Self-Setting Calcium Orthophosphate Formulations: Cements, Concretes, Pastes, and Putties - Calcium Orthophosphates: Applications in Nature, Biology and Medicine - page 493

Table 5.3 List of strategies and approaches to modify reactivity of calcium

orthophosphate cements [207]

Strategy Approach Sub-approaches

1. Dissolution
rate

1.1 Change contact area
between reagent and
mixing liquid

1.1.1 Change milling
duration
1.1.2 Use nano- or micron-
sized powders

1.2 Change solubility in the
mixing liquid

1.2.1 Use more/less soluble
phase
1.2.2 Change of reaction pH

1.3 Change saturation of
the mixing liquid

1.4 Use dissolution
inhibitors in the mixing
liquid

1.5 Modify reagent surface 1.5.1 Chemical change (pre-
reaction)
1.5.2 Physical change
(dissolution pits)

2. Nucleation
rate

2.1 Use crystallization
nuclei

2.2 Change the saturation
of the reaction product in
the mixing liquid

2.2.1 Change of saturation
2.2.2 Change of end-
product solubility

2.3 Use nucleation
inhibitors

3. Growth rate 3.1 Change the saturation
of the reaction product in
the mixing liquid

3.1.1 Change of saturation
3.1.2 Change of end-
product solubility

3.2 Use crystal growth
inhibitors

Various setting time controllers (accelerators and retardants) are
used to influence the setting time. They include sodium hydrogen
pyrophosphate (Na ) and magnesium sulfate (according

to another study, ions of citrate, sulfate, and pyrophosphate are
necessary [222]), which are added in amounts <1 wt. % [350].

H P O

2 2 2 7