FR2502161A1 - COMPOSITION FOR THE PREPARATION OF A PLASTIC FOAM - Google Patents

Abstract

The present invention relates to mixtures for the preparation of foam plastics. The mixture for the preparation of foam plastics contains phenol-formaldehyde novolak resin, azoisobutyronitrile, hexamethylenetetramine and a filler. The filler used is a volcanic rock having a particle size of from 5 to 300 mu m, pretreated at a temperature of from 100 to 500 DEG C. The ratio between said components in the mixture is as follows: phenol-formaldehyde novolak resin from 31.0 to 65.5 per cent by weight, azoisobutyronitrile from 1.2 to 5.2 per cent by weight, hexamethylenetetramine from 3.7 to 10.4 per cent by weight, vulcanic rock 19.4 to 64.1 per cent by weight.

Description

 The present invention relates to a composition for the preparation of plastic foams.

 This composition finds an application for the preparation of plastic foams which are widely used as a heat-insulating material in the building industry, in shipbuilding, in refrigeration techniques, etc.

 Plastic foams must have a low density, high thermal protection properties and sufficiently high indices, with regard to mechanical resistance, resistance to fire and heat. In addition, the plastic foams must have a low resin content, that is to say that the consumption of resin (binder) per m3 3 of plastic foam formed must be low.

 The problem of reducing the consumption of the binder and improving the properties of plastic foam, for example, increasing mechanical strength and resistance to fire and heat, with a simultaneous reduction in the price of comes from plastic foam, is a very important problem whose solution allows to widen the possibilities of application of plastic foam.

 One of the ways for the solution of this problem is the use, in compositions for the prepara- tion of plastic foams, of various mineral fillers.

 At the present time, compositions are known for the preparation of plastic foams which comprise artificial porous or mineral powder fillers of different nature.

 In particular, there is known a composition based on phenol-formaldehyde resin of the resol type containing semi-hydrated plaster CaS04.1 / 2 H20 (FRA patent NO 1917012).

 The presence of semi-hydrated plaster in this composition makes it possible to reduce the shrinkage deformations of the plastic foam, as well as to improve to a certain extent its resistance characteristics. The amount of semi-hydrated plaster contained in the composition is within the limits of 10 to 30 Ó by weight.

In order to further increase the resistance of the plastic foam, talc or silicon dioxide is introduced into such a composition (French patent
NO 1410279).

There are also known compositions based on phenol-formaldehyde resin in which, to increase the heat resistance of the plastic foam, inorganic additives are introduced such as B203, Al (OH) 3,
Al203 etc. (USA patent N-3740358).

 We also manage to increase the resistance of a plastic foam to phenol by introducing black or bentonite into the composition for the preparation of the plastic foam (Japanese patents NO 43-27630, 44-9820).

 Compositions based on phenol-formaldehyde resins having high heat resistance and mechanical resistance have been known, in which, as filler, kaolin, kieselguhr, lycopod, wood flour are contained, cork, fibers (French patent NO 40749).

 In other compositions for the preparation of phenol plastic foam, up to 30 tonnes by weight of mineral additives (asbestos, talc, glass powder) are introduced (Finnish patent NO 50131).

 The introduction into the composition of various mineral powder fillers makes it possible, as a general rule, to improve certain properties of the plastic foam, to increase the heat resistance and the mechanical resistance for example, but since the maximum proportion of the charge is not ordinarily greater than 30% by weight, in this case it is not possible to obtain a considerable saving in binder.

 For the preparation of plastic foams for construction and thermal insulation, as well as to reduce the consumption of polymer for their preparation, we have recently started to use fairly widely artificial porous fillers such as keramsite, foam glass, etc.

 We know a composition based on ohenolformaldehyde resin of the resol type and keramsite gravel (Kunstoff im Bau NO 17, 1960) from which is obtained a very high strength plastic foam whose density is 420 kg / m and the compressive strength is 1.2 MPa.

 Another plastic foam with a density of 425 kg / m3 and a limit compressive strength of 1.1 MPa is obtained with the use of granulated foam glass (Kunststoff Rundschau NO 6, 1969).

 There are also known plastic foams obtained by foaming a composition containing a synthetic resin and swollen clay granules. These plastic foams have a density of 386 kg / m3, the limit of the compressive strength is 1.3 MPa and the coefficient of thermal conductivity of 0.3 x 106J / m.

h. degree (0.073 Kcal / m.h. degree) (English patent NO 1217103).

 Plastic foams comprising, as fillers, keramsite gravel, granulated foam glass, etc., given the high density of the fillers which is significantly greater than the density of the foamed polymer (from 2 to 5 times heavier than the plastic foam containing no filler), have lower thermal protection properties. Besides this, the introduction of these fillers, although leading to an increase in the robustness of the plastic foam, does not however make it possible to considerably reduce the consumption of polymer.

 A composition is known for the preparation of a plastic foam composed of phenol-formaldehyde resin, of the novolak type, of azobutyronitrile (porophore), of hexamethylenetetramine (urotropin) and of an artificial porous filler, for example of expanded perlite. .

The plastic foam (gas-filled plastic) obtained by foaming this composition comprises up to 20% by weight of expanded perlite and has high thermal protection properties, sufficiently high resistance characteristics and a high degree of fire resistance. . However, the preparation of such a plastic foam gives rise to a fairly high consumption of resin per 1 m3 (up to 70% by weight).

 Thus, the introduction into the composition of known mineral fillers, both pulverulent and artificial porous in the form of granules, makes it possible to improve certain properties of plastic foams (resistance, thermal stability, etc.), but the use of said fillers does not allow solve the problem of a considerable reduction in the consumption of binder (synthetic resin) and a reduction in the price of plastic foams.

 In the context of the invention, it has been proposed to create a composition for the preparation of plastic foam which would make it possible to obtain a plastic foam having sufficiently high strength properties and a high degree of resistance to heat and to fire, with a reduction in the consumption of binder and a reduction in the amount of plastic foam.

This problem is solved by the fact that in the composition for the preparation of a plastic foam containing a phenol-formaldehyde resin of the novolak type, azoisobutyronitrile, hexamethylenetetramine and a filler, according to the invention, as a charge of volcanic rock whose particle dimensions are between 5 and 300 microns and which is previously heat treated at a temperature between 100 and 5000 C, the ratio of the constituents being as follows, in% by weight
Novolac phenol-formaldehyde resin 31.0 to 65.5 azoisobutyronitrile 1.2 to 5.2 hexamethylenetetramine 3.7 to 10.4 volcanic rock 19.4 to 64.1
The novolak type phenolformaldehyde resin in the composition of the invention serves as a binder. This resin is a condensation product of phenol and formaldehyde in the presence of an oxalic or hydrochloric catalyst. Phenolformaldehyde resin is a linear polymer.

 The content of phenolformaldehyde resin in the composition is within the limits of 31.0 to 65.5 s by weight. This content is determined in each specific case and depends on the one hand on the requirements imposed on the plastic foam, in particular on its density and its robustness, and on the other hand on the properties of the starting resin (viscosity, molecular weight) and the kind of filler chosen.

