I graduated from the University of Patras (Greece), in 2003, with a Diploma in physics. I then obtained my M.Sc. degree in materials science and technology, in 2005, and my Ph.D. degree in polymer physics, in 2009, both at the National Technical University of Athens (Greece). From 2010 to 2011 I worked as a Research Fellow in Cranfield University (UK), leading the development and implementation of hybrid nano-composite materials in aerospace applications in the frame of an EU FP7 project. Since 2011, I am working in the Materials group of the ABB Research Center in Switzerland. I have authored 33 peer-reviewed publications (h-index of 17, about 1400 citations) and I am inventor in 10 patents and patent applications.
2013 IEEE International Conference on Solid Dielectrics (ICSD), 2013
ABSTRACT A general model is introduced for electric conduction in polymer insulation used in high... more ABSTRACT A general model is introduced for electric conduction in polymer insulation used in high voltage direct current (HVDC) applications. It is shown that for the often occurring case where majority carrier injection is relevant, a generic boundary condition model is unavoidable. Furthermore, the smallness of the conduction current requires to take dynamic polarization into account in a general DC conduction model. Both issues are illustrated with simulation results and experimental observations.
2006 25th International Conference on Microelectronics, 2006
ABSTRACT The temperature and frequency dependence of dielectric permittivity of hybrid polyimide/... more ABSTRACT The temperature and frequency dependence of dielectric permittivity of hybrid polyimide/silica nanocomposites, prepared by the in situ generation of crosslinked organosilicon nanophase by sol-gel techniques, was investigated by broadband dielectric relaxation spectroscopy. Dielectric permittivity decreases and its frequency and temperature dependence becomes weaker in the hybrids as compared to pure polyimide. The results are explained in terms of loose inner structure of the spatial aggregates of the organosilicon nanophase and reduced polymer dynamics in the hybrids. Water sorption measurements from the vapor phase show reduced water contents of the nanocomposites with respect to pure polyimide. These results suggest that the hybrids under investigation may have a reasonably good potential as low-k materials for microelectronics applications
ABSTRACT The surface charge behavior on epoxy plates pre-charged by corona in SF6 is investigated... more ABSTRACT The surface charge behavior on epoxy plates pre-charged by corona in SF6 is investigated by surface potential decay measurements. The temperature dependence of the charge mobility estimated from surface potential decay is compared to the DC volume conductivity obtained from conventional current-voltage measurements. Furthermore, the effect of the temperature and the initial field on the charge decay mechanisms is studied. This is of particular practical importance for applications because considerable temperature gradients along the epoxy insulators in gas-insulated switchgears (GIS) separating the hot conductor from the cold ground can appear. Different surface charge controlling mechanisms may predominate at different locations on a GIS insulator.
... Additional Information. How to Cite. Mičuík, M., Omastová, M., Pionteck, J., Pandis, C., Log... more ... Additional Information. How to Cite. Mičuík, M., Omastová, M., Pionteck, J., Pandis, C., Logakis, E. and Pissis, P. (2011), Influence of surface treatment of multiwall carbon nanotubes on the properties of polypropylene/carbon nanotubes nanocomposites. ...
Journal of Polymer Science Part B: Polymer Physics, 2009
... G. Bontchev str. bl. 103A, Sofia 1113, Bulgaria. Email: C. Pandis (pandis@mail.ntua. gr). *Co... more ... G. Bontchev str. bl. 103A, Sofia 1113, Bulgaria. Email: C. Pandis (pandis@mail.ntua. gr). *Correspondence: C. Pandis, National Technical University of Athens, Zografou Campus 15780, Athens, Greece. Publication History. Issue ...
ABSTRACT Polyimide nanocomposites prepared by the in situ generation of crosslinked organosilicon... more ABSTRACT Polyimide nanocomposites prepared by the in situ generation of crosslinked organosilicon nanophase by sol-gel techniques were investigated by dielectric relaxation spectroscopy, themally stimulated depolarization currents and dynamic mechanical analysis. Two series of samples were investigated with molar mass 5000 and 10000 of the polyimide chains. In both series a non-additive decrease of the dielectric permittivity with increasing amount of filler was observed, indicating a loose inner structure of the spatial aggregates of the organosilicon nanophase. The magnitude of the dielectric γ relaxation of polyimide was found to increase with increasing filler content for the shorter chains, whereas the opposite was observed for the longer ones.
