Mechanical strength and mineralogical properties of fiber-reinforced geopolymer composites with multi-walled carbon nanotubes

In this study, polyethylene (PE) fibers and functionalized multi-walled carbon nanotubes (f-MWCNTs) were used to increase the mechanical and microstructural behavior of ground granulated blast furnace slag (GGBS)-incorporated engineered geopolymer composites (EGC) i.e., GGBS-EGC. The efficacy of different compositions, specifically 0.10 % f-MWCNTs and 0.15 % PE fibers, was confirmed by means of mechanical tests. The mix was characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) techniques. The results showed that the optimal mix of 0.15 % PE fibers, 0.10 % f-MWCNTs, and 20 % GGBS achieves a compressive strength of 38.03 MPa. While f-MWCNTs enhance strength by filling micropores, excessive amounts can hinder performance. The strong bonding improves structural integrity and ductility, with significant changes observed in crystalline structure and bonding.