Thermal stability of flexible polyurethane foams containing modified layered double hydroxides and zinc borate
Xu Zhang, Sen Li, Zhi Wang, Gaohui Sun, Po Hu
Abstract
Flexible polyurethane foams (FPUFs) have been modified to contain layered double hydroxides (LDHs) by dihydrogen phosphate (H2PO4−). The thermal stability of the prepared foams has been characterized using thermogravimetric analysis (TGA) at 5, 10, 20, 30, and 40 °C/min heating rates. The experimental data indicate that the temperature range for the two pyrolysis stages of FPUF is about 212–350 °C and 350–565 °C, respectively. Integral programmed decomposition temperature (IPDT) has been calculated according to the measured data, which was found that the IPDT of the modified FPUF was increased to 526 °C. Additionally, the thermal stability of FPUF composite has been also evaluated by the activation energy (E) on the basis of the pyrolysis kinetics of FPUF composites during thermal decomposition using Coats–Redfern integral method. These results manifest that the presence of intercalated LDHs enhances the thermal stability of FPUF.