Shish-kebab of polyolefin by melt manipulation strategy in injection-molding: A convenience pathway from fundament to application

[摘要] Due to both theoretical and practical importance, the formation mechanism of shear-induced shish-kebab and the precise microstructure and molecular composition in shish-kebab have been extensively investigated for many years. However, a systematic review on the manipulation of shish-kebab superstructure in the injection-molded specimens, taken account of combining theoretical understanding, preparation processing, structural/morphological control and macroscopic properties, has rarely seen in the open publication by far. In this article, we will discuss mainly the topic of formation of fine polyolefin shish-kebab superstructure facilitated by melt manipulation strategy in injection-molding process. The main body of this review is governed by a logical sequence of (fundamental research)-(injection molding of melt manipulation)-(manipulation of shish-kebab)-(macroscopic mechanical properties). The fundamental understandings of the early stage of shish-kebab crystallization, transition process from random entangled chains network to stable shish-kebab cylindrulite, and the role of long polymer chains on shish-kebab formation, are very helpful for in-depth comprehension of shear-induced shish-kebab in realistic processing. Various highly oriented morphologies with fine shish-kebab superstructure in injection-molded bars of polyolefin melts, including single component polyolefin melt, biphase melts of blend and heterogeneous melts of polyolefin/inorganic filler composites, could be achieved via melt manipulation strategy, as demonstrated by the work mainly from our group. (C) 2008 Elsevier Ltd. All rights reserved.

[发布日期] 2008-10-17

[关键词] Shish-kebab;Melt manipulation;Shearing in injection molding