Terephthalic acid

Terephthalic acid is the organic compound with formula C₆H₄(CO₂H)₂. This white solid is a commodity chemical, used principally as a precursor to the polyester PET, used to make clothing and plastic bottles. Several million tonnes are produced annually.

History

The importance of the terephthalic acid was realized after World War II. The first companies to commercialize the use of the fibers made from polyethylene terephthalate were Imperial Chemical Industries in the UK in 1949 and DuPont in the US in 1953. The fibers were made from dimethyl terephthalate by transesterification with ethylene glycol. Terephthalic acid was produced by oxidation of p-xylene with dilute nitric acid. This type of oxidation involved the use of air in the initial oxidation step to minimize the consumption of nitric acid and difficulty in purification. Growth in the textile industry led to increase in demand of TPA. In the 1960s, all the terephthalic acid produced was converted to its dimethyl ester, since TPA was infusible and difficult to purify. Presently TPA is manufactured by oxidation of p-xylene.

Terephthalic acid (data page)

This page provides supplementary chemical data on Terephthalic acid, the organic compound and one of three isomeric phthalic acids, all with formula C₆H₄(CO₂H)₂.

Material Safety Data Sheet

The handling of this chemical may require notable safety precautions, which are set forth on the Material Safety Datasheet (MSDS) for it.SIRI

Structure and properties

Thermodynamic properties

Spectral data

Notes and references