Effect of glass nanofibers on mode I interlaminar fracture toughness of glass/epoxy composites

The idea of using glass nanofibers was proposed to overcome the weakness of out-of-plane properties of glass/epoxy composites. Glass nanofibers were produced by electrospinning solution of tetraethyl orthosilicate and polyvinylpyrrolidone as carrying polymer and dispersing the nanofibers in resin using an ultrasonic mixer. Various percentages of glass nanofibers were mixed with the resin and its effect on the tensile properties was investigated. Based on the tensile strength, the optimal percentage of nanofiber in the matrix was optimized. Finally, the hybrid composite was produced with unidirectional glass fabric using the optimized glass nanofibers content in resin. Interlaminar fracture toughness in mode I test was performed to investigate the effect of the addition of glass nanofibers on composites' mechanical properties. Results showed a significant increase (up to 91%) in interlaminar fracture toughness at the crack initiation state and caused a slight increase in the crack propagation load.