title: Failure processes in embedded monolayer graphene under axial compression.
abstract: Exfoliated monolayer graphene flakes were embedded in a polymer matrix and loaded under axial compression. By monitoring the shifts of the 2D Raman phonons of rectangular flakes of various sizes under load, the critical strain to failure was determined. Prior to loading care was taken for the examined area of the flake to be free of residual stresses. The critical strain values for first failure were found to be independent of flake size at a mean value of -0.60% corresponding to a yield stress up to -6 GPa. By combining Euler mechanics with a Winkler approach, we show that unlike buckling in air, the presence of the polymer constraint results in graphene buckling at a fixed value of strain with an estimated wrinkle wavelength of the order of 1-2 nm. These results were compared with DFT computations performed on analogue coronene/PMMA oligomers and a reasonable agreement was obtained.
authors.affiliation: 1] Department of Materials Science, University of Patras, Rio Patras, 26504 (Greece) [2] Institute of Chemical Engineering Sciences, Foundation of Research and Technology-Hellas (FORTH/ICE-HT), Stadiou Street, Platani, Patras Acahaias, 26504 (Greece).
authors.forename: Charalampos
authors.initials: C
authors.lastname: Androulidakis
authors.affiliation: Institute of Chemical Engineering Sciences, Foundation of Research and Technology-Hellas (FORTH/ICE-HT), Stadiou Street, Platani, Patras Acahaias, 26504 (Greece).
authors.forename: Emmanuel N
authors.initials: EN
authors.lastname: Koukaras
authors.affiliation: J. Heyrovsky Institute of Physical Chemistry, v.v.i., Academy of Sciences of the Czech Republic, 182 23 Prague 8, Czech Republic.
authors.forename: Otakar
authors.initials: O
authors.lastname: Frank
authors.affiliation: 1] Institute of Chemical Engineering Sciences, Foundation of Research and Technology-Hellas (FORTH/ICE-HT), Stadiou Street, Platani, Patras Acahaias, 26504 (Greece) [2] Inter-departmental Program in Polymer Science & Technology, University of Patras, Rio Patras, 26504 (Greece).
authors.forename: Georgia
authors.initials: G
authors.lastname: Tsoukleri
authors.affiliation: Institute of Chemical Engineering Sciences, Foundation of Research and Technology-Hellas (FORTH/ICE-HT), Stadiou Street, Platani, Patras Acahaias, 26504 (Greece).
authors.forename: Dimitris
authors.initials: D
authors.lastname: Sfyris
authors.affiliation: 1] Institute of Chemical Engineering Sciences, Foundation of Research and Technology-Hellas (FORTH/ICE-HT), Stadiou Street, Platani, Patras Acahaias, 26504 (Greece) [2] Inter-departmental Program in Polymer Science & Technology, University of Patras, Rio Patras, 26504 (Greece).
authors.forename: John
authors.initials: J
authors.lastname: Parthenios
authors.affiliation: 1] Laboratory of Bio-Inspired & Graphene Nanomechanics, Department of Civil, Environmental and Mechanical Engineering, Università di Trento, via Mesiano, 77, I-38123 Trento, Italy [2] Center for Materials and Microsystems, Fondazione Bruno Kessler, Via Sommarive 18, 38123 Povo (Trento), Italy [3] School of Engineering & Materials Science, Queen Mary University of London, Mile End Road, London E1 4NS, UK.
authors.forename: Nicola
authors.initials: N
authors.lastname: Pugno
authors.affiliation: 1] Department of Materials Science, University of Patras, Rio Patras, 26504 (Greece) [2] Institute of Chemical Engineering Sciences, Foundation of Research and Technology-Hellas (FORTH/ICE-HT), Stadiou Street, Platani, Patras Acahaias, 26504 (Greece).
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Papagelis
authors.affiliation: School of Physics and Astronomy, University of Manchester, Manchester, U.K.
authors.forename: Kostya S
authors.initials: KS
authors.lastname: Novoselov
authors.affiliation: 1] Department of Materials Science, University of Patras, Rio Patras, 26504 (Greece) [2] Institute of Chemical Engineering Sciences, Foundation of Research and Technology-Hellas (FORTH/ICE-HT), Stadiou Street, Platani, Patras Acahaias, 26504 (Greece) [3] Inter-departmental Program in Polymer Science & Technology, University of Patras, Rio Patras, 26504 (Greece).
authors.forename: Costas
authors.initials: C
authors.lastname: Galiotis