Dynamic shear flow and especially large-amplitude oscillatory shear have been a subject of interest to investigate limitations of theoretical approximations working under the assumption of simple shear. These studies have helped in understanding the kinematics involved in phenomena such as stick-slip and shear banding, among others. The nonequilibrium polymer melt, which transforms with time into the equilibrium state, provides a unique opportunity to investigate the influence of the thermodynamic melt state on the validity of simple shear approximations. Here, we show that during oscillatory deformation, the nonlinear rheological response of ultrahigh molecular weight polyethylene melts, having number-average molecular weight greater than one million g/mol, is strongly dependent on the entangled state of the same polymer. At sufficiently large strain amplitude, the stress response of the material departs from a periodic sinusoidal signal, with maximum stress decaying with consecutive cycles of deformation. A nonequilibrium polymer melt shows a faster decay in stress on consecutive application of oscillatory strain cycles, compared to its equilibrium state. These conclusions are supported by direct observation of the solid-liquid interface using a rheo-microscope device, where slippage appears to be the cause for the stress decay.
References
1.
Tapadia
P.
, S.
Ravindranath
, and S. Q.
Wang
, “Banding in entangled polymer fluids under oscillatory shearing
,” Phys. Rev. Lett.
96
, 196001
(2006
).2.
Agimelen
, O. S.
, and P.
Olmsted
, “Apparent fracture in polymeric fluids under step shear
,” Phys. Rev. Lett.
110
, 204503
(2013
).3.
Cao
, J.
, and A.
Likhtman
, “Shear banding in molecular dynamics of polymer melts
,” Phys. Rev. Lett.
108
, 028302
(2012
).4.
Auhl
, D.
, J.
Ramirez
, A. E.
Likhtman
, P.
Chambon
, and C.
Fernyhough
, “Linear and non-linear shear flow behavior of monodisperse polyisoprene melts with a large range of molecular weights
,” J. Rheol.
52
, 801
–835
(2008
).5.
Larson
, R. G.
, “Instabilities in viscoelastic flows
,” Rheol. Acta
31
, 213
–263
(1992
).6.
Denn
, M. M.
, “Extrusion instabilities and wall slip
,” Ann. Rev. Fluid Mech.
33
, 265
–287
(2001
).7.
Laun
, H. M.
, “Elastic properties of polyethylene melts at high shear rates with respect to extrusion
,” Rheol. Acta
21
, 464
–469
(1982
).8.
Hatzikiriakos
, S. G.
, and J. M.
Dealy
, “Wall slip of molten high density polyethylene. I. Sliding plate rheometer studies
,” J. Rheol.
35
, 497
–523
(1991
).9.
Kazatchkov
, I. B.
, and S. G.
Hatzikiriakos
, “Relaxation effects of slip in shear flow of linear molten polymers
,” Rheol. Acta
49
, 267
–274
(2010
).10.
Brochard
, F.
, and P. G.
de Gennes
, “Shear-dependant slippage at a polymer/solid interface
,” Langmuir
8
, 3033
–3037
(1992
).11.
Drda
, P. P.
, and S. Q.
Wang
, “Stick-slip transition at polymer melt/solid interfaces
,” Phys. Rev. Lett.
75
, 2698
–2701
(1995
).12.
Wang
, S. Q.
, and P. P.
Drda
, “Stick-slip transition in capillary flow of polyethylene 2. Molecular weight dependence and low-temperature anomaly
,” Macromolecules
29
, 4115
–4119
(1996
).13.
Hatzikiriakos
, S. G.
, “Wall slip of molten polymers
,” Prog. Polym. Sci.
37
, 624
–643
(2012
).14.
Rastogi
, S.
, Y.
Yao
, S.
Ronca
, J.
Bos
, and J.
van der Eem
, “Unprecedented high-modulus high-strength tapes and films of ultrahigh molecular weight polyethylene via solvent-free route
,” Macromolecules
44
, 5558
–5568
(2011
).15.
Ronca
, S.
, G.
Forte
, H.
Tjaden
, Y.
Yao
, and S.
Rastogi
, “Tailoring molecular structure via nanoparticles for solvent-free processing of ultra-high molecular weight polyethylene composites
,” Polymer
53
, 2897
–2907
(2012
).16.
Romano
, D.
, N.
Tops
, E. A.