 When preparing plastic foams whose density reaches up to 120 kg / m3 and the compressive strength is 0.3 MPa, the resin content approaches its maximum value, that is to say say 65.5 x by weight. In the case of the preparation of a plastic foam having relatively low resistance characteristics, it is possible to reduce the amount of resin up to 31.0% by weight.

The foaming of the composition during the preparation of the plastic foam is carried out by introduction into the composition of azoisobutyronitrile, the structural formula of which is as follows

 During the thermal treatment of the composition, during the preparation of the plastic foam, at a temperature between 80 and 1200C the azoisobutyronitrile (gazolyte) decomposes. The gaseous products which are released during its decomposition by passing through the entire composition make it foam. The amount of azoisobutyronitrile which is introduced into the composition depends on the density imposed for the plastic foam, properties of the starting phenolformaldehyde resin and of the composition of the composition; it is within the limits of 1.2 to 5.2 e4 by weight. The optimal amount of azoisobutyronitrile is 2.2 to 3.3% by weight.

 For curing the composition, hexamethylenetetramine (curing agent), the chemical formula of which is (CH2) 6N4, is introduced therein. During the heating of the composition to a temperature of between 140 and 180 ° C., the hexamethylenetetramine decomposes and the products resulting from its decomposition react with the phenolformaldehyde resin, as a result of which the hardening of the latter occurs. . The amount of curing agent is determined by the properties of the starting resin and is within the limits of 3.7 and 10.4% by weight. The optimum amount of filler is 6 to 7.8% by weight.

 As already indicated above, as fillers, volcanic rocks are introduced into the composition for the preparation of the plastic foam.

These natural mineral fillers, the structure of which is porous, exhibit good adhesion to the phenolformaldehyde resin. This is why the introduction into the composition of these fillers whose particle sizes are from 5 to 300 microns makes it possible at the same time to reduce the consumption of resin, to increase the degree of fire resistance and to improve the characteristics. resistance of the plastic foam, since the particles of the charge (volcanic rock) which are placed in the walls of the gas alveoli of the foam mass during the preparation of the plastic foam, reinforce these walls thanks to an adhesive interaction With the resin, the strengthening effect will be greater the greater the specific surface area of the charge, i.e. the particle size of the volcanic rock will be smaller. However, grinding of charges down to particle sizes of less than 5 microns is difficult from a technical point of view and unnecessary. The maximum value of the degree of dispersion of the charge is determined by the average thickness of the wall of the pore (alveolus). To obtain a stable foam structure, it is essential that the particle size of the filler is not greater than the thickness of the wall of the pore, i.e. 300 microns, since in the otherwise, this will cause a change in the gas permeability of the polymer wall and, therefore, destruction of the structure of the foam.

 The most stable foam structure is obtained after the introduction of particles from 20 to 100 microns.

 The amount of dispersed filler contained in the composition depends to a large extent on the nature of the volcanic rock, the properties of the phenolformaldehyde resin and the requirements which the finished plastic foam must meet, and this amount represents from 19.4 to 64, 1% by weight. Reducing the content of the filler composition below the lower limit indicated is not rational from an economic point of view.

The increase in the filler content above the upper limit leads to a decrease in the robustness and to an increase in the density of the plastic foam. The optimum concentration of filler is 34.0 to 40.7% by weight.

 The volcanic rocks whose structure is finely porous are very hygroscopic. The presence of moisture on the surface of the filler particles has a negative influence on their adhesion properties.

 In addition, humidity also contributes to the formation, in plastic foam, of large pores and cavities.

This is why, in order to remove the humidity, the load is subjected beforehand to a heat treatment at a temperature of between 100 and 5000C. The upper temperature limit of the heat treatment is limited by the possibility of swelling of certain particles of volcanic rock. But at the same time, raising the temperature above 1000C considerably reduces the drying time of the load.

 As a volcanic rock in the composition of the invention for the preparation of a plastic foam, it is recommended to use a pearlitic rock, obsidian, pumice, volcanic slag, volcanic ash. All the fillers mentioned above are characterized by a finely porous structure and by fairly good adhesion properties; however, despite the fact that these charges belong to the same group of materials (volcanic rocks), their activity is not the same and that is why the consumption of these charges in the composition and properties of the plastic foam thus obtained are very different and depend on the nature of the load chosen.

 To obtain plastic foams for construction and heat-resistant with high mechanical resistance with a relatively low consumption of resin, it is recommended to add in addition to the composition containing a finely dispersed volcanic rock (5 to 300 microns), a volcanic rock under form of granules whose dimensions are from 3 to 30 mm in an amount up to 700% by weight relative to the weight of the composition, for example volcanic slag or pumice.

The introduction of granules whose dimensions are less than 3 mm causes an increase in the consumption of resin and an increase in the density of the plastic foam, while the use of large granules whose dimensions are greater than 30 mm makes difficult their distribution in the composition and makes the softness of the latter worse. The optimal dimensions of the granules are 10 to 20 mm.

 In order to obtain plastic foams for construction and lighter heat insulators, it is advantageous to introduce in addition, in the composition for the preparation of plastic foam, an artificial porous filler whose granule dimensions are from 3 to 30 mm in an amount up to 480% by weight relative to the weight of the composition.

 As an artificial porous filler, it is recommended to use in the composition for the preparation of plastic foam expanded perlite, keramzite, porous glass.

 The introduction into the composition of volcanic rocks whose particle dimensions are from 5 to 300 microns, despite a large specific surface area of the charge and its large density in the loaded state (800 to 1000 kg / m3), makes it possible to reduce the resin consumption, on average, from 20 to 30% by comparison with the known composition and to prepare light plastic foams whose density is from 40 to 160 kg / m3.

In addition, the plastic foams thus prepared have sufficiently high resistance characteristics (8com = 0.04 to 0.45 MPa) and their coefficient of
com thermal conductivity is low (X = 0.12 to 0.175 x 106J / m. degree hour or 0.028 to 0.042 kcal / m. degree hour).

 Plastic foams with properties of this kind find wide application as a heat-insulating material in various fields of construction.

 The most effective is the use of these plastic foams in light laminated protective structures for walls and roofs in combination with various sheet coating materials, such as aluminum, fiber cement, plastics reinforced with fiberglass, etc.

The use in the composition for the preparation of plastic foam, together with a crushed volcanic rock, artificial porous fillers and volcanic rocks whose granule dimensions are from 3 to 30 mm gives the possibility of preparing plastic foams having high resistance indices = = 0.8 to 1.2 MPa) with relatively low consumption
com low of the resin representing from 50 to 80 kg per 1 m3 of plastic foam.

 The process for preparing the composition for obtaining the plastic foam is simple from the point of view of technological achievement and it is implemented in the following manner.

 A volcanic rock is ground until the particle size is not more than 3 mm using a hammer, jaw crusher, etc. for this purpose. The ground rock is subjected to a heat treatment in a drying drum, or in another drying device, at a temperature between 100 and 5000C until the humidity is not more than 1%. The crushed dried rock is ground in a ball mill, vibrating, etc., until the particle sizes are 5 to 300 microns. Then, all the starting constituents: phenolformaldehyde resin, azoisobutyronitrile, lthexamethylenetetra- mine and crushed volcanic rock are weighed according to the prescribed formula and are introduced into a ball mill or another mixing device to mix them thoroughly.

