Effect of the low

Wood fibers were treated in different plasma frequencies (radio frequency (RF) and low frequency (LF)) using oxygen (O2) for different plasma powers to increase the interface adhesion between wood fiber and high-density polyethylene (HDPE) matrix. The influence of various plasma frequencies on mechanical properties of wood fiber-reinforced HDPE composites was reported. Tensile, flexure, short beam shear tests were used to determine the mechanical properties of the composites. The interlaminar shear strength (ILSS) increased from 11.5 MPa for the untreated wood fiber/HDPE composite to 19.8 and 26.3 MPa for LF and RF O2-plasma-treated wood fiber/HDPE composites, respectively. O2 plasma treatment also improved the tensile and flexural strengths of wood fiber/HDPE composites for both plasma systems. It is clear that O2 plasma treatment of wood fibers by RF plasma system instead of using LF plasma system brings about greater improvement on the ILSS of wood/HDPE composites. Improved fiber/matrix adhesion is able to be seen in scanning electron microscopy micrographs of fracture surfaces of the wood fiber/HDPE composite