(otherwise, casting stone) - a material that combines strength and beauty natural stone With affordable price(thanks to cheap mineral additives) and ease of manufacture. The possibility of using almost any aggregate (sand, granite and marble chips, glass and many others) guarantees variety. And the presence of a polymer binder makes them durable, exposed to water and overheating.
Let's consider typical technological processes for the manufacture of polymer concrete, as well as the possibility of creating it yourself.
What will be required?
To get the product you need:
- A filler of a sufficiently large fraction (sand, crushed stone, coarsely crushed glass).
- A finer grinded aggregate that reduces the cost of the material. It is a powder of graphite, quartz or andesite.
- Binder - it will need about 5 percent. In this capacity, one of the polymer resins is used. For example, polyester (unsaturated), urea-formaldehyde, furan, epoxy.
- Hardeners, plasticizers, special modifiers, dyes.
- Mold release lubricant and top coat gel coat.
Production methods
The production process can take place in batch or continuous technology.
- In the first case, the containers used for the manufacture of the material must be washed after each completed cycle. But it is possible to make polymer concrete in the most ordinary bucket or concrete mixer.
- Continuous technology is mainly applied to large industries. At the same time, special injection molding machines, dispensers and automatic mixers work together, organizing a single chain.
The following video talks about the manufacture and spraying of lightweight polymer concrete:
Process
For the manufacture of cast stone you will need a mold well coated with a special release agent (otherwise it will be impossible to remove the finished product). The form can be made of silicone, fiberglass, metal or even chipboard (budget option).
- A layer of gelcoat of the desired color is applied to the release paste.
- A composite mixture is placed inside the mold, consisting of the above ingredients, previously well mixed in a concrete mixer. In large industries, where the volumes are very solid, the mixture is put into the mold using a concrete paver. If the items are small and technological process is periodic, it is done manually.
- Now it is necessary that the laid mixture is subjected to vibration (vibration compaction). This procedure takes approximately two minutes. At the plant, a resonant vibration platform is used for this, at a small production site - a vibrating table.
In the conditions of production at the plant for the production of polymer concrete, if necessary, heat treatment is carried out for faster hardening of the parts. In other cases, they wait for the natural completion of this process.
We will talk about machines, molds and other equipment for the production of polymer concrete products below.
Necessary equipment
Features of choice and costs
Those who dream of aiming at continuous technology and solid volumes by organizing a large industrial production require special conveyor equipment. Which will include machines for dosing, mixing, casting, finishing, as well as a mechanized warehouse.
All this will cost a tidy sum of several million dollars. If we confine ourselves to turnkey branded equipment, then the costs will be much less - from 30 to 50 thousand dollars.
But still, it is not always possible to find money for a purchase, especially in our difficult time. However, you can get by with even lower costs. If you purchase all the necessary machines and other things separately. And something to make yourself. Below is more about this option.
List of equipment and devices
So, here is a list of equipment and devices that you can not do without:
- Vibrating table - ready will cost about 27 thousand rubles. If you want to save money, weld the table yourself using two-millimeter metal corners (60s). We weld a vibrator to the table industrial type- ready.
- A stirrer that will combine all the components into a homogeneous mixture. If you purchase a powerful vacuum device European quality, you will have to pay about 10 thousand dollars. But you can also use a domestic concrete mixer or construction mixer. It will be much cheaper - the cost depends on the volume and power. Even cheaper is to make a mixer yourself from an iron barrel and an electric drive with a gearbox.
- You will also need a compressor system with a gun. Without it, it will not be possible to apply the gelcoat evenly. The gun costs from 50 to 100 dollars. You can take automobile compressors - two pieces from ZIL will be enough. They are connected in parallel and attached to metal platforms installed on a strong frame.
- Molds made of fiberglass or silicone are not yet widely available for sale. They can be ordered for specific products (for example, window sills) from a specialized company. Or make molds yourself, starting with a cheaper material - chipboard with lamination.
- AT without fail an exhaust hood will be needed - at the casting stage, production is characterized by harmful fumes. Accordingly, we get personal protection: gloves, respirators.
