603results about How to "Good slump performance" patented technology

The invention discloses a high-performance polycarboxylate water reducing agent. The polycarboxylate water reducing agent has a structural general formula shown as a structural formula (I). The invention further provides a preparation method of the high-performance polycarboxylate water reducing agent. Apart from a polyether macromonomer and an unsaturated carboxylic acid monomer, an unsaturated phosphate monomer is added to obtain a product, namely, the high-performance polycarboxylate water reducing agent having a phosphate structure. The polycarboxylate water reducing agent disclosed by the invention is safe and simple in preparation process, environmentally friendly, low in energy consumption, low in cost, and suitable for industrial large-scale production. In the structural formula (I), R1 is -H, -COO- or -CH2COO-; R2 is -H or -CH3; R3 is -H or -CH3; R4 is -H or -CH3; R5 is -H or -CH3; R6 is -CH2- or -CH2CH2-; X, Y, Z and n are integers; X=1-100; Y=1-100; Z=1-100; and n=22-53.

The invention relates to a preparation method of a star polycarboxylic acid high-performance water reducing agent. Polybasic alcohol and (methyl) acrylic acid used as main raw materials for esterification are esterified and polymerized to prepare the star polycarboxylic acid high-performance water reducing agent material: the (methyl) acrylic acid and polybasic alcohol used as reactants are esterified under the action of a catalyst to firstly prepare a star polymerizable active terminal, and free-radical polymerization reaction is carried out with unsaturated polyethenoxy ether, molecular weight regulator and unsaturated carboxylic acid monomer under the action of an initiator to prepare the star polycarboxylic acid high-performance water reducing agent. The invention is easy to control, and has the advantages of high polymerization degree, low cost and no pollution; the esterification reaction is carried out form an active core, and the free-radical polymerization is carried out to generate the chain arm, thereby implementing the polycarboxylic acid high-performance water reducing agent in a star molecular structure; and under the condition of common doping amount and low doping amount, the star polycarboxylic acid high-performance water reducing agent has better cement paste flowability and holding capacity than the traditional linear and comb polycarboxylic acid water reducing agents, and has favorable cement adaptability and concrete application performance.

The invention relates to a slow release slump retaining polycarboxylate water reducer and a preparation method thereof. The method comprises the specific steps of: carrying out ration on unsaturated polyoxyethylene ether, acrylic acid, acrylic acid ester monomers, crosslinking monomer, initiator, chain transferring agent and water for 4-7 h at a reaction temperature of 80-90 DEG C; cooling to 35-40 DEG C; adjusting a pH value of the solution to neutral to obtain a colorless and transparent solution, namely the slow release slump retaining polycarboxylate water reducer. The water reducer prepared by the invention employs two modes of hydrolysis and maintains functions in a cement system for a long time through hydrolysis of ester group on polyacrylic acid monomers and ester group on crosslinking monomer, so as to realize control of slump loss. The slow release slump retaining polycarboxylate water reducer can obviously increase net paste fluidity after one hour, has good retentivity on net paste fluidity after two hours and can maintain nearly zero loss on slump after one hour.

The invention discloses an ester slump retaining type polycarboxylate water reducer and a preparation method thereof. The ester slump retaining type polycarboxylate water reducer is made from raw materials comprising the following components in parts by weight: 100 parts of esterified macromer solution by weight, 2-6 parts of unsaturated monomer by weight, 1.5-4 parts of unsaturated phosphate by weight, 1-4 parts of an oxidizing agent by weight, 0.9-3.5 parts of a reducing agent by weight, 1-3 parts of a chain transfer agent by weight, 108 parts of water by weight, and 20 parts of industrial sodium hydroxide solution by weight, wherein the concentration of the esterified macromer solution is 75-85%, and a solute thereof is the mixture of methoxy polyethylene glycol methacrylate, crosslinking monomers triethylene glycol dmethylacrglate and methyl methacrylate; the unsaturated monomer is methacrylic acid, acrylic acid, hydroxyethyl methylacrylate, hydroxyethyl acrylate, hydroxypropyl methacrylate or hydroxypropyl acrylate. The ester slump retaining type polycarboxylate water reducer provided by the invention has good slump retaining performance, good dispersibility, good adaptability and low cost.

