Poly(etherimide)s (PEIs) with different chemical structures were synthesized and characterized, which were employed to toughen epoxy resins (EP/PEI) and carbon fiber-reinforced epoxy composites (CF/EP/PEI). Experimental results revealed that the introduction of the fluorinated groups and meta linkages could help to improve the melt processability of EP/PEI resins. The EP/PEI resins showed obviously improved mechanical properties including tensile strength of 89.2 MPa, elongation at break of 4.7% and flexural strength of 144.2 MPa, and good thermal properties including glass transition temperature (T-g) of 211 degrees C and initial decomposition temperature (T-d) of 366 degrees C. Moreover, CF/EP/PEI-1 and CF/EP/PEI-4 composites showed significantly improved toughness with impact toughness of 13.8 and 15.5 J/cm(2), respectively. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 119: 3162-3169, 2011