Functionalization of Graphene Sheets via Chemically Grafting of PMMA Chains Through<i>in-situ</i>Polymerization

Abstract

Abstract In this work, we report the preparation of graphene nanoplatelet which covalently functionalized with PMMA chains by introduction of vinyl groups onto graphene surface through simple esterification reaction between hydroxyl groups of graphite oxide and methacrylic anhydride. The synthesis is followed by in-situ polymerization with MMA monomers. The structural properties were characterized with X-ray diffraction spectroscopy (XRD) and scanning electronic microscopy (SEM) that showed the crystalline graphite is converted to individual layers during the synthesis steps. The grafting of PMMA chains was monitored with IR spectroscopy (FT-IR) and thermogravimetric analysis (TGA). The TGA results revealed 40% wt of PMMA chains chemically grafted onto graphene surface. Significant increase in glass transition temperature (Tg) and existence of polymer chains in two positions (physically absorbed and chemically grafting onto graphite surface) are indicated by differential scanning calorimetric (DSC) analysis. Keywords: Graphitenanographenegraftingmodificationpmma in-situ polymerizationthermal stability Acknowledgments We are thankful to the Research Council of the University of Tehran. The authors gratefully acknowledge the kind assistance from Ms. A. Fotouhi at Polymer & Thermal Analysis Laboratory of the University College of Science, University of Tehran for TGA and DSC analyses. We thank Mr. Hashemi at Laboratory of Electron Microscopy of University College of Science, University of Tehran, for TEM, SEM analyses and helpful discussions.