Glycidyl methacrylate (GMA) functionalized. acrylonitrile-butadiene-styrene (ABS) copolymers have been prepared via an emulsion polymerization process. The epoxy-functionalized ABS (e-ABS) particles were used to toughen nylon-6. Molau tests and FTIR results showed the reactions between nylon-6 and e-ABS have taken place. Scanning electron microscopy (SEM) displayed the compatibilization reaction between epoxy groups of e-ABS and nylon-6 chain ends (amine or carboxyl groups), which improve disperse morphology of e-ABS in the nylon-6 matrix. The presence of only a small amount of GMA (1 wt %) within the e-ABS copolymer was sufficient to induce a pronounced improvement of the impact strength of nylon-6 blends; whereas further increase of the GMA contents in e-ABS resulted in lower impact strength because of the crosslinking reaction between nylon-6 and e-ABS, resulting in agglomeration of the ABS particles. SEM results showed shear yielding of the nylon-6 matrix and cavitation of rubber particles were the major toughening mechanisms. (c) 2005 Wiley Periodicals, Inc.