High-resolution thermogravimetry/coupled mass spectrometry analysis of flame-retardant rubber

A bromobutyl rubber composition containing a variety of conventional flame retardants, such as Saytex (decabromodiphenyl oxide), Sb2O3, chlorinated paraffin wax, and polychloroprene rubber, was prepared and used to coat nylon 6 fabric in a laboratory-coating device. An attempt was made to evaluate the decomposition profile, the evolved gases, and the kinetics of the decomposition process at a dynamic heating rate with high-resolution thermogravimetric analysis (HR-TGA). HR-TGA was used with mass spectrometry for evolved gas analysis (EGA). The HR-TGA results were compared with results from conventional thermogravimetric analysis (TGA) at a constant heating rate; the former offered sharp transitions, an economic timescale, and an accurate activation energy. The resolution optimization for stability analysis and the effect of its variation on the kinetic parameters offered better results for HR-TGA than conventional TGA. A lifetime and temperature relationship was evaluated in HR-TGA with Toop's method, and it was observed that the shelf life decreased sharply with temperature. The effluents HBr, HCl, Br ., and Cl ., generated between 210 and 496degreesC during EGA, were correlated with the thermal stability and fire-retardancy behavior of the material. (C) 2003 Wiley Periodicals, Inc.