Theoretical and experimental investigation of the wet-spinning process for mechanically strong carbon nanotube fibers

Abstract

The orientation factor is significantly important for producing highly strong conductive carbon nanotube (CNT) fibers. Highly oriented CNT fibers can be obtained by the wet-spinning of CNTs in a superacid. We present a theoretical model for obtaining well-aligned CNT fibers, which may have superior properties. Our model predicts the minimum draw ratio (D-R(0)) at various Deborah numbers (De) for CNT fibers with the target orientation. In addition, the stable operation window in the De-D-R plane is predicted using linear stability analysis of the draw resonance. Our analysis suggests that a fiber with the target orientation factor can be obtained if and only if the draw ratio, D-R, is higher than D-R(0) and is within a stable operation window. The model predictions for the stability window and the effect of D-R on the properties of the fibers were confirmed by experiment.