KR100570470B1 - Mortar compositons of gypsum materials - Google Patents

Abstract

The present invention relates to a gypsum-based eco-friendly mortar composition, by producing a mortar using α-half gypsum, or α- natural half gypsum obtained by processing gypsum, chemical gypsum or natural gypsum generated as an industrial by-product as a binder, cement The present invention relates to a gypsum-based eco-friendly mortar composition that significantly improves the disadvantages of low alkalinity, crack generation, and low initial strength of the existing cement mortar.

Gypsum-based eco-friendly mortar composition of the present invention consists of gypsum powder α- hemihydrate gypsum 20 ~ 60% by weight and sand 40 ~ 80% by weight, the gypsum powder is α- hemihydrate gypsum 100 β parts by weight β- hemihydrate gypsum, 0-50 parts by weight of powder selected solely or two or more from the group consisting of II-anhydrite and III-anhydrite are used.

In addition, the gypsum powder is replaced by 0 to 50 parts by weight of powder alone or two or more selected from the group consisting of fly ash, bottom ash, cinder ash, slag, lime powder, silica fume, metakaolin and limestone, based on 100 parts by weight of the gypsum powder. It may be used, with respect to 100 parts by weight of the gypsum powder 0 to 2 parts by weight of resin, 0 to 20 parts by weight of dispersant, 0 to 3 parts by weight of antifoaming agent, 0 to 10 parts by weight of retardant, 0 to 3 parts by weight of thickener. .

Mortar, Composition, α-Half Gypsum

Description

Gypsum-based eco-friendly mortar composition {Mortar Compositons of Gypsum Materials}

The present invention relates to a gypsum-based eco-friendly mortar composition, by producing a mortar using α-half gypsum, or α- natural half gypsum obtained by processing gypsum, chemical gypsum or natural gypsum generated as an industrial by-product as a binder, cement The present invention relates to a gypsum-based eco-friendly mortar composition that significantly improves the disadvantages of low alkalinity, crack generation, and low initial strength of the existing cement mortar.

In general, mortar is used to mix the gypsum to prevent cracking, and the Republic of Korea Patent Publication No. 10-0340296 and the Republic of Korea Patent Publication No. 153247, etc. to add the plaster in the mortar composition to reduce cracking by expansion The method is described. The mortar strength of the gun is obtained by cement, and gypsum is an additive using anhydrous gypsum or dihydrate gypsum only for the purpose of preventing cracking.

In addition, the environment-friendly mortar composition is described in Republic of Korea Patent Application Publication No. 10-2005-0007729, Republic of Korea Patent Publication No. 10-2005-0098417 and Republic of Korea Patent Publication No. 10-2005-0029940. Cement is used as a binder of the dry mortar, and minerals such as germanium, sericite, elite or loess are used as environmentally friendly materials.

In the prior art, cement is used as a binder and anhydrous gypsum or dihydrate gypsum is used for the purpose of cracking as one of the additives. In general cement mortar, shrinkage occurs due to hydration of cement or drying of mortar, and cracking occurs due to such shrinkage. The occurrence of cracks has a problem of peeling because not only the appearance but also the adhesion to concrete is weakened.

At the construction site, water is often used excessively due to the convenience of work when pouring mortar. Such mortar causes excessive bleeding, greatly delaying the finishing work of mortar, and problems such as reduced strength and cracking. This is caused.

Accordingly, the present invention has been made to solve the above conventional problems,

An object of the present invention is a gypsum mortar using a mixture of β-half gypsum, Ⅱ- anhydrite gypsum, and Ⅲ- anhydrite gypsum in order to improve the disadvantages of low alkalinity, cracking and initial strength of cement mortar. To provide a composition.

Gypsum-based eco-friendly mortar composition of the present invention for achieving the above object,

Gypsum powder is composed of α- hemihydrate gypsum 20-60% by weight and sand 40-80% by weight, the gypsum powder is β- hemihydrate gypsum, Ⅱ- anhydrite gypsum, Ⅲ- anhydrite gypsum with respect to 100 parts by weight of α- hemihydrate gypsum 0-50 parts by weight of at least one powder selected from the group consisting of

In addition, 1 to 50 parts by weight of powder selected solely or two or more from the group consisting of ganbanite, germanium, sericite, illite, loess and titanium oxide may be used with respect to 100 parts by weight of sand.

In addition, the gypsum powder is replaced by 1 to 50 parts by weight of powder alone or two or more selected from the group consisting of fly ash, bottom ash, cinder ash, slag, lime powder, silica fume, metakaolin, and limestone based on 100 parts by weight of the gypsum powder. It is used, 0.1 to 2 parts by weight of resin, 0.1 to 20 parts by weight of dispersant, 0.1 to 3 parts by weight of defoaming agent, 0.1 to 10 parts by weight of retardant, and 0.1 to 3 parts by weight of thickener based on 100 parts by weight of the gypsum powder. .

