secrets and correct proportions - Instruction + Video

secrets and correct proportions - Instruction + Video By its chemical structure, epoxy resin is a synthetically oligomeric compound. Epoxy resin materials have found their application in various industries. As a rule, free epoxy is not used. It can show its properties after a polymerization reaction in combination with a hardener.

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If you combine different types of epoxy resins and hardeners, you can get different materials: hard and hard (hardness exceeding hardness of steel), or soft.

Epoxy resins are resistant to chemical acids and alkalis, halogens, soluble in acetone and esters without forming a film. Epoxies do not emit volatiles after curing and may exhibit slight shrinkage.

Types of epoxy resins

secrets and correct proportions - Instruction + Video
Types of epoxy

Epoxy resin is a kind of synthetic resin. It gained its distribution in the fifties and immediately became popular due to its universal consumer properties.

The temperature regime of epoxy resin curing can vary from -10 to + 200 ° C, depending on the type of compound used .

Epoxy resins can be divided into cold and hot curing types:

  • Cold curing epoxy resin is used, as a rule, in everyday life, in enterprises with low power and where there is no heat treatment.
  • For the manufacture and production of high-strength products that can withstand high temperature differences and active chemicals and additives, hot curing is used. With this method, the densest network of polymer molecules is formed. The developed epoxy compounds can cure in moisture and damp conditions, as well as in sea water.

Application of epoxy resins

Epoxy materials have become widely known all over the world since the middle of the last century.

But recently, the nature of their application has changed significantly.

The traditional use of epoxy resins is in the following areas:

  1. For impregnating special glass yarns
    secrets and correct proportions - Instruction + Video
    Epoxy

    and fiberglass. As an impregnation and for gluing parts, epoxy resins are used in the aviation industry, electrical engineering, mechanical engineering, radio electronics, shipbuilding, and boat hull workshops.

  2. Waterproofing coating. Epoxy is used for waterproofing floors and walls in swimming pools and basements.

  3. Chemical resistant coatings. Paints and mixtures for building decoration. Impregnants for increasing the strength of concrete, wood, etc., as well as their waterproofing.
  4. Manufacture of fiberglass products in the electronics industry, construction and household.

Concept hardener

An epoxy mixture consists of two components.When they are mixed, the polymerization process begins. In this case, the polymerizing component is usually called a hardener.

secrets and correct proportions - Instruction + Video Different combinations of resins and hardeners result in a wide variety of epoxy compositions.

Tertiary amines, phenols and their analogs are used as solidifying agents.

The ratio of epoxy resins to hardeners has a wide range and depends on their composition.

Epoxy is a so-called thermosetting plastic, that is, the reaction that takes place between epoxy resins and hardeners is irreversible. The cured resin will not dissolve and will not melt like a thermoplastic.

Ratio of resin and hardener

secrets and correct proportions - Instruction + Video
Resin and hardener

With an excess or insufficient hardener in the epoxy composition, it can lead to negative consequences : strength, as well as resistance to heat and active chemical additives and substances. If the level of hardener is insufficient, the product may become sticky due to unbound epoxy.

With an excessive level of free hardener, a gradual precipitation on the surface of the polymer occurs. In modern compounds, the ratio of 1: 2 or 1: 1 is increasingly common.

Preparatory work for the application of epoxy resin

Regardless of the type of surface, when using epoxy, a number of rules must be observed for good adhesion:

  • Degrease the surface . secrets and correct proportions - Instruction + Video Before using epoxy resins, you need to treat the surface, remove traces of fat and oil products. Surface cleaning is carried out with detergents and solvents.

  • Lack of glossy surface . To give the surface a glossy shine, the top layer of the product is removed by grinding. Surfaces that are small in size are hand sanded with sandpaper. A large area is treated with grinding machines.
  • If several coats of paints and varnishes are required during repairs, then they must be applied to the previously incompletely cured sticky layer.

  • Depending on the requirements for the finished product, the bottom layer is sprinkled with fine sand, after the layer hardens, the excess sand is removed and a new layer can be applied.

Advantages and advantages of epoxy resins

Epoxy resin has great advantages over similar materials:

  • adhesive bond of high strength;
  • slight shrinkage;
  • minimal moisture permeability in a hardening state;
  • increased stability and wear resistance;
  • excellent physical and mechanical properties and options.

Epoxy adhesive. Its properties and uses

Epoxy resin has gained fame as an adhesive.

Epoxy resins are most often used to create special protective layers and for gluing parts with a non-porous surface.

secrets and correct proportions - Instruction + Video
What can be glued with epoxy glue

In a universal adhesive, as a rule, special epoxy compositions with high adhesion to different materials are used.

Their final properties after curing vary over a wide range. The composition of the glue is elastic and hard. When working in a domestic environment, there are compositions that do not require exact adherence to the proportions of resin with a hardener. It can range from 100: 40 to 100: 60.

These formulations include a cold hardener.

Epoxy glue is considered a versatile and reliable agent due to its high-quality adhesion and bond strength. This glue is used in various fields, from shoe workshops to mechanical engineering and aircraft construction.

Method of making epoxy adhesive

secrets and correct proportions - Instruction + Video
Proportions hardener

To obtain the adhesive, the epoxy must be mixed with a small amount of hardener at room temperature. The standard proportion of epoxy and hardener is 1:10.

When mixing, no exact proportion is required and a slight overdose of hardener (1: 5) is permissible. Small volumes are usually mixed by hand.

Cure rate of epoxy resins

Many people believe that if you take more hardener than the required rate, then cure will be much faster. But the simplest and most common way to accelerate polymerization is to increase the temperature of the reaction mixture . With an increase in temperature by 10 ° C, it can speed up the process by 2-3 times.

The temperature of the mix and the type of hardener will be the main factors affecting the rate of final cure.

Bulky products from epoxy resins

To make a large product from epoxy resin can be difficult. Such a product should be free of air bubbles, and its surface should be transparent.

secrets and correct proportions - Instruction + Video
Epoxy table

It should be noted that the curing is thicker and on the surface should go evenly. With a product thickness of 2 mm, the material is applied in layers after the initial solidification of the previous layer.


There are special forms for epoxy resins. Before use, the form is greased with technical vaseline or other fats. Using powder dyes, the product can be given any color. At the end of the work, the product is initially kept at room temperature. After 3 hours, the process of primary polymerization begins, after which the product is warmed up in the oven for a faster curing process (up to 6 hours).

At room temperature, the full cure can take up to 7 days, and the addition of triethylenetetramine makes the surface sticky.

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