Article,
Microwave preparation, structure and electrical properties of calcium-sodium-phosphate biosystem
JOURNAL OF NON-CRYSTALLINE SOLIDS, 352 (32-35): 3512-3517 (2006)7th Brazilian Symposium on Glasses and Related Materials/3rd International Symposium on Non-Crystalline Solids in Brazil, Maringa, BRAZIL, NOV 13-16, 2005.
DOI: 10.1016/j.jnoncrysol.2006.02.111
Abstract
The hydroxyapatite biomaterial (Ca-10(PO4)(6)(OH)(2) - HAP) is the main
mineral constituent of teeth and bones, with excellent biocompatibility
with hard and muscle tissues. These materials exhibit several problems
of handling and fabrication, which can be overcome by mixing them with a
suitable binder. In this study, a microwave process was used to produce
hydroxyapatite using the starting materials CaCl2 and Na2HPO4 with
previous precipitation. The mixture was exposed to microwave radiation
for 5, 10, 15 and 20 min through domestic microwave ovens with an output
power of I kW and frequency oscillation of 2.45 GHz. The samples were
analyzed by Xray powder diffraction, scanning electron microscopy,
energy dispersive X-ray, dc conductivity and impedance spectroscopy.
X-ray powder diffraction revealed the formation of HAP after 5 min of
exposure, The presence of a low crystallinity state and the transition,
with the rise of radiation exposure time, to a crystalline phase was
related to the Ca/P mass and Ca/P atomic ratio. The presence of this low
crystalline phase, detected by X-ray powder diffraction and scanning
electron microscopy, seems to have a direct influence on electrical and
dielectrical characteristics. (c) 2006 Elsevier B.V. All rights
reserved.
Tags
- ceramics;
- dielectric
- diffraction;
- electric
- electron
- glass
- microscopy;
- microwave;
- modulus;
- optical
- properties;
- properties}
- relaxation,
- scanning
- x-ray
- {biomaterials;
