Improved electrical heating properties for polymer nanocomposites by electron beam irradiation

Nowadays, light weight heating materials are attractive and conductive polymer nanocomposites (CPC) were potential applications in being used as Joule heating materials. To prepare CPCs with high efficiency and stable heating, nanocomposites of high density polyethylene (HDPE) and carbon nanotubes (CNTs) were treated by electron beam (EB) irradiation. The influence of EB irradiation on the composites was characterized by DSC, TGA, TMA, SEM, and DMA. The results showed that gel content and thermal decomposition temperature increased and the thermal expansion coefficient decreased with increasing the irradiation dose. Meanwhile, electrical and thermal conductivity of irradiated samples also increased. These were attributed to crosslinking of HDPE by EB irradiation. As a result, surface temperature (Ts) of samples after irradiation was heightened and the correspondence heat efficiency was improved. Mechanical properties of the composites were significantly improved after irradiation, especially at the temperatures which were higher than melting point of HDPE, indicating the improvement of thermal stability by irradiation crosslinking. It made the irradiated HDPE/CNTs composites good candidates for application in the electrical heating.