- For finishing works need electric tools: grinding and polishing machines. And also a drill, a jigsaw, a grinder, a milling cutter (if necessary).
We will talk about emissions into the atmosphere from the production of polymer concrete below.
This video will also tell about another method of manufacturing polymer concrete:
Air emissions from such production
As mentioned just above, during casting, the release of harmful components is present.
- In particular, it is styrene, which is contained in resins used as a binder. As soon as we open a hermetically sealed container with such a resin, the poisonous gas begins to evaporate.
- In addition, the hardener is also extremely dangerous (as a rule, it is methyl ethyl ketone peroxide). However, it is not volatile and requires only the protection of hands with rubber gloves.
These facts force polymer concrete manufacturers to carefully equip the casting room, making it hermetic, installing a powerful exhaust above the table, not forgetting about their own protection (respirator). And if all these measures are observed, and the air leaving the hood is cleaned, then there will be no emissions into the atmosphere (after all, the room is airtight).
How to make elastic polymer concrete yourself (with your own hands), read below.
DIY creation
And now we will talk about how to make small products from fashionable cast stone on our own, spending a minimum of money. For example, it can be flower pots, countertops, window sills (especially popular, as they are warmer than marble or granite).
Room selection and arrangement
First you need to think about the room - you need 80 square meters total area. It is advisable to look for a suitable house somewhere on the outskirts. and 12 square meters immediately it will be necessary to fence off for the casting room, and you will have to try to seal all the cracks as much as possible. So that the styrene does not leak.
In the center of this room we make a table on a frame of iron corners, covering it with a chipboard top. We expose its surface according to the level - this is important! Above the table we install a hood - a metal box with an electric motor.
To make it light, we mount the lamps on top daylight. In the next room we put the same table - for finishing and other work. Here we will place the tool and containers for drying chalk and sand (metal low boxes).
Required raw materials
Required raw materials:
- River quartz sand (packed in 20 kilograms). It must dry well.
- Sifted chalk - we also dry it.
- Polyester resin - in buckets of 20 liters is bought.
- Hardener, gelcoat, release paste.
Manufacturing process
- You will need a clean plastic bucket for stirring, a 450-watt perforator and a construction mixer (we will attach a perforator to it by welding a perforating drill - we get a mixer).
- We make a form from laminated wood boards making it collapsible. It is convenient to apply the separating paste with a brush, rubbing with a nylon stocking.
- We dilute the gelcoat with resin (adding 10 percent of it) and apply with a flute brush. We do this twice. We make sure that the hairs from the brush do not stick.
- After mixing the resin with the hardener in a clean bucket, add 15 percent chalk, and then sand in portions. The mass should become viscous. To remove air bubbles, tap the bucket on the floor from time to time.
- Once ready, pour the solution into the mold. Now let's smooth the surface: two people take their hands on the form (certainly equipped with handles) and, lifting it, tap it on the table. The mixture is left (for 40 minutes) and exit the casting room.
- After hardening to a “rubber” state - this can be determined by a very hot surface and a special sound when tapped - we take the product out of the mold (disassemble it) and turn it over with the pouring side down. Let it harden completely, then sand and polish.
Security measures: when weighing the resin, as well as working with it, with the gelcoat and with the mixture poured into the mold, we work only in a respirator, under a hood. We add the hardener with a syringe, wearing rubber gloves.
The following video will tell you how to make polymer concrete with stains with your own hands:
The main difference between polymer concrete and ordinary concrete is that during its production, high-molecular organic compounds are added to the initial solution. If to speak plain language, then in the composition of such a solution the role of a binder is played by resins: epoxy, polyvinyl, polyester, polyurethane, methyl methacrylate or others. Also, components such as solvents, hardeners, catalysts and others are added to the composition of this material to improve various properties.
This material is used for outdoor or interior decoration various buildings and premises, as well as road construction, landscape design and in the manufacture of various small architectural forms. Thanks to the ability to vary the consistency of the material during its production, polymer concrete can be used on both horizontal and vertical planes.
