A novel polymer-grafted C-60 fullerene having both hydrophilic poly(ethylene oxide) (PEO)and hydrophobic polystyrene (polySt) chains, Was Successfully synthesized by postpolymerization of St initiated by PEO-grafted C-60 fullerene, bis-adduct C-60-(PEO)(2), having peroxyester (POE) groups. C-60-(PEO)(2) was prepared by the reaction of C-60 fullerene with PEO-azopolymer. The introduction of POE groups onto C-60-(PEO)(2) was achieved by trapping of POE radicals formed by the thermal decomposition of 1,1 -bis(t-butyldioxy)cyclohexane (BDOC) The structure of C-60-(PEO)(2)(POE) was confirmed by FT-IR, UV-vis, and DSC. The postgraft radical polymerization of St was successfully initiated by the POE groups of C-60-(PEO)(2)(POE) to give polySt-grafted C-60-(PEO)(2) The structure of polySt-grafted C-60-(PEO)(2) was identified by FT-IR, SEC, and thermal decomposition gas chromatograms and mass spectra (GC-MS). The polySt-grafted C-60-(PEO)(2) was soluble in good solvents for polySt and PEO, but insoluble in n-hexame which is poor solvent for polySt and PEO, and partially Soluble in water which is good solvent for PEO but poor solvent for polySt. The compatibility of polySt-grafted C-60-(PEO)(2) in polySt matrix was remarkably improved in comparison with that of C-60-(PEO)(2). In addition, thermal stability of polySt-grafted C-60-(PEO)(2) increased in comparison with that of polySt and PEO. (C) 2009 Elsevier, B.V. All rights reserved.