阅读说明：本技术 一种粉态减水剂及其制备方法 (Powdery water reducing agent and preparation method thereof ) 是由 刘少林 刘俊杰 田帅 廖文文 凌志 邓凯 于 2020-08-11 设计创作，主要内容包括：本发明公开了一种粉态减水剂及其制备方法,涉及减水剂技术领域,所述减水剂按重量份包括以下组分：改性聚氧乙烯醚30～50份、丙烯酸20～30份、马来酸二乙酯8～16份、巯基乙酸5～10份、浓硫酸1～3份、硫酸钠1～2份、碱性调节剂0.3～2份、改性木质素1～3份、防粘助剂0.5～1.5份、发泡剂0.1～0.3份、消泡剂0.05～0.15份和去离子水70～90份。本发明粉状减水剂具有低掺量、高减水率、低含气量、低坍落度、不易结块、和易性好、可快速溶解且稳定性好的优点,能够有效提高混凝土的强度及性能,且本发明制备工艺简单,操作方便,成本较低,节能环保,适合工业化生产。(The invention discloses a powdery water reducer and a preparation method thereof, and relates to the technical field of water reducers, wherein the water reducer comprises the following components in parts by weight: 30-50 parts of modified polyoxyethylene ether, 20-30 parts of acrylic acid, 8-16 parts of diethyl maleate, 5-10 parts of mercaptoacetic acid, 1-3 parts of concentrated sulfuric acid, 1-2 parts of sodium sulfate, 0.3-2 parts of an alkaline regulator, 1-3 parts of modified lignin, 0.5-1.5 parts of an anti-sticking auxiliary agent, 0.1-0.3 part of a foaming agent, 0.05-0.15 part of a defoaming agent and 70-90 parts of deionized water. The powdery water reducing agent disclosed by the invention has the advantages of low mixing amount, high water reducing rate, low gas content, low slump, difficulty in caking, good workability, quick dissolution and good stability, can effectively improve the strength and performance of concrete, and is simple in preparation process, convenient to operate, low in cost, energy-saving, environment-friendly and suitable for industrial production.)

1. A powdery water reducing agent is characterized in that: the water reducing agent comprises the following components in parts by weight: 30-50 parts of modified polyoxyethylene ether, 20-30 parts of acrylic acid, 8-16 parts of diethyl maleate, 5-10 parts of mercaptoacetic acid, 1-3 parts of concentrated sulfuric acid, 1-2 parts of sodium sulfate, 0.3-2 parts of an alkaline regulator, 1-3 parts of modified lignin, 0.5-1.5 parts of an anti-sticking auxiliary agent, 0.1-0.3 part of a foaming agent, 0.05-0.15 part of a defoaming agent and 70-90 parts of deionized water.

2. The powdery water reducer of claim 1, which is characterized in that: the modified polyoxyethylene ether is prepared by the following method:

s11: adding glucose and fatty alcohol-polyoxyethylene ether into a reaction container according to the mass ratio of 1: 3-5, adding an acid catalyst accounting for 0.1-0.3% of the total mass, carrying out glycosylation reaction for 2-5 h, adjusting the pH value of the neutralization solution to 6-7, and filtering;

s12: adding chloroacetic acid into the glycosidated fatty alcohol-polyoxyethylene ether, heating to 80-100 ℃, and reacting for 20-40 min;

s13: and then adding a sodium hydroxide aqueous solution for dehydration treatment for 0.5-1 h, keeping the temperature at 120-130 ℃, and reacting and cooling to obtain the modified polyoxyethylene ether.

3. The powdery water reducer of claim 1, which is characterized in that: the alkaline regulator is any one or mixture of zinc oxide, sodium hydroxide, calcium hydroxide, sodium carbonate and potassium hydroxide.

4. The powdery water reducer of claim 1, which is characterized in that: the anti-sticking auxiliary agent is any one of diatomite, zeolite powder or calcium bicarbonate.

5. The powdery water reducer of claim 1, which is characterized in that: the foaming agent is any one of sodium bicarbonate or magnesium carbonate.

6. The powdery water reducer of claim 1, which is characterized in that: the defoaming agent is any one of polyether defoaming agent or polyether modified organic silicon defoaming agent.

7. The preparation method of the powdery water reducer according to any one of claims 1 to 6, characterized by comprising the following steps: the concrete preparation method of the water reducing agent comprises the following steps:

s100: preparing raw materials: preparing required raw materials of modified polyoxyethylene ether, acrylic acid, diethyl maleate, thioglycollic acid, concentrated sulfuric acid, sodium sulfate, an alkaline regulator, modified lignin, an anti-sticking auxiliary agent, a foaming agent, a defoaming agent and deionized water according to the weight parts for later use;

s101: mixing and reacting: sequentially adding modified polyoxyethylene ether, acrylic acid, diethyl maleate and thioglycolic acid into a reaction kettle, adding deionized water while stirring, adding deionized water for three times, uniformly mixing, heating to 90-120 ℃, and reacting for 1-3 hours to obtain a mixed solution;

s102: base material preparation: keeping the temperature of the reaction kettle unchanged, adding concentrated sulfuric acid and sodium sulfate into the mixed solution, uniformly stirring for reacting for 0.5-1 h, then sequentially adding modified lignin, an anti-sticking auxiliary agent and a foaming agent for stirring, mixing uniformly, cooling to 70-80 ℃, and reacting for 3-5 h to obtain a water reducer base material;

s103: defoaming: adding a defoaming agent into the base material, uniformly mixing, stirring and reacting for 6-12 h, and cooling to normal temperature;

s104: neutralizing: adding an alkaline regulator into the cooled base material, and regulating the pH value to 6.5-7.5;

s105: spray drying: and (3) concentrating the neutralized base material under reduced pressure, and performing spray drying treatment to obtain a finished product of the powdery water reducing agent.

