In this Feature Article, we discuss recent developments of flame retardant polymers. Three approaches are considered: (i) inherently flame retardant polymers, (ii) chemically modified polymers and (iii) flame retardants as additives for polymers. We have tried to show the new directions and concepts emerging in the field of flame retardancy. We have mainly focused our comments on flame retardants, nanofillers and surface treatment because very promising concepts appeared recently in the published literature. Synergistic aspects are also fully discussed.

Lignin-derived flame retardants represent one of the most promising directions for next-generation flame retardants due to their sustainability, environmental benefits and comparable efficiency to current non-bio-based counterparts.