Chemical Physics Letters, Vol.513, No.1-3, 63-66, 2011
Direct observation of the intermolecular triplet-triplet energy transfer from UV-A absorber 4-tert-butyl-4'-methoxydibenzoylmethane to UV-B absorber octyl methoxycinnamate
Triplet energy transfer (TET) is an important photostabilization process for organic UV absorbers, such as 4-tert-butyl-4'-methoxydibenzoylmethane (BM-DBM) and octyl methoxycinnamate (OMC). To characterize interactions between UV absorbers as TET the interactions between BM-DBM and OMC have been studied through measurements of EPR and time-resolved phosphorescence spectra. The EPR B-min signals and the phosphorescence of OMC were observed through the selective excitation of BM-DBM at 365 nm in EtOH at 77 K. These results indicate that the intermolecular TET occurs from BM-DBM to OMC. This is the first report of the experimental evidence of the TET between the organic UV absorbers. (C) 2011 Elsevier B. V. All rights reserved.