Rapid and quantitative displacement of poly(ethylene oxide) from MnPS3 and other layered hosts

The reaction of tetraethylammonium salt with the nanocomposites K-0.2(C2H4O)(2.3)M(0.9)PS(3) (M = Mn, Gel) under ambient conditions results in the rapid and quantitative displacement of the polymer and alkali metal to form the alkylammonium intercalate. Solid reactants and products, characterized using XRD, TGA, IR, gel permeation chromatography, and elemental analyses, show that these displacement reactions go to completion with no polymer degradation after initial formation of the nanocomposite. Pseudoreaction rates (0.0-7.8 min(-1)) are obtained using temporal XRD studies for different cations, concentrations, and polymer molecular weights. Reaction rates increase for lower polymer molecular weights, and a strong rate dependence is observed for alkylammonium concentration Displacement from the MPS(3) host occurs very slowly, or only to a limited extent, for tetramethylammonium, tetrapropylammonium, and tetrabutylammonium salts. A reaction mechanism is proposed from observed trends. Rapid displacement is also reported for other layered nanocomposites containing poly(ethylene oxide) within LixMoS2, Na-montmorillonite, and LixMoO3.