Tensile and flexural properties of glass and carbon fibre composites reinforced with silica nanoparticles and polyethylene glycol

This paper attempts to show the effect of silica nanoparticles and polyethylene glycol mixture (shear thickening fluids) on tensile and flexural properties (3-point bending) of glass and carbon fibre-reinforced thermoset composite laminates. The shear thickening fluids were prepared by combination of silica nanoparticles and polyethylene glycol using various silica contents (10-20 wt%). A viscometer was used to evaluate the shear thickening characteristics and viscosity of shear thickening fluids increased by increasing the silica content. Shear thickening fluids were impregnated on the host of glass and carbon fabrics and subsequently converted to composite laminates using vacuum infusion method with an epoxy matrix. It was found that shear thickening fluids-treated carbon and glass fabric composites exhibited up to 10% and 12% higher tensile strength than neat composites whilst the tensile modulus increased about 24%. Shear thickening fluids-treated fabric composites exhibited slower damage propagation compared to brittle nature of untreated fabric composites. However, lower flexural strength with higher energy absorption (up to 27%) were obtained after using shear thickening fluids for both carbon and glass fibre composites.