KR930009347B1 - Cement compositions - Google Patents

Abstract

The cement-system adhesive composition comprises 100-180 wt.part aggregate to the 100 wt.part cement, 0.01-5 wt.part viscosity- creasing agent, 0.001-5 wt.part plastsizer, 0.1-10 wt.part gypsum, 0.001-5 wt.part anti-foaming agent, 0.02-15 wt.part bond-creasing agent containing 0.01-5 wt.part PVA system copolymer and 0.01-10 wt.part vinylester system copolymer. The composition has a good adhesive force and a good working time.

Description

Cement Based Adhesive Compositions

The present invention relates to cement-based adhesive compositions suitable for adhesion of inorganic tiles, stone or cement secondary products and coating surfaces for waterproofing these products. In general, cement has good adhesion, but cement mixtures which are generally used in cement-water and cement-free water systems are grounded during construction by dehydration in the adhesive layer, especially when the absorbent material has high absorbency. It is difficult to obtain good adhesion due to poor coagulation of the cement mixture.

In order to eliminate such a problem, it is generally known to add and mix cellulose having water solubility to the cement mixture. It gives excellent water retention and plasticity to the water-soluble mixture. In addition, in the cement mixture containing nonionic cellulose ethyl, which is widely used in water-soluble cellulose, much progress has been made in controlling the early curing of the film, which is a problem of lowering the mechanical strength and adhesive strength. Japanese Patent Laid-Open No. 59-155,476 It solves by making degree of substitution of a thickener in arc etc. In addition, PVA is widely used as an additive in which cellulose is used in parallel.

PVA is used to increase adhesive strength, prevent cracking of cement, and control whitening phenomenon. In the case of British Patent No. 1,490,783, a concrete formulation of cement-based adhesive is proposed.

Nevertheless, when the cement mixture containing water-soluble cellulose and PVA is used for bonding inorganic tiles, stone, or cement-based secondary products, the shrinkage of the adhesive increases due to the relative excess of the mixing water. Later, the desired adhesion strength and mechanical strength are not obtained, and this phenomenon is remarkable as the polymerization degree of cellulose increases and the amount of addition increases.

In addition, the mixture of cement-based adhesives require a certain amount of working time until adhering to the adherend after mixing with water. In this case, there is no problem in the case of a relatively short time. There are many inadequate points.

In addition, large pores are generated inside the adhesive, which may act as a cause of lowering the mechanical strength value. As the adhesive of the present method, it is possible to bond inorganic tiles, stone or cement secondary products, but the coating surface for waterproofing these products and PVC organic materials, etc. are not easily bonded.

The present invention is to provide a cement-based adhesive compositions that solve the above conventional problems. 100 to 180 parts by weight of silica, 0.01 to 5 parts by weight of methyl cellulose, 0.01 to 5 parts by weight of PVA, 0.001 to 5 parts by weight of reducing agent, 0.1 to 10 parts by weight of gypsum, 0.001 to 5 parts by weight of antifoaming agent, It is characterized by containing 0.01-10 weight part of vinyl ester copolymers.

The present invention is a cement-based adhesive that exhibits extremely good adhesion to inorganic tiles, stone or cement secondary products, coated surfaces for waterproofing these surfaces, PVC, organic materials, etc., and can easily obtain sufficient working time necessary for construction work. As a result of intensive studies on the composition, it has been found that it is extremely effective to use an appropriate amount of a water reducing agent, an antifoaming agent, and a vinyl ester copolymer in a known cement-silica-cellulose-PVA-based adhesive. The composition of the present invention exhibits excellent adhesion to many kinds of substrates and has a remarkable effect on workability, working time, mechanical properties, rolling, desorption and the like compared to conventional cement-based adhesives.

Hereinafter, the cement adhesive according to the present invention will be described in detail.

For concrete, portland cement, alumina cement, blast furnace cement, etc. were used. Cellulose used methyl cement to improve water retention and workability. The amount of the cement used was 0.01 to 5 parts by weight based on 100 parts by weight of cement. PVA is generally known to increase the adhesive strength and in the present invention is added 0.01 to 5 parts by weight based on 100 parts by weight of cement.

