Flexible Piezoresistive Pressure Sensors Based on Graphite-Loaded tPLA/TPU Composites: Composition and Geometry Optimization
IEEE Sensors Letters, cilt.10, sa.10, 2026 (ESCI, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 10 Sayı: 10
- Basım Tarihi: 2026
- Doi Numarası: 10.1109/lsens.2026.3727318
- Dergi Adı: IEEE Sensors Letters
- Derginin Tarandığı İndeksler: Emerging Sources Citation Index (ESCI), Scopus
- Anahtar Kelimeler: conductive polymer composite, flexible pressure sensor, graphite-loaded composite, piezoresistive pressure sensor, Sensor materials
- Süleyman Demirel Üniversitesi Adresli: Evet
Özet
Flexible piezoresistive pressure sensors play a critical role in applications requiring low-cost fabrication, mechanical compliance, and high adaptability. These sensors are widely employed in robotic tactile systems, object manipulation monitoring, and smart surface technologies. In this study, a low-cost elastomeric piezoresistive pressure sensor was developed using graphite-loaded blends of tough polylactic acid (tPLA) and thermoplastic polyurethane (TPU, Shore hardness: 92A), prepared via temperature-controlled magnetic stirring. A three-stage parametric optimization was performed, including: 1) polymer concentration (15 and 20 wt%), processing temperature (50 °C–100 °C), and processing time (30–240 min); 2) tPLA:TPU volumetric ratios (10:0, 9:1, 8:2, 7:3, 6:4, 5:5, 0:10, v/v); and 3) graphite loading (25%–75% w/v). The optimal formulation—15 wt% tPLA processed at 100 °C for 240 min with 65 wt% graphite loading—exhibited electrical resistance in the range of 3–30 Ω and demonstrated a stable piezoresistive response under applied pressure. The sensor showed high sensitivity in the 0–500 kPa range, while approaching saturation above ∼1000 kPa due to the compression limit of the polymer matrix. Furthermore, the sensor maintained structural integrity and repeatable electrical response under cyclic loading conditions. These results indicate strong potential for low-cost, scalable, and flexible pressure sensing applications in robotics and smart systems.