Influence of silica aerogels on fabric structural feature for thermal isolation properties of weft-knitted spacer fabrics

Textile clothing coated with silica aerogels has the potential of thermal insulation performance for heating and cooling. This work investigated the thermal isolation properties of untreated and treated three-layered weft-knitted spacer fabrics with different thicknesses (2mm, 3mm, and 4mm) by using silica aerogels. Three samples of spacer fabrics (300GSM, 350GSM, 540GSM) were coated with nanoporous silica aerogel at a 26 degrees C temperature and then kept for aging, exchanging the solvent, surface modification. The characteristics, for example, thermal resistance, thermal conductivity, yarn arrangement angle, porosity, and air permeability of spacer fabric samples, were investigated. Scanning electron microscopy analysis and Fourier transform infrared spectroscopy-attenuated total reflection test were conducted to explore the surface morphology and surface changes initiated by the silica coating. The experimental results indicated that the treated weft-knitted spacer fabrics with 350GSM have a higher thermal resistance of 0.09131 m(2) K W-1, higher porosity ratio, higher air permeability, higher arrangement angle, and lower density. The statistical analysis also verified the significant performance (p = 0.000) of treated fabric samples at the 0.05 level.