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arXiv · 1609.02782

Solid-like rheological response of non-entangled polymers in the molten state

H Mendil·P Baroni·Laurence Noirez
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Abstract

We show that non-entangled polymers display an elastic-like behaviour at a macroscopic scale (probed at some 0.100 mm thickness) up to at least hundred degrees above the glass transition temperature. This observation, found under non-slippage conditions, both for side-chain liquid crystalline polymers and ordinary polymers, is in contradiction with the typically found flow behaviour of polymer melt. Our measurements were carried out with a conventional rheometer at thicknesses of several tenths millimetres. Thus, we were probing bulk properties. The observed elasticity supposedly implies that even in the melt the chains experience a cohesive effect of macroscopic distances, involving collective motions over time scales longer than the individual relaxation time of an individual polymer chain. The detection of such a solid-like property of molten non-entangled polymers is of considerable importance for a better understanding of the polymer dynamics.

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H Mendil, P Baroni, Laurence Noirez. 2016-09-09. Solid-like rheological response of non-entangled polymers in the molten state. https://doi.org/10.1140/epje%2Fe2006-00011-x

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