A PIN FR package in epoxy shows aviation fire performance and reduced smoke emission and toxicity. DGEBA-based epoxy was combined with FRs, then applied to woven glass fibres (GF) to 0.6 mm thickness. A PIN flame retardant package (resin micro-encapsulated red phosphorus + zinc borate + aluminium tri hydroxide) was assessed, testing addition of each component separately in the GF-resin, and with combinations up to 52% total FR loading. At total loading of the PIN FR package around 30%, peak heat release rate (PHRR) was reduced by over 50% and also delayed in time (compared to neat GF-epoxy). Self-extinguishing was achieved in the vertical burn test and burn length reduced by around two thirds. Smoke density was increased by the PIN FR package compared to neat GF-epoxy, but could be reduced by adding zinc borate or aluminium trihydroxide only. Smoke toxicity (Microtox cytotoxicity test) was lower with the PIN FR package than for neat GF-epoxy.
“Cleaner production of flame-retardant-glass reinforced epoxy resin composite for aviation and reducing smoke toxicity”, F. Özmen et al., J. Cleaner Production 276 (2020) 124065 https://doi.org/10.1016/j.jclepro.2020.124065