阅读说明：本技术 一种防龟裂空鼓的干混砂浆添加剂及含有该添加剂的干混砂浆 (Anti-cracking empty-bulging dry-mixed mortar additive and dry-mixed mortar containing same ) 是由 朱佳媚 程业秀 于 2019-12-01 设计创作，主要内容包括：本发明公开了一种防龟裂空鼓的干混砂浆添加剂,其特征在于,包括按重量份计的如下组分：两性离子液体改性脱氢松香胺5-10份、聚乙二醇二丙烯酸酯/三乙氧硅基丙基马来酸/N,N’-亚甲基双丙烯酰胺共聚物2-5份、腐殖酸1-3份、浮石粉10-20份、皓砂8-12份、贝壳粉3-8份、坡缕石粉10-20份、珍珠石粉5-10份、植物多糖2-5份、甘磷酸胆碱0.5-1.5份。本发明还公开了所述干混砂浆添加剂的制备方法。本发明公开的干混砂浆添加剂性能稳定性好,掺量小,能有效改善砂浆的保水率和黏聚性,提高砂浆的强度及与基层的黏结性、协同变形性能；还能有效防止墙面龟裂、空鼓,具有较高的经济价值、社会价值和推广应用价值。(The invention discloses an anti-cracking empty-bulging dry-mixed mortar additive which is characterized by comprising the following components in parts by weight: 5-10 parts of zwitterionic liquid modified dehydroabietylamine, 2-5 parts of polyethylene glycol diacrylate/triethoxysilylpropyl maleic acid/N, N' -methylene bisacrylamide copolymer, 1-3 parts of humic acid, 10-20 parts of pumice powder, 8-12 parts of haydite, 3-8 parts of shell powder, 10-20 parts of palygorskite powder, 5-10 parts of pearl stone powder, 2-5 parts of plant polysaccharide and 0.5-1.5 parts of choline alfoscerate. The invention also discloses a preparation method of the dry-mixed mortar additive. The dry-mixed mortar additive disclosed by the invention has good performance stability and small mixing amount, can effectively improve the water retention rate and cohesiveness of mortar, and improves the strength of mortar, cohesiveness with a base layer and cooperative deformation performance; the wall surface can be effectively prevented from cracking and hollowing, and the method has higher economic value, social value and popularization and application value.)

1. The anti-cracking and anti-hollowing dry-mixed mortar additive is characterized by comprising the following components in parts by weight: 5-10 parts of zwitterionic liquid modified dehydroabietylamine, 2-5 parts of polyethylene glycol diacrylate/triethoxysilylpropyl maleic acid/N, N' -methylene bisacrylamide copolymer, 1-3 parts of humic acid, 10-20 parts of pumice powder, 8-12 parts of haydite, 3-8 parts of shell powder, 10-20 parts of palygorskite powder, 5-10 parts of pearl stone powder, 2-5 parts of plant polysaccharide and 0.5-1.5 parts of choline alfoscerate.

2. The dry-mixed mortar additive for preventing cracking and hollowing according to claim 1, wherein the preparation method of the zwitterionic liquid modified dehydroabietylamine comprises the following steps:

step S1, adding N, N-bis (2-hydroxyethyl) -2-aminoethanesulfonic acid and epichlorohydrin into an organic solvent, stirring and reacting for 3-5 hours at 30-40 ℃, then performing rotary evaporation to remove the solvent, washing for 3-5 times by using diethyl ether, and then performing rotary evaporation to remove the diethyl ether to obtain zwitterionic liquid;

and step S2, adding the zwitterionic liquid prepared in the step S1 and the dehydroabietylamine into dimethyl sulfoxide, stirring and reacting for 4-6 hours at 70-80 ℃, and then performing rotary evaporation to remove the dimethyl sulfoxide to obtain the zwitterionic liquid modified dehydroabietylamine.

3. The dry-mixed mortar additive for preventing cracking and hollowing according to claim 2, wherein the mass ratio of the N, N-bis (2-hydroxyethyl) -2-aminoethanesulfonic acid, the epichlorohydrin and the organic solvent in the step S1 is 2.3:1 (10-18), and the organic solvent is one of dichloromethane, tetrahydrofuran and acetone.

4. The anti-cracking empty-bulging dry-mixed mortar additive according to claim 2, wherein the mass ratio of the zwitterionic liquid, the dehydroabietylamine and the dimethyl sulfoxide in the step S2 is 1.07:1 (8-16).

