Fabrication and Characterization of Graphene Oxide/Thermoplastic Composites Prepared by In-situ Interfacial Polymerization

Abstract

Today, graphene oxide (GO)/thermoplastic composites have been researched actively to improve the interfacial properties between polymer and GO. In these nanocomposites, dispersion of GO in polymer matrix and the interfacial bonding between GO and polymer are key factors that govern the interfacial properties. Accordingly, polymer has been grafted onto GO by various chemical reactions. Furthermore, modification of GO surface can enhance the dispersion and interfacial properties through attachment of specific functional groups on GO. In this study, GO was functionalized with thionyl chloride (SOCl2) to enhance interaction between matrix and GO. The acyl chloride-functionalized GO (AGO) was used as the reinforcement in the nanocomposites. AGO/Nylon 6,6 composites were fabricated using interfacial polymerization of Nylon 6,6, which involves synthesis of AGO/Nylon 6,6 interphase at the interface between organic and aqueous phases. Furthermore, CNTs were dispersed into AGO solution resulting in Nylon 6,6 composites containing hybrid fillers, such as AGO and CNT. The morphology and chemical state of AGO were analyzed using TEM, SEM, XRD, Raman and FT-IR. Meanwhile, the CNT-based Nylon 6,6 composites showed higher peak intensity of amide 1 than that of AGO-based composites, which was indicative of the activated formation of hydrogen bonding. In terms of crystallinity, AGO-based composites were more effective than CNT-based composites due to the graphene sheets serving as strong nucleating agents and their large surface area where the Nylon 6,6 chains need more time to adjust their conformation.