1. A preparation process of a machine-made sand regulator of a carboxylic ester polymer is characterized by sequentially comprising the following operation steps:

the method comprises the following steps: adding 65-85 parts of carboxylic acid monomers, 20-37 parts of ester monomers, 3-6 parts of chain transfer agent, 0.05-0.15 part of polymerization inhibitor, 20-44 parts of 30-35% concentration liquid caustic soda and water into a reaction kettle with a stirrer in parts by mass, and heating to 80-90 ℃ by adopting a water bath;

step two: preparing 150-175 parts of carboxylic acid monomer, 0.05-0.25 part of polymerization inhibitor and water into solution A, preparing 1.93-3.47 parts of initiator, 3-9 parts of chain transfer agent and water into solution B, dripping A, B into a reaction kettle by using a dripping pump, wherein the dripping of the solution A is 1-1.5 hours, and the dripping of the solution B is 1-2 hours; and (3) preserving the heat for 1-2 hours after the A, B liquid is dripped to prepare a machine-made sand regulator solution, and supplementing water to 1000 parts of the total mass to obtain the machine-made sand regulator of the carboxylic ester polymer.

2. The process for preparing the mechanical sand conditioner of carboxylic ester polymer according to claim 1, wherein: the carboxylic acid monomer is any one or more of acrylic acid, maleic acid and itaconic acid.

3. The process for preparing the mechanical sand conditioner of carboxylic ester polymer according to claim 1, wherein: the ester monomer is any one or more of 2-phenoxyethyl methacrylate and 2-propylheptyl methacrylate.

4. The process for preparing the mechanical sand conditioner of carboxylic ester polymer according to claim 1, wherein: the initiator is any one or more of ammonium persulfate, azobisisobutyronitrile, diisopropyl peroxydicarbonate, benzoyl peroxide, di-tert-butyl peroxide and dicyclohexyl peroxydicarbonate.

5. The process for preparing the mechanical sand conditioner of carboxylic ester polymer according to claim 1, wherein: the polymerization inhibitor is one or more of hydroquinone, p-tea quinone, p-benzoquinone, p-tert-butyl catechol, 2, 6-di-tert-butyl-p-methylphenol, 4' -bis-menthyl biphenyl and 1, 1-diphenyl-2-trinitrophenylhydrazine.

6. The process for preparing the mechanical sand conditioner of carboxylic ester polymer according to claim 1, wherein: the chain transfer agent is any one or more of thioglycolic acid, mercaptopropionic acid, mercaptoethanol and mercaptopropanol.

7. The machine-made sand regulator of the carboxylic ester polymer is polymerized by the following components, the total mass of the raw materials is 1000 parts, and the components comprise:

215-260 parts of carboxylic acid monomer;

20-37 parts of an ester monomer;

1.93-3.47 parts of an initiator;

0.1-0.4 part of polymerization inhibitor;

6-15 parts of a chain transfer agent;

20-44 parts of 30-35% concentration liquid caustic soda;

the balance of water.

Background

In the construction engineering industry, sandstone resources are indispensable building materials. However, natural sandstone resources are relatively scarce, and machine-made sand becomes a key research object of engineering construction. In the engineering construction process, the sandstone is used as an important component of a concrete structure material, and the quality of the sandstone has a significant influence on the quality and durability of the whole engineering. The performance of the machine-made sand is influenced by various factors such as particle fineness, gradation, mud content and the like, and in order to ensure the service performance of the machine-made sand, a machine-made sand regulator capable of improving the performance of the machine-made sand is needed. The carboxylic acid monomer and the ester monomer are used as raw materials to synthesize the carboxylic ester polymer, and the molecular weight of the polymer is controlled by adding a polymerization inhibitor and a chain transfer agent and adjusting the initial pH value of the reaction. And the carboxyl small monomer provides a carboxylate radical with negative electricity, so that the carboxyl small monomer is well adsorbed on the surface of the machine-made sand particles with positive electricity, the particle fluidity of the machine-made sand can be effectively adjusted, and the machine-made sand performance is improved.

