Development of Superhydrophobic Surface for Medical Textiles

The objective of this study was to fabricate superhydrophobic surface with superhydrophobic property using nanoparticles and water-repellent agents for medical textiles. The wettability of the super hydrophobic surface was compared to that of other materials having a variety of roughness and surface energy. Microstructures were fabricated with 100% PET textiles having various yarn thickness and yarn finishing. Nano-sized structures were fabricated by finishing the PET textiles with CNTs nanoparticles using water-repellent agent. Contact angle (CA), contact angle hysteresis and shedding angle analysis were evaluated by Theta Lite contact angle meter (attension, Finland). Also, breathable waterproof properties were measured by water vapor transmission rate (ASTM 96-CaCl2) and air permeability (ISO 9237-1995). The results indicate that the super hydrophobicity was strongly influenced by the binary structure having nano-scaled roughness than by the chemical composition of surface. It was proven that the shedding angle, the angle at which a water droplet rolls off the surface, was reasonable method to analysis the super hydrophobic properties. Also, it was shown that all of the water-repellent agents and nano-particles did not decrease air permeability and water vapor transmission rate noticeably. The DTY sample treated with CNTs exhibited the highest super hydrophobic properties, having static contact angle of 160° and shedding angle of 4.4°. These results indicated that the long nanofiber shape of carbon nano tubes successfully maintained the trapped micro sized air layers like a papillae of lotus leaf.