1. A novel viscosity-reducing slump-retaining functional monomer is characterized by comprising the following raw materials in parts by weight: 60-65 parts of unsaturated acid, 20-30 parts of polyhydric alcohol, 5-10 parts of hydroxyl alcohol, 2-8 parts of polymeric alcohol, 0.5-1 part of esterification catalyst, 5-10 parts of initiator and 2.5 x 10 < -6 > to 5 x 10 < -6 > parts of transition metal catalyst.

2. The novel viscosity-reducing slump-retaining functional monomer of claim 1, wherein: the unsaturated acid is one or more of methacrylic acid, acrylic acid and maleic anhydride.

3. The novel viscosity-reducing slump-retaining functional monomer of claim 1, wherein: the polyalcohol is one or more of ethylene glycol, glycerol, lauryl alcohol or sorbitol.

4. The novel viscosity-reducing slump-retaining functional monomer of claim 1, wherein: the hydroxyl alcohol is one or more of methanol and ethanol.

5. The novel viscosity-reducing slump-retaining functional monomer of claim 1, wherein: the polymeric alcohol is one or more of polyethylene glycol-400, polyethylene glycol-800, polypropylene glycol-400, polypropylene glycol-600 and 1,2, 3-glycerol homopolymer.

6. The novel viscosity-reducing slump-retaining functional monomer of claim 1, wherein: the esterification catalyst is one or more of sulfamic acid, p-toluenesulfonic acid, thionyl chloride, concentrated sulfuric acid and concentrated hydrochloric acid.

7. The novel viscosity-reducing slump-retaining functional monomer of claim 1, wherein: the initiator is one or more of hydrogen peroxide, ammonium persulfate and formaldehyde sodium hydrosulfite.

8. The novel viscosity-reducing slump-retaining functional monomer of claim 1, wherein: the transition metal catalyst is one or more of ferrous sulfate, copper chloride, copper sulfate, nickel oxide and titanium oxide.

9. The novel viscosity-reducing slump-retaining functional monomer as claimed in any one of claims 1 to 8, wherein the preparation method comprises the following steps:

step one, mixing unsaturated acid, polyhydric alcohol, hydroxyl alcohol and polymeric alcohol in parts by weight, starting stirring, heating to 50-60 ℃, adding an esterification catalyst, continuously heating to 105-110 ℃, keeping the temperature constant, reacting for 3.0-4.0h, and keeping the temperature for 2.0h to obtain solution A;

and step two, adding the transition metal catalyst in parts by weight into the liquid A, uniformly stirring, adding an initiator with a certain concentration into the liquid A in a dropwise manner, heating to 115-fold 120 ℃, keeping the temperature constant, keeping the dropwise adding time of the initiator at 2.0-2.5h, continuing to react for 2.0h after the dropwise adding is finished, and stopping heating to 25 ℃ to obtain the novel viscosity-reducing slump-retaining functional monomer.

Background

The polycarboxylate superplasticizer is widely applied to preparing high-performance concrete due to the advantages of high water-reducing rate, good plasticity retention, low yield and environmental protection. At present, due to the exhaustion of river sand resources, machine-made sand is used for preparing concrete as a new generation of important fine aggregate. However, the problem of high concrete viscosity often occurs when high strength grade concrete (strength grade greater than C60) is formulated, which makes the pumping and construction of concrete less desirable. In order to improve the fluidity of concrete mixtures, the mixing amount of the polycarboxylic acid water reducing agent is increased under the premise of keeping the water-cement ratio unchanged. However, when the polycarboxylic acid water reducing agent is sensitive, the cost of concrete preparation is increased under the condition of increasing the mixing amount, and the concrete is often isolated and bled, so that the workability of concrete mixtures is seriously influenced.

At present, the problem of excessive viscosity or increased mixing amount and segregation bleeding of high-grade machine-made sand concrete mixtures is solved in the market by compounding some strong acid substances, sulfates or water-retaining agents in a polycarboxylic acid water reducing agent. However, such acidic substances and inorganic salts often cause the 28d compressive strength of concrete to be damaged, and the plasticity retention performance of the polycarboxylate water reducer is influenced to a certain extent by the water retention agent.

Disclosure of Invention

The invention provides a novel viscosity-reducing slump-retaining functional monomer which has good compatibility with HPEG and TPEG, can effectively reduce the viscosity of the high-strength-grade concrete of machine-made sand, solves the problem of segregation and bleeding caused by high mixing amount of a polycarboxylic acid water reducing agent, and improves the pumping performance of the high-strength-grade concrete of machine-made sand.

