Title :
PTC Effect and Structure of Polymer Composites Based on Polypropylene/Co-Polyamide Blend Filled with Dispersed Iron
Author :
Kanapitsas, A. ; Tsonos, C. ; Logakis, E. ; Pandis, C. ; Pissis, P. ; Kontou, E. ; Mamunya, Y.P. ; Lebedev, E.V. ; Delides, C.G.
Author_Institution :
Technol. Educational Inst. of Lamia, Dept. of Electron., Athens
Abstract :
The temperature dependence of resistivity, structure and thermal expansion of composites based on polymer blend polypropylene/co-polyamide (PP/CPA) filled with dispersed iron (Fe) has been studied. The dependence of conductivity on filler content shows percolation behavior with the values of the percolation thresholds equal to 5 vol.% for the filled blend PP/CPA-Fe with two steps character of the conductivity curve. The evolution of structure of the composite PP/CPA-Fe demonstrates transition from polymer matrix CPA-Fe with inclusions of PP through co-continuous phases of both CPA-Fe and PP to PP matrix with inclusions of CPA-Fe. Such a structure occurs due to localisation of the filler only in one of the polymer phases, namely in CPA. The PP/CPA-Fe composites demonstrate PTC effect with the presence of a resistivity plateau. In such a system the PTC is caused by the break of the conductive structure of the filler inside the CPA-Fe phase due to the morphological changes in the vicinity of the melting temperature of CPA
Keywords :
filled polymers; iron; polymer blends; thermal conductivity; thermal expansion; thermal resistance; Fe; PTC effect; conductivity curve; dispersed iron; percolation thresholds; polymer blend; polymer composites; polymer matrix CPA-Fe; polypropylene/co-polyamide blend; temperature dependence; thermal expansion; Composite materials; Conductivity; Dispersion; Iron; Polymers; Powders; Temperature dependence; Temperature sensors; Thermal expansion; Viscosity;
Conference_Titel :
Microelectronics, 2006 25th International Conference on
Conference_Location :
Belgrade
Print_ISBN :
1-4244-0117-8
DOI :
10.1109/ICMEL.2006.1650975
