Flame‐retardant epoxy resin compounds containing novolac derivatives with aromatic compounds

Abstract

New flame‐retardant epoxy resin compounds containing novolac derivatives with specific aromatic compounds have been developed. After crosslinking reactions between epoxy resin and hardener, the epoxy resin compounds formed highly flame‐retardant network structures that were obtained by including biphenylene and phenylene moieties in the main chains of novolac‐type epoxy resin and phenol novolac resin hardener. The high flame retardancy is due mainly to the stable foam layers that form during combustion because of the low elasticity at high temperatures and the high pyrolysis resistance of the compounds. Furthermore, the addition of excess phenol derivative hardener not only facilitates the formation of the foam layers by decreasing the crosslink densities but also reduces the amount of flammable substances generated from the epoxy resin compounds during combustion. The use of a multifunctional epoxy resin containing four glycidyloxy groups in the compounds improved characteristics such as heat resistance and strength at high temperatures, while maintaining excellent flame retardancy. Copyright © 2001 John Wiley & Sons, Ltd.

Thermal decomposition, combustion and flame‐retardancy of epoxy resins—a review of the recent literature

“…For example, Dyakonov et al 4 showed that the thermal stability increases with increasing crosslink density for the analogous resins. On the other hand, Iji and Kiuchi5 found that the ‘pyrolysis resistance’ of novolac epoxy resins was slightly decreased by the addition of an excess of hardener. In general, the thermal stabilities of aromatic epoxy resins are higher than those of aliphatic ones, even though the crosslink densities of the aromatic networks may be lower.…”

Curing behavior and thermal properties of trifunctional epoxy resin cured by 4, 4’-diaminodiphenyl sulfone

“…However, the conventional epoxy resins are inefficient to satisfy the required properties of advanced materials, such as, high thermal resistance [8][9][10]. It is known that several ways can be taken to enhance the thermal property of epoxy compound.…”

Properties of epoxy resin composites containing 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide

“…However, its inherent flammability limits its specific applications. Thus, improving the flame retardancy of epoxy resin can lead to its more widespread applications.Some scholars have done some research on the flame retardancy of epoxy resin [4][5][6][7][8] Concerning the flame retardancy of epoxy resin, halogenated compounds meet flame-retardant requirements. However, halogen-containing compounds produce corrosive and poisonous smoke during burning, thereby harming human health and posing risks to environment safety.…”