Design of Experiments-Based Fire Performance Optimization of Epoxy and Carbon-Fiber-Reinforced Epoxy Polymer Composites

The fire performance of epoxy and carbon-fiber-reinforced polymer (CFRP) composites with and without fire retardants (FR) (i.e., ammonium polyphosphate (APP), aluminum trihydroxide (ATH), melamine (MEL), expandable graphite (EG)) was investigated. A design of experiment (DoE) approach was applied to study the single- and multifactorial effects of FR. The fire performance of epoxy and CFRP was evaluated by limiting the oxygen index (LOI) and heat release, which were obtained by limiting the oxygen index test and cone calorimetry. It was found that mixtures of 70 wt.-% epoxy, 24.6 wt.-% of APP, and 5.4 wt.-% MEL resulted in the highest LOI level of 45 within tested groups for epoxy resin and also for CFRP specimens (LOI level of 39). This mixture also resulted in the lowest average heat release rate (HRR180s) of 104 kW center dot m-2 and a spec. total heat release (THR600s) of 1.14 MJ center dot m-2 center dot g-1, indicating the importance of balancing spumific and charring agents in intumescent systems and synergy thereof.

Automated summary

This study investigates the fire performance of epoxy and carbon-fiber-reinforced polymer composites with and without fire retardants. The effects of different fire retardants on the oxygen index and heat release of the composites were studied. The results show that the mixture of 70 wt.-% epoxy, 24.6 wt.-% APP, and 5.4 wt.-% MEL has the highest oxygen index and the lowest heat release rate.