Solid-State NMR Studies On The Interaction Between The Host And Guest Molecules In Quaternary Ammonium Intercalated α-Zirconium Phosphate

The research in the process of intercalation in layeredα-zirconium phosphate (α-ZrP) had important significance on the widely fields such as preparing new nanocomposites. Quaternary ammonium salt intercalatedα-ZrP had unique properties as former body. Based on solid-state NMR technology as the main method and XRD, IR and TG, we researched the intercalated/exfoliatedα-ZrP with the quaternary ammonium salt.We used the several methods of distinguish the interlayer and outersurface adsorbed guest by solid-state NMR technology. In solid state 13C NMR spectrum of compounds, there were two peaks of methyl. The peak atδ55.2 represented strong interaction, the motion was constrained cross polarization efficiency between 1H and 13C was higher, cross polarization efficiency TCH was shorter and the peak atδ55.9 represented weak interaction, cross polarization efficiency between 1H and 13C was lower, cross polarization efficiency TCH was longer. In the determination longitudinal relaxation time T1 of 13C, the T1 of the methyl atδ55.9 was longer, the mobility of the guest was stronger; The T1 of the methyl atδ55.2 was shorter; the mobility of the guest was weaker.By analysis of the solid state NMR spectroscopy of different samples under different conditions, we allocated the peaks. In 31P MAS NMR spectroscopy, in addition to the chemical shift ofα-ZrP atδ-18.7, there was a peak atδ-21.8 which corresponding toδ55.2 in 13C CP/MAS NMR spectroscopy. There were two molecules of water in the state ofδ-21.8. After high-temperature processing, the samples were dehydrated. The chemical shift in 13C NMR spectroscopy of methyl of the guest TMA changed toδ57.0. Meanwhile in 31P MAS NMR spectra, it appeared a new chemical shift atδ-13.4 with the absent ofδ-21.8. The state was P-O-N(CH3)4+. It was obtained by dehydrating two molecules of water from the state ofδ-21.8. The other peaks in the 31P NMR spectra contacted with different number of water molecules and forms of hydrogen bonds. We obtained the interaction models between theα-ZrP and TMA.