The invention proposes a compounding formula and manufacture method of a sustained release-type polyocarboxy acid high performance water reducing agent. The compounding formula comprises esterification reaction formula and copolymerization reaction formula. The invention combines the esterification reaction and copolymerization reaction into one to carry on after the improvement of the craftwork. The invention utilizing non-solvent esterification method achieves the esterification reaction in the lower temperature (75 DEG C) through using the compound catalyst. Compared with the two steps, the invention has better application performance. The invention synthesizes sustained release-type polyocarboxy acid high performance water reducing agent through the adjustment of the reaction condition and the kind and type of components in each reaction. The product is suitable for the concrete with high request to the control of the slump.

The invention relates to the technical field of concrete admixtures, in particular to a clay-resisting slow-release slump-retaining type polycarboxylate superplasticizer and a preparation method thereof. With polyether macromonomers, unsaturated carboxylic acid, unsaturated carboxylic ester, dibasic acid anhydride, a crosslinking agent, amide monomers, unsaturated phosphate ester, phosphate, an oxidizing agent , a reducing agent, a chain transfer agent, a neutralizing agent and water as raw materials, the clay-resisting slow-release slump-retaining type polycarboxylate superplasticizer is synthesized at normal temperature. Ester groups, amide groups and phosphate ester are introduced into the molecular structure of the polycarboxylate superplasticizer, and light crosslinking of the polycarboxylate superplasticizer is realized through the long-chain ester crosslinking agent, so that the superplasticizer has a good clay-resisting and slump-retaining effect and has the advantages of low mixing amount, high water reducing rate, high adaptability to clay-containing sand, good slump retaining performance and the like; besides, only normal-temperature polymerization is needed, the processis simple, the production cost is low, and the superplasticizer is suitable for industrial production.

The invention relates to a green preparation method of a slow-release polycarboxylic-acid high-performance water reducing agent, which comprises the following steps: firstly, dissolving unsaturated polyethenoxy ether in water, adding an oxidant solution, and evenly stirring; then, respectively and dropwisely adding a reducer/chain-transfer agent mixed solution and a comonomer solution, and polymerizing; and finally, adding an alkaline regulator to neutralize and age the solution, thereby obtaining the slow-release polycarboxylic-acid high-performance water reducing agent. In the invention, hydrogen on the terminal hydroxyl group of the original unsaturated polyethenoxy ether is substituted by an allyl group containing unsaturated bond, so that the terminal group of methoxypolyethylene glycol is converted from the original active hydroxyl group into the inert methoxy group at present; and thus, the byproducts of the copolymerization product are greatly reduced, and the molecular weight distribution is narrow, so that the synthesized water reducing agent has the advantages of high water reduction rate and slump resistance. The redox system with low activation energy is used for initiating the monomer copolymerization, so that the polymerization can be implemented at normal temperature, thereby implementing the production of the product by a no heat source method, simplifying the production equipment and lowering the energy consumption and cost.

The invention relates to highly-antifreezing highly-slump retaining self-compacting C40 concrete which comprises the following components by kg/m3: 330 parts of cement, 80 parts of granulated blast-furnace slag, 80 parts of fly ash, 830 parts of natural medium sand with a fineness modulus of 2.3-3.0, 920 parts of stone, 4.9 parts of additives, and 160 parts of mixing water; the additive is a modified air-entraining polycarboxylic water reducer, wherein the mixing amount of an air-entraining agent in the polycarboxylic water reducer RP325 is 0.1%, and the mixing amount of the additive for large-scale production is 1.0% of the total amount of gel materials; the air content in the concrete is 5.0%+/-1.0%; the air-entraining amount in the poured structure from the beginning to the third hour is stabilized within a range of 5.0%+/-1.0%, and the concrete expansion degree in 3 hours is maintained at 600+/-50 mm; the number of antifreezing cycle is not less than 150, and the lowest temperature and the highest temperature in the antifreezing cycle are respectively -18 DEG C and 35 DEG C. The concrete of the invention can meet the concrete performance requirements for a skating rink in Shanghai oriental sports center with respect to high slump retaining performance, self-compacting performance, strength performance, high antifreezing performance, and the like.

The invention provides a hyperbranched polymer, a hyperbranched polycarboxylic acid-series super plasticizer and a preparation method thereof. The preparation method comprises the following steps of: undergoing an addition reaction and an ammonolysis reaction on alkenyl amine, polymethylmethacrylate, ethylene diamine and 2-acrylamide-2-sodium methylacrylsulfonate serving as raw materials to obtain a hyperbranched polymer with a structure shown as a formula (I), (II), (III) or (IV); undergoing a polymerization reaction on the hyperbranched polymer, an esterification monomer and a crosslinking agent; and preparing a hyperbranched polycarboxylic acid-series super plasticizer with a two-step process. The preparation method provided by the invention has the advantages of simple process, easiness for controlling a preparing process and operating, readily-available raw materials, low production cost and suitability for industrial production. Due to the adoption of the hyperbranched polycarboxylic acid-series super plasticizer, the comprehensive performance of concrete is improved. As proved by an experiment result, the hyperbranched polycarboxylic acid super plasticizer provided by the invention has high slump loss resistance, high water-reducing rate and high compressive strength.

