Functional CuI–PVA hybrid sol–gel coatings for cotton fabrics: Synthesis, characterization, and antibacterial performance

This work reports the development of a hybrid CuI–PVA/siloxane sol–gel finishing for antibacterial cotton fabrics. CuI particles were synthesized by a sonochemical route, stabilized in poly(vinyl alcohol) (PVA), and incorporated into a GPTMS/TEOS-derived sol–gel matrix. The resulting dispersions, containing 2.04 and 4.08 wt% CuI–PVA, were applied to cotton by a conventional pad–dry–cure process. The CuI–PVA dispersions and the treated fabrics were characterized by FTIR and Raman spectroscopy, SEM-EDS, and washing durability tests. The results indicate the formation of a siloxane network that anchors the CuI–PVA phase onto the cotton surface without compromising the morphology of the substrate. Both formulations exhibited marked antibacterial activity against Staphylococcus aureus ATCC 6538 and Escherichia coli ATCC 11229, with bacterial reductions higher than 99% under the tested conditions. This antibacterial performance was substantially retained after three ISO 105-C10 washing cycles. Overall, the proposed CuI–PVA/siloxane system represents a simple and scalable proof-of-concept strategy for imparting antibacterial functionality to cotton fabrics intended for hygienic and technical applications.