Investigations of thermal degradation and electrical properties of polyamide materials versus polybismaleimide materials for fire-fighters helmets

In this paper, a study on thermal degradation of polybismaleimide materials for fire-fighters helmets compared to polyamide materials from comercial fire-fighters helmet was performed by applying simultaneous mass spectrometry and Fourier transform infrared spectroscopy of gas products from a thermogravimetric analyzer. The results of TG measurement indicate a difference in the mass loss behavior between the two polymers materials. The thermal decomposition of polyamide material takes place in the single stage in the temperature range of 400-460°C with a mass loss of 98% while that of polybismaleimide material takes place in two steps with a residuu at 650°C of 85%. The electrical analyzes consisted in the application of the electric breakdown test and the calculation of the breakdown parameters. Following the experiments, it has been found that the voltage breakdown has approximately 4 times higher values for polybismaleimide material than compared to polyamide materials.