A phosphaphenanthrene‐based derivative for simultaneously improving flame retardant and smoke suppression of epoxy resin composites

Abstract

Epoxy resin (EP) have the disadvantage of high flammability and large amount of smoke, which greatly restricts its wide application in basic material. In order to obtain EP with excellent smoke inhibition and flame retardance, the flame retardant called as PBO, which with both condensed phase and gas phase flame‐retardant effects, was synthesized by the reaction among p‐phenylenediamine, DOPO, and indole‐3‐carboxaldehyde. From combustion results, EP containing PBO obtained V‐0 grade with a significantly improvement from 22.5% to 30.2% in limiting oxygen index. In comparison with EP, total smoke production, total heat release and the peak of heat release of EP/PBO‐1.0 were declined by 32%, 41.5%, and 37.4%, respectively. Besides, Tg of EP composites also had a certain degree of improvement, which due to the increase of rigidity and crosslinking density of EP caused by the addition of PBO. Meanwhile, the analysis of chars and pyrolysis products of PBO presented that the improvement was assigned to two phase synergy through barrier effect of chars in condensed phase and interrupt chain reaction in gaseous phase.

Molecules Featuring the Azaheterocycle Moiety toward the Application of Flame-Retardant Polymers

“…To broaden the scope of applications for flame retardants derived from fused ring azaheterocycles in polymer materials, researchers have explored various compounds such as porphyrins and their derivatives, carbazoles and their derivatives, − quinolines and their derivatives, − indoles and their derivatives, etc. Yang et al synthesized two multifunctional additives, 5,10,15,20-tetrakis­(4-bromophenyl)­porphyrin (TBPP) and zinc 5,10,15,20-tetrakis­(4-bromophenyl)­porphyrin (Zn-TBPP), for high-performance polystyrene (PS) composites.…”

Molecular design and properties of intrinsic flame‐retardant P‐N synergistic epoxy resin

“…Epoxy resin (EP) is a crucial thermosetting polymer that finds extensive applications across diverse domains. 1 However, the flammability of EP limits its potential applications in structural materials for electronic devices, aircraft, and ground vehicles. To address this issue, a new organic flame retardant containing phosphorus and nitrogen was developed by studying the flame retardant properties of polymers and related mechanisms.…”

“…Epoxy resin (EP) is a crucial thermosetting polymer that finds extensive applications across diverse domains 1 . However, the flammability of EP limits its potential applications in structural materials for electronic devices, aircraft, and ground vehicles.…”