RU2344109C1 - Fireproof porous heat and sound insulating material and production method - Google Patents

Abstract

FIELD: construction.

SUBSTANCE: invention relates to production methods of the light porous fireproof heat and sound insulating materials to be used in construction, shipbuilding, aviation and power production industries, in cryogenic technologies and other industries. The fireproof porous heat and sound insulating material is produced from raw mixture including, wt %: fibrous material 2.5-2.8; fine inorganic filling material 0.3; penetrating agent SV-102 0.5; water repellent and binding component GKZh-94 0.4; liquid dispersion medium - water 96.3-96.7. Asbestos or asbestos with silica fiber or basalt fiber or carbon fiber at their ratio 1:1, or basalt fiber and polyaramide fiber dispersed so that fiber diameter is no more than 0.01 mcm and fiber length is less than 2 mm. Graphite or wollastonite or mica in the shape of less than 5 mcm-sized flakes is used as fine filling agent. The invention describes the production method of fireproof porous heat and sound insulating materials from the aforesaid raw mixture.

EFFECT: improvement of heat-transfer and sound-insulating properties of heat and sound insulating material (especially, under high temperatures) and fireproofing of structures based on use of this material.

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Description

The present invention relates to the field of producing lightweight porous fire-resistant heat and sound insulating materials based on fibrous materials that will find application in construction, shipbuilding, aviation and energy industries, in cryogenic engineering and other industries.

Sound-proofing and heat-insulating materials and raw mixes for their manufacture on the basis of foamed dispersions are known, which include fluffy fibrous asbestos, including in combination with various fillers - USSR copyright certificate No. 724485 and Russian patent No. 2001897 (1, 2). The material obtained according to these inventions has a sufficiently large bulk density (80-100 kg / m ³ ), which is necessary in order to have satisfactory thermophysical characteristics (thermal conductivity at 500 ° C = 0.045 W / m · K). In addition, these materials are not fire resistant (maximum operating temperature does not exceed 600 ° C).

At the same time, the proposed material has significantly better thermophysical characteristics with a significantly lower bulk density (not more than 50 kg / m ³ ) and, most importantly, can withstand prolonged heating up to 1000 ° C and can be used in fire-resistant structures.

Closest to the proposed heat and sound insulating material is a material manufactured according to UK patent No. 1131044 (3).

The material based on dispersed asbestos, obtained according to the patent prototype, has good thermal insulation properties under ordinary conditions (thermal conductivity 0.04 W / m · K at 20 ° C). However, with a significant increase in temperature, the thermal insulation properties of this material significantly deteriorate (reaching 0.6 W / m · K at 500 ° C). With an even greater increase in temperature (above 700 ° C), chemical asbestos dehydration occurs - the destruction of crystalline hydrates, and thermal insulation completely loses its mechanical strength.

Thus, according to the prototype patent, a material is made that does not have fire retardant properties (maximum operating temperature is not more than 700-750 ° C) and, in addition, at temperatures above 150 ° C it has unsatisfactory thermal characteristics. This does not allow its use as thermal protection in fire fighting structures.

The objective of the invention is to improve the thermophysical and sound insulating characteristics of the heat and sound insulating material (especially at elevated temperatures), as well as giving the structures based on it fire-resistant properties (the ability to withstand flame for a long time in case of fire) due to the formation of a porous structure mainly with a closed type of pore.

This is achieved by the fact that the fire-resistant porous heat and sound insulating material is prepared from a raw material mixture comprising the following components:

- fibrous material;

- finely ground inorganic filler;

- surface-active substance;

- hydrophobizing and binding component;

- liquid dispersion medium.

The ratio of closed and open pores in the structure of the material is not less than 3: 1, and the weighted average fractions of closed and open pores in the structure of the material are 54-72%, and 10-18% of their total number, respectively.

The material is characterized in that natural or man-made mineral fibers (as well as their mixtures) are used as the fibrous component of the raw material mixture, dispersed to the following parameters: fiber diameter not more than 0.01 μm, their length less than 2 mm.

