Polymer-stabilized graphene dispersions at high concentrations in organic solvents for nanocomposite production

Ahmed S. Wajid; Sriya Das; Fahmida Irin; H. S. Tanvir Ahmed; John L. Shelburne; Dorsa Parviz; Robert J. Fullerton; Alan F. Jankowski; Ronald C. Hedden; Micah J. Green

arXiv · 1107.1519

Polymer-stabilized graphene dispersions at high concentrations in organic solvents for nanocomposite production

Ahmed S. Wajid·Sriya Das·Fahmida Irin·H. S. Tanvir Ahmed·John L. Shelburne·Dorsa Parviz·Robert J. Fullerton·Alan F. Jankowski·Ronald C. Hedden·Micah J. Green

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Abstract

We demonstrate a simple and effective technique for dispersing pristine (unfunctionalized) graphene at high concentrations in a wide range of organic solvents by use of a stabilizing polymer (polyvinylpyrrolidone, PVP). These polymer-stabilized graphene dispersions are shown to be highly stable and readily redispersible even after freeze-drying. This technique yields significantly higher graphene concentrations as compared to prior studies. Excellent enhancement in thermal conductivity of the fluid by addition of pristine graphene is also demonstrated. These well-dispersed pristine graphene sheets were then used as a strong and conductive nano-filler for polymer nanocomposites. PVP/graphene nanocomposites were produced via bulk polymerization of N-vinylpyrrolidone loaded with dispersed graphene, resulting in excellent load transfer and improved mechanical and electrical properties.

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Ahmed S. Wajid, Sriya Das, Fahmida Irin, H. S. Tanvir Ahmed, John L. Shelburne, Dorsa Parviz, Robert J. Fullerton, Alan F. Jankowski, Ronald C. Hedden, Micah J. Green. 2011-07-07. Polymer-stabilized graphene dispersions at high concentrations in organic solvents for nanocomposite production. https://arxiv.org/abs/1107.1519

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