A novel composite was prepared by ball-milling crystalline cellulose and maleic anhydride (MA) grafted polypropylene (MAPP) and its characteristics compared with a corresponding composite prepared by a conventional melt-mixing method. The ball-milling induces the formation of more ester bonds between cellulose and MAPP. The resulting MAPP chains bound to particles of cellulose, which created much stronger interfacial adhesion between the cellulose particles and the MAPP matrix. Accordingly, such enhanced interfacial adhesion substantially differentiates the mechanochemically prepared composite from the melt-mixed composite. (C) 2004 Wiley Periodicals, Inc.