Non-linear Viscoelastic Behavior of PVC Plastisol

N. Nakajima; E. R. Harrell

doi:10.3139/217.1861

Article

Non-linear Viscoelastic Behavior of PVC Plastisol

N. Nakajima and E. R. Harrell

Published/Copyright: April 30, 2013

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From the journal International Polymer Processing Volume 20 Issue 1

Abstract

Rheology of PVC plastisol is usually conducted with steady state flow. It is inadequate, because plastisol is viscoelastic, so that deformational experiment is also required. In the viscoelastic measurements, when either frequency or amplitude is increased, dynamic viscosity decreases first (pseudo-plastic), reaching a minimum and then, increases (dilatant). It is because the shear rate during the oscillation is a product of frequency and amplitude. The pseudo-plastic behavior is explained with stress-induced phase separation into an immobilized layer of packed particles and mobile phase of reduced particle concentration. The viscosity minimum corresponds to the yield point of the immobilized layer. The yielding obeys Coulomb's criterion. After yielding the immobilized layer dilates with the further increase of shear rate. Two different modes of fracture are observed; one without yielding occurs at rather low shear stress, slightly higher than the cohesive strength of the immobilized layer. After yielding and dilation, the fracture occurs when shear stress becomes higher than normal stress. Before yielding the deformation of the immobilized layer is very small and accompanied with small fraction of particles moving over the neighboring particles. After yielding, deformation involves entire particles of the immobilized layer.

∗ Mail address: N. Nakajima, Inst. of Polym. Eng., University of Akron, 250 South Forge Street, Akron, OH 44325-0301, USA E-mail: nakajem@uakron.edu

References

1 Brookfield Rheometer, Brookfield Engineering Laboratories Inc. Cushing Street, Stoughton, MA 02072, ASTM D1824.Search in Google Scholar

2 Severs Rheometer, ASTM D1823.Search in Google Scholar

3 Nakajima, N., Daniels, C. A.: J. Appl. Polym. Sci.25, p. 2019 (1980).10.1002/app.1980.070250918Search in Google Scholar

4 Shikata, H., Pearson, D. S.: J. Rheol.38, p. 601 (1994).10.1122/1.550477Search in Google Scholar

5 Geon Vinyl, Dispersion Resins, Bulletin G-52, PolyOne Corporation.Search in Google Scholar

6 Cox, W. P., Merz, E. H.: J. Polym. Sci.28, p. 619 (1958).10.1002/pol.1958.1202811812Search in Google Scholar

7 Nakajima, N., Harrell, E. R.: J. Colloid and Interface Sci.254, p. 362 (2002).10.1006/jcis.2002.8517Search in Google Scholar PubMed

8 Ferry, J. D.: Viscoelastic Properties of Polymers. Wiley, New York (1980).Search in Google Scholar

9 Nakajima, N., Harrell, E. R.: Colloid and Interface Sci.238, p. 116 (2001).10.1006/jcis.2001.7469Search in Google Scholar PubMed

10 Johnston, C. W., Brower, C. H.: SPE ANTEC Tech. Papers26, p. 31 (1970).Search in Google Scholar

11 Nakajima, N., Harrell, E. R.: J. Colloid and Interface Sci.241, p. 492 (2001).10.1006/jcis.2001.7733Search in Google Scholar

12 Nakajima, N., Harrell, E. R.: J. Colloid and Interface Sci.241, p. 497 (2001).10.1006/jcis.2001.7734Search in Google Scholar

13 Coulomb, C. A.: Mem. Math. Phys.7, p. 343 (1773).Search in Google Scholar

14 Nakajima, N., Harrell, E. R.: J. Colloid and Interface Sci.254, p. 367 (2002).10.1006/jcis.2002.8518Search in Google Scholar PubMed

15 Hoffman, R. L.: Trans. Soc. Rheol.16, p. 155 (1972).10.1122/1.549250Search in Google Scholar

Received: 2004-1-13

Accepted: 2004-12-22

Published Online: 2013-04-30

Published in Print: 2005-03-01

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