Abstract: The fracture behavior of PE-HD/wollastonite/POE-g-MAH composites in the mixed mode region was studied using the essential work of fracture (EWF) method. The applicability of EWF method and the stress state of the samples were verified. Linear regression was used on the experimental data to obtain the EWF parameters. With increasing wollastonite contents, the essential work of fracture increased, while the non-essential work of fracture decreased. The plastic deformation capability and the fracture toughness of the composites was mainly affected by the crack propagation resistance during the necking and tearing processes after yielding. It was also found that the impact strength of the material decreased with increasing wollastonite content. The materials with high impact strength, however, had low specific essential work of fracture.

Key words: high-density polyethylene, wollastonite, ethylene-octylene copolymer, essential work of fracture, fracture behavior