Durable and breathable ZnO/graphene-coated fabrics for enhanced BQR protection

Abstract

This work developed a new strategy to create active protection against chemical, biological, radiological and nuclear (CBRN) threats, based on polyurethane-based coatings for outer (water and oil-repellency) and inner (CBRN protection) functionalization of fabric. The internal coatings were functionalized with varying concentrations of zinc oxide nanoparticles (ZnO) and/or graphene nanoplatelets (Gf) and carefully spread onto a military-grade camouflage fabric using a knife coating methodology. Hence, a new double-layered system was created consisting of one double-coated fabric combined with a lining knitted fabric. Thereafter, its structural, mechanical, and thermal properties were evaluated, along with breathability and moisture management capacity. Preliminary CB protection assessment of the coated fabrics included evaluation of chemical penetration resistance and repellence (against 30% (v/v) H₂SO₄ and 10% (w/v) NaOH; ISO 6530), antibacterial activity against Staphylococcus aureus and Escherichia coli (ISO 22196), and antiviral activity using the bacteriophage MS2 as a surrogate of the SARS-CoV-2 virus (ISO 18184). The performance of the functionalized fabrics was assessed against chemical and biological warfare agents following the NATO standard AEP-38, and against high-voltage emission of X-rays. Finally, the attenuation of the fabrics was also tested analysing their response to alpha radiation (e.g. Am-241) and beta radiation (e.g. C-14, Sr-90/Y-90, CI-36 and Cs-137) generated by reference planar sealed sources. In summary, the produced coated fabrics are combined with specific linings following a rationale that enables the development of active, yet comfortable, protective garments suitable for both military and civilian applications. For the first time, to the best of our knowledge, scalable, promising and cost-effective solutions offering BQR protection simultaneously are here proposed.