Intramolecular Triplet Energy Transfer in Poly(1-vinylnaphthalene)

Poly(1-vinylnaphthalene) in a rigid glass at 77°K exhibits a delayed fluorescence due to triplet–triplet annihilation following intramolecular triplet energy transfer through the naphthalene chromophores. Delayed fluorescence does not appear in the spectrum of 1-ethylnaphthalene at equivalent concentrations, about 10−3M. Delayed emission from the polymer but not from 1-ethylnaphthalene is quenched by piperylene. End groups are more important than chain length in the control of triplet migration in the homopolymer; experiments with 1-vinylnaphthalene-methyl methacrylate copolymers, however, indicate that some minimum chain length is required for efficient annihilation.