Effect of polycarbonate for preparation of mesophase pitch via co‑carbonization and their resulting high-performance carbon fibers

Abstract

Framing high-performance carbon fiber (HPCF) requires mesophase pitch (MP) having an adequate amount of anisotropic content with excellent orientation and melt flow structure. Typically, MP formation requires high temperature to generate free radicals, which has prompted the quest for low-energy consumption approaches. This study disclosed a simple and cost-effective method for synthesizing highly spinnable MP via co‑carbonization of coal tar pitch (CTP) with polycarbonate (PC). Initially, PC (0–25 wt%) was melded into CTP to prepare various isotropic pitches (IP), which were further transformed into MPs by treating at 400 °C for 4 h. After analysis, 15 wt% PC appeared efficacious for anisotropy generation and to achieve MP with requisite properties for HPCF, conditions were further optimized (400–410 °C for 4–6 h). To ascertain the suitability, MP-15-405-5 exhibiting superior characteristics was transformed into pitch fibers, stabilized, and subsequently carbonized at 1000 °C to produce carbon fibers (CF). The resulting CF exhibited excellent mechanical properties with tensile strength and tensile modulus of 1.41 GPa and 156.25 GPa, respectively. The study suggests that PC acts as a dominant module in manufacturing high-quality spinnable MP and improves the yield of anisotropic content at relatively lower experimental conditions, making the process more efficient and cost-effective.