Next, in the silica used as the aggregate, 100 to 180 parts by weight of silica having a particle size of 10 mesh to 325 mesh is added per 100 parts by weight of cement within a range that does not interfere with condensation. Atmospheric shrinkage of cement mortar is mainly caused by evaporation of some of the added water as a physical cause. Therefore, the degree of shrinkage is proportional to the rate of reduction of the weight of the mortar, and if the amount of water added can be reduced, the shrinkage factor is significantly reduced and the shrinkage phenomenon is significantly reduced. In addition, the decrease in the amount of water added has a great influence on the increase in mechanical properties. In order to reduce the amount of water added, the use of a water reducing agent is inevitable, and the water reducing agent used in the present invention has a composition of a lignin sulfonic acid system and simultaneously serves as a dispersion and air entrainment.

The use of such a reducing agent requires the addition of an appropriate amount, rather than the addition of the appropriate amount causes a decrease in mechanical properties. As an appropriate addition ratio thereof, it is 0.001-5 weight part with respect to 100 weight part of cement, Preferably it is 0.001-2 weight part. In addition, the improvement of working time and workability was solved through the condensation delay because gypsum was used in combination with the maintenance effect of methyl cellulose and the control of film early curing. Appropriate amount of gypsum is required to pass the opening time measurement and positioning accuracy standard prescribed in KS L1529 and cause excessive decrease of mechanical property value.

As an appropriate addition ratio thereof, it is 0.1-10 weight part with respect to 100 weight part of cement, Preferably it is 0.1-4 weight part. In addition, the antifoaming agent applied in the present invention uses an alcohol-based, fatty acid ester-based, silicone-based as a method to prevent the mechanical properties due to bubbles generated while mixing the raw material components, which is to remove the bubbles of the mixture to propagate cracks through the bubbles By suppressing the mechanical strength is improved. Antifoaming agent is the main factor that hinders workability when applied to cement adhesives, so the addition of proper ratio is especially necessary. As an appropriate addition ratio thereof, it is 0.001-5 weight part with respect to 100 weight part of cement, Preferably it is 0.001-5 weight part.

The main feature of the present invention is the diversification of additive materials, and in general, cement-based adhesives are used for inorganic tiles, stone, or cement-based secondary products, so they do not adhere well to the surface of coatings or PVC, organic materials, etc. for waterproofing these surfaces. It is not known.

However, in the present invention, the addition of the vinyl ester copolymer enables the adhesion of various substrates.

The vinyl group (CH ₂ -CH-) of the copolymer as an adhesion enhancer generally has an effect of increasing viscosity, thereby providing workability in cement adhesives. In addition, the adhesion enhancer improves the tension and contributes to the improvement of the adhesive force, and at the same time prevents the falling and falling.

The function of adhesion to various substrates can be overcome by imparting plasticity to cement-based adhesives. Lack of plasticity in cement-based adhesives causes microcracks to occur in the matrix, resulting in a loss of force.

In this case, the vinyl ester copolymer may be subjected to a greater load by distributing great plasticity to the cement-based adhesive so as to easily disperse the pressure, and also greatly strengthens the adhesive force, thereby enabling adhesion to these substrates.

Since the proper amount of use is complementary to methyl cellulose and PVA, the amount of addition varies depending on the amount of methyl cellulose and PVA.

In the present invention, it is preferable to use 0.01 to 10 parts by weight, more preferably 0.01 to 8 parts by weight of the adhesive enhancer based on 100 parts by weight of cement.

What is necessary is just to mix | blend an appropriate amount of water with the compound, and knead | mix it, and to use the cement type adhesive agent of such a component, and to use it in a paste state.

The cement adhesive of the present invention will be described in detail with reference to the following examples.

Raw material classification and compounding composition of the cement-based adhesives carried out in the present invention are as follows.

Table 1 shows the results of the cement-based adhesive formulation.

Table 1 Test Results

Note: The test results were conducted according to KSL 1592.

Claims (2)

100 to 180 parts by weight of aggregate, thickener, 0.01 to 5 parts by weight, 0.001 to 5 parts by weight of water reducing agent, 0.1 to 10 parts by weight of gypsum, 0.001 to 5 parts by weight of antifoaming agent, and 0.02 to 15 parts by weight of adhesive enhancer Cement crab adhesive composition, characterized in that. According to claim 1, wherein the adhesion enhancer is characterized in that the PVA and the vinyl ester copolymer is used in 0.01 to 5 parts by weight, 0.01 to 10 parts by weight with respect to 100 parts by weight of cement, respectively.