5. The additive for dry-mixed mortar capable of preventing cracking and hollowing according to claim 1, wherein the preparation method of the polyethylene glycol diacrylate/triethoxysilylpropylmaleic acid/N, N' -methylenebisacrylamide copolymer comprises the following steps: adding polyethylene glycol diacrylate, triethoxysilylpropylmaleic acid, N '-methylene bisacrylamide and an initiator into N-methylpyrrolidone, stirring and reacting for 4-6 hours at 70-80 ℃ in the atmosphere of nitrogen or inert gas, precipitating in ethanol, and drying in a vacuum drying oven at 80-90 ℃ to constant weight to obtain the polyethylene glycol diacrylate/triethoxysilylpropylmaleic acid/N, N' -methylene bisacrylamide copolymer.

6. The dry-mixed mortar additive for preventing cracking and hollowing as claimed in claim 6, wherein the mass ratio of the polyethylene glycol diacrylate, the triethoxysilylpropyl maleic acid, the N, N' -methylene bisacrylamide, the initiator and the N-methyl pyrrolidone is 1:2:0.5 (0.03-0.04) to (10-18).

7. The additive for dry-mixed mortar for preventing cracking and hollowing according to claim 6, wherein the initiator is at least one of azobisisobutyronitrile and azobisisoheptonitrile; the inert gas is one of helium, neon and argon.

8. The additive for dry-mixed mortar for preventing cracking and hollowing according to claim 1, wherein the plant polysaccharide is at least one of tea polysaccharide, ginkgo biloba leaf polysaccharide, sugar cane polysaccharide and bamboo leaf polysaccharide.

9. The dry-mixed mortar additive for preventing the cracking and the hollowing as claimed in any one of the claims 1 to 9, wherein the preparation method of the dry-mixed mortar additive comprises the following steps of mixing the components in proportion, adding the mixture into a stirrer to stir for 20 to 30 minutes, grinding the mixture through a 200-mesh and 400-mesh sieve, and discharging the mixture to obtain the dry-mixed mortar additive for preventing the cracking and the hollowing.

10. A dry-mixed mortar containing the crack empty-bulging preventing dry-mixed mortar additive according to any one of claims 1 to 9.

Technical Field

The invention relates to the technical field of building materials, in particular to an anti-cracking empty-bulging dry-mixed mortar additive and dry-mixed mortar containing the same.

Background

In recent years, with the rapid development of economy and the progress of integration of urban and rural areas, various high-rise buildings emerge like bamboo shoots in the spring after rain, and become a mark of modern civilization, and the use of building mortar cannot be left behind these large-scale building projects. The building mortar is an essential main material in building engineering and comprises two forms of dry-mixed mortar and wet-mixed mortar. The dry-mixed mortar is a mortar which is used more at present, and is a granular or powdery material which is formed by physically mixing dry-screened aggregate, an inorganic cementing material, an additive and the like according to a certain proportion, is transported to a construction site in a bag or bulk form, and can be directly used after being mixed with water. However, the dry-mixed mortar in the prior art generally has poor water retention and thixotropy; easy segregation and bleeding, insufficient workability, dryness, difficult scraping, low bonding strength and easy occurrence of hollowing and shedding; large shrinkage, easy surface cracking and the like.

In order to improve the quality of the dry-mixed mortar, the selection of the dry-mixed mortar additive is very important. The dry-mixed mortar additive is a substance blended for improving and adjusting the performance of the mortar, and is an industrial product which is added and mixed into a dry-mixed mortar product according to the specification in a dry-mixed mortar production plant and can improve the normal performance of the cement mortar according to the requirements, such as improving the workability, the water resistance and increasing the strength of the mortar. Common dry-mixed mortar additives include binders, water retention agents, set control agents and plasticizing water reducing agents. However, in order to achieve a better use effect, the dry-mixed mortar additives in the prior art need to be added in a larger amount, which results in high cost, and the common dry-mixed mortar additives have poor effect of improving the mortar performance.

Chinese patent with application number CN201410526207.2 discloses an additive of dry-mixed mortar, which comprises the following components in percentage by mass: 12 to 15 percent of silicon dioxide, 16.5 to 20 percent of aluminum oxide, 10.5 to 14 percent of calcium oxide, 12 to 16.5 percent of magnesium oxide, 8.5 to 12 percent of potassium oxide, 15 to 17.8 percent of sodium oxide and 12 to 15.2 percent of ferric oxide. The additive of the dry-mixed mortar is used in the dry-mixed mortar, so that the step of drying the building aggregate of the dry-mixed mortar is not needed. In addition, the dry-mixed mortar and the preparation method thereof are also provided. However, the above additives have the following problems in preparing dry-mixed mortars: the prepared dry-mixed mortar has low adhesion, is easy to crack and fall off when being used for the wall surface of a building, and can not protect rainwater and ultraviolet rays to influence the service life of the wall surface.

