Anticorrosion properties of glassy-crystalline borophosphates in water-borne coating system

• Published in: Pigment & resin technology 2008-01, Vol.37 (1), p.16-20
• Main Authors: Mošner, P, Veselý, D, Koudelka, L, Kalendová, A
• Format: Article
• Language: English
• Subjects: Corrosion inhibitors; Corrosion tests; Diffraction; Oil consumption; Paints; Particle size; Phosphates; Pigments; Protective coatings; Studies; Water
• ISSN: 0369-9420; 1758-6941
• DOI: 10.1108/03699420810839666

Purpose - The purpose of this paper is to synthesise glassy and crystalline Ca-Zn and Sr-Zn borophosphates.Design methodology approach - Anticorrosion pigments on the basis of glassy and crystalline borophosphates formulated as 20CaO-30ZnO-20B2O3-30P2O5 and 20SrO-30ZnO-20B2O3-30P2O5 were synthesised. The pigments prepared were characterised by means of X-ray diffraction and their physical-chemical properties were determined. The pigments synthesised were used to prepare water-borne styrene-acrylate coatings with a 10 per cent anticorrosion pigment content. The coatings underwent corrosion tests in a humid environment with SO2 content and a test in a salt mist environment. The corrosion tests results were compared with industrially produced pigments.Findings - As the glassy phase reduces the anticorrosion efficiency of the coatings with the Sr-Zn borophosphate content decreases too. In case of the Ca-Zn borophosphates, the maximum anticorrosion efficiency was detected with regard to a pigment containing 75 wt% of the glassy phase.Practical implications - The pigments synthesised can be conveniently used in water-borne coatings to protect metal bases from corrosion.Originality value - The application of the synthesised glassy-crystalline borophosphate pigments in anticorrosion water-borne coatings to protect metal bases from corrosion presents a new method. The use and the method of synthesising these anticorrosion pigments are beneficial.