Την Τετάρτη 23 Μαρτίου 2016 και ώρα 15:00 μ.μ. στην Αίθουσα Συνεδριάσεων 1ου ορόφου, της Κεντρικής Βιβλιοθήκης (ΒΥΠ) o Καθηγητής Milan Kumar Sanyal ερευνητής στο “Saha Institute of Nuclear Physics”, Kolkata, INDIA
θα παρουσιάσει διάλεξη με τίτλο:
''Unusual structural and electronic ordering in confined polymers''
ΠΕΡΙΛΗΨΗ ΔΙΑΛΕΞΗΣ
We shall discuss here the effect of nano-confinement in structural and electronic ordering in polymer films and wires respectively with three of our recent results as examples. The first example is the counter intuitive reversible crystallisation of two-dimensional monolayer of Trisilanolisobutyl Polyhedral Oligomeric SilSesquioxane (TBPOSS) on water surface. Amphiphilic TBPOSS form rugged monolayers and Grazing Incidence X-ray Scattering (GIXS) measurements reveal that the in-plane inter-particle correlation peaks, characteristic of two-dimensional system, observed before transition is replaced by intense localized spots after transition. In the second example we shall show that the hydrophobic monolayer of polystyrene form multi-molecular planar disk like aggregates on water surface and by the application of external stress the disks get tilted to form stair-case like buckled structures due to tectonic slip of the aggregates over each other. The third example illustrates electronic ordering in confined polymers. In-situ x-ray diffraction technique has been used to study the growth process of gold incorporated polypyrrole nano-wires that exhibit colossal dielectric constant due to existence of quasi-one-dimensional charge density wave state. This opens up a new possibility in the general areas of flexible nano-dielectric materials (FNDMs).
[1] R. Banerjee, M. K. Sanyal, M. K. Bera, A. Gibaud, B. Lin and M. Meron, Scientific Reports, 5 8497 (2015).
[2] M. K. Bera, M. K. Sanyal, R. Banerjee, P. M. Saville, J. W. White, B. Lin and M. Meron, (Submitted for Publication)
[3] A. Sarma and M. K. Sanyal, AIP ADVANCES 4, 097121 (2014); A. Rahman and M. K. Sanyal, ACS Nano. 7, 7894 (2013).