Correlation between non‐isothermal crystallization kinetics and morphology in poly(ε‐caprolactone)/poly(styrene‐co‐acrylonitrile) blends considering the blend phase behavior: Effects of poly(ε‐caprolactone) molecular weight

Abstract

Non‐isothermal crystallization of poly(ε‐caprolactone) (PCL) in semi‐crystalline/amorphous PCL/poly(styrene‐co‐acrylonitrile) (SAN) blends with lower‐critical solution temperature (LCST) phase behavior at temperatures higher than the beginning of PCL crystallization has been studied and quantitatively modeled using different kinetics models. Near‐ and off‐critical PCL/SAN blends were prepared by using two different PCL molecular weights. The kinetics model results verified that the samples containing PCL with higher molecular weight have lower crystallinity and faster crystallization behavior, while adding amorphous SAN chains to PCL retards the crystallization process. A lower crystallization activation energy was relatively required for higher molecular weight, PCL‐2, in off‐critical PCL/SAN blends. However, the easier crystallization with higher degree of crystallinity was attained in near‐critical P80S20 blend containing PCL with lower molecular weight, indicating a shift of the LCST phase diagram of the PCL/SAN blend to higher temperatures by increasing the PCL molecular weight.