Polymer and Colloid Science Group

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Polymer and Colloid ScienceGroup

• People
• Research Activities
• Collaborations
• Output
• Funding
• Selected Presentations

IESL03/ 2006
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PEOPLE (current state)

• B. Loppinet, G. Petekidis (Researchers)
• G. Fytas, D. Vlassopoulos (Dept. Mat. Sci.
  Faculty Members)
• A. Larsen Physics Technician

• Post Docs E. van Ruymbeke,
• PhD Students M. Gianneli, M. Kapnistos, V.
  Michailidou,
• M. Stiakakis, Cheng Wei,

• MS-StudentsN. Gomopoulos, N. Koumakis,
• P. Voudouris
• Five diploma work Students

• Visiting Scientists T. Caremans (Leuven), E.
  Filippidi (Harvard),
• J. Gapinski (Poznan), A. Kröger (Mainz),
• K. Pham (Edinburgh), S. Roberts (N. Zealand),
• E. Sanders (Eindhoven), T.Sanders (Eindhoven),
  
• J. Stellbrink (Jülich)

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Research Activities

• Problems
• Soft Colloids effective interactions, dynamics
  and rheology
• Dynamics and non-linear rheology of colloidal
  glasses and gels
• Dynamics of surface tethered polymers
• Macromolecular architecture, self assembly and
  relaxation in polymeric systems
• Laser induced concentration gradients in
  transparent polymer solutions
• Phonons in soft structures

• Development of Experimental Tools
• EWDLS and combination with SPR
• Combination of DLS-Echo and Rheology
• FCS in Polymer Science
• BS of soft structures

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Collaborations
Over the Globe

• Examples of

international
national collaborations
P. N. Pusey, Edinburgh (Faraday Disc. 2004) C. Likos, Düsseldorf (PRL 2003) J. Rühe, IMTEK Freiburg (PRL 2004) E. L. Thomas, MIT (PRL 2005) MPIP (Mainz) E. N. Economou, IESL (PRL 2003) N. Vainos, EIE (Science 2002, JACS 2005) N. Hadjichristidis (Macromolecules) ICEHT Patras S. Yannopoulos, B. Marranzas Demokritos T. Vourlinos D. N. Theodorou
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Selected Presentations

• 1. Polymers
• Responsive Brushes
• Control Processing
• (through macromolecular architecture)

• 2. Colloids
• Vitrification and flow of colloidal glasses and
  gels
• Hypersonic phononic crystals

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Light scattering in the evanescent geometry
Polymer Brush Dynamics
G. F., Science 1996
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Responsive Brushes
PS brushes in marginal solvent (cyclohexane)
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Rheology of Branched Polymers

• Seniority Rules Outer branches relax first.
  Separated in time relaxation processes.
• Mean Field tube model.

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Vitrification and flow of colloidal glasses and
gels
Effects of Interparticle Interactions From Hard
Spheres to Repulsive (soft) and Attractive Systems
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Light Scattering Echo RheologyDynamic Light
scattering under oscillatory shear
G. Petekidis et al. Faraday Discuss. (2003)
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self-assembling and infiltration procedures
J.Wang,U.Jonas
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Inelastic Brillouin Light Scattering
H.Kriegs(2003)
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Bragg gap
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Scattering Geometry
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Music of Spheres
1.Dry Opals particle vibrations (elastic
constants)
W. Cheng J.C.P (2005), M.Faatz Langmuir(2005)
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Perspectives (research character)
Molecular Objects
Desired Function
Advanced Fields
Design
Phononic Devices, Sensors, Motors
Antagonistic Forces, Selection
Appropriate Morphology, Recognition
eg. Polymers Colloids
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Future directions/needs

• Bio-functional surface architecture
• (external collaboration J. Rühe, J. Knoll)
• Understanding of self-assembly and functions of
  bio-related systems
• (collaborations K. Tokatlidis, A. Mitraki,
  University of Crete)
• Single Macromolecule probing and manipulation

• Needs
• Soft Matter theory/simulation
• Experimentalist in biorelated systems