4290
Macromolecules 1992,25, 4290-4296
Considerations for Raman Spectroscopic Determination of Polyene Length Distribution in Degraded Poly(viny1 chloride) Bert J. Kip,*JSjef M. van Asken3 Robert J. Meier,+ Kenneth P. J. Williams,$and Donald L. Gerrardg DSM Research, P.O. Box 18, 6160 M D Geleen, The Netherlands, L V M , H. Hartlaan, 3980 Tessenderlo, Belgium, and BP Research Centre, Chertsey Road, Sunbury-on-Thames, Middlesex TW16 7LN, U.K. Received September 25, 1991; Revised Manuscript Received March 25, 1992
ABSTRACT: Practicalcomplications in the quantitative Raman spectroscopic determination of the polyene sequence length distribution in degraded poly(viny1chloride) samples were found. If samples are measured directly, i.e. without dissolving them, the distribution of polyenes changes during the Raman experiment if power densities above 20 W/mm2are used. Lower power densities or short exposure times (
