RU2237037C1 - Dry mix - Google Patents

Abstract

FIELD: manufacture of building materials.

SUBSTANCE: dry mix suitable for finishing operations contains, wt %: gypsum 99.35-99.54, retardant 0.008-0.15, cellulose ether 0.19-0.25, and re-dispersed latex powder 0.19-0.25.

EFFECT: retarded initial setting time and reduced setting duration.

2 tbl

Description

The invention relates to the production of building mixtures, in particular to obtaining dry building mixtures for the production of finishing work.

Known gypsum mixture according to patent No. 2090533 (publ. 09/20/97), including semi-aquatic gypsum and the addition of alkaline effluents for the production of caprolactam based on dicarboxylic acids SHCHSPK, it additionally contains a multidentate chelating ligand and trisodium phosphate in the following ratio, wt.%: Semi-aquatic gypsum 47 -72; the addition of alkaline effluents for the production of caprolactam based on dicarboxylic acids ShchSPK 0.2-0.8; multidental chelating ligand 0.03-0.15; trisodium phosphate 0.05-0.1; water the rest.

The described composition has the following disadvantages: the stability of the composition due to its water-emulsion state is limited, the resulting coating has low adhesive strength.

The closest analogue of the invention is a dry gypsum plaster mixture, which contains a gypsum binder, sand from expanded vermiculite, lime, a moderator is citric acid, etherocellulose in the form of carboxymethyl cellulose, an air-entraining additive is sulfonol, superplasticizer, (see, 2001 No. 115.02, publ. , 4 pp.).

The present invention solves the problem of creating a dry mixture with an extended start time of the setting process and a reduced setting time.

To achieve the specified technical result, a dry stucco mixture, including gypsum, a moderator, ether cellulose, additionally contains redispersed latex powder in the following ratio, wt.%:

Gypsum 99.35-99.54

Retarder 0.08-0.15

Ether cellulose 0.19-0.25

Redispersed latex powder 0.19-0.25

The mixture according to the invention has an increased start time of the setting process and a reduced setting time, which allows the gluing of drywall sheets, expanded polystyrene plates and other materials onto substrates with a hygroscopic surface. With an uneven surface of the base, the mixture must be applied to a drywall sheet or other material with a step of 35 cm, with large irregularities, the surface of the base must be leveled with drywall strips.

A dry mixture is obtained by mixing gypsum with special additives. As a delaying setting time, additives are used, for example, Plast Retard, citric acid or anhydrite. The composition introduced additives to give plasticizing and water-holding ability. As gypsum, semi-aquatic gypsum or anhydrite is used. Expanded perlite is used as perlite, carboxymethyl cellulose or tylose as cellulose ether.

The solution is prepared as follows: pour the mixture into clean cold water in a ratio of 1: 0.55 and mix to a homogeneous (without lumps) consistency manually or using a mixer.

The setting time of the solution depends on the surface being treated. The start time of the setting of the mortar mixture (including preparation, application and grouting) is 120 ± 10 minutes from the beginning of mixing. The setting time is 30 minutes from the start of setting. The mixture does not emit harmful chemicals into the environment and belongs to class 1 in terms of the specific effectiveness of natural radionuclides.

Claims (1)

Dry stucco mixture, including gypsum, a moderator, etirocellulose, characterized in that it contains an additional redispersed latex powder in the following ratio, wt.%: Gypsum 99.35-99.54 Retarder 0.08-0.15 Ether cellulose 0.19-0.25 Redispersed latex powder 0.19-0.25