Halogen-free flame retardation and silane crosslinking of polyethylenes

Halogen-free flame-retarded and silane crosslinkable polyethylenes have been prepared by a melt process using magnesium hydroxide (MH) as a flame retardant. The effects of silane concentration, peroxide concentration, etc. on the silane grafting on linear low density polyethylenes were investigated. The thermal analysis of the silane crosslinked polyethylenes was performed by thermogravimetry (TG), and its results show that silane crosslinking provides an increase in the thermal stability of polyethylenes. The combustion characteristics of the silane crosslinked polyethylenes containing MH have also been studied using limiting oxygen index (LOI) and the Cone Calorimeter. The rate of heat release and smoke emission of the silane crosslinked polyethylenes decrease, and LOI, the time to ignition and the residue after combustion increase as MH content increases.

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