Highly strong carbon fibers through synergistic carbonization process of sulfonated poly(p-phenylene sulfide) and carbon nanotube

This paper presents the fabrication and characterization of high-performance carbon nanotube-polyphenylene sulfide (CNT-PPS) composite fibers. The study begins by dissolving PPS in chlorosulfonic acid (CSA) to create dopes suitable for wet-spinning, enabling the formation of CNT-PPS composite fibers. The presence of PPS, known for its low solubility and high crystallinity, leads to improved mechanical properties and thermal stability after carbonization. The structural evolution of the fibers during heat treatment is examined. The results show that the fibers' tensile strength and modulus increase significantly after carbonization, with the highest tensile strength (6.04 ± 0.50 GPa) achieved by the fiber containing 30 wt% of PPS heat-treated at 1400 °C and the highest tensile modulus (619 ± 44 GPa) achieved by the fiber containing 10 wt% of PPS heat-treated at 2500 °C. The mechanism of radical coupling between CNTs and PPS during de-sulfonation is proposed as a key factor contributing to the enhanced mechanical properties. The study also highlights the benefits of using PPS as a carbon fiber precursor, eliminating the need for costly and time-consuming stabilization processes. Overall, this research offers a novel strategy for producing high-performance and cost-effective carbon nanotube-based carbon fibers with applications in various industries.