Self‐Assembling Macromolecular Flame Retardant Polyvinyl Alcohol Films With Phytic Acid and Melamine

ABSTRACT To meet the growing demand for environmentally friendly and multifunctional flame retardant materials, this study developed a high‐performance composite film by introducing bio‐based flame retardants into a polyvinyl alcohol (PVA) matrix. The film was fabricated via supramolecular self‐assembly of phytic acid (PA) and melamine (MEL), offering an effective and green alternative to conventional flame retardants, which often suffer from toxicity, incompatibility, and compromised mechanical properties. Characterization techniques including FTIR, SEM, TGA, LOI, and UL94 were used to investigate the flame retardant mechanism. Results showed that the synergistic action of PA and MEL enabled the film to reach a LOI of 31% and a UL94 VTM‐0 rating with only 10% additive content. PA facilitated char formation through phosphoric acid release, while MEL released ammonia to dilute combustible gases, jointly forming a dense, protective carbon layer that inhibits flame propagation. In addition to excellent flame resistance, the film maintained high transparency, good mechanical strength, and strong UV shielding, demonstrating potential for sustainable flame‐retardant applications.