Structural Observation Of Cement Paste Modified With Hydrophobic Organoclay

This study investigates the impact of different hydrophobic organically modified clay (OC), grouped according d am and functional group of modifier, on hydration, microstructure, mechanical and water absorption properties of cement formulations. SEM, TGA, XRD and N-2 sorption techniques employed for microstructural characterization. Pore and pore neck size distribution of cementitious materials was derived from QSDFT method applied on sorption isotherms. Results revealed that in OC-cement formulations the volume and the width of small capillary pores varies depending on the modifier type and d(001) of OC, meanwhile the distribution of pore neck size is almost the same for all compositions. According to results, cement compositions with the addition of OC possessing aromatic substitute group and of larger d(001) showed higher mechanical strength and substantially lower sorptivity. (C) 2020 Elsevier Ltd. All rights reserved.