Abstract
A complete set of experiments was carried out to investigate the fracture behaviour of continuous glass fibre-reinforced polypropylene composites and the corresponding polypropylene resin. Mode I and mode II interlaminar critical strain energy release rates are reported for this material for the first time. The test results show that both mode I and mode II critical strain energy release rates of the glass/polypropylene composites are much higher than those of traditional epoxy composites. However, the increase of fracture toughness from mode I to mode II is not as large as that reported for epoxy composites. The fibre volume fraction is also lower in the glass/polypropylene composite system studied. Scanning electron micrographs (SEM) show extensive plastic deformation on both mode I and mode II delamination fracture surfaces, suggesting that the plastic deformation is probably the most important energy dissipation mechanism during the interlaminar fracture process in these materials.