Fabrication and origin of new flame retarding bismaleimide resin system with low dielectric constant and loss based on microencapsulated hexaphenoxycyclotriphosphazene in low phosphorus content

摘要: Abstract To maintain sustainable development, developing new and effective phosphorus flame retardants that can simultaneously endow thermally resistant thermosetting resins with outstanding retardancy dielectric properties is a great but worthy challenge. A retardant coded as MH, polyamide microencapsulated hexaphenoxycyclotriphosphazene (HPCTP), was synthesized through interfacial polymerization. The influences of main synthesis parameters on the morphology thermal stability were discussed. Furthermore, kind modified bismaleimide (MH/BD) prepared by incorporating MH into 4, 4' – bismaleimidodiphenylmethane/o, o’-diallylbisphenol (BD) resin, structure performances MH/BD studied compared those HPCTP/BD resins. Results show which content small only 0.33 wt%, has retardancy, mainly reflected high limiting oxygen index (LOI), low total heat evolved smoke production; while in should be higher than 1.30 wt% to get similar retardancy. Moreover, when contents HPCTP are same, exhibit lower constant loss over wide frequency from 102 104 Hz resins, suggesting former more attractive used applications related electric electronic fields. mechanisms behind these intensively interaction between core shell effect crosslinked cured responsible for properties. research reported herein provides method origin prepare performance