In order to achieve the purpose, the invention provides the following technical scheme: a novel viscosity-reducing slump-retaining functional monomer comprises the following raw materials in parts by weight: 60-65 parts of unsaturated acid, 20-30 parts of polyhydric alcohol, 5-10 parts of hydroxyl alcohol, 2-8 parts of polymeric alcohol, 0.5-1 part of esterification catalyst, 5-10 parts of initiator and 2.5 x 10 < -6 > to 5 x 10 < -6 > parts of transition metal catalyst.

Preferably, the unsaturated acid is one or more of methacrylic acid, acrylic acid and maleic anhydride.

Preferably, the polyhydric alcohol is one or more of ethylene glycol, glycerol, lauryl alcohol or sorbitol.

Preferably, the hydroxyl alcohol is one or more of methanol and ethanol.

Preferably, the polymeric alcohol is one or more of polyethylene glycol-400, polyethylene glycol-800, polypropylene glycol-400, polypropylene glycol-600, and 1,2, 3-glycerol homopolymer.

Preferably, the esterification catalyst is one or more of sulfamic acid, p-toluenesulfonic acid, thionyl chloride, concentrated sulfuric acid and concentrated hydrochloric acid.

Preferably, the initiator is one or more of hydrogen peroxide, ammonium persulfate and sodium formaldehyde sulfite.

Preferably, the transition metal catalyst is one or more of ferrous sulfate, copper chloride, copper sulfate, nickel oxide and titanium oxide.

Preferably, the preparation method comprises the following steps:

step one, mixing unsaturated acid, polyhydric alcohol, hydroxyl alcohol and polymeric alcohol in parts by weight, starting stirring, heating to 50-60 ℃, adding an esterification catalyst, continuously heating to 105-110 ℃, keeping the temperature constant, reacting for 3.0-4.0h, and keeping the temperature for 2.0h to obtain solution A;

and step two, adding the transition metal catalyst in parts by weight into the liquid A, uniformly stirring, adding an initiator with a certain concentration into the liquid A in a dropwise manner, heating to 115-fold 120 ℃, keeping the temperature constant, keeping the dropwise adding time of the initiator at 2.0-2.5h, continuing to react for 2.0h after the dropwise adding is finished, and stopping heating to 25 ℃ to obtain the novel viscosity-reducing slump-retaining functional monomer.

The invention has the beneficial effects that: the novel viscosity-reducing slump-retaining functional monomer prepared by reacting unsaturated acid with various types of alcohols has the characteristic of regulating the mother liquor of the polyacid water reducing agent. The polycarboxylic acid water reducer mother liquor synthesized by compounding the novel viscosity-reducing slump-retaining functional monomer with the traditional HPEG or TPEG through free radical copolymerization can reduce the mixing viscosity of the machine-made sand high-strength grade concrete and improve the workability and the pumping performance of the concrete mixture. The problem of concrete segregation and bleeding caused by high mixing amount of the traditional polycarboxylic acid water reducing agent is solved, and the defects of low later strength of hardened concrete caused by compounding of acidic substances and sulfate and rapid loss of concrete mixture caused by a water retaining agent in time are overcome.

Detailed Description

The technical solutions of the present invention are described clearly and completely below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

A novel viscosity-reducing slump-retaining functional monomer comprises the following raw materials in parts by weight: 62 parts of unsaturated acid; 23 parts of polyol; 5 parts of hydroxyl alcohol; 5 parts of polymeric alcohol; 0.8 part of esterification catalyst; 4.2 parts of an initiator; 2.5X 10-6 parts of transition metal catalyst.

The unsaturated acid is maleic anhydride; the polyhydric alcohol is ethylene glycol; the hydroxyl alcohol is methanol; the polymeric alcohol is polyethylene glycol-400; the esterification catalyst is sulfamic acid; the initiator is a mixed solution of 27.0 percent of hydrogen peroxide and 1.8 percent of persulfate; the transition metal catalyst is ferrous sulfate heptahydrate;

the preparation method of the novel viscosity-reducing slump-retaining functional monomer comprises the following steps:

(1) stirring maleic anhydride, ethylene glycol, methanol and polyethylene glycol-400 in parts by weight, heating to 50-60 ℃, adding sulfamic acid, continuously heating to 105-110 ℃, keeping the temperature constant, reacting for 3.0-4.0h, and keeping the temperature for 2.0h to obtain solution A;

