The following is an abstract for the selected article. A PDF download of the full text of this article is available here. Members may download full texts at no charge. Non-members may be charged a small fee for certain articles.
Laser-Induced Breakdown Spectroscopy for Analysis of Chemically Etched Polytetrafluoroethylene
Volume 62, Number 7 (July 2008) Page 773-777
Rusak, David A.; Weaver, Kira D.; Taroli, Brett L.
Laser-induced breakdown spectroscopy (LIBS) is used to analyze chemically etched polytetrafluoroethylene (PTFE). The elements O, F, H, and Na are determined qualitatively in the depth dimension. It is shown that O, H, and Na signals are greatest at the surface and decrease as the laser burrows through the etched layer into the bulk. In contrast, the fluorine signal is a minimum at the surface and increases with depth. The average ablation rate for PTFE under the experimental conditions is found to be 1.9 μm per pulse. Using this value, the depth of the etched layer is determined to be 8 μm. A calibration curve produced by analysis of different polymers gives mole fractions of O, F, and H at the surface of the etched PTFE of 0.2, 0.3, and 0.1, respectively.