Molecularly Engineered Degradable PCTPU–PAA Dielectrics With Boosted Carrier Mobility for Retina‐Mimic Neuromorphic Visual Sensors Toward Closed‐Loop Green Flexible Electronics

Conventional polyurethane-based dielectrics are mostly nondegradable fossil-derived materials lacking effective end-of-life management, leading to massive electronic waste and unsustainable life cycles-key barriers to the green transition of flexible electronics. Despite their desirable stretchability and self-healing, inherent limitations in dielectric polarization and interfacial modulation restrict optoelectronic performance, creating an unresolved trade-off between functionality and sustainability. Guided by green chemical engineering and circular economy principles, we designed a degradable polycarbonate-based thermoplastic polyurethane (PCTPU) by incorporating PC soft segments into the polyurethane backbone, and constructed a robust non-covalent hydrogen-bonding network via poly (amic acid) (PAA) blending to synergistically regulate dielectric polarization and interfacial compatibility. The PCTPU-PAA composite exhibits excellent mechanical performance and enhanced self-healing property. Notably, when integrated into organic neuromorphic visual sensors (ONeuVS), the composite enables a ∼7.6-fold enhancement in carrier mobility versus bare PCTPU sensors. It also endows ONeuVS with enhanced retinal-like photoresponsiveness, achieving 92.67% accuracy in handwritten digit recognition while reducing neural network training costs. Critically, a scalable multi-solvent stepwise separation method achieves efficient degradation and recovery, realizing a closed-loop life cycle. This work establishes a scalable molecular engineering strategy for high-performance, sustainable flexible dielectrics and devices, breaking the performance-sustainability trade-off and facilitating their large-scale green applications.