Polydispersity of ethylene sequence length in metallocene ethylene/α‐olefin copolymers. II. Influence on crystallization and melting behavior
作者： Fajun Zhang , Jieping Liu , Fengchao Xie , Qiang Fu , Tianbai He
DOI: 10.1002/POLB.10146
关键词:
摘要: In this work, crystallization and melting behavior of metallocene ethylene/alpha-olefin copolymers were investigated by differential scanning calorimetry (DSC) atomic force microscopy (AFM). The results indicated that the temperatures for all samples directly related to long ethylene sequences instead average sequence length (ASL), whereas enthalpy crystallinity ASL, is, both parameters decreased with a decreasing ASL. Multiple peaks analyzed thermal analysis. Three phenomena contributed multiple behaviors after isothermal crystallization, crystals formed during quenching, melting-recrystallization process, coexistence different crystal morphologies. Two types morphologies could coexist in having high comonomer content crystallization. They chain-folded lamellae bundlelike short sequences. phenomenon was further proved AFM morphological observation.
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