The patent CN110655346A discloses a machine-made sand regulator and a preparation method thereof, and the embodiment of the invention provides a machine-made sand regulator and a preparation method thereof, wherein the machine-made sand regulator contains a polycarboxylic acid water reducing agent, a glue reducing agent, an early strength agent, an air entraining agent, a polyether type defoaming agent, a compact repairing agent, a viscosity thixotropic agent and water, is suitable for machine-made sand with different grades, can control better working performance of concrete and can ensure the durability requirement of the concrete at the same time, and the machine-made sand regulator provided by the invention can ensure that various detection indexes of newly-mixed concrete are obviously superior to those of common additives in the current market, the slump of the concrete reaches 200mm, the volume weight reaches 2438kg/m3, the activity is good, the 28d strength reaches 66.8MPa, and the strength increment is increased by over 30 percent compared with the common additives.

Patent CN111847967A discloses a machine-made sand regulator for concrete, concrete and a preparation method thereof, the application relates to the technical field of building materials, and discloses a machine-made sand regulator for concrete, which comprises: polycarboxylic acid mother liquor, diethanolisopropanolamine, triisopropanolamine, glycerol and sodium sulfate; the solvent is water. The machine-made sand regulator disclosed by the embodiment of the disclosure has abundant hydroxyl groups, is alkalescent, does not contain chloride ions, is nontoxic and noncorrosive, and is a high-performance green environment-friendly material. The components are simple, and the excellent performance is achieved by regulating and controlling the reasonable proportion of the components. As an additive of concrete, the sand material in the concrete can be all made of machine-made sand. No waste liquid is generated, no cleaning is needed after stirring, no production wastewater is generated, and no waste gas is generated. The application also discloses concrete and a preparation method thereof.

The patent CN110357487A discloses a machine-made sand regulator and application thereof in machine-made sand-containing concrete, and the invention discloses a machine-made sand regulator and application thereof in machine-made sand-containing concrete, wherein the machine-made sand regulator comprises the following raw materials in parts by weight: 10-15% of diethanol monoisopropanolamine, 2-5% of maltodextrin, 5-10% of dipropylamine, 1-3% of air entraining agent for Kelaien polyether concrete, 5-10% of sodium hexametaphosphate and the balance of water, wherein the maltodextrin is prepared by using various starches as raw materials and performing low-degree controlled hydrolysis conversion by an enzymatic process, purification and drying, wherein the hydrolysis DE value of the maltodextrin is below 20%, and the molecular formula of the dipropylamine is C6H15N or (CH3CH2CH2)2 NH; molecular weight 101.19; a colorless liquid with an ammonia odor; can be mixed and dissolved in ethanol, diethyl ether, benzene and acetone; a flammable liquid; the main application is as follows: organic synthesis intermediates, and as solvents. The machine-made sand regulator has the advantages of simple process, convenient operation, no waste in the production process, environmental protection, reliability and contribution to large-scale industrial production, and can effectively improve the strength of concrete, reduce the consumption of rubber materials, regulate the wrapping property of the concrete and increase the fluidity of the concrete when in use.

Different from the patents, the invention aims to prepare the machine-made sand regulator of the carboxylic ester polymer. Unlike the conventional machine-made sand regulator obtained in a complex form, the machine-made sand regulator is prepared in a polymerization mode, the machine-made sand contains a certain amount of clay, the clay surface usually adsorbs positive ions such as potassium, sodium, calcium and the like to form a positive electricity layer, and the carboxylic acid monomer is used as a hydrophilic monomer to provide a good adsorption effect for the machine-made sand regulator, and the ester monomer is introduced, so that carboxylate radicals can be slowly hydrolyzed to release in the later stage of adsorption of the regulator, and the lasting effect of the regulator is improved.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide a mechanism sand regulator of a carboxylic ester polymer. The preparation method has the advantages of simple preparation process, excellent product performance, good stability and wide adaptability.

According to the invention, a carboxylic acid monomer and an ester monomer are used as raw materials to prepare a carboxylic ester polymer through a polymerization reaction, the polymer has good adsorption performance on clay particles, and carboxylic acid groups on molecular side chains can be adsorbed with a positive electricity layer on the clay surface, so that molecular chains of a regulator can be well coated on the clay particle surface to disperse machine-made sand particles and regulate the machine-made sand performance.

