Ionic liquid‐modified graphene/poly(vinyl alcohol) composite with enhanced properties

Abstract

How to preserve the structure integrity of graphene while enhance its dispersion and compatibility in matrix attracts the attention of researchers in graphene/polymer nanocomposite field. In this paper, methacryloxyethyltrimethyl ammonium chloride (DMC), a kind of ionic liquids, was first used to non‐covalently functionalize graphene in the process of graphene oxide (GO) reduction. The as‐modified graphene (DMC‐rGO) was further incorporated into poly(vinyl alcohol) (PVA) matrix by solution casting technique to fabricate DMC‐rGO/PVA composites. The structure and properties of the obtained DMC‐rGO were investigated by X‐ray diffraction analysis (XRD), X‐ray Photoelectron Spectroscopy (XPS), Transmission Electron Microscope (TEM), Atomic force microscopy (AFM), and Raman test. The results showed that graphene could be successfully modified by DMC through ionic–π interaction and the structure integrity of the graphene could be reserved by this non‐covalently approach. Furthermore, after co‐reduction process, some hydroxyl groups were introduced into DMC‐rGO. In virtue of these intrinsic properties of DMC‐rGO, the fabricated DMC‐rGO/PVA composites exhibit considerable enhancements in mechanical properties and remarkable improvements in thermal stability, as well as the enhancement in electrical conductivity at low DMC‐rGO loading. This simple modification approach gives a new opportunity to improve the performances of graphene/polymer composites. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45006.

Cation–π Interactions in Graphene‐Containing Systems for Water Treatment and Beyond

“…[ 134 ] Similar results were obtained by incorporating ionic liquid modified graphene into poly(vinyl alcohol) (PVA) by solution casting technique. [ 135 ] Using this coupling agent, the structure integrity of graphene could be preserved and the aggregation was relieved. With a low loading amount of 2 wt%, marked enhancements in mechanical properties, thermal stabilities and electrical conductivities were achieved.…”

Using an Ionic Liquid to Reduce the Electrical Percolation Threshold in Biobased Thermoplastic Polyurethane/Graphene Nanocomposites

“…ILs are known to interact with the graphene by cation–π stacking and π–π interactions which prevent reaggregation of graphene sheets [9,10]. Their ability to improve the dispersion of graphene in several thermoplastic matrices has been demonstrated [7,9,11,12,13,14]. Therefore, it can be concluded that, although not clearly detected by TEM, the modification of GR with IL leads to the enhanced dispersion of the nanofiller, which, in turn, gives rise to a significantly lower electrical percolation threshold in the bTPU/GR-IL NCs than in the bTPU/GR NCs.…”

“…ILs are believed to interact with graphene by cation–π stacking and π–π interactions which prevent the reaggregation of graphene sheets while preserving the electronic structure of the graphene and its intrinsic properties [9,10]. As a result, ILs have been successfully used as dispersing agents for graphene in several thermoplastic matrices, including poly(vinyl alcohol) [11], a copolyamide [12], polylactide [9], polystyrene [13], poly(methyl methacrylate) [14], and polyvinylidene fluoride [7].…”

Influence of lithium salt-induced phase separation on thermal behaviors of poly(vinylidene fluoride)/ionic liquid gels and pore/void formation by competition with crystallization

“…The combination of ILs with polymers is expected to further extend their applicability. Novel functions [4][5][6][7] and physical properties [8][9][10][11][12][13][14] are reported in polymer/IL systems. For example, polymer gels swollen by ILs are excellent gel polymer electrolytes (GPEs) with the properties of ILs, which includes great electrochemical stability across a large window.…”