Copolycarbonates of phenolphthalein polycarbonates and other polycarbonates
 Novel copolycarbonates exhibiting generally improved impact resistance, clarity and flame resistance are prepared by blending a polycarbonate of a trityldiol such as phenolphthalein and a polycarbonate of another diol such as bisphenol-A under conditions of temperature and/or shear sufficient to cause reaction of the polycarbonates. 
The Dow Chemical Company
C
C08L
inventional
Joseph B. Christian A.
Byrne Weber