 In order to prepare a plastic foam, the composition obtained is loaded into molds or else it is introduced into an automatic production line. The dosage of the composition in a mold or on the automatic chain is carried out according to the weight or the volume.

 The quantity of the composition loaded in the mold or on the chain is calculated as a function of the density imposed of the plastic foam and starting from the requirements which this plastic foam must meet with regard to its mechanical strength.

 In the case where, in a composition for the preparation of plastic foam, a volcanic rock or an artificial porous filler is introduced in addition, in the form of granules whose dimensions are from 3 to 30 mm, this charge is mixed with a composition consisting of phenol-formaldehyde resin, azoisobutyronitrile, hexamethylenetetramine and volcanic rock ground directly before admission to the mold or on the chain.

 The composition loaded in the molds or on the automatic chain is subjected to a heat treatment at a temperature between 80 and 1800 C. The heat treatment is carried out in stages. In the first stage, the composition is heated to a temperature between 80 and 1200C. This temperature range corresponds to the melting point of the phenol-formaldehyde resin, to the point of decomposition of the azoisobutyronitrile and foaming of the composition. In the second stage of heat treatment, the temperature is raised to 140 to 1800C.

At this temperature, the phenol-formaldehyde resin interacts with hexamethylenetetramine and passes to the irreversible solid state.

 The duration of the thermal treatment of the composition is determined by the thickness of the plastic foam and by the constitution of the composition. In the preparation of a 50 mm thick plastic foam from a composition consisting of phenolformaldehyde resin, azoisobutyronitrile, hexamethylenetetramine and a ground volcanic rock the duration of the heat treatment is 50 to 90 mins.

 The duration of heat treatment of a composition containing, together with a crushed volcanic rock, a filler in the form of granules of 3 to 30 mm, the thickness of the plastic foam being the same and equal to 50 mm, increases up to 150 minutes away.

 Using an automatic chain, a plastic foam is produced in the form of a continuous canvas of 1200 mm in width and up to 100 mm in thickness.

 At the exit of the channel from the production line, the plastic foam is cut by an automatic plate saw of imposed length.

 In order to better understand the present invention, examples of non-limiting concrete embodiments will be given below.

EXAMPLE 1.

A composition is prepared for the preparation of a plastic foam which is the following, in% by weight: phenol-formaldehyde resin of the novolak type: 65.5 azoisobutyronitrile: 5.2 hexamethylenetetramine: 10.4 perlitic rock: 19.4
The pearlitic rock is ground and dried at a temperature of 1000 C. Then the dried rock is ground in a ball mill until the particle sizes are not more than 300 microns.

 We take 65.5% by weight of phenol-formaldehyde resin, 5.2 and by weight of azoisobutyronitrile, 10.4 ss by weight of hexamethylenetetramine and 19.4 ss by weight of ground pearlitic rock until the dimensions particles are 5 to 300 microns and mixed thoroughly in a ball mill or other suitable mixing device. To obtain the plastic foam, the finished composition is brought from the ball mill to the dosing hopper of an automatic production line in the form of two conveyors arranged one above the other and parallel to each other.

 The composition is dosed on the lower conveyor of the chain according to the volume.

 The height of the layer of the loaded composition is determined by the density of a given plastic foam.

 During the mixing of the composition on the conveyor, it is subjected to heating. The thermal treatment of the composition is carried out at a temperature of between 80 and 180 ° C. When the temperature rises from 80 to 120 ° C., the azoisobutyronitrile decomposes, in this case giving off gaseous products which, by not passing through the molten composition, make this composition foam.

 When the temperature rises to 140 to 1800C, the foamed composition resulting from the interaction of the phenol-formaldehyde resin and the hexamethylenetetramine changes to the irreversible solid state.

 The plastic foam obtained at the exit of the chain is cut into plates of imposed length.

The plastic foam obtained is characterized by the following physical-mechanical indices density, kg / m3: 42 compressive strength limit, (at a deformation of 10%), MPa: 0.12 bending limit, MPa: 0, 26 water absorption, X in volume: 5.4 coefficient of thermal conductivity in the dry state at 25 + 50C, J / m. Hour of degree: 0.117 x 106
EXAMPLE 2.

A composition for plastic foam is prepared which is as follows, in ss by weight phenol-formaldehyde resin of the novolak type: 56.0 azoisobutyronitrile: 2.2 hexamethylenetetramine: 7.8 perlitic rock: 34.0
The heat treatment temperature of pearlite rock is 3009C. The particle sizes of the crushed pearlitic rock are from 5 to 300 microns.

 The process for preparing the composition for obtaining the plastic foam is similar to that described in Example 1.

The plastic foam obtained from this composition is characterized by the following physical-mechanical indices density, kg / m3: 62 compressive strength limit (at a deformation of 10 X), MPa: 0.16 bending limit, MPa: 0.26 water absorption,% by volume: 4.5 coefficient of thermal conductivity in the dry state at 25 + 50C, J / m. Hour of degree: 0.125 x 10
EXAMPLE 3.

A composition is prepared for a plastic foam which is as follows, in S by weight phenol-formaldehyde resin of the novolak type: 50.0 azoisobutyronitrile: 3.3 hexamethylenetetramine: 6.0 perlitic rock: 40.7
The heat treatment temperature of the pearlite rock is 3000 C. The particle sizes of the crushed rock are from 5 to 300 microns
The process for preparing the composition for obtaining the plastic foam is similar to that described in Example 1.

The plastic foam obtained from this composition is characterized by the following physical and mechanical indices density, kg / m3: 48.0 compressive strength limit, (at a deformation of 10 X), MPa: 0.06 flexural limit, MPa: 0.14 water absorption, in% by volume: 5.0 coefficient of thermal conductivity in the dry state at 25 + 50C, J / m. hour. degree: 0.121 x 106
EXAMPLE 4.

A composition is prepared for the preparation of a plastic foam which is the following, in X by weight: phenol-formaldehyde resin of the novolak type: 31.0 azoisobutyronitrile: 1.2 hexamethylenetetramine: 3.7 perlitic rock - 64.1
The heat treatment temperature of pearlite rock is 5000C. The particle sizes of the crushed rock are 20 to 100 microns.

 The process for preparing the composition for obtaining the plastic foam is similar to that described in Example 1.

The plastic foam prepared from this composition is characterized by the following physical-mechanical indices density: kg / m3: 156 limit of compressive strength (at a deformation of 10%), MPa: 0.22 flexural limit, MPa: 0.20 water absorption, in x by volume: 2.4 coefficient of thermal conductivity in the dry state at 25 + 50C, J / m. Hour, degree: 0.176 x 106
EXAMPLE 5.

A composition is prepared for obtaining a plastic foam which is the following, in% by weight phenol-formaldehyde resin of the novolak type: 65.0 azoisobutyronitrile: 1.2 hexamethylenetetramine: 9.1 perlitic rock: 24.7
The heat treatment temperature of pearlite rock is 5000C. The particle sizes of the crushed pearlitic rock are from 20 to 100 microns.

