Surface Modification and Mechanical Properties Improvement of Bamboo Fibers Using Dielectric Barrier Discharge Plasma Treatment

The effect of argon (Ar) and oxygen (O(2)) gases as well as the treatment times on the properties of modified bamboo fibers using dielectric barrier discharge (DBD) plasma at generated power of 180 W were investigated. The plasma treatment of bamboo fibers with inert gases leads to the generation of ions and radicals on the fiber surface. Fourier transform-infrared spectroscopy (FTIR) confirmed that the functional groups of lignin and hemicellulose were reduced owing to the removal of the amorphous portion of the fibers by plasma etching. X-ray diffraction analysis (XRD) results in an increased crystallinity percentage. X-ray photoelectron spectroscopy (XPS) results showed the oxygen/carbon (O/C) atomic concentration ratio increased with increasing treatment time. The fiber weight loss percentage increased with increased treatment time. Scanning electron microscopy (SEM) images showed that partial etching of the fiber surface led to a higher surface roughness and area and that the Ar + O(2) gas plasma treatment provided more surface etching than the Ar gas treatment because of the oxidation reaction of the O(2) plasma. The mechanical properties of fiber-reinforced epoxy (FRE) matrix composites revealed that the F((tr))RE-Ar (30) samples showed a high tensile strength, whereas the mechanical properties of the F((tr))RE-Ar + O(2) sample decreased with increased treatment time.