Fibre-based composites from the integration of metal–organic frameworks and polymers

The integration of metal–organic frameworks (MOFs) with polymer fibres enables the formation of fibrous composite materials with advantages over traditional single-component polymer films and mixed-matrix membranes. In comparison with mixed-matrix membranes, MOF–polymer fibrous composites offer improved molecular transport through the material and easier access to the active sites of MOFs. These attributes make fibrous composites appealing for clothing, personal protective equipment, air purification and filtration, biomedical equipment and delivery of therapeutics, along with detection and sensing applications. In this Review, we outline approaches for the incorporation of MOFs into, or onto, polymer fibres and present some applications for MOF–polymer fabrics. The integration of MOFs and polymers can either occur prior to fibre formation (namely, MOF-first), via particle deposition (resulting in either covalent or non-covalent attachment) of MOFs to the fibre or by in situ MOF growth after fibre formation (namely, fibre-first). We focus on the structure–processing–activity relationships — for example, MOF loading, MOF crystal size, polymer concentration and processing parameters — that impact the behaviour of fibrous composites. We conclude with a discussion of research avenues that can advance this burgeoning field. Composites made from metal–organic frameworks and polymer fibres are gaining popularity in many applications because of their tailorable morphologies and properties. This Review summarizes various methods for fabricating these composites, explores structure–processing–activity relationships and discusses future research opportunities.