The α-half gypsum can be prepared by processing gypsum, chemical gypsum and natural gypsum generated as an industrial by-product, it can be used as it is natural hemihydrate gypsum. α-Half gypsum may contain a small amount of II-anhydrite, Ⅲ-anhydrite and / or β-half-hydrate, but even a small amount of gypsum is not good for physical properties such as abnormal quenching, increase of mixed quantity and deterioration of strength. It is desirable to remove it since it affects.

The method for producing α-half gypsum from dihydrate gypsum includes an atmospheric aqueous solution method, a pressurized hydrothermal method, a microwave method, and a hybrid hydrothermal reaction method. The atmospheric aqueous solution method is prepared by heating dihydrate gypsum with a catalyst under an aqueous solution at 100 ° C. and atmospheric pressure. Pressurized hydrothermal method is prepared by using an autoclave reactor at a temperature of 100 ~ 150 ℃, microwave method is prepared by irradiating microwave to the temperature of 120 ~ 140 ℃ in a molded body of hydrated gypsum. Hybrid hydrothermal method is a manufacturing method that can perform pressurized hydrothermal method and microwave method at the same time. It can shorten the long reaction time of pressurized hydrothermal method and reduce external diffusion speed of the molded product which can occur when using microwave only. There is this.

For the α-half gypsum prepared by this process, it is preferable to use 20% by weight to 60% by weight in the mortar composition. In the above case, better physical properties can be obtained, but the mortar manufacturing cost is high, which is uneconomical.

In addition, since the gypsum powder enhances abrasion resistance of the mortar and imparts moderate viscosity to the mortar, the resin is further added in order to give a stable adhesive force during plastering or painting because it exhibits resistance to material separation and excellent adhesion even when highly hydrophilized. Can be.

The resin to be added may be polyethylene fiber, polypropylene fiber, glass fiber, silica fiber, etc. as the insoluble resin, and polyacrylic acid (sodium), polymethacrylic acid (sodium), polymaleic acid (sodium) ), Unsaturated carboxylic acid polymers such as sodium salt of acrylic acid-maleic acid copolymer; Polymers of polyoxyethylene or polyoxypropylene such as polyethylene glycol, polypropylene glycol, or copolymers thereof; Nonionic cellulose ethers such as methyl cellulose, ethyl cellulose, hydroxymethyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, carboxyethyl cellulose and hydroxypropyl cellulose; Polysaccharides produced by microbial fermentation such as yeast glucan, xanthan gum, and β-1,3 glucans (any of linear and branched chains); Polyacrylamide; Polyvinyl alcohol; Starch; Starch phosphate ester; Sodium alginate; gelatin; The copolymer of acrylic acid which has an amino group in a molecule | numerator, its quaternary compound, etc. are mentioned.

As the dispersant, ordinary water reducing agents can be used. For example, lignin sulfonate, polynaphthalene sulfonate, polymelamine sulfonate, or a polycarboxylate-based group may be used alone or in combination of two or more.

The dispersant is used to secure the required workability by increasing the fluidity of the mortar composition, Ⅱ- anhydrite gypsum, α- anhydrite gypsum, Ⅲ- anhydrite gypsum, β- hemihydrate gypsum, etc. It is preferable to use 20 parts by weight or less based on 100 parts by weight of the gypsum powder in the form in which the inorganic powder of. If it is more than 20 parts by weight, it is not economical because it is not expected to greatly improve the dispersibility compared to the amount of use, and may cause bleeding and excessive coagulation delay.

Next, the antifoaming agent is used to remove the large pores in the mortar to improve the strength and appearance of the mortar. Defoamers include mineral oil-based defoamers such as kerosene, liquid paraffin, and the like; Oil-based antifoaming agents such as animal and vegetable oils, sesame oil, castor oil and their alkylene oxide adducts; Fatty acid-based antifoaming agents such as oleic acid, stearic acid and alkylene oxide adducts thereof; Fatty acid ester antifoaming agents such as glycerin monolicinolate, alkenyl amber acid fluid, sorbitol monolaurate, sorbitol trioleate, natural wax and the like; Polyoxyalkylenes, (poly) oxyalkyl ethers, acetylene ethers, (poly) oxyalkylene fatty acid esters, (poly) oxyalkylene sorbitan fatty acid esters, (poly) oxyalkylene alkyl (aryl) ethers Oxyalkylene antifoaming agents such as sulfuric acid ester salts, (poly) oxyalkylene alkyl phosphate esters, (poly) oxyalkylene alkylamines, and (poly) oxyalkylene amides; Alcohol antifoaming agents such as octyl alcohol, hexadecyl alcohol, acetylene alcohol, glycols, and the like; Amide antifoaming agents such as acrylate polyamine; Phosphate ester defoaming agents such as tributyl phosphate and sodium octyl phosphate; Metal soap-based antifoaming agents such as aluminum stearate and calcium oleate; Silicone antifoaming agents such as dimethylsilicone oil, silicone paste, silicone emulsion, organomodified polysiloxane (polyorganosiloxane such as dimethylpolysiloxane), fluorosilicone oil and the like can be used.