The invention relates to a structural formula and a preparation method of a phosphate-based high slump loss resistant type polycarboxylate high-performance water reducing agent. The method includes: performing esterification reaction of alcohol and a mixture of one or more of unsaturated acids and unsaturated acid anhydrides, performing phosphorylation of a phosphatizing agent and prepared unsaturated acid ester, subjecting prepared phosphate and isobutene or TPEG, a chain transfer agent and a mixture of one or more of unsaturated acids and unsaturated acid derivatives to free radical polymerization reaction at the normal temperature, and after reaction is finished, adding an alkali solution to regulate a pH to be 7-9 to obtain the phosphate-based high slump loss resistant type polycarboxylate high-performance water reducing agent. The water reducing agent has the advantages of excellent performances, low admixing quantity, high water reducing rate, excellent slump loss resistance, high cement adaptability, insensitivity to mud content of concrete materials and the like.

The invention provides a super slump type polycarboxylate water reducing agent for bored pile concrete. The water reducing agent is in a liquid state and comprises the following ingredients: sodium oleate, water reducing type polycarboxylate plasticizer, slump type polycarboxylate plasticizer, hydroxyethylidene diphosphonic acid, 2-acrylamide-2-methylpropanesulfonic acid/itaconic acid/acrylic acid terpolymer, hydroxypropyl methyl cellulose or hydroxyethyl methyl cellulose, air entraining agent and triisopropanolamine. The super slump type polycarboxylate water reducing agent for bored pile concrete provided by the invention has the following beneficial effects that by using the super slump type polycarboxylate water reducing agent, the bored pile concrete is good in homogeneity, the static bleeding rate of the bored pile concrete can be generally less than 1%, stable working performance can be maintained within a long time span, meeting the working property of concrete after 0.5-5.0h can be met by adjusting the formulation and dosage and improving the compressive strength ratio of the concrete, and the 28 d strength can be more than 130% of that of benchmark concrete. The invention further provides a preparation method of the super slump type polycarboxylate water reducing agent for bored pile concrete.

The invention discloses a method for preparing a polycarboxylic acid grafted copolymer superplasticizer. In the method, the preparation is implemented at the low temperature of 5-30 DEG C; a used initiating system is a complex initiating system which adopts the combination of one initiator I and various reducers R, or one reducer R and various initiators I or various initiators I and various reducers R, wherein the initiator (s) I is (are) selected from hydrogen peroxide, persulfate salt LS2O8 and a water-soluble azo initiator W, and the reducer (s) R is (are) selected from ascorbic acid and certain kinds of inorganic salt. The preparation method is simple, excellent in repetition stability and low in cost, does not require heating, and avoids toxicity and pollution; the prepared superplasticizer is high in water-reducing rate, and excellent in adaptability and slump-retaining capability, thereby being suitable for popularization and application.

The invention belongs to the technical field of concrete additives, and discloses a polyether-amide type polycarboxylic high-efficiency water reducer and a preparation method thereof. The polyether-amide type polycarboxylic high-efficiency water reducer adopts the following structure, wherein R is H or CH3, x=5-15, y=20-50, z=8-16, a=20-150, b=30-1200, and c=10-150. The preparation method of the polyether-amide type polycarboxylic high-efficiency water reducer comprises the following steps of: firstly reacting polyetheramine and acyl chloride monomer to obtain a polyether amine monomer; then adding a polyoxyethylene ether monomer and a carboxyl monomer to carry out radical copolymerization in a water solution under the condition of an initiating agent and a chain transfer agent so as to obtain the polyether-amide type polycarboxylic high-efficiency water reducer with good dispersibility and slump retaining property. The preparation method disclosed by the invention is simple, low in raw material cost and outstanding in economic benefit and environmental benefit without using an organic solvent.

The invention provides a concrete polycarboxylate water reducer, which is shown in the formula (A), wherein R1 is alkyl having 1 to 10 carbon atoms, R2 is alkyl having 1 to 10 hydrogen or carbon atoms, R3 is H or COOH, and R4 is H or CH3. The water reducer has stable performance and high water-reducing rate and slump retention. The invention also provides a preparation method of the water reducer, which has the advantages of simple process, convenience for operation, environmental friendliness, low energy consumption and the like.

