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arXiv · cond-mat/0201177

The nonlinear viscoelastic behavior of polypropylene

A. D. Drozdov·J. deC. Christiansen
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Abstract

A series of tensile relaxation tests is performed on isotactic polypropylene in the sub-yield and post-yield regions at room temperature. Constitutive equations are derived for the time-dependent response of a semicrystalline polymer at isothermal loading with small strains. Adjustable parameters in the stress-strain relations are found by fitting experimental data. It is demonstrated that the growth of the longitudinal strain results in an increase in the relaxation rate in a small interval of strains in the sub-yield domain. When the strain exceeds some critical value which is substantially less than the apparent yield strain, the relaxation process becomes strain-independent.

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A. D. Drozdov, J. deC. Christiansen. 2002-01-11. The nonlinear viscoelastic behavior of polypropylene. https://arxiv.org/abs/cond-mat/0201177

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