title: Polymer chain dynamics: evidence of nonexponential mode relaxation using thermally stimulated depolarization current techniques.
abstract: The slowest (p=1) mode relaxation of several polyisoprenes has been experimentally isolated by thermally stimulated depolarization current techniques. Close to the glass transition the p=1 mode deviates from the exponential behavior assumed by Rouse and tube-reptation theories. This effect is found to be a consequence of the closeness of τ_{p=1} and α-relaxation time scales. The scenario resembles that of broadened fast component dynamics in polymer blends with high dynamic asymmetry and suggests a possible general interpretation in terms of the effect of local density fluctuations (α relaxation) on chain dynamics.
authors.affiliation: Centro Física de Materiales (MPC), Centro Mixto CSIC-UPV/EHU, Paseo Manuel Lardizabal 5, 20018 San Sebastián, Spain.
authors.forename: S
authors.initials: S
authors.lastname: Arrese-Igor
authors.affiliation: Centro Física de Materiales (MPC), Centro Mixto CSIC-UPV/EHU, Paseo Manuel Lardizabal 5, 20018 San Sebastián, Spain and Departamento de Física de Materiales UPV/EHU, Apartado 1072, 20080 San Sebastián, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Alegría
authors.affiliation: Centro Física de Materiales (MPC), Centro Mixto CSIC-UPV/EHU, Paseo Manuel Lardizabal 5, 20018 San Sebastián, Spain and Departamento de Física de Materiales UPV/EHU, Apartado 1072, 20080 San Sebastián, Spain and Donostia International Physics Center, Paseo Manuel Lardizabal 4, 20018 San Sebastián, Spain.
authors.forename: J
authors.initials: J
authors.lastname: Colmenero