阅读说明：本技术 一种用无皂乳液聚合法制备的固片状聚羧酸减水剂及方法 (Solid sheet-shaped polycarboxylate superplasticizer prepared by soap-free emulsion polymerization method and method ) 是由 柯凯 姚恒 于 2019-11-19 设计创作，主要内容包括：本发明提供了一种用无皂乳液聚合法制备的固体聚羧酸减水剂及方法。各组分的重量份为：无皂乳化剂羧酸类亲水单体：7-14份；无皂乳化剂氟代功能单体：18-25份；引发剂a：0.56-0.74份；链转移剂a：0.43-0.87份；不饱和二元羧酸：60-100份；聚醚大单体：770-900份；不饱和磺酸类小单体：10-30份；pH调节剂：3.3-5.4份；过氧化物类引发剂：2.0-4.5份；链转移剂b：2.4-3.7份；引发剂b：2.0-6.0份；链转移剂c：2.8-4.6份；所述方法按如下操作步骤进行：1、制备无皂聚合物；2、制备A、B溶液；3、滴加A、B溶液；4、制备固片状聚羧酸减水剂。本发明制备的固体聚羧酸减水剂产品具有环境污染小、反应条件温、高固含、较强的减水分散效果,适用于任何型号的水泥。(The invention provides a solid polycarboxylic acid water reducing agent prepared by a soap-free emulsion polymerization method and a method thereof. The weight parts of each component are as follows: soap-free emulsifier carboxylic hydrophilic monomer: 7-14 parts; the non-soap emulsifier fluoro functional monomer: 18-25 parts; an initiator a: 0.56-0.74 portion; chain transfer agent a: 0.43-0.87 parts; unsaturated dicarboxylic acids: 60-100 parts; polyether macromonomer: 770-900 parts; unsaturated sulfonic acid small monomer: 10-30 parts; pH regulator: 3.3-5.4 parts; peroxide initiator: 2.0-4.5 parts; chain transfer agent b: 2.4-3.7 parts; an initiator b: 2.0-6.0 parts; chain transfer agent c: 2.8-4.6 parts; the method comprises the following operation steps: 1. preparing a soap-free polymer; 2. preparing A, B solution; 3. a, B solution is added dropwise; 4. preparing the solid sheet type polycarboxylate superplasticizer. The solid polycarboxylate superplasticizer prepared by the invention has the advantages of small environmental pollution, mild reaction conditions, high solid content and strong water reducing and dispersing effects, and is suitable for cement of any type.)

1. A solid sheet-shaped polycarboxylate superplasticizer prepared by a soap-free emulsion polymerization method is characterized in that: the compound fertilizer is prepared from the following components in parts by weight, wherein the total parts by weight of the raw materials are 1000 parts, and the components in parts by weight are as follows:

soap-free emulsifier carboxylic hydrophilic monomer: 7-14 parts; an initiator a: 0.56-0.74 portion;

the non-soap emulsifier fluoro functional monomer: 18-25 parts; chain transfer agent a: 0.43-0.87 parts;

unsaturated dicarboxylic acids: 60-100 parts; polyether macromonomer: 770-900 parts;

unsaturated sulfonic acid small monomer: 10-30 parts; pH regulator: 3.3-5.4 parts;

peroxide initiator: 2.0-4.5 parts; chain transfer agent b: 2.4-3.7 parts;

an initiator b: 2.0-6.0 parts; chain transfer agent c: 2.8 to 4.6 portions.

2. The solid sheet polycarboxylate superplasticizer prepared by the soap-free emulsion polymerization method according to claim 1, characterized in that: the carboxylic acid hydrophilic monomer of the soap-free emulsifier is one or more of itaconic acid, fumaric acid, maleic acid and aconitic acid.

3. The solid sheet polycarboxylate superplasticizer prepared by the soap-free emulsion polymerization method according to claim 1, characterized in that: the fluorinated functional monomer of the soap-free emulsifier is one or more of 2,2, 2-trifluoroethyl methacrylate, trifluoroethyl acrylate, perfluorooctyl ethyl acrylate and perfluorobutyl ethyl acrylate.

4. The solid sheet polycarboxylate superplasticizer prepared by the soap-free emulsion polymerization method according to claim 1, characterized in that: the initiator comprises an initiator a and an initiator b; the initiator a is one or more of azodiisobutyronitrile, lauroyl peroxide and tert-butyl peroxypivalate; the initiator b is one or more of azodiisoheptonitrile, diisopropyl peroxydicarbonate and dicyclohexyl peroxydicarbonate, and the initiation rate of the initiator b is higher than that of the initiator a.

5. The solid sheet polycarboxylate superplasticizer prepared by the soap-free emulsion polymerization method according to claim 1, characterized in that: the chain transfer agent comprises a chain transfer agent a, a chain transfer agent b and a chain transfer agent c; the chain transfer agent a is sodium hypophosphite; the chain transfer agent b is one or more of sodium hypophosphite, sodium formate and sodium polyphosphate; the chain transfer agent c is one or more of aliphatic mercaptan, dodecyl mercaptan, dithioester, mercaptopropionic acid and mercaptoacetic acid.

6. The solid sheet polycarboxylate superplasticizer prepared by the soap-free emulsion polymerization method according to claim 1, characterized in that: the unsaturated dicarboxylic acid is one or two of itaconic acid and fumaric acid.

7. The solid sheet polycarboxylate superplasticizer prepared by the soap-free emulsion polymerization method according to claim 1, characterized in that: the polyether macromonomer is composed of one or more of methyl allyl polyoxyethylene ether, allyl polyoxyethylene ether and prenol polyoxyethylene ether.

