Wood plastic moulds. Do-it-yourself plastic molding. Hauling device and cut-off saw

The production of lignocarbohydrate wood plastics is a new production. The problem of obtaining plastic materials from crushed wood particles without the addition of binders due to the decomposition products of wood components has long occupied researchers. Many variants of piezothermal treatment of wood particles were proposed, which differed in modes, but in essence all these methods implied the processing of wood particles at high pressures and pressing temperatures, in hermetic molds. Subsequently, the plastics obtained in this way were called piezothermoplastics.

At present, two methods for obtaining piezothermoplastics have been proposed in our country:

1. The one-stage method, developed at the Belarusian Technological Institute, involves grinding wood to a state close in particle size to wood flour, and pressing it in sealed molds at a pressure of 250-300 kg / cm 2 and a temperature of 190-200 ° C subsequent cooling to 20°C without relieving pressure.

2. The two-stage method, developed at the Leningrad Forestry Academy, involves preliminary partial water hydrolysis of wood particles in an autoclave, followed by pressing the dried, partially hydrolyzed material in a mold in a hot press. Preliminary hydrolysis will reduce the pressing pressure for some hardwood press materials to 150 kg/cm2 and the hot pressing temperature to 160°C.

At the department of wood science and construction business and in the problematic laboratory of wood plastics of the Ural Forest Engineering Institute under the guidance of prof. From 1962 to the present, V. N. Petri has been conducting comprehensive studies of new materials - ligno-carbohydrate wood plastics obtained by using the reactivity of wood components (natural lignins and polysaccharides), without adding thermosetting resins or other binders to wood particles.

The authors of the new method, in contrast to the supporters of piezothermoplastics, believe that when obtaining plastics, wood should not be subjected to deep destruction, but only to mild influences during piezothermal processing, in which, at the first stage of processing, partial hydrolysis of polysaccharides (primarily water-soluble and easily hydrolysable) occurs with the formation of some the amount of organic acids, which carry out the hydrolytic cleavage of the natural lignocarbohydrate complex, since it is known that at least small amounts of an acid catalyst are needed to destroy the chemical bond between lignin and carbohydrates.

As a result of these processes, not monomers are formed, but larger molecules that retain the natural reactivity of the main components of wood - carbohydrates and lignin. Wood should not be subjected to deep destruction in the manufacture of plastics, since this destroys the reactive components of natural wood.

In the process of piezothermal treatment, it is also necessary to provide opportunities for subsequent interaction between the reactive components of individual wood particles in order to synthesize new lignocarbohydrate complexes. Due to this, the formation of durable and water-resistant plastic from wood particles occurs. New materials named lignocarbohydrate wood plastics(LUDP). Ligno-carbohydrate wood plastic (LUDP) is a new board material obtained as a result of hot pressing of wood particles without the addition of binders. Ligno-carbohydrate wood plastics have a number of features that make their production cost-effective:

1. The main advantage of LUDP, from this point of view, is that there is an unlimited amount of raw materials for their manufacture. These are wood particles of any of the most common coniferous (pine, larch, spruce, cedar, fir) and hardwood (birch, aspen, etc.), as well as their mixtures.

The production of LUDP can be established in any region of our country where logging and woodworking enterprises operate, since plastics can be made from any waste from logging and wood processing, as well as from firewood (without limiting the content of rot and bark).

On the basis of technical and economic calculations, it was established that the minimum capacity of the workshop for the production of LUDP is 3.5-4 thousand m 3 of plates per year; the need for raw materials for such a workshop is 10-12 thousand m 3. Consequently, the production of LUDP, in contrast to the production of particle boards, can be organized at small enterprises.

2. Ligno-carbohydrate wood plastics are obtained by using the reactivity of the components of the wood itself, i.e. without adding thermosetting resins or other binders to the wood particles.

3. The technological process for the production of LUDP compared to the production of particle boards is simpler, since there are no technological operations for the preparation of binders and their mixing with wood particles.

4. For the manufacture of LUDP, standard pressing and other equipment is used, used for the production of chipboard and mass-produced by the domestic industry.

Main technical properties flat single-layer LUDP the following:

1. Appearance and coloring. After pressing, LUDP boards have a middle, darker (conditioned) part and a light edge along the periphery, or a substandard part of the board. Substandard part of the plate at optimal conditions pressing does not exceed 10 cm. When using large boards, a 10 cm wide edge is only 2-5% of the area of ​​the pressed board. For example, when the size of the pressed plates is 3100X1100 mm, the edge with a width of 10 cm is 2.5% in area. The width of the substandard part of the plates can be reduced.