Andablo-Reyes
, S.
Ronca
, and S.
Rastogi
, “Influence of polymerization conditions on melting kinetics of low entangled UHMWPE and its implications on mechanical properties
,” Macromolecules
47
, 4750
–4760
(2014
).17.
Yao
, Y.
, S.
Rastogi
, H. J.
Xue
, Q.
Chen
, R.
Graf
, and R.
Verhoef
, “Segmental mobility in the non-crystalline regions of nascent polyethylene synthesized using two different catalytic systems with implications on solid state deformation
,” Polymer
54
, 411
–422
(2013
).18.
Yao
, Y.
, S.
Jiang
, and S.
Rastogi
, “13C solid state NMR characterization of structure and orientation development in the narrow and broad molar mass disentangled UHWMPE
,” Macromolecules
47
, 1371
–1382
(2014
).19.
Pandey
, A.
, A.
Toda
, and S.
Rastogi
, “Influence of amorphous component on melting of semicrystalline polymers
,” Macromolecules
44
, 8042
–8055
(2011
).20.
Rastogi
, S.
, D. R.
Lippits
, G. W. H.
Hohne
, B.
Mezari
, and P. C. M. M.
Magusin
, “The role of the amorphous Phase in melting of linear UHMWPE; implications for chain dynamics
,” J. Phys.: Condens. Matter
19
, 205122
(2007
).21.
Lippits
, D. R.
, S.
Rastogi
, and G. W. H.
Höhne
, “Melting kinetics in polymers
,” Phys. Rev. Lett.
96
, 218303
(2006
).22.
Rastogi
, S.
, D.
Lippits
, G. W. M.
Peters
, R.
Graf
, Y.
Yao
, and H. W.
Spiess
, “Heterogeneity in polymer melts from melting of polymer crystals
,” Nat. Mater.
4
, 635
–641
(2005
).23.
Andablo-Reyes
, E. A.
, E. L.
de Boer
, D.
Romano
, and S.
Rastogi
, “Linear stress relaxation of nonequilibrium polymer melts
,” J. Rheol.
58
, 1981
–1991
(2014
).24.
Wilhelm
, M.
, D.
Maring
, and H. W.
Spiess
, “Fourier-transform rheology
,” Rheol. Acta
37
, 399
–405
(1998
).25.
Hyun
, K.
, S. H.
Kim
, K. H.
Ahn
, and S. J.
Lee
, “Large amplitude oscillatory shear as a way to classify the complex fluids
,” J. Non-Newtonian Fluid Mech.
107
, 51
–65
(2002
).26.
Li
, W. H.
, H.
Du
, G.
Chen
, S. H.
Yeo
, and N.
Guo
, “Nonlinear viscoelastic properties of MR fluids under large-amplitude-oscillatory-shear
,” Rheol. Acta
42
, 280
–286
(2003
).27.
Ewoldt
, R. H.
, P.
Winter
, J.
Maxey
, and G. H.
McKinley
, “Large amplitude oscillatory shear of pseudoplastic and elastoviscoplastic materials
,” Rheol. Acta
49
, 191
–202
(2010
).28.
Struth
, B.
, K.
Hyun
, E.
Kats
, T.
Meins
, M.
Walther
, M.
Wilhelm
, and G.
Grübel
, “Observation of new states of liquid crystal 8CB under nonlinear shear conditions as observed via a novel and unique rheology/small-angle X-ray scattering combination
,” Langmuir
27
, 2880
–2887
(2011
).29.
Kamble
, S.
, A.
Pandey
, S.
Rastogi
, and A.
Lele
, “Ascertaining universal features of yielding of soft materials
,” Rheol. Acta
52
, 859
–865
(2013
).30.
Kim
, J.
, D.
Merger
, M.
Wilhelm
, and M. E.
Helgeson
, “Microstructure and nonlinear signatures of yielding in a heterogeneous colloidal gel under large amplitude oscillatory shear
,” J. Rheol.
58
, 1359
–1390
(2014
).31.
Giacomin
, A. J.
, R. B.
Bird
, L. M.
Johnson
, and A. W.
Mix
, “Large-amplitude oscillatory shear flow from the corotational Maxwell model
,” J. Non-Newtonian Fluid Mech.
166
, 1081
–1099
(2011
).32.
Saengow
, C.
