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Spectral quality enhancement as an aid to polymer characterisation
Author(s) -
Maddams William F.
Publication year - 1986
Publication title -
makromolekulare chemie. macromolecular symposia
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.257
H-Index - 76
eISSN - 1521-3900
pISSN - 0258-0322
DOI - 10.1002/masy.19860050105
Subject(s) - fourier transform , spectrometer , polymer , resolution (logic) , infrared , curve fitting , maximum entropy spectral estimation , fourier transform infrared spectroscopy , materials science , spectral resolution , infrared spectroscopy , limit (mathematics) , spectral line , second derivative , computational physics , optics , principle of maximum entropy , physics , computer science , nuclear magnetic resonance , mathematics , mathematical analysis , statistics , quantum mechanics , astronomy , artificial intelligence
The limit to the information on the microstructure of polymers that may be obtained from their vibrational spectra is often set by overlapping bands, markedly broader than the spectrometer resolution. Following the initial pioneering work of Pohl and Hummel, using a simple curve fitting technique, mathematical methods of spectral quality enhancement have progressed very considerably. These methods are reviewed critically and new results are presented. The desirability of imposing some parameter constraints in curve fitting is demonstrated, and this has led to the development of methods for peak narrowing, as an aid to peak finding. The two important approaches, derivative spectroscopy and Fourier selfdeconvolution (FSD), are discussed in terms of their application to the complex of overlapping bands in the v (C‐Cl) region of the infrared spectrum of poly(vinyl chloride). A development of the FSD method termed Fourier band isolation, is described and preliminary results indicate that it has considerable promise. The maximum entropy method is discussed briefly.