FWCNT-templated carbon fibers from a high carbonization yield, solution-processable p-phenylene

Abstract

Current carbon fiber manufacturing relies heavily on polyacrylonitrile (PAN) precursors, which suffer from energy-intensive processing and limited carbon yields (∼50 %). Here, we demonstrated a solution-processable poly(benzophenone) (PBP) precursor system that bypasses oxidative stabilization while achieving exceptional carbonization yields of 74 % at 1000 °C. The rigid-rod aromatic structure of PBP provides thermodynamic favorability toward graphitic transformation, while benzophenone linkages enable solubility in aprotic solvents for continuous wet-spinning. Strategic incorporation of few-walled carbon nanotubes (FWCNTs) at 0.25–1.0 wt % creates a templated carbonization pathway through non-covalent π-π interactions between aromatic polymer chains and nanotube sidewalls. This FWCNT-guided structural evolution enhances graphitic ordering (ID/IG ratio changed from 0.89 to 0.71), promotes anisotropic carbon domain growth, and delivers concurrent improvements in mechanical, electrical, and thermal properties. Optimized PBP precursor with 1 wt % FWCNT (P-CNT-1.00) derived carbon fibers achieved tensile strength of 397 MPa, Young's modulus of 93 GPa, electrical conductivity of 207 S cm−1, and thermal conductivity of 19.5 W m−1 K−1, which represents a 1.3, 3.4, 1.7, and 4.8-fold improvements over pristine PBP, respectively. This molecularly engineered approach demonstrates the feasibility of solvent processable aromatic polymer as a practical carbon fiber precursor that not only shows higher carbonization yield and energy efficiency, but also can be further enhanced via FWCNT incorporation.