Deviations of the glass transition temperature in amorphous conjugated polymer thin films.

The deviations of the glass transition temperature (Te) in thin films of an amorphous conjugated polymer poly(9,9-dioctylfluorene-co-/V-(4-butylphenyl)diphenylamine) (TFB) are reported. Monotonie and nonmono-tonic rs deviations are observed in TFB thin films supported on Si-SiOx and poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate) (PEDOTtPSS), respectively. A three-layer model is developed to fit both monotonie and nonmonotonic Tg deviations in these films. A 5-nm PEDOT:PSS capping layer was not found to be effective to remove the free-surface effect in Si-SiOx supported TFB films. [ABSTRACT FROM AUTHOR]