1979 B.S.
Chemistry, Aristotelion University of Thessaloniki, Greece
1982 M.A.
Chemical Physics, State University of New York, Binghamton,
New York, USA
1985 Ph.D.
Physical Chemistry, State University of New York, Binghamton, New
York, USA
1985-1986
Research Associate at Northeastern University, Boston, USA.
1988-1991
University of Crete, Chemistry Department.
1988 present Research
Scientist, FORTH, IESL Heraklion.
1991
Lecturer of Physical Chemistry, University of Crete.
1993 (Summer) Visiting Scientist, University
of Uppsala, Institute of Physical Chemistry, Uppsala, SWEDEN.
1995
Assistant Professor of Physical Chemistry, University of Crete.
1997-1998 Visiting
Professor at Binghamton University, New York, USA
RESEARCH AREA : Physical Chemistry -
Polymer Physics
RESEARCH INTERESTS:
Our research interests are in the physical chemistry and physics of polymeric
systems in order to characterize morphology, conformation and dynamics
both to polymers and copolymers in the melt state and in solution. In particular
our research concerns the dynamics of bulk polymers, polymer
blends, controlled release polymers and multicomponent
systems utilizing a variety of experimental techniques (Electron
Paramagnetic Resonance (both CW and pulsed),Dynamic Light Scattering
(Photon correlation spectroscopy and Fabry-Perot interferometry), Dielectric
Relaxation and Mechanical Spectroscopy). Our goals may
be identified as follows. First is through the combination of our
experimental tools to have a complete understanding of the fundamentals
of chain dynamics. Second is the clarification of the relationship
between macroscopic physical properties and the material microstructure.
The large dimensions of macromolecules lead to conformational rearrangements
which occur over many decades in time scale. Thus it is desirable for experiments
to cover as wide a dynamic range as possible. We make use of
the scattering of radiation from macromolecular systems to gain information
on diffusion mechanisms, conformational dynamics and time averaged conformations.
In quasi-elastic light scattering, very small frequency shifts in the scattered
beam are determined by photon correlation spectroscopy as a function
of scattering angle. These shifts may be related to dynamic processes involving
either the center-of-mass diffusion of the polymer or the rearrangements
of smaller portions of the molecule. The explosive growth of technology
combined with the rapid development of even new classes of materials
provides ongoing challenges to understand as-yet undiscovered materials
by starting at the atomic level and then gradually working up through the
ways that atoms pack together to larger dimensions.
SELECTED RECENT PUBLICATIONS:
"Dynamic Light Scattering Study of 3-indolbutyric Acid Polymeric
Derivative" A. K. Rizos, A. M. Tsatsakis, M. I. Shtilman, W.
Brown Polymer, 39, 1753 (1998).
"Cooperative Length Scale of Aroclor near its Dynamic Glass Transition"
A. K. Rizos and K. L. Ngai Materials Res. Soc.455, 141 (1997).
"Possible Causes of the Change of Dynamics in Glass-Forming Materials
Subjected to Reduced Dimension" K. L. Ngai and A. K. RizosMaterials Res. Soc.455, 147 (1997).
"Distribution of Reorientational Times of Optically Anisotropic
Molecular Liquids from Depolarized Light Scattering Studies" K. L.
Ngai, G. Floudas and A. K. RizosJ. Chem. Phys.106,
6957, (1997).
"Visccoelastic Properties of Amorphous Polymers V: a Coupling
Theory Analysis of the Thermorheological Complexity of Polyisobutylene
in the Glass-Rubber Transition Zone" K. L. Ngai, D. J. Plazek and A.
K. RizosJ. Polym. Sci. Polym. Phys. Ed., 35, 599
(1997).
"Local Segmental and sub-Rouse Modes in Polyisobutylene by Photon
Correlation Spectroscopy" A. K. Rizos, K. L. Ngai and D. J.
Plazek Polymer38, 6103 (1997).
"A New Depolarized Mode in a Binary Polymer Blend in the Critical Region"
A. K. RizosPolymer , 37, 5743 (1996).
"A Parameterless Explanation of the Non-Arrhenius Conductivity in Glassy
Fast Ionic Condactors" K. L. Ngai and A. K. RizosPhys. Rev. Lett., 76, 1296, (1996)
"Dynamic Heterogeneity and Complexity of Chemical Structure in Amorphous
Side Chain Polymers" G. Meier, F. Kremer, G. Fytas and A. K. RizosJ. Polym. Sci. Polym. Phys. Ed., 34, 1391 (1996).
