Dielectric relaxation phenomena and dynamics in polyoxymethylene/polyurethane/alumina hybrid nanocomposites

• Published in: Polymer international 2011-12, Vol.60 (12), p.1715-1721
• Main Authors: Psarras, Georgios C, Siengchin, Suchart, Karahaliou, Panagiota K, Georga, Stavroula N, Krontiras, Christoforos A, Karger-Kocsis, József
• Format: Article
• Language: English
• Subjects: Acetal resins; Aluminum oxide; Applied sciences; Boehmite; Composites; dielectric relaxation; Dynamics; Exact sciences and technology; Forms of application and semi-finished materials; hybrid nanocomposites; Latex; Nanocomposites; nanodielectrics; Polymer industry, paints, wood; Polyurethane resins; POM; Technology of polymers
• ISSN: 0959-8103; 1097-0126
• DOI: 10.1002/pi.3136

Ternary hybrid composites composed of polyoxymethylene (POM), polyurethane (PU) and boehmite alumina nanoparticles were produced by melt blending with and without latex pre‐compounding. PU latex pre‐compounding was employed for the fine dispersion of both the PU and alumina particles within the POM matrix. In this study the electrical properties of the POM/PU/boehmite alumina nanocomposites were examined by means of broadband dielectric spectroscopy over a wide temperature (−100 to 150 °C) and frequency (10−1 to 106 Hz) range. Data were analysed by means of the electric modulus formalism. The recorded relaxations include contributions from both polymers and the inorganic reinforcing phase. In the ternary hybrid systems five distinct relaxation processes were detected. Relaxations were assigned and interpreted by considering the morphology of the corresponding composite. In particular, they were attributed to the γ‐mode of POM and/or of PU, the α‐mode of PU, the α‐mode of POM and to the interfacial polarization process. Finally, the dynamics of all the recorded processes are examined and discussed. Copyright © 2011 Society of Chemical Industry Dielectric relaxations of ternary hybrid composites composed of polyoxymethylene, polyurethane and alumina nano‐particles were studied. Relaxations were assigned and interpreted by considering the morphology of the corresponding composites.