The anti-dripping intumescent flame retardant finishing for nylon-6,6 fabric

Nylon-6,6 fabric has been widely used in military and civilian area for many years. However, the melting drip problem has not been effectively solved despite the efforts made in the last two decades. An intumescent flame retardant system, containing ammonium polyphosphate, melamine and pentaerythritol, has been proved to be effective on preventing melting drip during burning of nylon-6,6 fabric in this study. The LOI and the vertical flammability test indicate that this IFR (intumescent flame retardant) system could improve the flame retardancy and impart dripping resistance to nylon-6,6 fabric. Thermal behaviour of nylon-6,6 fabric treated with IFR system was investigated by thermogravimetric (TG) and differential scanning calorimetric(DSC) experiments. The results indicate that char residue of treated samples are above 13%, and the highest value could reach up to 24% at 750 °C which is much higher than that of the untreated fabric. SEM graphs of residue of treated and untreated nylon-6,6 fabric show that IFR could promote formation of residual char which impart anti-dripping property to nylon-6,6 fabric. The tensile property test shows that tensile strength of treated fabric decreased.