The viscoelastic signature underpinning polymer deformation under shear flow

Research output: Contribution to journalArticle

Abstract

Entangled polymers are deformed by a strong shear flow. The shape of the polymer, called the form factor, is measured by small angle neutron scattering. However, the real-space molecular structure is not directly available from the reciprocal-space data, due to the phase problem. Instead, the data has to be fitted with a theoretical model of the molecule. We approximate the unknown structure using piecewise straight segments, from which we derive an analytical form factor. We fit it to our data on a semi-dilute entangled polystyrene solution under in situ shear flow. The character of the deformation is shown to lie between that of a single ideal chain (viscous) and a cross-linked network (elastic rubber). Furthermore, we use the fitted structure to estimate the mechanical stress, and find a fairly good agreement with rheology literature.

Details

Authors
  • Airidas Korolkovas
  • Sylvain Prévost
  • Maciej Kawecki
  • Anton Devishvili
  • Franz A. Adlmann
  • Philipp Gutfreund
  • Max Wolff
Organisations
External organisations
  • Institut Laue Langevin
  • Lund University
  • Uppsala University
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Physical Chemistry
Original languageEnglish
Pages (from-to)371-380
Number of pages10
JournalSoft Matter
Volume15
Issue number3
Publication statusPublished - 2019
Publication categoryResearch
Peer-reviewedYes