TraNa – Colorable and Flame-Resistant Sheet Molding Compo

In the aviation sector, ecologically beneficial material solutions are becoming increasingly important with respect to high awareness and relevance of climate change. In the passenger cabin, the focus is on both ecological and efficient lightweight construction. Due to the very high design freedom in combination with economical manufacturing costs and efficient production processes, combined with avoiding environmentally harmful phenolic resins at the same time, Sheet Molding Compounds (SMC) offer a high potential for application in the cabin sector. To date, polyester or vinyl ester based SMC semi-finished products with particulate flame-retardants have mainly been used in the cabin sector to meet the strict fire protection requirements (FST = Fire, Smoke, Toxicity). However, this requires very high contents of filler, which have a negative effect on the optical quality of the components (e.g. formation of streaks, not colorable) as well as on the achievable mechanical properties and the required high semi-finished product densities. This significantly limits the possible utilization for current SMCs in aircraft cabins. Most applications in visible components demand post-processing with a cost-intensive and environmentally harmful additional coating due to the poor optical quality. In addition, current SMC semi-finished products are exclusively opaque.

In the joint project “TraNa”, novel flame-retardant and at the same time translucent or homogeneously colorable SMC formulations are developed for the application in aircraft cabins. An epoxy resin system is used as matrix. The fire protection requirements should be fulfilled by a combination of conventional particulate and liquid fire retardant additives, as well as newly developed Layered Double Hydroxides (LDH) nanoparticles.