Flame retardants: intumescent systems

Abstract

Intumescent fire retardant additives undergo a thermal degradation process on heating, which produces a thermally stable, foamed, multicellular residue called ‘intumescent char’. When these substances are added to a polymeric material which is later involved in a fire, they produce an intumescent char which accumulates on the surface, while the polymer is consumed, providing insulation to the underlying materials and partially protecting it from the action of the flame.