Polymer dynamics in solid-state matrices studied by field-cycling NMR

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The aim of the proposal is to characterise the local glassy dynamics as well as the collective dynamics of polymers embedded in solid-state matrices (nanoconfinement of different sizes) by means of different nuclear magnetic resonance (NMR) methods. Special focus is given on applying electronic (fast) field-cycling (FFC) 1H NMR which is particularly suited for probing the slow polymer dynamics. Selected solid-state 1H and 2H NMR will complement the studies. FFC NMR investigations have shown for certain polymers that the collective dynamics are significantly changed with respect to their bulk behaviour when they are embedded in a confinement ranging from 60 nm – 1000 nm, a length scale much larger than the size of a polymer in the melt. So far this so called corset effect is not well understood – and a disputed phenomenon, as other experiments have challenged these results. Thus, the proposal is devoted to experimentally validating and promoting the understanding of the corset effect. We study the interplay of glassy and polymer dynamics in different porous systems with pores sizes in the range of 5 nm up to 1000 nm.