In this work we investigate on the local free volume of a crosslinked polystyrene by studying the steady-state fluorescence anisotropy of three probes with different sizes and shape, embedded in the polymer matrix. The very low values measured for the steady-state fluorescence anisotropy show that the molecules can perform ample movements during their excited-state lifetimes (typically few nanoseconds). Moreover, anisotropy values decrease with the size of the probe. Results were interpreted in terms of Saupe order parameters and the wobbling-in-cone model. © 1999 Elsevier Science S.A.
|Journal||Journal of Photochemistry and Photobiology A: Chemistry|
|Publication status||Published - 1 Jan 1999|