Characteristics of polymer concrete
The main components for the production of geopolymer concrete are slag, ash, water glass, binder resins. During the polymerization of such a solution, a monolith is formed, which, both in strength and in most other specifications significantly superior to conventional concrete. Compared with the solution, which is prepared on the basis of Portland cement, it has several advantages:
- increased adhesion to virtually any surface;
- high curing speed;
- excellent indicators of vapor permeability;
- increased resistance to bending and stretching;
- strength and wear resistance;
- resistance to temperature extremes and acidic chemical compounds.
Also, this building material has a small weight, it is completely environmentally friendly. If we talk about the shortcomings, then this material has only one. Due to the fact that it was developed not so long ago, and high-quality components are used for its production, it is quite expensive. However, there is every reason to believe that in the very near future it will become the most popular view concrete used in construction.
Features of the preparation of polymer concrete
In addition to the components already mentioned, PVA glue, latexes and water-soluble resins are most often used as additives for geopolymer concrete. If PVA is used, then only the type should be selected in which polyvinyl alcohol is used as an emulsifier.
When such a mixture dries, a strong film forms on the surface, which swells over time and absorbs water. That is why during the hardening of the material it is not allowed that it comes into contact with air with a high moisture content.
The optimal amount of various additives for such a material is most often established empirically. However, collateral High Quality solution is the correct ratio of cement and polymer components. The volume of polymer components should be no more than 20% of total mass cement. And the volume of water-soluble resins is not more than 2% of the mass of cement. The highest quality can be achieved when using polyamide or epoxy resins, as well as polyethylene-polyamine hardeners.
In the preparation of geopolymer concrete, as well as conventional, you will need a concrete mixer. Water and cement, specially designed for polymer concretes, are first poured into it (ordinary Portland cement cannot be used, since it does not fit the characteristics). Then slag and ash are added to the solution in equal parts, after which it is thoroughly mixed. After that, polymer components and additives are added.
With rare exceptions, the technology of construction, restoration or repair work provides for the use concrete solutions. All these materials differ in brand, class and some other parameters, for example, moisture resistance. And all have a common similarity - cement is used as the only binder component in these mixtures. But modern industry has launched the production of other similar building materials, one of which is polymer concrete.
Its fundamental difference is that special ingredients, resins, are added as an astringent to the usual sand-cement mixture. They are gradually introduced during the preparation of the solution. Polymer-based concretes are suitable for surface finishing both inside and outside buildings, pouring floors, stairs.
Composition and fillers
For the preparation of these concretes, fillers and binders are also used. Given the special qualities of the polymers, the ratio between the components can vary from 5:1 to 12:1.
As with traditional analogues, polymer concrete contains fractions different sizes, and unlike cement grades, and finely dispersed. Given that these materials are widely used, including for operation in conditions of direct contact with aggressive compounds, substances with increased resistance to chemical attack (for example, quartzite, basalt, tuff) are used as fillers.
Astringent ingredients:
- The cheapest are furan polymers. But the strength is also low.
- More quality concretes, which include polyesters (unsaturated).
- by the most the best options materials containing epoxy resins are considered. They combine strength, ductility, wear resistance. However, their price is quite high.
Manufacturing
There is no definite answer to the question of how to make polymer concrete. All sources speak of an experimental way of obtaining required composition. It is necessary to ensure that when the applied mixture dries, it forms an elastic elastic coating. Much depends on the place of installation, on what result you want to achieve. There is general recommendation that of the total mass of the solution polymer additives should be approximately 1/5 part.
Much depends on what class of concrete you need to get. Therefore, you will have to vary the percentage of resins, hardeners. It is also necessary to take into account the type of polymer binder that is decided to be used, since each has its own specific properties. Individual sources indicate that the use of epoxy resins involves the replacement of cement with slag, ash and liquid glass. In all other respects (mixing), the procedure is the same.
Distinctive features of polymer concrete
- High water resistance. Allows you to significantly simplify the technology of work in areas where structural elements of the structure are exposed to intense exposure to liquids. By purchasing polymer, or natural concrete, you can significantly save on waterproofing and reduce the total time of work.
- Resistance to aggressive environments, low temperatures.
