Chia-Yu LiaoChih-Jung LinYU-JANE SHENGHeng-Kwong Tsao2025-04-152025-04-152025-03-15https://www.scopus.com/record/display.uri?eid=2-s2.0-85217962157&origin=recordpagehttps://scholars.lib.ntu.edu.tw/handle/123456789/728116While stretching hydrogel nanofilms enables the acquisition of stress–strain curves, deciphering the internal structure and mechanisms through experiments remains challenging. In this work, dissipative particle dynamics simulations are employed to observe microstructural changes in elongated hydrogel nanofilms. The morphological changes of the film, up to the point of fracture, are observed, and the corresponding stress–strain curve is obtained. Microscopic characteristics, including polymer size, strand size, and bond length, are systematically analyzed to understand the network's deformation. Additionally, the breakages of polymers, strands, and bonds are closely monitored. In a thin film, the microstructure of the interfacial region differs from that of the bulk region, with the latter enduring more forces during extension. Consequently, as film thickness increases, the contribution from the bulk region becomes more pronounced, leading to a further enhancement of mechanical properties.Film thickness effectHydrogelMechanical propertiesMicrostructural dynamicsNanofilm[SDGs]SDG11journal article10.1016/j.molliq.2025.127172