Enhanced interfacial properties of domestic aramid fiber-12 via high energy gamma ray irradiation

The high energy irradiation was used to modify domestic aramid fiber-12 (DAF12) in epoxy chloropropane. The properties of the interphase between DAF12 and epoxy matrix systems were optimized. Scanning electron microscopy was employed to characterize the surface morphology of DAF12 and high energy irradiated fibers (HEI-DAF12) and composites de-bonding section. Atomic force microscopy showed the original smooth surface disappeared. Single fiber pull-out tests revealed that the interfacial shear strength of HEI-DAF12/epoxy composite was substantially improved by 45.17% after irradiation in 400 kGy dose. Dynamic contact angle analysis indicated the increased total surface free energy. The changes of elemental composition investigated via X-ray Photoelectron Spectrometer verified the increase polar groups on fiber surface caused by high energy irradiation.