Citation

Chatterjee S, Shanmuganathan K, Kumaraswamy G. ACS Appl. Mater. Interfaces 2017; 9(51): 44864-44872.

Copyright

(Copyright © 2017, American Chemical Society)

DOI

10.1021/acsami.7b16808

PMID

29206442

Abstract

Polymeric foams used in furniture and seating applications for automotives and aircraft rely on incorporation of environmentally hazardous fire retardant additives to meet fire safety norms. This has occasioned significant interest in novel approaches to the elimination of fire retardant additives. Foams based on polymer nanocomposites or based on fire retardant coatings show compromised mechanical performance and require additional processing steps. Here, we demonstrate a one-step preparation of a fire retardant ice-templated inorganic/polymer hybrid that does not incorporate fire retardant additives. The hybrid foams also exhibit excellent mechanical properties. They are elastic to large compressional strain, despite the high inorganic content. They also exhibit tunable mechanical recovery, including viscoelastic "memory". These hybrid foams are prepared using ice-templating, that relies on a green solvent, water, as a porogen. Since these foams are predominantly comprised of inorganic, they exhibit exceptional fire retardance in torch burn tests and are self-extinguishing. After subjecting to a flame, the foam retains its porous structure and does not drip or collapse. In microcombustion calorimetry, the hybrid foams show a peak heat release rate that is only 25% that of a commercial fire retardant polyurethanes. Finally, we demonstrate that ice-templating to prepare hybrid foams is compatible with the use of different inorganic colloids, including cheap commercial materials. We also demonstrate that ice-templating is amenable to scale up, without loss of mechanical performance or fire retardant properties.

Language: en