Diphenyl carbonate
Diphenyl carbonate is the organic compound with the formula 2CO. It is classified as an acyclic carbonate ester. It is a colorless solid. It is both a monomer in combination with bisphenol A in the production of polycarbonate polymers and a product of the decomposition of polycarbonates.
Production
World production capacity of diphenyl carbonate was 254,000 tonnes in 2002, and phosgenation of phenol is the most significant route. Phosgenation of phenol can proceed under various conditions. The net reaction is as follows:The use of phosgene can be avoided by the oxidative carbonylation of phenol with carbon monoxide:
Dimethyl carbonate can also be transesterified with phenol:
The kinetics and thermodynamics of this reaction are not favorable. For example, at higher temperatures, dimethyl carbonate undesirably methylates phenol to give anisole. Despite this, diphenyl carbonate made from non-phosgene sources has become a widely used raw material for the synthesis of bisphenol-A-polycarbonate in a melt polycondensation process.