Fracture behavior of bimodal polyethylene: Effect of molecular weight distribution characteristics
Fracture behavior of bimodal polyethylene: Effect of molecular weight distribution characteristics
复制标题
双峰聚乙烯的断裂行为：分子量分布特性的影响
DOI：
10.1016/j.polymer.2010.12.008
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发表时间：
2011-01-21
期刊：
影响因子：
4.6
通讯作者：
Yang, Mingbo
中科院分区：
文献类型：
--
作者：
Sun, Xin;Shen, Hongwang;Yang, Mingbo
通过熔融混合物制备了一系列具有不同分子量分布特征的双峰聚乙烯，并通过裂缝基本工作的方法研究了这些双峰聚乙烯的断裂行为。结果表明，裂缝的特定基本工作，我们显然会随着分子量分布的特征A（L/U）的形式增加，这表明提高了对裂纹传播的抗性。通过连续的自核和退火分析，发现双峰聚乙烯的晶体结构的明显变化，随着A（L/U）的增加。也就是说，随着（l/u）的增加，晶体尺寸和相对较厚的片状含量增加，但是尚未观察到晶体变化很大。因此，A（L/U）的影响主要对晶体完美，其改进会产生裂缝韧性的增强，因为在晶体区域和无定形区域构建的上层网络结构中会消散更多的能量。 （c）2010 Elsevier Ltd.保留所有权利。
A series of bimodal polyethylenes with different molecular weight distribution characteristics were prepared by melt blending, and the fracture behavior of these bimodal polyethylenes was studied by the method of essential work of fracture. The results show that specific essential work of fracture, We, increases obviously with the molecular weight distribution characteristic, A(L/U), indicating the improvement of the resistance to crack propagation. By means of successive self-nucleation and annealing analysis, obvious variations in the crystal structures of bimodal polyethylenes with increasing A(L/U) have been found. That is, the crystal size and the amount of relatively thick lamellas increase with A(L/U), but no large variation of crystallinities has been observed. So, the influence of A(L/U) is mainly on the crystal perfection, the improvement of which produces an enhancement of fracture toughness since more energy would be dissipated in the superior network structure constructed from crystalline zones and amorphous zones. (C) 2010 Elsevier Ltd. All rights reserved.