Flammability of blends of low‐density polyethylene and ethylene vinyl acetate crosslinked by both dicumyl peroxide and ionizing radiation for wire and cable applications

Abstract

Formulations of chemically crosslinked and radiation-crosslinked low-density polyethylene (LDPE) containing an intumescent flame retardant such as ammonium polyphosphate were prepared. The influence of blending LDPE with poly(ethylene vinyl acetate) (EVA) as well as the effects of a coadditive such as talc on flammability was investigated. Chemical crosslinking by dicumyl peroxide and crosslinking by ionizing radiation from an electron-beam accelerator were both used and compared. An increase in the limiting oxygen index (LOI) was found by the partial replacement of LDPE with EVA. The effect of talc on the flammability depended on the amount of talc in the formulations. The addition of a small amount of talc increased LOI and reduced smoke during cone calorimeter measurements. A higher amount of talc led to a decrease in the LOI values. Formulations crosslinked by ionizing radiation yielded lower LOI values than chemically crosslinked formulations. This could be attributed to the use of trimethylolpropane triacrylate as a crosslinking coagent in formulations crosslinked by ionizing radiation.

Effects of ageing on the fire behaviour of flame-retarded polymers: a review

“…Change in flame retardancy may be primarily attributed to modification of the polymer. Crosslinking can prevent the expansion of a material containing an intumescent system . Chain scission can lead to small molecules with resulting decrease in thermal stability.…”

Thermal and flammability properties influenced by Zn/Al, Co/Al, and Ni/Al layered double hydroxide in low‐density polyethylene nanocomposites

“…The extensive applications of low‐density polyethylene (LDPE) are mainly due to their varied mechanical properties, resistance to chemical attacks, easy processability, and excellent electrical properties . However, low melting temperature, low thermal stability, high flammability, and incompatibility with most hydrophilic additives are some disadvantages.…”

“…The extensive applications of low-density polyethylene (LDPE) are mainly due to their varied mechanical properties, resistance to chemical attacks, easy processability, and excellent electrical properties. 1 However, low melting temperature, low thermal stability, high flammability, and incompatibility with most hydrophilic additives are some disadvantages. The thermal properties and flame retardancy of polyolefins can be improved by adding small amounts of inorganic particles [e.g., Mg(OH) 2 ], which are mechanically mixed with the polymer.…”

Flame-retardant properties of ethylene-vinyl acetate/oil sludge/ fumed silica composites

“…It is noted that EOS1 and EOS4 both produced more smokes in the first 250 s than the EVA. The smoke density can be effectively reduced [34]. EOS4 produced less smoke than EOS1 because of the addition of SiO 2 , rendering easier way to form the char layer.…”