Untersuchungen zur irreversibilität von Netzwerkentschlaufungen beim Fließen von Polymerschmelzen

✍ Scribed by Petra Ehrecke; Manfred H. Wagner

• Publisher: John Wiley and Sons
• Year: 1995
• Tongue: English
• Weight: 638 KB
• Volume: 196
• Category: Article
• ISSN: 1022-1352
• DOI: 10.1002/macp.1995.021960922

✦ Synopsis

Abstract

Experimental and theoretical investigations of stress relaxation after “double‐step” shear experiments lead to a better understanding of the irreversibility assumption of polymer melts. Here we compare measurements of shear stress relaxation for a branched polyethylene and a (linear) polyisobutene melt to theoretical predictions of Wagner's first and second equation and to a molecular theory of Doi. None of these theories is able to describe all the results of the measurements. These investigations demonstrate, however, what types of “double‐step” shear experiments are most sensitive to the irreversible disentanglement of polymer melts.