Abstract
Interfacial adhesion has been identified as being key for realizing flexible devices. Here, strong interfacial nanoconnections involving metallic patterns on polymer surfaces were fabricated via a molecular bonding approach, which includes UV-assisted grafting and molecular self-assembly. The interfacial characteristics of conductive patterns on liquid crystal polymer substrates were observed via transmission electron microscopy and atomic force microscopy infrared spectroscopy. The interfacial molecular layers have a thickness of 10 nm. Due to the successful molecular bonding modifications, interfacial adhesion has been sufficiently improved; in particular, the peel-related breakage sites will be located in the modified layers on the plastic surface beneath the interface after the metallic coatings are peeled off. Integrating X-ray photoelectron spectroscopy, infrared spectroscopy, and scanning electron microscopy results, the molecular bonding mechanism has been revealed: UV-assisted grafting and self-assembly result in the construction of interfacial molecular architectures, which provide nanosized connecting bridges between the metallic patterns and polymer surfaces. Such in-depth interfacial studies can offer insight into interfacial adhesion, which will impact on the development of metal/polymer composite systems and continue to push the improvement of flexible devices.