed by the invention, has double waterproof properties, good permeation resistance, good self-healing and repair capacity, good water pressure resistant capacity and rapid crack repairing capacity, is simple in production technology, low in cost and environment-friendly, and has the same life as that of concrete.

The invention provides a preparation method and application of a phosphate-group-containing low-molecular-weight water reducing agent for concrete. The preparation method can improve the density of phosphate adsorption groups in the water reducing agent, and the prepared water reducing agent has excellent slump loss resistance, water reducing performance, retarding performance and clay tolerance.The preparation method comprises the following steps: (1) reacting a part of hydroxyl groups in polyether polyol of a specific structure with an alkali metal or alkali metal compound to produce an alkali metal salt of polyether polyol; (2) subjecting the alkali metal salt of polyether polyol and chlorinated polyether of a specific structure to an etherification reaction so as to synthesize a polyether intermediate containing hydroxyl groups; and (3) phosphorylating the hydroxyl groups of the polyether intermediate.

The invention relates to an enhanced polycarboxylic acid system concrete reducing agent and a preparation method therefor. The enhanced polycarboxylic acid system concrete reducing agent comprises the following raw materials and components in percentage by weight: 15%-27% of a high water reduction polycarboxylic acid water reducing agent, 5%-10% of organic amine compounds, 2.5-5% of cellulose ether, 0.5%-1% of polyvinyl alcohol , 0.1%-0.5% of sodium nitrite and 64.9%-73.7% of water. The enhanced polycarboxylic acid system concrete reducing agent prepared by the method disclosed by the invention has a high water reduction effect, contains a great number of strong polar hydrophilic radicals with high dispersed and chelated capacity, can stimulate the action of concrete to the maximum extent, effectively disperses gelled materials, obviously improves the working performance of the concrete, and has a remarkable enhancing effect on the later strength of the concrete; 10.7%-15.5% of cement in the concrete is reduced, the adaptability is good, and the technical economy benefits of commercial concrete are ensured.

The invention discloses a waterproof type phase-change heat storing plaster wallboard formed by reinforcing straw fibers. The plaster wallboard is compounded from the following raw materials in percentage by weight: 20-60% of plaster gelate materials, 10-25% of phase-change heat storing microcapsules, 1-7% of a composite water repellent, 25-55% of mineral micro powder, 0.1-0.6% of straw fibers, 0.8-1.5% of a binder, 1-5% of an exciting agent and 0.2-1.5% of a water reducing agent. The preparation method comprises the following steps of: 1) firstly, adding the plaster gelate materials, the mineral micro powder, the straw fibers and the exciting agent into a reaction kettle, adding water, and uniformly stirring the plaster gelate materials, the mineral micro powder, the straw fibers, the exciting agent and the water so as to obtain a material A; 2) sequentially adding the phase-change heat storing microcapsules, the composite water repellent, the binder and the water reducing agent into the reaction kettle, and stirring the material A, the phase-change heat storing microcapsules, the composite water repellent, the binder and the water reducing agent once again so as to obtain a material B; and 3) directly pouring the material B in the reaction kettle into a mold through a grouting pump so as to obtain the phase-change heat storing plaster wallboard, wherein a fiber cement board is arranged on the inner surface of the mold. The waterproof type phase-change heat storing plaster wallboard disclosed by the invention has the advantages of being suitable for operation under humid environment, simple in production technology and environment-friendly.

The present invention provides the recipe of chlorine ion penetration resisting reinforcer for concrete in harbor engineering. The chlorine ion penetration resisting reinforcer consists of superfine silica powder 15-20 wt%, washed and calcined kaolin 20-25 wt%, high grade fly ash 20-25 wt%, ground blast furnace slag 20-25 wt%, nanometer fiber 5-10 wt%, superplasticizer 6 wt%, slump keeping agent 0.09 wt%, air entraining agent 0.09 wt%, and organic active excitant 0.12 wt%. The chlorine ion penetration resisting reinforcer has inorganic components as main functional materials dispersed homogeneously in concrete cementing material, and can improve the micro structure and hydration product composition inside concrete, raise compactness, adsorb and fix chlorine ion and lower the penetration of chlorine ion in hardened concrete, so as to improve the chlorine ion penetration resisting capacity of hardened concrete.

The invention relates to a high-efficiency polycarboxylic acid water-reducing composite agent prepared by complexation of a polycarboxylic acid water-reducing agent, cellulose ether, sodium lauryl sulfate, propylene-benzene core-shell emulsion, nano-silica, lignin sulfonate, a defoaming agent, sodium nitrite, an amine alcohol enhancer, and water. The formula is reasonable, and has reliable performance. The polycarboxylic acid water-reducing agent has good water-reducing effect, wherein a water-reducing rage can be higher than 35%. When the water-reducing agent is reasonably complexed with a set retardant, a defoaming agent, an enhancing agent, an early-strength agent, and a preservative, product adaptability can be improved, and consumer application requirement can be satisfied. According to a polycarboxylic acid water-reducing agent production device, intermediate heating can be carried out upon reaction materials in a kettle with a heating medium in a jacket layer; information of a flow meter and a thermometer can be collected by a controller; a motor and the flow meter can be further reasonably controlled, such that the materials in the kettle re polymerized strictly according to a preset condition; with a complex tank, accurately measured materials can be uniformly mixed, such that reliable water-reducing agent product quality can be ensured. The product has good popularization value and market prospect.

The invention provides polyaspartic acid containing unsaturated double bond, a retarding and plastic-retaining type polycarboxylate superplasticizer and a preparation method thereof. The polyaspartic acid and unsaturated carboxylic acid containing non-conjugated C=C double bond perform an amidation reaction to polyaspartic acid containing unsaturated double bond shown in the structural formula (I); the polyaspartic acid and a selected unsaturated monomer perform addition and copolymerization reaction to obtain a retarding plastic-retaining type polycarboxylate superplasticizer shown in the structural formula (II). Experiment results prove that the retarding and plastic-retaining type polycarboxylate superplasticizer can be more effectively used for retarding formation of an ettringite structure in the cement hydration process to achieve a longer retarding time and better plastic retaining performance, so that the performance maintaining time of blended concrete can be prolonged.

The invention discloses a road paving material taking building waste as a main material and a preparation method of the road paving material. Based on total weight of the road paving material, the road paving material comprises the following materials in percent by weight: 5-15% of active micro powder prepared from red bricks, black bricks, tiles and/or crushed glass, 80-90% of mud material separated from building waste and 0.02-0.08% of activator, wherein over 99% of the road paving material is prepared from the building waste. The road paving material disclosed by the invention enables the building waste to be sufficiently utilized while satisfying road index requirements.