Magnesium Phosphate Cement Derived from Ammonium Polyphosphate

4 Magnesium Phosphate Cement Derived from Ammonium Polyphosphate 

Ammonium polyphosphate solution (APP) contains about 44% water and is known commercially as Poly-N. The major constituents of APP are pyrophosphate, along with small amounts of tri- and tetrapolyphosphate. These 

The reaction between APP and hard-burned MgO is strongly exothermic, with the cement setting within 3 min. The early strength of the cement was 13.8 MPa (2000 psi) after 1 h and over 20 MPa (2900 psi) after 5 h (Sugama and Kukacka, 1983b). Struvite was identified as the major cementitious phase by X-ray diffraction. 

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