, A. J.
Giacomin
, and C.
Kolitawong
, “Exact analytical solution for large-amplitude oscillatory shear flow
,” Macromol. Theory Simulat.
24
, 352
–392
(2015
).33.
Bird
, R. B.
, R. C.
Armstrong
, O.
Hassager
, and C. F.
Curtiss
, Dynamics of Polymeric Liquids
(Wiley
, New York
, 1977
), Vol. 1
, p. 210
.34.
Ewoldt
, R. H.
, A. E.
Hosoi
, and G. H.
McKinley
, “New measures for characterizing nonlinear viscoelasticity in large amplitude oscillatory shear
,” J. Rheol.
52
, 1427
–1458
(2008
).35.
Hyun
, K.
, E. S.
Baik
, K. H.
Ahn
, S. J.
Lee
, M.
Sugimoto
, and K.
Koyama
, “Fourier-transform rheology under medium amplitude oscillatory shear for linear and branched polymer melts
,” J. Rheol.
51
, 1319
–1342
(2007
).36.
Hyun
, K.
, and M.
Wilhelm
, “Establishing a new mechanical nonlinear coefficient Q from FT-rheology: First investigation of entangled linear and comb polymer model systems
,” Macromolecules
42
, 411
–422
(2008
).37.
Hyun
, K.
, M.
Wilhelm
, C. O.
Klein
, K. S.
Cho
, J. G.
Nam
, K. H.
Ahn
, S. J.
Lee
, R. H.
Ewoldt
, and G. H.
McKinley
, “A review of nonlinear oscillatory shear tests: Analysis and application of large amplitude oscillatory shear (LAOS)
,” Prog. Polym. Sci.
36
, 1697
–1753
(2011
).38.
Hoyle
, D. M.
, D.
Auhl
, O. G.
Harlen
, V. C.
Barroso
, M.
Wilhelm
, and T. C. B.
McLeish
, “Large amplitude oscillatory shear and Fourier transform rheology analysis of branched polymer melts
,” J. Rheol.
58
, 969
–997
(2014
).39.
Mermet-Guyennet
, M. R. B.
, J. G.
de Castro
, M.
Habibi
, N.
Martzel
, M. M.
Denn
, and D.
Bonn
, “LAOS: The strain softening/strain hardening paradox
,” J. Rheol.
59
, 21
–32
(2015
).40.
Ronca
, S.
, D.
Romano
, G.
Forte
, E. A.
Andablo-Reyes
, and S.
Rastogi
, “Improving the performance of a catalytic system for the synthesis of ultra high molecular weight polyethylene with a reduced number of entanglements
,” Adv. Polym. Technol.
31
, 193
–204
(2012
).41.
Romano
, D.
, E. A.
Andablo-Reyes
, S.
Ronca
, and S.
Rastogi
, “Effect of a cocatalyst modifier in the synthesis of ultrahigh molecular weight polyethylene having reduced number of entanglements
,” J. Polym. Sci. Polym. Chem.
51
, 1630
–1635
(2013
).42.
Mead
, D. W.
, “Determination of molecular weight distributions of linear flexible polymers from linear viscoelastic material functions
,” J. Rheol.
38
, 1797
–1827
(1994
).43.
Talebi
, S.
, R.
Duchateau
, S.
Rastogi
, J.
Kaschta
, G. W. M.
Peters
, and P. J.
Lemstra
, “Molar mass and molecular weight determination of UHMWPE synthesized using a living homogenous catalyst
,” Macromolecules
43
, 2780
–2788
(2010
).44.
Pandey
, A.
, Y.
Champouret
, and S.
Rastogi
, “Heterogeneity in the distribution of entanglement density during polymerization in disentangled ultrahigh molecular weight polyethylene
,” Macromolecules
44
, 4952
–4960
(2011
).45.
See supplementary material at http://dx.doi.org/10.1122/1.4979334 for details on the thermal stability of polymer melts during frequency sweep tests and rheo-optical data to address the occurrence of slippage during oscillatory tests.
46.
Pandey
, A.
, S.
Rastogi
, G. W. M.
Peters
, and R.
Singh
, “Process for the melt extrusion of ultra-high molecular weight polyethylene
,” Report No. WO2013034582 A1
(2013
).© 2017 The Society of Rheology.
2017
The Society of Rheology
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