Conductive polymer composites with carbonic fillers: Shear induced electrical behaviour

Emerging Functional Polymer Composites for Tactile Sensing

In recent years, extensive research has been conducted on the development of high-performance flexible tactile sensors, pursuing the next generation of highly intelligent electronics with diverse potential applications in self-powered wearable sensors, human-machine interactions, electronic skin, and soft robotics. Among the most promising materials that have emerged in this context are functional polymer composites (FPCs), which exhibit exceptional mechanical and electrical properties, enabling them to be excellent candidates for tactile sensors. Herein, this review provides a comprehensive overview of recent advances in FPCs-based tactile sensors, including the fundamental principle, the necessary property parameter, the unique device structure, and the fabrication process of different types of tactile sensors. Examples of FPCs are elaborated with a focus on miniaturization, self-healing, self-cleaning, integration, biodegradation, and neural control. Furthermore, the applications of FPC-based tactile sensors in tactile perception, human-machine interaction, and healthcare are further described. Finally, the existing limitations and technical challenges for FPCs-based tactile sensors are briefly discussed, offering potential avenues for the development of electronic products.

Nanostructured thin lignin-derived carbon sheets as excellent reinforcement fillers in polypropylene

In this article, natural alkali lignin was freeze-dried and then annealed at different temperatures to achieve lignin-derived carbons (LCs) with mesh-shape or sheet-like morphology, which were incorporated into polypropylene (PP) matrix by melt compounding. Owing to the significantly increased interfacial area and improved dispersion of the carbons in the polymer matrices, with the addition of only 2 wt% relatively low temperature annealed freeze-dried lignin-derived carbon (FD-LC), the obtained PP/LC composites show notably enhanced tensile mechanical properties, including markedly improved Young's modulus and remarkably increased elongation at break compared with those of neat PP. The enhancements brought by the nano-structured thin FD-LC sheets are far more impressive than that with the same loading of particulate as-received lignin-derived carbon (AR-LC). The FD-LC filled PP composites also have rough fractured surfaces with fiber pull-out near the interface, revealing the non-negligible toughening effect of the LC. In addition, the higher temperature annealed FD-LC filler induces the further reinforcement of the composites. For the FD-LC annealed at 900 °C, the corresponding composite possesses the highest Young's modulus of 668 MPa.

The sheet-like freeze-dried lignin-derived carbons act as advanced fillers for polypropylene composites with large interfacial areas and excellent mechanical properties.