The wetting behavior of a hydrophobic rough surface is investigated on a surface fabricated by applying low surface tension materials such as silicone or fluoropolymer to polyester woven fabric consisting of multifilament yarns. The roughness factor of various woven fabrics can be calculated by Wenzel’s and Cassie–Baxter’s equations. For the fabrics treated with silicone or fluoropolymer, the Cassie–Baxter model was applied, showing a level of agreement for the fabric specimens non-textured filament fibers between the predicted contact angles and the measured values. More precisely, the fabrics treated with silicone or fluoropolymer represent the transitional state between the Wenzel type and the Cassie–Baxter type; that is, the fractional contact area between the water and air f₂ is greater than zero, and the sum of the fractional contact areas for solid–water f₁ and air–water f₂ is greater than 1. A surface with lower energy and higher roughness gave f₁ + f₂ close to 1 with smaller f₁ and larger f₂, which resulted in a high contact angle.

This study aims to develop a multifunctional fabric for antibacterial, superhydrophobic and conductive performance using a facile fabrication method. Conductive metal particles, copper and silver, were used as antibacterial agents as well as a means to create nanoscale roughness on the fabric surface. Subsequent hydrophobic coating with 1-dodecanethiol produced a superhydrophobic surface. The single metal treatment with Cu or Ag, and the combined metal treatment of Cu/Ag were compared for the multifunctionality. The Cu/Ag treated fabric and the Cu treated fabric showed a bacteriostatic rate ≥ 99% and a sterilization rate ≥ 99% against S. aureus, suggesting a higher antibacterial activity against the Gram-positive bacteria. In contrast, the Ag treated fabric showed a lower antibacterial effect regardless of the bacteria type. With regards to conductivity, the single metal treated fabric did not exhibit conductivity; however the Cu/Ag treated fabric showed a high level conductivity with a surface resistivity of 25.17 ± 8.18 Ω sq⁻¹ and 184.38 ± 85.42 Ω sq⁻¹ before and after hydrophobic coating, respectively. Fabrics treated with Cu and Cu/Ag particles (with hydrophobic coating) displayed superhydrophobic characteristics with the contact angle of 161–162° and the shedding angle of 7.0–7.8°. The air permeability decreased after the particle treatment as the particles blocked the pores in the fabric. However, the water vapor permeability and tensile strength were not significantly affected by the particle treatment. This study is significant in that a multifunctionality of antibacterial effect, superhydrophobicity, and conductivity was achieved through the facile processes for metal nanoparticle attachment and hydrophobic coating. The multifunctional fabrics produced in this study can be practically applied to self-cleaning smart clothing, which has reduced laundering need, without hygiene concerns.

This study compared the waterproof and breathable properties of clothing made from an electrospun nanoweb with those made from a conventional waterproof-breathable fabric, in order to determine the optimal environment for using electrospun nanoweb laminate with the most favorable performance for outdoor clothing. The water resistance and water vapor transmittance of the fabrics were evaluated under a range of conditions that simulate the clothing microclimate. In addition, the clothing microclimate and subjective sensations were examined under normal and rainy atmospheric conditions. The results showed that the nanoweb laminate had a higher water vapor transmission rate but lower water resistance than the polytetrafluoroethylene laminate. Results from the water penetration tests however suggest that water resistance may be sufficient to prevent wetting by rain. The wearing test revealed that nanoweb laminated clothing provided a more comfortable clothing-microclimate than polytetrafluoroethylene laminated clothing in a normal, warm environment similar to that when the wearer is exercising or sweating. In the rainy test conditions, no difference was observed between the polytetrafluoroethylene and the nanoweb laminated clothing in any of the measured variables.

Polyurethane (PU) is a unique polymeric material with excellent chemical and physical properties and is widely used in textile materials. There has been a need for superhydrophobic PU for wider applications, such as coating materials. In this research, SiO₂ nanoparticle (SNP) incorporated PU webs with superhydrophobic and breathable properties were prepared by one-step sol-gel electrospinning and post-treated with a non-fluorinated water repellent chemical, n-dodecyltrimethoxysilane (DTMS). SNPs were observed to be distributed evenly all over the fiber surfaces when 1–6 wt% SNP and tetraethoxysilane (TEOS)/acetic acid solution were added. TEOS was hydrolyzed to form larger nanoparticles while developing cross-linking with aromatic groups of the PU matrix. Interestingly, the addition of 20 nm SNPs was thought to act as nucleating seeds for enhanced hydrolysis of TEOS within the PU matrix. The hierarchical surface roughness consists of different sized SNPs and polymer beads, which resulted in superhydrophobicity with water contact angles as high as 157° and shedding angles as low as 5°. Laminating PU/SNP/DTMS webs onto polyester fabrics maintained the air permeability and water vapor transmission rate, which proves the potential of the developed PU/SNP/DTMS webs for practical applications as textile laminate materials with simple processing.