Regensburg 2004 – wissenschaftliches Programm

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CPP: Chemische Physik und Polymerphysik

CPP 7: Physics of Polymers I

CPP 7.6: Vortrag

Montag, 8. März 2004, 15:15–15:30, H 37

Molecular dynamics of alternating maleimide copolymers as studied by Broadband Dielectric Spectroscopy — •Julius Tsuwi¹, Dietmar Appelhans², and Friedrich Kremer¹ — ¹Institute for Experimental Physics I, University of Leipzig, Linnestrasse 5, 04103, Leipzig, Germany — ²Institute for Polymer Research Dresden, Hohestrasse 6, 01069 Dresden, Germany

Dielectric study on the molecular dynamics in a set of poly(alkene-alt-N-(perfluoro-)alkylmaleimide) copolymers is presented. The polymers are studied by Broadband dielectric spectroscopy in the frequency range from 0.01Hz to 10MHz at temperatures between 120K and 500K. The alternating maleimide copolymers possess two different types of side chains: N-alkyl- or N-[4-N-(perfluoroheptylcarbonyl]aminobutyl]-substituted maleimide ring. Generally, four relaxation regions are observed for the polymer systems with alkyl side chains. The low temperature (high frequency) process is tentatively assigned to a local libration at the end of the alkyl chain, which can well be described by Arrhenius-type temperature dependence. A further process that is faster than the α-process is assigned to an out-of-plane motion of the succinimide ring. Finally, a dynamic glass transition process is observed very closely tied to a slower process that is assigned to fluctuations of the helical superstructure of the maleimide rings. In contrast, the perfluorinated polymer systems however show three relaxation regions only. The faster process at low temperatures is assigned to the librational motion of the fluorinated end groups while the other two processes are assigned to the α-process and modes of the helical superstructure.