Modification of Epoxy Resin with a Phosphorus, Nitrogen, and Fluorine Containing Polymer to Improve the Flame Retardant and Hydrophobic Properties

Abstract Targeting high‐effective modification of flame retardant epoxy resin, elements including phosphorus, nitrogen, and fluorine are simultaneously incorporated into a polymer named as PFNP. A certain amount of amino groups are preserved on PFNP chains to participate in the curing of epoxy resin. The reactive groups and segments contain 9,10‐dihydro‐oxa‐10‐phosphaphenanthrene‐10‐oxide (DOPO) endowed PFNP with good compatibility in epoxy resin. The proper addition of PFNP improves the mechanical property and T g values of epoxy resins. The limiting oxygen index values of EP/PFNP increases while the peak heat release rate, heat release capacity, and total heat release values reduce after introduction of PFNP. Samples with contents of PFNP higher than 5 wt% reach UL‐94 V‐0 rating without dripping. Notably, the migration effect of trifluoromethyl (CF 3 ) groups not only increases the water contact angles, but also reduces the dielectric constants of epoxy resins.