Water-Borne Carbonaceous Coatings on Conducting Polymer-Modified Cotton Fabrics To Attenuate Electromagnetic Radiation

Textile-based shielding materials are gaining much importance for electromagnetic interference (EMI) shielding because of their increased flexibility compared to most existing materials. The multilayer-like architectures realized by coating textiles can be used strategically to enhance the attenuation of microwaves. Herein, we report a water-borne conductive coating capable of shielding both EM and UV radiation with good thermal stability for potential applications as smart textiles. This work tries to understand the effect of different textile pre-treatments to maximize the enhancements in properties. Cotton fabrics were initially subjected to in situ polymerization of aniline and pyrrole and subsequently coated with a carbonaceous layer containing graphene nanoplatelets and carbon nanofibers on both the sides. It was seen that both the conducting polymer layer and the carbonaceous coating work in tandem to enhance the thermal stability, UV blocking, and EMI shielding. The coated fabrics shows a shielding effectiveness of −22 dB at a thickness of 1.2 mm over a wide frequency range of 2.6–26.5 GHz, a limiting oxygen index of 26%, and remarkable UV-blocking properties with a blocking of 99.99%. Both the coating and the pre-treatment do not alter the fabric’s wettabilitythe surface remains hydrophilic. The coating rendered the fabric with conductivity values showing a four-order jump from the control sample. The samples show a shielding effectiveness of −22 dB, accounting for more than 99% of the incident radiation being attenuated. The attenuation happens via an absorption-dominated mechanism. The coated textile exhibits excellent heat dissipation properties, with temperatures dropping from as high as 147 to 41 °C in just 60 s.