Influence of a Reduced Mobility Layer on the Structural Relaxation Dynamics of Aluminum Capped Ultrathin Films of Poly(ethylene terephthalate)

• DOI: 10.1021/la062229j
• Publication Date: 2007-01-12T12:02:11Z
• Authors: Simone Napolitano; Daniele Prevosto; Mauro Lucchesi; Pasqualantonio Pi...; Mario D'Acunto; Pierangelo Rolla
• Keywords: POLYETHYLENE TEREPHTHALATE; GLASS-TRANSITION TEMPERATURE; RAY PHOTOELECTRON-SPECTROSCOPY; THIN POLYMER-FILMS; POLY(METHYL METHACRYLATE); 01 natural sciences; Sciences exactes et naturelles; 0104 chemical sciences

The structural dynamics of ultrathin polymer films poly(ethylene terephthalate) capped between aluminum electrodes have been investigated by dielectric relaxation spectroscopy. A deviation from bulk behavior, appearing as an increase the time at a fixed temperature, is observed for thickness below 35 nm. slowing down acts constant shift factor independent and fragility constant. interfacial energy calculated to be 3 mJ/m2, confirming strong interaction substrate, which leads presence layer characterized reduced mobility their interfaces. We proposed mathematical schematization multylayer model that allowed qualitative reproduction dependences static dynamic properties. In terms such model, upper limit was estimated 20 conditions extend different observables are finally suggested.