A PhD thesis, Politecnico di Torino, assesses a number of bio-based molecules as PIN FRs for cotton: whey proteins / caseins, chitosan, DNA / nucleic acids recovered from agri-food wastes.
Extraction methods to recover these useful molecules from agri-food by-products were developed. Application to cotton fabrics by both aqueous impregnation and layer-by-layer were tested, as well as UV curing to improve durability in laundering. Synergies were demonstrated between nucleic acids and chitosan and between nucleic acids and caseins. The author notes that layer-by-layer application (resulting in a number of very thin, alternating, layers of different biomolecules) gives better fire performance but is not today developed at an industrial scale. Nucleic acids offer high PIN FR potential and the work carried out shows that industrial extraction from bio-wastes could provide a feasible and economic source.
“Biomacromolecules: A sustainable approach for the design of fire retardants for textiles”, A. Casale, PhD thesis, Politecnico di Torino, May 2017 http://dx.doi.org/10.6092/polito/porto/2673802