摘要
Smart textiles require conductors that maintain electrical stability under repeated deformation and laundering while preserving textile-like softness. Here, we develop a poly(imide-urethane) (PI–PU) copolymer that combines the high-temperature dimensional stability, abrasion, and dielectric properties of polyimide (PI) with the elasticity of polyurethane (PU). The PI–PU copolymer was synthesized from polytetramethylene ether glycol (PTMEG 3000), 3,3′,4,4′-benzophenonetetracarboxylic dianhydride (BTDA), and m-xylylene diisocyanate (XDI) in N-methyl-2-pyrrolidone (NMP) under nitrogen; optional melamine crosslinking improved mechanical robustness. Conductive pastes were obtained by dispersing 62 wt% Ag powder in the PI–PU using a high-speed vacuum defoaming mixer. Printed traces on TPU film exhibited a resistivity of 3.5 × 10−5 Ω cm and negligible resistance change after 20 % elongation and recovery (0–8 % variation, best case 0 %). After AATCC 135 laundering 50 times, the resistance on knitted and woven laminates increased modestly from ∼2.0 to 2.8 Ω to 5.1–5.5 Ω, indicating durable conductivity and superior wash-wear resistance compared with a neoprene-based benchmark. The results demonstrate that PI–PU/Ag is a promising platform binder for printed circuits in wearable electronics, enabling stable signal transmission under cyclic strain and laundering.
•A new elastic conductive slurry from polymer polymerization, material ratio, homogenization technology, and process design.•The basic slurry in this study is a high-strength elastic PI-PU material with high hardness on the surface, and surface protection is required during use.•The PI-PU elastic conductive paste in this study has lower resistivity (3.5 × 10−5 Ω‧cm).•The PI-PU copolymer has a lower elastic resistance variation rate (<10 %).•The PI-PU conductive slurry has better washing/resistance (50 times).