Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
9817689 | Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms | 2005 | 8 Pages |
Abstract
Poly(methyl methacrylate) (PMMA), known as a radiation-degrading polymer, showed mechanically hardening behavior under a high-fluence electron irradiation. When the electron fluence was less than 1Â ÃÂ 1015Â cmâ2, PMMA showed normal degrading behavior. However, at electron fluence higher than 1Â ÃÂ 1017Â cmâ2, the mechanical properties of the irradiated PMMA were tremendously improved. Bulk plate PMMA samples and an electron energy of 60Â keV were employed in the irradiation experiments. The surface hardness of the irradiated PMMA increased from a pristine value of 0.29Â GPa up to 2.8Â GPa and the elastic modulus increased from 5.6Â GPa to 22.9Â GPa at an electron fluence of 7.5Â ÃÂ 1017Â cmâ2. Both Raman spectra and XPS spectra showed that the surface hardening was attributed to the transformation of polymeric materials into hydrogenated amorphous carbon under the electron irradiation. Confocal Raman spectra showed that the transformation occurred from the surface to the depth of electron range.
Keywords
Related Topics
Physical Sciences and Engineering
Materials Science
Surfaces, Coatings and Films
Authors
Sung Oh Cho, Hye Young Jun,