Dresden 2009 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

CPP: Fachverband Chemische Physik und Polymerphysik

CPP 42: Polymer Physics IV

CPP 42.2: Vortrag

Freitag, 27. März 2009, 10:45–11:00, ZEU 160

Investigations of Chain Dynamics of Polymers Confined into Nanopores — •Salim Ok¹, Fabian Vaca Chavez², Martin Steinhart¹, and Kay Saalwächter² — ¹Max-Planck-Institut für Mikrostrukturphysik, Weinberg 2, 06120 Halle, Germany — ²Institute of Physics - Martin-Luther-University Halle-Wittenberg, Betty-Heimann-Str.7, 06120 Halle, Germany

Gaining better understanding of the nature of polymeric interphases in nanocomposites is still challenging. We show that self-ordered nanoporous anodic aluminum oxide (AAO) containing arrays of cylindrical channels with high aspect ratio and sharp diameter distribution is an ideal model system for the study of polymeric interphases in a well-defined anisotropic geometry. The chain dynamics of polybutadiene infiltrated into AAO was probed by Nuclear Magnetic Resonance (NMR) [1]. The mobility of polymer chains in nano-pores increased as a function of temperature systematically. However, comparing the bulk transverse relaxation (T₂) data with T₂ data in confined geometry shows that the mobility of the polymer molecules in the nano-pores is lower than the ones in the bulk. The less mobility is attributed to the smaller volume of the AAO nano-pores, restricting motion and entanglement of the polymer chains. The explanation is *corset effect*, defined as combined effect of impenetrable pore walls, the mutual uncrossability of polymer chains and the low compressibility of polymer chains [2].

[1] Saalwachter, K., Prog. NMR Spectroscopy, 51, 1 (2007) [2] Fatkullin, N. et al., New Journal of Physics, 6,1 (2004)