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Flexible strain sensors have become a key component of intelligent wearable electronics. However, the fabrication of strain sensors with wide workable strain ranges and high sensitivity remains a great challenge. Additionally, the rapid development of polymer composites based strain sensors has produced a large amount of e-waste. Therefore, the development of strain sensors with wide strain sensing ranges and high sensitivity based on degradable materials is necessary. In this work, a silicone blocked polyurethane (Si-BPU) with high stretchability and degradability was synthesized and composited with carbon nanotubes (CNTs) to fabricate fibrous strain sensors. The synthesized 0.5% Si-BPU exhibited good biodegradability with a weight loss of 16.47% in 42 days. The Si-BPU/12CNTs fiber based strain sensor achieved a sensing range of 0%–353.3% strain, gauge factor (GF) of 206.3 at 250% strain and of 4,513.2 at 353.3% strain, and reliable stability under 10,000 repeated stretching-releasing cycles. Moreover, the Si-BPU/12CNTs strain sensor showed rapid response time (< 163 ms) and was capable of monitoring various human body movements (elbow bending, finger bending, breath, and swallow). In consequence, this work provides a new and effective strategy for the development of sustainable wearable electronic devices. [ABSTRACT FROM AUTHOR]

High-performance electromagnetic interference (EMI) shielding material that that can function properly under extreme working conditions is critical for their practical applications. Herein, flexible and highly conductive meta-aramid (PMIA) nonwoven fabrics were fabricated by combining polydopamine (PDA) modification and electroless silver plating. The PDA modification greatly enhanced the efficient deposition of silver nanoparticles (AgNPs) and the interfacial cohesion between the AgNPs and the PMIA fibers. The silver-coated PMIA nonwoven fabric exhibited an electrical conductivity as high as 0.29 Ω/sq, an excellent EMI shielding effectiveness (SE) of 92.6 dB and a high absolute EMI SE of 8194.7 dB cm2 g−1. In addition, the silver-coated PMIA nonwoven fabric maintained high electrical conductivity and EMI SE after being subjected to washing, bending and torsion deformations, high/low temperature, strong acidic/alkaline solutions and different organic solvents. These results have clearly demonstrated that PMIA nonwoven fabric can be made highly electrically conductive by using a simple and highly scalable method. It holds great promise for the applications in EMI shielding materials that can be used in various harsh conditions. [ABSTRACT FROM AUTHOR]