Editing Polycarbonate (section)

==Structure==
[[File:DINWOM10.png|thumb|left|Structure of dicarbonate (PhOC(O)OC<sub>6</sub>H<sub>4</sub> )<sub>2</sub>CMe<sub>2</sub>  derived from bis(phenol-A) and two equivalents of phenol.<ref name=Perez>{{cite journal|doi=10.1021/ma00167a014|title=Crystalline features of 4,4'-isopropylidenediphenylbis(phenyl carbonate) and conformational analysis of the polycarbonate of 2,2-bis(4-hydroxyphenyl)propane|journal=Macromolecules|volume=20|issue=1|pages=68–77|year=1987|last1=Perez|first1=Serge|last2=Scaringe|first2=Raymond P.|bibcode=1987MaMol..20...68P}}</ref>  This molecule reflects a subunit of a typical polycarbonate derived from bis(phenol-A).]]
Carbonate esters have planar OC(OC)<sub>2</sub> cores, which confer rigidity.  The unique O=C bond is short (1.173 Å in the depicted example), while the C-O bonds are more ether-like (the bond distances of 1.326 Å for the example depicted). Polycarbonates received their name because they are [[polymers]] containing [[carbonate ester|carbonate group]]s (−O−(C=O)−O−). A balance of useful features, including temperature resistance, impact resistance and optical properties, positions polycarbonates between [[commodity plastics]] and [[engineering plastic]]s.