不同基材上混合纳米导电油墨在干湿条件下电压与电阻的关系

摘要

石墨烯纳米片／银（GNP/Ag/SA）混合导电油墨在柔性电子中的应用日益广泛，但对于基材类型、溶剂配比与湿气暴露如何共同决定其在金属与聚合物基材上的电性能，人们的认识仍很有限。本文旨在阐明萜品醇含量（5T、10T、15T）以及铜（Cu）、聚对苯二甲酸乙二醇酯（PET）与热塑性聚氨酯（TPU）基材的性质，如何影响丝网印刷GNP/Ag/SA线路在干态与浸水后湿态下的电压、电阻与电阻率。本文在固定丁醇用量、改变萜品醇含量的条件下配制GNP/Ag/SA油墨，分别印刷于Cu、PET与TPU基材上，并通过电学测量、附着力评价与微观结构观察，把电阻率变化趋势与形貌、表面能及吸湿行为相联系。结果表明，Cu基材性能最佳：Cu 10T取得约1.2×10⁻⁵ Ω·m的最低干态电阻率，Cu 15T取得约2.0×10⁻⁵ Ω·m的最低湿态电阻率，这得益于致密且附着良好的微观结构。PET基材的电阻率较高，最高约达10⁻³ Ω·m，浸水后出现明显劣化；TPU基材在湿态下电阻率极高甚至无法测量，原因是油墨严重脱落与基材吸湿溶胀。上述结果凸显出，基材表面能与湿气响应对GNP/Ag/SA油墨在潮湿或涉水环境中的可靠性起着重要作用。

Abstract

Hybrid graphene nanoplatelet/silver (GNP/Ag/SA) conductive inks are increasingly used in flexible electronics, yet there is limited understanding of how substrate type, solvent composition, and moisture exposure jointly control the electrical performance on metal and polymer substrates. This work aims to clarify how terpinol content (5T, 10T, 15T) and substrate properties of copper (Cu), polyethylene terephthalate (PET), and thermoplastic polyurethane (TPU) influence voltage, resistance, and resistivity of screen-printed GNP/Ag/SA tracks under dry and post-immersion wet conditions. GNP/Ag/SA inks were formulated with fixed butanol and varied terpinol contents, printed on Cu, PET, and TPU, and characterized using electrical measurements, adhesion evaluation, and microstructural observations to relate resistivity trends to morphology, surface energy, and hygroscopic behavior. The Cu substrate showed the best performance, with Cu 10T achieving the lowest dry resistivity of approximately 1.2×10⁻⁵ Ω·m and Cu 15T the lowest wet resistivity of approximately 2.0×10⁻⁵ Ω·m, supported by dense, well-adhered microstructures. PET exhibited higher resistivity values up to about 10⁻³ Ω·m and clear degradation after water immersion, while TPU showed very high or unmeasurable resistivity in wet conditions caused by severe ink loss and hygroscopic swelling, highlighting the important role of substrate surface energy and moisture response in determining the reliability of GNP/Ag/SA inks for applications in humid or wet environments.