isophthalic acid

chemical compound

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June 29, 2026

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Isophthalic acid is a crystalline diacid with the chemical formula C₆H₄(COOH)₂. It is an isomer of phthalic acid and is typically produced by oxidizing meta-xylene. Isophthalic acid is utilized in the creation of synthetic resins and esters, which find applications as plasticizers.1

It is also known as meta-benzene-dicarboxylic acid and is one of three important aromatic dicarboxylic acids, alongside phthalic acid (ortho isomer) and terephthalic acid (para isomer). Aromatic carboxylic acids, like isophthalic acid, exhibit acidic properties and can undergo electrophilic substitution reactions, though the carboxyl group is deactivating and meta-directing.2

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carboxylic acid
Aromatic acids
…dicarboxylic acids are called phthalic, isophthalic, and terephthalic acid, for the ortho, meta, and para isomers, respectively. Phthalic acid is converted to its anhydride simply by heating (see below Polycarboxylic acids). Phthalic anhydride is used to make polymeric resins called alkyd resins, which are used as coatings, especially for
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…dicarboxylic acids are called phthalic, isophthalic, and terephthalic acid, for the ortho, meta, and para isomers, respectively. Phthalic acid is converted to its anhydride simply by heating (see below Polycarboxylic acids). Phthalic anhydride is used to make polymeric resins called alkyd resins, which are used as coatings, especially for
Read More