Dry-mixed mortar has been widely used nowadays. There is a bond strength index in Dry-mixed mortar. From the physics point of view，when an object wants to attach to another object, it needs its own viscosity, the same is true for mortar. Cement is mixed with sand and water to achieve initial bond strength, and then cured by additives and cement to finally achieve the required bond strength of the mortar. So what are the factors that affect bond strength?
The effect of additives
The role of cellulose ether is mainly used to increase water retention and improve the workability of mortars. When plastering walls, it can be easily constructed like putty, and the thickness can also be controlled and reduced. The biggest advantage is that the drying speed of the mortar can be effectively controlled, and cement can be fully hydrated.
The polymer powder used in the mortar is generally water-soluble redispersible polymer powder, which can be divided into rigid and flexible. Its main function is to provide excellent adhesion, which helps to improve the water resistance, plasticity and flexibility of the mortar.
The shrinkage of the mortar can affect the actual bonding area, resulting in hollow cracks and direct loss of bond strength. Therefore, we must have strict requirements on the grading of cement and sand in the mortar, which can not only control shrinkage, but also contributes to the bond strength of the mortar.
Contact Person: Mrs. Lannie Zhang