RU2744369C1 - Device for manufacture of blocks of foamed polymeric materials (options) and method of manufacturing such blocks - Google Patents

Abstract

FIELD: polymers.

SUBSTANCE: invention relates to the field of production of block elements made of foamed polymer. The device for the manufacture of blocks of foamed polymeric materials contains a mold with a bottom and side walls that form a volume for accommodating a foamable polymeric material loaded from above for foaming during polymerization. Along each side wall of the mold is placed a sheet material made with low adhesion to the expandable polymeric material to form a separating layer. In this case, the thin-sheet material brought out in the upper part of the mold is connected to a shaft having a drive for its rotation for lifting along the wall of this thin-sheet material along the volume in which the polymer material is foaming, and ensuring the relative movement of the separating layer relative to the specified volume.

EFFECT: improved quality of the structure of the obtained foam blocks.

8 cl, 3 dwg

Description

The invention relates to the field of production of block elements made of foamed polymer, in particular polyurethane foam blocks, and concerns the design of devices that ensure the production of such block elements, and the method of their production in the mode of intermittent production of blocks in stationary forms (using the "foaming in boxes" method), which allows facilitate and simplify the production of homogeneous foam blocks having a substantially uniform shape with uniform compressive strength in the edge regions.

Various methods and corresponding shapes are known in the art that attempt to achieve the desired fixed shape characteristics with little waste, structural uniformity and uniformity, inter alia, ultimate strength.

Currently, in the production of foamed polymer materials, two technologies are usually used: continuous production and production of individual blocks.

In continuous production, foaming takes place on a special production line, limited on four sides. The change in the volume of the polymer occurs gradually when it moves forward or upward and with limited movable walls. To ensure normal operation, a separating film moves between the movable wall and the polymer, which has a low surface activity and does not adhere to the polymer. Blocks are cut continuously at the end of the line. The advantage of the method is the guaranteed convenient shape of the section, which makes it possible to minimize waste during further production, as well as the ability to change the length of the blocks during cutting. However, this method justifies the costs only for mass production, since the equipment has significant longitudinal (vertical) dimensions, as well as significant deviation from the shape when starting and stopping the line (initial and final sections), which are waste.

Thus, WO 2009095230 describes a container-type apparatus for block-type foam production and a method for block-type foam production. The specified device contains a horizontally located base for receiving the expandable foaming reaction mixture and at least one vertically located side wall, the surface of which is in contact with the expanding foam and is movable in the vertical direction. The specified side wall contains a flexible surface element that can pass between the rotating rollers, forming a conveyor. This container can be used, in particular, for the production of a polyurethane foam block according to the "foaming in boxes" method. The side wall additionally contains bumps on the surface in contact with the foam for cleaning the foam after the end of the cycle.

DE 1504091 describes a device which prevents the formation of a curved dome-shaped surface in the longitudinal direction of the block. The device essentially consists of a tunnel through which the reaction foam is passed. The tunnel is closed at one end by an insert through which the premixed reaction mixture is fed in a suitable continuous mode. In a preferred embodiment of the present invention, an apparatus is used for the production of polyester or polyetherurethane foam blocks having a vertically disposed tunnel into which the reaction mixture is introduced from below so that the resulting foam is discharged upward. The inner walls of the tunnel are provided with continuously moving paper webs or protective films that are wound on rollers. An endless conveyor belt is located between the paper webs and the wall of the tunnel, the rotation speed of which is adjustable.

US 4,567,008 describes a continuous foam production process in which the expanding materials are fed from the bottom at a controlled rate and the foam is discharged from the top at an appropriate rate. Foaming occurs in an expanding chamber bounded by a moving sheet material, limited to follow the diverging path so as to travel with the expanding material at a speed corresponding to its travel speed. In the expansion chamber (casing), moving surfaces in the form of polyethylene belts are provided on the walls, which are fed from the rolls and pulled around the lower edges of the end walls by means of conveyors. The canvases remain at the ends of the resulting foam blocks. The movable surfaces for the curved side walls of the expansion casing are provided with paper webs, which are fed from the rolls and pulled through the machine by means of driven pressure rolls to the take-up rolls, separating them from the side of the block face. The paper webs pass through the machine once and are disposed of after use. Rail conveyors and pinch rollers are synchronized by a common drive consisting of four shafts in a square formation with pairs of bevel gears at the corners.

