Photochromic Behavior in the Molecular Glass of 4,4′,4″-Tris(3-methylphenylphenylamino)triphenylamine

For the purpose of gaining information on the microstructure of molecular glasses, photochromic behavior of 4-dimethylaminoazobenzene (DAAB) in the molecular glass of 4,4′,4″-tris(3-methylphenylphenylamino)triphenylamine (m-MTDATA) was studied in comparison with that in a polystyrene matrix and in a benzene solution. The results strongly suggest that the local free volume in the molecular glass of m-MTDATA is smaller than that in the polystyrene glass.