Single-phase nanocomposites containing montmorillonite, MoS2, MoO3 or TiS2 with poly(ethylene oxide) are obtained by the exfoliation of the layered solid, adsorption of polymer, and subsequent precipitation of solid product. Aqueous solutions can be employed for these syntheses except PEO/TiS2, which is prepared from lithiated TiS, in an N-methyl formamide (NMF) solution. X-ray diffraction indicates that the resulting solids increase in basal-plane repeat by approximately 4 or 8 Angstrom, consistent with the incorporation of a single or double layer of polymer between inorganic layers, Reaction stoichiometries and elemental analyses provide compositions for the single-phase products.