Thermal decomposition of bisphenol A-based polyetherurethanes blown with pentane: Part II—Influence of the novel NaH2PO4/NaHSO4 flame retardant system

The thermal degradation process of ethoxylated bisphenol A (BPA) and oxyalkylenated 2,6-toluylenediamine-based polyurethane (PU) foams blown with pentane and flame retarded by novel NaH2PO4 and NaHSO4 intumescent system (5:3, w/w) was studied by thermogravimetry coupled with mass spectrometry (TG–MS), thermogravimetry coupled with Fourier transform infrared spectroscopy (TG–FTIR), pyrolysis–gas chromatography coupled with mass spectrometry (Py/GC–MS) and diffuse reflectance Fourier transform spectroscopy (DRIFTS) methods. It has been found that NaH2PO4/NaHSO4 system is active both at the initiation stage of PU decomposition as well as it catalyses cross-linking reactions that lead to enhanced char formation during degradation; both effects contribute to the overall flame retardation effect.