High conductivity electrospun carbon/graphene composite nanofiber yarns

Abstract

Polyacrylonitrile/graphene (PAN/GP) composite nanofiber filaments were spun continuously by a homemade eight‐needle electrospinning device with an auxiliary electrode, and then, yarns were obtained by plying and successive twisting. Subsequently, the composite yarns were stabilized at 250–280°C for 1–2 h and then carbonized at 800–1100°C for 1–3 h. The diameter of yarns significantly decreased by over 60% after carbonization and the structure became more compact. The optimum stabilization conditions were at 270°C with holding for 1.5 h. The addition of GP at a low mass fraction (<1%) promoted the formation of ladder‐like structures and ordered graphitic structures during stabilization and carbonization. It seems there were defects in the pristine CNF, and the addition of GP reduced the defects. The conductivity of the composite CNF yarn sharply increased with the increase of GP content to 1%, and then decreased. The maximum value was 66.44 ± 13.16 S/cm at 1100°C held for 3 h. The mechanical properties for composite CNF yarns were performed. The maximum stress and modulus were 59.49 MPa and 14.63 GPa, respectively. POLYM. ENG. SCI., 58:903–912, 2018. © 2017 Society of Plastics Engineers