Milliken, of Spartanburg, South Carolina, says that the fabrics will be functional, reactive and self-decontaminating, and will provide protection to wearers from chemical, biological, radiological and nuclear (CBRN) threats, while keeping them comfortable.
The fabrics will be made using Skokie, Illinois-based Numat's Sentinel MOFs. Numat says that Sentinel MOFs precisely and effectively remove contaminants, such as ammonia (NH3), nitrogen dioxide (NO2), and chlorine (Cl2), from the environment. It adds that their high selectivity and large surface area enable the MOFs to outperform existing technologies for the filtration of such chemicals.
The Chief Executive Officer (CEO) of Numat, Ben Hernandez, says: “By combining Numat’s highly advanced MOF technology platform with Milliken’s textile technology and scale, we are delivering sustainable, high-performance solutions that protect those who protect us.”
MOFs consist of metal ions or clusters of metal ions that form structures with organic ligands, ions or molecules based on chains of hydrogen, boron, carbon, nitrogen and oxygen atoms, which typically form one, two, three or four chemical bonds (mono-, di-, tri or tetravalent materials). MOFs are crystalline and a key feature is that they are often porous, and as such crucially exhibit extremely large surface areas.
Alongside their high surface areas, MOFs typically have high porosities (up to 90% free volume) and consist of small uniform channels, which typically measure on the sub-nanometre scale.
Owing to the ability of chemists to make MOFs from a wide combination of metals and ligands, there is a huge range of material compositions and structures from which to choose. The metal ions, for instance, dictate the orientation and the number of ligands in the MOF, and thereby the size and shape of the pores.
The wide choice allows for selection according to the required chemical functionalities and internal surface properties. Pores, for instance, can be nanoscale (radius less than 2 nm) or meso- or macro-scale (radius more than 25 nm).
Finally, MOFs are thermally stable, capable of use at 300°C and more.