(2) adding ferrous sulfate heptahydrate into the solution A in parts by weight, uniformly stirring, adding hydrogen peroxide and ammonium persulfate solution with certain concentration into the solution A in a dropwise manner, heating to the temperature of 115-120 ℃, keeping the temperature constant, keeping the dropwise adding time of a hair-growing agent at 2.0-2.5h, continuing to react for 2.0h after the dropwise adding is finished, and stopping heating to the temperature of 25 ℃ to obtain a viscosity-reducing slump-retaining functional monomer;

the synthesis of the polycarboxylate superplasticizer mother liquor comprises the following raw materials in parts by mass: the bottom material comprises 30 parts of water; 34 parts of TPEG; 0.1 part of ammonium persulfate; 0.35 part of hydrogen peroxide; the A material comprises 5 parts of water; 1 part of acrylic acid; 5 parts of viscosity-reducing slump-retaining functional monomer; the material B comprises 8.335 parts of water; 0.075 part of ascorbic acid; 0.14 part of mercaptopropionic acid;

the synthesis steps of the polycarboxylate superplasticizer mother liquor are as follows:

adding bottom water into a reaction kettle, adding TPEG, stirring at normal temperature until the TPEG is completely dissolved, adding ammonium persulfate and hydrogen peroxide, and stirring uniformly.

And adding the prepared material A and the prepared material B into a reaction kettle in a dropwise manner, wherein the dropwise adding time of the material A is 90min, and the dropwise adding time of the material B is 120 min.

And (3) after finishing the dropwise addition, supplementing 16 parts of water into the reaction kettle, then preserving the heat for 2.0h, and discharging to obtain a polycarboxylic acid water reducing agent mother liquor.

Example 2

A novel viscosity-reducing slump-retaining functional monomer comprises the following raw materials in parts by weight: 65 parts of unsaturated acid; 20 parts of polyol; 2 parts of hydroxyl alcohol; 8 parts of polymeric alcohol; 0.5 part of esterification catalyst; 4.5 parts of an initiator; 3.0X 10-6 portions of transition metal catalyst.

The unsaturated acid is maleic anhydride and methacrylic acid which are respectively 50 parts and 15 parts; the polyalcohol is glycerol; the hydroxyl alcohol is ethanol; the polymeric alcohol is polypropylene glycol-800; the esterification catalyst is p-toluenesulfonic acid; the initiator is 27.0 percent of hydrogen peroxide; the transition metal catalyst is a mixture of ferrous sulfate heptahydrate and copper chloride, and the mass ratio is 2: 1;

the preparation method of the novel viscosity-reducing slump-retaining functional monomer comprises the following steps:

(1) stirring maleic anhydride, methacrylic acid, glycerol, ethanol and polypropylene glycol-600 in parts by weight, heating to 50-60 ℃, adding p-toluenesulfonic acid, continuously heating to 105-110 ℃, keeping the temperature constant, reacting for 3.0-4.0h, and keeping the temperature for 2.0h to obtain solution A;

(2) adding a mixture of ferrous sulfate heptahydrate and copper chloride in parts by weight into the solution A, uniformly stirring, adding hydrogen peroxide with a certain concentration into the solution A in a dropwise manner, heating to 115-120 ℃, keeping the temperature constant, keeping the dropwise adding time of a hair-growing agent at 2.0-2.5h, continuing to react for 2.0h after the dropwise adding is finished, and stopping heating to 25 ℃ to obtain a viscosity-reducing slump-retaining functional monomer;

the synthesis of the polycarboxylate superplasticizer mother liquor comprises the following raw materials in parts by mass: the bottom material comprises 30 parts of water; 34 parts of TPEG; 0.1 part of ammonium persulfate; 0.35 part of hydrogen peroxide; the A material comprises 5 parts of water; 0.6 part of acrylic acid; 5 parts of viscosity-reducing slump-retaining functional monomer; the material B comprises 8.735 parts of water; 0.075 part of ascorbic acid; 0.14 part of mercaptopropionic acid;

the synthesis method of the polycarboxylate superplasticizer mother liquor is the same as that of example 1.

Example 3

A novel viscosity-reducing slump-retaining functional monomer comprises the following raw materials in parts by weight: 68 parts of unsaturated acid; 22 parts of polyol; 2 parts of hydroxyl alcohol; 2 parts of polymeric alcohol; 1 part of an esterification catalyst; 5 parts of an initiator; 4.0X 10-6 parts of transition metal catalyst.

