Preparation and performance evaluation of dextrin-modified slow-release hydration heat inhibitor

Abstract This study aims to mitigate thermal cracking in mass concrete, a phenomenon resulting from heat release during cement hydration. To this end, a novel hydration heat inhibitor was prepared by modifying dextrin through esterification and polymerization with acrylic acid. The inhibitor, abundant in hydroxyl and carboxyl groups, is slowly released within cement’s weakly alkaline environment. Once released, it adsorbs onto cement particles, leading to a significant increase in the absolute ζ -potential of the paste. The inhibitor effectively retards the hydration process, achieving a temporary delay in the occurrence time of the temperature peak and a significant 20.33 °C reduction in the peak temperature. Additionally, it prolongs the initial and final setting times by 197 min and 245 min, respectively. While it exhibits a temporary inhibitory effect on the compressive strength at early ages (3 days and 7 days), the 28-day compressive strength is improved by approximately 7 %. This study has prepared and tested a cement hydration heat inhibitor, which can realize the regulation of hydration heat and the enhancement of compressive strength in the application of mass concrete.