The effect of photo-oxidation on the photo-conductivity of isolated polyphenylenevinylene chains

The photo-conductivity of isolated poly(2-methoxy-5-[2′-ethylexyloxy]-1,4-phenylenevinylene), MEH-PPV, chains in dilute solution, as measured by time-resolved microwave conductivity, decreases markedly on photo-oxidation. The optical absorption and emission characteristics are much less sensitive to photo-oxidation. Comparison with results for PPV derivatives with broken conjugation indicate a quantum yield for photo-oxidative defects in an air saturated solution of ca.