Thermokinetic Investigation of the Drying Conditions on Amorphous Calcium Phosphate
The present work investigated dried calcium phosphate powders which still retain an amorphous or poorly crystalline structure under a variety of conditions. In previous studies, freeze- drying was found to be the optimum drying condition. However, several publications, as well as our previous studies, have shown that calcium phosphate amorphous, or a poorly crystalline structure, can retain their structure even if the samples are dried immediately after synthesis up to 200oC. In our study, we used the thermokinetic studies FTIR and XRD and showed that the samples are amorphous, or poorly crystalline, but were unable to answer the questions: Is there a difference between the differently dried amorphous calcium phosphates? What are the optimum drying conditions under which the amorphous calcium phosphate (ACP) structure loses the physically bounded water, but still retains the chemically bounded water?
Date
15.11.2017.
Keywords
amorphous calcium phosphate, chemisorbed water, physisorbed water, FTIR-PAS, DTA/TG, activation energy, Arrhenius plot
DOI
10.4028/www.scientific.net/KEM.758.204
Hyperlink
https://www.scientific.net/KEM.758.204
