Calcination of rod-like hydroxyapatite nanocrystals with an anti-sintering agent surrounding the crystals

Masahiro Okada, T. Furuzono

Research output: Contribution to journalArticle

31 Citations (Scopus)

Abstract

Sintering-free nanocrystals of calcined hydroxyapatite (HAp) having a rod-like morphology were fabricated by calcination at 800°C for 1 h with an anti-sintering agent surrounding original HAp particles and the agent was subsequently removed after calcination. The original HAp particles having a rod-like morphology with a size ranging from 30 to 80 nm (short axis) and 300 to 500 nm (long axis) were prepared by wet chemical process, and poly(acrylic acid, calcium salt) (PAA-Ca) was used as the anti-sintering agent. In the case of calcination without additives, the mean size of HAp crystals dispersed in an ethanol medium increased by about 4 times and the specific surface area of the crystals exhibited a 25% decrease compared to those of the original HAp particles because of calcination-induced sintering among the crystals. On the other hand, the HAp crystals calcined with the anti-sintering agent, PAA-Ca, could be dispersed in an ethanol medium at the same size as the original particles, and they preserved the specific surface area after calcination. These results indicate that PAA-Ca and/or its thermally decomposed product, CaO, surrounded the HAp particles and protected them against calcination-induced sintering during calcination. The HAp crystals calcined with PAA-Ca showed high crystallinity, and no other calcium phosphate phases could be detected after washing with water.

Original languageEnglish
Pages (from-to)807-815
Number of pages9
JournalJournal of Nanoparticle Research
Volume9
Issue number5
DOIs
Publication statusPublished - Oct 2007
Externally publishedYes

Fingerprint

Hydroxyapatite
Nanocrystals
Sintering
Durapatite
Calcination
roasting
sintering
nanocrystals
Crystal
rods
Crystals
crystals
carbopol 940
Ethanol
Surface area
Calcium
Specific surface area
ethyl alcohol
calcium phosphates
washing

Keywords

  • Calcination
  • Dispersion
  • Hydroxyapatite
  • Nanocrystal
  • Sintering
  • Thermal decomposition

ASJC Scopus subject areas

  • Chemistry(all)
  • Materials Science(all)
  • Bioengineering
  • Modelling and Simulation
  • Condensed Matter Physics
  • Atomic and Molecular Physics, and Optics

Cite this

Calcination of rod-like hydroxyapatite nanocrystals with an anti-sintering agent surrounding the crystals. / Okada, Masahiro; Furuzono, T.

In: Journal of Nanoparticle Research, Vol. 9, No. 5, 10.2007, p. 807-815.

Research output: Contribution to journalArticle

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