Technical Field

The invention relates to the technical field of water reducing agents, in particular to a powdery water reducing agent and a preparation method thereof.

Background

The water reducing agent is a concrete admixture capable of reducing the water consumption for mixing under the condition of maintaining the slump constant of concrete basically. Most of them are anionic surfactants, such as lignosulfonate and naphthalene sulfonate formaldehyde polymer. After the concrete mixture is added, the dispersion effect on cement particles is achieved, the workability of the concrete mixture can be improved, the unit water consumption is reduced, and the fluidity of the concrete mixture is improved; or the unit cement consumption is reduced, and the cement is saved. Is divided into aqueous solution and powder according to appearance.

However, the powder water reducing agent in the current market is easy to cause caking phenomenon in the actual use process, the water solubility is poor, the existing water reducing agent is usually high in mixing amount and high in cost in order to achieve high water reducing rate, and meanwhile, the existing water reducing agent is high in air content and slump and cannot meet the use requirements of the current market. Therefore, the technical personnel in the field provide a powdery water reducing agent and a preparation method thereof to solve the problems in the background technology.

Disclosure of Invention

The invention aims to provide a powdery water reducing agent and a preparation method thereof, the powdery water reducing agent prepared by using modified polyoxyethylene ether as a main raw material has the advantages of low doping amount, high water reducing rate, low gas content, low slump, difficult caking, good workability, quick dissolution and good stability, can effectively improve the strength and performance of concrete, and solves the problems in the background technology.

In order to achieve the purpose, the invention provides the following technical scheme: a powdery water reducing agent comprises the following components in parts by weight: 30-50 parts of modified polyoxyethylene ether, 20-30 parts of acrylic acid, 8-16 parts of diethyl maleate, 5-10 parts of mercaptoacetic acid, 1-3 parts of concentrated sulfuric acid, 1-2 parts of sodium sulfate, 0.3-2 parts of an alkaline regulator, 1-3 parts of modified lignin, 0.5-1.5 parts of an anti-sticking auxiliary agent, 0.1-0.3 part of a foaming agent, 0.05-0.15 part of a defoaming agent and 70-90 parts of deionized water.

As a further scheme of the invention: the modified polyoxyethylene ether is prepared by the following method:

s11: adding glucose and fatty alcohol-polyoxyethylene ether into a reaction container according to the mass ratio of 1: 3-5, adding an acid catalyst accounting for 0.1-0.3% of the total mass, carrying out glycosylation reaction for 2-5 h, adjusting the pH value of the neutralization solution to 6-7, and filtering;

s12: adding chloroacetic acid into the glycosidated fatty alcohol-polyoxyethylene ether, heating to 80-100 ℃, and reacting for 20-40 min;

s13: and then adding a sodium hydroxide aqueous solution for dehydration treatment for 0.5-1 h, keeping the temperature at 120-130 ℃, and reacting and cooling to obtain the modified polyoxyethylene ether.

As a still further scheme of the invention: the alkaline regulator is any one or mixture of zinc oxide, sodium hydroxide, calcium hydroxide, sodium carbonate and potassium hydroxide.

As a still further scheme of the invention: the anti-sticking auxiliary agent is any one of diatomite, zeolite powder or calcium bicarbonate.

As a still further scheme of the invention: the foaming agent is any one of sodium bicarbonate or magnesium carbonate.

As a still further scheme of the invention: the defoaming agent is any one of polyether defoaming agent or polyether modified organic silicon defoaming agent.

A preparation method of a powdery water reducer comprises the following steps:

s100: preparing raw materials: preparing required raw materials of modified polyoxyethylene ether, acrylic acid, diethyl maleate, thioglycollic acid, concentrated sulfuric acid, sodium sulfate, an alkaline regulator, modified lignin, an anti-sticking auxiliary agent, a foaming agent, a defoaming agent and deionized water according to the weight parts for later use;

s101: mixing and reacting: sequentially adding modified polyoxyethylene ether, acrylic acid, diethyl maleate and thioglycolic acid into a reaction kettle, adding deionized water while stirring, adding deionized water for three times, uniformly mixing, heating to 90-120 ℃, and reacting for 1-3 hours to obtain a mixed solution;

s102: base material preparation: keeping the temperature of the reaction kettle unchanged, adding concentrated sulfuric acid and sodium sulfate into the mixed solution, uniformly stirring for reacting for 0.5-1 h, then sequentially adding modified lignin, an anti-sticking auxiliary agent and a foaming agent for stirring, mixing uniformly, cooling to 70-80 ℃, and reacting for 3-5 h to obtain a water reducer base material;

s103: defoaming: adding a defoaming agent into the base material, uniformly mixing, stirring and reacting for 6-12 h, and cooling to normal temperature;

s104: neutralizing: adding an alkaline regulator into the cooled base material, and regulating the pH value to 6.5-7.5;

s105: spray drying: and (3) concentrating the neutralized base material under reduced pressure, and performing spray drying treatment to obtain a finished product of the powdery water reducing agent.

Compared with the prior art, the invention has the beneficial effects that: the invention discloses a powdery water reducing agent and a preparation method thereof, the powdery water reducing agent is prepared by taking modified polyoxyethylene ether as a main raw material, so that the water reducing agent has good water solubility and mildness, has the advantages of low mixing amount, high water reducing rate, low air content, low slump, difficult caking, good workability, quick dissolution and good stability, can effectively improve the strength and the performance of concrete, and is simple in preparation process, convenient to operate, low in cost, energy-saving, environment-friendly and suitable for industrial production.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and 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.

In the embodiment of the present invention, the first and second substrates,