Conformation of Poly(ethylene oxide) Intercalated in Clay and MoS2 Studied by Two-Dimensional Double-Quantum NMR

The conformation of poly(ethylene oxide), PEO, intercalated in layered clays and MoS 2 has been characterized by double-quantum solid-state NMR. Using PEO with 13% 13 C− 13 C labeled units, the conformational statistics of the OC−CO bonds have been determined. The OC−CO bonds of the polymer in narrow interlayer gaps of ∼0.8, ∼0.85, and ∼1.0 nm thickness consistently exhibit a high gauche content of approximately 90%. This rules out models with highly trans-containing chains as found in certain complexes of PEO with HgCl 2 or p -nitrophenol.