8. The solid sheet polycarboxylate superplasticizer prepared by the soap-free emulsion polymerization method according to claim 1, characterized in that: the unsaturated sulfonic acid small monomer is one or more of sodium vinyl sulfonate, sodium allyl sulfonate, sodium methyl propylene sulfonate and sodium styrene sulfonate.

9. The solid sheet polycarboxylate superplasticizer prepared by the soap-free emulsion polymerization method according to claim 1, characterized in that: the organic peroxide initiator is one or more of cumene hydroperoxide, tert-butyl hydroperoxide, dicumyl peroxide, dibenzoyl peroxide, lauroyl peroxide, tert-butyl peroxypivalate, diisopropyl peroxydicarbonate and dicyclohexyl peroxydicarbonate.

10. The method for preparing the solid-sheet polycarboxylate superplasticizer by the soap-free emulsion polymerization method according to claim 1, wherein the method comprises the following steps: the method comprises the following steps:

(1) preparation of soap-free polymers: directly adding 20-40 parts of water, 7-14 parts of carboxylic acid hydrophilic monomer of soap-free emulsifier, 18-25 parts of fluorinated functional monomer of soap-free emulsifier, 0.56-0.74 part of initiator a and 0.56-0.74 part of chain transfer agent a into a three-neck flask with a stirring device, uniformly stirring, controlling the temperature to react for 1.0-2.0 hours at 55-75 ℃, and then preserving the heat for 2.0-3.0 hours to obtain a soap-free polymer for later use;

(2) preparation of A, B solution: preparing 770-900 parts of polyether macromonomer, 60-100 parts of unsaturated dicarboxylic acid, 2.4-3.7 parts of chain transfer agent b, 15-30 parts of unsaturated sulfoacid small monomer and 3.3-5.4 parts of pH regulator into solution A for later use; preparing solution B from 2.0-4.5 parts of peroxide initiator, 2.0-6.0 parts of initiator B, 2.8-4.6 parts of chain transfer agent c and 15-30 parts of water for later use;

(3) dropwise addition of A, B solution: controlling the temperature of the soap-free polymer obtained in the step (1) to 45-55 ℃, slowly dripping the solution A and the solution B into a three-neck flask at the same time, wherein the dripping time of the solution A is 2-4.5 hours, the dripping time of the solution B is 3.2-5.4 hours, stirring while dripping, and preserving the temperature for 1 hour after dripping is finished;

(4) preparing a solid sheet type polycarboxylate superplasticizer: and (4) raising the temperature of the solution obtained in the step (3), controlling the temperature to 55-70 ℃, evaporating the residual water, removing the redundant initiator, and finally obtaining the solid, namely the prepared solid sheet-shaped polycarboxylate superplasticizer.

Technical Field

The invention relates to the technical field of building materials and water reducing agents, in particular to a solid sheet-shaped polycarboxylic acid water reducing agent prepared by a soap-free emulsion polymerization method and a method thereof.

Background

The polycarboxylate superplasticizer is used as a fifth component of modern concrete, and has been widely applied to the technical field of concrete engineering by virtue of the advantages of excellent low dosage, high slump, large freedom of molecular design and the like. At present, the widely used polycarboxylic acid water reducing agent is mostly a solution product with the concentration of 10-50%. Due to the fact that part of construction sites are far away, the lower solid content can improve the transportation cost; in addition, the wide popularization and application of the dry powder mortar also puts urgent demands on the production and application of the solid polycarboxylic acid water reducing agent. When the water reducing agent is used in the production process of products such as dry powder mortar, grouting material and the like, the solid water reducing agent must be selected morphologically. The solid state is not limited to powder, so that the water-soluble film is convenient to store and has good water solubility.

Soap-free emulsion polymerization is a new polymerization reaction technology developed on the basis of traditional emulsion polymerization, and refers to a polymerization process of emulsion residue in which no or a small amount of emulsifier is added in the reaction process. The emulsion particles with clean surfaces and single dispersion can be obtained without adding conventional emulsifying agents, and the pollution of the emulsifying agents to the environment is eliminated. The soap-free emulsion polymerization overcomes the defects of the traditional emulsion polymerization, and the particle surface can be provided with various functional groups through particle design, so that the soap-free emulsion polymerization is widely applied to the fields of biology, medicine, chemical industry and the like.

Patent CN106749970A discloses a solid sheet-like polycarboxylic acid water reducing agent and a preparation method thereof. The method comprises the following specific steps: placing 805-845 parts of polyether macromonomer in a reaction kettle, heating and stirring until the polyether macromonomer is completely dissolved; the stable temperature is 65-75 ℃, 5-10 parts of weak chain transfer agent, 2.0-4.5 parts of organic peroxy initiator, 5.5-10.5 parts of unsaturated dicarboxylic acid and 5.0-11.5 parts of unsaturated sulfonic acid small monomer are added at one time; then, adding 5-10 parts of concentrated sulfuric acid, and adjusting the pH value of the base solution to 5.0; beginning to dropwise add a mixed solution of 35-65 parts of acrylic acid, 70-115 parts of hydroxyalkyl acrylate and 2.8-4.6 parts of strong chain transfer agent, and adding an initiator twice in the dropwise adding process; after the dropwise addition is finished, curing is carried out for 1-2h, 5.5-12.0 parts of neutralizing agent is added, and the mixture is cooled and sliced to obtain a finished product.

CN104628969A discloses a preparation method of a slow-release solid polycarboxylic acid water reducing agent, which comprises the steps of firstly utilizing amine organic micromolecules to pretreat carboxylic acid small monomers containing unsaturated double bonds; then heating and melting the pretreated unsaturated acrylic small monomer and unsaturated polyoxyethylene ether large monomer, dripping the unsaturated ester small monomer under the action of an initiator and a chain transfer agent, and placing the mixture in an anhydrous organic solvent-free environment in the reaction process to perform bulk polymerization reaction to obtain the unsaturated acrylic small monomer and the unsaturated polyoxyethylene ether large monomer.

