The crystallization behavior and morphology of poly(ethylene 2,6-naphthalte) (PEN) were investigated by means of differential scanning calorimetry (DSC), polarized optical microscopy (POM) and transmission electron microscopy (TEM). POM results revealed that PEN crystallized at 240 degreesC shows the coexistence of alpha and beta-form spherulite morphology with different growth rates. In particular, when PEN crystallized at 250 degreesC, the morphology of spherulites showed a squeezed peanut shape. The Avrami exponents decreased from 3 to 2.8 above the crystallization temperature of 220 degreesC, indicating a decrease in growth dimension. Analysis from the secondary nucleation theory suggests that PEN crystallized at 240 degreesC has crystals with both regime I and regime II. In TEM observation, the ultra-thin PEN film crystallized at 200 degreesC showed the spherulitic texture with characteristic diffractions of alpha-form, while PEN crystallized at 240 degreesC generated an axialite structure with only beta-form diffraction patterns. In addition, despite a long crystallization time of 24 h, amorphous regions were also observed in the same specimen. It was inferred that the initiation of PEN at 240 degreesC generates only beta-form crystals from axialite structures. (C) 2003 Elsevier Ltd. All rights reserved.