Influence of polymer latex on the setting time, mechanical properties and durability of calcium sulfoaluminate cement mortar

Abstract

In this study, three different types of polymer latexes (styrene butadiene rubber (SBR), styrene acrylic ester (SAE) and polyacrylic ester (PAE)) with three different dosages (0%, 10% and 20%) were employed to prepare polymer latex modified calcium sulfoaluminate (CSA) cement mortar based on the same workability. The setting time, mechanical properties including strength, shrinkage, weight loss, water capillary adsorption, anti-penetration property and durability properties such as resistance to freeze-thaw cycle, carbonization and sulfate attack were measured. The experimental results show that polymer latexes perform good water-reduction effect and delayed setting behavior on CSA cement mortar. Meanwhile, polymer latexes are helpful to enhance the mechanical properties of CSA cement mortar. Generally, SBR latex modified mortar performs the best properties in terms of strength, weight loss, water capillary adsorption and anti-penetration property. Addition of polymer latex decreases strength when subjected to extreme conditions, however, polymer latex modified mortars perform good resistance to carbonization and sulfate attack, although only SBR latex improves the freeze-thaw cycle resistance.