Effects of hydroxyethyl cellulose and oxalic acid on the properties of cement

Effects of hydroxyethyl cellulose (HEC), oxalic acid and their binary mixtures {1:1, 1:2, 1:3 and 1:4 (by mass)} on the properties of ordinary Portland cement have been studied using up to 4% admixtures. Variations in setting time, heat of hydration, strength, hardness and fracture toughness have been determined. FT-IR and XRD have been utilized to determine the phase compositions of the material. Corrosion resistance against H 2SO 4, HCl and seawater has been studied by determining the loss in mass of cement mortars. It was found that HEC acts as a retarder and oxalic acid as an accelerator. The binary mixture (1:3) has increased the heat of hydration, strength, hardness, fracture toughness and corrosion resistance. Interaction between HEC, oxalic acid and cement hydration products takes place, and new phases are formed in the presence of water, which lead to the formation of stronger bonds and the sealing of the pores in the resulting product causing decreased water absorption as compared to ordinary Portland cement.