Improvement of the strength of acrylic emulsion polymer-modified mortar in high temperature and high humidity by blast furnace slag

Abstract

Polymer modification was widely used to improve the properties of construction materials. The concept of polymer modification for mortar and concrete was put forward 80 years ago. It was known that the use of polymers for modification can greatly improve the strength, adhesion, resilience, impermeability, chemical resistance and durability properties of mortars and concrete. In southern Vietnam, a tropical weather country, the environment was usually hot with high humidity. The durability of mortar or concrete coating was reduced over time in such a condition. This study examines the strength of polymer-modified mortars in high temperature and high humidity. Moreover, the results included the improvement of strength of acrylic emulsion polymer-modified mortar (PMM) by the addition of blast furnace slag. Fifteen percent cement was replaced with blast furnace slag (BFS) in a mix proportion in order to improve strength of PMM. The specimens were cured in cycles 50±2°C, RH 90±3%, for 5 hours and 20±2°C, RH 60±3 %, for 19 hours per day. The strength of PMM was measured at the age of 3, 7, 14, 21 and 28 days, 3 and 6 months and 1 year in a high temperature and high humidity cycles.