 The process for preparing the composition for obtaining the plastic foam is similar to that described in Example 1.

The plastic foam obtained from this composition is characterized by the following physical-mechanical indices density, kg / m3: 158 limit of resistance to compression (at a deformation of lo%), MPa: 0.43 limit of bending, MPa: 0.56 water absorption, in% by volume: 2.0 coefficient of thermal conductivity in the dry state at 25 + 50C, J / m. Hour, degree: 0.167 x 106
EXAMPLE 6.

A composition is prepared for the preparation of a plastic foam which is the following, in O by weight: phenol-formaldehyde resin of the novolak type: 65.5 azoisobutyronitrile: 5.2 hexamethylenetetramine: 9.1 obsidian: 20.2
The heat treatment temperature of obsidiane is 3000 C. The particle sizes of the crushed obsidiane are from 20 to 100 microns.

 The process for preparing the composition for obtaining the plastic foam is similar to that described in Example 1.

The plastic foam obtained from this composition is characterized by the following physical-mechanical indices density kg / m3: 44 limit of compressive strength (at a deformation of 10%), MPa: 0.12 bending limit, MPa : 0.28 water absorption, in% by volume: 3.3 coefficient of thermal conductivity in the dry state at 25 + 50C, J / m. Hour of degree: 0.117 x 106
EXAMPLE 7.

A composition is prepared for obtaining a plastic foam which is the following, in% by weight: phenol-formaldehyde resin of the novolak type: 56.0 azoisobutyronitrile: 2.8 hexamethylenetetramine: 7.8 obsidian: 33.4
The obsidiane heat treatment temperature is 1000 C. The particle sizes of the crushed obsidiane are from 20 to 100 microns.

 The process for preparing the composition for obtaining the plastic foam is similar to that described in Example 1.

The plastic foam obtained from this composition is characterized by the following physical-mechanical indices density, kg / m3: 61 limit of compressive strength (at a deformation of 10%), MPa: 0.14 flexural limit, MPa: 0.24 water absorption, in% by volume: 2.9 coefficient of thermal conductivity in the dry state at 25 + 5 C, J / m. Hour, degree: 0.125 x 106
EXAMPLE 8.

A composition is prepared for obtaining a plastic foam which is the following, in% by weight phenol-formaldehyde resin of the novolak type: 50.0 azoisobutyronitrile: 3.0 hexamethylenetetramine: 6.0 obsidian: 41.0
The obsidian heat treatment temperature is 1000C. The particle sizes of the crushed obsidlane are 20 to 100 microns.

 The process for preparing the composition for obtaining the plastic foam is similar to that described in Example 1.

The plastic foam obtained from this composition is characterized by the following physical and mechanical indices mass density, kg / m3: 118 limit of compressive strength, (at a deformation of 10%), MPa: 0.29 limit of bending , MPa: 0.43 water absorption, in /. in volume: 2.2 coefficient of thermal conductivity in the dry state at 25 + 50C, J / m. hour, degree: 0.142 x 106
EXAMPLE 9.

A composition is prepared for obtaining a plastic foam which is the following, in% by weight phenol-formaldehyde resin of the novolak type: 31.0 azoisobutyronitrile: 1.2 hexamethylenetetramine: 3.7 obsidian: 64.1
The heat treatment temperature of obsidiane is 5000 C. The dimensions of the particles of crushed obsidiane are from 5 to 300 microns.

 The process for preparing the composition for obtaining the plastic foam is similar to that described in Example 1.

The plastic foam obtained is characterized by the following physical-mechanical indices density, kg / m3: 143 limit of resistance, to compression (at a deformation of 10 d), MPa: 0.16 bending limit, MPa: 0 , 18 water absorption, in X by volume: 2.0 coefficient of thermal conductivity in the dry state at 25 + 5 C, J / m. Hour, degree: 0.159 x 106
EXAMPLE 10.

A composition is prepared for the preparation of a plastic foam which is the following, in% by weight: phenol-formaldehyde resin of the novolak type: 65.0 azoisobutyronitrile: 2.6 hexamethylenetetramine: 10.4 obsidian: 22.0
The obsidian heat treatment temperature is 5000C. The particle size of the crushed obsidian is 5 to 300 microns.

 The process for preparing the composition for obtaining the plastic foam is similar to that described in Example 1.

The plastic foam obtained is characterized by the following physical-mechanical indices density, kg / m3: 132 limit of compressive strength (at a deformation of lo X), MPa: 0.36 bending limit, MPa: 0.54 water absorption, in% by volume: 2.0 coefficient of thermal conductivity in the dry state at 25 + 50C, J / m. hour, degree: 0.155 x 106
EXAMPLE 11.

A composition is prepared for obtaining a plastic foam which is the following, in% by weight phenol-formaldehyde resin of the novolak type: 65.5 azoisobutyronitrile: 5.2 hexamethylenetetramine: 10.4 pumice: 19.4
The pumice heat treatment temperature is 1000C. The particle size of the ground pumice is 5 to 300 microns.

 The process for preparing the composition for obtaining the plastic foam is analogous to that described in Example 1.

The plastic foam prepared is characterized by the following physicochemical indices density, kg / m3: 54 limit of compressive strength (at a deformation of 10 20), MPa: 0.18 bending limit, MPa: O, 10 absorption of water, in t0 by volume: 4.2 coefficient of thermal conductivity in the dry state at 25 + 50C, J / m. hour, degree: 0.125 x 106
EXAMPLE 12.

A composition is prepared for obtaining a plastic foam which is the following, in% by weight phenol-formaldehyde resin of the novolak type: 56.0 azoisobutyronitrile: 4.5 hexamethylenetetramine: 6.1 pumice: 33.4
The pumice heat treatment temperature is 1000C. The particle size of the ground pumice is 5 to 300 microns.

 The process for preparing the composition for obtaining the plastic foam is similar to that described in Example 1.

The plastic foam prepared is characterized by the following physical-mechanical indices density, kg / m3: 108 limit of resistance to compression (at a deformation of 10%), MPa: 0.26 limit of bending, MPa: 0.48 water absorption, in% by volume: 2.8 coefficient of thermal conductivity in the dry state at 25 + 50C, J / m. hour, degree: 0.146 x 106
EXAMPLE 13.

A composition is prepared for obtaining a plastic foam which is the following, in S by weight: phenol-formaldehyde resin of the novolak type: 50.0 azoisobutyronitrile: 2.5 hexamethylenetetramine: 6.5 pumice: 41.0
The pumice heat treatment temperature is 5000C. The particle size of the ground pumice is 5 to 300 microns.

 The process for preparing the composition for obtaining the plastic foam is similar to that described in Example 1.

The plastic foam obtained is characterized by the following physico-mechanical indices: density, kg / m3: 136 limit of compressive strength (at a deformation of 10 nó), MPa: 0.32 bending limit, MPa: 0, 45 water absorption, in% by volume: 2.3 coefficient of thermal conductivity in the dry state at 25 + 50C, J / m. Hour of degree: 0.155 x 106
EXAMPLE 14.

