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Studies of oxygen diffusion in poly(styrene-co-1-naphthyl methacrylate) by phosphorescence quenching

Measurements of oxygen diffusion in naphthalene-labeled polystyrene films were made at cryogenic temperatures by observations of the kinetics of quenching of naphthalene phosphorescence. Values of the diffusion coefficient D ranged from 3.3×10 -11 to 2.8×10 -7 cm 2 s -1 at -104 and +23 o C, respectively. The activation energy for diffusion was 7.1 kcal mol -1 , which is similar to that observed above room temperature. Static measurements employing the Stern-Volmer equation to determine k q gave comparable values only if k q q=k D /9