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CPP: Fachverband Chemische Physik und Polymerphysik
CPP 50: Poster Session III
CPP 50.40: Poster
Dienstag, 17. März 2020, 14:00–16:00, P1C
Low-resolution NMR investigations of polymer immobilization in nanocomposites — •Mozhdeh Abbasi1, Sol Mi Oh2, Alexander Eckert3, So Youn Kim2, Andreas Walther3, and Kay Saalwächter1 — 1Inst. f. Physik - NMR, Martin-Luther-Univ. Halle-Wittenberg, Halle (Saale), Germany — 2School of Energy and Chemical Engineering, UNIST, Ulsan, Republic of Korea — 3Inst.f. Makromolekulare Chemie, Albert-Ludwigs-Univ. Freiburg, Germany
We used low-resolution 1H NMR spectroscopy to study the molecular dynamics of poly (ethylene oxide), mixed with spherical silica nanoparticles [1] as well as self-assembled clay sheets (NHT) forming nacre-mimetics [2] as model materials. The decomposition of time-domain signals (FIDs) reveals three different phases of PEO with different dynamics, based on different transverse relaxation behavior [3] which are related to the strength of the dipolar coupling between proton spin pairs. Therefore, fast initial decay on the time scale of microseconds corresponds to a rigid phase with strong dipolar couplings, attributed to the intercalated part of PEO within the clay sheets or adsorbed chains on the silica surface. The intermediate phase with residual dipolar couplings and a mobile phase with faster segmental motions and a rather long T2 corresponds to free polymer chains. This study addresses the different molecular dynamics of PEO chains subject to different constraints in the two different nanocomposite structures. [1] S. Y. Kim et. al., Macromolecules 2012, 45, 4225. [2] P. Das et al., Nat. Commun. 2015, 6, 1. [3] K. Schäler et. al., Macromolecules 2013, 46, 7818.