The composition of polymer concrete – main components, characteristics

A contemporary material called polymer concrete combines synthetic polymers with conventional concrete. Its qualities are improved by this combination, which makes it appropriate for a variety of uses. Knowing its composition makes it easier to see why polymer concrete is unique in terms of strength and adaptability.

Aggregates, polymer resins, and perhaps extra fillers are the main ingredients of polymer concrete. The primary building block is the aggregate, which is usually made of crushed stone, gravel, or sand. As a binder, the polymer resins take the place of the conventional cement in ordinary concrete. The improved strength and resistance of the material are a result of this substitution.

Examining the properties of polymer concrete reveals its remarkable adaptability to different environments. When compared to traditional concrete, it frequently has greater resistance to chemicals, moisture, and temperature extremes. Because of this, it is the recommended option for demanding settings and specific applications.

Types of polymer systems

Because of their qualities, products made of synthetic resins can completely replace cement concrete.

Prospective developers are becoming more aware of this kind of content, particularly those who enjoy building things by hand. However, they ignore a single feature. The term "polymer concrete" refers to a broad category of materials, each of which has a unique composition of polymer concrete as well as distinct components and preparation techniques.

These composites fall into multiple categories based on the construction polymer production technology that considers the composition of polymer concrete:

  • plastic concrete;
  • polymer cement concrete;
  • concrete polymers;
  • geopolymers.

The intended qualities of the finished product can affect the ratios, composition, and quantity of components in polymer concrete.

Group of plastic concretes

Plasto concrete is a material made without the use of cement, based instead on synthetic resins.

There are primarily two categories of content:

  1. Filled — the amount of binder in the composite is within 20–50%. The resin tightly fills all the voids between the filler and the filler.
  2. Frame — has a porous structure, since in this case, the polymer is added only to fasten the filler frame in the structure of the material. The volume of resin should not exceed 6% of the total composition of the components.

A range of synthetic resins are employed as adhesives:

  • phenol-formaldehyde resins;
  • epoxy polymers;
  • polyvinyl acetate and methacrylate polymers;
  • furfural acetone resin (FAM);
  • polyurea and polyester matrix.

The kind of filler, preparation technique, and polymer composition all affect the material’s characteristics.

Furfural acetone polymers are known to contain carcinogenic substances and have an extremely toxic odor. They can also cause suffocation and headaches. For this reason, FAM-based polymer compositions for concrete are exclusively utilized in the manufacturing of goods meant to preserve and seal subterranean pipeline systems.

It is advised to use materials like polyester, methacrylate, and epoxy for both public and residential buildings.

Plasticizers and hardeners can be added to the polymer mixture’s composition to enhance its qualities and quicken the solution’s setting time.

GOST 25246–82 states that crushed rock is used as large aggregates.

  • marble chips
  • granite crushed stone
  • granulated vermiculite
  • basalt
  • calcites
  • dolomite, etc.

Typically, the following serve as excellent filler:

  • quartz sand;
  • crushed stone screenings;
  • fly ash;
  • crushed sandstone.

The absolute volume method is utilized in the selection of plastic concrete composition.

The volume of microfiller (sand or ground rocks) is calculated by taking the area of the filler’s voids plus 10%. First, the amount of coarse filler is chosen experimentally. The amount of polymers (resin) is computed based on the results, accounting for the solution’s specified moisture content.

Take note! It is important to keep in mind that adding too much resin causes the concrete to shrink more, decreases its ultimate strength, and raises the possibility of temperature deformations.

When comparing the characteristics of plastic concrete to the cement equivalent, five benefits of using a polymer become apparent:

  • 4 times higher resistance to torsion, bending and alternating dynamic loads;
  • significantly higher moisture resistance;
  • frost resistance;
  • lower thermal conductivity;
  • inertness to chemical influences;
  • the finished product is easy to process (cutting, drilling, etc.);
  • wear resistance.

The material’s high creep and comparatively quick aging are drawbacks that are exacerbated by intermittent heating or humidification.

Take note! When using polymers and acidic hardeners, labor protection regulations must be followed; work must be done in well-ventilated areas and with appropriate clothing.

Plastobeton is widely used in road construction, hydraulic engineering, and the creation of ornamental elements to enhance local areas (see photo).

Polymer cement systems

According to the design documentation, polymer cement concrete consists of fillers, aqueous polymer dispersion, cement (Portland cement, pozzolanic cement), and fillers.

Three approaches can be used to obtain polymer cement composites:

  1. By introducing aqueous solutions of polymers into the mixture at the time of preparation – synthetic rubber or polyvinyl acetate.
  2. By adding a dispersion of water-soluble polymers and monomers (polyvinyl and furan alcohol, phenol-formaldehyde and epoxy resins) using hardeners or additional heating.
  3. By impregnating concrete to the planned depth with low-viscosity polymer compositions – Etinol varnish, styrene, urea.

For instance, the ideal ratio of the volume of polyvinyl acetate polymer to the quantity of cement in the dry mixture is 15-20%. Such ratios are optimal for the behavior of polymers and cement.

In these circumstances, the polymer solution encloses the aggregate grains and fuses them into a single framework, maintaining the continuous structure of the cement gel in polymer cement concrete.