Patent CN 106279565A discloses a method for producing a solid polycarboxylic acid water reducer by using a double-excitation system and a preparation method thereof, wherein the solid polycarboxylic acid water reducer is produced by using two free radical polymerization processes of an oxidation-reduction excitation system and bulk polymerization. The solid polycarboxylate superplasticizer produced by the process is a solid polycarboxylate superplasticizer which is formed by carrying out molecular polymerization and grafting on unsaturated carboxylic acid and unsaturated polyoxyethylene ether macromonomer under the action of an initiator and a chain transfer agent and has a comb-type molecular structure same as that of a conventional liquid polycarboxylate superplasticizer. The process method adopts a double-excitation process, has flexible molecular structure, can obtain products with different properties by introducing different groups, has strong adaptability to concrete floor materials, does not contain any volatile solvent in the prepared solid polycarboxylate superplasticizer, and can prepare the flaky or powdery solid polycarboxylate superplasticizer by condensation slicing technology or mechanical crushing.

Different from the patents, the solid sheet polycarboxylate superplasticizer is prepared by adopting a soap-free emulsion polymerization method, and the preparation method has the advantages of high polymerization speed, few reaction steps, small environmental pollution and mild reaction conditions; and the prepared product has excellent performances of high solid content, strong water-reducing dispersion effect and the like.

Disclosure of Invention

The invention aims to provide a solid polycarboxylic acid water reducing agent prepared by a soap-free emulsion polymerization method and a method thereof.

The invention adopts the design idea of adopting a soap-free emulsion polymerization method for preparation, carboxyl monomers and polyether macromonomers are used as raw materials, the soap-free emulsion polymerization method is adopted, the pH value of the reaction environment is controlled to be neutral by using a pH regulator, a soap-free emulsifier carboxylic acid hydrophilic monomer, a soap-free emulsifier fluoro functional monomer and an initiator a are reacted to synthesize a soap-free emulsifier, the soap-free polymer is reacted with other raw materials to synthesize a solid sheet-shaped polycarboxylic acid water reducing agent, and a self-made emulsifier is selected to reduce the viscosity of a reaction system and improve the polymerization efficiency. The method comprises the steps of ensuring constant reaction temperature by using a soap-free emulsion polymerization method, controlling reaction rate, and dropwise adding an initiator into carboxylic acid hydrophilic monomers and fluoro functional monomers to prepare a soap-free emulsifier, wherein the soap-free emulsifier can disperse the monomers into tiny polyether macromonomer beads to form emulsion, and can also form micelles and solubilizing micelles to form emulsion particles serving as reaction sites according to a micelle nucleation mechanism. The solid sheet-shaped polycarboxylate superplasticizer provided by the invention utilizes the polymerization reaction of a macromonomer to increase the molecular chain, and introduces a proper amount of hydrophilic groups in the reaction process of polycarboxylic acid to ensure the dispersibility of the synthesized polycarboxylic acid and improve the water reducing effect; promoting the practicability, the durability and the slump retaining property of the polycarboxylic acid water reducing agent.

In order to achieve the purpose, the technical scheme of the invention is as follows:

a solid sheet-shaped polycarboxylate superplasticizer prepared by a soap-free emulsion polymerization method comprises the following components in parts by weight, wherein the raw materials comprise, by weight, 1000 parts:

soap-free emulsifier carboxylic hydrophilic monomer: 7-14 parts; the non-soap emulsifier fluoro functional monomer: 18-25 parts; an initiator a: 0.56-0.74 portion; chain transfer agent a: 0.43-0.87 parts; unsaturated dicarboxylic acids: 60-100 parts; polyether macromonomer: 770-900 parts; unsaturated sulfonic acid small monomer: 10-30 parts; pH regulator: 3.3-5.4 parts; peroxide initiator: 2.0-4.5 parts; chain transfer agent b: 2.4-3.7 parts; an initiator b: 2.0-6.0 parts; chain transfer agent c: 2.8-4.6 parts;

the carboxylic acid hydrophilic monomer of the soap-free emulsifier is one or more of itaconic acid, fumaric acid, maleic acid and aconitic acid; preferably a composition of itaconic acid and maleic acid in a mass ratio of 1: 1.

The soap-free emulsifier fluoro functional monomer is any one or more of 2,2, 2-trifluoroethyl methacrylate, trifluoroethyl acrylate, perfluorooctyl ethyl acrylate and perfluorobutyl ethyl acrylate; a composition of 2,2, 2-trifluoroethyl methacrylate and perfluorobutylethyl acrylate in a mass ratio of 1:1 is preferred.

The initiator comprises an initiator a and an initiator b; the initiator a is any one or more of azodiisobutyronitrile, lauroyl peroxide and tert-butyl peroxypivalate; preferably a composition of tert-butyl peroxypivalate and lauroyl peroxide in a mass ratio of 1:1, wherein the initiator b is one or more of azodiisoheptanonitrile, diisopropyl peroxydicarbonate and dicyclohexyl peroxydicarbonate; most preferred is azobisisoheptonitrile.

The chain transfer agent comprises a chain transfer agent a, a chain transfer agent b and a chain transfer agent c; the chain transfer agent a is sodium hypophosphite; the chain transfer agent b is any one or more of sodium hypophosphite, sodium formate and sodium polyphosphate; preferably sodium polyphosphate, and the chain transfer agent c is any one or more of aliphatic mercaptan, dodecyl mercaptan, dithioester, mercaptopropionic acid and mercaptoacetic acid; a composition of thioglycolic acid and mercaptopropionic acid in a mass ratio of 1:1 is preferred.

The unsaturated dicarboxylic acid is one or two of itaconic acid and fumaric acid; preferably itaconic acid.

