Preparation Of Graphene Based Nanocomposites In Electrospun Polyaniline/Polyethylene Oxide Blends

Electrospinning is a convenient method to produce polymer nanofibers with controlled diameters from tens of nanometers to micrometers. The resulting non-woven fiber mats have high specific surface areas in the range of 1-100 m²/g. Combining these properties with the high electrical conductivity of intrinsically conductive polymers, conductive electrospun fiber mats are promising for a variety of applications such as electronic, biomedical, sensor and optical fields.

Polyaniline is one of the most studied electrically conductive polymers and it is unique due to its ease of synthesis, environmental stability, and simple doping/dedoping chemistry. It is however relatively difficult to process compared to most other polymers. As is common among intrinsically conductive polymers, it has a fairly rigid backbone due to its high aromaticity. Thus, the elasticity of its solutions is generally insufficient for it to be electrospun directly into fibers. Moreover, polyaniline has poor solubility in common solvents, which further complicates it electrospinnability. To circumvent these problems, it is possible to electrospun polyaniline by blending it with an easily electrospinnable polymer such as polyethylene oxide. However, the presence of an insulator copolymer decreases the fibers conductivity due to dilution of the conducting component. A good strategy for improving the electrical properties of this electrospun fibers blend is to incorporate carbon-based conductive nanofillers into the nanofibers.

Since the discovery of graphene in 2004, it has attracted tremendous research interest. In recent years, graphene nanosheets have been recognized as a promising, cost effective and high quality alternative to carbon nanotubes in composite applications. Graphene is a single-atom-thick, two-dimensional sheet of sp²-hybrized carbon atoms arranged in a honeycomb crystal structure with exceptionally high strength, surface area, thermal conductivity, and unique electronic conductivity. Therefore, considering the excellent properties of graphene and polyaniline, a highly conductive polyaniline/polyethylene oxide composite with graphene as nanofillers may be obtained.

In this work, we report the preparation of electrospun polyaniline/polyethylene oxide nanofibers fibers filled with non-covalently functionalized graphene sheets. These graphene/polymer nanofibers have the potential to serve in a variety of applications, including conductive wires and sensors.