Facile one pot green synthesis of –NH2 surface functionalized graphene-polymer nanocomposite: Subsequent utilization as stabilizer in pickering emulsions

• Published in: Colloids and surfaces. A, Physicochemical and engineering aspects Vol. 641; p. 128594
• Main Authors: Narukulla, Ramesh, Ojha, Umaprasana, Sharma, Tushar
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 20.05.2022
• Subjects: Graphene, Graphene-PAHz nanocomposite; In-situ reduction; One-pot synthesis; PAHz/rGO nanocomposite; Pickering Emulsion; Polyacryloyl hydrazide; Surface functionalization; Surface functionalization; One-pot synthesis; PAHz/rGO nanocomposite; In-situ reduction; Graphene, Graphene-PAHz nanocomposite; Polyacryloyl hydrazide; Pickering Emulsion
• ISSN: 0927-7757; 1873-4359
• DOI: 10.1016/j.colsurfa.2022.128594

Simple and cost-effective synthesis of surface functionalized graphene and its nanocomposites with polymers is strongly desirable to further expand their utility. Most of the methods reported till date use separate procedures to reduce the graphene oxide (GO), functionalize the resulting graphene and subsequently prepare the nanocomposite with polymers respectively. In this report, we are utilizing a one-pot hydrothermal synthetic procedure to prepare polymer-graphene nanocomposite through in-situ reduction of GO and amine functionalization of resulting graphene. Polyacryloyl hydrazide (PAHz) possessing hydrazide functional groups is used as the reducing agent to convert the GO to the graphene, subsequently functionalize the resulting graphene with the amino groups and encapsulates the resulting –NH2 functional graphene to prepare the PAHz/rGO nanocomposite. Various characterization techniques including UV-Vis, fluorescence, XPS, HRTEM and DLS is utilized to characterize the nanocomposite. The resulting nanocomposites possessing hydrodynamic size of ~ 40 nm is utilized to stabilize Pickering emulsion based on olive oil/n-decane and water. The resulting Pickering emulsion exhibited excellent stability with proper droplet packing and no sign of creaming till 17 days under ambient conditions suggesting the efficacy of the PAHz/rGO nanocomposite as stabilizing agent, which is superior compared to a number of systems studied in recent literature. Overall, the synthesized nanocomposites with a narrow size distribution can be potentially utilized in a number of useful areas. [Display omitted] •Polyacryloyl hydrazide is an effective polymeric reductant for GO.•A green route devoid of harsh chemicals and organic solvents to convert GO to rGO is explored.•One-Pot strategy to simultaneously convert GO to rGO and prepare nanocomposite with polymer is accomplished.•The polymer-GO nanocomposites are capable of stabilizing Pickering emulsion at ultra-low loading.