The technical scheme of the invention is as follows:

a preparation process of a machine-made sand regulator of a carboxylic ester polymer is characterized by sequentially comprising the following operation steps:

the method comprises the following steps: adding 65-85 parts of carboxylic acid monomers, 20-37 parts of ester monomers, 3-6 parts of chain transfer agent, 0.05-0.15 part of polymerization inhibitor, 20-44 parts of liquid alkali and water into a reaction kettle with a stirrer in parts by mass, and heating to 80-90 ℃ by adopting a water bath;

step two: preparing 150-175 parts of carboxylic acid monomer, 0.05-0.25 part of polymerization inhibitor and water into solution A, preparing 1.93-3.47 parts of initiator, 3-9 parts of chain transfer agent and water into solution B, dripping A, B into a reaction kettle by using a dripping pump, wherein the dripping of the solution A is 1-1.5 hours, and the dripping of the solution B is 1-2 hours; and (3) preserving the heat for 1-2 hours after the A, B liquid is dripped to prepare a machine-made sand regulator solution, and supplementing water to 1000 parts of the total mass to obtain the machine-made sand regulator of the carboxylic ester polymer.

The carboxylic acid monomer is any one or more of acrylic acid, maleic acid and itaconic acid. The preferable mass ratio is 1: 1 of acrylic acid and itaconic acid.

The ester monomer is any one or more of 2-phenoxyethyl methacrylate and 2-propylheptyl methacrylate. The preferable mass ratio is 4: 1 of 2-phenoxyethyl methacrylate and 2-propylheptyl methacrylate.

The initiator is any one or more of ammonium persulfate, azobisisobutyronitrile, diisopropyl peroxydicarbonate, Benzoyl Peroxide (BPO), di-tert-butyl peroxide (DTBP) and dicyclohexyl peroxydicarbonate. The preferable mass ratio is 2: 3 and benzoyl peroxide.

The polymerization inhibitor is hydroquinone, p-tea quinone, p-benzoquinone, p-tert-butyl catechol, 2, 6-di-tert-butyl p-methyl phenol, 4,4' -di-tert-butyl biphenyl and 1, 1-diphenyl-2-trinitrophenylhydrazine, preferably the mass ratio is 1: 1, 2, 6-di-tert-butyl-p-methylphenol and 1, 1-diphenyl-2-trinitrophenylhydrazine.

The chain transfer agent is any one or more of thioglycolic acid, mercaptopropionic acid, mercaptoethanol and mercaptopropanol. Preferably a composition of thioglycolic acid and mercaptopropanol in a mass ratio of 1: 3.

The machine-made sand regulator of the carboxylic ester polymer is polymerized by the following components, the total mass of the raw materials is 1000 parts, and the components comprise:

215-260 parts of carboxylic acid monomer;

20-37 parts of an ester monomer;

1.93-3.47 parts of an initiator;

0.1-0.4 part of polymerization inhibitor;

6-15 parts of a chain transfer agent;

20-44 parts of 30-35% concentration liquid caustic soda;

the balance of water.

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

1. the invention uses carboxylic acid monomer as raw material to synthesize anionic polymer, because the machine-made sand contains a certain amount of clay, the clay surface can usually absorb positive ions such as potassium, sodium, calcium and the like to form a positive electricity layer, thus electrostatic force can be generated between the clay surface and the anionic machine-made sand regulator, the coating capability of the machine-made sand regulator is enhanced, and the action rate of the regulator is improved.

2. According to the invention, a small amount of liquid alkali is added into the bottom material, the addition of the liquid alkali can improve the pH value of a reaction system, reduce the reaction activity of carboxylic acid monomers, delay the initiation rate of an initiator, ensure that the controllability of the whole reaction is better, and facilitate the control of the molecular weight of a polymer, so as to prepare a molecular structure with a short main chain.

3. The invention also selects ester monomers as small synthetic materials, and ester groups can be hydrolyzed in the environment of the machine-made sand to generate carboxylate radicals, so that stronger adsorption performance is provided for regulator molecules which do not adsorb machine-made sand particles at the later stage, the adsorption is facilitated, and the dispersibility of the machine-made sand particles is improved.