GB 1210513 describes a method for producing a foamed plastic product by introducing material into a chamber formed by downwardly moving conveyors; the length and speed of the conveyors are such that the material is contained until it foams and compresses. As shown, the foam is fed into a chamber bounded by endless belts. The film covers the belts and becomes inseparably bound to the foam. The foamed resin can be polyurethane or a condensation product of formaldehyde and phenol or an amine such as urea, thiourea, guanidine or melamine, and is preferably cured after it leaves the molding chamber. The facing sheet may contain flexible material such as films of polyethylene, polypropylene, polyethylene terephthalate, polystyrene, vinyl chloride, paper, plastic-coated paper or metal foil, or they may contain rigid sheet material such as plywood, asbestos sheets, drywall, metal or plastic material in thick sheets.

The listed devices are based on the fact that moving films or belts are stretched along the walls of the tunnel or chamber, which move along the walls of this tunnel for a time sufficient to complete the process of foaming of the polymer material. After that, the film is separated from the foam block. And the foaming process begins after the original polymer material is fed from the bottom into the tunnel. In these known solutions, the use of moving films or belts or conveyor belts is used exclusively to hold the expanding material in the volume of the boundaries of the side walls and move it up (to the position of extraction from the tunnel / chamber) due to the fact that between the material of the belts or films or the conveyor belt and the material of the polymer mass is adhesion. This is the only thing that allows the films or tapes (moving continuously along the walls of the tunnel or chamber) to lift the foaming block from the feed zone at the bottom of the tunnel to its top to the position of unloading the finished foam block.

This technology is suitable for the production of long blocks, which are subsequently cut into plates. Naturally, with this technology, swelling (“dome” or “loaf” effect) occurs only on the front of the long block. This part is cut off and disposed of. Such devices and the methods for the manufacture of foam blocks used on them are suitable exclusively for factory conditions in the industrial mass production of products.

However, there is a rather big need for the production of small-scale or narrow batches of foamed blocks, which are not economically justified to produce at a mass-production plant, in this case the "foaming in boxes" method or the so-called block production is used.

In block production, foaming occurs in a special volume, open or closed on one side with a movable cover. The walls bounding the volume are also separated from the polymer by a film with low surface activity, or coated with a composition with low adhesion to the polymer. The main advantage of the method is the small overall dimensions of the equipment, as well as the ability to produce blocks in small quantities. The main disadvantage is the appearance of a large amount of waste and an inhomogeneous structure of cells in the volume of the block. Inhomogeneity and shape deviation arise due to the action of surface tension forces at the interface between the separating film (or coating) and the polymer when the volume of the latter changes.

Known devices US 4988271, US 4014967 (in the form of a box) for the manufacture of blocks of foamed polymeric materials, which is a volume for foaming the material during polymerization, limited by the bottom, side walls having an internal insert made to slide along the inner surface of the walls and a lid (US 4014967), rising at a certain speed by a given amount, providing the required density.

US Pat. No. 4,988,271 discloses a batch-type foaming device for the production of a polyurethane foam block, comprising a mold comprising a flat bottom, sides perpendicular to the bottom, an open top, a lifting clamp open at opposite ends, and a jig having a wall movable along the inner surfaces of the side walls of the specified shape, a plurality of shafts horizontally located synchronously rotating at equal speed, and lifting cables connected at one end with the upper end of the specified clamping device, and at the other end with the shafts, with the possibility of rotation for winding the cable when pouring and foaming a foamable polyurethane reaction mixture in the specified mold for synchronous lifting of the specified clamp with the rise of the level of the upper surface; the specified reaction mixture and ultrasonic sensor means. The sensor means is connected to the clip for determining the distance between the sensor means and the level of the surface of the said reaction mixture to control the drive. When the distance between the sensor means and the rising surface of the reaction mixture is within a predetermined value, lifting the clamp in synchronization with the rate of rise of the reaction mixture.

US 4014967 (B29D 27/04, publ. 03/29/1977) describes a device for the production of foam parts in an open form, having an internal sheet metal insert and a movable cover associated with it, said insert adapted to slide along the inner surface of the walls, when expanding the expandable reaction mixture. As the reaction mixture expands, the foam freely expands upwardly during the first stage of the process to at least about 50% of the desired height. At this point, the expanding foam engages with the inwardly projecting part of the flange of the movable insert on which the movable floating cover is mounted. Once engaged with the flange portion, the foam continues to expand and the movable insert and installed movable floating cover move upward to the desired final foaming height, thereby forming a homogeneous foamed plastic piece having substantially uniform properties throughout.