The polyether macromonomer is one or more of methyl allyl polyoxyethylene ether, allyl polyoxyethylene ether and prenol polyoxyethylene ether; preferably a combination of allyl polyoxyethylene ether and vinyl butyl ether polyoxyethylene ether in a mass ratio of 1: 2.

The unsaturated sulfonic acid small monomer is any one or more of sodium vinyl sulfonate, sodium allyl sulfonate, sodium methyl propylene sulfonate and sodium styrene sulfonate; sodium styrene sulfonate is preferred.

The pH regulator is any one or more of sodium methoxide, ethanolamine, triethanolamine and triisopropanolamine; a composition of sodium methoxide and ethanolamine in a mass ratio of 1:1 is preferred.

The organic peroxide initiator is any one or more of cumene hydroperoxide, tert-butyl hydroperoxide, dicumyl peroxide, dibenzoyl peroxide, lauroyl peroxide, tert-butyl peroxypivalate, diisopropyl peroxydicarbonate and dicyclohexyl peroxydicarbonate; preferably a composition of peroxydodecanyl and cumene hydroperoxide in a mass ratio of 2: 1.

A method for preparing a solid sheet-shaped polycarboxylate superplasticizer by a soap-free emulsion polymerization method comprises the following operation steps:

1. preparation of soap-free polymers: directly adding 20-40 parts of water, 7-14 parts of carboxylic acid hydrophilic monomer of soap-free emulsifier, 18-25 parts of fluorinated functional monomer of soap-free emulsifier, 0.56-0.74 part of initiator a and 0.56-0.74 part of chain transfer agent a into a three-neck flask with a stirring device, uniformly stirring, controlling the temperature to react for 1.0-2.0 hours at 55-75 ℃, and then preserving the heat for 2.0-3.0 hours to obtain a soap-free polymer for later use;

2. preparation of A, B solution: preparing 770-900 parts of polyether macromonomer, 60-100 parts of unsaturated dicarboxylic acid, 2.4-3.7 parts of chain transfer agent b, 15-30 parts of unsaturated sulfoacid small monomer and 3.3-5.4 parts of pH regulator into solution A for later use; preparing solution B from 2.0-4.5 parts of peroxide initiator, 2.0-6.0 parts of initiator B, 2.8-4.6 parts of chain transfer agent c and 15-30 parts of water for later use;

3. dropwise addition of A, B solution: cooling the soap-free polymer obtained in the step 1 to 45-55 ℃, slowly dripping the solution A and the solution B into a three-neck flask at the same time, wherein the dripping time of the solution A is 2-4.5 hours, the dripping time of the solution B is 3.2-5.4 hours, stirring while dripping, and preserving heat for 1 hour after dripping is finished;

4. preparing a solid sheet type polycarboxylate superplasticizer: and (4) raising the temperature of the solution obtained in the step (3), controlling the temperature to 55-70 ℃, evaporating the residual water, and removing the redundant initiator to obtain a solid, namely the prepared solid sheet-shaped polycarboxylate superplasticizer.

Compared with the prior art, the invention has the beneficial effects that:

the solid sheet polycarboxylate superplasticizer is prepared by adopting a soap-free emulsion polymerization method, a certain proportion of polyether macromonomer and unsaturated dicarboxylic acid are used as raw materials, a soap-free emulsion polymerization method is adopted, meanwhile, a pH value of a reaction environment is controlled to be neutral by using a pH regulator, the soap-free unsaturated dicarboxylic acid, a soap-free emulsifier fluoro functional monomer and an initiator a are reacted to synthesize a soap-free emulsifier, the viscosity of a reaction system is reduced, the polymerization efficiency is improved, the stability of the emulsion is enhanced, the monomer can be dispersed into tiny polyether macromonomer bead drops to form the emulsion, micelles and solubilized micelles can be formed, and emulsion particles serving as reaction sites are formed according to a micelle nucleation mechanism. The soap-free emulsion polymerization preparation method ensures constant reaction temperature, controls reasonable reaction rate, has the advantages of high polymerization speed, few reaction steps, small environmental pollution, mild reaction conditions and the like, and the obtained product has high solid content and strong water-reducing dispersion effect and is suitable for any cement. The specific technical effects are as follows:

1. when the concrete is used, the consumption of gel materials such as cement and the like and water is reduced, the water reducing property, the slump retaining property and the strength of the concrete are not influenced, and the transportation cost is reduced;

2. the solid sheet polycarboxylate superplasticizer prepared by the soap-free emulsion polymerization method has the advantages of high polymerization speed, few reaction steps, little environmental pollution, mild reaction conditions and the like;

3. according to the solid sheet-shaped polycarboxylate superplasticizer prepared by the invention, a molecular chain is increased by utilizing the polymerization reaction of a macromonomer, and a proper amount of hydrophilic groups are introduced in the reaction process of the polycarboxylate to ensure the dispersibility of the synthesized polycarboxylate, so that the water reducing effect is improved, and the durability and slump retaining property are increased;

4. the solid sheet-shaped polycarboxylate superplasticizer prepared by the invention has good compatibility with various cements, the slump retentivity of concrete is good, and the construction time of concrete is prolonged;

5. the solid sheet polycarboxylate superplasticizer prepared by the invention can protect the separation of raw materials, thereby producing concrete with consistent quality; the high plasticizing effect is exerted under the condition of low doping amount, the fluidity is kept good, and the content of harmful substances is low;

6. according to the solid sheet-shaped polycarboxylate superplasticizer prepared by the invention, two different initiators adopted at different temperatures are more in accordance with activities required by two polymerization reactions, so that a polymer synthesized by the two polymerization reactions has a better effect;

7. after the soap-free polymer is synthesized in the preparation process, the heat preservation is carried out, so that the soap-free polymer keeps the highest activity, and then the soap-free polymer is reacted with other raw materials, so that the activity of the soap-free polymer is fully utilized.

