This paper deals with the synthesis and characterization of poly(ethylene glycol)-grafted expanded graphite (PEG-grafted EG) as a novel composite material. The PEG-grafted EG composite was prepared by grafting PEG in the EG layers using isophorone diisocyanate (IPDI) as coupling agent. The EG was prepared after microwave irradiation treatment from the expandable graphite, the obtained EG modified by an excess amount of IPDI. Modified expanded graphite (MEG) mixed in anhydrous N,N-dimethylformamide (DMF) and grafted PEG at low temperature atmosphere. The samples of EG and PEG-grafted EG composite was characterized by using scanning electron microscopy (SEM), infrared spectroscopy (IR) and thermogravimetric (TG) analysis technique.