This invention relates to a method for preparing high-performance aminosulfonic acid-series water reducer with polyether-grafted comb-like molecular structure for cement. The high-performance aminosulfonic acid-series water reducer is prepared from: p-aminobenzenesulfonic acid 100 parts, NaOH 115-140 parts, phenol 10-100 parts, modified polyether 0-90 parts, formaldehyde 300-600 parts, and water 3000-10000 parts. The method comprises: dissolving p-aminobenzenesulfonic acid, NaOH, phenol and modified polyether in water at 5-50 deg.C, heating to 50-120 deg.C, dropping formaldehyde, and keeping the temperature for 1-9 h. The high-performance aminosulfonic acid-series water reducer can effectively inhibit the collapse loss of concrete. The high-performance aminosulfonic acid-series water reducer has high workability, and water cannot infiltrate into concrete containing it.

The invention provides a preparation method of a slushing agent for concrete. The preparation method comprises the following steps in sequence: implementing the first reaction between maleic anhydride and hydroxypropyl methyl cellulose in glacial acetic acid under the catalysis of acetate, so as to obtain the hydroxypropyl methyl cellulose monomaleate; and carrying out free radical polymerization between methyl allyl polyoxyethylene ether, acrylic acid solution and hydroxypropyl methyl cellulose monomaleate under an oxidentive-reductive initiation system, so as to obtain the slushing agent for concrete. According to the slushing agent for concrete, prepared by the preparation method provided by the invention, the molecular structure contains the hydroxypropyl methyl cellulose molecular structure unit, so that the macromolecules of the slushing agent can be entangled with each other to form a net-shaped structure to wrap cement and water for effectively preventing the moisture in the mortar from evaporating, and as a result, the slump keeping property is good. The invention also provides the slushing agent for concrete, and the slushing agent for concrete has the structure as shown in formula (1).

The invention discloses a preparation method of a water retaining agent. The preparation method comprises the following steps: carrying out an aqueous phase radical polymerization reaction on unsaturated amide micro-monomers, unsaturated sulphonic acid micro-monomers and unsaturated polyether macromers or unsaturated ester macromonomers under the coaction of an oxidation-reduction system composed of an initiator and a reducing agent to obtain a copolymerization product, regulating the pH value to 6-7 after the reaction, and adding water to obtain the water retaining agent with mass concentration of 1-60%. The preparation method disclosed by the invention is used for adjusting the product properties by controlling the monomer proportion, the temperature and the dosage of the initiator and the reducing agent, the reaction speed is high, the efficiency is high, no organic solvent is used, no toxin or pollution is generated, and the operation is simple. The unsaturated macromonomers are introduced into the prepared concrete/mortar water retaining agent to ensure excellent water retaining property and obviously perfect such stirring states of the concrete/mortar as bleeding/separation and the like without generating such adverse effects as strength and the like, meanwhile, the water retaining agent can be compounded with a polycarboxylic acid water reducing agent at any proportion to ensure good intermiscibility. The product performance is stable.

The invention relates to an anticorrosive composite polycarboxylate superplasticizer with high slump loss resistance, and a preparation method and application thereof. The composite polycarboxylate superplasticizer comprises, by mass, 40 to 55% of mother liquor of a polycarboxylate superplasticizer, 4 to 7% of sodium gluconate, 0.15 to 0.3% of an air entraining agent, 0.1 to 0.25% of an antifoaming agent, 0.05 to 0.2% of an emulsifying agent and 0.1 to 0.3% of an anticorrosive bactericide, with the balance being water, wherein the mass percents of every component sum to 100%. The composite polycarboxylate superplasticizer is prepared by placing the mother liquor of the polycarboxylate superplasticizer, sodium gluconate, the air entraining agent, the antifoaming agent, the anticorrosive bactericide and the water in a container together according to the above-mentioned mass percents under the conditions of normal temperature and normal pressure and carrying out uniform mixing under stirring. In use, the composite polycarboxylate superplasticizer is added into a concrete cementing material according to a mass ratio of the composite polycarboxylate superplasticizer to the concrete cementing material of 0.1-0.15: 100. Compared with the prior art, the composite polycarboxylate superplasticizer provided by the invention has the advantages of convenience in usage, stable performance, no phenomena of mildew, smelliness and layering due to long-term storage, capacity of introducing small bubbles when used in fresh mixed concrete, and excellent water-reducing and slump-retaining performances.