Uniaxial Drawing of Graphene-PVA Nanocomposites: Improvement in Mechanical Characteristics via Strain-Induced Exfoliation of Graphene

Rahim Jan; Amir Habib; Muhammad Aftab Akram; Tanveer-Ul-Haq Zia; Ahmad Nawaz Khan

doi:10.1186/s11671-016-1595-2

Uniaxial Drawing of Graphene-PVA Nanocomposites: Improvement in Mechanical Characteristics via Strain-Induced Exfoliation of Graphene

Nanoscale Res Lett. 2016 Dec;11(1):377. doi: 10.1186/s11671-016-1595-2. Epub 2016 Aug 24.

Authors

Rahim Jan¹, Amir Habib², Muhammad Aftab Akram², Tanveer-Ul-Haq Zia², Ahmad Nawaz Khan²

Affiliations

¹ School of Chemical and Materials Engineering, National University of Sciences and Technology, H-12 Campus, Islamabad, Pakistan. rahimjan@scme.nust.edu.pk.
² School of Chemical and Materials Engineering, National University of Sciences and Technology, H-12 Campus, Islamabad, Pakistan.

Abstract

Polyvinyl alcohol (PVA)-stabilized graphene nanosheets (GNS) of lateral dimension (L) ~1 μm are obtained via liquid phase exfoliation technique to prepare its composites in the PVA matrix. These composites show low levels of reinforcements due to poor alignment of GNS within the matrix as predicted by the modified Halpin-Tsai model. Drawing these composites up to 200 % strain, a significant improvement in mechanical properties is observed. Maximum values for Young's modulus and strength are ~×4 and ~×2 higher respectively than that of neat PVA. Moreover, the rate of increase of the modulus with GNS volume fraction is up to 700 GPa, higher than the values predicted using the Halpin-Tsai theory. However, alignment along with strain-induced de-aggregation of GNS within composites accounts well for the obtained results as confirmed by X-ray diffraction (XRD) characterization.

Keywords: Graphene; Liquid phase exfoliation; Nanocomposites; Polymer grafting; Strain-induced exfoliation.