Dgj. Sutherland et al., PHOTOOXIDATION OF ELECTROLUMINESCENT POLYMERS STUDIED BY CORE-LEVEL PHOTOABSORPTION SPECTROSCOPY, Applied physics letters, 68(15), 1996, pp. 2046-2048
The C 1s and O 1s core-level photoabsorption spectra of poly[2-methoxy
,5-(2'-ethyl-hexoxy)-1,4-phenylene vinylene] (MEH-PPV) before and afte
r exposure O-2 and broadband visible light were recorded to determine
the degradation pathway for this polymer. The change in the O 1s spect
ra as a function of exposure demonstrates that the O adds to the polym
er chain to form a carbonyl group. Exposure to only O-2 or only light
causes no change in the C 1s or O 1s spectra. In the C 1s spectra, the
change in the dependence on the photon angle of incidence after expos
ure demonstrates that O attacks the polymer at the double bond in the
vinyl group thereby altering the extended conjugation of the polymer.
(C) 1996 American Institute of Physics.