Nylon 11/ethylene-vinyl alcohol/dicumyl peroxide (DCP) blends were prepared using a single-screw extruder. The melting behavior and isothermal crystallization kinetics were investigated using differential scanning calorimetry. The reorganization of nylon 11 crystals is strongly hindered owing to cocrosslinking phenomena. The analysis of the crystallization kinetics demonstrated that the Avrami equation well described the isothermal crystallization process of the primary stage. The spherulites growth kinetics parameters and fold surface free energy were also evaluated. The experimental results confirmed that the presence of DCP increased the crystallization rate. POLYM. ENG. SCI., 48:2354-2361, 2008. (C) 2008 Society of Plastics Engineers