The color of the conditioned part of the board, pressed under optimal conditions, depends on the wood species from which the plastics are made, but is always much darker than that of the original wood and ranges from light to dark brown. The bark breaks the uniformity of color. By tinting the wood particles of the outer layers of the carpet being formed and by making slabs lined with various decorative materials, it is possible to change the color and appearance plates.

2. Surface quality. Boards made from small and flat wood particles have a smoother and more even surface than boards made from thick and coarse wood particles. When pressing plastics from small wood particles on well-finished (better polished) pallets, the boards have a smooth, shiny surface.

3. Warping. Warping of LUDP depends on the thickness and design of the plates. Thin slabs have more buckling than thick slabs. Three-layer slabs warp less than single-layer slabs, and veneered slabs slightly more than non-glued ones. In order to avoid warping of the LUDP slabs during conditioning, the rules for laying the slabs must be strictly observed and the conditions for their conditioning - drying must be observed.

4. Density. The density of lignocarbohydrate wood plastics cannot be less than 1 g/cm 3 . Only at this density is ensured that the minimum degree of compaction of the pressed mass, at which the necessary contact and the possibility of chemical interaction between the individual particles of wood is achieved.

5. moisture absorption. LUDP to a certain extent retains one of the main features of wood - to absorb moisture from humid air. With an increase in the content of hygroscopic moisture in plastics, their mechanical properties decrease:

a) LUPD with a density of at least 1.2 g/cm 3 have a swelling of 7-10%, water absorption of 5-12%, a total moisture content of 20-22%;

b) LUDP with a density of 1.20-1.15 g/cm 3 ; swelling 10-12%, water absorption 12-15%;

c) LUDP with a density of 1.15-1 g/cm 3 ; swelling 18-25%, water absorption 20-26%.

6. Thermal properties. The material used for floors in residential and industrial buildings is characterized by a heat absorption coefficient, which should not exceed 10 kcal / m 2.

Ligno-carbohydrate wood plastics 10-11 mm thick make it possible to arrange floors by laying them directly on a concrete base.

7. Biostability. LUDP have a high anti-rot resistance, which is 4-5 times higher than that of pine wood.

Mechanical properties of LUDP. Flat single-layer uncoated LUDP boards can be divided into three groups.

Group A - static bending strength of at least 270 kg / cm 2 (density more than 1.2 g / cm 3), group B - static bending strength of at least 220 kg / cm 2 (density 1.2-1, 18 g/cm3); group B - static bending strength of at least 120 kg / cm 2 (density 1.15-1 g / cm 3).

The physical and mechanical properties of lignocarbohydrate wood plastics obtained from spruce logging residues are as follows: static bending strength is 170-190 kgf/cm 2 , swelling in 24 hours is 8-11%, and the density is 1.2 g/cm 3 . Plastics made from crushed (mixture 1:1) of birch and aspen have a static bending strength of 176 kgf/cm 2 , swelling in 24 hours - 16% and a density of 1.18 g/cm 3 .

Technological process of production is generally the same for all types of single-layer uncoated lignocarbohydrate plastics. The only difference is that for each specific type of raw material used for the manufacture of LUDP, different preparation of raw materials and different modes of pressing and conditioning plastics are required. Therefore, the organization of industrial production of plastics at a particular enterprise should be preceded by research work aimed at clarifying the technology of their manufacture from available raw materials. These studies can be carried out in parallel with the design and construction of a plastics workshop.

AT general view the technological process of production of LUDP consists of the following main operations: preparation of raw materials, drying of raw materials, dosage of wood particles, formation of a carpet (package), cold pressing of a carpet (package), hot pressing and cooling, hot pressing mode, trimming of plates, conditioning - drying of plates - plastics.

Scheme technological process production of LUDP by hot pressing from sawmill and woodworking waste using one hydraulic press.

Branches, small-sized stems, rotten wood chips, etc. are crushed on a chipper or crusher and fed by a conveyor or pneumatic conveyor to the bunker of chopped wood pulp, which can also receive sawdust, shavings or screenings from technological chips, chip production, etc. To obtain conditioned wood particles, wood pulp, previously cleaned of metal inclusions using a metal detector, is passed through a DO-5.7 chipper, and then through DM-3 cross mills. The openings of the sieve drum of mills for some species are reduced to 3 mm. After crushing, the wood particles are sucked in by a fan and transported to a cyclone installed under the hopper.

