CS261656B1 - Composition for the preparation of thermal insulation plasters - Google Patents

Abstract

The solution describes a dry composition suitable for the production of thermal insulation plasters. It is based on a mixture of cement, porous fillers, lime hydrate, pre-expanded polystyrene, glass fibers, thixotropic additives and surfactants. Regulation of setting can be achieved by adding accelerators or retarders of cement setting.

Description

261653

BACKGROUND OF THE INVENTION The present invention relates to a composition for the preparation of a cementitious plaster based render.

The thermal insulation plasters based on cement, expanded polystyrene and other additives have found a wide range of applications and are constantly expanding. Addition of pre-expanded polystyrene improves the range of thermal insulation properties of plasters. When treating the respective mortar with a strong hydrophobic character of the polystyrene, it makes it difficult to wet the pre-coated polystyrene particles and coat the cement and other additives with the aqueous composition. Incomplete wetting causes a strong reduction in the mechanical properties of the plasters. Although these properties can be improved by the addition of various polymer dispersions, this method is not applicable to the production of dry plaster compositions which are mixed with water just prior to their application.

These disadvantages are substantially eliminated in the manufacture and use of the compositions of the invention.

The present invention provides a composition for the preparation of cementitious plaster based plasters. The essence of the solution is that the composition consists of 100 wt. dielovcement, 2 to 7 wt. parts of porous anorganic filler from the group of expanded perlite, vermiculite and / or bentonite, 14 to 22 wt. parts of lime hydrate, 5 to 15 wt. parts of pre-calcined or mined polystyrene of up to 5 millimeters, 0.2 to 2 wt. 3 to 30 mm, and an average thickness of 6 to 16 microns, 0.5 to 2.5 wt. parts of a dry thixotropic additive of a group of cellulose derivatives such as carboxymethylcellulose and its salts, cellulose ethers and / or colloidal silicon dioxide, 0.1 to 10 parts by weight of nonionic and / or anionic silicides. If desired, the processing properties can be controlled by the addition of 0.1 to 10 wt. parts of at least one additive of a group of cement solidification regulators and accelerators or retarders, such as calcium chloride, calcium formate, phosphates, polyhydroxy derivatives, and biocidal additives.

As surfactants, a wide variety of compounds such as acyl polyglycol ethers, alkyl phenyl polyglycol ethers, sulphates, phosphates, and the like can be used. . The properties of glass fibers are limited by the following reasons. When using fibers with a thickness greater than 16 microns, they are brittle, crisp and poorly deformable. The use of fibers less than 6 microns in thickness causes problems with their imperfect dispersion in the plaster mass due to the inherent nature.

The surfactants in this case fulfill the function of reducing the surface tension of the water, as a result of which the composition better wets the polystyrene particles while helping! The last of these effects is that the plaster mass has more uniform mechanical and surface properties, i.e., to a lesser extent, the plaster has been broken.

The invention is illustrated by the following examples. Example 1

To a 1.5 kg polystyrene mixer (75 µl. Mixing was added 0.1 kg of fatty acids (C 12 -C 18) oxyethylated with 10 moles of ethylene oxide, 14 kg of cement, 2.5 kg of lime hydrate, 0.45 kg of bentonite, 0.150 kg of expanded perlite, 0.02 kg of methylcellulose, 0.02 kg of sodium carboxymethylcellulose, 0.2 kg of colloidal silica, and 0.1 kg of glass fibers of 6 mm in length and 13 microns in diameter. the composition has a bulk density of 225 kg / m 3, the production of the plaster is carried out by mixing with water and has the following properties: bulk density 280 kg / m 3, thermal conductivity coefficient: 0.082 µn / m 2, pressure strength 1.2 MPa, tensile strength at a bending of 0.48 MPa, the adhesion of the plaster to the concrete substrate after 7 days is 0.15 MPa and after 28 days 0.19 MPa, the stiffening time is 170 minutes and the setting time is 1 250 minutes.

Similar to Example 1, a dry plaster was prepared as a surfactant only, and the sodium polyglycol sulfite sulfate and 0.1 kg of calcium formate were used as accelerators.

Similar to Example 1, a dry plaster composition was prepared using glass fibers of 12 mm length and 16 microns average thickness. As a result, the tensile strength at 0.52 MPa is increased.

Claims (2)

SUBJECT Cement-based composition for the preparation of heat-insulating plasters, characterized in that it consists of 100 wt. parts of cement, 2 to 7 wt. parts by weight of the porous inorganic filler from the group of expanded perlite, vermiculite and / or bentonite; parts. 5 to 15 wt. 0.2 parts by weight of pre-foamed or mineralized polystyrene up to 5 mm in size; parts of glass fibers having a length of 3 to 30 mm and an average thickness of 6 to 16 microns, 0.5 to 2.5 wt. by weight of a thixotropic additive from the group of cellulose derivatives such as carboxymethylcellulose and its salts, cellulose ethers and / or colloidal silicon dioxide, 0.1 to 10 wt. parts of nonionic and / or anionic surfactants. 2. The composition of claim 1 comprising 0.1 to 10 wt. parts of at least one additive from the group of cement solidification regulators as accelerators or retarders such as calcium chloride, calcium formate, phosphates, polyhydroxy derivatives and biocidal additives.