RU2531079C2 - Composition for production of heat insulation material - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to industry of construction materials and may be used for production of non-baked heat insulation materials, used for insulation of buildings, structures and pipelines. A composition for production of a heat insulation material, including a binder, a silica-containing filler and boric acid, the binder is an aqueous solution of sodium polysilicate with a silicate module 4.2, produced by introduction of 10% silicon dioxide hydrosol into 30% aqueous solution of sodium silicate with their ratio of 1:1, mixing at 100°C for 3.0 hrs with subsequent soaking at this temperature for 0.4 hrs, and the specified filler - finely ground diatomite at the following ratio of components, wt %: aqueous solution of sodium polysilicate 92.0-95.5, diatomite 1.5-3.0, boric acid 3-6.

EFFECT: increased compression strength and reduced density of a heat insulation material.

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Description

The invention relates to the production of heat-insulating materials used for insulation of buildings, structures and pipelines.

A known composition for producing heat-insulating materials, including water glass, dry silica and the addition of sodium silicofluoride [1].

The disadvantage of this composition is the high density, as well as the duration of the technological cycle of manufacturing materials.

Closest to the proposed one is a composition for producing a heat-insulating material [2], including water glass, dry silica and an additive boric acid in the following ratio of components, wt.%:

Liquid glass 92.0-95.5 Dry silica 1.5-4.0 Boric acid 3.0-6.0

The disadvantage of this composition is the low compressive strength and average density.

An increase in compressive strength and a decrease in the density of the heat-insulating material is achieved by the fact that the composition comprising liquid glass, dry silica and boric acid as a binder contains an aqueous solution of sodium polysilicates, and instead of dry silica - active silica - diatomite with a specific surface of 2500-3000 cm ² / g in the following ratio of components, wt.%:

Sodium Polysilicate Aqueous Solution 92.0-95.5 Diatomite 1.5-3.0 Boric acid 3-6

In laboratory conditions, an aqueous solution of sodium polysilicate with module 4.2 was prepared, which according to US Pat. RF №2124475, obtained by introducing into a 30% aqueous solution of sodium silicate 10% hydrosol of silicon dioxide at a ratio of 1: 1, stirring at 100 ° C for 3.0 hours, followed by exposure to 0.4 at this temperature hours

Then, in the obtained solution of sodium polysilicate with module 4.2 with vigorous stirring with a propeller stirrer (at least 600 rpm), we introduce dry powdered boric acid and diatomite with a specific surface of 2500-3000 cm ² / g to obtain a homogeneous mixture (1-2 min ) The finished mixture was poured into a hot metal mold with a perforated lid and kept at 300-350 ° C for 20-45 min.

After cooling, the mold was opened and finished products were removed. Examples of compositions and properties of the obtained products are given in table 1.

The use of sodium polysilicate solution instead of water glass, therefore, increasing the silicate module (CM = 4.2) of the binder, together with dry fine-ground diatomite accelerates the expansion process, which, in turn, allows to obtain low-density thermal insulation products. In addition, diatomite - active silica reacts with sodium polysilicate, forming high-modulus adhesives with high adhesive and cohesive properties, as evidenced by the strength characteristics of the proposed thermal insulation material.

Thus, the use of a solution of sodium polysilicate and dry diatomite in a quantitative ratio makes it possible to obtain a heat-insulating material with high compressive strength and low water absorption.

Table 1 Components and Features Proposed Famous 2 3 four 10 eleven 12 Liquid glass 92.5 93.0 95.2 Sodium polysilicate 92.5 93.0 95.2 Dry silica 1.5 3.0 2.0 Boric acid 6.0 4.0 3.0 6.0 4.0 3.0 Diatomite 1.5 3.0 2.0 Density, kg / m ³ 160 145 120 202 182 179 The limit of compressive strength, MPa 0.960 0.750 0.890 0.497 0.374 0.413 Water absorption,% 7.4 7.8 6.9 9.2 9.4 9.0

Information sources

1. Grigoriev P.N. Soluble glass. -M., Promstroyizdat, 1966, p. 321-323.

2. USSR copyright certificate No. 863575, class. C04B 43/00, C04B 19/04, 1981.

Claims (1)

A composition for producing a heat-insulating material, comprising a binder, silica-containing filler and boric acid, characterized in that it contains as a binder an aqueous solution of sodium polysilicate with a silicate module of 4.2, obtained by introducing into a 30% aqueous solution of sodium silicate 10% - hydrosol of silicon dioxide at a ratio of 1: 1, stirring at 100 ° C for 3.0 hours, followed by exposure at this temperature for 0.4 hours, and the specified filler is finely ground diatomite in the following ratio of components, wt.%:
Sodium Polysilicate Aqueous Solution 92.0-95.5 Diatomite 1.5-3.0 Boric acid 3-6