The dosing device of this hopper allows you to change the amount of chips issued per unit of time, which is necessary to maintain the required temperature regime in the drying chamber.

Chips are loaded into the installation chamber by a screw conveyor.

The fluidized bed dryer consists of two sections installed in parallel. The drying agent is heated air. Air is supplied by fans. The crushed grain dried to the required moisture content enters the sluice feeders through the drain thresholds of the drying chambers, and then into the suction pneumatic conveying pipeline. The air, passing through the layer of chips in the drying chambers, carries along the dust, which settles in a cyclone with an increased purification factor. Cleaned from dust, but with high humidity, the air is released into the atmosphere, and the dust is sent along with the bulk of the material to the dry chip hopper.

From this hopper, the chips are evenly fed by the dispenser to the belt conveyor 2 to the feeders and distributed among the forming machines with fractionating rollers. Machines lay carpet on pallets. The sides of the carpet are formed by two vertical belt conveyors. Then the pallet with the loose carpet laid on it is moved by another section of the chain conveyor to press the carpet into the cold pressing press. The carpet is pressed under pressure of 25 kg/cm2 for 1 minute.

Before loading the package into a cold press, a duralumin gasket is placed on top using a crossbar with suction cups. This contributes to the uniform heating of the package and allows you to get a plate with a high-quality surface on both sides.

The packages are accumulated in the loading rack of the press. After the bookcase is completely filled, all press bays are loaded simultaneously.

After the end of pressing, all the plastic slabs are simultaneously unloaded into the unloading stack, from which they are sequentially, starting from the bottom, fed to the longitudinal and transverse conveyors.

Plastic slabs are transferred from the lower pallet to the three-saw sizing and trimming machine by the removal mechanism. Pallets, after cleaning and applying talc on them, are sent under the forming machines.

Plastic plates, after trimming the light edges, are sorted. Rejected slabs are cut into smaller ones with defective areas cut out. After sorting, high-quality boards are stacked on spacers and loaded into conditioning-drying chambers with the help of a traverse trolley. After unloading from the chambers, the slabs are placed in dense piles in a heated room. Then they are packaged and sent to the warehouse of finished products for shipment to the consumer. ( Technological operations, following the cutting of plastic plates, are not shown in the diagram.) It is possible to increase the productivity of the LUDP workshop by increasing the size of the plates, the number of floors of the presses or their number.

High physical and mechanical properties of LUDP, beautiful appearance and the possibility of manufacturing plates large sizes allow them to be used in construction as a structural and finishing material for laying floors, filing ceilings, manufacturing built-in furniture, partition walls, door panels, window sill boards, for cladding walls and panels in public buildings, in kitchens and corridors of residential buildings, etc., in furniture and other industries, as well as a substitute for solid wood, chipboard and fibreboard and others sheet materials. The plates have a smooth surface and are well finished with transparent and opaque varnishes and paints using conventional technology. Finishing with transparent furniture varnishes can be done with preliminary tinting of the surface with water-soluble and other dyes in any color while maintaining the texture of the plates.

Thus, when crushing branches and thinner, the output of conditioned wood chips is on average 50% of the total crushed mass. This conditioned chips can be used to produce semi-cellulose, the production of chipboard and fibreboard, and 50% of non-conditioned chips can be used to produce ligno-carbohydrate wood plastics or fertilizers.

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UDC 674.812

V.G. Dedyukhin, V.G. Buryndin, N.M. Mukhin, A.V. Artemov

PRODUCTION OF PRODUCTS BY PRESSING IN CLOSED PHENOPLASTIC MOLDS WITHOUT ADDING BINDERS

The results of studies of the study of the technological properties of a press composition of wood particles without the addition of binders and the physical and mechanical properties of plastics from these compositions are given; the influence of low-molecular (organic and inorganic) modifiers, as well as water in the process of plastics formation, was studied.

Key words: wood plastic, carbamide, Raschig fluidity, sanding dust, plywood.

The stock of wood in Russia is estimated at 80 billion m3. The degree of its use is 65 ... 70%, and only 15 ... 17% are processed by the chemical and chemical-mechanical methods (the world level is 50 ... 70%). Hydrolysis enterprises accumulate 1.5 million tons of hydrolysis lignin per year in terms of dry matter.

