Influence of halloysite nanotubes onto the fire properties of polymer based composites: A review

Abstract : Fire retardancy is of crucial importance for most of the polymer applications and fire proofing materials are often based on polymer blends with high fire retardants contents (up to 60wt%) which induce cost increase and lower mechanical performances. The use of ammonium polyphosphate (APP) as fire retardant allows maintaining good mechanical properties but it can be removed from the polymer matrix under hygrothermal conditions. In this context, halloysite nanotubes (HNTs) offer a good alternative as carriers of flame retardant systems to control the migration of the flame retardant molecules encapsulated in the HNT lumen for long-term aging properties. This review highlights the influence of the presence of HNTs and its derivatives on the fire retardancy performances of polymer-based composites. The discussion is examined according to the nature of the polymer from thermoplastics to thermosets.