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

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 (CF3) groups not only increases the water contact angles, but also reduces the dielectric constants of epoxy resins.