Influence of Cellulosic Additives on Tricalcium Silicate Hydration:  Nuclear Magnetic Resonance Relaxation Time Analysis

This paper reports a study on the effects of cellulose additives on the setting process of tricalcium silicate (C 3 S) paste. Cellulose and cellulose derivatives are largely used in the cement industry due to their excellent water carrying capacity that makes these additives essential in the practice of the extrusion processes. However, how they are effective in many processes is not known. We addressed this point investigating the hydration kinetics of C 3 S in the presence of cellulose derivative by thermal analysis and water proton NMR relaxation. Both these methods provided useful information on the mechanisms of the C 3 S curing process involving cellulose. The experimental results clearly show that cellulose additives act as a regulator of water release during the whole hydration process. A quantitative description of this process is reported.