SU1209896A1 - Composition for isolating structures in mines - Google Patents

Description

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The invention relates to mountain pelle, and specifically to compositions for the construction of insulating structures and plugging of domes 9 for the purpose of preventing endogenous fires during mining of spontaneously heated coal, and can also be used to insulate mine workings.

The purpose of the invention is to increase the strength of insulating structures and reduce their air permeability.

The introduction of a 257 $ aqueous solution of a polyacrylamme gel-like solution makes it possible to obtain a high-quality foam of a homogeneous structure due to the fact that the physical properties of the solution are close to resin (density 1.44-1.47 g / cm-and conditional viscosity at 20+ 0, 5 With the VZ-4 viscometer 15-20 s).

Air permeability of samples made on the basis of the proposed composition is within

0.032-0.055 against 0.075 mVmin.

The fragility of the samples is characterized by a change in the height of the sample without damage to 85% against 40%.

The choice of the concentration of 25% solution of polyacrylamide is justified: the fact that such a solution is closest in its physical properties to the resin and ensures the homogeneity of the structure. At another concentration value, the uniformity of the structure worsens, moreover, a decrease in the concentration of the solution leads to a sharp increase in shrinkage.

Adding a 25% aqueous solution of a gel-like polyacrylamide of less than 10 wt.% Does not have a significant effect on breathability, and an increase of more than 20 wt.% Leads to an increase in the cure time from 20 to 60 minutes, which exceeds the stability time of the foam and can lead to its destruction before curing, i.e. reduce the quality of the foam.

Example 1. To obtain 1 kg of a composition with a content of a 25% aqueous solution of a gel-like polyacrylamide in an amount of 10% by weight, the components are weighed in the following quantity, g:

63% water

urea-formaldehyde solution

resin400 ,, o

098962

25% aqueous solution of gel-like polyacrylamide 100.0 Frother, (triethanolamine

salt of lauryl sulfate) 6,1 Hardener (orthophosphoric acid) 20.4 Water Else

} Q The foaming agent, hardener and water (ABO) are mixed with a laboratory mechanical frame mixer for 2 minutes until a stable foam is obtained. Without discontinuing the stirring, a 63% aqueous solution is added 15. urea-formaldehyde resin in a quantity of 40 wt.%, which is pre-mixed with 10 wt.% gel, polyacrylamide. 2Q The resulting foam is poured into a mold and curing takes place within 20 minutes.

The proposed foam can also be obtained under industrial conditions. 25 Foam properties are determined by known methods.

The resulting foam is characterized by the following physicomechanical indicators:

Volume weight, kg / m - 28.0 Compressive stress at 10% deformation, MPa0.05

Characteristics of elasticity - compression of 35 specimens without failure,% 75.0 Breathability (P 300 Pa, S 100 mm). Q, m / min 0.055 According to the foam, the composition is suitable for the construction of air-permeable strips in mine conditions.

Example 2. In order to obtain 1 kg of a composition with a content of a 25% aqueous solution of gel-like polyacrylamide in an amount of 15% by weight, the components are weighed in the following quantity, g: 65% aqueous solution of urine-wine-formaldehyde resin 350.0 25% aqueous solution of gel-like polyacrylamide 150, 0 Frother .8.1 Phosphoric acid 22.9

WaterEverything

After a stable foam is obtained, a 65% aqueous solution of a 30% solution is added.

40

45

3

Chevino-formaldehyde resin in the amount of 35 and 15 wt.% gel-type polnakrylamida.

The process for making foam is similar to that described in example t.

The resulting foam has the following properties:

Volumetric weight, kg / m 33 Compressive stress, at 10% deformation, MPa .0.062

Characteristics of elasticity - compression of the sample without damage,% 85 Air permeability (P 300 Pa, S 100 mm) Q, m3 / min 0.030

The foam obtained on the basis of the composition, as compared with that shown in Example 1, is characterized by increased compressive stress and elatichnosti and less breathable. The composition is most suitable for the construction of insulating structures in mines.

