Corrugated cardboard is widely used in Japan in shelters and medical facilities for earthquake response, because of low price, strength and recyclability. Fire retardancy is considered important for safety.
Six flame retardants (FRs) were tested including ammonium sulphate, TOP, TBP and three commercial FRs from Marubishi Oil Chemical Co. Ammonium sulphate gave the best fire performance (lowest peak heat release rate PHRR) but was considered potentially toxic at the application levels needed. A commercial nitrogen-phosphorus (N-P) FR gave significantly reduced PHRR at <20% loading, better than the halogenated FR tested. The authors conclude that P and N are both required for corrugated cardboard flame retardancy and that halogen is not needed.
“The Flame retardancy study of the furniture made from corrugated cardboard”, Mochizuki et al., Energy Procedia 89 ( 2016 ) 93 – 97 http://dx.doi.org/10.1016/j.egypro.2016.05.013