- Indicators mechanical strength significantly exceed the similar characteristics of concretes based on cements: for bending - up to 10, for compression - up to 3 times.
- Small specific gravity which significantly increases the range of applications.
- The property of elasticity allows it to be used in areas subject to dynamic loads. Can be applied on planes with any orientation: horizontal, vertical, inclined.
- Excellent adhesion, regardless of the base material.
- The curing time is less than that of cement.
- The ability to achieve perfect evenness of the coating. Surfaces finished with polymer concrete are easy to maintain.
Most of the inhabitants are sure that polymer concrete and cement-polymer concrete These are two names for the same material. In fact, they are completely different building mixtures having high performance strength.
Cement is not added to polymer concrete (plastic concrete), and various polymers act as a binder. into polymer cement concretes Portland cements mixed with polymer additives are added.
There are two types:
1. Filled - high-molecular organic compounds fill the voids between the particles of the filler (gravel, crushed stone, quartz sand).
2. Frame - the voids remain unfilled, and the polymer serves only to fasten the particles of the mineral filler together.
In the first case, the amount of the mixture ranges from 20 to 50%. In the second case, it does not exceed 6%.
It is considered a high-strength material in which aqueous dispersions of polymers (vinyl chloride, vinyl acetate, styrene, latexes, polyamide resins, and others) act as additives that improve performance. Their use allows better side change the properties of building materials and improve its technical performance.
Applications, production and sales
Compound
Resins are added to polymer concrete more often than others:
- epoxy;
- polyurethane;
- methyl methacrylate;
- polyvinyl.
Various plasticizers are added to resins to improve elasticity and increase resistance to stretching, and hardeners to reduce the setting time. The composition of cement-polymer concrete also includes Portland cement.
Gets its characteristics due to the organic binder. This contributes to the fact that free particles of gravel or crushed stone are fastened together, turning into a strong monolith with a complete absence of cracks. As moisture evaporates, a special film forms on the surface, adding strength and increasing adhesive properties (adhesion to other surfaces).
Thanks to this, polymer concrete becomes extremely resistant even to serious loads, as well as to the effects of acids and sudden changes in temperature. The strength becomes even higher if the solution is kept in conditions of low humidity (40-50%).
Characteristics:
- moisture resistance;
- wear resistance;
- high chemical resistance;
- resistance to temperature extremes;
- increased tensile strength;
- absence negative impact on living organisms;
- high level of adhesion to surfaces;
- fast curing;
- good breathability.
The only thing that can become a stumbling block and cross out all the advantages of this building material is its high cost. It is unlikely that you will be able to buy polymer concrete cheaply. The price directly depends on the amount of the connecting element used. Filled polymer concrete is always more expensive than frame concrete. Additives can be painted in absolutely any color. This also affects the final cost of the building mixture.
Production
As additives in the production of polymer concrete, water-soluble resins, PVA and latexes are most often used. When ready mix dries, a film is formed on the surface of its particles, which swells when hit a large number moisture. However, this does not affect the strength characteristics.
The only correct ratio of components in the recipe does not yet exist. But most often, manufacturers mix cement with additives not exceeding 20% of the cement part.
The highest quality cement solution is obtained with a water-soluble polyamide or epoxy resin and a hardener (polyethylene-polyamine).
The production of a cement-polymer mixture is as follows:
1. Pour into the concrete mixer special water for polymers with a small amount of cement;
2. Are added the same number ash and slag.
3. The solution is mixed.
4. Polymeric and other additives are added.
5. Finally knead.
Application
The material can be used for landscape design(paths and terraces), internal and exterior finish walls, floors and facades of buildings.
Designers and architects love it because it is easily shaped and can be applied by hand and by mechanical means. A special stamp is applied to the surface of the poured concrete a certain number of times, imitating various natural structures (stone, cobblestone, wood, paving slabs and others). The dried surface can subsequently be painted with desired color acrylic based paints.
They can also be used to decorate fireplace portals, fences, plinths, stairs, pools, borders, barbecue areas, building facades.
