Graphene is a new nanomaterial with strict two-dimensional layers structure. With excellent mechanical, high electrical and thermal properties, graphene is the ideal filler for polymer-based nanocomposites. Graphene/polymer nanocomposites greatly draw researchers’ attentions in recent years. In this review, we presented and discussed the current development of graphene/polymer nanocomposites. After introducing various methods to synthesize graphene, covalent and noncovalent functionalization of graphene are briefly summarized. Particular emphasis is placed on general methods used to fabricate graphene/polymer nanocomposites and mechanical, electrical, thermal, and gas barrier properties of graphene/polymer nanocomposites. Finally, the challenge of this research area was summarized and its future outlook was prospected.

Contents
1 Introduction
2 Synthesis methods and surface modification of graphene
2.1 Synthesis methods of grapheme
2.2 Surface modification of graphene
3 Graphene-based polymer nanocomposites
3.1 Fabrication approaches to graphene-based polymer nanocomposites
3.2 Properties of graphene-based polymer nano-composites
4 Conclusions and application outlook