Zirconium phosphate organically intercalated/exfoliated with long chain amine

Nanolayered zirconium phosphate was synthesized by the direct precipitation reaction method, and it was organically modified with long chain amine (octadecylamine) at different amine:phosphate ratios (0.5:1, 1:1, and 2:1). Both zirconium phosphate and amine were dispersed in a 2:1 ethanol/water solution. Infrared spectroscopy (FT-IR), thermogravimetry (TG/DTG), differential scanning calorimetry, wide-angle X-ray diffraction (WAXD), and scanning electron microscopy (SEM) were used for characterization. The amine:phosphate ratio regulated the amine insertion in the zirconium phosphate lamellae, as observed by infrared bands, thermal curves, and SEM images. Different TG/DTG degradation temperatures evidenced adsorbed and bonded amine molecules in the phosphate lamellae. Calorimetric results indicated several amine melting temperatures suggesting different crystal arrangements in the phosphate galleries. The presence of octadecylamine changed the crystallographic features of the zirconium phosphate as observed in WAXD.