Dual Interfacial Design of <scp>GPTMS</scp> and <scp> SiO ₂ </scp> on Carbon Nanotubes for Synergistic Enhancement of Conductivity and Corrosion Protection in Epoxy Coatings

ABSTRACT Conductive anticorrosion coatings encounter challenges in balancing electrical conductivity with long‐term barrier stability, where filler agglomeration can limit performance. Herein, we report an epoxy‐based conductive anticorrosion coating fabricated using 3‐glycidoxypropyltrimethoxysilane (GPTMS)‐modified, SiO 2 ‐modified carboxylated carbon nanotubes (denoted as GPTMS/SiO 2 /CNTs) as conductive fillers. This modification established stable Si–O–C and Si–O–Si covalent bonds, preserving the intrinsic graphitic structure and conductivity of CNTs while contributing to improved dispersion and interfacial compatibility within the resin matrix. Incorporating 4 wt% filler into an epoxy matrix yielded a coating with a volume resistivity of 289 Ω·m. After 20 days of immersion in a 10% NaCl solution, the coating maintained a low‐frequency impedance modulus of 7.762 × 10 8 Ω·cm 2 and exhibited near‐ideal capacitive behavior. Even under scratched conditions, its corrosion current density was two orders of magnitude lower than that of the pure epoxy coating. This multiscale design offers a material solution with enhanced conductivity and lasting corrosion resistance, applicable to scenarios such as electrostatic dissipation and corrosive protection in harsh environments.