In ready-mixed mortar, the addition amount of hydroxypropyl methylcellulose is very low, but it can significantly improve the performance of wet mortar and is a major additive that affects the construction performance of mortar. Reasonable selection of hydroxypropyl methylcellulose of different varieties, different viscosities, different particle sizes, different viscosity degrees and addition amounts has a positive impact on the improvement of the performance of dry mortar.
Water retention of hydroxypropyl methylcellulose
Water retention of hydroxypropyl methylcellulose: In the production of building materials, especially dry mortar, hydroxypropyl methylcellulose plays an irreplaceable role, especially in the production of special mortar (modified mortar), it is an indispensable part.
The important role of hydroxypropyl methylcellulose mainly has three aspects,
One is excellent water retention capacity,
The second is the effect on the consistency and thixotropy of mortar,
The third is the interaction with cement.
The higher the viscosity of hydroxypropyl methylcellulose, the better the water retention performance.
Setting retardation of hydroxypropyl methylcellulose
Setting retardation of hydroxypropyl methylcellulose: The function of cellulose ether is to delay the hydration process of cement. Cellulose ether imparts various beneficial properties to the mortar, and also reduces the early hydration heat release of cement and delays the hydration kinetic process of cement.
With the increase of hydroxypropyl methylcellulose addition, the setting time of mortar increased significantly.
In summary, in ready-mixed mortar, hydroxypropyl methylcellulose plays the role of water retention, thickening, delaying cement hydration power, and improving construction performance. Good water retention capacity makes cement hydration more complete, which can improve the wet viscosity of wet mortar, improve the bond strength of mortar, and can adjust the time.