One of the rational directions for the efficient use of woodworking waste is the production of press materials (wood pressing masses) from them based on phenol and urea-formaldehyde resins. However, the introduction of 11 to 35% synthetic binders into these compositions increases the cost of boards and makes them environmentally unsafe.

Therefore, wood-based plastics obtained without the addition of binders are of great interest. The feedstock can be not only small wood particles, but also hydrolytic lignin and plant residues of annual plants (flax and hemp fire, cotton stalks, straw, etc.). In the work of A.N. Minin, such material is called piezothermoplastic.

In USFTU, work is underway to obtain materials from wood and other vegetable waste without adding binders: since 1961 in open molds (between heated plane-parallel plates) - lignocarbohydrate wood plastic, since 1996 in closed molds - wood plastic without binder (DP-BS).

The technology for producing boards and products from wood-based plastics without a binder is not widely used due to the long pressing cycle, since the plastic is cooled in a mold under pressure (low productivity of equipment and tooling, and high heat consumption). We have proposed a technology for pressing products based on the use of external molds and air as a heat and coolant carrier. At the same time, productivity increases by a factor of 5 or more compared to traditional technology for such press materials, and heat consumption is significantly reduced.

One of the disadvantages of wood press compositions without the addition of binders is their low fluidity. For example, the fluidity of DP-BS from woodworking waste (fraction 0 ... 2 mm) according to the method of pressing a flat disk sample at a moisture content of 10% is 78 mm, and at 20% - 95 mm; the Rashig fluidity of this press composition at a moisture content of 10% is 9 mm, and at 20% it is 29 mm.

A cheap raw material for the manufacture of DP-BS is grinding dust from the production of plywood (TTTP-F) and particle boards (ShP-DStP). Thus, with a volume of production of chipboard of 100 thousand m3/year, the amount of formed SHP-chipboard is 7.5 thousand tons. The paper shows that ShP-DStP can be used in the production of phenolic plastic grade 03-010-02, which meets the requirements of GOST 5689-86 (see table).

Composition and properties of phenolic plastics based on wood flour and ShP-chipboard

Index Index value for filler

Wood flour ShP-DStP

Compound, %:

phenol-formaldehyde resin 42.8 37.5

wood filler 42.6 42.0

urotropin 6.5 7.0

mummy 4.4 -

lime (magnesium hydroxide) 0.9 0.7

stearin 0.7 0.6

kaolin - 4.4

nigrosine 1.1 -

Properties:

bending strength, MPa 69 66...69

impact strength, kJ/cm2 5.9 5.9...7.0

electrical strength, kV/cm 14.0 16.7.17.2

Dependence of the properties of the press material based on ShP-F without the addition of a binder on humidity (modification with urea was carried out at a moisture content of 13%): a - shear resistance; b - modulus of elasticity in bending; c - fluidity according to Rashig; g - fluidity on the disk

The purpose of this study is to develop a DP-BS formulation based on ShP-F and to find the optimal modes for pressing products with properties close to those of phenolic 03-010-02.

In terms of fluidity, DP-BS based on ShP-F is significantly inferior to phenolic plastics, so it can be used to manufacture products of a simple configuration. The fluidity of the material according to Raschig and on the disk, depending on its moisture content, is shown in the figure.

It is known that the modification of wood with ammonia significantly increases its plasticity. The optimal amount of ammonia is 5%. As a source of ammonia, it is proposed to use carbamide, which decomposes under pressing conditions:

1CHN2 - C - 1CHN2 + H20 -> 2Shz + C02. O

The amount of ammonia and carbon dioxide, tg, formed during the decomposition of urea mc can be calculated by the formulas

there \u003d mk / 1.765; tug \u003d 0.733 tk.

In our opinion, the use of carbamide is more appropriate, since the resulting carbon dioxide creates a weakly acidic environment, which contributes to the polycondensation of lignin and the easily hydrolysable part of cellulose - hemicelluloses. This coincides with the opinion of the authors of the papers.

Water in the process of obtaining wood plastic without the addition of a binder is necessary as a wood plasticizer and a chemical reagent involved in reactions with wood components.

According to, for the occurrence of chemical processes occurring during the formation of plastic from pine particles at a pressure of 2.5 MPa, the initial moisture content of wood should be 7 ... 9%. When using hardwoods (aspen, alder), the initial humidity should be slightly higher - 10 ... 12%. To give the wood plasticity, the moisture content, which depends on the type of wood and the pressing pressure, must be even higher.

