Flammability Properties of -irradiated Intumescent Flame-retardant HDPE/EVA Composites
The influence of -irradiation on high density polyethylene/ ethylene—vinyl acetate copolymer composites consisting of ammonium polyphosphate and nylon 6 as intumescent flame-retardant additives is investigated. Cone calorimetry, thermogravimetric analysis, and Fourier transform infrared have been performed to characterize their flammability and thermal properties. The irradiated samples show slight reduction in peak heat release rate at suitable irradiation dose levels but exhibit less efficiency in fire protection in comparison with the non-irradiated sample. Thermogravimetric analysis results indicate that the irradiated samples have a higher thermal-oxidative stability than that of the non-irradiated sample. The intermolecular cross-links of the composites induced by -rays are suggested to be responsible for these behaviors.