Premium
Quantitative use of ultraviolet spectroscopy to calculate the effective irradiation dosage during weathering
Author(s) -
Croll Stuart,
Skaja Allen
Publication year - 2002
Publication title -
macromolecular symposia
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.257
H-Index - 76
eISSN - 1521-3900
pISSN - 1022-1360
DOI - 10.1002/1521-3900(200209)187:1<861::aid-masy861>3.0.co;2-1
Subject(s) - absorbance , quantum yield , ultraviolet , absorption (acoustics) , materials science , coating , excited state , photochemistry , chemistry , analytical chemistry (journal) , optics , optoelectronics , atomic physics , nanotechnology , physics , composite material , organic chemistry , fluorescence
The ultraviolet absorbance of a urethane coating showed typical yellowing that increased with exposure period. An effective dosage was calculated from the solar spectrum, the quantum yield for the degradation process and the ultraviolet absorption. Assuming a constant quantum yield, there is a clear acceleration of the absorption of damaging radiation because the ultraviolet absorption increases with exposure. This non‐linear relationship offers possibilities on how to estimate a service lifetime. In addition, the yellowing can be analyzed as an “Urbach” tail which is usually attributed to structural disorder that introduces energy levels between the ground and excited electronic states.