Detailed Description

The following examples further describe embodiments of the present invention in detail. The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.

Example 1

A machine-made sand regulator of carboxylic ester polymer is prepared from the following components:

the mass ratio is 1: 235 parts of the acrylic acid and itaconic acid composition of 1;

and (4) mass ratio: 28 parts of a composition of 2-phenoxyethyl methacrylate and 2-propylheptyl methacrylate of 1;

the mass ratio is 2: 2.54 parts of the composition of azobisisobutyronitrile and benzoyl peroxide of 3;

the mass ratio is 1: 0.2 part of a composition of 1, 2, 6-di-tert-butyl-p-methylphenol and 1, 1-diphenyl-2-trinitrophenylhydrazine;

14 parts of a composition of thioglycolic acid and mercaptopropanol in a mass ratio of 1: 3;

38 parts of 30% concentration liquid caustic soda;

the total mass is 1000 parts.

The preparation process of the machine-made sand regulator comprises the following steps:

the method comprises the following steps: adding 75 parts of a mixture of 1: 1, a composition of acrylic acid and itaconic acid, 28 parts by mass ratio 4: 1 of 2-phenoxyethyl methacrylate and 2-propylheptyl methacrylate, 5 parts of a composition of thioglycolic acid and mercaptopropanol in a mass ratio of 1:3, 0.1 part of a composition of 2-phenoxyethyl methacrylate and 2-propylheptyl methacrylate in a mass ratio of 1: 1 of a composition of 2, 6-di-tert-butyl-p-methylphenol and 1, 1-diphenyl-2-trinitrophenylhydrazine, 38 parts of 30% strength liquid caustic soda and water. The mixture was heated to 85 ℃ using a water bath.

Step two: 160 parts of a mixture of 1: 1, 0.1 part of acrylic acid and itaconic acid composition, and the mass ratio of 1: preparing a liquid A from a composition of 1 2, 6-di-tert-butyl-p-methylphenol and 1, 1-diphenyl-2-trinitrophenylhydrazine and water, wherein the mass ratio of the liquid A to the liquid A is 2.54 parts: 3, 9 parts of a composition of azodiisobutyronitrile and benzoyl peroxide, a composition of thioglycolic acid and mercaptopropanol in a mass ratio of 1:3 and water are prepared into a solution B, A, B is dripped into a reaction kettle by a dripping pump, wherein the dripping of the solution A is 1.5 hours, and the dripping of the solution B is 2 hours. And after the A, B liquid is dripped, preserving the heat for 1 hour to prepare the machine-made sand regulator solution. And (5) supplementing water to 1000 parts to obtain the machine-made sand regulator of the carboxylic ester polymer.

Examples 2-6 were prepared in the same manner as in example 1, and the differences in the components and the differences in the process parameters are shown in tables 1 and 2.

Table 1 shows the difference in the components of the production processes of examples 1 to 6

Table 2 shows the difference between the process parameters of the preparation processes of examples 1 to 6

And (3) detecting data:

the embodiment of the invention and the Guangzhou I and building material CS-06 concrete machine-made sand regulator are used for modifying the machine-made sand to prepare a C50 concrete sample, and the following table is obtained through concrete performance detection. (concrete Properties were measured according to the standard of GBT 50080-2002)

Table 3 is a concrete performance table showing the modified machine-made sand of the invention by using 1-6 and CS-06 concrete machine-made sand regulators

According to the detection data in the table 3, it can be seen that the machine-made sand regulator of the present invention can better improve the performance of the machine-made sand, so that the concrete prepared from the machine-made sand regulator has better strength and fluidity.

The above embodiments are merely illustrative of the present invention and are not to be construed as limiting the invention. Although the present invention has been described in detail with reference to the embodiments, it should be understood by those skilled in the art that various combinations, modifications or equivalents may be made to the technical solution of the present invention without departing from the spirit and scope of the technical solution of the present invention, and the technical solution of the present invention is covered by the claims of the present invention.