1. Hydroxypropyl methyl cellulose soluble in cold water, hot water dissolved will encounter difficulties. But its gelation temperature in hot water is significantly higher than that of methyl cellulose. The solubility of methyl cellulose in cold water is also greatly improved.

2. The viscosity of hydroxypropyl methyl cellulose is related to its molecular weight, and the larger molecular weight is the higher viscosity. Temperature will also affect its viscosity, temperature increases, viscosity decreases. However, the viscosity of high temperature is lower than that of methyl cellulose. The solution is stable when stored at room temperature.

3. Hydroxypropyl methyl cellulose is stable to acid and alkali, and its aqueous solution is very stable in the range of pH=2~12. Caustic soda and lime water have no great effect on its properties, but alkali can accelerate its dissolution rate and improve the viscosity of the pin. Hydroxypropyl methyl cellulose has stability to general salts, but when the concentration of salt solution is high, the viscosity of hydroxypropyl methyl cellulose solution tends to increase.

4. The water retention of hydroxypropyl methyl cellulose depends on its adding amount, viscosity, etc. The water retention rate under the same adding amount is higher than that of methyl cellulose.

5. The adhesiveness of hydroxypropyl methyl cellulose to mortar construction is higher than that of methyl cellulose.

6. Hydroxypropyl methyl cellulose has better enzyme resistance than methyl cellulose, and the possibility of enzymatic degradation in solution is lower than methyl cellulose.