Fluorapatite surface energy

The surface energy of fluorapatite as compared to HA was recently determined by Wu and Nancollas using different techniques [75]. The data indicate that, whatever the technique used, FA exhibits a higher surface tension than HA (e.g. 18.5 mJ m for FA compared to 10 mJ m for HA, using contact angle... 

Surface free energies of hydroxylapatite and fluorapatite were determined by Busscher et al. (1987) from contact angle measurements. They found that in vacuum y ranges between 72 and 95 mJ/m. In the presence of a saturated vapor, y was found to be between 28 and 48 mJ/m. The difference in y obtained by the two methods was explained as resulting from the presence of an adsorbed film originating from the liquid droplets employed in the measuring procedure. Face-specific measurements revealed for the 001 crystal face y = 28 3 mJ/m, and y = 48 7 mJ/m on 100 for fluorapatite, and for hydroxylapatite the 001 crystal face y = 39 11 mJ/m, and y = 30 3 mJ/m on... 

Busscher HJ, De Jong HP, Arends J (1987) Surface free energies of hydroxylapatite, fluorapatite and calcium fluoride. Mater Chem Phys 17 553-558... 

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