<p>Modern consumer electronics products are developing rapidly and advancing toward lightweight, high integration, and flexibility. The mechanical flexibility of electronic products represents a significant trend in electronics development. However, flexible electronics impose stringent requirements on interconnect materials. In this study, polyurethane prepolymers were synthesized using 4,4’-diphenylmethane diisocyanate (MDI) and polyethylene glycol adipate (PHA) as raw materials, with methyl ethyl ketoxime employed as a blocking agent to prepare thermosetting polyurethane-based conductive silver pastes at varying MDI-to-PHA ratios. The results indicate that the MDI-to-PHA ratio significantly influences the properties of the silver paste. The polyurethane synthesized at an MDI-to-PHA ratio of 1:1.3 exhibits a relatively low polydispersity index (PDI) and achieves the lowest resistivity of 8 × 10⁻⁸ Ω·m. After 20 bending cycles, this paste maintains resistivity within 175% of its initial value. The fluctuation of the printed grid line width on the silicon wafer is less than 1&#xa0;μm, and the contact resistance is 0.027 mΩ·cm²; similarly, the paste with an MDI-to-PHA ratio of 1:2 sustains resistivity within 150% after 20 bends, demonstrating excellent bend resistance and flexibility, which renders it suitable for flexible electronics applications.</p>