Covalent Functionalization of Kevlar Fabric with Graphene Nanosheets

Abstract

Whilst technical textile requirements for personal protecting clothing have dramatically increased during the past years due to the climate and health crisis, as well as the human factor, garment industry is in search of new fabrics that will meet these emerging needs. Aiming in the realization of superior fabrics performing under extreme environmental and operational conditions, carbon nanostructures and graphene-related 2D nanomaterials offer their mechanical strength and functionalization capability in this new challenge. 1 However, most techniques developed for the hybridization of fabric fibers with carbon nanostructures and related 2D nanomaterials are based on physisorption and surface coating. Herein, we present a protocol for the covalent modification of Kevlar fibers in order to generate free amine groups on their aromatic rings that can be chemically manipulated to covalently attach graphene nanosheets. In particular, Friedel-Crafts type nitration of Kevlar fibers, followed by hydrogenation to furnish amine moieties, allows condensation with a small amino acid that serves as the connector with oxidized graphene flakes (Figure 1). 2 Optimized conditions and in depth spectroscopic study are provided that collectively offer an easy-monitoring protocol of each step and allow the transfer of this knowledge to other related 2D nanomaterials. Considering the ability of 2D nanomaterials to carry designed properties via functionalization, this methodology allows the realization of multipurpose custom fabrics with enhanced qualities of choice. Partial financial support by the European Regional Development Fund of the European Union and Greek national funds through the Operational Program Competitiveness, Entrepreneurship and Innovation, under the call RESEARCH-CREATE-INNOVATE (project code: Τ2EDK-01316) is acknowledged. References [1] I. K. Sideri, N. Tagmatarchis, Mater. Horiz. , 2021, 8, 3187. [2] Manuscript in preparation. Figure 1