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Mechanical properties of graphene, e.g., strength, modulus, and fracture toughness are extremely sensitive to flaws. Here the fracture properties of stacked bilayer graphene sheets (SBLG) are reported, obtained via stacking two individually grown graphene sheets. The SBLG is presented here as a building block for flaw‐resilient nanomaterials. The fracture properties of freestanding SBLG sheets, suspended on transmission electron microscope (TEM) grids, are characterized by stretching the TEM grid inside an scanning electron microscope (SEM) chamber and monitoring the local displacements in real‐time. The fracture toughness is measured and expressed as a function of the critical displacement required to propagate existing cracks in the experiment via computational models. This approach decouples force and displacements measurements, and utilizes the known elastic modulus along with the known displacement boundary conditions at the onset of crack growth to estimate the far field force and stress. This strategy represents a breakthrough in nanoscale fracture mechanics for statistical analysis and high throughput experimens on multiple samples at a time. Results demonstrate that the SBLG is markedly tougher than as‐grown single or multilayer graphene, with a mode I fracture toughness of ≈28.06 ± 7.5 MPa. The mechanisms leading to a higher toughness of SBLG are also analyzed and discussed.

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Determination of the reliability and durability of polymers in structural applications is highly dependent on the resistance to time-dependent plastic deformation. In this study, creep behaviour and enhancement in creep resistance of polystyrene-graphene nanocomposites is investigated at low filler loading. Herein, 2D material (graphene) is synthesised by the liquid-phase exfoliation method ( LPE) using the tetrahydrofuran ( THF) solvent via batch sonication. Samples are characterised by Scanning Electron Microscopy ( SEM) for morphology analysis and X-rays Diffraction ( XRD) for identification of polystyrene-graphene (PS-G) peaks in nanocomposites. Additionally, Atomic Force Microscopy ( AFM) is employed to quantify sheet’s thickness and Optical Microscopy ( OM) to corroborate the dispersion of 2D sheets. The creep resistance of PS-G nanocomposites is measured at room temperature (25°C) by incorporating 2D sheets of flake length ∼359 μm with 0.1, 0.3, 0.5, 0.7 and 0.9 wt.%. A significant enhancement in the time to withstand constant creep load (1 N) is observed. The creep resistance of the samples exhibits a maximum increase of 79%, 258.24%, 647.25%, 417.58% and 760.44%, respectively, compared to pristine polystyrene. This increase in creep resistance resulted from intense interfacial contact between polymer chains and filler accompanied by adequate scattering/dispersion in the polymer matrix.