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Flow Instabilities in Linear and Branched Syndiotactic Poly(propylene)s

✍ Scribed by Elena Rojo; Maria Eugenia Muñoz; Alexander Mateos; Anton Santamaría

Publisher
John Wiley and Sons
Year
2007
Tongue
English
Weight
204 KB
Volume
292
Category
Article
ISSN
1438-7492

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✦ Synopsis

Abstract

Extrusion flow experiments of linear and branched syndiotactic poly(propylene)s were carried out. The work was focused on flow instabilities. Ionized radiation was employed to induce long chain branching in linear samples. Sharkskin and melt fracture were postponed in the case of slightly long branched samples, which possess an enhanced melt elasticity compared to linear samples. For the most elastic samples the nature of the flow instability changed: sharkskin disappeared and melt fracture was observed instead. The correlation between sharkskin and melt strength results is discussed.

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