Improvement of Interlaminar Fracture Toughness in Glass Fiber Reinforced Plastic Laminates with Inorganic Nanofiber Sheet Interleaf

The present study developed a new type of nanofibrous structure-TiO₂ nanofiber sheets (TNFS) to increase the interlaminar fracture toughness of glass fiber reinforced polymer (GFRP) laminates. SEM was employed to characterize the nanofibers before and after calcination. In order to quantify TNFS, the thickness and the crevice area of TNFS were analyzed, the results showed that the thickness and the proportion of crevice area were increased with the increase of TNFS contents. Mode I and Mode II interlaminar fracture toughness were investigated for GFRP laminates toughened by different mass fraction of TNFS. The highest Mode I fracture toughness value achieved by inserting 5 wt.% TNFS in the interleaf. G_Ic value was 74.35 % higher than those of base GFRP laminates. Meanwhile, with 6 wt.% addition of TNFS, the GFRP laminates showed the highest Mode II fracture toughness, which is 60.76 % higher than those of base GFRP laminates. The improvement mechanism of toughness was illustrated by the fracture surface analysis of TNFS interlayered laminates.