Influência dos polímeros superabsorventes nas propriedades físicas e mecânicas de argamassas

Abstract

The search for improvements in the durability of cementitious materials used in civil construction has motivated the use of superabsorbent polymers (SAPs) as an alternative to minimize certain problems. SAPs are materials capable of capturing and storing large amounts of water, acting as internal curing agents and assisting in the hydration reactions of cement. The methodology of this work was experimental in the laboratory, with a quantitative research approach, in which the data collected through tests were statistically compared. The study was conducted using tests for consistency index, capillary and immersion absorption, density, void index, and flexural and compressive strength. A total of 27 specimens were molded, using 3 different mortar mixes, and the specimens were analyzed at 28 days of curing. The study found that the use of SAPs in mortars contributed to an increase in porosity at early ages, which can be attributed to the additional water needed to maintain the workability of the mixtures. The presence of SAP B provided a 25.68% increase in water absorption and a 19.26% increase in the void index compared to the reference mix (REF). This corroborated the reduced compressive strength by 7.94%. On the other hand, neither capillary absorption nor density properties showed a significant difference with the presence of SAPs in the mixes. Therefore, it is suggested that the addition of SAPs can influence the physical and mechanical properties of mortars at early ages (up to 28 days). However, studies at later ages are recommended to ascertain whether pore clogging occurs and, consequently, a gain in strength.