Broad-Spectrum Antimicrobial Polymer-Coated Fabrics via Commodity Polystyrene Upcycling

Polystyrene derived from styrofoam food containers was transformed into antimicrobial polymer coatings on cotton fabric via a facile chemical upcycling process. In a two-step sequence, commodity polystyrene was first subjected to initial halomethylation where the pendent phenyl rings of the polymer were functionalized quantitatively with CH2Cl moieties. Next, in our key fabrication step, in situ quaternization and cross-linking of the polymer with a rigid bifunctional tertiary amine were readily achieved under ambient conditions using a drop-and-dry approach on cotton to afford a polycation-coated fabric. Scanning electron microscopy analysis revealed cotton fibers that were coated with aggregated cationic polymer nanoparticles. The functionalized textile remained flexible and was found to exhibit broad-spectrum antimicrobial activity against a panel of Gram-negative and Gram-positive bacteria as well as fungal pathogens including the recently emerged multidrug-resistant Candida auris. This facile synthesis of microbicidal coatings on cotton fabric holds the potential to sustainably create functional wearables for the healthcare industry from cheaply available postconsumer commodity polymers.