A novel intumescent flame-retardant polyethylene system

A novel carbonization agent was synthesized and characterized. The flame retardancy and thermal behavior of a new IFR system with and without metal chelates for LDPE were investigated by LOI, UL-94 test, and TGA. Metal chelates can remarkably improve the flame retardant performance of intumescent systems according to the tested results of LOI values and UL-94 ratings because they can act both as inhibitors of radicals and as promoters of carbonization. The TG curves show that the amounts of residue of IFR-PE/metal chelate systems increase compared to those of PE and IFR-PE at temperatures ranging from 400 to 650 degrees C. The IFR-PE/metal chelate system can obviously reduce the amounts of decomposing products at higher temperatures and promotes the formation of carbonaceous charred layers. A LOI value of 29.8 and UL-94 V-0 rating could be achieved when the synthesized carbonization agent, APP, MP, and CoOSA were added into LDPE.