Pitting corrosion of stainless steel occurs in solutions of organic acid, such as tartaric acid, in an electrolyte solution with methanol. However, methanolic solutions containing at least one organic halide and at least one organic hydroxyacid and some water provide reduced pitting corrosion of stainless steel. The organic hydroxyacid may be a hydroxy acid containing 2 to 10 carbon atoms with at least one hydroxyl group and at least one carboxylic acid group, in a non-limiting example, glycolic acid. The pH of the methanolic solution may range from about 3.5 to about 8.

Pitting corrosion of stainless steel occurs in solutions of organic acid, such as tartaric acid, in an electrolyte solution with methanol. However, methanolic solutions containing at least one organic halide and at least one organic hydroxyacid and some water provide reduced pitting corrosion of stainless steel. The organic hydroxyacid may be a hydroxy acid containing 2 to 10 carbon atoms with at least one hydroxyl group and at least one carboxylic acid group, in a non-limiting example, glycolic acid. The pH of the methanolic solution may range from about 3.5 to about 8.

A self-healing coating composition for use on metals includes a polyurea, an epoxy ester unsaturated resin, a combination of amine terminated siloxane and epoxy terminated siloxane and an organoclay. The polyurea is a water-soluble, aromatic polyurea and likewise, the epoxy ester is a water-soluble, aromatic epoxy ester. The coating composition is formed in a non-volatile solvent, such as N-Methylpyrrolidone. It can be applied to a metal surface and cured at room temperature to form a coating that is resistant to corrosion. Further the coating self-heals in a manner similar to a chromate coating.

A self-healing coating composition for use on metals includes a polyurea, an epoxy ester unsaturated resin, a combination of amine terminated siloxane and epoxy terminated siloxane and an organoclay. The polyurea is a water-soluble, aromatic polyurea and likewise, the epoxy ester is a water-soluble, aromatic epoxy ester. The coating composition is formed in a non-volatile solvent, such as N-Methylpyrrolidone. It can be applied to a metal surface and cured at room temperature to form a coating that is resistant to corrosion. Further the coating self-heals in a manner similar to a chromate coating.

Methods of employing corrosion inhibitors with oxidizing and/or non-oxidizing biocides, such as peroxycarboxylic acids, to provide corrosion protected compositions are disclosed. Various corrosion inhibitors further provide biocidal efficacy in addition to the corrosion protection providing further benefits for application of use. Methods of employing corrosion protected biocide compositions, such as peroxycarboxylic acid compositions, for corrosion protection are particularly well suited for treating fluids intended to flow through pipes, namely in the energy industry, water and paper industries, etc. Methods providing suitable corrosion protection in comparison to untreated systems and corrosion protected systems using conventional corrosion inhibitors, such as quaternary amines and imidazolines commonly used in the industry, are disclosed.

Methods of employing corrosion inhibitors with oxidizing and/or non-oxidizing biocides, such as peroxycarboxylic acids, to provide corrosion protected compositions are disclosed. Various corrosion inhibitors further provide biocidal efficacy in addition to the corrosion protection providing further benefits for application of use. Methods of employing corrosion protected biocide compositions, such as peroxycarboxylic acid compositions, for corrosion protection are particularly well suited for treating fluids intended to flow through pipes, namely in the energy industry, water and paper industries, etc. Methods providing suitable corrosion protection in comparison to untreated systems and corrosion protected systems using conventional corrosion inhibitors, such as quaternary amines and imidazolines commonly used in the industry, are disclosed.

A method for constructing a micro-nano porous organic acid pretreatment layer on the metal surface and its application are provided. A pretreatment reagent used is prepared by chemically grafting organic acid with hydroxylation-rich polymer. After immersed in the pretreatment reagent for a period of time, the metal substrates are then dried and cured, and the organic acid pretreatment layer with a micro-nano porous structure and excellent adhesion is successfully formed. The present invention provides the pretreatment reagent and pretreatment process of the metal surface coating protection technology. The solvent is only pure water and realizes no organic solvation. The pretreatment layer has excellent adhesion with the metal substrate, rough and porous structure, and can be closely interlocked with the subsequent coating layer, which greatly enhances the anticorrosion performance of the whole coating system.

The invention relates to a composition comprising a) at least one N-methyl-N-acylglucamine of formula (I), wherein R.sup.1 represents a linear or branched, saturated or unsaturated hydrocarbon chain with 7 to 21 carbon atoms, one or more organic acids of formula (II) and/or the salts thereof, R.sup.2—COOM, wherein R.sup.2 represents a linear or branched alkyl group or a linear or branched mono- or poly-unsaturated alkenyl group with 5 to 29 carbon atoms, and M represents hydrogen or one or more cations, wherein the cations are present in charge-equalizing amounts, and c) one or more alkanolamines of formula (III), wherein NR.sup.1R.sup.2R.sup.3R.sup.1, R.sup.2 and R.sup.3 represent hydrogen, a linear or branched alkyl group with 1 to 4 carbon atoms, a cycloalkyl group with 5 to 7 carbon atoms, a linear or branched hydroxyalkyl group with 2 to 5 carbon atoms and 1 or 2 hydroxy groups or a hydroxyether group with 2 to 6 carbon atoms, with the provision that at least one of the groups is a hydroxyalkyl group or a hydroxyether group.

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A corrosion inhibiting composition includes a first plurality of carriers and a second plurality of carriers. The first plurality of carriers has a first carrier body which encapsulates a film-forming compound. The second plurality of carriers has a second carrier body encapsulates a corrosion inhibitor. Each of the first and second carrier bodies is formed of a degradable material. Coatings and methods for inhibiting corrosion on a metal substrate are also described herein.

A corrosion inhibiting composition includes a first plurality of carriers and a second plurality of carriers. The first plurality of carriers has a first carrier body which encapsulates a film-forming compound. The second plurality of carriers has a second carrier body encapsulates a corrosion inhibitor. Each of the first and second carrier bodies is formed of a degradable material. Coatings and methods for inhibiting corrosion on a metal substrate are also described herein.