writer:Zhao Baijin; Li Xiangyang; Huang Youju; Cong Yuanhua; Ma Zhe; Shao Chunguang; An Haining; Yan Tinzi; Li Liangbin*
keywords:Stretched Network,Crystallization of Polymer
source:期刊
specific source:Macromolecules 2009, 42, 1428-1432
Issue time:2009年
the nature of hierarchical crystallization of polymer under flow field was studied on two simplified mixtures of short free chains and end-linked network,which were designed to mimic the blend of short and long chains. With a mesh size as the same as the Me, where no disentanglement occurs, the acceleration of nucleation in the stretched mixtures stem from the synergetic effect between the orientation of the network and the fast diffusion of the free chains, which renders the oriented nuclei composing mainly of short free chains. With the occurrence of EDT in the network with large mesh size, the long chains are the main contributor of the oriented nuclei, in agreement with the traditional view. The former may be the general case in polymer melt, while the latter occurs mainly in polymer solution. Correspondingly, the “row nuclei” for melt and “shish” for solution should be restricted to their initial definition and not be interchangeable, as molecular pictures of them are indeed different.