The in- and out-of-plane fracture behaviour of injection-moulded discontinuous long glass fibre reinforced (DLGF) polypropylene composites (PP) as stu.died. The DLGF content (0-11 wt%) and thickness of the molded plaques were vaned. The m-plane fracture toughness, as assessed by the essential work of fracture (EWF) method, showed a clear anisotropy. This was explained by the effects of the DLGF orientation and distribution. confirmed by fractography. The out-of-plane instrumented falling weight impact (IFWI) toughness ofthe 4 mm thick plaques was higher than that of the 2 mm thick ones. This was attributed to the onset of shear fracture, supported by the DLGF alIgnment across the plaque thickness in the thicker plaques.
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