Self-quenching of the triplet state of a semifluorinated polyimide in solution

Triplet lifetimes of semifluorinated polyimides and related model compounds were determined using laser hash photolysis. It was found that the triplet lifetimes of polyimides in relatively good solvents were about 10 times le ss than those of N-arylphthalimide models. The significant reduction in the tripler lifetimes of the polymers is attributed to an intrachain self-quen ching process of the triplet state via interaction between main chain chrom ophores. Triplet lifetimes of one of the semifluorinated polyimides polymer s in a variety of solvents of varying solvent powers were measured. In rela tively poor solvents, more than a 10-fold reduction in the triplet lifetime s was observed compared to the lifetimes in relatively good solvents, sugge sting that intrachain self-quenching readily occurs due to enhanced coiling of the polymer in the poor solvents, (C) 2000 Elsevier Science S.A. All ri ghts reserved.