Early Hydration and Strength Development in Polymer-Modified Cements Incorporating TEA–TIPA Blends

In this study, triethanolamine (TEA) and triisopropanolamine (TIPA) were combined at specific ratios to enhance the performance of amine-based grinding aids (GAs), which are commonly employed to achieve more economical and environmentally friendly cement production. The effects of TEA-TIPA blends, prepared in three different ratios, as well as TEA and TIPA used individually, were evaluated in terms of early hydration kinetics and early-age strength development. A total of 11 CEM I 42.5R cement samples, including a control sample without GA, were produced. The early hydration behavior of paste mix-tures prepared with these cements was thoroughly investigated using heat of hydration measurements, Scanning Electron Microscopy (SEM), X-Ray diffraction (XRD), Thermo-gravimetric analysis (TGA), and setting time tests. In addition, 1- and 3-day compressive strength developments of the corresponding mortar mixtures were compared. The results demonstrated that blending TIPA with TEA mitigated the low calcium hydroxide for-mation rate, delayed early hydration, and prolonged setting time associated with TEA. Moreover, the air-entraining effect typically observed with TIPA could be minimized by incorporating TEA. Among all formulations, the most favorable performance was ob-tained with a blend containing 25% TEA and 75% TIPA.