ABSTRACT
Owing to its unique two-dimensional (2D) nanostructure, excellent optical property, corrosion resistance, catalytic activity and thermal stability, 2D graphic carbon nitride (g-C3N4) shows broad application prospects in various fields, such as sensing materials for the semiconductor industry, biological imaging, photocatalysis and so on. Recently, g-C3N4 has been found potential applications in fabricating high-performance flame-retardant polymer nanocomposites. Because of its inert feature and strong van der Waals forces among g-C3N4 sheets, it is essential to improve the dispersion of g-C3N4 by surface functionalization, including covalent and noncovalent functionalization. In addition, pristine g-C3N4 exhibits undesirable flame-retardant efficiency and is usually combined with conventional flame retardants to realize highly efficient flame-retardant polymeric nanocomposites. To date, numerous 2D g-C3N4-based nano flame-retardant systems, such as organic flame-retardant-functionalized g-C3N4, inorganic/g-C3N4 hybrids, organic/g-C3N4 hybrids and synergistic combinations of g-C3N4 and traditional flame retardants, have been developed, and their fire behaviors in various polymer matrices have been investigated. In this chapter, we summarize the utilization of 2D g-C3N4 in improving the flame retardancy of polymeric materials, and present the preparation and surface modification approaches of 2D g-C3N4, as well as the approach to the fabrication of g-C3N4/polymer nanocomposites. Special emphasis is placed on recent advances in g-C3N4 for reducing the fire hazards of polymeric materials. Finally, the current challenges and future perspectives of g-C3N4-based flame-retardant polymer nanocomposites are proposed for achieving practical applications in fire safety fields.
