Zeolitic imidazolate framework decorated bacterial cellulose coating for enhancing particulate filtration and adsorption from liquid and vapour phases of woven fabric

Abstract

There is currently a timely need for protective textiles used against hazardous chemical warfare agents (CWAs) to move away from fluorinated polymers due to the increasing environmental and health concerns associated with perfluoroalkyl substances. This represents a technical challenge as fluorinated surfaces are important to impart hydrophobicity and oleophobicity to prevent liquid CWAs from reaching the skin level. In this work, we report an alternative approach to increase the adsorption capacity and barrier properties of textiles through metal–organic framework decorated nanocellulose. Bacterial cellulose (BC) was decorated with zeolitic imidazolate framework (ZIF-67) through the growing of ZIF-67 in the presence of BC. ZIF-BC possessed a higher surface area of ∼400 m² g⁻¹, higher n-hexane and ethanol vapour sorption, as well as higher Congo red liquid sorption capacities compared to neat BC. When used as an ultra-low grammage coating for an open porous woven textile substrate, ZIF-67 decorated BC was able to offer an enhanced barrier performance in terms of reduced air permeability and increased aerosol particulate filtration efficiency (up to 97% for PM₁ at a coating grammage of 1 g m⁻²) without sacrificing moisture transmission rate compared to uncoated woven textile and woven textile decorated with ZIF-67 only. Our work opens up new possibilities in the fluorine-free coating of protective textiles.