Detailed Description

The technical solution of the present invention is further clearly and completely described by the following examples.

Example 1

A solid sheet-shaped polycarboxylate superplasticizer prepared by a soap-free emulsion polymerization method is polymerized from the following components in parts by weight, wherein the total mass is 1000 parts, and the components in parts by weight are as follows:

the composition of itaconic acid and maleic acid with the mass ratio of 1: 10 parts of (A); the mass ratio is 1:2, 2, 2-trifluoroethyl methacrylate and trifluoroethyl acrylate: 22 parts of (A); azobisisobutyronitrile: 0.6 part; sodium hypophosphite: 0.64 part; the composition of itaconic acid and fumaric acid with the mass ratio of 1: 80 parts of a mixture; the composition of the allyl polyoxyethylene ether and the vinyl butyl ether polyoxyethylene ether in the mass ratio of 1:2 comprises the following components: 850 parts of (a); the composition of sodium vinyl sulfonate and sodium propenyl sulfonate with the mass ratio of 2: 3: 20 parts of (1); triisopropanolamine: 4.2 parts of a mixture; a composition of peroxydodecanyl and cumene hydroperoxide in a mass ratio of 1: 2:3 parts of a mixture; the composition of sodium hypophosphite and sodium formate with the mass ratio of 1:1 comprises the following components: 2.7 parts; azobisisoheptonitrile: 4.0 parts of (B); a composition of aliphatic thiol and dithioester in a mass ratio of 2: 1: 2.86 parts.

A method for preparing a solid sheet-shaped polycarboxylate superplasticizer by a soap-free emulsion polymerization method comprises the following operation steps:

1. preparation of soap-free polymers: 20 parts of water, 10 parts of a composition of itaconic acid and maleic acid with a mass ratio of 1:1, 22 parts of a composition of 2,2, 2-trifluoroethyl methacrylate and trifluoroethyl acrylate with a mass ratio of 1:2, 0.6 part of azobisisobutyronitrile, 0.64 part of sodium hypophosphite are directly added into a three-neck flask with a stirring device, after uniform stirring, the temperature is controlled to react for 1.5 hours at 50 ℃, and then heat preservation is carried out for 3.0 hours, so as to obtain a soap-free polymer for later use;

2. preparation of A, B solution: preparing 850 parts of a composition of allyl polyoxyethylene ether and vinyl butyl ether polyoxyethylene ether in a mass ratio of 1:2, 80 parts of a composition of itaconic acid and fumaric acid in a mass ratio of 1:1, 2.7 parts of a composition of sodium vinyl sulfonate and sodium allyl sulfonate in a mass ratio of 2:3, 20 parts of a composition of sodium hypophosphite and sodium formate in a mass ratio of 1:1 and 4.2 parts of triisopropanolamine into a solution A for later use; preparing 3 parts of a composition of peroxydodecanoyl and cumene hydroperoxide with a mass ratio of 1:2, 4 parts of azobisisoheptonitrile, 2.86 parts of a composition of aliphatic thiol and dithioester with a mass ratio of 2:1 and 15 parts of water into a solution B for later use;

3. dropwise addition of A, B solution: cooling the soap-free polymer obtained in the step (1) to 50 ℃, slowly dripping the solution A and the solution B into a three-neck flask at the same time, wherein the dripping time of the solution A is 2.7 hours, the dripping time of the solution B is 3.2 hours, the dripping time of the solution B is 0.5 hour longer than that of the solution A, stirring while dripping, and preserving heat for 1 hour after dripping is finished;

4. preparing a solid sheet type polycarboxylate superplasticizer: and (4) raising the temperature of the solution obtained in the step (3), evaporating the residual water, controlling the temperature to 55 ℃, and removing the redundant initiator to obtain a solid, namely the prepared solid sheet-shaped polycarboxylate superplasticizer.

Example 2

A solid sheet-shaped polycarboxylate superplasticizer prepared by a soap-free emulsion polymerization method is polymerized from the following components in parts by weight, wherein the total mass is 1000 parts, and the components in parts by weight are as follows:

the composition of itaconic acid and maleic acid with the mass ratio of 1: 14 parts of (1); perfluorobutylethyl acrylate: 22 parts of (A); tert-butyl peroxypivalate: 0.6 part; sodium hypophosphite: 0.54 part; itaconic acid: 70 parts of (B); the composition of the allyl polyoxyethylene ether and the vinyl butyl ether polyoxyethylene ether in the mass ratio of 1:2 comprises the following components: 860 parts of; sodium styrene sulfonate: 18 parts of a mixture; the mass ratio of the sodium methoxide to the ethanolamine is 1: 4.2 parts of a mixture; a composition of peroxydodecanyl and cumene hydroperoxide in a mass ratio of 1: 2: 2 parts of (1); sodium polyphosphate: 2.6 parts; azobisisoheptonitrile: 3.0 parts of (B); thioglycolic acid: 3.06 parts.