A composition is prepared for obtaining a plastic foam which is the following, in% by weight phenol-f ormaldehyde resin of the novolak type: 31.0 azoisobutyronitrile: 2.5 hexamethylenetetramine: 4.3 pumice: 62.2
The pumice heat treatment temperature is 3000C. The particle size of the ground pumice is 20 to 100 microns.

 The process for preparing the composition for obtaining the plastic foam is similar to that described in Example 1.

The plastic foam obtained is characterized by the following physical-mechanical indices density, kg / m3: 152 flexural limit, MPa: 0.24 compressive strength limit (at a deformation of 10%), MPa: 0.23 water absorption, in% by volume: 2.2 coefficient of thermal conductivity in the dry state at 25 + 50C, J / m. hour, degree: 0.167 x 106
EXAMPLE 15.

A composition is prepared for obtaining a plastic foam which is the following, in% by weight phenol-formaldehyde resin of the novolak type: 65.0 azoisobutyronitrile: 1.9 hexamethylenetetramine: 9.1 pumice: 24.0
The pumice heat treatment temperature is 3000C. The particle size of the ground pumice is 20 to 100 microns.

 The process for preparing the composition for obtaining the plastic foam is similar to that described in Example 1.

 The plastic foam obtained is characterized by the following physical-mechanical indices density, kg / m: 162 limit of compressive strength (at a deformation of 10 X), MPa: 0.45 bending limit, MPa: 0.51 water absorption, in% by volume: 1.8 coefficient of thermal conductivity in the dry state at 25 + 50C, J / m. hour, degree: 0.172 x 106 EXAMPLE 16.

A composition is prepared for obtaining a plastic foam which is the following, in 0 by weight phenol-formaldehyde resin of the novolak type: 65.5 azoisobutyronitrile: 5.2 hexamethylenetetramine: 10.4 volcanic slag: 19.4
The heat treatment temperature of the volcanic slag is 5000 C. The particle sizes of the ground volcanic slag are from 20 to 100 microns.

 The process for preparing the composition for obtaining the plastic foam is similar to that described in Example 1.

 The plastic foam obtained is characterized by the following physico-mechanical indices: density, kg / m3: 74 compressive strength limit (at a deformation of 10 sus), MPa: 0.17 bending limit, MPa: 0, 36 water absorption, in X by volume: 6.5 coefficient of thermal conductivity in the dry state at 25 + 50C, J / m. Hour, degree: 0.134 x 106 EXAMPLE 17.

A composition is prepared for obtaining a plastic foam which is as follows, in X by weight phenol-formaldehyde resin of the novolak type: 56.0 azoisobutyronitrile: 3.3 hexamethylenetetramine: 7.8 volcanic slag: 32.9
The heat treatment temperature of volcanic slag is 5000C. The particle sizes of the ground volcanic slag are from 20 to 100 microns.

 The process for preparing the composition for obtaining the plastic foam is similar to that described in Example 1.

The plastic foam obtained is characterized by the following physical-mechanical indices: density, kg / m3: 98 limit of compressive strength (at a deformation of 10%), MPa: 0.22 bending limit, MPa: 0, 44 water absorption, in X by volume: 5.7 coefficient of thermal conductivity in the dry state at 25 + 50C, J / m. hour, degree: 0.138 x 106
EXAMPLE 18.

A composition is prepared for obtaining a plastic foam which is as follows, in X by weight phenol-formaldehyde resin of the novolak type: 50.0 azoisobutyronitrile: 2.2 hexamethylenetetramine: 7.0 volcanic slag: 40.8
The heat treatment temperature of volcanic slag is 3000C. The particle sizes of the ground volcanic slag are from 20 to 100 microns.

 The process for preparing the composition for obtaining the plastic foam is similar to that described in Example 1.

The plastic foam obtained is characterized by the following physico-mechanical indices, in X by weight density, kg / m3: 122 limit of compressive strength (at a deformation of 10 X), MPa: 0.28 bending limit, MPa: 0.50 water absorption, in% by volume: 4.8 coefficient of thermal conductivity in the dry state at 25 + 50C, J / m. Hour, degree: 0.155 x 106
EXAMPLE 19.

A composition is prepared for obtaining a plastic foam which is as follows, in X by weight phenol-formaldehyde resin of the novolak type: 31.0 azoisobutyronitrile: 2.2 hexamethylenetetramine: 3.7 volcanic slag: 63.1
The heat treatment temperature of volcanic slag is 3000C. The dimensions of the ground volcanic slag are from 5 to 300 microns.

 The process for preparing the composition for obtaining the plastic foam is similar to that described in Example 1.

The plastic foam obtained is characterized by the following physical-mechanical indices density, kg / m3: 148 compressive strength limit (at a deformation of 10 sus), MPa: 0.20 bending limit, MPa: 0.24 water absorption, in Yó by volume: 3.9 coefficient of thermal conductivity in the dry state at 25 + 5 C, J / m. hour, degree: 0.163 x 106
EXAMPLE 20.

A composition is prepared for obtaining a plastic foam which is the following, in% by weight phenol-formaldehyde resin of the novolak type: 65.0 azoisobutyronitrile: 2.6 hexamethylenetetramine: 7.8 volcanic slag: 24.6
The heat treatment temperature of volcanic slag is 1000C. The particle sizes of ground volcanic slag are 5 to 300 microns.

 The process for preparing the composition for obtaining the plastic foam is similar to that described in Example 1.

The plastic foam obtained is characterized by the following physical-mechanical indices density, kg / m3: 156 limit of compressive strength (at a deformation of 10%), MPa: 0.41 bending limit, MPa: 0.62 water absorption, in% by volume: - 3.2 coefficient of thermal conductivity in the dry state at 25 + 50C, J / m. hour, degree: 0.176 x 106
EXAMPLE 21.

A composition is prepared for obtaining a plastic foam which is as follows, in x by weight phenol-formaldehyde resin of the novolak type: 65.5 azoisobutyronitrile: 5.2 hexamethylenetetramine: 10.4 volcanic ash: 19.4
The heat treatment temperature of volcanic ash is 3000C. The particle sizes of the crushed volcanic ash are 5 to 300 microns.

 The process for preparing the composition for obtaining the plastic foam is similar to that described in Example 1.

The plastic foam obtained is characterized by the following physical-mechanical indices density, kg / m3: 87 compressive strength limit (at a deformation of 10 lu), MPa: 0.24 bending limit, MPa: 0.38 water absorption, in ss by volume: 4.1 coefficient of thermal conductivity in the dry state at 25 + 50C, J / m. hour, degree: 0.134 x 106
EXAMPLE 22.

A composition is prepared for obtaining a plastic foam which is the following, in% by weight: phenol-formaldehyde resin of the novolak type: 56.0 azoisobutyronitrile: 2.8 hexamethylenetetramine: 6.1 volcanic ash: 35.1
The heat treatment temperature of volcanic ash is 3000C. The particle sizes of the crushed volcanic ash are 5 to 300 microns.

 The process for preparing the composition for obtaining the plastic foam is similar to that described in Example 1.

