• A novel synthetic pitch was prepared via chlorine- and nitrogen-induced substitution polymerization using chloromethyl naphthalene and quinoline, enabling molecular-level structure control.
• Pyridinic nitrogen in quinoline acts as an effective active site, coupling with chlorine-containing aromatics to drive polymerization and oligomerization.
• Optimizing reaction temperature and time increases polymerization degree, raising the softening point to 258.6 °C, yielding a highly spinnable pitch.
• Carbon fibers derived from this pitch achieved a tensile strength of 1163.82 MPa, demonstrating a simple, safe route to high-performance isotropic pitch-based carbon fibers.