The material is also characterized in that flake particles are made from an inorganic filler.

It is proposed to use natural or technogenic mineral fibers (as well as mixtures thereof) from the series: asbestos, basalt, glass or carbon fiber, various types of polymerized fibers (polyaramide, polyester) as a fibrous material. Being the skeleton base of the heat-insulating material, the fibrous components of the raw material mixture must be dispersed to the following parameters: fiber diameter of not more than 0.01 μm, their length less than 2 mm.

The dispersion of the fibers to the indicated sizes is necessary to ensure conditions under which the structure of the skeleton of the material will consist mainly of closed pores. With larger fibers, it is impossible to ensure the predominance of closed pores, which significantly impairs the sound and thermal properties of insulation.

The filler can be used from a number of: graphite, mica, vermiculite, wollastonite, metal oxides (aluminum, titanium and others). A prerequisite for using the substance as a filler in accordance with this invention is the possibility of imparting a scaly shape to its crushed particles.

This choice of the shape of the filler particles is due to the fact that only scaly particles can (due to the difference in surface electric and chemical potentials) envelop the structure-forming fibers to the greatest extent and, thus, shield them from thermal radiation when exposed to a fire flame (due to the possibility of turning the flakes around the axis fibers in a liquid dispersion medium containing surfactants in combination with polyorganosiloxane), while contributing to the closure of pores.

Examples of flame retardant material are given below.

Example 1

967 g (96.7% of water), 25 g (2.5%) of inorganic fiber (asbestos), 3 g (0.3%) of inorganic filler — graphite of grade C-1 with a flake size of less than 5 microns are placed in the working chamber of the apparatus , 5 g (0.5%) of a surfactant is sodium bis (2-ethylhexyl) succinate sulfonate (wetting agent SV-102).

As a result of dispersion of the inorganic fiber and foaming of the dispersion, followed by termination, a fire-resistant porous heat and sound insulating material with a ratio of closed and open pores of 5.4: 1 is obtained, and the weighted average fractions of closed and open pores in the material structure are 54 and 10%, respectively.

Example 2

963 g (96.3% water), 25 g (2.5%) of the mixture in an equal ratio of 1: 1 inorganic fibers - silica and asbestos, 3 g (0.3%) inorganic filler - graphite grade are placed in the working chamber of the apparatus C-1 flake size less than 3 microns; 5 g (0.5%) of wetting agent SV-102 and 4 g (0.4%) of polyorganosiloxane (GKZh-94).

As a result of dispersion of the inorganic fiber and foaming of the dispersion, followed by termination, a fire-resistant porous heat and sound insulation material with a ratio of closed and open pores of 4: 1 is obtained, and the weighted average fractions of closed and open pores in the structure of the material are 72 and 18%, respectively.

Example 3

963 g (96.3% water), 25 g (2.5%) of the mixture in an equal ratio of 1: 1 inorganic asbestos and wollastanite fibers, 3 g (0.3%) carbon fiber with a fiber diameter of less than 0 are placed in the working chamber of the apparatus , 01 μm; 5 g (0.5%) of wetting agent SV-102 and 4 g (0.4%) of polyorganosiloxane (GKZh-94).

As a result of dispersion of the inorganic fiber and foaming of the dispersion, followed by termination, a fire-resistant porous heat and sound insulation material with a ratio of closed and open pores of 7.2: 1 is obtained, and the weighted average fractions of closed and open pores in the material structure are 72 and 10%, respectively.

Example 4

963 g (96.3% water), 25 g (2.5%) basalt fiber, 3 g (0.3%) polyaramide fiber with a fiber diameter of less than 0.01 μm are placed in the working chamber of the apparatus; 5 g (0.5%) of wetting agent SV-102 and 4 g (0.4%) of polyorganosiloxane (GKZh-94).

As a result of dispersion of the inorganic fiber and foaming of the dispersion, followed by termination, a fire-resistant porous heat and sound insulating material with a ratio of closed and open pores of 3: 1 is obtained, and the weighted average fractions of closed and open pores in the material structure are 54 and 18%, respectively.

