BASIC ASPECTS OF FORMATION OF PROTECTIVE POLYMER COATINGS

ОСНОВНЫЕ АСПЕКТЫ ОБРАЗОВАНИЯ ЗАЩИТНЫХ ПОЛИМЕРНЫХ ПОКРЫТИЙ

Хабибулина Галия Сабиржановна

магистрант, кафедра нанотехнологий и материаловедения Карагандинский технический университет,

РК, г. Караганда

Набоко Елена Петровна

научный руководитель, канд. техн. наук, доц., кафедра нанотехнологий и материаловедения, Карагандинский технический университет,

РК, г. Караганда

ABSTRACT

In technology, anticorrosive polymer coatings are widely used, which are used for chemical, mechanical or combined protection of various materials from external destructive factors. In this regard, the purpose of this article is to review the main components in the formation of protective polymer coatings.

АННОТАЦИЯ

В технике широко применяются антикоррозионные полимерные покрытия, используемые для химической, механической или комбинированной защиты различных материалов от внешних разрушающих факторов. В связи с этим целью данной статьи является обзор основных составляющих в образовании защитных полимерных покрытий.

Keywords: polymer, adhesion, elasticity, moisture permeability, hardness, dielectric constant.

Ключевые слова: полимер, адгезия, эластичность, влагопроницаемость, твердость, диэлектрическая проницаемость.

The protective properties of polymer coatings are mainly determined by the chemical resistance of their base - the polymer (Table 1.1.), Which constitutes the base of the coating, the permeability of the coating and its adhesion to the surface of the product. The effect of various media on protective polymer coatings is always accompanied by the influence of many factors, of which temperature is the most important. Its effect on the rate of chemical and physical processes in a coating in contact with an aggressive medium can be expressed by the equation

                                                                   (1)

k — service life of the coating, h;

А and В — constant values determined experimentally;

Т — absolute temperature, К.

The properties of protective polymer coatings can be determined by the purpose and type of a particular polymer coating, but the following are distinguished as the fundamental properties of this type of materials: adhesion, tensile strength, a complex of elastic properties (bending ɛp,%; elasticity, etc.) [1].

Adhesion - adhesion - the bond between dissimilar surfaces brought into contact. The reasons for the appearance of an adhesive bond are the action of intermolecular forces or forces of chemical interaction. Adhesion causes the adhesion of solids - substrates - with the help of an adhesive - an adhesive.

Table 1.

Some properties of varnish fluoroplastic coatings

* The upper temperature limit for the operation of enamel coatings is 50 ° C higher.

Adhesion of a liquid to a solid - a decrease in free energy per unit surface of an adhesive joint in an isothermally reversible process [2].

The properties of protective polymer coatings can be determined by the purpose and type of a particular polymer coating, but the following are distinguished as fundamental properties of this type of material: adhesion, tensile strength, a complex of elastic properties (bend ɛp, %; elasticity, etc.)

Mechanical adhesion, in some cases, certainly plays a significant role, but it cannot explain all cases of adhesion of coatings on the surface of substrates, since it is known that good adhesion properties are observed in coatings applied to completely smooth surfaces that do not have pores and cracks.

According to the molecular theory proposed by Debruin, adhesion is due to the action of van der Waals forces, dispersion forces, forces of interaction between permanent or between permanent and induced dipoles, as well as ion-dipole interaction or the formation of hydrogen bonds. Debroyn substantiated his theory with the following facts:

1) the same adhesive can bond different materials;

2) chemical interaction between the adhesive and the surface of the substrate due to their usually inert nature is unlikely.

Thus, according to McLaren, adhesion is a purely surface process due to the adsorption of certain sections of the adhesive molecules with the surface of the substrate. McLaren proves the correctness of his ideas by the influence of a number of factors on the adhesion value (temperature, polarity, nature, size and shape of adhesive molecules, etc.) and derived dependencies that quantitatively describe adhesion. So, for polymers containing carboxyl groups, it was found that the strength of the adhesive bond (A) depends on the concentration of these groups:

A=k[COOH]_n,                                                                  (2)

[COOH] - the concentration of carboxyl groups in the polymer;

k and n - constants.

Список литературы:

1. Басов, П.И. Техника переработки пластмасс: учеб. для вузов. - М.: Химия, 2005. - 528с.
2. Гончаров И.Л. Разработка составов защитных полимерных покрытий и устройств для их нанесения: дис. канд. техн. наук. — Воронеж., 2005. — С.8—9.