阅读说明：本技术 一种混凝土砂浆抗裂外加剂及其制备方法 (Concrete mortar anti-cracking additive and preparation method thereof ) 是由 刘少林 刘俊杰 田帅 廖文文 凌志 邓凯 于 2020-08-18 设计创作，主要内容包括：本发明公开了一种混凝土砂浆抗裂外加剂及其制备方法,涉及外加剂技术领域,所述外加剂按重量份包括以下组分：酯型聚羧酸减水剂40～50份、改性叶腊石粉15～25份、掺合料10～20份、硬脂酸钠8～12份、二乙醇胺5～9份、甲基纤维素1～3份、表面活性剂0.3～0.5份、膨胀剂0.1～0.5份、防冻剂0.1～0.3份、引气剂0.1～0.3份和去离子水25～45份。本发明能够有效改善混凝土砂浆的韧性及强度,同时,具有抗冻、补偿收缩,减少泌水率的作用；本发明产品集防水、抗渗、抗裂、抗压于一体,能够解决混凝土砂浆易开裂、收缩的问题,提高了混凝土的耐久性,且本发明制备工艺简单,操作便利,生产成本较低,生产周期较短,适宜大规模生产。(The invention discloses a concrete mortar anti-cracking additive and a preparation method thereof, relating to the technical field of additives, wherein the additive comprises the following components in parts by weight: 40-50 parts of ester type polycarboxylic acid water reducing agent, 15-25 parts of modified pyrophyllite powder, 10-20 parts of admixture, 8-12 parts of sodium stearate, 5-9 parts of diethanolamine, 1-3 parts of methyl cellulose, 0.3-0.5 part of surfactant, 0.1-0.5 part of expanding agent, 0.1-0.3 part of antifreezing agent, 0.1-0.3 part of air entraining agent and 25-45 parts of deionized water. The invention can effectively improve the toughness and strength of the concrete mortar, and simultaneously has the effects of freezing resistance, shrinkage compensation and bleeding rate reduction; the product of the invention integrates water resistance, impermeability, crack resistance and pressure resistance, can solve the problems of easy cracking and shrinkage of concrete mortar, and improves the durability of concrete.)

1. The concrete mortar anti-cracking additive is characterized in that: the additive comprises the following components in parts by weight: 40-50 parts of ester type polycarboxylic acid water reducing agent, 15-25 parts of modified pyrophyllite powder, 10-20 parts of admixture, 8-12 parts of sodium stearate, 5-9 parts of diethanolamine, 1-3 parts of methyl cellulose, 0.3-0.5 part of surfactant, 0.1-0.5 part of expanding agent, 0.1-0.3 part of antifreezing agent, 0.1-0.3 part of air entraining agent and 25-45 parts of deionized water.

2. The concrete mortar crack resistance additive according to claim 1, which is characterized in that: the additive comprises the following components in parts by weight: 45 parts of ester type polycarboxylic acid water reducing agent, 20 parts of modified pyrophyllite powder, 15 parts of admixture, 10 parts of sodium stearate, 7 parts of diethanolamine, 2 parts of methyl cellulose, 0.4 part of surfactant, 0.3 part of expanding agent, 0.2 part of antifreezing agent, 0.2 part of air entraining agent and 35 parts of deionized water.

3. The concrete mortar crack resistance additive according to claim 1, which is characterized in that: the modified pyrophyllite powder is prepared by the following method:

s11: mixing pyrophyllite powder and absolute ethyl alcohol according to the proportion of 1: 5-8, and performing ball milling and mixing for 0.5-1 h to obtain a mixture;

s12, adding calcium chloride and aluminum chloride into the mixture, and performing ball milling and mixing for 0.2-0.5 h;

and S13, sequentially adding a titanate coupling agent and a polymethylsilane coupling agent, and performing ball milling and mixing for 0.5-1 h to obtain the modified pyrophyllite powder.