Example 5

963 g (96.3% water), 25 g (2.5%) of the mixture in an equal ratio of 1: 1 fibers (fiberglass and asbestos), 3 g (0.3%) of mica with a flake size of less than 5 are placed in the working chamber of the apparatus microns; 5 g (0.5%) of wetting agent SV-102 and 4 g (0.4%) of polyorganosiloxane (GKZh-94).

As a result of dispersion of the inorganic fiber and foaming of the dispersion, followed by termination, a fire-resistant porous heat and sound insulation material with a ratio of closed and open pores of 4.5: 1 is obtained, and the weighted average fractions of closed and open pores in the material structure are 63 and 14%, respectively.

A method of obtaining a flame retardant material is known from the same source 3.

A method of obtaining a flame retardant porous heat and sound insulating material includes:

- dispersing the components in a liquid dispersion medium;

- Porization of the resulting dispersion;

- removal of fluid;

- thermal curing.

However, the prototype method has the same limitations as described above.

The objective of the invention is to obtain optimal dispersion parameters of inorganic fibers and a given porous structure of the final material, and the technical result is to increase the fire resistance of the material.

For this, the porization of an aqueous suspension containing components of the raw material mixture is carried out under the influence of air pulsations with a frequency of 260-420 kHz.

During mechanical action in the process of dispersion and porization of an aqueous suspension containing components of the raw material mixture, it is turbulized and the processed gas-liquid medium is crushed in the volume of the foam generator. High-frequency air pulsations (with a frequency of 260-420 kHz) applied to the mixed medium provide effective splitting of the fibers in diameter without chopping them in length (this phenomenon contributes to obtaining a strong and light heat and sound insulating material), as well as uniform adsorption of fillers and water-repellent and binder components on the surface of the fibers, which ultimately gives stability to the properties of thermal insulation.

In the process of dispersion and foaming under the influence of physical and mechanical factors, including pulsating effects, the adsorption of particles on the fibers, their binding to polyhydrosiloxanes, the initial formation of the ordered structure of the fire-resistant material occurs. The total duration of bubble pulsations during mechanical dispersion and foaming of the raw material mass ranges from 4-5 minutes. Over such a period of time, a uniform structure of material cells is formed in the form of cavities with film partitions, and mainly closed pores are formed, which are necessary to impart fire-resistant properties to the material, as well as improve its thermophysical and soundproofing characteristics (the optimal ratio of closed and open pores is not less than 3: 1 respectively).

After preparing the foamed mass and pouring it into molds (it is also possible to apply foam on an object or surface), the resulting material structure is finally fixed with a gradual increase in temperature from 70 to 300 ° C for 5-7 hours.

The manufactured heat and sound insulating material, consisting mainly of closed porous cells, is fireproof, non-combustible, resistant to mechanical and chemical influences, environmentally friendly, and also has a maximum operating temperature of 1000 ° C and a thermal conductivity of 0.029-0.036 W / m · K. Due to the properties obtained, the material is able to keep the spread of flame and heat fluxes in fire fighting structures.

Examples of a method for producing a flame retardant material are given below.

Example 1

967 g (96.7% of water), 25 g (2.5%) of inorganic fiber (asbestos), 3 g (0.3%) of inorganic filler — graphite of grade C-1 with a flake size of less than 5 microns are placed in the working chamber of the apparatus , 5 g (0.5%) of a surfactant is sodium bis (2-ethylhexyl) succinate sulfonate (wetting agent SV-102).

The components are dispersed in a liquid dispersion medium, the resulting dispersion is porous by foaming, then the liquid is removed from the foam and thermal curing is carried out, but the aqueous suspension containing the components of the raw material mixture is porous by exposure to air pulsations with a frequency of 260 kHz.

Example 2

963 g (96.3% water), 25 g (2.5%) of the mixture in an equal ratio of 1: 1 inorganic fibers - silica and asbestos, 3 g (0.3%) inorganic filler - graphite grade are placed in the working chamber of the apparatus C-1 flake size less than 3 microns; 5 g (0.5%) of wetting agent SV-102 and 4 g (0.4%) of polyorganosiloxane (GKZh-94).

