Diphenyl carbonate is the

organic compound In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen or carbon-carbon bonds. Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. Th ...

with the formula (C₆H₅O)₂CO. It is classified as an acyclic

carbonate ester In organic chemistry, a carbonate ester (organic carbonate or organocarbonate) is an ester of carbonic acid. This functional group consists of a carbonyl group flanked by two alkoxy groups. The general structure of these carbonates is and the ...

. It is a colorless solid. It is both a

monomer In chemistry, a monomer ( ; '' mono-'', "one" + '' -mer'', "part") is a molecule that can react together with other monomer molecules to form a larger polymer chain or three-dimensional network in a process called polymerization. Classification ...

in combination with

bisphenol A Bisphenol A (BPA) is a chemical compound primarily used in the manufacturing of various plastics. It is a colourless solid which is soluble in most common organic solvents, but has very poor solubility in water. BPA is produced on an industrial ...

in the production of

polycarbonate Polycarbonates (PC) are a group of thermoplastic polymers containing carbonate groups in their chemical structures. Polycarbonates used in engineering are strong, tough materials, and some grades are optically transparent. They are easily work ...

polymer A polymer (; Greek '' poly-'', "many" + '' -mer'', "part") is a substance or material consisting of very large molecules called macromolecules, composed of many repeating subunits. Due to their broad spectrum of properties, both synthetic a ...

s 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 Phenol (also called carbolic acid) is an aromatic organic compound with the molecular formula . It is a white crystalline solid that is volatile. The molecule consists of a phenyl group () bonded to a hydroxy group (). Mildly acidic, it r ...

is the most significant route. Phosgenation of

can proceed under various conditions. The net reaction is as follows: : 2 PhOH + COCl₂ → PhOCO₂Ph + 2 HCl The use of

phosgene Phosgene is the organic chemical compound with the formula COCl2. It is a toxic, colorless gas; in low concentrations, its musty odor resembles that of freshly cut hay or grass. Phosgene is a valued and important industrial building block, esp ...

can be avoided by the oxidative

carbonylation Carbonylation refers to reactions that introduce carbon monoxide into organic and inorganic substrates. Carbon monoxide is abundantly available and conveniently reactive, so it is widely used as a reactant in industrial chemistry. The term carbon ...

of phenol with

carbon monoxide Carbon monoxide ( chemical formula CO) is a colorless, poisonous, odorless, tasteless, flammable gas that is slightly less dense than air. Carbon monoxide consists of one carbon atom and one oxygen atom connected by a triple bond. It is the simpl ...

: : 2 PhOH + CO + → PhOCO₂Ph + H₂O Dimethyl carbonate can also be transesterified with phenol: : CH₃OCO₂CH₃ + 2 PhOH → PhOCO₂Ph + 2 MeOH The kinetics and thermodynamics of this reaction are not favorable. For example, at higher temperatures, dimethyl carbonate undesirably methylates phenol to give

anisole Anisole, or methoxybenzene, is an organic compound with the formula CH3OC6H5. It is a colorless liquid with a smell reminiscent of anise seed, and in fact many of its derivatives are found in natural and artificial fragrances. The compound i ...

. Despite this, diphenyl carbonate made from non-phosgene sources has become a widely used raw material for the synthesis of

bisphenol-A Bisphenol A (BPA) is a chemical compound primarily used in the manufacturing of various plastics. It is a colourless solid which is soluble in most common organic solvents, but has very poor solubility in water. BPA is produced on an industrial s ...

-polycarbonate in a melt polycondensation process.

Applications

Polycarbonates can be prepared by transesterifying diphenyl carbonate with

. Phenol is a co-product. These polycarbonates may be recycled by reversing the process: transesterifying the polycarbonate with phenol to yield diphenyl carbonate and bisphenol A.

References

{{DEFAULTSORT:Diphenyl Carbonate Monomers Carbonate esters