Multi-functional coating application of nano-TiO2 and Ti-MOFs on Workwear fabrics: Focus on thermal behavior, UV-resistant and functional properties

Abstract Protecting workers' health and promoting sustainable development are essential for improving occupational productivity and fostering economic growth across industrial sectors. Accordingly, this study aimed to develop multifunctional coatings for workwear fabrics using titanium dioxide (TiO₂) nanoparticles and titanium-based metal–organic frameworks (Ti-MOFs) to enhance thermal insulation, ultraviolet (UV) protection, and other functional properties. A conventional workwear fabric composed of 70% flax and 30% polyester was first prepared. Subsequently, coatings of the titanium-based MOF NH₂-MIL-125(Ti) and TiO₂ nanoparticles were deposited onto the fabric using an ultrasonic-assisted in situ growth method. The thermal performance of the coated fabrics was evaluated through thermal transfer measurements (thermal conductivity and thermal resistance), thermal analysis (TGA and DTA), and thermal imaging, together with the determination of the ultraviolet protection factor (UPF). In addition, key functional properties, including abrasion resistance, tear resistance, tensile strength, air permeability, and water vapor transmission and moisture absorption, were assessed. The results demonstrated that, compared with the untreated fabric, TiO₂ nanoparticle-coated and Ti-MOF-coated fabrics exhibited reductions in thermal conductivity of 45.5% and 22.7%, respectively, accompanied by increases in thermal resistance of 31.9% and 7.3%, respectively. The UPF value increased from 25.3 for the untreated fabric to 74.27 and 42.22 for the TiO₂ nanoparticle-coated and Ti-MOF-coated fabrics, respectively, indicating a substantial improvement in ultraviolet protection. In contrast, the air permeability of the Ti-MOF-coated fabric decreased relative to that of the untreated sample. Overall, the TiO₂ nanoparticle coating demonstrated greater potential for improving the thermal insulation performance of workwear fabrics, whereas the Ti-MOF coating exhibited superior potential for enhancing ultraviolet protection. Nevertheless, further comprehensive investigations are required to validate the practical applicability and long-term performance of these multifunctional coatings under real occupational service conditions.