The unsaturated acid is maleic anhydride; the polyhydric alcohol is ethylene glycol; the hydroxyl alcohol is methanol; the polymeric alcohol is polyethylene glycol-800; the esterification catalyst is p-toluenesulfonic acid; the initiator is 27.0 percent of hydrogen peroxide; the transition metal catalyst is a mixture of ferrous sulfate heptahydrate and copper chloride, and the mass ratio is 2: 1;

the preparation method of the novel viscosity-reducing slump-retaining functional monomer comprises the following steps:

(1) stirring maleic anhydride, ethylene glycol, methanol and polyethylene glycol-800 in parts by weight, heating to 50-60 ℃, adding p-toluenesulfonic acid, continuously heating to 105-110 ℃, keeping the temperature constant, reacting for 3.0-4.0h, and keeping the temperature for 2.0h to obtain solution A;

(2) adding a mixture of ferrous sulfate heptahydrate and copper chloride in parts by weight into the solution A, uniformly stirring, adding hydrogen peroxide with a certain concentration into the solution A in a dropwise manner, heating to 115-120 ℃, keeping the temperature constant, keeping the dropwise adding time of a hair-growing agent at 2.0-2.5h, continuing to react for 2.0h after the dropwise adding is finished, and stopping heating to 25 ℃ to obtain a viscosity-reducing slump-retaining functional monomer;

the synthesis of the polycarboxylate superplasticizer mother liquor comprises the following raw materials in parts by mass: the bottom material comprises 30 parts of water; 34 parts of TPEG; 0.1 part of ammonium persulfate; 0.35 part of hydrogen peroxide; the A material comprises 5 parts of water; 1 part of acrylic acid; 5 parts of viscosity-reducing slump-retaining functional monomer; the material B comprises 8.335 parts of water; 0.075 part of ascorbic acid; 0.14 part of mercaptopropionic acid;

the procedure for the synthesis of the mother liquor of the polycarboxylic acid water reducing agent is as in example 1.

Example 4

A novel viscosity-reducing slump-retaining functional monomer comprises the following raw materials in parts by weight: 70 parts of unsaturated acid; 17 parts of polyol; 2 parts of hydroxyl alcohol; 6 parts of polymeric alcohol; 0.6 part of esterification catalyst; 4.4 parts of an initiator; 4.0X 10-6 parts of transition metal catalyst.

The unsaturated acid is maleic anhydride and acrylic acid which are respectively 55 parts and 15 parts; the polyhydric alcohol is ethylene glycol; the hydroxyl alcohol is ethanol; 1,2, 3-glycerol homopolymer; the esterification catalyst is concentrated sulfuric acid; the initiator is a mixed solution of 27.0 percent of hydrogen peroxide and 2.0 percent of formaldehyde sodium sulfite; the transition metal catalyst is a mixture of nickel oxide and titanium oxide;

the preparation method of the novel viscosity-reducing slump-retaining functional monomer comprises the following steps:

(1) stirring maleic anhydride, acrylic acid, ethylene glycol, ethanol and 1,2, 3-glycerol homopolymer in parts by weight, heating to 50-60 ℃, adding concentrated sulfuric acid, continuously heating to 105-110 ℃, keeping the temperature constant, reacting for 3.0-4.0h, and keeping the temperature for 2.0h to obtain solution A;

(2) adding a mixture of nickel oxide and titanium oxide in parts by weight into the solution A, uniformly stirring, adding a mixed solution of hydrogen peroxide and formaldehyde sodium sulfite with a certain concentration into the solution A in a dropwise manner, heating to 115 ℃ and 120 ℃, keeping the temperature constant, keeping the dropwise adding time of a hair-inducing agent at 2.0-2.5h, continuing to react for 2.0h after the dropwise adding is finished, and stopping heating to 25 ℃ to obtain a viscosity-reducing slump-retaining functional monomer;

the synthesis of the polycarboxylate superplasticizer mother liquor comprises the following raw materials in parts by mass: the bottom material comprises 30 parts of water; 34 parts of TPEG; 0.1 part of ammonium persulfate; 0.35 part of hydrogen peroxide; the A material comprises 5 parts of water; 0.7 part of acrylic acid; 5 parts of viscosity-reducing slump-retaining functional monomer; the material B comprises 8.635 parts of water; 0.075 part of ascorbic acid; 0.14 part of mercaptopropionic acid;

the procedure for the synthesis of the mother liquor of the polycarboxylic acid water reducing agent is as in example 1.

Table 1: mixing proportion of machine-made sand C60 concrete

Table 2: performance testing of machine-made sand C60 concrete mixture

Comparative examples 1 and 3 are commercially available common polycarboxylate superplasticizers, comparative example 2 is a polycarboxylate superplasticizer compounded with inorganic salts and acidic substances, and comparative example 4 is a polycarboxylate superplasticizer compounded with a water-retaining agent.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.