Intercalation of Hexylamine into Hydrated Kaolinite Phenylphosphonate.

Hydrated kaolinite phenylphosphonate (KPP-hyd) was reacted with hexylamine under ambient conditions. The reaction produced a stable light-yellow compound (KPP-hex) that was isolated and characterized by X-ray diffraction, thermal methods (simultaneous thermogravimetric and differential scanning calorimetric analysis), Fourier transform infrared spectroscopy, and elemental CHN analysis. The increase in the interlayer distance from 15.02 to 16.36 Å on going from KPP-hyd to KPP-hex was attributed to the replacement of water molecules with the longer hexylamine molecules in the phenylphosphonate P-O-H binding sites of the grafted KPP host. Upon heating, the phase KPP-hex release the hexylamine molecules that burn. The resulting KPP-dry is stable up to 498 degrees C, at which temperature the grafted phenylphosphonate begins to burn and the dehydroxilation of kaolinite takes place. Copyright 1999 Academic Press.