Phthalic Acid

What Does Phthalic Acid Mean?

Phthalic acid (PA) is chemical substance that is an aromatic dicarboxylic acid, with the chemical formula C₆H₄(COOH)₂. It is used primarily to make corrosion inhibitors that are applied to metal substrate surfaces.

Corrosionpedia Explains Phthalic Acid

Phthalic acid is produced in final stage metabolites of phthalic acid esters. It interacts with magnesium oxide films to generate the following inhibitor mechanisms on a substrate metal to be protected:

• Absorption by the process of chemisorption, forming a protective film in conjunction with metallic ions
• Increased resistance of a metal to environmental factors by self-propagation of independent protective oxides
• Reaction with a potentially corrosive substance in the presence of water

Care should be taken when handling phthalic acid as it is highly corrosive and may cause irritation to human skin, eyes and respiratory tracts.