Ultraviolet photophysical studies

Photophysical Studies of Ultraviolet Stabilizers, Particularly in the 2-Hydroxyphenyl Benzotriazole Class... 

The U.S. - Australia Symposium on Radiation Effects on Polymeric Materials contained research presentations on fundamental radiation chemistry and physics as well as on technological applications of polymer irradiation. This paper represents a hybrid contribution of these two areas, examining a field of extensive technological importance. Spin casting of radiation sensitive polymer resists for microelectronic fabrication was studied using photophysical techniques that are sensitive to the fundamental radiation response in the ultraviolet range. 

The photodegradation of polymers has been studied mainly from the practical angle, since polymers have many commercial uses. Various kinds of stabilizers, such as ultraviolet absorbers and antioxidants, have been developed but the mechanism of stabilization has not yet been completely clarified from the point of view of the photophysical and photochemical processes involved in polymer systems. 

Hrdlovic [17] has reviewed the application of Fourier transform ultraviolet and fluorescence techniques to a study of photochemical reactions and photophysical processes in polymers. 

Ultraviolet and visible light absorption spectroscopy can be used to identify chromophores (e.g. benzene rings and carbonyl groups) and to determine the lengths of sequences of conjugated multiple bonds in polymers. It also can be used to analyse polymers for the presence of additives such as antioxidants or for detection of residual monomer(s). Additionally, fluorescence and phosphorescence techniques are important in studies of polymer photophysics. 

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