Dynamics, Fragility, and Glass Transition of Low-Molecular-Weight Linear Homopolymers

Laura Andreozzi (1) , Ciro Autiero (1) , Massimo Faetti (1) , Marco Giordano (1) , Fabio Zulli (2)

1 Physics
2 Physics

Analysis of the dynamics of low-molar-mass linear homopolymers is of importance to understand the mechanisms driving structural relaxation properties from molecular liquids to polymers. Theoretical models assume, in general, the same mobility of the different moieties of the macromolecule, but this hypothesis fails for low-molar-mass polymers. Therefore, isofrictional comparisons are necessary to interpret experimental data with theoretical models. In this work, the molar-mass dependence of the glass transition temperatures T_g, fragility indexes, and dynamic moduli of unentangled poly(ethyl acrylate) (PEA) melts are studied and discussed. All the results are interpreted in a coherent framework developed from the free-volume concept. The predictive power of this framework is also tested to fit theoretical and experimental master curves introducing an "inverse" isofrictional correction.

Mots clés: Physical Sciences

Laura Andreozzi, Ciro Autiero, Massimo Faetti, Marco Giordano, Fabio Zulli. Dynamics, Fragility, and Glass Transition of Low-Molecular-Weight Linear Homopolymers. Philosophical Magazine, 2008, 88 (33-35), pp.4151-4159. ⟨10.1080/14786430802468231⟩. ⟨hal-00513975⟩