Chemical durability of superabsorbent polymer (SAP) based geopolymer mortars (GPMs)

This study investigates the durability of superabsorbent polymer (SAP) based geopolymer mortars (GPMs) against acid, sulfate, and chloride attack. Nine mix formulations containing 0, 1, and 2% SAP content by weight of fly ash were prepared. All the samples were cured at 80 degrees C, followed by curing at room temperature for 24 h. The specimens were immersed in the chemical solutions of 5% hydrochloric acid (HCl), 5% sodium sulfate (Na2SO4), and 5% calcium chloride (CaCl2) for 180 days. Thereafter, the durability performance of GPMs was evaluated based on the change in weight and change in compressive strength of the specimens. Based on the results, it was deduced that SAP based GPMs were less vulnerable to chemical attack. Furthermore, deterioration effects were lower due to improved sorptivity and porosity values. The X-ray Diffraction (XRD), Fourier Transform Infrared (FTIR) spectroscopy, Scanning Electron Microscope (SEM), and Energy Dispersion X-ray Spectroscopy (EDX) analyses revealed that the inclusion of SAP improves the chemical durability of GPMs. (C) 2019 Elsevier Ltd. All rights reserved.