A method for preparing a solid sheet-shaped polycarboxylate superplasticizer by a soap-free emulsion polymerization method comprises the following operation steps:

1. preparation of soap-free polymers: 20 parts of water, 14 parts of a composition of itaconic acid and maleic acid in a mass ratio of 1:1, 22 parts of perfluorobutyl ethyl acrylate, 0.6 part of tert-butyl peroxypivalate and 0.54 part of sodium hypophosphite are directly added into a three-neck flask with a stirring device, after uniform stirring, the temperature is controlled to react for 1.8 hours at 70 ℃, and then the temperature is kept for 2.5 hours to obtain a soap-free polymer for later use;

2. preparation of A, B solution: 860 parts of a composition of allyl polyoxyethylene ether and vinyl butyl ether polyoxyethylene ether in a mass ratio of 1:2, 70 parts of itaconic acid, 2.6 parts of sodium polyphosphate, 18 parts of sodium styrene sulfonate and 4.2 parts of a composition of sodium methoxide and ethanolamine in a mass ratio of 1:1 are prepared into solution A for later use; preparing 2 parts of a composition of peroxydodecanoyl and cumene hydroperoxide with the mass ratio of 1:2, 3.0 parts of azobisisonitrile, 3.06 parts of thioglycolic acid and 15 parts of water into a solution B for later use;

3. dropwise addition of A, B solution: cooling the soap-free polymer obtained in the step (1) to 45 ℃, slowly dripping the solution A and the solution B into a three-neck flask at the same time, wherein the dripping time of the solution A is 3.0 hours, the dripping time of the solution B is 4.5 hours, the dripping time of the solution B is 1 hour longer than that of the solution A, stirring while dripping, and preserving heat for 1 hour after dripping is finished;

4. preparing a solid sheet type polycarboxylate superplasticizer: and (4) raising the temperature of the solution obtained in the step (3), controlling the temperature to 60 ℃, evaporating the residual water, and removing the redundant initiator to obtain a solid, namely the prepared solid sheet-shaped polycarboxylate superplasticizer.

Example 3

A solid sheet-shaped polycarboxylate superplasticizer prepared by a soap-free emulsion polymerization method is polymerized from the following components in parts by weight, wherein the total mass is 1000 parts, and the components in parts by weight are as follows:

the composition of itaconic acid and maleic acid with the mass ratio of 1: 11 parts of (1); 2,2, 2-trifluoroethyl methacrylate: 25 parts of (1); tert-butyl peroxypivalate: 0.7 part; sodium hypophosphite: 0.54 part; itaconic acid: 69 parts of (1); the composition of the allyl polyoxyethylene ether and the vinyl butyl ether polyoxyethylene ether in the mass ratio of 1:2 comprises the following components: 858 parts of; sodium styrene sulfonate: 18 parts of a mixture; the mass ratio of the sodium methoxide to the ethanolamine is 1: 4.1 parts; a composition of peroxydodecanyl and cumene hydroperoxide in a mass ratio of 1: 2: 4 parts of a mixture; sodium polyphosphate: 3.6 parts; azobisisoheptonitrile: 2.6 parts; thioglycolic acid: 3.46 parts.

A method for preparing a solid sheet-shaped polycarboxylate superplasticizer by a soap-free emulsion polymerization method comprises the following operation steps:

1. preparation of soap-free polymers: 20 parts of water, 11 parts of a composition of itaconic acid and maleic acid with the mass ratio of 1:1, 25 parts of 2,2, 2-trifluoroethyl methacrylate, 0.7 part of tert-butyl peroxypivalate and 0.54 part of chained sodium hypophosphite are directly added into a three-neck flask with a stirring device, after uniform stirring, the temperature is controlled to be 65 ℃ for reaction for 2.0 hours, and then the temperature is kept for 2.5 hours, so as to obtain a soap-free polymer for later use;

2. preparation of A, B solution: 858 parts of a composition of allyl polyoxyethylene ether and vinyl butyl ether polyoxyethylene ether in a mass ratio of 1:2, 69 parts of itaconic acid, 3.6 parts of sodium polyphosphate, 18 parts of sodium styrene sulfonate, and 4.1 parts of a composition of sodium methoxide and ethanolamine in a mass ratio of 1:1 are prepared into solution A for later use; preparing 4 parts of a composition of peroxydodecanoyl and cumene hydroperoxide with the mass ratio of 1:2, 2.6 parts of azobisisonitrile, 3.46 parts of thioglycolic acid and 15 parts of water into a solution B for later use;

3. dropwise addition of A, B solution: cooling the soap-free polymer obtained in the step (1) to 50 ℃, slowly dripping the liquid A and the liquid B into a three-neck flask at the same time, wherein the dripping time of the liquid A is 4 hours, the dripping time of the liquid B is 3.5 hours, the dripping time of the liquid B is 0.5 hour shorter than that of the liquid A, stirring while dripping, and keeping the temperature for hours after dripping is finished;

4. preparing a solid sheet type polycarboxylate superplasticizer: and (4) raising the temperature of the solution obtained in the step (3), controlling the temperature to 70 ℃, evaporating the residual water, and removing the redundant initiator to obtain a solid, namely the prepared solid sheet-shaped polycarboxylate superplasticizer.

Example 4

A solid sheet-shaped polycarboxylate superplasticizer prepared by a soap-free emulsion polymerization method is polymerized from the following components in parts by weight, wherein the total mass is 1000 parts, and the components in parts by weight are as follows:

the composition of itaconic acid and maleic acid with the mass ratio of 1: 11 parts of (1); the composition of 2,2, 2-trifluoroethyl methacrylate and perfluorobutylethyl acrylate in a mass ratio of 1: 25 parts of (1); a composition of tert-butyl peroxypivalate and lauroyl peroxide in a mass ratio of 1: 0.7 part; sodium hypophosphite: 0.54 part; itaconic acid: 81 parts; the composition of the allyl polyoxyethylene ether and the vinyl butyl ether polyoxyethylene ether in the mass ratio of 1:2 comprises the following components: 848 parts of a mixture; sodium styrene sulfonate: 17 parts of (1); the mass ratio of the sodium methoxide to the ethanolamine is 1: 4.1 parts; a composition of peroxydodecanyl and cumene hydroperoxide in a mass ratio of 2: 1: 3 parts of a mixture; sodium polyphosphate: 3.6 parts; azobisisoheptonitrile: 2.6 parts; composition of thioglycolic acid and mercaptopropionic acid in a mass ratio of 1: 3.46 parts.