This decision was made as a prototype for the declared objects.

During polymerization during foaming, the lower layers of the polymer material faster than other layers (due to contact with the walls, which have a temperature lower than the temperature of the polymer material poured into the mold), acquire a stable foamed form with a closed-cell structure (provided due to the temperature difference). In this regard, it is this part of the future foamed block that practically does not stick into the adhesive interaction with the walls of the mold. The foaming part, which rises to the top, has a polymerization that is non-uniform in time over the area in the plan of the block shape. The edge areas in contact with the side walls of the mold polymerize faster than the middle (central) part of the block. This leads to the formation of a “dome” (“loaf”) effect, since in the central zone the temperature of the polymer mass is higher than at the edges at the walls.

To eliminate this phenomenon (the “dome” (“loaf”) effect), the known solution uses a glass-shaped lid, which is placed on top of the poured polymer mass. This lid has a side wall height less than the mold side wall height; its side wall contacts or slides along the inner surface of the mold side walls. As the polymer mass foams and the volume increases, the lid rises along the walls of the mold, preventing the formation of a dome.

The disadvantage of this known solution lies in the fact that the lid has a weight, and after placing it on the polymer mass, this lid regulates the density of the foaming by its weight. At the same time, this cover restricts the freedom of lifting of the foaming mass, which leads to its compaction at the walls of the mold and at the walls of the cover. After polymerization, there is a problem with the removal of this cover, given that the material of the polymer mass adheres to the material of the cover. And when using a lid material with low adhesion to the polymeric material, after removing the lid, the side walls of the foam block have a stepped shape, which must be corrected by cutting off the protruding parts. Such manufacturing leads to a rather large overspending of the polymer material. In this case, the resulting block can have a non-uniform structure.

In addition, during polymerization (foaming), an increased pressure is formed on the walls of the block (during foaming, a pressure of 0.3-0.5 MPa develops), leading to an increase in the thickness of the block. With a limited volume, this pressure begins to build up and some of the material can be extruded into the gaps between the walls of the lid and the mold. This leads to deceleration of the cover, which affects the density of the block and creates heterogeneity in the structure.

The present invention is aimed at achieving a technical result consisting in reducing the adhesion between the walls of the device mold and the polymer material to improve the quality of the structure of the resulting foam blocks.

The specified technical result is achieved by the fact that in the device for the manufacture of blocks of foamed polymeric materials, containing a mold with a bottom and side walls, forming a volume for placing a foamable polymeric material loaded from above for foaming during polymerization, forming a volume for accommodating a foaming polymeric material for foaming in the process of polymerization, along each side wall of the mold, a thin sheet material is placed, made with low adhesion to the expandable polymer material to form a separating layer, while the thin sheet material brought out in the upper part of the mold is connected to a shaft that has a drive for its rotation for lifting along the wall of this thin sheet material along the volume in which the polymeric material is foaming, and ensuring the relative movement of the separating layer relative to the specified volume.

For this embodiment, the sheet material can be made of plastic film or paper. The sheet material can be stretched along the wall to the bottom of the mold, or stretched along the wall for a portion of its height.

The specified technical result is also achieved by the fact that in the device for the manufacture of blocks of foamed polymeric materials, containing a mold with a bottom and side walls, forming a volume for placing a foamable polymeric material loaded from above for foaming during polymerization, each side wall of the mold is formed by one conveyor branch a conveyor belt of a vertically installed conveyor or on each wall of the mold is a conveyor belt of a vertically installed conveyor, while on the surface of the belt facing the expanding polymer material, a thin sheet material is placed, made with low adhesion to the expanding polymer material to form a separating layer, and the drive shaft of the specified the conveyor is connected to a drive for its rotation to move this thin sheet material along the volume in which the polymer material is foamed, and to ensure the relative movement of the separating layer relative to with respect to the indicated volume.

For this embodiment, the sheet material can be made of plastic film or paper.

The specified technical result is also achieved by the fact that the method of manufacturing blocks foamed polymeric materials consists in placing a separating layer on the walls of the mold to its entire height to the bottom or to a part of its height by laying a thin sheet film material or paper made with low adhesion to the expanding polymeric material, loading a foaming polymeric material into the mold cavity, holding time after the start of polymerization, in which this polymer material is foamed and the lower layers of the block are formed, and then the separating layer is displaced in the direction from the bottom at a rate close to the growth rate of the expanding part of the block.

