Jiangtao Xu

AgNps-PVA–coated woven cotton fabric: Preparation, water repellency, shielding properties and antibacterial activity

Nowadays, there is a large demand for smart textiles by consumers. Smart textiles have different functions, and can provide comfort, safety and protection. In this study, electro-conductive woven cotton fabric is prepared in two steps. The cotton fabric samples are first impregnated and padded with a polyvinyl alcohol solution of 5% for multiple cycles (1, 3, 5 and 7 cycles) and dried. Then, silver nanoparticles are deposited onto the fabric through magnetron sputtering technology. The coated samples are examined using a Fourier transform infrared spectrometer, scanning electron microscope and X-ray diffractometer. The ultraviolet blocking, infrared reflection, electromagnetic shielding, and antibacterial properties are evaluated, as well as the contact angle, light transmittance and electrical conductivity. The results show that a polyvinyl alcohol film is successfully formed and the cotton fabric fibers are stuck together through hydrogen bonds. The light transmittance is increased after the polyvinyl alcohol pretreatment. After undergoing seven cycles of coating with polyvinyl alcohol, the silver nanoparticles-coated samples show large contact angle of 127.6°, excellent ultraviolet blocking property, a high infrared reflectivity of 30%, electrical resistivity of 1.46 × 10–6 Ω·m, electromagnetic interference shielding effectiveness of −20 dB and antibacterial efficacy of >99.5%. Compared to the untreated and silver-coated cotton without impregnation of polyvinyl alcohol, the silver nanoparticles–polyvinyl alcohol-coated cotton fabric sample has excellent performance, which makes it a promising textile with a multitude of protective properties.

Preparation and characterization of copper-coated polyester fabric pretreated with laser by magnetron sputtering

Laser treatment is a high-efficiency coating process with many advantages of stable performance, convenient operation and environmental friendly. In this study, an efficient method for the pretreatment of polyester fabric, based on exposure to the output from a CO2 laser, is investigated. Polyester fabrics were treated by laser and then copper films were coated on the surface of treated polyester fabrics by magnetron sputtering method. Copper-coated polyester fabrics were characterized by XRD and SEM. Contact angle, heat generation and electrical conductivity of copper coated polyester fabric were tested. The electrical conductivity, UPF value and contact angle of copper-coated polyester fabric with pretreatment of 6.5 W lasers are 0.239 Ω/sq, 147.4, and 128.5°, respectively. The temperature of copper-coated fabric can be kept at 25.8℃ using only 5 V. The results suggest that the copper-coated polyester fabric with pretreatment of laser has excellent electrical conductive property, hydrophobicity, UV blocking, and heat generation properties. The adhesion strength between copper coating and fibers is improved after laser treatment. Laser can be potentially used in pretreatment of fabrics before coating in the future.

Photo-thermal conversion and thermal insulation properties of ZrC coated polyester fabric

Zirconium carbide (ZrC) films are deposited onto polyester fabric through magnetron sputtering. The deposited films are then examined by using field scanning electron microscopy and energy dispersive X-ray spectroscopy. The photothermal conversion property, film thickness, infrared reflectance and transmittance, and thermal conductivity are also evaluated. The results show that the highest far-infrared emissivity of polyester fabric deposited with ZrC is 0.9379. The ZrC deposited samples showed a small increase in thermal conductivity with a difference of 0.0611W/m·K, and a higher photothermal conversion efficiency with a temperature increase of 27.5 °C in 100 s, when the thickness of the ZrC film is 1920 nm. These therefore indicate that coating fabrics with ZrC through magnetron sputtering is an environmentally friendly means to produce textiles with photo-thermal conversion and heat insulation properties.