Abstract
Nano-sized crystals of calcined hydroxyapatite (HAp) having spherical morphologies were fabricated by calcination at 800°for 1 h with an anti-sintering agent surrounding the original HAp particles and the agent was subsequently removed by washing after calcination. The original HAp particles were prepared by a modified emulsion system, and surrounded with poly(acrylic acid, calcium salt) (PAA-Ca) by utilizing a precipitation reaction between calcium hydroxide and poly(acrylic acid) adsorbed on the HAp particle surfaces in an aqueous medium. In the case of calcination without PAA-Ca, micron-sized particles consisting of sintered polycrystals were mainly observed by scanning electron microscopy, indicating the calcination-induced sintering among the crystals. On the other hand, most of the crystals calcined with the anti-sintering agent were observed as isolated particles, and the mean size of the HAp crystals was around 80 nm. This result indicates that PAA-Ca and its thermally decomposed product, CaO, surrounding the HAp crystals could protect them against calcination-induced sintering during calcination at 800°The HAp crystals calcined with PAA-Ca showed high crystallinity, and no other calcium phosphate phases could be detected.
| Original language | English |
|---|---|
| Pages (from-to) | 848-851 |
| Number of pages | 4 |
| Journal | Journal of Nanoscience and Nanotechnology |
| Volume | 7 |
| Issue number | 3 |
| DOIs | |
| Publication status | Published - Mar 1 2007 |
| Externally published | Yes |
Keywords
- Calcination
- Ceramics
- Dispersibility
- Hydroxyapatite
- Nano
ASJC Scopus subject areas
- Bioengineering
- Chemistry(all)
- Biomedical Engineering
- Materials Science(all)
- Condensed Matter Physics