The plastic foam obtained is characterized by the following physical-mechanical indices: density, Xg / m3: 46 compressive strength limit, (at a deformation of 10%), MPa: 0.04 bending limit, MPa: 0 , 12 water absorption, in% by volume: 5.6 coefficient of thermal conductivity in the dry state at 25 + 50C, J / m. Hour, degree. 0.121 x 106
EXAMPLE 23.

A composition is prepared for obtaining a plastic foam which is as follows, in% by weight phenol-formaldehyde resin of the novolak type: 50.0 azoisobutyronitrile: 2.8 hexamethylenetetramine: 6.1 volcanic ash: 35.1
The heat treatment temperature of volcanic ash is 5000 C. The particle sizes of the crushed ash are from 20 to 100 microns.

 The process for preparing the composition for obtaining the plastic foam is similar to that described in Example 1.

The plastic foam obtained is characterized by the following physical-mechanical indices density, kg / m3: 102 limit of compressive strength (at a deformation of 10%), MPa: 0.28 bending limit, MPa: 0.43 water absorption, in% by volume: 3.6 coefficient of thermal conductivity in the dry state at 25 + 50C, J / m. hour, degree: 0.18 x 106
EXAMPLE 24.

A composition is prepared for obtaining a plastic foam which is as follows, in eoZ by weight phenol-formaldehyde resin of the novolak type: 31.0 azoisobutyronitrile: 2.5 hexamethylenetetramine:: 4.9 volcanic ash: 61.6
The heat treatment temperature of volcanic ash is 5000C. The particle sizes of the crushed volcanic ash are 20 to 100 microns.

 The process for preparing the composition for obtaining the plastic foam is similar to that described in Example 1.

The plastic foam obtained is characterized by the following physical-mechanical indices density, kg / m3: 153 limit of compressive strength (at a deformation of 10%), MPa: 0.18 bending limit, MPa 0.17 absorption of water,% by volume: 3.0 coefficient of thermal conductivity in the dry state at 25 + 50C, J / m. hour, degree: 0.172 x 106
EXAMPLE 25.

A composition is prepared for obtaining a plastic foam which is as follows, in X by weight phenol-formaldehyde resin of the novolak type: 65.0 azoisobutyronitrile: 3.3 hexamethylenetetramine: 7.8 volcanic ash: 23.9
The heat treatment temperature of volcanic ash is looOC. The particle sizes of the crushed volcanic ash are 20 to 100 microns.

 The process for preparing the composition for obtaining the plastic foam is similar to that described in Example 1.

The plastic foam obtained is characterized by the following physical-mechanical indices density, kg / m3: 160 compressive strength limit (at a deformation of 10 X), MPa: 0.41 bending limit, MPa: 0.69 water absorption, in% by volume: 2.8 coefficient of thermal conductivity in the dry state at 25 + 50C, J / m. hour, degree: 0.176 x 106
EXAMPLE 26.

A composition is prepared for obtaining a plastic foam. For this purpose, we grind a pearlitic rock in a grinder until the particle sizes are not more than 3 mm and we subject the rock to drying at a temperature between 100 and 5000C, We grind the pearlitic rock crushed dry in a ball mill or in another suitable mill up to particle sizes from 5 to 300 microns. Then weigh all the constituents in x by weight phenol-formaldehyde resin of the novolak type: 65.5 azoisobutyronitrile: - 5.2 hexamethylenetetramine: 10.4 crushed perlitic rock with particle sizes from 5 to 300 microns: 19.4
The weighed components are thoroughly mixed in a ball mill or other suitable mixing device.

 For the preparation of the plastic foam, in addition to the finished mixed composition, volcanic slag whose granule dimensions are from 5 to 300 mm and whose density is 702 kg / m3 is introduced. The mixture of the composition with the volcanic slag is produced by one of the known methods.

For 1 m3 of plastic foam, take 100 kg of composition and 700 kg of dry volcanic slag with granule dimensions of 5 to 30 mm, that is to say 700 S of the weight of the composition. After the calculation, the composition of the mixture containing the volcanic slag whose granule dimensions are 5 to 30 mm will be, expressed in% by weight phenol-formaldehyde resin of the novolak type: 8.2 azoisobutyronitrile: 0.6 hexamethylenetetrainine: 1, 3 perlitic rock (crushed): - 2.4 volcanic slag in the form of granules from 5 to 30 mm in size: 87.5
The composition obtained is loaded with the volcanic slag into molds or it is brought to an automatic production line so that the volcanic slag completely fills the volume of the mold or the cavity between the upper and lower conveyors. The composition containing the volcanic slag whose granule dimensions are from 5 to 30 mm, loaded in the molds or on the chain, is subjected to a heat treatment at a temperature between 80 and 1800C.

 During the heat treatment at a temperature of 80 to 1200C, the azoisobutyronitrile decomposes and the products which are released in this case cause the molten composition to foam at this temperature. The foamed composition essentially fills all the gaps between the separate granules of the volcanic slag.

 After the temperature has risen to 140 to 1800 ° C., the foamed composition hardens as a result of the interaction of the phenolformaldehyde resin with hexamethylenetetramine.

 At the end of the automatic production line, the continuous strip of finished plastic foam is cut into separate plates.

The plastic foam prepared has the following physical-mechanical indices density, kg / m3: 800.0 compressive strength limit, MPa 1.28 bending limit, MPa: 1.34 water absorption, in% by volume : 1.8 coefficient of thermal conductivity in the dry state at 25 + 50C, J / m. Hour, degree: 0.527 x 106
EXAMPLE 27.

A composition is prepared for the preparation of the plastic foam which is as follows, in X by weight phenol-formaldehyde resin of the novolak type: 65.5 azoisobutyronitrile: 3.3 hexamethylenetetramine: 7.8 volcanic slag: 23.9
The heat treatment temperature of volcanic slag is 1000C. The particle sizes of ground volcanic slag are 20 to 100 microns.

 700% of the weight of the composition of a volcanic slag is introduced into the composition (per 100 kg), the granule dimensions of which are 5 to 30 mm and the density is 702 kg / m3.

The composition of the composition containing the volcanic slag in the form of granules of 5 to 30 mm is in% by weight phenol-formaldehyde resin of the novolak type: 8.2 azoisobutyronitrile: 0.6 hexamethylenetetramine: 1.3 volcanic slag (ground): 2.4 volcanic slag from 5 to 30 mm in size of granules: 87.5
The methods for preparing the compositions are analogous to the methods described in Example 26. The plastic foam is obtained in the manner described in Example 26.

 The plastic foam obtained has the following physical-mechanical indices density, kg / m3: 800 compressive strength limit, MPa: 1.14 bending limit, MPa: 1.22 water absorption, in% by volume: 3.3 coefficient of thermal conductivity in the dry state at 25 + 50C, J / m. Hour, degree: 0.536 x 106 EXAMPLE 28.

A composition is prepared for the preparation of a plastic foam which is the following, in X by weight: phenol-formaldehyde resin of the novolak type: 50.0 azoisobutyronitrile: 0.6 hexamethylenetetramine: 1.3 pumice: 40.7
The pumice heat treatment temperature is 4000C. The particle size of the ground pumice is 20 to 100 microns.

 In the composition (on 120 kg), an additional 492 X is introduced relative to the weight of the composition of a dry volcanic slag whose granule dimensions are from 10 to 20 mm and the density is 590 kg / m.

