Publications [#233689] of Richard A. Palmer

Journal Articles

  1. Wang, H; Palmer, RA; Manning, CJ, "Study of Impulse Polymer Rheo-Optics by Step-Scan FT-IR Time-Resolved Spectroscopy S2FT-IR TRS", Appl. Spectrosc., 1997, 51(8), 1245, SAGE Publications [Gateway.cgi], [doi].
    (last updated on 2024/07/16)

    Abstract:
    The applicability of step-scan impulse/response FT-IR spectroscopy to the rheo-optical study of polymer films is demonstrated by spectral measurements with isotactic polypropylene. A novel piezoelectrically driven microrheometer is employed to apply repetitive impulses to a polymer sample while time-domain spectra are recorded by step-scan FT-IR spectroscopy. The traditional advantages of Fourier transform spectroscopy are retained while providing a second multiplex advantage for the characterization of the time-dependence of the sample response. Reproducible results, consistent with the frequency-domain literature data and having good signal-to-noise ratio, are obtained. The spectral changes due to molecular reorientation are found to be essentially as fast as the mechanical stretching, also consistent with frequency-domain results. To our knowledge, this is the first reported step-scan FT-IR time-domain rheo-optical measurement. This technique appears to be applicable to a variety of polymer samples. The advantages of time-domain measurements over frequency-domain measurements are briefly discussed.