Effect of 5-phase seed crystal on the mechanical properties and microstructure of magnesium oxychloride cement

In this research, the effects of synthesized 5-phase seed crystals [5Mg(OH)2·MgCl2·8H2O] on the compressive strength, reaction process, and microstructure of the two kinds of MOC system were investigated. The results show that the addition of 5-phase seed crystals can significantly increase the formation rate of 5-phase in the MOC, which can improve the compressive strength of MOC, especially in its early stage; The compact microstructure not only improves compressive strength but also increases water resistance. Moreover, the effect of seeds in improving compressive strength and water resistance is more noticeable in the MOC system with phosphoric acid.