Dresden 2011 – wissenschaftliches Programm

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CPP: Fachverband Chemische Physik und Polymerphysik

CPP 36: Poster: Nanoparticles and Composite Materials

CPP 36.5: Poster

Mittwoch, 16. März 2011, 17:00–19:00, P2

Structure Property Relationships of Nanocomposites based on Polyethylene and Layered Double Hydroxide — •Purv Purohit, Jesus Sanchez, and Andreas Schönhals — BAM Federal Institute for Materials Research and Testing, Unter den Eichen 87, 12205 Berlin, Germany

Nanocomposites based on Polyethylene (PE) and modified ZnAl Layered Double Hydroxides (ZnAl-LDH) were prepared and investigated by a combination of differential scanning calorimetry (DSC), Small and Wide angle X-ray scattering (SAXS & WAXS) and Dielectric Relaxation Spectroscopy. Space resolved SAXS investigation show that the samples are homogeneous on a length scale of several cm and have a predominantly intercalated morphology. DSC and WAXS show that the degree of crystallinity decreases with the increasing content of LDH. The extrapolation of this dependence to zero estimates a limiting concentration of c.a. 40% LDH where the crystallization of PE is completely suppressed. The dielectric response of the nanocomposites shows several relaxation processes. The intensity of the dynamic glass transition increases with the concentration of LDH. This is attributed to the increasing concentration of the exchanged anion dodecylbenzene sulfonate (SDBS), which are adsorbed at the LDH layers. Therefore, analysis of the beta-relaxation provides information about the interfacial region between the LDH layers and the PE matrix. The glass transition temperature in this interfacial region is somewhat lower than for pure PE. This is accompanied by a change of the fragility deduced from the relaxation map.