Oxidation of Reclaimed Carbon Fiber Surfaces for The Improvement of Fiber/Composite Adhesion

Norazlina Mohamad Yatim, Zurina Shamsudin, Azizah Shaaban, Nurhernida Abdullah Sani, Ridhwan Jumaidin, Emy Aqila Shariff

  • Norazlina Mohamad Yatim


The recovery of carbon fiber (CF) from carbon fiber reinforced composites (CFRP) waste provide valuable reinforcement material for secondary structural application. Although surface modification of reclaimed-CF can improve its interfacial compatibility with composites, it may affect its strength and capability as a reinforcing material. This paper investigates the influence of different reflux time (10 – 50 min) on the oxidation of reclaimed-CF surfaces using nitric acid. The reclaimed-CF was recovered using a combination of nitrogen and oxygen atmospheres during pyrolysis at low final heating temperature (540°C). The surface chemical composition and morphology of the reclaimed-CF were investigated via FT-IR and SEM respectively. Microscopy analysis shows low nitric acid oxidation time (20 min) effectively removed residues of resin prior pyrolysis and produced a clean reclaimed-CF surface. Further oxidation activated the reclaimed-CF by the creation of more acidic functional groups on their surfaces. The acidic capacities increase with oxidation time without damaged the tubular reclaimed-CF structure. Overall, the optimized nitric acid treatment produced cleaner reclaimed-CF surfaces and more active sites for better interfacial compatibility between reclaimed-CF and composite matrix.

Original Research Articles