Paper Number
PM13 

Session
Polymer Melts: From Molecular Rheology to Processing

Title
Nonlinear shear rheometry of melts and concentrated solutions of polymers with varying molecular structure

Presentation Date and Time
October 16, 2018 (Tuesday) 5:00

Track / Room
Track 2 / Plaza I

Authors (Click on name to view author profile)

  1. Costanzo, Salvatore (Univ. of Montpellier)
  2. Parisi, Daniele (FORTH-IESL, Materials Science and Technology-University of Crete)
  3. Vlassopoulos, Dimitris (FORTH-IESL, Materials Science and Technology-University of Crete)

Author and Affiliation Lines (in printed abstract book)
Salvatore Costanzo1, Daniele Parisi2, and Dimitris Vlassopoulos3
1Univ. of Montpellier, Montpellier, France; 2Materials Science and Technology-University of Crete, FORTH-IESL, HERAKLION, Greece; 3Materials Science and Technology-University of Crete, FORTH-IESL, HERAKLION, Greece

Speaker / Presenter 
Vlassopoulos, Dimitris

Text of Abstract
We report on recent efforts to improve rheometric capabilities for polymer melts (mostly entangled but also some unentangled) and concentrated solutions. Using a modular cone-partitioned plate geometry it is relatively straightforward to determine shear stress, N1 and N2, over a wide range of Rouse-Weissenberg numbers, exceeding the value of 40, well into the stretching regime. For well-characterized linear polymers (mainly polystyrene) we identify stretching and tumbling regimes, compare with current state-of-the-art modeling and simulations, as well as with results from neutron scattering measurements with quenched samples at selected shear rates. With this background, we explore the effects of macromolecular architecture and address in particular the nonlinear shear rheology of star and ring polymers (again, well-characterized) and their mixtures with linear polymers. Particular emphasis is put on comparing with linear polymers, as well as existing predictions from theoretical modeling and simulations, focusing on scaling laws and the Cox-Merz rule.