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bisphenol A BPA

(Click here for a model of a molecule of bisphenol A BPA)

News about  bisphenol A BPA



BPA stands for bisphenol A. It is an organic chemical which is the essential basic building block (intermediate) for polycarbonate plastic and epoxy resins. Around two thirds of all BPA is used to produce polycarbonate plastic, which is a highly durable, versatile, heat and shatter-resistant and transparent plastic found in a wide range of essential consumer applications.

Bisphenol A was first synthesized by the Russian chemist A.P. Dianin in 1891. This compound is synthesized by the condensation of acetone (hence the suffix A in the name) with two equivalents of phenol. The reaction is catalyzed by a strong acid, such as hydrogen chloride (HCl) or a sulfonated polystyrene resin. Industrially, a large excess of phenol is used to ensure full condensation; the product mixture of the cumene process (acetone and phenol) may also be used as starting material:

A large number of ketones undergo analogous condensation reactions. Commercial production of BPA requires distillation – either extraction of BPA from many resinous byproducts under high vacuum, or solvent-based extraction using additional phenol followed by distillation.
World production capacity of this compound was 1 million tonnes in the 1980s, and more than 2.2 million tonnes in 2009. In 2003, U.S. consumption was 856,000 tonnes, 72% of which was used to make polycarbonate plastic and 21% going into epoxy resins.[In the US less than 5% of the BPA produced is used in food contact applications.

Epoxy resins containing bisphenol A are used as coatings on the inside of almost all food and beverage cans, however, due to BPA health concerns, in Japan epoxy coating was mostly replaced by PET film

BPA is also used to form epoxy resin coating of water pipes. In older buildings, such resin coatings are used to avoid a replacement of deteriorating hot and cold water pipe