Factors such as air temperature, temperature and wind pressure will affect the volatilization rate of moisture in cement mortar and gypsum-based products. Therefore, in different seasons, the water retention effect of the same amount of HPMC is different.
In the specific construction, the water retention effect of the slurry can be adjusted by increasing or decreasing the amount of HPMC added. The water retention of hydroxypropyl methyl cellulose ether under high temperature conditions is an important indicator to distinguish the quality of hydroxypropyl methyl cellulose ether. Excellent HPMC series products can effectively solve the problem of water retention at high temperatures.
In high temperature seasons, especially in hot and dry areas and thin-layer construction on the sunny side, high-quality HPMC is required to improve the water retention of the slurry. High-quality HPMC has very good uniformity. Its methoxy and hydroxypropoxy groups are evenly distributed along the cellulose molecular chain, which can improve the ability of the oxygen atoms on the hydroxyl and ether bonds to associate with water to form hydrogen bonds , So that the free water becomes bound water, thereby effectively controlling the evaporation of water caused by high temperature weather, and achieving high water retention.
High-quality cellulose HPMC can be uniformly and effectively dispersed in cement mortar and gypsum-based products, and wrap all solid particles, and form a wetting film. The water in the base is gradually released over a long period of time. The condensed material undergoes hydration reaction to ensure the bonding strength and compressive strength of the material. Therefore, in high-temperature summer construction, in order to achieve the effect of water retention, high-quality HPMC products must be added in sufficient quantities according to the formula, otherwise, insufficient hydration, reduced strength, cracking, hollowing and falling off caused by excessive drying will occur. It also increases the difficulty of construction for workers. As the temperature decreases, the amount of HPMC added can be gradually reduced, and the same water retention effect can be achieved.
Post time: Apr-25-2020