Influence of chain-end relaxation on the primary and secondary relaxation of supercooled polymeric liquids
Polymères, Colloids et Interfaces,
UMR-CNRS, Université du Maine 72085 le Mans Cedex 9, France
Accepted: 22 December 2000
We have studied the effect of chain-end relaxation on the α- and the β-relaxation of polymer melts by introducing hydrogen bonding end-groups while keeping the chain backbone the same. Hydrogen bonding of the chain ends increases the glass transition temperature (), but the shape of the α-relaxation and its temperature dependence as a function of are not influenced. The β-relaxation is much broader in the presence of hydrogen bonds between chain ends, but its temperature is correlated with . The results seem to imply that the β-relaxation process is not necessarily a specific localized motion of a group of atoms as is often assumed.
PACS: 64.70.Pf – Glass transitions / 61.25.Hq – Macromolecular and polymer solutions; polymer melts; swelling / 82.30.Nr – Association, addition, insertion, cluster formation, hydrogen bonding
© EDP Sciences, 2001