The viscosity of the hydroxypropyl methylcellulose solution depends on the following factors:
1. Molecular weight (or degree of polymerization) and concentration of cellulose ether, solution temperature, shear rate and test method.
2. The higher the degree of polymerization of cellulose ether, the larger the molecular weight, and the higher the viscosity of its aqueous solution;
3. The higher the dosage (or concentration) of cellulose ether, the higher the viscosity of its aqueous solution, but attention should be paid to selecting the appropriate dosage when using it, so as to avoid excessive dosage and affect the working performance of mortar and concrete;
4. Like most liquids, the viscosity of cellulose ether solution will decrease with the increase of temperature, and the higher the concentration of cellulose ether, the greater the effect of temperature;
Cellulose ether solutions are usually pseudoplastics with shear thinning properties. The higher the shear rate, the lower the viscosity.
Therefore, the cohesion of the mortar will be reduced due to the action of external force, which is beneficial to the scraping construction of the mortar, so that the mortar can have good workability and cohesion at the same time. However, when the concentration of cellulose ether solution is very low and the viscosity is very small, it will show the characteristics of Newtonian fluid. When the concentration increases, the solution will gradually show the characteristics of pseudoplastic fluid, and the higher the concentration, the more obvious the pseudoplasticity.
Hydroxypropyl methylcellulose produced by Landcel has a wide viscosity range and good stability. It has good application effect in various building additives.