Phosphonium salt intercalated montmorillonites

Abstract Tri-phenyl vinylbenzyl phosphonium chloride and tetraoctyl phosphonium bromide salts have been used as intercalant agents for Na-montmorillonite. Fourier Transform Infrared spectroscopy (FTIR) and Thermogravimetric Analysis coupled with Mass-spectrometry (TG/DTG-MS) were used to characterize the modified montmorillonites and the thermal decomposition products. X-ray Diffraction (XRD) and Transmission Electron Microscopy (TEM) techniques were used to evaluate the increase of the basal spacing. An easier and more effective intercalation takes place with the tetraoctyl phosphonium salt giving rise to a higher concentration of intercalant with a sensible increase in the interlayer spacing. This phosphonium salt modified montmorillonite is thermally more stable and easier to exfoliate during the compounding process.