MULTISCALE MODELING OF THE VISCOELASTICITY OF A RUBBER ROD UNDER TENSILE DEFORMATION

N. G. MEDHIN

Title	MULTISCALE MODELING OF THE VISCOELASTICITY OF A RUBBER ROD UNDER TENSILE DEFORMATION
Publication Type	Journal Article
Year of Publication	2008
Authors	MEDHIN, NG
Volume	12
Issue	1
Start Page	1
Pagination	12
Date Published	2008
ISSN	1083-2564
Abstract	A molecular based model for the viscoelasticity of rubber is developed using a stickslip continuous molecular model. A corresponding nonlinear continuum model is given for tensile deformation. A linearized version of the model is studied for qualitative properties of the model. In our model cross-linked(CC)-system of molecules restrict the motion of entrapped or physically constrained(PC)-molecules. The dynamics of the PC-molecules is modeled by reptation in which the CC-molecules act as constraint boxes and the PC-molecules have to reptate in between the CC-molecules. We assume that a CC-unit cell is placed at each point of the rubber continuum with an entrapped PC-cell inside it. The deformation of the CC-cell causes a deformation of the PCsystem which relaxes after removal of the deformation. In the relaxation process the PC-molecules act as internal variables affecting the relaxation process of the CC-system. The Rouse model for relaxing polymers is incorporated into the stick-slip model presented by Johnson and Stacer [28] for describing the dynamics of the entrapped molecule for a short time right after instantaneous step-strain of the constraining CC-cell.
URL	http://www.acadsol.eu/en/articles/12/1/1.pdf
Refereed Designation	Refereed
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