4. The concrete mortar crack resistance additive according to claim 3, which is characterized in that: in the step S12, the addition amount of calcium chloride and aluminum chloride is 3-7% of the weight of the pyrophyllite powder.

5. The concrete mortar crack resistance additive according to claim 3, which is characterized in that: in the step S13, the addition amount of the titanate coupling agent and the polymethylsilane coupling agent is 1-3% of the weight of the pyrophyllite powder.

6. The concrete mortar crack resistance additive according to claim 1, which is characterized in that: the admixture is a mixture of fly ash, slag, superfine silicon powder, zeolite powder, steel slag powder, phosphorous slag powder and limestone powder.

7. The concrete mortar crack resistance additive according to claim 1, which is characterized in that: the surfactant is any one or a mixture of more of calcium lignosulphonate, sodium abietate, rosin, dodecylbenzene sulfonic acid and sodium dodecylbenzene sulfate.

8. The concrete mortar crack resistance additive according to claim 1, which is characterized in that: the air entraining agent is any one of lignosulfonate, fatty acid or resin acid.

9. The method for preparing the concrete mortar anti-cracking admixture according to any one of claims 1 to 8, which is characterized by comprising the following steps: the concrete preparation method of the additive comprises the following steps:

preparing S21 raw material: weighing the required raw materials of ester type polycarboxylate superplasticizer, modified pyrophyllite powder, admixture, sodium stearate, diethanolamine, methyl cellulose, surfactant, expanding agent, antifreezing agent, air entraining agent and deionized water according to the weight part ratio for later use;

preparing an S22 mixed solution: adding an ester type polycarboxylic acid water reducing agent into deionized water, uniformly stirring, sequentially adding modified pyrophyllite powder, an admixture, sodium stearate, diethanolamine and methylcellulose, stirring while adding, uniformly mixing, and emulsifying and homogenizing to obtain a mixed solution;

s23 addition of additives: and sequentially adding an air entraining agent, a surfactant, an expanding agent and an antifreezing agent into the mixed solution, uniformly stirring, and reacting for 1-3 hours to obtain the waterproof agent product.

Technical Field

The invention relates to the technical field of additives, in particular to a concrete mortar anti-cracking additive and a preparation method thereof.

Background

The concrete admixture is a chemical substance which is added in the process of stirring the concrete, accounts for less than 5 percent of the mass of the cement and can obviously improve the performance of the concrete. The concrete admixture has the characteristics of multiple varieties, small mixing amount, great influence on the performance of concrete, low investment, quick response and obvious technical and economic benefits.

The concrete mortar admixture is mainly a naphthalene-based high-efficiency water reducing agent, a polycarboxylic acid high-performance water reducing agent and an aliphatic high-efficiency water reducing agent.

However, the concrete mortar anti-cracking admixture in the current market has single function, the concrete mortar is easy to crack, shrink and the like in the using process, the crack resistance and the compressive strength are poor, the durability is not ideal, the existing admixture is more in preparation raw materials, more complex in preparation method, higher in production cost and longer in production period, and the requirements of the current market cannot be met. Accordingly, one skilled in the art has provided a concrete mortar anti-crack admixture and a method for preparing the same to solve the problems set forth in the background art.

Disclosure of Invention

The invention aims to provide a concrete mortar anti-cracking additive and a preparation method thereof, and the additive can effectively improve the toughness and strength of the concrete mortar, ensure the compactness of the concrete mortar and improve the anti-cracking and anti-compression performance of the concrete mortar through the synergistic effect and reasonable proportioning of different raw materials.

In order to achieve the purpose, the invention provides the following technical scheme: the concrete mortar anti-cracking additive comprises the following components in parts by weight: 40-50 parts of ester type polycarboxylic acid water reducing agent, 15-25 parts of modified pyrophyllite powder, 10-20 parts of admixture, 8-12 parts of sodium stearate, 5-9 parts of diethanolamine, 1-3 parts of methyl cellulose, 0.3-0.5 part of surfactant, 0.1-0.5 part of expanding agent, 0.1-0.3 part of antifreezing agent, 0.1-0.3 part of air entraining agent and 25-45 parts of deionized water.

