Comparative study on monitoring structural damage in fiber-reinforced polymers using glass fibers with carbon nanotubes and graphene coating

This paper reported the preparation of glass fibers (GFs) with carbon nanotubes (CNTs) and graphene coating by using an electrophoretic deposition (EPD) process. The developed GFs were embedded into epoxy to illustrate the role of different coatings on monitoring the damage in fiber reinforced polymers (FRPs). Piezoresistive effects of GFs with different coatings and corresponding composites were studied and compared. The results showed that GFs with both coatings exhibited a negative temperature coefficient behavior, and graphene coated sample was more sensitive to temperature and strain than that of CNTs. Huge dissimilarities on piezoresistivity of FRPs were also observed when the samples were subjected to the mechanical loading, which originated from the different interphases generated between the fibers and polymer matrix. GFs with graphene coating provided more details on the damage accumulation in FRPs and could be more practical for the early warning of structural damage in FRPs.