Properties of anticorrosion pigments depending on their chemical composition and PVC value

Abstract

Purpose

To identify the dependence of the anticorrosion efficiency of chemically varying pigments on their concentration in steel protecting paints.

Design/methodology/approach

Anticorrosion pigments from a group of nontoxic substances were chosen and compared with a chromate pigment. With all pigments, the following parameters were observed namely, oil absorption, critical pigment volume concentration value, density, extract pH, specific surface, particle size, water‐borne substances content, and the specific electrical conductivity of pigment extracts. The aqueous extracts of pigments were used to determine the corrosion loss of steel. The morphology of pigment particles was observed by means of an electron‐scanning microscope. Paints containing these pigments were formulated on the binder basis of an epoxy resin. The paints prepared were subjected to measurement of physical‐mechanical properties such as hardness and resistance in deep drawing. Paints containing anticorrosion pigments were subjected to corrosion tests in a SO₂ condenser chamber, salt spray cabinet and to a test according to Machu and Schiffman.

Findings

The experimental investigations revealed the absolute values of the anticorrosion effects of individual pigments as well as dependence of efficiency on the concentration of the pigments in the paints. It was found that environment‐friendly pigments achieved comparable or even better anticorrosion efficiency than toxic strontium chromate.

Research limitations/implications

The anticorrosion properties of the paints concerned can be tested in paints by means of atmospheric exposure such as the Florida test.

Practical implications

The results find their application in the formulation of anticorrosion paints for industrial applications with environment‐friendly effects.

Originality/value

This research paper presents the results of the anticorrosion effects of a great number of industrially used pigments. Based on this paper, the formulation of highly effective steel‐protecting paints can be optimised.

Citation

Kalenda, P., Kalendová, A. and Veselý, D. (2006), "Properties of anticorrosion pigments depending on their chemical composition and PVC value", Pigment & Resin Technology, Vol. 35 No. 4, pp. 188-199. https://doi.org/10.1108/03699420610677181