Morphogenesis and Chain Behaviors Related to Crystallization in Ultrathin Polymer Films

As a new and intriguing topic in polymer physics,the crystallization in ultrathin films has received a considerable attention in recent years,and it has provided opportunities for studying polymer crystallization and related chain behaviors in real space and time.The crystallization in ultrathin polymer films depends strongly on film thickness(D),particularly those with D20 nm exhibit a great deviation from bulk crystallization both in crystalline morphology and crystallization kinetics.The accumulated studies mainly focus on the morphology,crystal dimensions,crystal growth rate and habit,crystal melting and crystallinity etc.,involving the influences of temperature,film thickness,chemical property of substrate,and film composition and structure on the crystallization;however,some experimental results and interpretations are not completely consistent with each other,and even contradictory sometimes.In the present paper,the recent activities related to the crystallization in ultrathin polymer films are reviewed and discussed,with emphasis upon the morphogenesis of crystallization and related chain behaviors.