Example 3. To prepare one kilogram of the composition with a content of 25% aqueous solution of gel-like polyacrylamide in an amount of 20% by weight, the components are weighed in the following amount, g: 67% aqueous solution of urea-formaldehyde resin 300, 0

25% aqueous solution of gel-like polyacrylamide 200.0 Frother 10.1 Orthophosphoric acid 25.4 Water Remaining Foam preparation process is similar to that described in Example 1.

After foaming of ABO with air, a 67% aqueous solution of urea formaldehyde resin is added in an amount of 30% by weight, premixed with 20% by weight of gel-like polyacrylamide.

The resulting foam has the following properties:

Volumetric weight, kg / m 32 Compressive stress at 10% deformation, MPa0,060 Characteristic of elasticity - compression of the specimen without failure,% 78

098У6

Breathability (P 300 Pa, S 100 mm) Q, m / min0,032

In terms of foam plastic, composition 5 is suitable for erecting breathable strips in mine conditions.

EXAMPLE 4 To prepare 1 kg of a 25% aqueous solution of polyacrylamide in an amount of 5% by weight, the components are weighed in the following quantity, g: 65% aqueous solution of urea-formaldehyde resin 450.0 15 25% aqueous solution

gel polyacrylamide 50, 0 Frother 5.0 Orthophosphoric acid 19.4 20 Water Rest

The technology of foam production is similar to that described in Example 1.:

The resulting foam is characterized by the following physicomechanical indicators:

Volumetric weight, kg / m 26 Compressive stress at 10% deformation, MPa0.039 Characteristic of elasticity - compression of the specimen without fracture,% 73.0 Breathability 35 (p 300 Pa, S 100 mm)

Q, m min0.065

thirty

This composition, due to the high air permeability of the foam and the low compressive stress at 10% deformation, cannot be used to erect insulating structures in mines.

EXAMPLE 5 To prepare 1 kg of a composition with a content of 25% aqueous. Polyacrylamide solution in an amount of 25% by weight, the components are weighed in the following amount, g: 65% aqueous solution of urea formaldehyde resin 250, 0 25% aqueous solution of polyacrylate gel pamid 250.0 Foaming agent 11.0 Phosphoric acid 26.4 Water Remaining.

Ta-: nolog g: cooking penot. gshasta is similar to that described in pri-; .jspe i with

After foaming of the ABO, a 65% aqueous solution of urea-preforming agent is added: 25% of aldehyde resin (,% 5 pre-mixed 11th with 25 mac% of polyacryl gel, etc.

Foam hole;

60 mNo pssuchenny foam has to

blowing properties;

Volumetric vac; kg / k 39 Compressive stress; 1d 10% deformation, Mlla0.037

The characteristic of elasticity - compression obrazd and without destruction - i,% 70 Air permeability (P 300 Pa, S 100 mm) Q, m min 0,050

This composition is not suitable for erecting insulating structures in mines due to increased curing time up to 60 minutes and low value of compressive stress with 10% deformation,

From the foregoing, it follows that the compositions given in examples 1-3 can be used to erect insulating strips in ottoman conditions, the best of which is the composition of example 2.

Claims (2)

COMPOSITION FOR INSULATING FACILITIES IN MINES, including 6067% aqueous solution of urea-formaldehyde resin, foaming agent, hardener and water, characterized in that, in order to increase the strength of structures and reduce their breathability, the composition additionally contains a 25% aqueous solution of gel polyacrylamide, while it contains a triethanolamine salt of lauryl sulfate as a foaming agent, and phosphoric acid as a hardener in the following ratio of components, wt.%: 60-67% aqueous solution of urea-formaldehyde resin Triethanolamine salt of lauryl sulfate Orthophosphoric acid 25% aqueous solution of gel polyacrylamide 10.0-20.0 Water Else 30,0-40,0 0.61-1.01 2.04-2.54>