Therefore, the dry-mixed mortar additive which has good comprehensive performance and small addition amount, can effectively prevent wall surface from cracking and hollowing, has obvious improvement effect on the operation hand feeling, the water retention property, the cohesiveness with a base layer, the coordinated deformation property and the like of the mortar meets the market demand, and has higher market value and social value.

Disclosure of Invention

In order to overcome the defects in the prior art, the invention provides the anti-cracking hollowing dry-mixed mortar additive and the dry-mixed mortar containing the additive, the preparation method of the additive is simple and easy, the production formula and the production flow can be simplified, the quality control links are reduced, the additive is more easily dispersed during addition, and the additive is very suitable for large-scale production; the dry-mixed mortar additive prepared by the method has good performance stability and small mixing amount, can effectively improve the water retention rate and cohesiveness of the mortar, and improves the strength of the mortar, cohesiveness with a base layer and cooperative deformation performance; the wall surface can be effectively prevented from cracking and hollowing, and the method has higher economic value, social value and popularization and application value.

In order to achieve the aim, the invention adopts the technical scheme that the anti-cracking and anti-hollowing dry-mixed mortar additive comprises the following components in parts by weight: 5-10 parts of zwitterionic liquid modified dehydroabietylamine, 2-5 parts of polyethylene glycol diacrylate/triethoxysilylpropyl maleic acid/N, N' -methylene bisacrylamide copolymer, 1-3 parts of humic acid, 10-20 parts of pumice powder, 8-12 parts of haydite, 3-8 parts of shell powder, 10-20 parts of palygorskite powder, 5-10 parts of pearl stone powder, 2-5 parts of plant polysaccharide and 0.5-1.5 parts of choline alfoscerate.

Further, the preparation method of the zwitterionic liquid modified dehydroabietylamine comprises the following steps:

step S1, adding N, N-bis (2-hydroxyethyl) -2-aminoethanesulfonic acid and epichlorohydrin into an organic solvent, stirring and reacting for 3-5 hours at 30-40 ℃, then performing rotary evaporation to remove the solvent, washing for 3-5 times by using diethyl ether, and then performing rotary evaporation to remove the diethyl ether to obtain zwitterionic liquid;

and step S2, adding the zwitterionic liquid prepared in the step S1 and the dehydroabietylamine into dimethyl sulfoxide, stirring and reacting for 4-6 hours at 70-80 ℃, and then performing rotary evaporation to remove the dimethyl sulfoxide to obtain the zwitterionic liquid modified dehydroabietylamine.

Preferably, the mass ratio of the N, N-bis (2-hydroxyethyl) -2-aminoethanesulfonic acid, the epichlorohydrin and the organic solvent in the step S1 is 2.3:1 (10-18).

Preferably, the organic solvent is one of dichloromethane, tetrahydrofuran and acetone.

Preferably, the mass ratio of the zwitterionic liquid, the dehydroabietylamine and the dimethyl sulfoxide in the step S2 is 1.07:1 (8-16).

Further, the preparation method of the polyethylene glycol diacrylate/triethoxysilylpropyl maleic acid/N, N' -methylene bisacrylamide copolymer comprises the following steps: adding polyethylene glycol diacrylate, triethoxysilylpropylmaleic acid, N '-methylene bisacrylamide and an initiator into N-methylpyrrolidone, stirring and reacting for 4-6 hours at 70-80 ℃ in the atmosphere of nitrogen or inert gas, precipitating in ethanol, and drying in a vacuum drying oven at 80-90 ℃ to constant weight to obtain the polyethylene glycol diacrylate/triethoxysilylpropylmaleic acid/N, N' -methylene bisacrylamide copolymer.

Preferably, the mass ratio of the polyethylene glycol diacrylate, the triethoxysilylpropyl maleic acid, the N, N' -methylene bisacrylamide, the initiator and the N-methylpyrrolidone is 1:2:0.5 (0.03-0.04) to (10-18).

Preferably, the initiator is at least one of azobisisobutyronitrile and azobisisoheptonitrile; the inert gas is one of helium, neon and argon.

Further, the plant polysaccharide is at least one of tea polysaccharide, ginkgo leaf polysaccharide, sugarcane polysaccharide and bamboo leaf polysaccharide.

