Hostname: page-component-7c8c6479df-fqc5m Total loading time: 0 Render date: 2024-03-28T17:03:18.867Z Has data issue: false hasContentIssue false

Mechanism of aging effects on viscoelasticity in ethylene-methacrylic acid ionomer studied by local thermal-mechanical analysis

Published online by Cambridge University Press:  31 January 2011

Harsha P. Kulkarni
Affiliation:
Department of Physics and Astronomy and Curriculum in Applied and Materials Sciences, University of North Carolina, Chapel Hill, North Carolina 27599-3255
Gregory Mogilevsky
Affiliation:
Department of Physics and Astronomy and Curriculum in Applied and Materials Sciences, University of North Carolina, Chapel Hill, North Carolina 27599-3255
William M. Mullins
Affiliation:
Department of Mathematics, University of North Carolina, Chapel Hill, North Carolina 27599-3255
Yue Wu*
Affiliation:
Department of Physics and Astronomy and Curriculum in Applied and Materials Sciences, University of North Carolina, Chapel Hill, North Carolina 27599-3255
*
a) Address all correspondence to this author. e-mail: yuewu@physics.unc.edu
Get access

Abstract

A unique atomic force microscope-based local thermal-mechanical analysis (LTA) technique was used to study the influence of room temperature aging on viscoelastic properties of ethylene-methacrylic (E/MAA) acid ionomers. This approach permits easy access to structural relaxation effects on viscoelasticity at a short aging time, for instance, before the occurrence of secondary crystallization differential scanning calorimetry (DSC) melting peak. A Burger model along with finite element method yields quantitative analysis of viscoelastic properties versus the aging time. Creep curves were obtained with LTA after various times of aging at room temperature upon cooling from the melt. Measurements were carried out at both 30 and 70 °C. The results reveal the effects of structural relaxation upon aging in the ion-rich amorphous region, the influence of secondary crystallites on the viscoelastic properties, and shed light on the processes associated with aging in E/MAA ionomers.

Type
Articles
Copyright
Copyright © Materials Research Society 2009

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1.Eisenberg, A. and Kim, J.S.: Introduction to Ionomers (Wiley-Interscience, New York, 1998).Google Scholar
2.Vanhoorne, P. and Register, R.A.: Low-shear melt rheology of partially-neutralized ethylene-methacrylic acid ionomers. Macro-molecules 29, 598 (1996).Google Scholar
3.Hirasawa, E., Yamamoto, Y., Tadano, K., and Yano, S.: Formation of ionic crystallites and its effect on the modulus of ethylene ionomers. Macromolecules 22, 2776 (1989).Google Scholar
4.Wouters, M.E.L., Litvinov, V.M., Binsbergen, F.L., Goossens, J.G.P., Van Duin, M., and Dikland, H.G.: Morphology of ethylene-propylene copolymer based ionomers as studied by solid state NMR and small angle x-ray scattering in relation to some mechanical properties. Macromolecules 36, 1147 (2003).Google Scholar
5.Eisenberg, A.: Clustering of ions in organic polymers. A theoretical approach. Macromolecules 3, 147 (1970).Google Scholar
6.Bonotto, S. and Bonner, E.F.: Effect of ion valency on the bulk physical properties of salts of ethylene-acrylic acid copolymers. Macromolecules 1, 510 (1968).Google Scholar
7.Fall, R.: Puncture reversal of ethylene ionomers-mechanistic studies. Masters Thesis, Virginia Polytechnic Institute and State University, Blacksburg, VA, 2001.Google Scholar
8.Jia, Y., Kleinhammes, A., and Wu, Y.: NMR study of structure and dynamics of ionic multiplets in ethylene-methacrylic acid ionomers. Macromolecules 38, 2781 (2005).Google Scholar
9.Huber, A. and Hinkley, J.A.: Impression testing of self healing polymers. NASA/TM-2005–213532 (2005).Google Scholar
10.Akimoto, H., Kanazawa, T., Yamada, M., Matsuda, S., Shonaike, G.O., and Murakami, A.: Impact fracture behavior of ethylene ionomer and structural change after stretching. J. Appl. Polym. Sci. 81, 1712 (2001).Google Scholar
11.Hirasawa, E., Yamamoto, Y., Tadano, K., and Yano, S.: Effect of metal cation type on the structure and properties of ethylene ionomers. J. Appl. Polym. Sci. 42, 351 (1991).Google Scholar
12.Loo, Y., Wakabayashi, K., Huang, Y., Register, R., and Hsiao, B.: Thin crystal melting produces the low-temperature endotherm in ethylene/methacrylic acid ionomers. Polymer (Guildf.) 46, 5118 (2005).Google Scholar
13.Wakabayashi, K. and Register, R.A.: Morphological origin of the multistep relaxation behavior in semicrystalline ethylene/methacrylic acid ionomers. Macromolecules 39, 1079 (2006).Google Scholar
14.Eisenberg, A., Hird, B., and Moore, R.B.: A new multiplet-cluster model for the morphology of random ionomers. Macromolecules 23, 4098 (1990).Google Scholar
15.Riande, E., Diaz-Calleja, R., Prolongo, M., Masegosa, M.R., and Salom, C.: Polymer Viscoelasticity: Stress and Strain in Practice (Marcel Dekker Inc., New York, 2000), p. 404.Google Scholar
16.Gobet, F., Ciliberto, S., and Dauxois, T.: Aging phenomena in nonlinear dissipative chains. Eur. Phys. J. B. 34, 193 (2003).Google Scholar
17.Wang, H., Thompson, D.G., Schoonover, J.R., Aubuchon, S.R., and Palmer, R.A.: DMA-FTIR creep-recovery study of a poly (ester urethane) elastomer with molecular-level viscoelastic modeling. Macromolecules 34, 7084 (2001).Google Scholar
18.Dhondt, G.: The Finite Element Method for Three Dimensional Mechanical Applications (Wiley, 2004).Google Scholar
19.Tachino, H., Hara, H., Hirasawa, E., Kutsumizu, S., Tadano, K., and Yano, S.: Dynamic mechanical relaxations of ethylene ionomers. Macromolecules 26, 752 (1993).Google Scholar