Abstract:

In this study， flame⁃retardant reinforced PBT compounds were prepared through a multi⁃component combination of halogen flame retardants with phosphorus， nitrogen， and phosphorus⁃nitrogen⁃based flame retardants， and their glow⁃wire ignition temperature （GWIT） was investigated. Brominated polystyrene， antimony trioxide， diethylaluminum hypophosphate， melamine cyanurate， melamine polyphosphate， and carbon⁃based composite halogen⁃free flame retardant were used as flame retardants to compound with the reinforced PBT for flame⁃retardant experiments. The enhanced PBT compound only with halogen flame retardant or with halogen⁃free flame⁃retardant system cannot meet the requirements of IEC60335⁃1 for the GWIT of current carrying components in unmanned electrical appliances. By a combination of different types of flame retardants and the use of bromine⁃nitrogen⁃phosphorus synergistic flame retardant， the enhanced PBT could ultimately achieve the best flame⁃retardant performance and simultaneously meet the requirements of flame⁃retardant standard at GWIT>825 ℃， GWFI>960 ℃， and UL 94 V⁃0.

Key words: polybutylene terephthalate, flame retardant, high glow-wire ignition temperature, ignition temperature, reinforcement