A review on the controlled preparation, structure-property relationship and application progress of multifunctional...

Metal nanoparticle-based polymer nanocomposites represent a versatile materials platform for integrating electrical, optical, thermal, catalytic, antimicrobial, and mechanical functionalities into lightweight, processable polymer matrices. However, their performance cannot be rationalized by metal identity or filler loading alone. Instead, it is governed by coupled structural descriptors, including nanoparticle size and morphology, dispersion state, interparticle spacing, interphase chemistry, network topology, and structural evolution under service conditions. This review summarizes recent advances in the controlled preparation, descriptor-property relationships, and application development of multifunctional metal nanoparticle-polymer nanocomposites from a descriptor-driven perspective. First, representative metal nanoparticles and polymer matrices are introduced and key concepts such as interphase effects, percolation behavior, and quantitative metrics for multifunctionality are outlined to establish a unified framework. Second, fabrication strategies, including in situ formation, ex situ incorporation, interfacial assembly, advanced patterning, green processing, and scalable manufacturing, are critically compared in terms of their capability to regulate key structural features. Third, the relationships among morphology, interphase-mediated transport, multifunctional coupling, predictive modeling, and long-term reliability are discussed to elucidate performance-limiting factors and design rules. Finally, applications in flexible and printed electronics, wearable sensors, energy conversion and storage, electromagnetic interference shielding, and catalytic systems are surveyed. In contrast to reviews organized by specific metals or individual applications, this review emphasizes transferable structural descriptors and cross-system performance trade-offs. Future progress will require standardized reporting, data-enabled structure-property mapping, scalable processing, and reliability-oriented design under realistic operating conditions.