Abstract
Civil engineering infrastructure suffers material degradation, shortened service life and high maintenance costs under harsh environments and natural aging, threatening public safety. Nanopolymer composites, featuring designable microstructures and excellent macroscopic properties, provide a revolutionary solution to improve the weather resistance and toughness of civil engineering materials. This paper systematically clarifies the modification mechanisms of nanocomposites, focusing on nanofiller-polymer matrix interfacial interactions (physical adsorption, chemical bonding) and their synergistic effects in enhancing environmental aging resistance (UV, corrosion, freeze-thaw) and mechanical performance (toughening, strengthening, dynamic load resistance). It summarizes the latest applications in nanomodified protective coatings, sealing/bonding materials and composite structural components, revealing the inherent "structure-property-application" relationships. Furthermore, this paper addresses core large-scale application challenges, including technical bottlenecks, performance evaluation limitations and economic/environmental barriers. Finally, future research directions are proposed, covering multifunctional intelligent materials, green development, interdisciplinary computational methods and standardized systems. This review offers an integrated perspective, providing theoretical guidance and practical references for advancing durable, resilient and sustainable civil engineering.