Water-repellent admixture for mortar and concrete

Abstract

The invention discloses a water-repellent admixture for mortar and concrete. The water-repellent admixture for mortar and concrete is compounded of organosilicone emulsion, water, a concrete shrinkages reducing agent, a defoaming agent, a water reducing agent, a cement hydrating accelerant, a lithium compound and an air entraining agent, wherein the organosilicone emulsion is of a core-shell structure and prepared by soap-free polymerization and the particle size of emulsion particle is less than 200nm. When 1% of water-repellent admixture is added to mortar, the permeable pressure ratio of the obtained water-repellent mortar layer is not less than 420%, and the water absorption capacity within 48 hours is not greater than 48%; and when 0.2% of water-repellent admixture is added to concrete, the permeable height ratio of the obtained water-repellent concrete layer is not greater than 15%, the water absorption capacity within 48 days is not greater than 26%, and the shrinkage ratio within 28 days is not greater than 102%. The water-repellent admixture contains a core-shell spherical particle polymer with nanoscale and also contains shrinkages reducing agent, air entraining agent, lithium salt and other compounds which have different functions, and thus the anti-permeability, the water-repellent performance and the durability of the water-repellent layer can be greatly improved, the cracking can be avoided, and the toughness is also improved; and the water-repellent admixture is safe, nontoxic, simple in production, environment-friendly, low in cost, simple in structure, and short in open time.

Description

technical field [0001] The invention belongs to the technical field of mortar concrete waterproofing agent, in particular to a mortar concrete waterproofing agent. Background technique [0002] Waterproof engineering occupies a very important position in construction engineering. In the practice of construction engineering, quality accidents caused by unreasonable waterproof engineering design, improper material selection, and rough construction are not uncommon, and light ones cause roof and joint leakage and paint peeling off; Seriously, it causes underground works to be submerged in water, and even buildings collapse, causing losses to state property and endangering people's lives. Therefore, the waterproofing project must be implemented and guaranteed with high quality. [0003] The quality of waterproof materials is one of the most critical links for high-quality implementation and protection of waterproof projects. After years of development, waterproof materials can...

AI Technical Summary

Problems solved by technology

However, it is a pity that although the current waterproofing agent market has many product specifications, the products are not only chaotic in price, but also have great defects in quality, which greatly affects the use effect

For example, fatty acid salts are added to some waterproofing agent products, which will reduce the strength of mortar and concrete layers by about 25%; The strength of the waterproof layer has been reduced by at least 26%. The method of adding a water reducing agent to reduce the water consumption is used to increase the strength. Although the effect is achieved, the workability of the water reducing agent and mortar concrete is strictly controlled. This method Not desirable in engineering applications

There are also small molecular organosilicon compounds added to some waterproofing agent products (Guo Qingzhong. Research and Development of Organosilicon Fluorine Building Waterproof and Dustproof Materials. Postdoctoral Dissertation of Sun Yat-Sen University. 2007), which not only makes the formed waterproof layer have very good alkali resistance Poor, resulting in a short life of the waterproof layer, but also greatly delayed the opening time of construction, the formed waterproof layer sometimes as long as two days without hardening

Another example is the technical solution disclosed in the Chinese patent CN103073214A, which simply adds inorganic silicon compounds, expansion agents, inorganic aluminum salts and other substances to achieve the effect of filling and compacting. The application range of these products is limited, and the waterproof and impervious properties Poor, poor durability of waterproof layer, easy to crack

In addition, although the silicone waterproof emulsion prepared by foreign giants such as Wacker and Degussa has good performance, the price is high, which is not conducive to promotion

[0004] Therefore, existing waterproofing agent products have low construction waterproofing layer strength, long opening time, poor waterproofing performance, short life, high price, complex production and construction techniques, etc., which have become bottleneck problems urgently to be solved in the promotion of waterproofing agents

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