Direct Evidence of Graphene‐Induced Molecular Reorientation in Polymer Films

Abstract For the first time, direct evidence of graphene‐induced molecular reorientation in polymer films using polarization modulated infrared reflection absorption spectroscopy (PM‐IRRAS) is presented. By creating favorable electrostatic interactions, graphene–polymer interfaces can be controlled by varying polymer and solvent composition. After transfer of unmodified graphene from copper onto a polymer substrate, polymer chain rearrangement relative to the orientation at the polymer‐copper interfaces is observed using PM‐IRRAS. Transfer success is characterized using both optical transmission measurements and Raman spectroscopy to quantify the transfer fidelity, that is, graphene coverage fraction. Taken together, oxygen‐containing poly(ethylene‐co‐vinyl acetate) shows more polymer chain rearrangement and better graphene coverage compared to oxygen‐free polyethylene. Polymer composition seems to dominate graphene–polymer interactions while solvent choice has a smaller effect on transfer quality. These results are the first direct measurement of this effect and point toward the possibility of engineering graphene–polymer interactions for specific applications.