Influence of organosilicon admixtures on the hydration of Portland cement

Abstract The impact of three different organosilicon compounds: poly(dimethylsiloxane) (PDMS), potassium methylsiliconate (MESI) and triethoxyoctylsilane (OTES), used as integral admixtures, on Portland cement hydration has been investigated by isothermal calorimetry DTA-TG analysis. silicon-based compounds are widely internal hydrophobic agents added into batch water; therefore, their effectiveness was means capillary water absorption test. to measure the rate amount heat released during ordinary with admixtures at 20 °C, 30 40 °C 50 °C. It allowed determine activation energy well. results indicate that (except MESI admixture) decrease in release hydration. In addition, it is noticeable addition admixture significantly prolongs induction period delays contrast OTES PDMS-based does not affect significant energy. analysis had shown differences between reference sample samples containing thermal decomposition, terms moisture bound water, well Ca(OH) 2 or carbonates. presented this paper enable a better understanding interactions matrix. study shows effect thus potential final properties cement-based material.