Crystal‐Like Bundles in Intrafibrillar Amorphous Regions and Nonlinear Viscoelasticity of Oriented Semicrystalline Polymers

A phenomenological model of the viscoelasticity of highly oriented polymer systems is developed on the basis of the results of studying the relaxation of such systems (e.g., fibers of polyethylene terephthalate, polyamide‐6, polyvinyl alcohol, and other polymers) in the loaded state. The effect of an applied load on their relaxation spectra agrees qualitatively with the deformation behavior of crystal‐like bundles that are present in amorphous intercrystalline layers of the long period fibrillar supermolecular structure.

Keywords:

• semicrystalline polymers
• mechanical properties
• nonlinear viscoelasticity
• relaxation spectra
• supermolecular organization

Acknowledgments

The authors are very grateful to Prof. P. H. Geil for helpful remarks and discussion. The authors are grateful also to Prof. D.A. Indeitsev for discussion of results. This work was carried out within the framework of the Program OE‐13 of fundamental researches of division of energetic, mechanical engineering, mechanics, and problems of control of the Russian Academy of Sciences.