In this work, syndiotactic polypropylene/multiwalled carbon nanotubes (MWCNT) nanocomposites, in ... more In this work, syndiotactic polypropylene/multiwalled carbon nanotubes (MWCNT) nanocomposites, in various concentrations, were produced using melt mixing. The influence of the addition of MWCNT on the morphology, crystalline form, and the thermal and electrical properties of the polymer matrix was studied. To that aim, scanning electron microscopy, Raman spectroscopy, X-ray diffraction, differential scanning calorimetry, and dielectric relaxation spectroscopy were employed.
Poly (ethylene terephthalate)(PET)/multi-walled carbon nanotube (MWCNT) nanocomposites were prepa... more Poly (ethylene terephthalate)(PET)/multi-walled carbon nanotube (MWCNT) nanocomposites were prepared by three different methods: in-situ polymerization technique (IS), direct mixing in the melt (DM) and dilution of a 0.5 wt.% masterbatch, synthesized via ...
European Journal of Pharmaceutics and Biopharmaceutics, 2001
Biomedical collagen preparations are mainly based on liquid aqueous preparations either used dire... more Biomedical collagen preparations are mainly based on liquid aqueous preparations either used directly as injectables or transferred for example into solid implants or porous devices. In all cases the viscosity of the dispersion or solution has to be controlled or adjusted by pH, temperature, collagen concentration or crosslinking. We tested these effects on the rheological and structural properties of collagen fiber dispersions focusing on oscillatory rheometry. With increasing difference between pH and pI viscosity increased and went through a maximum with less rigidity of the fibers. The dispersions acted like a predominantly permanently linked network. This character changed to only partially linked at low collagen concentration due to isolation of the individual fibers. Up to 40 degrees C, temperature is a tool suitable for adjusting viscosity without changes in the network structure. At 50 degrees C, fourier transform - infrared spectroscopy (FT-IR) spectroscopy indicated the transition of the helical into random coil structure. Renaturation of the helices was found upon cooling but atomic force microscopy (AFM) indicated severe temperature induced damages of the fibers. Crosslinking with glutaraldehyde (GTA) leads to an increase in viscosity and the effect on the network structure depends on the processing conditions.
2013 IEEE International Conference on Solid Dielectrics (ICSD), 2013
ABSTRACT A general model is introduced for electric conduction in polymer insulation used in high... more ABSTRACT A general model is introduced for electric conduction in polymer insulation used in high voltage direct current (HVDC) applications. It is shown that for the often occurring case where majority carrier injection is relevant, a generic boundary condition model is unavoidable. Furthermore, the smallness of the conduction current requires to take dynamic polarization into account in a general DC conduction model. Both issues are illustrated with simulation results and experimental observations.
2006 25th International Conference on Microelectronics, 2006
ABSTRACT The temperature and frequency dependence of dielectric permittivity of hybrid polyimide/... more ABSTRACT The temperature and frequency dependence of dielectric permittivity of hybrid polyimide/silica nanocomposites, prepared by the in situ generation of crosslinked organosilicon nanophase by sol-gel techniques, was investigated by broadband dielectric relaxation spectroscopy. Dielectric permittivity decreases and its frequency and temperature dependence becomes weaker in the hybrids as compared to pure polyimide. The results are explained in terms of loose inner structure of the spatial aggregates of the organosilicon nanophase and reduced polymer dynamics in the hybrids. Water sorption measurements from the vapor phase show reduced water contents of the nanocomposites with respect to pure polyimide. These results suggest that the hybrids under investigation may have a reasonably good potential as low-k materials for microelectronics applications
ABSTRACT The surface charge behavior on epoxy plates pre-charged by corona in SF6 is investigated... more ABSTRACT The surface charge behavior on epoxy plates pre-charged by corona in SF6 is investigated by surface potential decay measurements. The temperature dependence of the charge mobility estimated from surface potential decay is compared to the DC volume conductivity obtained from conventional current-voltage measurements. Furthermore, the effect of the temperature and the initial field on the charge decay mechanisms is studied. This is of particular practical importance for applications because considerable temperature gradients along the epoxy insulators in gas-insulated switchgears (GIS) separating the hot conductor from the cold ground can appear. Different surface charge controlling mechanisms may predominate at different locations on a GIS insulator.
