Hydroxypropyl methylcellulose HPMC can significantly improve the water retention of the mortar. When the addition amount is 0.02%, the water retention rate will be increased from 83% to 88%; the addition amount is 0.2 %, the water retention rate is 97%. At the same time, a small amount of HPMC also significantly reduces the stratification and bleeding rate of the mortar, which indicates that HPMC can not only improve the water retention of the mortar, but also significantly improves the cohesiveness of the mortar, which is very beneficial to the uniformity of mortar construction quality.
However, hydroxypropyl methylcellulose HPMC has a certain negative impact on the flexural strength and compressive strength of the mortar. With the increase of the addition amount of HPMC, the flexural strength and compressive strength of the mortar gradually decreases. At the same time, HPMC can increase the tensile strength of mortar. When the amount of HPMC less than 0.1%, the tensile strength of mortar increases with the increase of HPMC dosage. When the amount exceeds 0.1%, the tensile strength won't significantly increase. Hydroxypropyl Methyl
Cellulose HPMC also increases the bond strength of the mortar. The 0.2% HPMC increased the bond strength of the mortar from 0.72 MPa to 1.16 MPa.
Studies have shown that HPMC can significantly extend the opening time of the mortar, so that the amount of mortar falling is significantly reduced, which is very beneficial for tile bonding construction. When the HPMC is not blended, the bond strength of the mortar reduced from 0.72 MPa to 0.54 MPa after 20mins, and the bond strength of the mortar with 0.05% and 0.1% HPMC will separately be 0.8 MPa and 0.84 MPa after 20mins. When the HPMC is not blended, the slip of the mortar is 5.5mm. With the increase of the HPMC content, the slippage will continuously reduce. When the dosage is 0.2%, the slippage of the mortar is reduced to 2.1mm.
Post time: Mar-03-2022