Theme: Washable Graphene-based Conductive Coating: The Impact of TPU Segmental Architecture on its final performances
| Her research focuses on the development, characterization, and modelling of innovative polymer composites and nanocomposites with applications in textiles, biomedical, packaging, and aerospace sectors. She has contributed to national and international research projects on smart materials, antimicrobial coatings, and circular economy solutions. Dr. Improta is co-founder of Wolffia S.r.l., a startup focused on reusing industrial waste for sustainable innovation. She has published peer-reviewed articles, a book chapter, and several conference proceedings, and has presented her work at international scientific conferences. |
Abstract
| The development of sustainable, water-based conductive coatings is essential for advancing eco-friendly wearable and printed electronics [1,2]. A key challenge remains in achieving high electrical conductivity and wash durability, which depend heavily on the compatibility between the polymer matrix, conductive fillers, and the target substrate [3]. This study investigates a simplified approach to formulating washable conductive coatings [4] by directly integrating few-layer graphene (FLG, 2.5 wt%) into four different commercially available bio-based thermoplastic polyurethanes (TPUs), blended with polyvinylpyrrolidone (PVP). The focus is on understanding how the segmental architecture of each TPU affects filler dispersion, mechanical integrity, and electrical performance. The coatings were applied onto flexible substrates (fabric and paper) using a scalable bar-coating process and characterized for morphology, thermal behavior, conductivity, and wash resistance (Figure 1). Results reveal that the hard-to-soft segment ratio of the TPU plays a critical role in determining both filler distribution and substrate compatibility. TPUs with a higher hard segment content favor interaction with hydrophobic surfaces, while those with moresoft segments enhance adhesion to hydrophilic substrates. Increased soft segment content also improves the internal distribution of conductive fillers, promoting the formation of continuous percolation paths and higher conductivity. These findings highlight the importance of TPU segmental structure and hydrogen bonding in tuning coating performance. This comparative analysis offers practical insights for selecting optimal polymer matrices based on substrate type and application, supporting the development of durable, high-performance, and washable electronic textiles and paper-based devices. |