Application of hydroxypropyl methylcellulose in self leveling field
The self leveling sand award is mainly a special dry mixed mortar product with leveling and self compacting function. Its self compacting and self leveling ability is very important for achieving a seamless and smooth ground layer. For a good self leveling product, it must first have appropriate operating performance and be able to maintain its overall leveling performance and self-healing ability within the construction time, In this way, the mortar is required to fully ensure its stability and uniformity within this time period. Secondly, the mortar should also have a certain strength, including bearing capacity and adhesion to the base surface. These are the basic conditions for the normal application of self leveling materials. The realization of self leveling requires the addition of hydroxypropyl methylcellulose ether, It can thicken and increase viscosity, and has the characteristics of high water retention and prolonging construction time.
The higher the viscosity of hydroxypropyl methylcellulose, the better the viscosity of modified cement-based materials. However, if the viscosity is too large, it will affect the fluidity and operability of materials. In addition, the thickening effect of hydroxypropyl methylcellulose can also increase the water demand of cement-based materials, so as to improve the output of mortar. Self leveling mortar and self compacting concrete with high fluidity require low viscosity of hydroxypropyl methylcellulose. Cellulose ether with low viscosity can play a good role in suspension, prevent slurry settlement, and also has the function of bleeding. It can ensure that it will not affect the flow effect of self leveling sand slurry. It is easy to construct and has the characteristics of high water retention. It can make the surface effect after leveling better, reduce the shrinkage of mortar and avoid peeling cracks.
Hydroxypropyl methylcellulose is widely used in various building materials. When it is used in self leveling mortar, it has the following characteristics:
1. High water retention performance can prolong the operation time of self leveling mortar, improve the durability of mortar, increase its bonding strength, excellent wet bonding performance and reduce floor ash.
2. It has strong compatibility and is suitable for all kinds of building materials and self leveling mortar to reduce sedimentation time, reduce its drying shrinkage, and avoid cracking and bulging of wall and ground.
3. Prevent bleeding, which can play a better role in the suspension, prevent slurry deposition and better bleeding performance.
4. Maintain good fluidity. The low viscosity of hydroxypropyl methylcellulose will not affect the flow of slurry, which is easy to construct. The specific good water retention performance can produce good surface effect after self leveling and avoid cracking and bulging. The stable bonding performance of cellulose ether fully ensures good fluidity and self leveling ability, Controlling the water retention rate can make it solidify rapidly and reduce shrinkage and cracking.