Authors Tsuwi, J. ; Kremer, F. ; Appelhans, D. ; Zschoche, St. ; Friedel, P.
Title Molecular dynamics in poly(ethene-alt-N-alkylmaleimide) copolymers as studied by Broadband Dielectric Spectroscopy
Date 09.12.2004
Number 12179
Abstract Broadband dielectric spectroscopy has been used to analyze the molecular dynamics in aset of nine poly(ethene-<I>alt</I>-<I>N</I>-alkylmaleimide)s. The polymers were studied in the frequency range from0.1 Hz to 10 MHz and at temperatures between 120 and 500 K. The alternating maleimide copolymerspossess alkyl side chains varying in length from methyl to octadecyl. Four relaxation processes areobserved: (i) a (secondary) <IMG SRC="/images/gifchars/beta2.gif" BORDER=0 ALIGN="middle">-relaxation corresponding to librational fluctuations of the terminal end groupof the alkyl side chain, (ii) the <IMG SRC="/images/gifchars/alpha.gif" BORDER=0>'-relaxation being assigned to a relaxation of the side chain, (iii) thedynamic glass transition (<IMG SRC="/images/gifchars/alpha.gif" BORDER=0>-relaxation), being designated to motions of the succinimide ring, and (iv) the<IMG SRC="/images/gifchars/alpha.gif" BORDER=0><SUB>s</SUB>-relaxation reflecting cooperative fluctuations of an ensemble of about 2-3 maleimide rings in anunderlying helical superstructure. This model is supported by calorimetric measurements and publishednuclear magnetic resonance data.
Publisher Macromolecules
Citation Macromolecules 37 (2004) 6050-6054

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