The preparation method of the anti-cracking empty-bulging dry-mixed mortar additive is characterized by comprising the following steps: the components are mixed according to the proportion, added into a stirrer and stirred for 20-30 minutes, then milled and sieved by a sieve with 200 meshes and 400 meshes, and discharged, thus obtaining the anti-cracking empty-bulging dry-mixed mortar additive.

A dry-mixed mortar containing the anti-cracking empty-bulging dry-mixed mortar additive.

A dry-mixed mortar containing a dry-mixed mortar additive for preventing cracking and hollowing comprises the following components in parts by weight: 200 parts of Portland cement, 900 parts of building aggregate, 0.0001-0.0005 part of hydroxypropyl methyl cellulose and 6-10 parts of dry-mixed mortar additive.

Further, the building aggregate is a waste red brick, and the length of the building aggregate is 1 mm.

And mixing the portland cement, the building aggregate, the hydroxypropyl methyl cellulose and the dry-mixed mortar additive to obtain the dry-mixed mortar.

Adopt the produced beneficial effect of above-mentioned technical scheme to lie in:

(1) the preparation method of the anti-cracking hollowing dry-mixed mortar additive provided by the invention is simple and feasible, can simplify the production formula and the production flow, reduces the quality control links, is more easily dispersed during addition, and is very suitable for large-scale production.

(2) The anti-cracking hollowing dry-mixed mortar additive overcomes the defects that the traditional dry-mixed mortar additive needs larger additive amount, the cost is high, and the improvement effect on the mortar performance is poor, the prepared dry-mixed mortar additive has good performance stability and small mixing amount, can effectively improve the water retention rate and cohesiveness of the mortar, and improves the strength of the mortar, cohesiveness with a base layer and cooperative deformation performance; the wall surface can be effectively prevented from cracking and hollowing, and the method has higher economic value, social value and popularization and application value.

(3) The anti-cracking hollowing dry-mixed mortar additive provided by the invention is added with the palygorskite powder and the pearl powder, so that the stable performance of the mortar can be ensured, and the mortar has soft expansibility and water-retaining property, so that the mortar becomes soft, plastic and elastic; the plant polysaccharide and the choline alfoscerate act synergistically, so that the hydration of cement can be delayed in the mortar, and then the setting and hardening of the retarded cement are promoted, and the setting time of the cement is regulated and controlled; the pumice powder, the goslarity sand and the shell powder have synergistic effect, so that the mortar coagulation strength can be enhanced, the mortar coagulation time can be shortened, and the building cracking can be effectively prevented; the carboxyl structures on the humic acid and polyethylene glycol diacrylate/triethoxysilylpropylmaleic acid/N, N' -methylene bisacrylamide copolymer are adsorbed on the surfaces of cement particles to ensure that the particles display electrical property, and the particles repel each other due to the same charges, so that the cement particles are dispersed to release redundant moisture among the particles to generate a water reducing effect; on the other hand, due to the existence of the ethoxy silicon on the surface of the cement mortar, an adsorption film is formed on the surface of cement particles, the hydration speed of cement is influenced, the growth of cement stone crystals is more perfect, capillary gaps for water evaporation are reduced, the network structure is more compact, and the hardness and the structure compactness of the mortar are improved.

(4) According to the anti-cracking hollowing dry-mixed mortar additive provided by the invention, the added polyethylene glycol diacrylate/triethoxysilylpropylmaleic acid/N, N' -methylenebisacrylamide copolymer has excellent water absorption and water retention capacity, so that the mortar performance stability is good, the added zwitterionic liquid modifies dehydroabietylamine, and a rosin and zwitterionic liquid structure is introduced, so that the air entraining effect and the bonding effect are good, the adhesion degree of the dry-mixed mortar on a wall surface is improved, and the dry-mixed mortar is prevented from falling off; and the amphoteric structure can promote the rapid progress of hydration reaction, shorten the induction period of the hydration reaction, enable the mortar to have the characteristics of quick hardening and super early strength, shorten the engineering construction time, have the buffering effect on PH, effectively reduce the alkali content of the mortar and avoid the corrosion to metal components caused by the alkali efflorescence of the mortar.

Detailed Description

In order to make the technical solutions of the present invention better understood and make the above features, objects, and advantages of the present invention more comprehensible, the present invention is further described with reference to the following examples. The examples are intended to illustrate the invention only and are not intended to limit the scope of the invention.

The polyethylene glycol diacrylate described in the examples of the present invention, CAS No.: 26570-48-9, cat number: 1027, available from Shanghai light chemical engineering Co., Ltd; other raw materials were all purchased commercially.