Local Structure of Polyethylene Glycol–Nal Solid Polyelectrolyte as Studied by 13C and 23Na NMR

Abstract

Abstract 13C CP/MAS NMR, 23Na powder NMR, and 23Na two dimensional nutation NMR were applied to complexes of Nal with polyethylene glycol (PEG) and tetraethylene glycol (TEG) to study the conformation of the polyethers and local structure around the Na+. 13C chemical shift data suggest strongly that the polyether chains assume the gauche conformation in the complexes. 23Na NMR spectrum of TEG–Nal complex gave a broad asymmetric line; simulation of the line shape led to e2Qq⁄h=590 kHz and η=0.7. No significant temperature dependence of the line shape was observed between 200 K and room temperature. For PEG–Nal complex e2Qq⁄h and η were estimated to be about 320 kHz and 0.7, respectively, from the nutation spectrum. On the basis of the above results, new model structures of PEG–Nal complex were presented.