Polymer coatings for concrete are able to give the material additional improved properties of wear resistance, durability and strength. Thanks to them, the monolith is able to last more than 20 years.
Manufacturers and cost
In Russia, the following companies are engaged in production and supply: TeoChem LLC, BASF CJSC (a representative office of the German concern BASF), DI-Trade LLC, the Moscow representative office of DUROCEM ITALIA, Zika LLC (a representative of the Swiss company SIKA), LLC "Topbeton"
The price of a polymer concrete self-leveling floor starts at around 400 rubles per 1 m 2, a further increase in the cost depends on the high cost of polymer additives, working conditions and footage.
The development of the chemistry of synthetic binders and polymers predetermined the emergence of a new material in the construction industry, known as polymer concrete. And although the first patents for its manufacture appeared 80 years ago, practical use the novelty received only in the 60s of the last century. As the name implies, the developers managed to obtain a building material based on resins and polymers, which, in terms of composition and characteristics, can completely replace modern cement and slag-cement concretes.
What is polymer concrete
Often building terms able to confuse a non-specialist or a novice builder, a lover of building with his own hands. At the household level, polymer concrete includes all types building materials, which include cement, water and polymer resin.
In fact, the technology of building polymers divides such materials into several groups:
- Polymer concrete is a mixed composition, which includes mineral ballast or filler, polymer binder, hardener, stabilizer and adhesive, without the use of cement and water;
- Polymer cement concrete - a material obtained by adding a water-soluble polymer composition to the composition of the parent cement mortar or concrete;
- Concrete-polymer materials are cured concrete or cement stone, subjected to additional processing with liquid or vapor polymers, usually the composition of the liquid includes styrene with a catalyst, which polymerizes in the thickness of the mineral matrix of concrete.
Note! Polymer concretes obtained on the basis of thermosetting and epoxy resins are also called plast concretes.
The properties of polymer concrete depend on the composition of the used binder, resin, filler and method of preparation. Such materials are successfully used not only in construction, but also in mechanical engineering, in the chemical industry and even in the production of household items and furniture. The technology of using various mineral fillers to reduce the cost of producing castings from synthetic resins began to be used in the 80s of the last century, and in early XXI century, almost 80-90% of plastic products are made using polymer concrete technology, which contains resin and finely ground ballast powder.
To obtain construction grades of polymer concrete, compositions based on five main varieties of synthetic resins are used:
- Phenol-formaldehyde and urea-formaldehyde polymers;
- Epoxy matrices, including those modified with furan resins;
- Methacrylate and polyvinyl acetate polymers;
- Furfural acetone matrix, or FAM for short;
- Polyester and polyurea resin.
Note! FAM is one of the few types of binders used for the production of so-called faizol concretes, which have unique properties extinguish and dissipate vibrations by an order of magnitude better than the most viscous grades of cast iron.
The composition of furfural acetone resins includes volatiles with very bad smell capable of causing suffocation and headache, which are pronounced carcinogens. Therefore, they are used only for the production of polymer concrete, conservation steel structures pipelines and communication systems. For residential premises, polymer concretes are most often used, which include polyester resins, epoxy and methacrylate oligomers.
In the composition of polymer concrete, the resin content is relatively small, from 10 to 15%. The rest is a mineral filler - marble chips, ground ash, crushed dolomites, calcites, granulated vermiculite, clinker and ordinary Portland cement. Quite rarely, as part of polymer concrete, a resin with an organic filler based on modified wood fibers mixed with chopped basalt fiber.
Why change ordinary cement mortar to polymer concrete
Modern grades of concrete based on cement and sand work well in huge masses, where the static load is constant and there are no shocks, vibrations or complex bending moments or torsional forces. In all other cases, it is necessary to introduce special additives into the composition, use reinforcement with expensive metal, make multilayer structures, or completely replace cement concrete with metal or polymer concrete. In some variants, it is technologically easier to cast a part building structure from polymer concrete than to use reinforced concrete. For example, during the construction of product pipelines.
