Abstract
Recently a heat barrier composite fabric structure has been developed [UK Pat 2279084 B, 20 June 1995] which can withstand air exposure temperatures up to 1200 degrees C. This novel assembly is a multilayer fabric which comprises a flexible nonwoven core of flame-retardant fibres throughout which an intumescent is dispersed, This paper reviews the various stages of development of this novel composite textile structure since 1992, where a number of flame-retardant cellulosic fibres have been combined with selected intumescents in suitable composite structures. High flame and heat resistance and very low heat release properties are features of these composite structures. It has been demonstrated that on heating such systems, both components char by chemically and physically compatible mechanisms, resulting in a chemical interaction to form a fibrous char-reinforced intumescent char or 'char-bonded' structure which is unusually resistant to oxidation.