Mechanical Performances of Wood Polypropylene Composite due to Extended Moisture Immersion

Abstract

Mechanical properties of an extruded wood polypropylene composite that was soaked in both osmotic water and artificial seawater were tested and compared in dry, wet, and redried states. Water did influence the material's flexural, compressive, and tensile strength and chord modulus after 13 months immersion. Flexural and compressive properties of the unsaturated specimens soaked in seawater were degraded slower than those of the specimens soaked in osmotic water. There was a significant effect of water type on tensile modulus of elasticity. Both nonreversible damage and recoverable portion of the material from dry to wet and then to redried state were observed for most of the mechanical properties. Results also indicated that impact strength was not affected by water immersion and redrying.