Functionalization of carbon nanotubes (CN) with polymers have been widely studied however, CN functionalized with polymers are not available yet at industrial scale and are very expensive. On the other hand, Graphite Oxide (GO) under high both temperature and pressure leads to obtain Expanded Graphite (EG). GO is cheaper, available at large scale, and their expansion and functionalization, arises as a alternative to the CN.In this work, a novel route to obtain EG and functionalized at the same time, using nitroxide groups is presented. Commercial natural graphite NG was expanded in the presence of solvent, nitroxides or initiator using one synthetic pathway. It is proposed that the defects in the surface of the platelets (double bonds) allow the abstraction of hydrogen atoms forming a radical centered in carbon which is trapped by the nitroxide, carrying out the functionalization of NG. EG and NG were characterized in detail by XRD and SEM. The results suggest that the NG was expanded around 20% by the covalent bonding of nitroxide groups to the platelets, which helps to the separation of graphite layers. The work proposed here has several advantages over the previous methods, including a high efficiency of expansion process, the use of a non-toxic intercalant, and the capability for mass production of expanded graphite for industrial applications