Characterization of PMDI/HOPG Interfaces by SERS Using a Silver Overlayer Configuration.

摘要

Surface-enhanced Raman scattering (SERS) was used for characterization of model fiber/polyimide interfaces. Pyromellitic diimide (PMDI) was used as a model polyimide while highly oriented pyrolytic graphite (HOPG) was viewed as a model graphite fiber. Samples for SERS were prepared by depositing films of PMDI onto HOPG and then depositing silver island films on top of the PMDI. When the PMDI films were relatively thick (85 A), the SERS spectra were similar to normal Raman spectra of bulk PMDI. These spectra were characterized by the imide bands near 1775, 1748, 1368, and 659 1/cm and by the benzene ring bands near 1633, 1200, 762, 578, and 520 1/cm, respectively. Keywords: PMDI/HOPG interfaces, SERS, Silver overlayer configuration, Plastics, Adsorption, Surface chemistry, Spectroscopy, DD Form 1473. (JG)