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phthalic acid Line breaks: phthal¦ic acid
Pronunciation: /ˈ(f)θalɪk/

Definition of phthalic acid in English:


A crystalline acid derived from benzene, with two carboxylic acid groups attached to the benzene ring.
  • Chemical formula: C6H4(COOH)2; three isomers
Example sentences
  • Alkyd is produced by condensation reactions between polycarboxylic acids and polyhydric alcohols - often phthalic acid or anhydride and glycerol.
  • A wide range of uses has been found for various phthalic acid esters, with the largest portion of these esters being used as plasticizing agents for polyvinyl chloride products.
  • Capillaries were immersed in phthalic acid, which has an index of refraction that effectively eliminates optical refraction at the outer wall.


Mid 19th century: phthalic, shortening of naphthalic (see naphthalene).

Definition of phthalic acid in:
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