As a further scheme of the invention: the additive comprises the following components in parts by weight: 45 parts of ester type polycarboxylic acid water reducing agent, 20 parts of modified pyrophyllite powder, 15 parts of admixture, 10 parts of sodium stearate, 7 parts of diethanolamine, 2 parts of methyl cellulose, 0.4 part of surfactant, 0.3 part of expanding agent, 0.2 part of antifreezing agent, 0.2 part of air entraining agent and 35 parts of deionized water.

As a still further scheme of the invention: the modified pyrophyllite powder is prepared by the following method:

s11: mixing pyrophyllite powder and absolute ethyl alcohol according to the proportion of 1: 5-8, and performing ball milling and mixing for 0.5-1 h to obtain a mixture;

s12, adding calcium chloride and aluminum chloride into the mixture, and performing ball milling and mixing for 0.2-0.5 h;

and S13, sequentially adding a titanate coupling agent and a polymethylsilane coupling agent, and performing ball milling and mixing for 0.5-1 h to obtain the modified pyrophyllite powder.

As a still further scheme of the invention: in the step S12, the addition amount of calcium chloride and aluminum chloride is 3-7% of the weight of the pyrophyllite powder.

As a still further scheme of the invention: in the step S13, the addition amount of the titanate coupling agent and the polymethylsilane coupling agent is 1-3% of the weight of the pyrophyllite powder.

As a still further scheme of the invention: the admixture is a mixture of fly ash, slag, superfine silicon powder, zeolite powder, steel slag powder, phosphorous slag powder and limestone powder.

As a still further scheme of the invention: the surfactant is any one or a mixture of more of calcium lignosulphonate, sodium abietate, rosin, dodecylbenzene sulfonic acid and sodium dodecylbenzene sulfate.

As a still further scheme of the invention: the air entraining agent is any one of lignosulfonate, fatty acid or resin acid.

A preparation method of a concrete mortar anti-cracking additive comprises the following steps:

preparing S21 raw material: weighing the required raw materials of ester type polycarboxylate superplasticizer, modified pyrophyllite powder, admixture, sodium stearate, diethanolamine, methyl cellulose, surfactant, expanding agent, antifreezing agent, air entraining agent and deionized water according to the weight part ratio for later use;

preparing an S22 mixed solution: adding an ester type polycarboxylic acid water reducing agent into deionized water, uniformly stirring, sequentially adding modified pyrophyllite powder, an admixture, sodium stearate, diethanolamine and methylcellulose, stirring while adding, uniformly mixing, and emulsifying and homogenizing to obtain a mixed solution;

s23 addition of additives: and sequentially adding an air entraining agent, a surfactant, an expanding agent and an antifreezing agent into the mixed solution, uniformly stirring, and reacting for 1-3 hours to obtain the waterproof agent product.

Compared with the prior art, the invention has the beneficial effects that: the invention discloses a concrete mortar anti-cracking additive and a preparation method thereof, wherein the raw materials are added with ester polycarboxylic acid water reducing agent, modified pyrophyllite powder, admixture and other components, and through the synergistic effect and reasonable proportioning of different raw materials, the toughness and strength of the concrete mortar can be effectively improved, the compactness of the concrete mortar is ensured, the concrete mortar is prevented from leaking and cracking, the anti-cracking and anti-compression performance of the concrete mortar is improved, and meanwhile, the concrete mortar anti-cracking additive has the effects of freezing resistance, shrinkage compensation and bleeding rate reduction.

The product of the invention integrates water resistance, impermeability, crack resistance and pressure resistance, can solve the problems of easy cracking and shrinkage of concrete mortar, and improves the durability of concrete.

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,