The components are dispersed in a liquid dispersion medium, the resulting dispersion is porous by foaming, then the liquid is removed from the foam and thermal curing is performed, but the aqueous suspension containing the components of the raw material mixture is porous by exposure to air pulsations with a frequency of 340 kHz.

Example 3

963 g (96.3% water), 25 g (2.5%) of the mixture in an equal ratio of 1: 1 inorganic asbestos and wollastanite fibers, 3 g (0.3%) carbon fiber with a fiber diameter of less than 0 are placed in the working chamber of the apparatus , 01 μm; 5 g (0.5%) of wetting agent SV-102 and 4 g (0.4%) of polyorganosiloxane (GKZh-94).

The components are dispersed in a liquid dispersion medium, the resulting dispersion is porous by foaming, then the liquid is removed from the foam and thermal curing is carried out, but the aqueous suspension containing the components of the raw material mixture is porous by exposure to air pulsations with a frequency of 420 kHz.

Example 4

963 g (96.3% water), 25 g (2.5%) basalt fiber, 3 g (0.3%) polyaramide fiber with a fiber diameter of less than 0.01 μm are placed in the working chamber of the apparatus; 5 g (0.5%) of wetting agent SV-102 and 4 g (0.4%) of polyorganosiloxane (GKZh-94).

The components are dispersed in a liquid dispersion medium, the resulting dispersion is porous by foaming, then the liquid is removed from the foam and thermal curing is performed, but the aqueous suspension containing the components of the raw material mixture is porous by exposure to air pulsations with a frequency of 300 kHz.

Example 5

963 g (96.3% water), 25 g (2.5%) of the mixture in an equal ratio of 1: 1 fibers (fiberglass and asbestos), 3 g (0.3%) of mica with a flake size of less than 5 are placed in the working chamber of the apparatus microns; 5 g (0.5%) of wetting agent SV-102 and 4 g (0.4%) of polyorganosiloxane (GKZh-94).

The components are dispersed in a liquid dispersion medium, the resulting dispersion is porous by foaming, then the liquid is removed from the foam and thermal curing is performed, but the aqueous suspension containing the components of the raw material mixture is porous by exposure to air pulsations with a frequency of 380 kHz.

Information sources

1. USSR author's certificate No. 724485, С04В 43/04, 1980.

2. Patent of Russia №2001897, С04В 38/10, 1993.

3. British patent No. 1131044, C04B 43/04, 1968.

Claims (2)

1. Fire-resistant porous heat and sound insulation material made from a raw material mixture containing fibrous material, a finely ground inorganic filler, a surfactant, a hydrophobic and binder component, a liquid dispersion medium, characterized in that the raw material mixture contains asbestos or asbestos as a fibrous material silica fiber, or basalt fiber, or carbon fiber at a ratio of 1: 1, or basalt fiber and polyaramide fiber dispersed until olokon with a diameter of not more than 0.01 μm and a length of less than 2 mm, graphite or wollastonite, or mica in the form of flakes with a particle size of less than 5 μm, as a surfactant, a wetting agent SV-102, as a water repellent and binder - GKZH-94, as a liquid dispersion medium - water, with the following ratio of components, wt.%:
Specified fibrous material 2.5-2.8 Specified finely ground inorganic filler 0.3 Weter SV-102 0.5 GKZH-94 0.4 Water 96.3-96.7
the resulting material is characterized by a ratio of closed and open pores of at least 3: 1, and the weighted average fractions of closed and open pores in the structure of the material are 54-72%, and 10-18% of their total number, respectively. 2. A method of obtaining a flame-retardant porous heat and sound insulating material from a mixture according to claim 1, including dispersing the components in an aqueous dispersion medium, porizing the resulting dispersion, removing liquid, thermal curing, characterized in that the porosity of the aqueous suspension is carried out under the influence of air pulsations with a frequency of 260-420 kHz