"Component Dynamics in Polystyrene/Bis-2-ethylhexyl phthalate Solutions
by Polarized and Depolarized Light Scattering and Dielectric Spectroscopy"
A. K. Rizos, R. M. Johnsen, W. Brown and K. L. Ngai Macromolecules28, 5450 (1995).
"Concentration Fluctuation Effects on the Chain Orientation in Polymer
Blends in the Critical Region" A. K. Rizos, G. Fytas and A.
N. Semenov J. Chem. Phys.102, 6931 (1995).
"Determination of the coupling parameter of local segmental motion in
poly(isobutylene) by photon correlation spectroscopy" A. K. Rizos,
T. Jian and K. L. Ngai Macromolecules28, 517 (1995).
"Solvent Rotational Mobility in 1,2-Polybutadiene/Aroclor Solutions
by Dielectric Relaxation and Fabry-Perot Interferometry" A. K. Rizos
and K. L. Ngai Macromolecules27, 7076 (1994).
"Solvent Reorientation in Block Copolymer Solutions" A.
K. Rizos, K. L. Ngai, S. Pispas and N. Hadjichristidis J. of Non-Cryst.
Solids172-174, 790 (1994).
"Local Motions in Concentrated Solutions of Poly(Methyl methacrylate)/Bis(2-ethylhexyl
phthalate)" A. K. Rizos, G. Floudas and W. Brown J.
Non-Cryst. Solids172-174, 786 (1994).
"Local Molecular Motion in Polyurethane-Poly(methyl methacrylate)
Interpenetrating Polymer Networks" A. K. Rizos, G. Fytas, R.
J. Ma, C. H. Wang, V. Abetz and G. C. Meyer Macromolecules26, 1869 (1993).
"Segmental and Chain Dynamics in a Diblock Copolymer Melt near
the Microphase Separation Transition" G. Fytas, A. K. Rizos,
I. Alig, F. Kremer and J. Roovers Polymer34, 2263 (1993).
"Dynamic Light Scattering Study of a 1,4-Isoprene-b-Styrene Copolymer"
A. K. Rizos, G. Fytas, J. Roovers, K. L. Ngai Prog. Coll. and
Polym. Sci.91, 72 (1993).
"Solvent Reorientation Dynamics in Aroclor/Polymer Solutions"
A. K. Rizos, K. L. Ngai and G. Fytas Prog. Coll. and Polym. Sci.91, 135 (1993).
"Anomalous Reduction of Solvent Friction in Aroclor Solutions
of 1,2-Polybutadiene" A. K. Rizos and K. L. Ngai Phys.
Rev.B 46(13), 8126 (1992).
"Segmental Motion in Poly(styrene-b-1,4-isoprene) Block Copolymers
in the Disordered State" A. K. Rizos, G. Fytas and J. C. Roovers
J. Chem. Phys. 97, 6925 (1992).
INVITED SEMINARS:
Northeastern University, Physics Department, Boston, USA, April 1985.
University of Crete, Department of Chemistry, Heraklion, Crete, Greece,
March 1987.
Technische Hochscule Merseburg, Physics Department, Merseburg, Germany,
October 1989.
EPS Conference on Polymer Networks, Alexisbad, Germany, September
1991.
2nd Meeting of the Hellenic Polymer Association, Athens, Greece,
December 1991.
epf 92 European Polymer Federation Conference in Baden-Baden, Germany,
September 30, 1992.
University of Uppsala, Institute of Physical Chemistry, Sweden, October
1992.
SDLS II, Burg auf Fehmarn, March 1993, Germany.
National Technical University of Athens, Department of Physics, May
1993.
Workshop in Polymer Science, University of Patras, Department of
Chemical Engineering, November 1993.
207th National Meeting of the American Chemical Society, Symposium
on Block Copolymer Dynamics, San Diego, California, March 13-18, 1994.
209th National Meeting of the American Chemical Society, Anaheim,
California, April 2-6, 1995.
Materials Research Society 1996 Fall Meeting, Boston, MA, December 2 1996.
3rd International Discussion Meeting on Relaxations in Complex Systems,
Vigo, Spain, July 3, 1997.
Page created: Saturday, February 21, 1998
Revision Date: Friday, May 01, 1998
