Study on Interfacial Strength Properties between PBO Fiber Modified by Oxygen Plasma Treatment and Epoxy Resin
Tomo NAKAMURA, Takashi MATSUOKA and Kazuhiko SAKAGUCHI
Abstract:The effect of oxygen plasma treatment under various treatment power and time on the interfacial strength properties between PBO fiber and epoxy resin was examined. Microdroplet test was conducted to measure the interfacial shear strength (IFSS) between the fiber and the resin. To investigate how the physical and chemical effect of the treatment on the increase in IFSS would change with change of the treatment conditions, the microdroplet test on the aging specimens left more than 20 days was also performed. Furthermore, the interlaminar shear test employing short beam shear method and the static tensile test were conducted in order to investigate the effect of the plasma treatment on the mechanical properties of PBO fiber reinforced plastics (PBO-FRP). The experimental results show the main conclusions as follows. (1) Oxygen plasma treatment increased the IFSS with an increase of the treatment power and time. (2)It was clarified that the physical effects of oxygen plasma treatment caused by the etching such as an increase in the surface area and the anchor effect on the treated fiber mainly improved the IFSS. (3)Oxygen plasma treatment increased the interlaminar shear strength by up to about 76% compared with non-treatment specimens. (4) Oxygen plasma treatment improved Youngfs modulus of PBO-FRP by up to about 25% while tensile strength of PBO-FRP was slightly decreased due to the damage of PBO fiber caused by the etching. Key Words:PBO fiber, Oxygen plasma treatment, Interfacial shear strength, Interlaminar shear strength, Tensile strength