Time behaviors of photoluminescence (PL) intensity have been investigated under vacuum for poly(2-methoxy-5-(2'-ethyl-hexyloxy)-1,4-phenylene-vinylene) (MEH-PPV) polymers and have been compared with those for MEH-PPV with a small degree of crosslink in the polymer structure. The samples show photoinduced PL increasing or decreasing behaviors depending on the film thickness and the existence of crosslink in the network structure. The lowered PL intensity is partially recovered to a certain level and the increased PL intensity is even more enhanced while the illuminated samples are kept under vacuum at room temperature for several hours after turning off the irradiation of the excitation light. There is a close relationship between the time behaviours of PL and the shape of its spectrum. It can be suggested that these anomalous phenomena can be attributed to the chemical structural variation due to the chain shortening during illumination by the excitation light and the crosslinking in the network structure.
|Journal||Journal of the Korean Physical Society|
|Publication status||Published - 2004 Dec|
- Network structure
- Phenylenevinylene polymer
ASJC Scopus subject areas
- Physics and Astronomy(all)