These features are essential and are interconnected with the formation of a stable set of essential features sufficient to obtain the required technical result.

The present invention is illustrated by a specific example of execution, which, however, is not the only possible one, but clearly demonstrates the possibility of achieving the required technical result.

FIG. 1 is a first example of a device for producing blocks of foamed polymer materials;

fig. 2 is a fragment of the side wall structure according to FIG. one;

fig. 3 is a second exemplary embodiment of a device for producing blocks of foamed polymeric materials.

According to the present invention, a new design of two examples of execution of a device for manufacturing blocks of foamed polymeric materials is considered, which allows to obtain blocks with an organized homogeneous structure, while these blocks do not stick to the walls of the mold due to a decrease in adhesion between the polymerizable polymer material and the material of the wall or walls of the mold.

Within the framework of the present invention, the technical result is achieved by reducing the effect of surface tension forces by providing a relative movement of the separating layer along the walls, limiting the volume, at a rate close to the rate of change in the volume of the polymer.

To improve the quality of blocks of foamed polymer, as well as to reduce the amount of waste in block production, it is necessary to ensure the mobility of the separating layer along the volume in which the foaming takes place. The moving layer can be realized in the form of four closed (endless) transport belts, separated from the polymer by film or paper. Or to ensure the movement of the separating layer along the stationary installed side walls. Polyethylene film, paper or other material can act as a separating layer.

The effect of surface tension forces can be reduced by ensuring the movement of the separating layer along the walls limiting the volume at a rate close to the rate of change in the volume of the polymer. To improve the quality of blocks of foamed polymer, as well as to reduce the amount of waste in block production, it is necessary to ensure the mobility of the separating layer along the volume in which the foaming takes place.

In the general case, the device according to the first embodiment contains a mold with a bottom and side walls, forming a volume for placing a foamable polymer material loaded from above for foaming during polymerization (for an example of a mold with flat walls), or with a bottom and one closed side wall forming a volume for accommodating the expandable polymeric material for its foaming during polymerization (for example, the execution of a form in the form of a cylinder or similarly similar forms).

Along each side wall or along the closed side wall of the mold, there is a thin sheet material made with low adhesion to the expandable polymeric material to form a separating layer, while the thin sheet material brought out in the upper part of the mold is connected to a shaft having a drive for its rotation for lifting along the wall of this thin sheet material along the volume in which the polymeric material is foamed, and ensuring the relative movement of the separating layer relative to the specified volume.

Below is a specific implementation of this example (Fig. 1 and 2).

The device contains a shape representing a box-shaped body with a bottom 1, side flat walls 2 and an open top (in plan it has the shape of a square or rectangle, as preferred versions). The body can be made of metal, which allows you to control and regulate heat transfer through the walls of the body. However, the body can also be made of wood, plastic, composite, etc. The capacity of the body is intended for loading through the open top of the metered portion of the feedstock - expandable polymeric material 3, for example, polyurethane foam or other polymeric material. The height of the walls of the body is selected depending on the used polymer material and on the basis of the volumetric increase of this material during foaming and polymerization.

The bottom of the case is lined with foil or paper, which has low adhesion to the expandable polymer material. This film or paper is used to form a release layer that prevents the polymer material from adhering to the bottom. It is also desirable that this film or this paper have low adhesion to the polymer material. A thin sheet material 4 (web) is lined along the walls of the body, it is made with low adhesion to the expandable polymeric material to form a separating layer that excludes the adhesive seizure of the polymeric material with the wall (s) of the mold. This sheet material 4 can extend over the entire height of the side wall 2, that is, reach the bottom. Alternatively, the material 4 can be lowered along the wall to a depth of about 1/3 of the height of the wall, that is, not reaching the bottom 1.

The polymer is poured from above. The movement (pulling) of the web starts with a delay. The stretching of the web does not start immediately, approximately in the upper third of the finished block (i.e. when the foaming process reaches ~ 2/3 of the height of wall 2). At this point, problems begin without using such a method due to the occurrence of such a phenomenon as adhesion of the outer layer to the wall. The polymer closer to the bottom is less fluid and adhesion to the walls is not so critical.