A method for preparing a solid sheet-shaped polycarboxylate superplasticizer by a soap-free emulsion polymerization method comprises the following operation steps:

1. preparation of soap-free polymers: 20 parts of water, 11 parts of a composition of itaconic acid and maleic acid with the mass ratio of 1:1, 25 parts of a composition of 2,2, 2-trifluoroethyl methacrylate and perfluorobutyl ethyl acrylate with the mass ratio of 1:1, 0.7 part of a composition of tert-butyl peroxypivalate and lauroyl peroxide with the mass ratio of 1:1 and 0.54 part of sodium hypophosphite are directly added into a three-neck flask with a stirring device, after uniform stirring, the temperature is controlled to be 60 ℃ for reaction for 2.0 hours, and then the temperature is kept for 3.0 hours, so as to obtain a soap-free polymer for later use;

2. preparation of A, B solution: preparing 848 parts of a composition of allyl polyoxyethylene ether and vinyl butyl ether polyoxyethylene ether in a mass ratio of 1:2, 81 parts of itaconic acid, 3.6 parts of sodium polyphosphate, 3 parts of a composition of lauroyl peroxide and cumene hydroperoxide in a mass ratio of 2:1, 17 parts of sodium styrene sulfonate and 4.1 parts of a composition of sodium methoxide and ethanolamine in a mass ratio of 1:1 into solution A for later use; preparing 2.6 parts of azobisisoheptonitrile, 3.46 parts of a composition of thioglycolic acid and mercaptopropionic acid in a mass ratio of 1:1 and 15 parts of water into a solution B for later use;

3. dropwise addition of A, B solution: cooling the soap-free polymer obtained in the step (1) to 55 ℃, slowly dripping the solution A and the solution B into a three-neck flask at the same time, wherein the dripping time of the solution A is 2.5 hours, the dripping time of the solution B is 4.0 hours, the dripping time of the solution B is 1.5 hours longer than that of the solution A, stirring while dripping, and preserving heat for 1 hour after dripping is finished;

4. preparing a solid sheet type polycarboxylate superplasticizer: and (4) raising the temperature of the solution obtained in the step (3), controlling the temperature to 75 ℃, evaporating the residual water, and removing the redundant initiator to obtain a solid, namely the prepared solid sheet-shaped polycarboxylate superplasticizer.

Example 5

A solid sheet-shaped polycarboxylate superplasticizer prepared by a soap-free emulsion polymerization method is polymerized from the following components in parts by weight, wherein the total mass is 1000 parts, and the components in parts by weight are as follows:

the composition of itaconic acid and maleic acid with the mass ratio of 1: 13 parts; the mass ratio is 2:1 composition of trifluoroethyl acrylate and perfluorooctyl ethyl acrylate: 21 parts of (1); a composition of tert-butyl peroxypivalate and lauroyl peroxide in a mass ratio of 1: 0.7 part, sodium hypophosphite: 0.54 part; fumaric acid: 60 parts; allyl polyoxyethylene ether: 870 parts; sodium styrene sulfonate: 17 parts of (1); the mass ratio of the sodium methoxide to the ethanolamine is 1: 4.1 parts; a composition of peroxydodecanyl and cumene hydroperoxide in a mass ratio of 2: 1: 3 parts of a mixture; sodium polyphosphate: 3.6 parts; azobisisoheptonitrile: 3.6 parts; mercaptopropionic acid: 3.46 parts.

A method for preparing a solid sheet-shaped polycarboxylate superplasticizer by a soap-free emulsion polymerization method comprises the following operation steps:

1. preparation of soap-free polymers: 20 parts of water, 13 parts of a composition of itaconic acid and maleic acid in a mass ratio of 1:1, 21 parts of a composition of itaconic acid and maleic acid in a mass ratio of 2:1, 0.7 part of a composition of trifluoroethyl acrylate and perfluorooctyl ethyl acrylate, 0.54 part of a composition of tert-butyl peroxypivalate and lauroyl peroxide in a mass ratio of 1:1 and 0.54 part of chained sodium hypophosphite are directly added into a three-neck flask with a stirring device, after uniform stirring, the temperature is controlled to react for 1.5 hours at 55 ℃, and then the temperature is kept for 3.0 hours, so that a soap-free polymer is obtained for standby application;

2. preparation of A, B solution: 870 parts of a composition of allyl polyoxyethylene ether and vinyl butyl ether polyoxyethylene ether, 60 parts of fumaric acid, 3.6 parts of sodium polyphosphate, 17 parts of sodium styrene sulfonate and 4.1 parts of a composition of sodium methoxide and ethanolamine in a mass ratio of 1:1 are prepared into solution A for later use; preparing 3 parts of a composition of peroxydodecanoyl and cumene hydroperoxide, 3.6 parts of azobisisonitrile, 3.46 parts of mercaptopropionic acid and 15 parts of water in a mass ratio of 2:1 into a solution B for later use;

3. dropwise addition of A, B solution: cooling the soap-free polymer obtained in the step (1) to 45 ℃, slowly dripping the solution A and the solution B into a three-neck flask at the same time, wherein the dripping time of the solution A is 2.5 hours, the dripping time of the solution B is 4.5 hours, the dripping time of the solution B is 2 hours longer than that of the solution A, stirring while dripping, and preserving heat for 1 hour after dripping is finished;

4. preparing a solid sheet type polycarboxylate superplasticizer: and (4) raising the temperature of the solution obtained in the step (3), controlling the temperature to 70 ℃, evaporating the residual water, and removing the redundant initiator to obtain a solid, namely the prepared solid sheet-shaped polycarboxylate superplasticizer.

