Paper Number
PL2 

Session
Plenary Lectures

Title
Rheology of ring polymer melts

Presentation Date and Time
October 16, 2018 (Tuesday) 8:30

Track / Room
Plenary Lectures / Galleria I

Authors (Click on name to view author profile)

  1. Rubinstein, Michael (Duke University, Mechanical Engineering and Materials Science)
  2. Ge, Ting (Duke University, Mechanical Engineering and Materials Science)
  3. Panyukov, Sergey (Russian Academy of Sciences)
  4. Grest, Gary S. (Sandia National Laboratories)
  5. Vlassopoulos, Dimitris (FORTH-IESL, Materials Science and Technology-University of Crete)

Author and Affiliation Lines (in printed abstract book)
Michael Rubinstein1, Ting Ge1, Sergey Panyukov2, Gary S. Grest3, and Dimitris Vlassopoulos4
1Mechanical Engineering and Materials Science, Duke University, Durham, NC 27710; 2Russian Academy of Sciences, Moscow, Russia; 3Sandia National Laboratories, Albuquerque, NM 87185; 4Materials Science and Technology-University of Crete, FORTH-IESL, HERAKLION, Greece

Speaker / Presenter 
Rubinstein, Michael

Text of Abstract
Some of the most interesting rheological features of polymer solutions and melts are due to entanglements between macromolecules. Entanglements between linear polymers as well as between branched polymers strongly affect dynamical properties of these materials, but do not affect equilibrium conformations of these molecules. A unique feature of cyclic polymers (rings) is that entanglements affect both their rheology and conformations. Topological interactions due to the non-concatenation condition compress ring molecules into fractal globules and force them to stay at marginal overlap with each other. Stress relaxation function of melts of ring polymers is a power law function of time without a rubbery plateau, reflecting unique self-similar dynamics of these molecules on different length and times scales. We introduce nanorheology as a method of obtaining relaxation modes of a polymer matrix from the mean square displacement of non-sticky nanoparticles and discuss the dependence of nanoparticle size on the modes obtained by this method for both linear and ring polymer melts. Mixing non-sticky nanoparticles with polymers can either increase or decrease the viscosity of this nanocomposite with respect to the viscosity of pure polymer melt. Shear rate dependence of viscosity of ring polymers is qualitatively different from shear thinning of linear polymers due to the absence of long-lived entanglements in ring polymer melts. Application of unique entanglement features of ring polymers to the elasticity of polymer networks and nuclear physics will be discussed.