skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Spectromicroscopy of poly(ethylene terephthalate): Comparison of spectra and radiation damage rates in X-ray absorption and electron energy loss

Journal Article · · Journal of Physical Chemistry B: Materials, Surfaces, Interfaces, amp Biophysical
DOI:https://doi.org/10.1021/jp9622748· OSTI ID:502017
 [1]; ;  [2]
  1. Dow Chemical, Freeport, TX (United States)
  2. McMaster Univ., Hamilton, Ontario (Canada); and others

The C 1s and O 1s X-ray absorption spectra of poly(ethylene terephthalate) (PET) have been recorded using transmission, fluorescence, and electron yield detection. The corresponding electron energy loss spectra (EELS) have been recorded in a scanning transmission electron microscope. These results are compared to the C 1s and O 1s spectra of gas phase 1,4-dimethyl terephthalate (the monomer of PET) recorded using EELS. The comparison of monomer and polymer materials in different phases and with different techniques has aided the understanding of the relative strengths and limitations of each technique as well as assisting the spectral interpretation. Good agreement is found in the overall shape and the energies of the spectral features. Relatively minor differences in intensities can be understood in terms of the properties of the individual spectroscopic techniques. The critical dose for radiation damage by 100 keV electrons incident on PET at 100 K is found to be (1.45{+-}0.15)x10{sup 3} eV nm{sup -3}. In contrast, the critical dose for radiation damage by 302 eV X-rays incident on PET at 300 K is (1.2{+-}0.6)x10{sup 4} eV nm{sup -3}. A figure of merit involving the product of critical energy dose and spectral efficiency (as expressed by the appropriate G value) is developed. 59 refs., 5 figs., 4 tabs.

OSTI ID:
502017
Journal Information:
Journal of Physical Chemistry B: Materials, Surfaces, Interfaces, amp Biophysical, Vol. 101, Issue 11; Other Information: PBD: 13 Mar 1997
Country of Publication:
United States
Language:
English