Examining the effects of UV radiation on the physical and tensile properties of TiO2 functionalized Kevlar fiber reinforced epoxy composites

Abstract

ABSTRACT Kevlar fiber is a widely utilized fiber with applications in the aerospace, automotive, athletic, wind energy, medicinal, optical, and defensive fields. Kevlar fiber reinforced composites, unfortunately, are constrained in their development by weak interfacial adhesion with polymer matrix and fiber degradation in the presence of UV light. Both the polymeric epoxy matrix and the Kevlar fibers lose some of their mechanical qualities when exposed to UV radiation. Surface modification of the reinforcement fibers is one of the effective ways to improve the mechanical performance of fiber-reinforced composites. In order to enhance the Kevlar fibers resistance to UV deterioration, the fiber was hydrothermally (HT) treated with UV absorber Titanium Dioxide – nano particles (TiO2-np) after being acid functionalized with hydrochloric acid. The modified fibers and epoxy resin were combined during the compression molding process to fabricate the Kevlar Fiber Reinforced Composite (KFRC). The physical and chemical properties of modified KFRC before and after UV treatment were examined using UV-Visible and Fourier Transform Infrared spectroscopy. Scanning Electron Microscope micrographs have evidenced that the TiO2-np layer was successfully deposited onto the surface of the Kevlar fiber. It was also observed that after 180 hours of UV exposure, the average Young’s modulus of unmodified KFRC dropped by 21.9%.