Influence of boric acid on the hydration of magnesium phosphate cement at an early age

International audience; Magnesium phosphate cements (MPCs) are receiving increasing attention because of their outstanding properties of fast setting and hardening, good volume stability and excellent bonding to old concrete structures. Their main area of application is thus rapid repair works, but they may also offer prospects for the stabilization / solidification of deleterious waste.The main constituents of MPCs are magnesium oxide (calcined, or hardburnt, magnesia) and a water-soluble acid phosphate, which is most often diammonium hydrogen phosphate (NH$_4$)$_2$HPO$_4$. To avoid the release of noxious gaseous ammonia during the hardening process, potassium dihydrogen phosphate (KH$_2$P…