Effect of polyethylene glycol on the synthesis of hydroxyapatite obtained via microwave-assisted hydrothermal method

This study investigates the impact of varying concentrations of polyethylene glycol (PEG) (0, 0.1, 0.2, 0.3%wt) on the morphology of hydroxyapatite (HAp) synthesized via a microwave-assisted hydrothermal method, using Ca(NO₃)₂⋅4H₂O and (NH₄)₂HPO₄ as precursors. Scanning electron microscopy revealed the formation of nanowhiskers with widths of 20–30 nm and lengths of 60–80 nm, with Ca/P ratios ranging from 0.75 to 1.29, depending on the PEG concentration. X-ray diffraction identified both hexagonal and monoclinic phases, with crystallite sizes varying from 18.28 to 53.34 nm. Fourier transform infrared spectroscopy confirmed the presence of characteristic PO₄³⁻ and OH⁻ groups, as well as C–H bond bands from PEG. The findings suggest that PEG effectively controls the morphology and particle size of HAp.