{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T00:40:08Z","timestamp":1759970408922,"version":"build-2065373602"},"reference-count":48,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2025,1,16]],"date-time":"2025-01-16T00:00:00Z","timestamp":1736985600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>Smart textiles provide a significant technological advancement, but their development must balance traditional textile properties with electronic features. To address this challenge, this study introduces a flexible, electrically conductive composite material that can be fabricated using a continuous bi-component extrusion process, making it ideal for sensor electrodes. The primary aim was to create a composite for the filament\u2019s core, combining multi-walled carbon nanotubes (MWCNTs), polypropylene (PP), and thermoplastic elastomer (TPE), optimised for conductivity and flexibility. This blend, suitable for bi-component extrusion processes, exemplifies the role of advanced materials in combining electrical conductivity, mechanical flexibility, and processability, which are essential for wearable technology. The composite optimisation balanced MWCNT (2.5, 5, 7.5, and 10 wt.%) and TPE (0, 25, and 50 wt.%) in a PP matrix. There was a significant decrease in electrical resistivity between 2.5 and 5 wt.% MWCNT, with electrical resistivity ranging from (7.64 \u00b1 4.03)104 to (1.15 \u00b1 0.10)10\u22121 \u2126\u00b7m. Combining the composite with 25 wt.% TPE improved the flexibility, while with 50 wt.% TPE decreased tensile strength and hindered the masterbatch pelletising process. The final stage involved laminating the composite filament electrodes, with a 5 wt.% MWCNT\/PP\/(25 wt.% TPE) core and a TPE sheath, into a textile triboelectric impact detection sensor. This sensor, responding to contact and separation, produced an output voltage of approximately 5 V peak-to-peak per filament and 15 V peak-to-peak with five filaments under a 100 N force over 78.54 cm2. This preliminary study demonstrates an innovative approach to enhance the flexibility of conductive materials for smart textile applications, enabling the development of triboelectric sensor electrodes with potential applications in impact detection, fall monitoring, and motion tracking.<\/jats:p>","DOI":"10.3390\/polym17020210","type":"journal-article","created":{"date-parts":[[2025,1,16]],"date-time":"2025-01-16T04:55:19Z","timestamp":1737003319000},"page":"210","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Development of Thermoplastic Bi-Component Electrodes for Triboelectric Impact Detection in Smart Textile Applications"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6303-7079","authenticated-orcid":false,"given":"David Seixas","family":"Esteves","sequence":"first","affiliation":[{"name":"Department of Mechanical Engineering, Faculty of Engineering, University of Porto, 4200-465 Porto, Portugal"},{"name":"CeNTI, Centre for Nanotechnology and Advanced Materials, 4760-034 Vila Nova de Famalic\u00e3o, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0781-7147","authenticated-orcid":false,"given":"Amanda","family":"Melo","sequence":"additional","affiliation":[{"name":"CeNTI, Centre for Nanotechnology and Advanced Materials, 4760-034 Vila Nova de Famalic\u00e3o, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1472-5304","authenticated-orcid":false,"given":"Bruno","family":"Peliteiro","sequence":"additional","affiliation":[{"name":"CeNTI, Centre for Nanotechnology and Advanced Materials, 4760-034 Vila Nova de Famalic\u00e3o, Portugal"}]},{"given":"Nelson","family":"Dur\u00e3es","sequence":"additional","affiliation":[{"name":"CeNTI, Centre for Nanotechnology and Advanced Materials, 4760-034 Vila Nova de Famalic\u00e3o, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3538-5804","authenticated-orcid":false,"given":"Maria C.","family":"Paiva","sequence":"additional","affiliation":[{"name":"Department of Polymer Engineering, IPC\u2014Institute for Polymers and Composites, University of Minho, 4800-058 Guimar\u00e3es, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5295-5648","authenticated-orcid":false,"given":"Elsa W.","family":"Sequeiros","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Faculty of Engineering, University of Porto, 4200-465 Porto, Portugal"},{"name":"LAETA\/INEGI\u2013Institute of Science and Innovation in Mechanical and Industrial Engineering, 4200-465 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,1,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Van Langenhove, L. 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