DNA (deoxyribonucleic acid) from fish waste (herrings) was combined in a one-step reaction with commercially available modified silicate (montmorillonite) nanoclay and tested as a PIN flame retardant in epoxy resin. Around 0.7% w/w DNA was integrated into the clay using clay as slurry and acetone solvent at pH2, expanding the d-space between clay layers by c. 50%.
The integration of DNA into the clay improves dispersion into and interactions with the epoxy resin, and contributes to flame retardancy because DNA is an organo-carbon phosphorus-based chemical. 2.5% loading of the DNA-clay product improved tensile strength, tensile modulus and toughness of the epoxy and reduced peak heat release rate (PHRR) by around 25%, in all cases compared to both epoxy without clay and to clay only, no DNA.
“Fish DNA-modified clays: Towards highly flame retardant polymer nanocomposite with improved interfacial and mechanical performance”, O. Zabihi et al., Nature Sci Reports, 6:38194, DOI: 10.1038/srep38194, 2017 https://polymerandfire.files.wordpress.com/2016/12/srep38194.pdf