The mechanism of the effect of water retaining agent for ready-mixed mortar on the setting time of mortar is a complex process involving multiple factors.
First, the main function of water retaining agent in mortar is to absorb and retain water. Through the hydroxyl groups on its molecular chain and the oxygen atoms that can absorb water molecules, it forms hydrogen bonds with water molecules in the solution, turning the free water in the mortar into bound water, thereby enhancing the cohesion of the mortar. This mechanism of action helps to improve the working performance and water retention of the mortar.
Secondly, the addition of water retaining agent has a significant effect on the setting time of mortar. When the amount of water retaining agent is appropriate, it can prolong the initial and final setting time of mortar. This is because the water retaining agent can absorb and retain water in the mortar, slowing down the evaporation rate of water, thereby providing more sufficient space and time for the growth and development of dihydrate gypsum crystals.
However, when the amount of water retaining agent is too large, it will also have an adverse effect on the setting time of mortar. Too many water retaining agent molecules will cross-link to form association complexes, resulting in a significant increase in water demand, high mortar consistency, and greatly reduced fluidity. In this case, the setting time of the mortar may be shortened because the high consistency will limit the free movement and reaction of the components in the mortar.
In addition, the effect of water retaining agent on the setting time of mortar is also restricted by other factors, such as temperature, humidity, mortar ratio, etc. Under different environmental conditions, the effect of water retaining agent may be different.
The mechanism of the effect of water retaining agent for ready-mixed mortar on the setting time of mortar is a comprehensive result, which is affected by the performance of the water retaining agent itself, as well as by multiple factors such as mortar ratio and environmental conditions. Therefore, in practical applications, it is necessary to reasonably control the dosage of water retaining agent according to specific conditions to obtain the best mortar performance and construction effect.
