Effects of Molecular Mass and Stereo-Defect Distribution on the Crystallization and Morphological Behavior of β-Nucleated Isotactic Polypropylene

被引：0
|
作者：
Zhang Y. [1 ,2 ]
Jiang S. [3 ]
Li L. [2 ]
Kang J. [4 ]
机构：
[1] School of Civil Engineering, Chongqing Jiaotong University, Chongqing
[2] Chongqing Zhixiang Paving Technology Engineering Co., Ltd., Chongqing
[3] China Merchants Chongqing Communication Research & Design Institute Co., Ltd., Chongqing
[4] Polymer Research Institute of Sichuan University, State Key Laboratory of Polymer Materials Engineering, Chengdu
来源：
Li, Lu (61718494@qq.com) | 2017年 / Sichuan University卷 / 33期
关键词：
Isotactic polypropylene; Molecular mass; Stereo-defect distribution; β-crystallization;
D O I：
10.16865/j.cnki.1000-7555.2017.05.014
中图分类号：
学科分类号：
摘要：
In this study, the crystallization behavior and polymorphic morphology of two series of β-iPP resins with nearly same average isotacticity (PP-A and PP-B) but different uniformities of stereo-defect distribution, different molecular masses were investigated by differential scanning calorimetry (DSC), wide angle X-ray diffraction (WAXD) and scanning electron microscope (SEM). Results reveal that the uniformity of stereo-defect distribution plays determining role in the crystallization temperature of iPP, while both stereo-defect distribution uniformity and molecular masses are crucial factors affecting the crystallization efficiency and thermal stability of β-crystallization. Lower molecular mass and less uniform stereo-defect distribution are less favorable for formation of high amount of β-phase; the higher molecular mass and less uniform stereo-defect distribution help to form β-phase with higher thermal stability. Above results reveal that in the case of iPP nucleated with dual component β-nucleating agent, molecular masses and stereo-defect distribution play different roles in determining the polymorphic behavior of iPP, which should be considered comprehensively during the process of practical manufacturing and research. © 2017, Editorial Board of Polymer Materials Science & Engineering. All right reserved.
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页码：85 / 92
页数：7
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