Study of mechanical properties of basalt fibers/epoxy composites containing silane-modified nanozirconia

Abstract

Epoxy matrix composites owing to their outstanding properties such as high strength, low weight, high thermal stability and good stiffness are broadly utilized in various industries. Also, the basalt fibers as a green industrial material show various extraordinary properties such as high mechanical strength, desired stability, suitable chemical resistance, and high temperature resistance. In this study, the effect of silane-modified nanozirconia on the tensile and flexural properties of basalt fibers/epoxy composites is investigated. As a first step, the surface of nanozirconia was modified with a silane coupling agent namely 3-methoxysilyl propyl amine. Fourier transform infrared (FT-IR) spectroscopy has been used to demonstrate the chemical nature of the silanized ZrO2 nanoparticles prepared. 3-methoxy silyl propyl amine/nanozirconia with various loadings (0, 1, 3 and 5 wt.%) were added to the epoxy resin via mechanical and ultrasonication routes. The resultant mixtures were then utilized to fabricate ZrO2/satin texture basalt fibers/epoxy nanocomposites using hand-layup technique. This symptomatic behavior exposes the successful modified ZrO2 nanoparticles to enhance the interfacial bonding. Also, a scanning electron microscope (SEM) was used to study the distribution level of silanized ZrO2 nanoparticles in the matrix as well as the fracture surfaces of the specimens. Experimental results from three-point bending and tensile tests showed that with the dispersion of 3 wt.% nanozirconia, flexural strength, flexural modulus, flexural failure strain, tensile strength, tensile modulus and tensile failure strain enhanced by 90, 74, 84, 76, 85 and 14%, respectively, compared with specimens without nanozirconia. The SEM observations of the fracture surfaces of the nanocomposites clearly indicated that the enhancement in the flexural and tensile properties was due to the improvement in the interfacial adhesion between the basalt fibers and modified ZrO2 nanoparticles-enhanced epoxy matrix.