A feature of this exemplary embodiment of the device is that the sheet material 4 (web) rises (moves along the wall 2 in the upward direction) along the wall and along the volume in which the polymer material is foamed, thereby providing, due to its relative movement, the separating layer between the specified volume and wall of the case. In this case, it is essential that the movement of this web (working as a separating layer) is relative to the movement (rise) of the foaming volume. That is, the separation layer moves away from the bottom at a speed close to the growth rate of the expanding part of the block.

Foaming changes the temperature fields at the walls of the mold and in the central part of the block. At the walls, polymerization proceeds somewhat faster than in the middle zone due to the fact that the walls of the mold body remove heat, lowering the temperature of this zone. The adhesive properties of the polymer material in the initial liquid state are weakly manifested, therefore, in the lower layers adjacent to the bottom of the mold, the adhesion is not so pronounced. However, in this zone, polymerization proceeds extremely quickly due to the large difference between the temperature of the polymer starting to foam and the bottom stack. Heat is quickly dissipated into the metal bottom of the case, which leads to rapid crystallization of the lower polymer layers. The expanding volume is characterized by the manifestation of pressure in the structure of the polymer material, which causes the foam to rise up and press against the side walls of the body. It is at this moment (the moment of foaming) that the foaming volume exhibits the ability to adhere to the walls of the body. Since there is also a decrease in temperature at the walls of the casing, the outer layers of foam crystallize faster than in the central part of the block (the temperature in the central part is higher than the temperature of the foam at the walls of the casing). This results in bulging in the center of the block (dome effect). Swelling is also determined by the fact that the layers of the block (foam) at the walls of the body, due to accelerated polymerization, have a lower lifting rate than the rate of lifting of the foam mass in the central part of the block.

In order to eliminate this phenomenon, according to the present invention, there is a certain period of time after the start of polymerization, during which this polymer material is foamed and the lower layers of the block are formed (so that the lower layers are formed), and then the separation layer is moved in the direction from the bottom at a speed close to the speed growth of the foaming part of the block. Separating layers along the walls of the body are moved in the direction from the bottom so that the foam layers adjacent to this layer are torn off, thereby excluding the adhesion of the foam to the walls of the body (the effect of near-wall foam braking is removed). Moreover, the speed of movement of the separating layer exceeds the growth rate of the expanding part of the block near the separating layer and is less than or equal to the growth rate of the block in its middle part when the separating layer is stationary. In addition, with this relative movement, the foam has no time to adhere to the release layer. As a result, the polymerization of the foam volume proceeds without swelling and without adhesion to the walls of the body.

Thus, we can assume that these advantages are achieved through the use of a new method of manufacturing blocks foamed polymer materials, which is based on the following steps, implemented in the following sequence:

- placement on the walls of the mold to its entire height to the bottom or to a part of its height of the separating layer due to the laying of thin-sheet film material or paper made with low adhesion to the expandable polymer material;

- loading a foamable polymer material into the mold cavity;

- the time delay after the start of polymerization, at which the foaming of this polymer material and the formation of the lower layers of the block occurs;

- displacement of the separating layer in the direction from the bottom at a speed close to the growth rate of the expanding part of the block.

For example, when using a polymer such as expandable polyurethane foam at one-step method all components of the composition are fed into the mixer and simultaneously loaded from above into the mold. They react immediately - the rise of the foam begins in 10 seconds and ends in 1-2 minutes. after mixing. In this regard, the time delay is the time sufficient for polymerization to begin not at the level of the bottom of the mold body, but above this level.

With this method, due to the choice of the speed of movement of the separating layer and the redistribution of the polymer, the upper surface is leveled. The foaming rate of a single recipe polymer will be within a narrow range. Thus, the average polymerization rate is a known value (the rate change in different processes will fit into a narrow interval with a guaranteed deviation from the average). It is also proposed to use sensors from which the foaming rate can be measured. By determining the rate at which the foam rises, the rate at which the release layer moves can be adjusted. Since the movement of the layer takes place only at the boundaries of the block, and the foaming rate is measured in the central part, by means of the connection of the foam with the layer, it is possible to align the boundaries of the block with the central part, thereby reducing waste during production.

In this example of the implementation of the device for moving (pulling out from the housing) of the separating layer, each wall of the housing is used for a separate drive 5. The film or paper is connected to the shaft, and the drive provides rotation of this shaft for lifting along the wall of the specified thin sheet material along the volume in which foaming occurs polymeric material, and providing relative movement of the separation layer relative to the specified volume. The film or paper is rigidly connected with one edge to the shaft and is wound onto the shaft into a roll. Alternatively, the film or paper can be pulled through the counter shafts 6. One drive can be used to rotate several shafts (according to the number of walls in the housing).

