Enhancing thermal conductivity of cotton fabrics with nanocomposite coatings

Heat transfer is vital for many textiles including sportswear, work uniform, shoes, bedding, and healthcare products. Such a process in fibrous materials is complex and often involves three main routes (conduction, convection and radiation), with the heat conduction being more significant than the other two. Conventionally, heat transfer in fabrics is adjusted mainly through changing fabric thickness, aerial density, porosity, or weave structure. Little attention has been paid to increasing the thermal conduction of fabrics through surface finishing with a thermally conductive material. Carbon nanomaterials, such as carbon nanotubes (CNTs) and graphene, have been recently reported to have excellent thermal conductivity. The thermal conductivity of multi-wall carbon nanotubes (MWCNTs) has been measured to be as high as 3000 W/mK. Graphene, a single layer of graphite, was recently reported to have even higher thermal conductivity. At room temperature, the thermal conductivity of a single-layer graphene was reported to be 5300 W/mK. Boron nitride (BN) is another thermal conductive material widely used as filler for making thermo-conductive adhesives, pastes, and greases. Hexagonal boron nitride (h-BN) is similar to graphite having a platelet structure, thus being soft and lubricious. h-BN has a high in-plane thermal conductivity of up to 300-600 W/mK.Herein we report on the effects of the composite coatings containing these three nano fillers (MWCNT, grapheme and BN) on the thermal transfer properties of cotton fabrics.