Graphene coated substrates and resulting composites
The deposition of graphene is accomplished by various techniques that result in a change of the graphene's solubility in the liquid medium. The solubility change enables the deposition of the graphene onto the substrate. Once the graphene is deposited onto the substrate, the at least partially coated substrate may be separated from the liquid medium. The substrates may then serve as a carrier to deliver the graphene to a desired application.
1. A method of coating graphene onto a substrate, the method comprising transferring solubilized graphene onto the substrate in a liquid medium by changing the solubility of graphene in the liquid medium wherein changing the solubility of the graphene in the liquid medium occurs by adding an antisolvent, cooling of the liquid medium, bubbling a vapor through the liquid medium, adding a salt to the liquid medium, changing the liquid medium's pH value, introducing shear into the liquid medium, distilling the liquid medium, flowing the liquid medium through a packed column, evaporating solvent, changing a surface energy of the substrate, or combinations thereof.
2. The method according to claim 1 , further comprising separating the substrate coated with the graphene from the liquid medium.
3. A method of forming a polymeric composite, the method comprising melt processing a polymeric matrix with a substrate having at least a portion of a surface of the substrate coated with graphene released from the substrate with a solvent during or before melt processing to form the polymeric composite wherein the graphene, the substrate or both are subject to surface modification in a liquid medium wherein the surface modification is accomplished by introducing amines, aminoazines, titanates, silanes, or combinations thereof into the liquid medium.
4. The method according to claim 3 , wherein the substrate comprises a plurality of particles, spheres, fibers, or combinations thereof.
5. The method according to claim 3 , wherein the substrate melts or forms a vapor component during melt processing.
6. The method according to claim 3 , wherein the substrate releases the graphene into the polymeric matrix during melt processing.