Photodegradation resistance and flammability of bio-based wood-nanoclay-polyurethane foam nanocomposites

Rigid polyurethane foams (RPUF) filled with lignocellulosic fillers have gained considerable interest due to their mechanical performance and eco-friendly characteristics. However, their flammability and photodegradation resistance properties still need further improvement, which may be achieved by incorporating various particles. This study investigated the effect of adding 2.5% of wood flour and 5%-15% of an organophilic nanoclay (relative to the wood flour weight) on the RPUF morphology, density, compressive strength, thermal stability, flammability, and photodegradation resistance. The addition of wood flour and nanoclay made the RPUF cells more rounded and disrupted but did not affect density. The compressive properties were adversely impacted. Nevertheless, the nanoclay significantly improved both flammability and photodegradation resistance compared to the neat RPUF. Graphical Abstract