In addition, when using carbamide as a modifier, an additional amount of water is required for its decomposition (see the above diagram). The amount of water for the passage of the reaction can be calculated by the formula TV = 0.53 there.

Therefore, in the formation of DP-BS based on ShP-F using carbamide as a modifier, the optimal water content should be about 13%.

To modify the press composition based on ShP-F, 9% wt. carbamide. This made it possible to significantly increase the ductile properties of the press material. For example, the Raschig fluidity, with a moisture content of the source material of 13% wt., increased 3.5 times, the disc fluidity increased from 75 to 84 mm, the flexural modulus increased from 263 to 364 MPa, and the shear resistance determined according to, decreased from 2.6 to 1.5 MPa

Thus, the following conclusions can be drawn:

Using the method of mathematical planning of an experiment of type Z2, the influence of ShP-F humidity (Х1 = 11 ± 5%) and pressing pressure (Х2 = 15 ± 10 MPa) on the properties of DP-BS (pressing temperature 170 °C) was studied;

When processing the results of experiments, adequate regression equations were obtained in the form of a second-order polynomial:

¥,(ayug) = 34.9 + 6.6 X! + 16.9 X2 - 1.4 X? - 4.3 X22 - 3.0 Xx X2;

G2 (D:,) \u003d 34.5 - 21.8 X ~ 76.7 X2 + 26.3 X2 - 3.8 X22 + 75.5 X X2.

BIBLIOGRAPHY

1. Bazarnova N.G. Influence of urea on the properties of pressed materials from wood subjected to hydrothermal treatment / N.G. Bazarnova, A.I. Galochkin, V.S. Krestyannikov // Chemistry of plant raw materials. -1997. - No. 1. -S. 17-21.

2. Buryndin V.G. The study of the possibility of using grinding dust chipboard for the production of phenolic plastics / V.G. Buryndin [et al.] // Technology of wood boards and plastics: Interuniversity. Sat. - Ekaterinburg, ULTI, 1994. - S. 82-87.

3. Vigdorovich A.I. Wood composite materials in mechanical engineering (reference book) / A.I. Vigdorovich, G.V. Sagalaev, A.A. Pozdnyakov. - M.: Mashinostroenie, 1991.- 152 p.

4. Dedyukhin V.G. Wood-based plastics without the addition of binders (DP-BS): Sat. Proceedings dedicated to the 70th anniversary of the Faculty of Engineering and Ecology of the Ural State Forest Technical University /V.G. Dedyukhin, N.M. Mukhin. - Ekaterinburg, 2000. - S. 200-205.

5. Dedyukhin V.G. The study of the fluidity of the wood press mass without the addition of a binder /V.G. Dedyukhin, N.M. Mukhin // Technology of wood boards and plastics: Interuniversity. Sat. - Ekaterinburg: UGLTA, 1999. - S. 96-101.

6. Dedyukhin V.G. Pressing facing tiles from pressing mass without adding a binder / V.G. Dedyukhin, L.V. Myasnikova, I.V. Pichugin // Technology of wood boards and plastics: Interuniversity. Sat. - Yekaterinburg: UGLTA, 1997. -S. 94-97.

7. Dedyukhin V.G. Pressed fiberglass / V.G. Dedyukhin, V.P. Stav-ditch. - M.: Chemistry, 1976. - 272 p.

8. Doronin Yu.G. Wood press masses /Yu.G. Doronin, S.N. Miroshnichenko, I.Ya. Shulepov. - M.: Lesn. prom-st, 1980.- 112 p.

9. Kononov G.V. Chemistry of wood and its main components /G.V. Kononov. - M.: MGUL, 1999. - 247 p.

10. Minin A.N. Technology of piezothermoplastics /A.N. Minin. - M.: Lesn. prom-st, 1965. - 296 p.

11. Otlev I.A. Handbook for the production of particle boards / I.A. Otlev [i dr.]. - M.: Lesn. prom-st, 1990. - 384 p.

12. Plate materials and products from wood and other lignified plant residues without the addition of binders / ed. V.N. Petri. - M.: Lesn. prom-st, 1976. - 360 p.

13. Obtaining, properties and application of modified wood.- Riga: Zinatne, 1973.- 138 p.

14. Shcherbakov A.S. Composite technology wood materials/A.S. Shcherbakov, I.A. Gamova, L.V. Melnikov. - M.: Ecology, 1992. - 192 p.

