Photorefractive polymer composites using a trinitrofluorenone–C60 dyad with a conformationally flexible linker as photosensitizer

The photorefractive (PR) properties, via photoconductivity, birefringence and two-beam-coupling experiments, of a composite containing a fullerene–trinitrofluorenone (C60–TNF) dyad in which the two moieties are linked by a conformationally flexible polyether chain are reported. The PR performance of this compound as a sensitizer in polymer composites based on poly(N-vinylcarbazole) (PVK) as hole charge transporter, piperidindicyanostyrene (PDCST) as non-linear optical chromophore and butyl benzyl phthalate (BBP) as plasticizer, has been compared to those of the corresponding C60 and TNF derivatives. Results show that the linkage of C60 and TNF leads to an improvement in the photoconductivity of the composite leading to an increase of the PR speed.