The physico-mechanical stability of C–S–H/polyaniline nanocomposites

The formation and characterization of various types of organically modified C–S–H-based nanocomposites have recently been investigated. The engineering properties of this class of cementitious materials, however, have rarely been studied. The current work examines a new approach to the assessment of the mechanical performance of C–S–H/polyaniline nanocomposites prepared in situ using C–S–H systems having C/S ratios of 0.8 and 1.2. Test methods including X-ray diffraction and dynamic mechanical analysis were employed in order to evaluate the physical and mechanical stability of these polymer-modified C–S–H nanocomposites. The variations in the 002 basal spacing, storage modulus (E′) and internal friction (tan δ) of the C–S–H/polyaniline nanocomposites were examined upon the incremental removal of the interlayer water. It was suggested that the polyaniline molecules may reinforce the C–S–H lamellar structure as indicated by the magnitude of the decrease in the 002 basal-spacing during the dehydration. Moreover, the initial DMA response of the C–S–H/polyaniline nanocomposites appears to be improved.