V. G. Dedyukhin, V. G. Buryndin, N. M. Mukhin, A. V. Artyomov Producing Items out of Phenoplasts by Pressing in Closed Press Molds without Adding Binding Agents

The research results of technological properties of presscomposition made of wood particles without adding binding agents and physicomechanical properties of plastics from these compositions are provided. The influence of low-molecular (organic and inorganic) modifiers and water in plastic formation process are studied.

Plastic is a universal material. It has found wide application in the manufacture of various components and parts in both industrial and household appliances. Products from it are used in the design of interiors of residential premises and offices.

A variety of material, called liquid plastic, allows you to create a wide variety of shapes and sizes of crafts. This makes it possible to implement original design solutions. How to make liquid plastic at home?

Materials for manufacturing

To make liquid plastic with your own hands, you need to prepare the following:

• glass or metal container;
• acetone;
• Styrofoam.

In this case, the amount of acetone used depends on the desired volume of the finished product.

If you want to make liquid plastic with your own hands, the recipe for its preparation will be based on dissolving foam in acetone. To do this, use It is a packaging container for various household and electronic equipment.

How to make liquid plastic with your own hands

Step by step recipe the preparation of the named material looks like this:

1. Open the container with acetone and pour the liquid into the glass container so that its level from the bottom is approximately 1 cm.
2. Polystyrene foam must be broken into many small pieces, each of which will be easily placed under the thickness of the solvent.
3. Do-it-yourself liquid plastic can be made by dropping each piece into a container and waiting for it to completely dissolve.
4. Styrofoam should be added to the container until it stops melting. Then you need to wait 5-10 minutes for the unused acetone to evaporate.
5. After that, a viscous mass is formed at the bottom of the container, which can be used to produce a variety of products.

Knowing how to make liquid plastic, remember that the complete hardening of the mass lasts 20-30 hours. Therefore, the manufactured part cannot be removed from the mold during this period of time.

Substance should be applied rubber spatula small size. The movements must be smooth. Liquid plastic must be stretched on the surface to be treated. If it is used to fill gaps, it is better to use brushes with a hard bristle in the work. They need to "push" the mixture into the gaps. After the plastic has hardened, it is recommended to apply another layer of the substance.

The described tool has long been sold ready-made. It only needs to be heated in a water bath or in special equipment. Also, a building hair dryer is often used for this.

As a rule, liquid plastic is produced in dense packages. Its terms and conditions of storage are strict. The temperature in the room where it is located should not fall below 15 degrees. Otherwise, the tool will lose performance:

• viscosity;
• elasticity;
• hardness after hardening;
• practicality;
• durability.

The cost of liquid plastic is quite high. That is why it is better to do it yourself.

Precautionary measures

Acetone is a very dangerous liquid that has an extremely negative effect on the human body. Therefore, do-it-yourself liquid plastic is allowed to be made only with strict observance of the following precautions:

1. Before working with acetone, you must carefully study the instructions for its use. It is listed on the container label.
2. Special sealed goggles should be used. They will protect your eyes in case of drops and fumes of liquid. Working without them can cause serious eye injury.
3. Acetone is toxic and should only be used in a well ventilated area. In this case, it is necessary to use respiratory protection equipment.
4. It is highly flammable. Therefore, do-it-yourself liquid plastic is made away from sources open fire. Smoking is strictly prohibited during work.
5. Residues of acetone must not be drained into the sewerage system.
6. At the end of the process, as well as after pouring the finished plastic into molds, you must thoroughly wash your hands.

Applications of liquid plastic in decoration

For decoration, the product has been used for a long time. After its application, an elastic film appears on the treated surface. It is highly waterproof and UV resistant. The material protected by such a film is not afraid of aggressive detergents. The smooth surface has a pleasant sheen and retains its characteristics for many years.

Liquid plastic in window works

Most of the newly installed plastic windows gaps in the connection area. To exclude such a phenomenon, all parts of the window structure that are interconnected are treated with the described substance. After drying, it creates an elastic sealed film on the surface. Do-it-yourself application of liquid plastic on windows is possible after making the material according to the above method.

Means in anti-corrosion treatment

Liquid plastic is also characterized by a high degree of adhesion with the processed metal surface. This property of the substance began to be used in the anti-corrosion treatment of steel. Liquid plastic is applied to the surface without prior priming. It dries out after a few hours. After that, a film is formed on the surface, which will protect the material from rust.