The composition with the volcanic slag in the form of granules with dimensions of 10 to 20 mm is the following phenol-formaldehyde resin of the novolak type: 8.5 azoisobutyronitrile: 0.5 hexamethylenetetramine: 1.0 pumice (ground): 6.9 slag volcanic with a granule size of 10 to 20 mm: 83.1
The process for preparing the composition and the plastic foam is similar to that described in text 26.

The plastic foam obtained has the following physical and mechanical indices density, kg / cm3: 710 limit of compressive strength, MPa: 0.98 bending limit, MPa: 1.13 absorption of water in X by volume: 3.9 coefficient of thermal conductivity in the dry state, at 25 + 5 C, J / m. Degree hour: 0.469 x 106
EXAMPLE 29.

A composition is prepared for the preparation of a plastic foam which is the following, in X by weight: phenol-formaldehyde resin of the novolak type: 65.5 azoisobutyronitrile: 5.2 hexamethylenetetramine: 9.1 obsidian: 20.2
The obsidian heat treatment temperature is 3000C.

 The particle sizes of ground obsidian are 20 to 100 microns.

 500% relative to the weight of the composition of a dry pumice, the size of the granules of which is 5 to 30 mm and the density is 500 kg / m, is introduced into the composition (per 100 kg).

The composition containing the pumice whose granule dimensions are from 5 to 30 mm is as follows,
X by weight phenol-formaldehyde resin of the novolak type: 10.9 azoisobutyronitrile: 0.8 hexamethylenetetramine: 1.5 obsidian (ground): 3.4 pumice whose granule size is from 5 to 30 mm: 83.4
The process for preparing the compositions and the plastic foam is analogous to that described in Example 26.

The plastic foam obtained is characterized by the following physical and mechanical indices: density, kg / m3: 600.0 limit of compressive strength, MPa: 1.02 bending limit, MPa: 1.06 water absorption in 9s in volume: 4.2 coefficient of thermal conductivity in the dry state, at 25 + 5OC, J / m. hour, degree: 0.410 x 106
EXAMPLE 30.

A composition is prepared for obtaining a plastic foam containing in weight by weight: phenol-formaldehyde resin of the novolak type: 50.0 azoisobutyronitrile: 3.0 hexamethylenetetramine: 6.0 pumice: 41.0
The pumice processing temperature is 4000C.

 The particle size of the ground pumice is 5 to 300 microns.

 In the composition (over 130 kg), in addition to the dry pumice, the amount represents 246% relative to the weight of the composition and the size of the granules of which is 10 to 20 mm and the density is 320 kg. / m3.

The composition containing the pumice, the size of the granules of which is 10 to 20 mm is as follows, X by weight phenol-formaldehyde resin of the novolak type: 14.4 azoisobutyronitrile: 0.9 hexamethylenetetramine: 1.7 pumice (ground): 11 , 8 pumice whose granule dimensions are from 10 to 20 mm: 71.1
The process for preparing the compositions and the plastic foam is analogous to that described in Example 26.

The plastic foam obtained has the following physical and mechanical indices density, kg / m3: 450 limit of compressive strength, MPa: 0.63 bending limit, MPa: 0.79 water absorption, x by volume: 4.9 coefficient of thermal conductivity when dry at 25 + 50C, J / m. hour, degree: 0.343 x 106
EXAMPLE 31.

A composition is prepared for obtaining a plastic foam containing (% by weight) phenol-formaldehyde resin of the novolak type: 50.0 azoisobutyronitrile: 3.0 hexamethylenetetramine: 6.0 perlitic rock: 41.1
The heat treatment temperature of pearlite rock is 3000C. The particle size of ground pearlitic rock is 20 to 100 microns.

In order to obtain 1 m3 of the plastic foam, an additional 50% is added to the composition (per 100 kg) relative to the weight of the composition of an expanded perlite whose granule dimensions are 3 to 5 mm and the density is 120 kg / m
The process for preparing the compositions and the plastic foam is similar to that described in Example 26.

The composition containing expanded perlite whose granule dimensions are 3 to 5 mm is as follows (by weight) phenol-formaldehyde resin of the novolak type: 31.2 azoisobutyronitrile: 1.9 hexamethylenetetramine: 3.7 perlitic rock (ground) : 25.7 swollen perlite (the dimensions of the granules are 3 to 5 mm): 37.5
The plastic foam obtained is characterized by the following physical and mechanical indices density, kg / m3: 160 compressive strength limit, MPa: 0.48 bending limit, MPa: 0.38 water absorption, 76 by volume : 4.0 coefficient of thermal conductivity in the dry state, at 25 + 50C J / m. Hour, degree 0.159 x 106
EXAMPLE 32.

A composition is prepared for obtaining a plastic foam containing,% by weight: phenol-formaldehyde resin of the novolak type: 50.0 azoisobutyronitrile: 3.0 hexamethylenetetramine: 6.0 obsidian: 41.0
The obsidian treatment temperature is 2000C. The particle sizes of ground obsidian are 20 to 100 microns.

 In order to obtain 1 m3 of the plastic foam, in the composition is added in addition lO X relative to the weight of the composition of an expanded perlite whose granule dimensions are from 3 to 30 mm and the apparent density is 100 kg / m3.

 The process for preparing the compositions and the plastic foam is analogous to that described in Example 26.

The composition containing expanded perlite whose granule dimensions are from 3 to 30 mm is as follows (x by weight) phenol-formaldehyde resin of the novolak type: 45.5 azoisobutyronitrile: 2.7 hexamethylenetetramine: 5.5 obsidian (ground) : 37.3 swollen perlite (the dimensions of the granules are from 3 to 30 mm): 9.0
The plastic foam obtained has the following physical and mechanical indices density, kg / m3: 110 compressive strength limit, MPa: 0.48 bending limit, MPa: 0.38 water absorption, X by volume: 3.4 coefficient of thermal conductivity in the dry state, at 25 + 50C J / m. Hour, degree 0.151 x 106
EXAMPLE 33.

A composition is prepared for obtaining a plastic foam containing, 56 by weight phenol-formaldehyde resin of the novolak type: 50.0 azoisobutyronitrile: 3.0 hexamethylenetetramine: 5.5 volcanic slag: 41.0
The heat treatment temperature of volcanic slag is 3000C. The particle sizes of ground volcanic slag are 20 to 100 microns.

3
In order to obtain 1 m 3 of the plastic foam, an additional 70 X is added to the composition (per 100 kg) relative to the weight of the composition of an expanded perlite whose granule dimensions are from 10 to 20 mm and the bulk density is 76 kg / m.

 The process for preparing the compositions and the plastic foam is analogous to that described in Example 26.

The composition containing expanded perlite whose granule dimensions are from 10 to 20 mm is as follows (x by weight): phenol-formaldehyde resin of the novolak type: 29.4 azoisobutyronitrile: 1.8 hexamethylenetetramine: 3.5 volcanic slag ( ground): 24.1 swollen perlite (the dimensions of the granules are 10 to 20 mm): 41.1
The plastic mass obtained is characterized by the following physical and mechanical indices density, kg / m3: 170 limit of compressive strength, MPa: 0.32 bending limit, MPa: 0.28 water absorption,% by volume : 4.6 coefficient of thermal conductivity in the dry state, at 25 + 50C, J / m. Hour, degree: 0.155 x 106
EXAMPLE 34.

