LI Yuzhe 1, WU Mingchen 1, TAN Junjun 1, 2
(1. School of Materials and Chemical Engineering, Hubei University of Technology, Wuhan 430068, Hubei, China; 2. Hubei Provincial Key Laboratory of Green Light Industrial Materials, Hubei University of Technology,
Wuhan 430068, Hubei, China)
Abstract: Different hydroxyapatite (HA) nanoparticles were prepared by varying the sodium citrate to calcium ion molar ratio (CCR) using a sodium citrate-assisted hydrothermal method. The prepared HA nanoparticles were also composited with gelatin by using a solution blending method to obtain HA/gelatin composites. The related products and composites were characterized analytically by using X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), UV-vis spectroscopy and tensile measurement. Average length of the HA particles decreased from 100.8 nm to 41.8 nm, the average diameter decreased from 33.7 nm to 17.3 nm, and the surface charge of the HA particles in aqueous medium decreased from −3.7 mV to −33.0 mV, as the CCR increased from 0/6 to 4/6. Meanwhile, the elongation at break, tensile strength and Young's modulus changed from 1.56%, 45.3 MPa and 3.24 GPa to 6.00%, 77.7 MPa and 4.57 GPa, respectively, while transparency of the HA/gelatin composites increased from 5% to 55%. These results indicate that the increase in the CCR is not only beneficial to the reduction of HA particle size, but also to the enhancement of HA particle dispersion in aqueous medium. As a result, mechanical properties of the composites were effectively enhanced.
Key words: hydroxyapatite; gelatin; sodium citrate; namocomposites; transparency