Wettability comparison of argon and oxygen plasma treatment for coconut fiber with 2 MHz RF plasma system

Abstract

The use of natural and environmentally friendly materials is increasingly being developed. Natural reinforcement like coconut fiber is used for composite known as green composite materials. The surface of the coconut fiber has a low surface energy and is hydrophobic, so the interfacial adhesion with the matrix is weak. Modifying the surface of the fiber is a common treatment. This work is concerned with the influence of the plasma treatment on the wettability of coconut fiber using argon and oxygen plasma, with varied RF voltage of plasma system at 80, 100, 120, and 140V, respectively. The wettability of the fiber was measured by using the contact angle (CA) measurement. After the plasma treatment, the surface properties of coconut fiber were changed from hydrophobic to hydrophilic. The intensity of the plasma system was influenced by the RF voltage. The results showed that the rise of oxygen plasma treatment RF voltage caused the decrease of contact angle, whereas higher RF voltage argon plasma increased the contact angle.