Smoke suppression and thermal conductivity of epoxy resin modified byAl₂O₃and hyperbranched flame retardant

Abstract

In this work, aluminum oxide (Al 2 O 3 ) was added to hyperbranched flame retardant (PTDOB) modified epoxy resin (EP) system to develop a novel EP thermoset (Al 2 O 3 -PTDOB/EP) with superior comprehensive performance.Al 2 O 3 -PTDOB/EP exhibited excellent flame retardancy, smoke-suppressing effects, and enhanced mechanical properties due to the crack pinning effects caused by the introduction of Al 2 O 3 . In detail, the limiting oxygen index (LOI) and UL-94 rating of Al 2 O 3 -PTDOB/EP-3 reached 34.6% and V-0 rating, respectively. Cone calorimeter test showed that the total heat release, total smoke production (TSP) and average effective heat of combustion of Al 2 O 3 -PTDOB/ EP-3 were reduced by 14.5, 27.3 and 19.2% in comparison to PTDOB/EP, respectively. Furthermore, the impact, tensile and flexural strengths of Al 2 O 3 -PTDOB/EP-3 were significantly improved by 16.7 28.4 and 10.7%, respectively, because the addition of Al 2 O 3 provided the carbon layer barrier and crack pinning effect for the EP matrix. Moreover, thermal conductivity of Al 2 O 3 -PTDOB/EP was also improved due to the excellent thermal conductivity of Al 2 O 3 , which had broadened its application in the field of electronic packaging.

Al2O3/h‐BN/epoxy based electronic packaging material with high thermal conductivity and flame retardancy

“…Increased power density of electronic devices makes thermal runaway more frequent, thus requires for higher flame retardant performance of EP 61 . Due to the physical barrier effect of Al 2 O 3 spheres and h‐BN sheets, as well as functionalized amino groups on the surface of Al 2 O 3 spheres and h‐BN sheets, the PDA‐BNAO/EP is expected to exhibit excellent flame retardancy 14,22 . The flame retardancy of pure EP and PDA‐BNAO/EP were investigated by a micro calorimeter, Figure 5.…”

“…[14][15][16][17] Therefore, it is highly desirable to develop electronic packaging materials with excellent high thermal conductivity and flame retardancy. 15,18,19 Inorganic additives, such as boron nitride (BN), 14,15,20,21 alumina (Al 2 O 3 ), 16,22 as well as carbon materials (e.g., carbon nanotubes (CNTs), 23 graphene 24,25 and expandable graphite (EG) 26 ) are employed to realize the compatibility of high thermal conductivity and flame retardancy of EP, in which, carbon materials are electrically conducting, which limits their applications in electronic packaging field. 27 Al 2 O 3 is favored by electronic packaging industry to improve the thermal conductivity of EP, [28][29][30] because of its low price.…”

Thermally conductive polymer-based composites: fundamentals, progress and flame retardancy/anti-electromagnetic interference design

“…Recently, researchers are working to develop flame-retardant polymers and polymer-based composites to enhance their flame retardancy, so as to reduce the risk of fire and mitigate the impact of related adverse consequences. 156–162…”

A new‐type terephthalonitrile derivative flame retardant of bi‐DOPO compound with hydroxyl and amino groups on epoxy resin

“…Epoxy resin (EP) has excellent mechanical and chemical properties and has been widespread used in coatings, adhesives, architectural decoration, and other fields. 1,2 However, the main constituent elements of EP are C and H, which lead to the flammability of EP and the release of a large amount of heat during combustion. They significantly limit the further application of EP and make it easy to break out of the fire.…”