Effect of boric acid and triethanolamine compound on early hydration properties of magnesium potassium phosphate cement

To enhance the early performance of magnesium potassium phosphate cement (MKPC) and compensate for loose of compressive strength caused by the addition of boric acid (BA), triethanolamine (TEA) was incorporated in this work. This research was demonstrated that TEA hindered the dissolution of MgO and formed a complex with potassium ions, as evidenced by tests including compressive strength, hydration heat analysis, microstructure analysis, conductivity, and ion concentration. Furthermore, the study demonstrated that the addition of 2 wt% BA and 2 wt% TEA to MKPC resulted in a significant improvement in its characteristics, while only minimally affecting its early compressive strength. The compound was found to extend the setting time and enhance fluidity by 200 % and 32 % respectively, while also inhibiting the formation of K-type struvite. The hydration product type of MKPC did not change, and MKPC can reach an early compressive strength of 42.52 MPa at 24 h, only experiencing a slight reduction of 1.78 %.