New paper in ACS Omega: Graphene Quantum Dots Infusion to Create Stronger, Tougher, and Brighter Polymer Composites

Navathej Gobia, Darshan Vijayakumar a, Ozgur Keles a and Folarin Erogbogbo a*

http://pubs.acs.org/doi/full/10.1021/acsomega.6b00517

ABSTRACT: Incorporation of nanoparticles into polymer resins has recently attracted a significant amount of attention from researchers for the nanoparticles ability to alter the properties of the resin. While graphene-based structures possess a 2D honeycomb arrangement of carbon atoms that make them desirable for engineering composite materials, quantum dots formulations have been primarily been used in optoelectronic applications that take advantage of quantum confinement and size tunable properties. Graphene and quantum dots (GQDs) are ubiquitous in current research literature, however, the impact of graphene quantum dots on the physical properties of polymer resins like epoxy remains unclear. Here, we show that infusing graphene quantum dots into an epoxy polymer matrix results in: (1) a 2.6 fold increase in toughness of the polymer resins; (2) 2.25 increase in the tensile strength of the polymer resins compared to its original tensile strength; (3) uniform loading at weight percentages as high as 10% of the polymer resin, (4) an 18% change to max % increase in tensile strain compared to neat polymer resin without GQDs even though there is an increase in tensile strength; (5) a 2.5 times increase in Young’s modulus compared to the neat polymer resin, all while maintaining excellent optical properties of the composite formulation. Our results demonstrate that graphene quantum dots with dual acid and alcohol functional groups can enable high loading percentages, which, in turn, gives rise to composite materials that are simultaneously stronger and tougher. We believe these graphene quantum dots – created from an abundant source – to be a starting point for new and more sophisticated composite materials with potential in mechanical, electrical, and photosensitive applications.

Posted 3rd April 2017 by Ozgur Keles