Development And Research On Bonding Mortal With High Flexibility

The reason of the problems exposed in cement-base tile adhesives, such as imperfect bonding, caking and so on, are analyzed. The internal stress (normal stress and shearing stress) of the tile adhesive, which caused by the different deformation are calculated. The study proofs that increasing the flexibility of the adhesive mortar, can reduce the internal stress. Then through experimental investigation, develop a new cement-based tile adhesive, which has the property of nice bond strength and good flexibility.At first, the cement-sand ratio is selected. Secondly, the properties of the mortar added different polymer emulsion powder was tested, and the most suitable addition is selected. Then the physical properties of the mortar added redispersible polymer poewr, including water cement ratio, the bulk density, and fluidity, and mechanical property, consist of the compressive strength, the flexural strength, the ratio of the flexural strength to the compressive, bond strength, Young's modulus stress-strain curves, are tested. Through the systematically investigate, the optimal mixture is determined. After that, the mortar mixed with tire rubber particles single, and mixed with tire rubber particles and polymer poewr is tested. After all, the optimized amount is determined. Microstructure techniques, such as XRD, SEM are used to investigate microstructure of mortar with polymer poewr and tire rubber particles, to explain the reason of the change of the properties.Through the study, determined the cement-sand ratio of the mixture is 1:2, the amount of polymer poewr is 3%, and the tire rubber particles is 3%-5%. The result shows that the resisting shear bond strength of mortar with 3% polymer poewr forereach 2.3MPa, and the tensile bond strength is over 2.0MPa, and the elastic modulus is reduced about 50% as compared to base mortar. Added with tire rubber particles at 3-5 percent in the mixture with polymer poewr can reduce the elastic modulus further, it is lower than lOOOMPa. The calculation demonstrate the flexibility can improve the adhesive's capacity of resisting destroy caused by the different deformation of different material.