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This paper presents a method for the determination of the kinetic parameters for the oxidation‐reduction hardening reactions of unsaturated polyesters with styrene. The method was based on the measurement of the change in the specific internal electric resistance during the hardening. This paper discusses the accelerating effects of ferrocene and some of its derivatives (acetylferrocene, benzoylferrocene, 1,1′‐diethylferrocene) on the hardening of unsaturated polyesters.

Twelve pigment compositions derived from the xCaO·(50−x)ZnO·20B₂O₃·30P₂O₅·(x=10, 20, 30) and yMgO·(50−y)ZnO·20B₂O₃·30P₂O₅·(y=10, 20, 30) systems were prepared. The synthesis was carried out either by the medium‐temperature process or by the high‐temperature process followed by cooling in air and an isothermal crystallisation of the glass obtained. The pigments prepared by the medium‐temperature process achieved better corrosion results in styrene‐acrylate coating formulations, whereas those prepared by the high‐temperature process achieved better results in alkyd‐resin coating formulations. The anti‐corrosion results for the Ca‐Zn pigments were better than those for the Mg‐Zn pigments.

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

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.

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.

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

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

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.

The paper deals with using the maleinized polybutadiene as a binder in anticorrosive coating compositions. This aqueous emulsion can be as a binder mixed with the styrene–acrylate dispersion in any ratio, evaluating thus positively a series of final anticorrosive coating properties. The aqueous emulsion binder based on the maleinized polybutadiene was compared to other aqueous (alkyd, urethanized alkyd, or polyurethane) emulsions. The coatings formed by the aqueous maleinized polybutadiene emulsion and styrene–acrylate dispersion show a far higher efficiency than the coatings consisting of a styrene–acrylate dispersion alone with respect to anticorrosion protection function.

The purpose of this paper is to synthesise X₂TiO₄ spinel‐type anticorrosion pigments and YTiO₃, perovskite‐type anticorrosion pigments, where X = Zn, Mg, Ca, Sr; Y = Ca for metal protective paints.

Anticorrosion pigments were synthesised from oxides or carbonates at high temperature. The following pigments were synthesised: TiO₂ · ZnO, 2TiO₂ · ZnO, TiO₂ · 2ZnO, TiO₂ · MgO, TiO₂ · CaO, TiO₂ · ZnO · MgO, and TiO₂ · ZnO · SrO. The pigments obtained were characterised by means of X‐ray diffraction analysis, measurement of particle sizes and scanning electron microscopy. The anticorrosion pigments synthesised were used to produce epoxy coatings with PVC = 10 per cent for each synthesised pigment. The coatings were tested for physical‐mechanical properties and in corrosion atmospheres. The corrosion test results were compared with those of alumino zinc phosphomolybdate.

A spinel or perovskite structure was found in the pigments synthesised. High anticorrosion efficiency was identified in all the synthesised pigments, the highest efficiency being demonstrated in the TiO₂ · ZnO pigment of spinel structure and in the TiO₂ · CaO pigment of perovskite structure.

The pigments synthesised can be conveniently used to protect metal bases from corrosion.

The use of pigments synthesised in anticorrosion coatings for metal protection presents a new approach. Its benefits are the use and the method of synthesising the anticorrosion pigments that do not contain heavy metals and that are acceptable for the environment.

To synthesise calcium titanate with a perovskite structure as an anticorrosion pigment for metal protecting paints.

Calcium titanate was synthesised from titanium dioxide and calcium carbonate at high temperature. The pigment obtained was characterised by means of X‐ray diffraction, particle size distribution measurement and scanning electron microscopy. The pigment obtained was further characterised with regard to the parameters required for paint formulation; its specific mass was determined by oil consumption and critical pigment volume concentration. The synthesised calcium titanate was used to prepare epoxy coatings with varying contents of the anticorrosion pigment. The coating was tested for physical‐mechanical properties and in corrosive atmospheres. The results were compared with titanium dioxide that served as a starting material for calcium titanate preparation.

Calcium titanate was prepared from materials that do not add any impurities to the anticorrosion properties of the pigment. It was identified that calcium titanate of perovskite structure is a highly efficient anticorrosion pigment for paints.

Calcium titanate can be utilised for the preparation of anticorrosion paints to protect metal bases from corrosion.

The method of synthesising calcium titanate as an anticorrosion pigment is new. The literature has not yet described the use of calcium titanate as a pigment with inhibitive properties in paints. From an ecologic standpoint, the application of a new anticorrosion pigment for paints presents a highly positive trend.

Studies the spinel pigments containing Zn, Ca, and Mg cations from the point of view of reactivity with corrosive substances of acidic nature, which diffuse through the coating at activated corrosion. Proposes the mechanisms of anticorrosive activities of these pigments in an epoxy resin based binder, showing a high chemical stability. A microscopy method was used for following the diffusion of corrosive acidic substances through the film.

The paper deals with studying the anticorrosive properties of condensed phosphates and polyphosphates in the coatings. The pigments contain cation in the most cases as aluminium in a combination with zinc, strontium, calcium or a combination with all the cations. The investigated anticorrosive pigments differ in water solubility, inhibition efficiencies of their aqueous extracts and also the efficiencies in the coatings protecting steel substrate to corrosion. Two types of condensed anticorrosive pigments (polyphosphates and polyphosphosilicates) were compared. The anticorrosion properties of polyphosphosilicates are inferior to those of polyphosphates. The high anticorrosion efficiency was found at a comparative pigment, represented by zinc phosphosilicate.

The paper deals with the study of modified phosphate compounds and their anticorrosion action when incorporated in paints. The pigments commence as zinc orthophosphate, the modification of which can give phosphosilicates, phosphomolybdates, or basic phosphates. With respect to cations, the combination of zinc with calcium, strontium, barium, or aluminium, is possible. The modified anticorrosive pigments differ in their water solubility, inhibition efficiency of the aqueous extracts, and anticorrosion action, when incorporated in organic coatings. Nine types of modified phosphates were studied. The effect in coatings of organic inhibitor in the presence of anticorrosive inorganic pigments was determined.

To identify a method of evaluation as well as conditions under which corrosion in the form of flash rusting attacks steel treated with a coating of water‐borne binders.

The paper worked with soluble alkaline silicates – sodium silicate – acting as flash rusting inhibitors, while aqueous dispersion binders were used in primer paints. Sodium silicate, potassium silicate and lithium silicate were studied from this point of view. Their inhibiting properties were described with the aid of a scanning method, determination of metal weight loss and electron raster microscopy.

Sodium silicate was identified as a very good flash rusting inhibitor for applications in styrene‐acrylate water‐borne paints.

Sodium silicate, potassium silicate and lithium silicate can be used in industrial coatings as high‐performance inhibitors of flash rusting.

A coating containing corrosion defects occurring during the creation of a film loses its anticorrosion properties and provides only low anticorrosion protection against atmospheric corrosion when the film of coating is later exposed to a corrosion environment. This paper proved that silicates could be very efficient flash rusting inhibitors under certain conditions.