Effect of a chain extender on the crystallization behavior of nylon 66

Abstract The crystallization behaviors and crystalline morphologies of initial and chain‐extended nylon 66 samples were studied with differential scanning calorimetry and polarizing microscopy, respectively. The crystallization rate increased and the size of the spherulites decreased with chain‐extension. In addition, a two‐peak behavior was observed in chain‐extended nylon 66. These results showed that for the chain‐extended nylon 66, there was heterogeneous nucleation during crystallization. Therefore, the chain extender possibly functioned as a nucleating agent at the same time. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 68–71, 2004