ELECTROLUMINESCENCE OF PHOTODEGRADED POLY(P-PHENYLENEVINYLENE) DERIVATIVES BY ULTRAVIOLET-LASER LIGHT

We report the observations of electroluminescence of photodegraded pol y(p-phenylenevinylene) derivatives film which was irradiated with lase r light at a wavelength in the region of ultraviolet. EL spectral chan ge for different polymers shows different behaviour. Electroluminescen ce and photoluminescence intensities of PPV decreases rapidly and the intensities in the blue region become relatively severe without peak s hift. MEH-PPV shows the blue shift of the peak in EL spectra with negl igible intensity decrement. Spectroscopic results of the PPV film degr aded by UV light support the photodegradation occurred by chain-scissi on process.