Effect of calcined nanoclay on microstructural and mechanical properties of chemically treated hemp fabricreinforced cement nanocomposites

Abstract

Calcined nanoclay was prepared in this paper by heating nanoclay (Cloisite 30B) at 900° C for 2h. This study presents the influence of calcined nanoclay (CNC) and chemical treatment on the microstructure and mechanical properties of treated hemp fabric-reinforced cement nanocomposites. Characterisation of microstructure is investigated using Quantitative X-ray Diffraction Analysis (QXDA) and High Resolution Transmission Electron Microscopy (HRTEM). The optimum hemp fabric content is 6.9 wt% (i.e. 6 fabric layers). Alkali treated hemp fabric-reinforced cement composites exhibited the highest flexural strength and fracture toughness when compared to their non-treated counterparts. In addition, mechanical properties are improved as a result of CNC addition. An optimum replacement of ordinary Portland cement with 1 wt% CNC is observed through reduced porosity and increased density, flexural strength and fracture toughness in treated hemp fabric-reinforced nanocomposite. The microstructural analysis such as QXDA indicates that the CNC behaves not only as a filler to improve the microstructure, but also as the activator to support the pozzolanic reaction and thus improved the adhesion between the treated hemp fabric and the matrix.