Patent ID: 6541264
Filing Date: 2003-04-01
Classification: G01N

Abstract:
A method of characterizing an aromatic polycarbonate prepared by a â€œmeltâ€  polymerization, said method comprising:providing at least one analytical sample comprising an aromatic polycarbonate; irradiating the analytical sample at a first wavelength range to excite fluorescence; detecting fluorescence emission intensities from the analytical sample at a second wavelength range and a third wavelength range, the second wavelength range and the third wavelength ranges being separated from each other and from the first wavelength range by at least five nanometers; and characterizing the polycarbonate comprising the analytical sample based on the fluorescence emission intensities at the second and third wavelength ranges, said characterizing comprising determining a polycarbonate product selectivity for the â€œmeltâ€  polymerization, wherein the product selectivity for the â€œmeltâ€  polymerization is expressed as the ratio of the polycarbonate number average molecular weight to Fries product content.