Segmental relaxations have macroscopic consequences in glassy polymer films

• Verfasst von: Chowdhury, Mithun [VerfasserIn]
• Verfasst von: Freyberg, Paul [VerfasserIn]
• Verfasst von: Ziebert, Falko [VerfasserIn]
• Verfasst von: Yang, Arnold C.-M. [VerfasserIn]
• Verfasst von: Steiner, Ullrich [VerfasserIn]
• Verfasst von: Reiter, Günter [VerfasserIn]
• Titel: Segmental relaxations have macroscopic consequences in glassy polymer films
• Verf.angabe: Mithun Chowdhury, Paul Freyberg, Falko Ziebert, Arnold C.-M. Yang, Ullrich Steiner, and Günter Reiter
• E-Jahr: 2012
• Jahr: 27 September 2012
• Umfang: 5 S.
• Fussnoten: Gesehen am 27.09.2022
• Titel Quelle: Enthalten in: Physical review letters
• Ort Quelle: College Park, Md. : APS, 1958
• Jahr Quelle: 2012
• Band/Heft Quelle: 109(2012), 13, Artikel-ID 136102, Seite 1-5
• ISSN Quelle: 1079-7114
• DOI: doi:10.1103/PhysRevLett.109.136102
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 180783803X

Abstract

We have investigated the consequences of physical aging in thin spin-coated glassy polystyrene films through detailed dewetting studies. A simultaneous and equally fast exponential decay of dewetting velocity, width, and height of the rim with aging time was observed, which is related to a reduction of residual stresses within such films. The temperature dependence of these decay times followed an Arrhenius behavior, yielding an activation energy of 70±6 kJ/mol, on the same order of magnitude as values for the β-relaxation of polystyrene and for relaxations of surface topographical features. Our results suggest that rearrangements at the level of chain segments are sufficient to partially relax frozen-in out-of-equilibrium local chain conformations, i.e., the cause of residual stresses, and they might also be responsible for macroscopic relaxations at polymer surfaces.