Thermal Decomposition Behavior of Cotton/Polyester Blended Yarn Fabrics Treated with Flame Retardants.

Abstract

The thermal decomposition behavior in air of flame-retardant cotton/polyester (C/P) blended yarn fabrics was investigated by thermogravimetry-differential thermal analysis/mass spectrometry. Pyrovatex CP New and tetrabromobisphenol A (TBP-A) were used as flame retardants. When the fabric was treated with Pyrovatex CP New, the evolved gases in thermal decomposition, such as water, methanol and carbon dioxide, were analyzed from the mass profile data at m/z 18, 31 and 44. These results suggested that phosphonopropionic acid, which was liberated from N-methylol 3-(dimethyl phosphono) propionamide, the main component of Pyrovatex CP New, promotes the dehydration and carbonization of cotton cellulose. On the other hand, the TG curve of treated fabric with TBP-A showed that TBP-A promotes the thermal decomposition of fabric. The evolution behavior of water and carbon dioxide obtained from the mass profile data at m/z 18 and 44 suggested that the acceleration of thermal decomposition occurs in cotton. When the fabric was treated with Pyrovatex CP New and TBP-A by two-component sequential treatment, TBP-A did not promote the thermal decomposition of fabric and was released in the gas phase above 300°C. From this result, it is thought that Pyrovatex CP New treatment inhibits the acceleration of thermal decomposition. It is concluded that Pyrovatex CP New and TBP-A give a flame retardancy to C/P blended yarn fabric in the condensed phase and the gas phase, respectively.