The setting reactions and thermal degradation of the phosphate binders are interpreted from the DTA and X-ray diffraction data. Setting takes place through complex formation of (NH4Mg PO4.6H2O)n, excess reactants, and water. Dehydration and thermal reactions lead to a sequence of reactions forming (NH4MgPO4.H2O) n, (Mg2P2 O7)n', Mg2P 2O7, and Mg3(PO4)2.
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