Take note! The integrity of the cement formations is compromised by an increase in polymer volume, which lowers the strength of polymer-cement products.

Crushed rock with a maximum grain size of 20 mm, also known as quartz sand, is used as filler in polymer-cement materials. Polymer cement solutions are applied as coatings, paints, and adhesives (e.g., to prevent corrosion on reinforcement).

The composition of components known as polymer cement concrete is primarily utilized in the construction of industrial buildings’ wear-resistant floors, the restoration of airfield and road surfaces, and the creation of protective linings for tanks, communications, etc.

Concrete polymer compositions

Concrete polymers are made of hardened cement stone that has had liquid impregnations or monopolymer vapors applied to its surface. Methacrylate resins or styrene with a catalyst are typically included in the chemical composition of the polymer mixture. These materials polymerize in the product’s mineral matrix during the hardening process.

The primary drawback of traditional cement concretes is that they contain a complex network of pores, capillaries, and microdefects in their structure, which develop during product molding and hardening. The strength and resistance to harsh environments are diminished by pores and other defects, which also drastically shorten the structure’s service life.

If a polymer is added to the resulting pores, the material’s properties can be readily altered. Products or completed structures are given extra care because of this.

The following procedures are involved in creating a concrete polymer:

  • drying the product;
  • vacuuming;
  • impregnation with a polymer composition;
  • polymerization.

The following determines how successful polymer impregnation is:

  • characteristics of the original concrete;
  • drying time of the product;
  • chemical composition of the polymer;
  • impregnation and polymerization mode.

The purpose of drying the material is to get rid of water from the pores and capillaries of the concrete before adding a specific composition to them.

Deeper cleaning of capillaries and the elimination of leftover air—which hinders the polymerization of some compounds—are made possible by vacuuming. The polymerization process within the product’s pores is the primary technological step involved in producing a concrete polymer.

The accuracy with which the polymer impregnation for concrete is chosen will determine the event’s success. Since the viscosity, wetting angle, and properties of the polymer solution affect the depth of impregnation and the final properties of the product.

  • Viscous impregnations, such as petrolatum and bitumen, wet the surface to a depth of 10-30 mm.
  • Liquid monomers, methyl methacrylate or styrene, can impregnate the surface of the material to a depth of 100-200 mm in the same time.
  • To speed up and increase the efficiency of the product processing process, polymerization initiators are subjected to heat treatment (70–120°C) or exposed to radiation at normal temperature.
  • For complete impregnation of heavy concrete, 2–5% of monomer is required. For lightweight cellular concrete 30–60%.
  • The polymer network formed in the structure enhances the strengthening and reinforcing effect, which causes compression of the mineral component of the material, increases the adhesion of the cement stone to the surface of the filler.
  • When processing the material with monomers, their density increases several times, resistance to aggressive environments increases.

Concrete polymers exhibit enhanced wear resistance, high gas impermeability, and higher tensile and compressive strength compared to the original concrete.

The following products are successfully produced using this technology:

  1. reinforced cement and glass cement structures;
  2. for the production of balcony slabs, window sills, stair parts, industrial floors;
  3. for impregnating parts of desalination plants and cooling towers, strengthening foundations for equipment in machine-building shops, etc.;
  4. for processing bridge structures and road surfaces.

In order to improve its qualities and increase its durability and versatility, polymer concrete blends conventional concrete with polymer resins. Aggregates, a polymer binder, and occasionally performance-enhancing additives make up its major ingredients. The polymer binder, which partially substitutes for cement, improves adhesion, decreases shrinkage, and helps the concrete withstand chemicals. When compared to regular concrete, this combination produces a material that is stronger, more resistant to environmental changes, and has a longer lifespan.

Component Description
Resin Acts as the binding agent, providing strength and durability to the concrete.
Aggregates Includes materials like sand, gravel, or crushed stone that give bulk and stability.
Hardener Speeds up the curing process and enhances the concrete"s resistance to wear.
Fillers Increases volume and improves the physical properties of the concrete.
Additives Modifiers that enhance specific qualities such as workability or resistance to environmental factors.

Because it combines the strength of regular concrete with the adaptability of polymers, polymer concrete is distinguished by its special mixture of materials. This material improves characteristics like adhesion, durability, and resistance to moisture and chemicals by incorporating polymers into the mixture.

Traditional aggregates like sand and gravel are essential parts of polymer concrete, as are different polymer resins that serve as binders. Although these resins can differ, they usually consist of vinyl ester, polyester, or epoxy, each of which has a unique advantage for the finished product.

The versatility of polymer concrete for various applications is one of its main benefits. A wide range of building and repair projects can benefit from the flexibility, strength, and resistance to environmental factors that can be adjusted through the selection of aggregates and polymers.

In conclusion, polymer concrete’s blend of polymers and conventional aggregates produces a material with improved qualities that can be customized to meet particular requirements. It is a useful choice for both new construction and repair situations due to its adaptability and enhanced performance.

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Anna Vasilieva

Journalist with a technical education, specializing in construction topics. I can explain complex technical topics in simple and accessible language.

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