Epoxy-based fire protection coating: innovative APP and Cu₂O formulation
A cutting-edge intumescent fire protective coating for steel demonstrates remarkable results in reducing heat and fire hazards. By optimizing the ratio of ammonium polyphosphate (APP) and copper (I) oxide (Cu₂O), fire safety parameters improved significantly.
A research team has developed a self-intumescent fire protective coating by combining epoxy resin (EP) with ammonium polyphosphate (APP) and copper (I) oxide (Cu₂O). Lab-scale big panel tests evaluated the performance of various mass ratios of APP to Cu₂O on steel plates.
The optimal formulation (APP/Cu₂O ratio 6:4) achieved a backside temperature of just 234.5 °C — far below the critical steel failure temperature of 500 °C. In contrast, unprotected steel plates reached temperatures up to 529 °C.
Reading tip: Epoxy resins
Due to their outstanding properties, epoxy resins are more widely used in the coating industry than almost any other class of binder. In their new reference book “Epoxy Resins“, the authors Dornbusch, Christ and Rasing explain the basics of the chemistry of the epoxy group and use specific formulations to explain the use of epoxy and phenoxy resins in industrial coatings – including corrosion protection, floor coatings, powder coatings and internal can coatings.
Enhanced safety with a lower fire risks
Beyond heat protection, the coating significantly reduced key fire hazard parameters. Compared to pure epoxy resin, peak heat release rates dropped by 80%, smoke production by 59.5%, and CO production by 75%. These improvements are attributed to the formation of an intumescent char layer that insulates against heat. This innovation represents a promising step forward in fire safety technology for industrial and structural applications.
Source: Journal of Coatings Technology and Research, Volume 21, Pages 547–558, 2024
