Posted on 07/03/2022 in Fire Safety 2022
Reactive PIN FR for polyurethane foam

A reactive phosphorus – nitrogen PIN FR improved both fire performance and mechanical properties in flexible PUR foam. A complex dihydroxy P – N molecule 2- (( bis (2-hydroxyethyl) amino) methyl) -5,5-dimethyl -1,3,2-dioxaphosphinane 2-oxide (HAMPP) was synthetised in three reaction stages and tested in flexible polyurethane foam at 0 – 10% loading. The dihydoxy structure means the molecule can react into PUR or polymerise. Tests showed that at 10% loading, HAMPP-PUR showed LOI (Limiting Oxygen Index) increased from 19 to nearly 24, peak heat release rate decreased by around 25% and UL 94 V-0 pass. The foam mechanical properties were improved, in particular tensile strength and elongation at break. The reactive PIN FR showed to function both by generating a molten viscous protective char layer on the foam surface and by releasing water and nitrogen gases.

Flame Retardancy Behaviors of Flexible Polyurethane Foam Based on Reactive Dihydroxy P−N-containing Flame Retardants”, Y. Ding et al., ACS Omega 2021, 6, 16410−16418

Share This