Epoxy-ester Coatings Research Articles

Properties of Organic Coatings with Nonisometric Ferrite Particles

Abstract Ferrite pigments were synthesized through a high-temperature process during a solid phase. Zinc ferrites were prepared from hematite, goethite, magnetite and specularite entering into reaction with zinc oxide at temperatures ranging from 650 °C up to 1,150 °C. The nature of the initial raw material, primarily the shape of its particles, affects the shape of the particles of the synthesized zinc ferrite. The formulated zinc ferrites had a rod-shape, lamellar, and/or isometric shape. The shape of the particles of synthesized zinc ferrites was studied with regard to its effects on the mechanical and corrosion resistance of organic coatings. The obtained pigments were characterized by means of X- ray diffraction analysis and scanning electron microscopy. The synthesized anticorrosion pigments were used to prepare epoxy-ester coatings and water-borne styrene-acrylate coatings that were subjected to post-application tests for physical-mechanical properties and anticorrosion properties.

Mixed Metal Oxides with the Structure of Perovskite for Anticorrosion Organic Coatings

Mixed metal oxides pigments of TiO2.ZnO, 2TiO2.ZnO, Zn2TiO4, MgTiO3, CaTiO3, TiO2.ZnO.MgO, and TiO2.ZnO.SrO were synthesized from corresponding oxides or carbonates at high temperature. The obtained metal mixed oxides were characterized by means of X-fray diffraction analysis, measurement of particle sizes and scanning electron microscopy. The synthesized metal mixed oxides were used to produce epoxy-ester coatings with PVC = 10% for a synthesized pigment. The coatings were tested for physical-mechanical properties and in corrosion atmospheres. The results of corrosion tests were compared with standard alumino zinc phosphomolybdate.

Properties of organic coatings depending on chemical composition and structure of pigment particles

ZnO, ZnO/core, MgO and MgO/core oxides were synthesized; their morphology was evaluated and their impact on the physical properties of the paint film was assessed. The binder used in the studied coatings was epoxy-ester resin. The physico-mechanical properties and the anticorrosion efficiencies of the pigmented paint films were determined. All the synthesized pigments have good anticorrosion efficiency in epoxy-ester coatings. The synthesized pigments can be conveniently used in coatings protecting metal bases against corrosion.

Corrosion inhibition efficiency of organic coatings with content of polyaniline phosphate

Polyaniline (PANI) phosphate was synthesised in an aqueous environment containing ammonium peroxodisulfate and phosphoric acid. Polyaniline was characterised by means of scanning electron microscopy. Epoxy ester coatings containing 3–24 vol.-% of PANI as corrosion inhibitor were formulated. The testing of anticorrosion efficiency of PANI as corrosion inhibitor was based on the accelerated corrosion tests in the environment of condensed water, NaCl mist, and condensing water containing SO2. The prepared PANI exhibits inhibitive effects in corrosion reactions progressing on a steel base under the layer of an organic coating.

Anticorrosion efficiency of organic coatings depending on the pigment volume concentration of polyaniline phosphate

Polyaniline (PANI) was synthesized by reaction in an aqueous solution of ammonium peroxodisulfate and phosphoric acid. PANI was characterized by means of scanning electron microscopy and its physical–chemical properties were determined. Simultaneously with the synthesized PANI epoxy-ester coatings containing 3, 5, 10, 15, 20 and 24 vol.% of PANI as a corrosion inhibitor were formulated. The coatings were tested for their mechanical properties, film hardness and corrosion resistance. The testing of the anticorrosion efficiency of PANI as corrosion inhibitor was based on accelerated corrosion tests: in condensed water, NaCl mist, and condensing water and SO 2. The prepared PANI displayed inhibition effects in corrosion reactions progressing on a steel base under the organic coating. The synthesized PANI provides good anticorrosion efficiency in an epoxy-ester coating. The studied system does not contain any heavy metals harmful to the environment.

Electrochemical, chemical and barrier action of zinc dust/anticorrosive pigments containing coatings

This work deals with the study of anticorrosive efficiency of coatings containing a combination of zinc dust and non-metallic pigments. Eight non-metallic anticorrosive pigments combined with zinc dust VM 4P16 were used. For each combination of pigments were prepared three or four types of epoxyester coatings with different pigment volume concentration. All coatings were pigmented to a degree of Q=65%. The effectiveness of these systems was rated according to the resistance of the coatings exposed to 5% salt spray in a salt-spray cabinet with NaCl solution and humidity condensation and to SO 2 atmosphere in a humidity cabinet. The obtained results were analyzed by subjective evaluation methods.