Potential strengthening additive for cement mortar based on the maleic anhydride - α-octene functionalised multiwall carbon nanotube

Multiwalled carbon nanotubes obtained via the Catalytic Chemical Vapor Deposition method were covalently functionalised by maleic anhydride - alpha-octene copolymer via 'grafting from' approach using a sonochemical method to obtain the additive for improving the mechanical properties of cement mortar. The catalyst and oxidising agent used for nanotube synthesis and surface activation through the formation of the functional groups in a mild condition were Fe - Co / Al2O3 and potassium permanganate, respectively. These functional moieties were used for the consequent functionalization of the nanotubes with the copolymer. The instrumental techniques like Transmission Electron Microscopy, Scanning electron microscopy, Fourier transform infrared spectroscopy, X - ray powder diffraction, and Raman spectroscopy were used to characterise the obtained nanostructures. The used techniques revealed the success of the surface functionalization in the formation of the strengthening additive. The results obtained from the compressive strength tests for the strengthening additive included cement mortar composites revealed the positive effects of the additive on the mechanical properties of the cement mortar over the reference material. The use of the 'grafting from' approach to covalently functionalise the multiwalled carbon nanotubes with maleic anhydride - alpha-octene copolymer via the sonochemical method to obtain strengthening additive for cement mortar is the novelty of the work.