RU2531078C2 - Mixture for obtaining heat-insulating material - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to raw material mixtures for obtaining a heat-insulating material, which is applied for the production of heat-insulating coatings of pipelines with cooling media in nuclear and thermal power plants. A composition for obtaining the heat-insulating material includes a binding agent, a silica-containing filler, sodium fluorosilicate and polyethyleneglycol, as the binding agent it contains a water solution of sodium polysilicate with the silicate modulus 4.2, obtained by the introduction of 10% hydrosol of silicon dioxide into a 30% water solution of sodium silicate with their ratio of 1:1, mixing at 100°C for 3.0 h with the following exposure at the said temperature 0.4, and the said filler - milled gaize with the following component ratio, wt %: water solution of sodium polysilicate 100, milled gaize 0.01-45, sodium fluorsilicate 10-40, polyethylorganosilicone 5-25.

EFFECT: reduction of density and the thermal conductivity coefficient.

1 ex, 1 tbl

Description

The invention relates to compositions for producing a heat-insulating material based on liquid glass, used for the device of heat-insulating coatings of pipelines with coolants in nuclear and thermal power plants.

Known composition [1] for the manufacture of thermal insulation, including, wt.%:

Liquid glass 45-50 Quartz Ground Sand 43.5-53.0 Sodium silicofluoride 1-5 Intumescent Additive 0.05-0.5 Lime Fluff 0.55-1.0

The disadvantage is the rapid expansion of the composition, which does not allow to obtain a monolithic thermal insulation coating.

The closest is the composition [2] to obtain a thermal insulation material, comprising the following components, parts by weight:

Liquid glass one hundred Ground sand 0.01-45 Sodium silicofluoride 10-40 Polyethylorganosilicon 5-25.

The disadvantage of this composition is the high density and thermal conductivity, therefore, low heat-insulating ability.

A decrease in the density and thermal conductivity is achieved by the fact that the composition for thermal insulation, including water glass, ground sand, sodium silicofluoride and a blowing agent - polyethylorganosilicon, contains sodium polysilicate with module 4.2 as a binder, and instead of ground sand, silica contains a flask with specific a surface of 2500-3000 cm ² / g in the following ratio of components, parts by weight:

Sodium Polysilicate Aqueous Solution one hundred Ground flask 0.01-45 Sodium silicofluoride 10-40 Polyethylorganosilicon 5-25

To compare the properties of the proposed composition with a known composition of the ratio of the components in the examples were taken similarly known. Additionally, for the known compositions, the thermal conductivity was also determined.

Sodium polysilicate with module 4.2 was obtained in the laboratory, according to US Pat. 2124475 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

Example 1

In 100 parts by weight an aqueous solution of sodium polysilicate was introduced 0.01 wt.h. ground flask with a specific surface of 2500-3000 cm ² / g, the mixture was stirred, was added to it 15 parts by weight polyethylorganosilicon and again mixed. Then added 10 parts by weight silicofluoride and after thorough mixing the prepared composition was poured into molds. A day later, the finished insulation material has the following properties: average density - 520 kg / m ³ ; thermal conductivity coefficient - 0.12 W / (mK).

Similarly, examples 2-5 were also performed, for which the ratio of components in the raw mix and the properties of the heat-insulating material based on them are given in the table.

Components and Features Proposed Famous Examples Examples one 2 3 four 5 one 2 3 four 5 Liquid glass, parts by weight one hundred one hundred one hundred one hundred one hundred Sodium polysilicate, parts by weight one hundred one hundred one hundred one hundred one hundred Ground sand, parts by weight 0.01 twenty 45 45 45 Ground flask, mass.h. 0.01 twenty 45 45 45 Silicon fluoride, mass parts 10 10 10 25 40 10 10 10 25 40 Polyethylorganosilicon, parts by weight fifteen fifteen fifteen fifteen fifteen fifteen fifteen fifteen fifteen fifteen Density, kg / m ³ 520 600 710 820 830 650 720 850 970 970 Thermal conductivity, W / (mK) 0.12 0.14 0.18 0.20 0.22 0.15 0.19 0.24 0.32 0.33

An analysis of the results given in Table 1 shows that when sodium polysilicate with module 4.2 is used instead of liquid glass, and instead of ground sand of the active siliceous component, with ground flask, the density and thermal conductivity of the obtained heat-insulating material are significantly reduced. Therefore, the proposed thermal insulation material has a higher heat-insulating ability than the known one.

Information sources

1. USSR author's certificate No. 443011, cl. C04B 19/04, 1972.

2. USSR author's certificate No. 706383, cl. C04B 19/04, 1979.

Claims (1)

Composition for producing a heat-insulating material, including a binder, silica-containing filler, sodium silicofluoride and polyethylorganosilicon, characterized in that it contains an aqueous solution of sodium polysilicate with a silicate module 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 - ground flask in the next the ratio of components, mass.h:
Sodium Polysilicate Aqueous Solution one hundred Ground flask 0.01-45 Sodium silicofluoride 10-40 Polyethylorganosilicon 5-25