Synchrotron powered FT-IR microspectroscopic incremental probing of photochemically degraded polymer films
- Microbeam Molecular Spectroscopy Laboratory, Kansas State University, Shellenberger Hall, Manhattan, Kansas, 66506 (United States)
- Ford Motor Co., Scientific Research Laboratory, PO Box 2053, MD 061, Dearborn, Michigan 48121; Los Alamos National Lab, CST-4, Mail Stop J586, Los Alamos, New Mexico 87545 (United States)
An acrylic polymer automotive coating that had been subjected to Florida sun for 3 years was subsequently exposed to accelerated photochemical attack with Xenon lamps. Microtomed 6 {mu}m-thick sections of the photochemically degraded polymer films were mounted between two 13thinspmmthinspdiameter{times}2thinspmmthinspthick barium fluoride disks in a compression cell. With dual apertures 6 {mu}m wide and 36 {mu}m long, a line mapping procedure was performed by stepping the motorized stage in 5 {mu}m increments. The chemical composition was mapped from the outermost edge through the degraded and washed out area into the pristine part of the clear coat, the base coat, and finally the primer. The results of incremental probing of the exposed acrylic polymer coating was compared to a retained specimen of the same material that had been protected from exposure to ultraviolet radiation. Previous attempts with photoacoustic infrared spectroscopy had established the destruction of some absorption bands and the appearance of new broad bands of oxidation products. The depth of the photochemical action was revealed by transmission probing as described here including 1 {mu}m increment line mapping across the clear coat. Interdiffusion of adjacent clear and base coats was also evident. Other polymers subjected to impingement of O{sup +4} at different levels of flux showed oxidation by ATR microspectroscopy of the exposed surface in comparison to spectra obtained by the same means from the unexposed back side of the 0.25 in-thick specimen of polypropylene. {copyright} {ital 1998 American Institute of Physics.}
- Research Organization:
- Brookhaven National Lab. (BNL), Upton, NY (United States)
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- AC02-76CH00016
- OSTI ID:
- 641493
- Report Number(s):
- CONF-970812-; ISSN 0094-243X; TRN: 9817M0020
- Journal Information:
- AIP Conference Proceedings, Vol. 430, Issue 1; Conference: 11. international conference on Fourier transform spectroscopy, Athens, GA (United States), 10-15 Aug 1997; Other Information: PBD: Jun 1998
- Country of Publication:
- United States
- Language:
- English
Similar Records
Infrared microspectroscopic study of the thermo-oxidative degradation of hydroxy-terminated polybutadiene/isophorone diisocyanate polyurethane rubber
Metabolically deuterated species determined in rat cerebella by FT-IR microspectroscopy as a novel probe of brain metabolism