Nothing limits the execution of the shape body in cylindrical or oval versions in plan. However, for such structures, the implementation of the drive for rotation and winding of the separating layer may have difficulties in purely structural terms. Within the framework of the present invention, the specific design of the drives for rotation of the shafts and drives for pulling out the separating layer from the housing is not considered, since this does not relate to the essence of the claimed invention.

The second embodiment of the device for manufacturing blocks of foamed polymeric materials differs from the first in another embodiment of the walls of the mold body.

In this new device, each side wall of the mold is formed by one branch of a conveyor belt 7 of a vertically mounted conveyor 8 (conveyor). On the surface of the tape, facing towards the expandable polymer material, there is a thin sheet material (as in the first embodiment, made of polymer film or paper), made with low adhesion to the expandable polymer material to form a separating layer. Possible execution where the conveyor belt will be made of a material with low adhesion to the expanding polymer material.

The drive shaft of the specified conveyor 8 (conveyor) is connected to the drive 9 of its rotation to move this thin sheet material along the volume in which the polymer material is foamed, and to ensure the relative movement of the separating layer relative to the specified volume.

That is, instead of stationary walls, it is possible to use vertical conveyors in the entire wall height or not in the full height, which are driven in a standard way (i.e. shafts (master-slave), drive, belt, frame / frame). The conveyor does not reach the bottom.

In the example considered, the conveyors form the walls of the mold body. As a development of this exemplary embodiment, such devices can be positioned and fixed on each wall of the mold in the form of vertically mounted conveyors with the conveyor belts facing towards the foam block.

These two versions of the second device implement the same method that was discussed for the first embodiment of the device.

The present invention is industrially applicable and tested at the enterprise in the manufacture of small batches of foam blocks from foamed polymer. The tests showed a pronounced decrease in adhesion between the walls of the device mold and the polymer material, which made it possible to practically eliminate the formation of a "dome" in the central part of the blocks. At the same time, an increase in the quality (homogeneity) of the structure of the obtained foam blocks was noted. The percentage of waste and the time for finishing blocks have been significantly reduced.

Claims (8)

1. A device for the manufacture of blocks of foamed polymeric materials, containing a mold with a bottom and side walls, forming a volume for accommodating a foamable polymeric material loaded from above for foaming during polymerization, characterized in that along each side wall of the mold is placed a thin sheet material made with a low adhesion to the expandable polymeric material to form a separating layer, while the thin sheet material brought out in the upper part of the mold is connected to a shaft that has a drive for its rotation for lifting along the wall of this sheet material along the volume in which the polymeric material is foamed, and ensuring the relative movement of the separating layer relative to the specified volume. 2. The device according to claim 1, characterized in that the sheet material is made of a polymer film or paper. 3. The device according to claim 1, characterized in that the sheet material is extended along the wall to the bottom of the mold. 4. The device according to claim 1, characterized in that the sheet material is stretched along the wall for a part of its height. 5. A device for the manufacture of blocks of foamed polymeric materials, containing a mold with a bottom and side walls, forming a volume for placing a foamable polymeric material loaded from above for foaming during polymerization, characterized in that each side wall of the mold is formed by one branch of the conveyor belt of a vertically installed conveyor or on each wall of the mold there is a conveyor belt of a vertically installed conveyor, while on the surface of the belt facing towards the expanding polymer material, a thin sheet material is placed, made with low adhesion to the expanding polymer material to form a separating layer, and the drive shaft of the said conveyor is connected to the drive its rotation to move this thin sheet material along the volume in which the polymer material is foamed, and to ensure the relative movement of the separating layer relative to the specified volume. 6. The device according to claim 5, characterized in that the sheet material is made of a polymer film or paper. 7. The device according to claim 5, characterized in that the conveyor belt is made of a material with low adhesion to the expandable polymer material. 8. A method of manufacturing blocks of foamed polymeric materials, which consists in placing a separating layer on the walls of the mold to its entire height to the bottom or to a part of its height by laying a thin sheet of film material or paper made with low adhesion to the expanding polymeric material, loading into the mold cavity foaming polymeric material, time delay after the start of polymerization, at which foaming of this polymeric material and the formation of the lower layers of the block occurs, and then the separation layer is displaced in the direction from the bottom at a rate close to the growth rate of the expanding part of the block.

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