Fire safe epoxy composite with low dielectric properties from a combination of fluoro-phosphonium salt, melamine and copper hydroxystannate

A phosphorus-fluorine containing compound tetraphenylphosphine hexafluorophosphate (Ph4PPF6) was synthesized by one-step method and characterized FTIR, NMR, SEM, EDX. Epoxy resin (EP) cured with an aliphatic hardener Ph4PPF6 as a multifunctional additive were fabricated. The combined effects of melamine (MEL) copper hydroxystannate (CuHS) on the fire safety, thermal stability, smoke toxicity dielectric performances EP investigated. It is found that 2 wt% P (from Ph4PPF6) 10 MEL (sample 2P 10M) from 5 MEL, CuHS 5M5C) pass V0 classification in UL-94 VB tests. cone calorimetric tests these composites reveal peak heat release rate sample 5M5C reduced 64.2% comparison to pure EP. toxic gases including HF, CO, HCN are different extent when used co-additives. loss 10M 26.3%