Huang, Qian1; Mednova, Olga3; Rasmussen, Henrik K.5; Javier Alvarez, Nicolas1; Skov, Anne Ladegaard7; Almdal, Kristoffer8; Hassager, Ole1
1 Department of Chemical and Biochemical Engineering, Technical University of Denmark2 The Danish Polymer Centre, Department of Chemical and Biochemical Engineering, Technical University of Denmark3 Department of Micro- and Nanotechnology, Technical University of Denmark4 Amphiphilic Polymers in Biological Sensing, Department of Micro- and Nanotechnology, Technical University of Denmark5 Department of Mechanical Engineering, Technical University of Denmark6 Manufacturing Engineering, Department of Mechanical Engineering, Technical University of Denmark7 Centre for oil and gas – DTU, Center, Technical University of Denmark8 Center for Nanostructured Graphene, Center, Technical University of Denmark
We compare viscoelastic properties of several polystyrene solutions and melts with the same number of entanglements. It is demonstrated that the modulus and time can be shifted such that the linear viscoelastic properties are identical provided the number of entanglements are identical. However the nonlinear properties in strong extensional flow are different with polymer solutions showing markedly stronger extensional hardening than the corresponding melts. While increased chain extensibility for solutions may provide part of the explanation, it is demonstrated that other mechanisms are needed for a full explanation for the differences between solutions and melts.