If we compare the characteristics of polymer concrete with ordinary concrete, there are five advantages of using polymers:
- 3-4 times higher bending strength, torsion and alternating dynamic load. The resin in polymer concrete makes the material behave like metal;
- The presence of polymers in the composition ensures low water absorption and high frost resistance of polymer concrete structures;
- Polymer concretes of certain grades, containing fine particles, have low thermal conductivity, if necessary, they can be used without insulation even in the manufacture of floors and ceilings ground floor, basements;
- Good machinability by cutting, drilling, without the risk of chipping or cracking;
- Epoxy resins in the composition of polymer concrete make them inert to chemical active substances, organic solvents, gasoline, oil, chlorinated hydrocarbons, hot and sea water. In shipbuilding, cladding, floors, floorboards, protective panels and deck elements are made from polymer concrete.
Note! The main "value" of the polymer concrete composition is the possibility of obtaining a high quality casting, without shells, striae, cracks, with "programmed" mechanical and strength characteristics. Characteristics are easily adjusted by changing the composition of the material.
For example, in the manufacture of a pipeline, polymer concrete is used with the addition of polyvinyl alcohol or liquid glass. Alcohol in the composition of concrete improves the wettability of cement grains, removes air from the intergranular space and helps the hydration process. After the pipeline is cast, due to the intense binding of water, the inner surface of the concrete pipe quickly dries up and becomes covered with cracks. To make it strong, hard and wear-resistant, concrete is treated with a liquid solution of polystyrene in styrene. The result is a surface that rivals cast iron in terms of performance and durability.
Today, the cost of polymer concrete is still quite high, so there is no talk of a complete replacement of cement in the composition of the material, but as new resins are developed, the prospect of switching to polymer concrete becomes more and more real.
Features of the use of various grades of polymer concrete
Most people will be surprised to learn how many household items are polymer concrete in their composition. For example, from polyester resin and filler from finely ground natural stone- Gabro, basalt, marble, calcite are produced artificial stones, sculptures, decorative elements and facing tiles for stone finishing. Tabletops and window sills are cast under the stone from inexpensive polymer concrete, the cost of a similar product made of natural marble or granite will cost 2-3 times more.
Communication elements are made from epoxy polymer concretes - pipes, tanks, wells, catchment trays and even entire collectors. With the help of polymer cement casting, it is quite easy to repair concrete bearing structures, seal the screed and restore the tightness of the container. Polymer concretes, which include epoxy resin, have exceptionally high adhesion, so they are often used to repair holes and joints in concrete panels in high-rise buildings.
From methacrylate filled with ground glass powder and marble dust, it is possible to obtain such a high-quality imitation of natural stone that professional restorers borrowed and used this material for work. Large granules of marble or calcite can be introduced into the composition. On the basis of polymer concrete, all polymer plasters, putties, tile adhesives, grout, that is, almost all materials for decorative finishes houses.
Separately, it is necessary to remember self-leveling floors. In this case, quartz sand crushed into dust is used instead of glass filler. The most expensive grades, which include forced-curing modified methacrylate, after curing, give a perfectly smooth surface that is superior in strength to cement screed.
How to make the simplest polymer concrete at home
In order to prepare polymer concrete with your own hands, you will need two components, resin and filler. For the simplest version of polymer concrete, you can use epoxy glue or resin, hardener and filler. It is best to use cement washed and dried in the composition of the material. river sand or granite dust, which you can get hold of in any workshop for the manufacture of monuments.
The resin is diluted with acetone or an alcohol-acetone mixture. Various brands epoxy resin require their own brand of solvent, therefore, for the preparation of polymer concrete, it is necessary to select a thinner. A hardener is added to the resin, stirred and a thinner is added to the composition. After 10 minutes, the filler can be added in small portions to the adhesive mass. After another 3-10 minutes of mixing, the polymer concrete will be ready for use.
Conclusion
Similarly, it is possible to prepare polymer concrete based on PVA, acrylic resin and sand, oil paint and cement filler. Finally, you can add a mixture for self-leveling floors to the composition, which will allow you to use the material for casting parts for finishing ceilings and walls, columns, stucco moldings, pilasters. In any case, such a composition will be cheaper, and the quality of the products will be no worse than that of purchased options.
