Flame-retardant innovations in bio-based treatments for lignocellulosic natural fibers: A review.

The growing environmental concerns tied to synthetic materials have sparked interest in renewable, biodegradable, and sustainable alternatives like lignocellulosic fibers (LFs) from plants and agricultural waste. While advantageous, the inherent flammability of LFs limits their use in safety-critical applications, necessitating effective flame-retardant treatments. Traditional flame retardants (FRs) involve harmful chemicals, which pose environmental and health risks. Consequently, research is increasingly focusing on bio-based FRs derived from natural compounds such as polysaccharides, proteins, and phytic acid. These materials have shown promise in enhancing the fire resistance of natural fiber through mechanisms that improve thermal stability and char formation. This review provides a comprehensive analysis of recent advancements in bio-based flame retardant solutions alongside the physical, mechanical, thermal, and flammability properties of LFs. It also examines recent techniques for applying bio-based coatings to fibers and explores the latest fiber applications. By evaluating the interactions between these FRs and fiber structures, the review highlights the potential for developing effective, sustainable solutions that can facilitate the safe and environmentally friendly use of LFs across various applications. Ultimately, this review aims to contribute to a transformative shift toward safer and more sustainable materials in the face of growing environmental challenges.