Polypyrrole-modified multi-functional coatings for improved electro-conductive, hydrophilic and flame-retardant properties of polyamide 66 textiles

Multi-functional textiles have received much attention in the technical textile field for their novel functionalities available in a single substrate. Polyamide 66 (PA66), being an engineering polymer with excellent physio-mechanical properties, exhibits immense possibilities to be developed as a multifunctional textile substrate. In this work, multi-functional polyamide 66 (PA66) textiles equipped with enhanced electro-conductive, hydrophilic and flame-retardant properties were developed via in situ polymerization of pyrrole monomer onto the PA66 fabric surfaces. Meanwhile, various formulations comprised of phytic acid (PA), chitosan (CS), graphene oxide (GO) and Na-metaborate (B) along with the pyrrole also experimented with a goal to study the contribution of each compound onto the desired properties and finally, to come up with a suitable formulation. Among these formulations, only pyrrole containing formulation (i.e., PA66-PPy) demonstrated a significant improvement in all three desired functionalities, namely a noteworthy escalation in electrical conductivity (i.e., about a 43 times increase compared to the pure PA66), a semi-hydrophilic surface (i.e., water contact angle value was lowered from 124.3– 49.9°) and a substantial reduction in the peak heat release rate by 45%. Meanwhile, the formulation comprising both the pyrrole and phytic acid made the polyamide surface a super-hydrophilic one, whereas other formulations exhibited potential efficacy in attaining better flame retardancy, especially in terms of limiting oxygen index (LOI) values, vertical flame test data and char yield%.

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