A composition is prepared for obtaining a plastic foam containing (% by weight) phenol-formaldehyde resin of the novolak type: 50.0 azoisobutyronitrile: 3.0 hexamethylenetetramine: 6.0 pumice: 41.0
The pumice processing temperature is 4000C. The particle sizes of the ground pumice are 5 to 300 microns.

3
In order to obtain 1 m of the plastic foam, there is added to the composition (over 120 kg) in addition 480, 'relative to the weight of the composition of a keramsite whose granule dimensions are from 5 to 30 mm and the apparent density is 480 kg / m.

 The process for preparing the compositions and the plastic mass is analogous to that described in Example 26.

The composition containing keramsite whose granule dimensions are from 5 to 30 mm is as follows by weight) phenol-formaldehyde resin of the novolak type: 10.0 azoisobutyronitrile: 0.6 hexamethylenetetramine: 1.2 pumice (ground): 8 , 2 keramsite (whose granule dimensions are from 5 to 30 mm): 80.0
The plastic mass obtained is characterized by the following physical and mechanical indices density, kg / m3: 600.0 compressive strength limit, MPa: 1.36 bending limit, MPa: 1.42 water absorption, X in volume: 3.2 coefficient of thermal conductivity in the dry state, at 25 + 50C, J / m. hour, degree: 0.377 x 106
EXAMPLE 35.

A composition is prepared for obtaining a plastic foam containing (S 6 by weight) phenol-formaldehyde resin: 50.0 azoisobutyronitrile: 3.0 hexamethylenetetramine: 6.0 pearlitic rock: 41.0
The temperature of the heat treatment of pearlitic rock is 5000C. The particle size of the crushed rock is 20 to 200 microns.

 In order to obtain 1 m3 of the plastic foam, an additional 270 X is added to the composition (per 130 kg) relative to the weight of the composition of a keramsite whose granule dimensions are 10 to 20 mm and the mass apparent volume is 350 kg / m.

 The process for preparing the compositions and the plastic mass is analogous to that described in Example 26.

The composition containing keramsite, the granule dimensions of which are 10 to 20 mm, is as follows (by weight) phenol-formaldehyde resin of the novolak type: 13.5 azoisobutyronitrile: 0.8 hexamethylenetetrarnine: 1.6 pearlitic rock (ground): 11.6 keramsite (whose granules are 10 to 20 mm: 72.9
The plastic foam obtained is characterized by the following physical and mechanical indices density, kg / m3: 480 compressive strength limit, MPa: 0.86 bending limit, MPa: 0.79 water absorption,% by volume : 4.6 coefficient of thermal conductivity in the dry state, at 25 + 50C J / m. Hour, degree: 0.293 x 106
EXAMPLE 36.

A composition is precarious for obtaining a plastic foam containing (by weight) phenol-formaldehyde resin of the novolak type: 50.0 azoisobutyronitrile: 3.0 hexamethylenetetramine: 6.0 obsidian: 41.0
The obsidian heat treatment temperature is 3000C. The particle sizes of ground obsidian are 20 to 100 microns.

 In order to obtain 1 m 3 of the plastic foam, 60 s are added to the composition (per 100 kg); relative to the weight of the composition of a plastic material reinforced with fiberglass, the dimensions of the granules of which are 5 to 30 mm and the apparent density is 60 kg / m3.

 The processes for preparing the compositions and the plastic foam are analogous to the processes described in Example 26.

The composition of the composition containing the glass fiber reinforced plastic whose granule dimensions are from 5 to 30 mm is, in% by weight phenol-formaldehyde resin of the novolak type: 3-1.2 azoisobutyronitrile: 1.9 hexamethylenetetramine : 3.8 obsidian (crushed): 25.6 glass fiber reinforced plastic with granule dimensions of 5 to 30 mm: 37.5
The plastic foam obtained has the following physical-mechanical indices density, kg / m3: 160 limit of resistance to compression, MPa: 0.42 limit of bending, MPa: 0.36 absorption of water, in X in volume: 4.8 coefficient of thermal conductivity in the dry state at 25 + 5QC, J / m. hour, degree: 0.146 x 106
EXAMPLE 37.

A composition is prepared for the preparation of a plastic foam having the following composition, in
X by weight phenol-formaldehyde resin of the novolak type: 50.0 azoisobutyronitrile: 3.0 hexamethylenetetramine: 6.0 obsidian: 41.0
The obsidian heat treatment temperature is 3000C. The particle sizes of the obsidian are 20 to 100 microns.

 To obtain 1 m3 of the plastic foam, 30 X is added in the composition (per 100 kg) relative to the weight of the foam glass composition with particle sizes of lo to 20 mm and apparent density of 30 kg / m.

 The process for preparing the composition of the plastic foam is similar to that of Example 26.

The composition of the formulation with foam glass with particle sizes from 10 to 20 mm is as follows (in X by weight) phenol-formaldehyde resin of the novolak type: 38.5 azoisobutyronitrile: 2.3 hexamethylenetetramine: 4.6 obsidian ( crushed): 31.5 foam glass (10 to 20 mm): 23.1
The plastic foam obtained has the following physicomechanical indices mass in volume, kg / m: 130 limit of resistance to compression, MPa: 0.38 limit of resistance to bending, MPa: 0.59 absorption of water, in volume: 5.6 coefficient of thermal conductivity in the dry state, at 25 + 50C, J / m. Hour, degree: 0.142 x 106
Since the properties of the phenolformaldehyde resins used in the composition vary within wide limits, the physical-mechanical indices of the plastic foams obtained from it can also vary within limits of 20 to 40 X.

Claims (5)

 1. Composition for the preparation of plastic foams containing a phenol-formaldehyde resin of the novolak type, azoisobutyronitrile, hexamethylenetetramine and a filler, characterized in that it contains, as a filler, a volcanic rock having particle sizes of 5 to 300 microns which has been subjected beforehand to a heat treatment at a temperature of 100 to 5000 ° C., the ratio of the constituents being as follows, in X by weight phenol-formaldehyde resin of novolak type: 31, 0 to 65.5 azoisobutyronitrile: 1.2 to 5.2 hexamethylenetetramine: 3.7 to 10.4 volcanic rock: 19.4 to 64.1  2.Composition according to claim 1, characterized in that one uses, as volcanic rock, a pearlitic rock, obsidian, nonce, a volcanic slag or volcanic ash.  3. Composition according to claim 1 or 2, characterized in that it additionally contains a volcanic rock in the form of granules whose dimensions are from 5 to 30 mm, at a rate of up to 700 X by weight relative to the weight of the composition.  4. Composition according to claim 1, characterized in that it also contains a synthetic porous filler in the form of granules from 3 to 30 mm, in an amount of up to 480% of the weight of the composition.  5. Composition according to claim 4, characterized in that one uses, as synthetic porous filler, expanded perlite, keramsite or foam glass.