... Additional Information. How to Cite. Mičuík, M., Omastová, M., Pionteck, J., Pandis, C., Log... more ... Additional Information. How to Cite. Mičuík, M., Omastová, M., Pionteck, J., Pandis, C., Logakis, E. and Pissis, P. (2011), Influence of surface treatment of multiwall carbon nanotubes on the properties of polypropylene/carbon nanotubes nanocomposites. ...
Journal of Polymer Science Part B: Polymer Physics, 2009
... G. Bontchev str. bl. 103A, Sofia 1113, Bulgaria. Email: C. Pandis (pandis@mail.ntua. gr). *Co... more ... G. Bontchev str. bl. 103A, Sofia 1113, Bulgaria. Email: C. Pandis (pandis@mail.ntua. gr). *Correspondence: C. Pandis, National Technical University of Athens, Zografou Campus 15780, Athens, Greece. Publication History. Issue ...
ABSTRACT Polyimide nanocomposites prepared by the in situ generation of crosslinked organosilicon... more ABSTRACT Polyimide nanocomposites prepared by the in situ generation of crosslinked organosilicon nanophase by sol-gel techniques were investigated by dielectric relaxation spectroscopy, themally stimulated depolarization currents and dynamic mechanical analysis. Two series of samples were investigated with molar mass 5000 and 10000 of the polyimide chains. In both series a non-additive decrease of the dielectric permittivity with increasing amount of filler was observed, indicating a loose inner structure of the spatial aggregates of the organosilicon nanophase. The magnitude of the dielectric γ relaxation of polyimide was found to increase with increasing filler content for the shorter chains, whereas the opposite was observed for the longer ones.
In this work, syndiotactic polypropylene/multiwalled carbon nanotubes (MWCNT) nanocomposites, in ... more In this work, syndiotactic polypropylene/multiwalled carbon nanotubes (MWCNT) nanocomposites, in various concentrations, were produced using melt mixing. The influence of the addition of MWCNT on the morphology, crystalline form, and the thermal and electrical properties of the polymer matrix was studied. To that aim, scanning electron microscopy, Raman spectroscopy, X-ray diffraction, differential scanning calorimetry, and dielectric relaxation spectroscopy were employed.
Poly (ethylene terephthalate)(PET)/multi-walled carbon nanotube (MWCNT) nanocomposites were prepa... more Poly (ethylene terephthalate)(PET)/multi-walled carbon nanotube (MWCNT) nanocomposites were prepared by three different methods: in-situ polymerization technique (IS), direct mixing in the melt (DM) and dilution of a 0.5 wt.% masterbatch, synthesized via ...
European Journal of Pharmaceutics and Biopharmaceutics, 2001
Biomedical collagen preparations are mainly based on liquid aqueous preparations either used dire... more Biomedical collagen preparations are mainly based on liquid aqueous preparations either used directly as injectables or transferred for example into solid implants or porous devices. In all cases the viscosity of the dispersion or solution has to be controlled or adjusted by pH, temperature, collagen concentration or crosslinking. We tested these effects on the rheological and structural properties of collagen fiber dispersions focusing on oscillatory rheometry. With increasing difference between pH and pI viscosity increased and went through a maximum with less rigidity of the fibers. The dispersions acted like a predominantly permanently linked network. This character changed to only partially linked at low collagen concentration due to isolation of the individual fibers. Up to 40 degrees C, temperature is a tool suitable for adjusting viscosity without changes in the network structure. At 50 degrees C, fourier transform - infrared spectroscopy (FT-IR) spectroscopy indicated the transition of the helical into random coil structure. Renaturation of the helices was found upon cooling but atomic force microscopy (AFM) indicated severe temperature induced damages of the fibers. Crosslinking with glutaraldehyde (GTA) leads to an increase in viscosity and the effect on the network structure depends on the processing conditions.
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