POSITRON-ANNIHILATION DETECTION OF ULTRA-VIOLET LIGHT-INDUCED DAMAGE IN CONJUGATED POLYMERS

The Doppler-broadened positron annihilation radiation (DBAR) lineshape S-parameter, and the optical absorption spectra were measured during Ultra-violet (UV) exposure to a polydiacetylene (p-4BCMU) which degrad ed, and a polyquinoline which did not degrade, when exposed to UV ligh t. The S-parameter of p-4BCMU increased during photodegradation and co rrelated closely to the change in optical absorption spectra. The S-pa rameter of a polyquinoline remained unchanged.