Photo-aging of polycarbonate: The effects of selected variables on degradation pathways.

Films of bisphenol A polycarbonate have been exposed to photo- aging at 25C with the following variables controlled: l) minimum wavelength of light; 2) O2 or N2 atmosphere; 3) presence or absence of humidity; 4) degree of prior hydrolysis. Changes in the samples have been followed using ultraviolet and infrared spectroscopy as well as gel permeation and liquid chromatography. Observed changes include crosslinking, chain scission and further reactions of scission fragments.