title: Uniaxial Drawing of Graphene-PVA Nanocomposites: Improvement in Mechanical Characteristics via Strain-Induced Exfoliation of Graphene.
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.
authors: School of Chemical and Materials Engineering, National University of Sciences and Technology, H-12 Campus, Islamabad, Pakistan. rahimjan@scme.nust.edu.pk.
authors: Rahim
authors: R
authors: Jan
authors: School of Chemical and Materials Engineering, National University of Sciences and Technology, H-12 Campus, Islamabad, Pakistan.
authors: Amir
authors: A
authors: Habib
authors: School of Chemical and Materials Engineering, National University of Sciences and Technology, H-12 Campus, Islamabad, Pakistan.
authors: Muhammad Aftab
authors: MA
authors: Akram
authors: School of Chemical and Materials Engineering, National University of Sciences and Technology, H-12 Campus, Islamabad, Pakistan.
authors: Tanveer-Ul-Haq
authors: TU
authors: Zia
authors: School of Chemical and Materials Engineering, National University of Sciences and Technology, H-12 Campus, Islamabad, Pakistan.
authors: Ahmad Nawaz
authors: AN
authors: Khan
keywords: Graphene; Liquid phase exfoliation; Nanocomposites; Polymer grafting; Strain-induced exfoliation