In addition, the retardant may be added to delay the quickness of the α-half gypsum and to ensure workability for a certain period of time.

Examples of the retardant include oxycarboxylic acids such as inorganic salts or organic salts such as gluconic acid, citric acid, tartaric acid, glucoheptonic acid, arabic acid, malic acid or citric acid, and sodium, potassium, calcium, magnesium, ammonium and triethanolamine; Monosaccharides such as glucose, fructose, galactose, saccharose, xylose, abitose, lipoose and isosaccharides, oligosaccharides such as disaccharides and trisaccharides, oligosaccharides such as dextrins, and polysaccharides such as dextran, Sugars such as molasses containing these; Sugar alcohols such as sorbitol; Magnesium silicate; Phosphoric acid and its salts or boric acid esters; Aminocarboxylic acids and salts thereof; Alkali soluble protein; Fuminic acid; Tannic acid; phenol; Polyhydric alcohols such as glycerin; Aminotri (methylenephosphonic acid), 1-hydroxyethylidene-1,1-diphosphonic acid, ethylenediaminetetra (methylenephosphonic acid), diethylenetriaminepenta (methylenephosphonic acid) and alkali metal salts thereof, alkali Phosphonic acids such as earth metal salts and derivatives thereof.

Other additives include waterproofing agents such as fatty acids (salts), fatty acid esters, fats and oils, silicones, paraffins, asphalt and waxes; Rust inhibitors such as nitrite, phosphate and zinc oxide; Cracking agents such as alkanediols such as polyoxyalkyl ethers and 2-methyl-2,4-pentanediol, and silicyl fluoride salts; Expansion materials such as calcium sulfoaluminate, coal, and quicklime systems; Soluble calcium salts such as calcium chloride, calcium nitrite, calcium nitrate, calcium bromide, calcium iodide, chlorides such as iron chloride and magnesium chloride, formates such as sulfate, potassium hydroxide, sodium hydroxide, carbonate, thiosulfate, formic acid and calcium formate, Adjuvants or accelerators, such as an alcohol amine, an alumina cement, calcium aluminate silicate, etc. can be used.

In addition, we can add auxiliary materials to improve the mortar's functionality as wetting agents, thickeners, separation agents, flocculants, dry shrinkage reducers, strength enhancers, self-leveling agents, rust inhibitors, colorants, antibacterial or antifungal agents, blast furnace slag , Fly ash, cinder ash, clinker ash, hask ash, silica fume, silica powder, limestone powder and the like.

The gypsum mortar in which the above materials are mixed in an appropriate ratio is less environmentally friendly than strong alkaline materials such as cement because of less cracking, better appearance, and near pH neutrality than cement mortar. In addition, since the strength is excellent in the early age (within 24 hours), it is possible to reduce the construction cost due to early construction. The use of dispersants and thickeners in suitable proportions makes it possible to produce mortars with self-leveling performance.Because they have good viscosity compared to cement mortars, they have the advantage of reducing cracking due to shrinkage and shrinkage due to high fluidization. Have.

Examples of the present invention are described below, but these are for illustrative purposes and do not limit the scope of the present invention.

In the following examples and comparative examples, mortar was mixed according to the mechanical mixing method of the hydraulic cement paste of KS L 5109 and mortar, and the solidification time of the mortar was measured according to the concrete solidification time test method by penetration resistance needle of KS F 2436. The compressive strength of mortar was measured at 1 and 3 days of age, respectively, according to the compressive strength test method of hydraulic cement mortar of KS L 5105.

Example 1

510 parts by weight of α-half gypsum (GIMENT-α100, hard gypsum of Yusung Tech Co., Ltd.), 1250 parts by weight of standard yarn (weight ratio of gypsum and standard yarn is 1: 2.45) and solids per gypsum weight of dispersant (polycarboxylate) Gypsum-based mortar was prepared by adding 0.50 wt% based on the standard. The mortar was prepared by administering water to the mortar so that the ratio of water / gypsum was 47%.

Example 2

510 parts by weight of α-half gypsum (GIMENT-α200, super hard gypsum of Yusung Tech Co., Ltd.), 1250 parts by weight of standard yarn (weight ratio of gypsum and standard yarn is 1: 2.45) and dispersant (polycarboxylate) per gypsum weight Gypsum-based mortar was prepared by adding 0.55% by weight based on solids. The mortar was prepared by administering water to the mortar so that the ratio of water / gypsum was 48%.

