Applications of irradiation to polyethylene for flame retarded wire and cable insulation

The properties of polyethylene materials exhibit good insulation and radiation resistance, but exhibit poor flame resistance. Flame retardant properties of the polyethylene were improved by the radiation induced grafting or crosslinking. When the various flame retardants were fixed onto polyethylene, the amount of fixation in grafting was increased with the increase of radiation dosages. In the case of grafting, it is necessary for high grafting yield that the polyethylene films were swelled before irradiation with γ-rays or electron beams. It is a suitable method for the fixation of flame retardant that polyethylene samples were blended with various flame retardants at 1250C and then blended polymers were crosslinked by the electron beams at room temperature. (author)