Melt fracture of HDPEs: Metallocene versus Ziegler-Natta and broad MWD effects

被引:17
作者
Ansari, Mahmoud [1 ]
Inn, Yong W. [2 ]
Sukhadia, Ashish M. [2 ]
DesLauriers, Paul J. [2 ]
Hatzikiriakos, Savvas G. [1 ]
机构
[1] Univ British Columbia, Dept Chem & Biol Engn, Vancouver, BC V6T 1Z4, Canada
[2] Chevron Phillips Chem Co LP, Bartlesville, OK 74004 USA
关键词
Extrusion instabilities; Broad molecular weight distribution; Stick-slip; HIGH-DENSITY POLYETHYLENE; MOLECULAR-STRUCTURE; WALL SLIP; RHEOLOGICAL BEHAVIOR; CAPILLARY-FLOW; OSCILLATING FLOW; SHARKSKIN DEFECT; DEFORMATION; INSTABILITY; EXTRUSION;
D O I
10.1016/j.polymer.2012.07.030
中图分类号
O63 [高分子化学(高聚物)];
学科分类号
070305 ; 080501 ; 081704 ;
摘要
The melt fracture of high-density polyethylenes (HDPEs) is studied primarily as a function of molecular weight and its distribution for broad molecular weight distribution metallocene and Ziegler-Natta catalyst resins. It is found that sharkskin and other melt fracture phenomena are very different for these two classes of polymers, although their rheological behaviors are nearly the same for many of these. Moreover, the metallocene HDPE shows significant slip at the die wall without exhibiting stick-slip transition. Important correlations are derived between the critical conditions for the onset of melt fracture and molecular characteristics. (C) 2012 Elsevier Ltd. All rights reserved.
引用
收藏
页码:4195 / 4201
页数:7
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