Antibacterial Cotton Fabric with Fluorine-Free Superhydrophobicity and UV Protection via 3D Flower-Like TiO₂ Microparticles/PDMS Coating

The application of multifunctional textiles has been hindered due to several drawbacks such as the use of nanomaterials and toxic fluorinated compounds in their preparation process. These materials can cause serious environmental issues with long-term consequences and pose health risks to consumers. This study demonstrates the application of micron-sized 3D flower-like TiO₂ particles (3D-TiO₂) mixed with fluorine-free polydimethylsiloxane (PDMS) polymer in developing antibacterial, superhydrophobic, and UV protective cotton fabrics. To this end, 3D-TiO₂ particles were synthesized via a hydrothermal method and used as antibacterial and UV protective agents in the surface finishing of cotton fabric. The 3D-TiO₂/PDMS-coated fabric showed antibacterial efficacy against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) bacteria and did not exhibit cytotoxicity toward L929 fibroblast cells. The combination of hierarchical surface roughness of 3D-TiO₂ particles with low-surface energy PDMS binder produced superhydrophobicity, with a water contact angle (WCA) of 153.1° ± 4.9°. Moreover, the coated fabric exhibited an excellent level of UV protection, with an ultraviolet protection factor (UPF) of 213, indicating 145% enhancement compared with the untreated fabric. The surface characteristics of the coated fabric were thoroughly analyzed using SEM, EDX, and XPS techniques, and the relationships between the coating ingredients and the obtained functionalities were established. The outcomes of this study can contribute to the development of textiles with enhanced functionalities without the use of nanosized additives and harmful fluorinated chemicals.