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Thermal and Combustion Behaviors of Rigid Polyurethane Foams Prepared with Heteroaromatic Polyol

Rigid polyurethane foams (RPUFs) were prepared using heteroaromatic polyether polyol, sucrose polyether polyol, and aromatic polyester polyol as the matrix polyol; traditional phosphorus flame retardant dimethyl methyl phosphonate (DMMP) was added to improve its flame retardancy. The thermostability and the combustion performance of RPUFs were studied using dynamic mechanical analysis (DMA), thermogravimetric analysis (TG), and the cone calorimeter test. The results showed that the glass transition temperature (Tg) of RPUFs using heteroaromatic polyether polyol as the matrix polyol was higher than that of RPUFs prepared with sucrose polyether polyoland aromatic polyester polyol. The thermogravimetric analysis (TGA) test revealed that the first degradation of RPUFs with heteroaromatic polyether polyol occurred at 290°C, and it was higher than the RPUFs with aromatic polyol and sucrose polyol, respectively. This demonstrated that the special heteroaromatic polyol exhibited better thermal stability. The cone calorimeter test showed that the peak heat-release rate (P-HRR) and THR of the RPUFs with heteroaromatic polyol were higher than those of RPUFs with the sucrose polyol and aromatic polyol. The total smoke release (TSR) value of the RPUF with aromatic polyol was approximately 302 m^2/m^2, which was significantly lower than those of RPUFs with heteroaromatic polyol (342 m^2/m^2) and sucrose polyether polyol (371 m^2/m^2).