Attention! Price for 1 piece The product is released in packages 2 pcs. You must enter a multiple of 2.

plastic mold for making paving slabs“Wood cut medium-38. The mold is intended for the manufacture of paving slabs by injection molding (vibrocasting) from a cement mixture. With the correct selection of the composition of the mixture and the use of vibrocompaction, products of high strength and frost resistance are obtained, which are superior in durability and aesthetics to vibrocompressed products.

The standard depth of the form allows you to form the finished product thick: 5cm.
Casting size: 38 x 38 cm.
Finished product surface texture: texture.

Medium-38 wood cut mold material: high-strength ABS plastic, superior in performance to polypropylene and PVC. The mold has greater wear resistance and durability (250-300 castings). The wall thickness of the mold is 2-3 mm. It is possible to repair the mold if damaged and remove scratches with a solution made from acetone with a small amount of ABS plastic dissolved (cut off from the edge of the mold).

To form a quality product, it is desirable to use PAN fiber, plasticizing additives and. Can be used to paint tiles. The finished product can be removed from the mold no earlier than 24-48 hours later. Otherwise, due to insufficient gained strength, the number of scrap increases. For reference - Graph of concrete hardening depending on temperature. When extracting, it is forbidden to exert a shock effect on the back of the mold. We are ready to provide detailed information on the technology of application of the form, the recipe of the mixture and necessary equipment to any buyer of our products.

The composition of architectural concrete for vibrocasting paving slabs "Wood cut medium-38

For products with a thickness of > 2 cm, it is optimal to prepare a mixture with a cement-sand ratio (C: P) = 1: 3 by weight. Proportions necessary materials given for calculation per 1 m3 of the finished mixture. For the calculation, it is necessary, knowing the total area and thickness of the products, to calculate the required volume of the mixture and, accordingly, adjust the data given in the table.

1. (C) cement(M500 D0) - 475 kg. (396 l.)
2. (P) sand(quarry, washed) - 1425 kg. (950 l.)
3. water(25-30% of cement) * — 142 l.
4. plasticizer(1.2% of cement)** — 5.7 kg. (5.2 l.)
   or
   plasticizer (3.0% of cement) *** — 14.25 kg. (12 y.)
5. (0.075% total mass) — 1.5 kg.
6. pigment colored (5% of cement) **** — 23.75 kg

* Calculation of water in the table is made for Glenium-115 plasticizer. The required amount of water depends on the type of plasticizer used. The effectiveness of the MasterGlenium-115 hyperplasticizer is more than 2 times higher than that of the C-3 superplasticizer, which makes it possible to reduce the W/C (reduce the amount of water) and thereby increase the strength, frost resistance and, as a result, the durability of the finished product.
** Only 1 type of plasticizer is used at choice in the dosage indicated in the table. Mixing different plasticizers is unacceptable.
*** Plasticizer C-3 in the table is indicated (mass) in the form aqueous solution in a mass ratio of 1:2 (1 kg of C-3 plasticizer per 2 liters of water).
**** The amount of pigment indicated is optimal for obtaining a saturated color when using the method of volumetric coloring of concrete.

Water repellent "Akvasil" to increase the frost resistance of concrete products

An additional increase in the service life of the product "Wood cut medium-38" can be achieved by using organosilicon for protection. The use of a silicone water repellent will protect a product made of concrete (as well as wood or stone) from moisture, which will increase the frost resistance of the product and preserve color saturation. The use of water repellent "Akvasil" in the recommended dosage provides reduction of water absorption of concrete by 10 times.

The water repellent "Akvasil" can be used in the manufacture of concrete products by volumetric or surface hydrophobization:
1) Surface hydrophobization- A solution of concentrate in water is used in a volume ratio of 1:10 for concrete. The solution is applied to the surface of the products with a roller, brush or sprayer in 2 layers with an interval of 2-3 minutes.
2) Volumetric hydrophobization- a water repellent (concentrate, not a solution) is introduced into the concrete mixture in an amount of 0.4–0.5% by weight of the binder (cement).

You can buy a plastic mold "Wood cut medium-38", as well as all the necessary additives in concrete, pigments and a water repellent, in the Legobeton online store. Qualified consultations on the choice and application of the form and additives - for free!. The warehouse is conveniently located 10 minutes from Khoroshevo metro station. Courier delivery or sending shopping mall across Russia.