Brominated Epoxy Resin BE-20

BE-20 achieves flame retardancy through the radical-trapping mechanism: during combustion, HBr released from the brominated aromatic backbone interrupts the chain-branching reactions of the flame. Bromine content of 18–22% achieves UL94 V-0 rating when combined with antimony trioxide (1:3 Br:Sb synergistic system). BE-20 is used in printed circuit board laminate systems (FR-4 equivalents), wire and cable coating insulations, and intumescent-free fire-retardant architectural coatings where halogenated additives are accepted. Note: not suitable for RoHS-restricted applications.