Crystal growth rates and master curves of poly(ethylene succinate) and its copolyesters using a nonisothermal method

Abstract

AbstractThe spherulitic growth of poly(ethylene succinate) (PES) and two PES‐rich copolyesters at constant cooling rate was monitored and recorded using a system of polarized light microscope. Individual experiment of these polyesters lasted 40, 60, and 120 min, respectively. A continuous curve of isothermal growth rates between the melting and glass transition temperatures can be obtained after curve fitting procedures. These curves fit very well with those data points determined in the isothermal experiments, which are time consuming. The continuous data of PES was analyzed with the Hoffman (Lauritzen equation. A transition of regime II → III was found at 70.7 °C, which is very close to the literature values. The maximum growth rate was formulated in the Arrhenius and WLF expressions for the molecular transport term. A master curve of crystal growth rate for PES was constructed based on the continuous data of PES. When the reduced growth rates after normalization were plotted against the reduced temperatures, a universal master curve was observed for PES and two PES‐rich copolyesters. This nonisothermal method provides an efficient and reliable way for studying the crystallization kinetics of polymer and for constructing a universal master curve of crystal growth rate of PES. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 932–939, 2010