https://cyberleninka.org/article/n/768408.pdf

Mechanical properties of graphene and graphene-based nanocomposites

The mechanics of graphene nanocomposites: A review

Review of thermal conductivity in composites: Mechanisms, parameters and theory

Grafting of epoxy chains onto graphene oxide for epoxy composites with improved mechanical and thermal properties

In this experimental study, the reinforcing effects of graphene oxide (GO) on portland cement paste are investigated. It is discovered that the introduction of 0.03% by weight GO sheets into the cement paste can increase the compressive strength and tensile strength of the cement composite by more than 40% due to the reduction of the pore structure of the cement paste. Moreover, the inclusion of the GO sheets enhances the degree of hydration of the cement paste. However, the workability of the GO-cement composite becomes somewhat reduced. The overall results indicate that GO could be a promising nanofillers for reinforcing the engineering properties of portland cement paste.

Reinforcing effects of graphene oxide on portland cement paste

Epoxy systems have proven popular having important applications in aerospace and wind energy, but fracture and fatigue resistance of this polymer remain less than desired. Graphene oxide, a form of atomically thin carbon, possessing impressive multifunctional properties and an ideal interface for interacting with polymer matrices, has emerged as a viable reinforcement candidate. In this work, we report enhancements of 28–111% in mode I fracture toughness and up to 1580% in uniaxial tensile fatigue life through the addition of small amounts (≤1 wt %) of graphene oxide to an epoxy system. Graphene oxide was uniquely synthesized by unraveling and splaying open helical-ribbon carbon nanofibers. The resulting oxygenated basal planes and edges of the graphene oxide sheets were observed to promote onset of the cross-linking reaction and led to an increase in total heat of reaction effecting slightly higher glass transition temperatures of the cured composites. Measured improvements were also detected in quasi-st...

Impressive Fatigue Life and Fracture Toughness Improvements in Graphene Oxide/Epoxy Composites

Carbon nanofibers enhance the fracture toughness and fatigue performance of a structural epoxy system

Fracture toughness and creep performance of PMMA composites containing micro and nanosized carbon filaments

Susceptibility to matrix driven failure is one of the major weaknesses of continuous-fiber composites. In this study, helical-ribbon carbon nanofibers (CNF) were dispersed in the matrix phase of a continuous carbon fiber-reinforced composite. Along with an unreinforced control, the resulting hierarchical composites were tested to failure in several modes of quasi-static testing designed to assess matrix-dominated mechanical properties and fracture characteristics. Results indicated CNF addition offered simultaneous increases in tensile stiffness, strength and toughness while also enhancing both compressive and flexural strengths. Short-beam strength testing resulted in no apparent improvement while the fracture energy required for the onset of mode I interlaminar delamination was enhanced by 35%. Extrinsic toughening mechanisms, e.g., intralaminar fiber bridging and trans-ply cracking, significantly affected steady-state crack propagation values. Scanning electron microscopy of delaminated fracture surfaces revealed improved primary fiber–matrix adhesion and indications of CNF-induced matrix toughening.

Daniel R. Bortz

Papers

Impressive Fatigue Life and Fracture Toughness Improvements in Graphene Oxide/Epoxy Composites

Carbon nanofibers enhance the fracture toughness and fatigue performance of a structural epoxy system

Fracture toughness and creep performance of PMMA composites containing micro and nanosized carbon filaments

Mechanical characterization of hierarchical carbon fiber/nanofiber composite laminates

Augmented fatigue performance and constant life diagrams of hierarchical carbon fiber/nanofiber epoxy composites