Photosensitized production of singlet molecular oxygen (/sup 1/. delta. /sub g/O/sub 2/) in a solid organic polymer glass: a direct time-resolved study

Journal Article · Wed Jul 22 00:00:00 EDT 1987 · J. Am. Chem. Soc.; (United States)

DOI:https://doi.org/10.1021/ja00249a062· OSTI ID:6334571

Ogilby, P R; Iu, K; Clough, R L

The photosensitized production of singlet molecular oxygen (/sup 1/..delta../sub g/O/sub 2/) has long been a subject of scientific study. Recently, direct evidence for the presence of /sup 1/..delta../sub g/O/sub 2/ in thin (10-30 ..mu..m) polymer films was obtained by Byteva et al. who detected /sup 1/..delta../sub g/O/sub 2/ phosphorescence (/sup 3/..sigma../sub g//sup -/O/sub 2/ reverse arrow /sup 1/..delta../sub g/O/sub 2/: 1270 nm) in a steady-state photosensitized experiment. In a time-resolved study, /sup 1/..delta../sub g/O/sub 2/ has also been observed in a heterogeneous ionomer system (Nafion powders) in which the /sup 1/..delta../sub g/O/sub 2/ sensitizer was apparently located at the surface of solvent filled or dessicated cavities. They now report that /sup 1/..delta../sub g/O/sub 2/ phosphorescence can be detected in a time-resolved photosensitized experiment from a homogeneous, solid polymethylmethacrylate (PMMA) glass. As in the solution phase, they expect this technique will become an indispensable tool in studies of /sup 1/..delta../sub g/O/sub 2/ photophysics and photochemistry. In particular, the role of /sup 1/..delta../sub g/O/sub 2/ in the photooxidation and photodegradation of solid polymers has been a focus of debate. Since they directly monitor molecular oxygen, this experimental approach also provides a unique method to accurately quantify oxygen diffusion in a polymer.

• Research Organization: Univ. of New Mexico, Albuquerque
• DOE Contract Number: AC04-76DP00789
• OSTI ID: 6334571
• Journal Information: J. Am. Chem. Soc.; (United States), Journal Name: J. Am. Chem. Soc.; (United States) Vol. 109:15; ISSN JACSA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400500* -- Photochemistry
CHEMICAL REACTIONS
CHEMISTRY
DATA
ELECTRONIC STRUCTURE
ELEMENTS
ESTERS
EXPERIMENTAL DATA
GLASS
INFORMATION
NONMETALS
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC POLYMERS
OXYGEN
PHOTOCHEMICAL REACTIONS
PHOTOCHEMISTRY
PHOTOSENSITIVITY
PMMA
POLYACRYLATES
POLYMERS
POLYVINYLS
SENSITIVITY
TIME DEPENDENCE