Example 6

A solid sheet-shaped polycarboxylate superplasticizer prepared by a soap-free emulsion polymerization method is polymerized from the following components in parts by weight, wherein the total mass is 1000 parts, and the components in parts by weight are as follows:

maleic acid: 7 parts; the mass ratio is 1:2 perfluorooctyl ethyl acrylate and perfluorobutyl ethyl acrylate: 19 parts of a mixture; a composition of tert-butyl peroxypivalate and lauroyl peroxide in a mass ratio of 1: 0.7 part; sodium hypophosphite: 0.54 part; the composition of itaconic acid and fumaric acid with the mass ratio of 1:2 comprises the following components: 60 parts; the composition of the allyl polyoxyethylene ether and the vinyl butyl ether polyoxyethylene ether in the mass ratio of 1:2 comprises the following components: 865 parts of (a); the composition of sodium methallyl sulfonate and sodium styrene sulfonate with the mass ratio of 1:1 comprises the following components: 30 parts of (1); the mass ratio of the sodium methoxide to the ethanolamine is 1: 4.1 parts; a composition of peroxydodecanyl and cumene hydroperoxide in a mass ratio of 2: 1: 3 parts of a mixture; sodium polyphosphate: 3.6 parts; azobisisoheptonitrile: 2.6 parts; the composition of dodecyl mercaptan and mercaptopropionic acid in a mass ratio of 1: 4.46 parts.

A method for preparing a solid sheet-shaped polycarboxylate superplasticizer by a soap-free emulsion polymerization method comprises the following operation steps:

1. preparation of soap-free polymers: 20 parts of water, 7 parts of maleic acid and 19 parts of water in a mass ratio of 1:2, 0.7 part of a composition of tert-butyl peroxypivalate and lauroyl peroxide in a mass ratio of 1:1, and 0.54 part of chain sodium hypophosphite, and directly adding the mixture into a three-neck flask with a stirring device, uniformly stirring, controlling the temperature to react at 70 ℃ for 2.0 hours, and then preserving the temperature for 2.5 hours to obtain a soap-free polymer for later use.

2. Preparation of A, B solution: preparing 865 parts of a composition of allyl polyoxyethylene ether and vinyl butyl ether polyoxyethylene ether in a mass ratio of 1:2, 60 parts of a composition of itaconic acid and fumaric acid in a mass ratio of 1:2, 3.6 parts of sodium polyphosphate, 30 parts of a composition of sodium methallyl sulfonate and sodium styrene sulfonate in a mass ratio of 1:1 and 4.1 parts of a composition of sodium methoxide and ethanolamine in a mass ratio of 1:1 into solution A for later use; and preparing solution B from 2.6 parts of azobisisoheptonitrile, 4.46 parts of a composition of dodecyl mercaptan and mercaptopropionic acid in a mass ratio of 1:1 and 15 parts of water for later use.

3. Dropwise addition of A, B solution: cooling the soap-free polymer obtained in the step (1) to 50 ℃, slowly dripping the solution A and the solution B into a three-neck flask at the same time, wherein the dripping time of the solution A is 2.5 hours, the dripping time of the solution B is 3.8 hours, the dripping time of the solution B is 1.3 hours longer than that of the solution A, stirring while dripping, and preserving heat for 1 hour after dripping is finished;

4. preparing a solid sheet type polycarboxylate superplasticizer: and (4) raising the temperature of the solution obtained in the step (3), controlling the temperature to 65 ℃, evaporating the residual water, and removing the redundant initiator to obtain a solid, namely the prepared solid sheet-shaped polycarboxylate superplasticizer.

Results of example testing

The solid sheet polycarboxylate superplasticizer prepared by the formulation and process of examples 1, 2, 3, 4,5,6 and water were mixed in a ratio of 4: the proportion of 6 is dissolved in water, and the water solubility is determined to be better.

The solid-flake polycarboxylic acid water-reducing agents of examples 1 to 6 described above were tested for initial fluidity of cement paste, fluidity with time, and initial slump/extension and slump/extension with time and compressive strength at the same concentrations as those of the mother solutions of ordinary polycarboxylic acid water-reducing agents, respectively (see tables 1 and 2). The cement used in the experiment is Huaxin 42.5 ordinary silica cement, and the test standard GB/8076-.

TABLE 1

TABLE 2 Effect of different water reducing agents on the flow of Cement paste

According to the initial fluidity of the cement, the time-lapse fluidity, the initial slump/expansion of the concrete, the time-lapse slump/expansion and the compressive strength comparison, the initial fluidity of the cement paste of the solid-sheet polycarboxylate superplasticizer of the embodiments 1-6 is slightly worse than that of the mother liquid of the common superplasticizer, but the slump retention is better; compared with the concrete fluidity data, the initial fluidity and the time-lapse fluidity of the concrete in the examples 1 to 6 are slightly better than those of the common concrete, especially the slump retaining performance; the concrete compressive strength data are compared, and the compressive strengths of the examples 1 to 6 are all higher than the common compressive strength; the overall data shows that the formula and the preparation process of the solid sheet-shaped polycarboxylate superplasticizer are mature and reliable, the conversion rate is high in a high-viscosity reaction environment, the performance of the solid sheet-shaped polycarboxylate superplasticizer is consistent with that of a 40% water reducer mother solution in the current stage, and the slump loss resistance is better.

All of the features disclosed in this specification, or all of the formulations, amounts, and steps of preparation disclosed, may be combined in any combination, except combinations where mutually exclusive features and/or formulations, amounts, and steps are mutually exclusive. Any feature disclosed in this specification (including any accompanying claims and abstract) may be replaced by alternative features serving equivalent or similar purposes, unless expressly stated otherwise. That is, unless expressly stated otherwise, each feature is only an example of a generic series of equivalent or similar features.

The above description is only a non-limiting embodiment of the invention, and many embodiments can be derived, and those skilled in the art can make several modifications and improvements without departing from the inventive concept and without making creative efforts, which all belong to the protection scope of the present invention.