Example 3

α-Half Gypsum (GIMENT-α100 of Yusung Tech Co., Ltd.) 510 parts by weight, 1250 parts by weight of standard yarn (weight ratio of gypsum and standard yarn is 1: 2.45), citric acid and dispersant (polycarboxylate system) Gypsum-based mortar was prepared by adding 0.5 wt% and 0.48 wt%, respectively, based on the solid content per gypsum weight. The mortar was prepared by administering water to the mortar so that the ratio of water / gypsum was 45%.

Comparative Example 1

510 parts by weight of cement (usually one Portland cement), 1250 parts by weight of standard yarn (weight ratio of cement and standard yarn is 1: 2.45) and 0.50% by weight of dispersant (polycarboxylate) based on solids per weight of cement Mortar was prepared. The mortar was mixed with water so that the water / cement ratio was 45%, and the mortar was mixed.

Comparative Example 2

510 parts by weight of cement (usually one Portland cement), 1250 parts by weight of standard yarn (weight ratio of cement and standard yarn is 1: 2.45), gluconic acid and dispersant (polycarboxylate) based on solids per weight of cement Cement mortar was prepared by adding 0.25 wt% and 0.48 wt%, respectively. The mortar was mixed with water so that the water / cement ratio was 45%, and the mortar was mixed.

Table 1 shows the mortar test results of Examples 1-3 and Comparative Examples 1 and 2.

[Table 1] Mortar test results

Comparing the gypsum-based mortars obtained in Examples 1 to 3 and the cement-based mortars obtained in Comparative Examples 1 and 2, the workability (flow) of the mortars tends to be slightly lower than that of gypsum-based mortars, but it is compressed at an early age. Intensity expression was found to be very large. When the retardant is not used as in Examples 1 and 2, the setting time is very fast and the strength is developed at an early age, which is suitable for repairing and reinforcing the mortar. In addition, when using a retardant as in Example 3, it is possible to ensure a very effective working time, it is possible to pour a large amount of mortar. In addition, as a result of measuring the pH of the dry mortars prepared in Examples 1 to 3 and Comparative Examples 1 and 2 as a 20% slurry, cement-based mortars showed very strong alkalinity, but gypsum-based mortars were almost environmentally friendly. It can be confirmed that the material.

In addition, the above-mentioned example is only an example to demonstrate this invention. Therefore, it is obvious that the ordinary skilled in the art to which the present invention pertains uses the partial change with reference to the detailed description.

As described above, the gypsum-based eco-friendly mortar composition of the present invention,

The high compressive strength at early age and the fastening time without mixing the retardant are suitable for repair and reinforcement of mortar, and it is possible to place a large amount by mixing the retardant. It is possible to provide a mortar composition that can be used by the operator stably, and to prevent environmental destruction by the remaining material.

Claims (5)

Gypsum powder is composed of α- hemihydrate gypsum 20-60% by weight and sand 40-80% by weight, the gypsum powder is β- hemihydrate gypsum, Ⅱ- anhydrite gypsum, Ⅲ- anhydrite gypsum with respect to 100 parts by weight of α- hemihydrate gypsum Gypsum-based eco-friendly mortar composition, characterized in that 1 to 50 parts by weight of the powder alone or two or more selected from the group consisting of. The method of claim 1, Gypsum-based eco-friendly mortar composition, characterized in that 1 to 50 parts by weight of powder selected solely or two or more selected from the group consisting of ganbanite, germanium, sericite, illite, ocher, titanium oxide with respect to 100 parts by weight of sand. The method according to claim 1 or 2, The gypsum powder is replaced by 1 to 50 parts by weight of powder selected solely or two or more from the group consisting of fly ash, bottom ash, cinder ash, slag, lime powder, silica fume, metakaolin, and limestone based on 100 parts by weight of Gypsum-based environmentally friendly mortar composition. The method according to claim 1 or 2, 0.1 to 2 parts by weight of resin, 0.1 to 20 parts by weight of dispersant, 0.1 to 3 parts by weight of antifoaming agent, 0.1 to 10 parts by weight of retardant, and 0.1 to 3 parts by weight of thickener, based on 100 parts by weight of the gypsum powder. Gypsum-based eco-friendly mortar composition. The method of claim 3, wherein 0.1 to 2 parts by weight of resin, 0.1 to 20 parts by weight of dispersant, 0.1 to 3 parts by weight of antifoaming agent, 0.1 to 10 parts by weight of retardant, and 0.1 to 3 parts by weight of thickener, based on 100 parts by weight of the gypsum powder. Gypsum-based eco-friendly mortar composition.