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William E. Wallace, Daniel A. Fischer, K Efimenko, Wen-Li Wu, Jan Genzer
Abstract
In this work we show how carbon near-edge X-ray absorption fine structure (NEXAFS) can be applied to detect both surface and bulk segmental relaxation in uniaxially deformed polystyrene samples. We demonstrate that by simultaneously monitoring the partial electron yield (PEY, kinetic energy > 150 eV) and the fluorescence yield (FY, carbon Ka 277 eV) NEXAFS signals, with probing depths of approximately 2 and 200 nm, respectively, one can, in a single experiment, examine segmental motion throughout a polymer sample. Using this methodology, chain relaxation is found to occur almost 50% faster at the surface than in the bulk.
Wallace, W.
, Fischer, D.
, Efimenko, K.
, Wu, W.
and Genzer, J.
(2001),
Polymer Chain Relaxation: Surface Outpaces Bulk, Macromolecules, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=851810
(Accessed October 13, 2025)