Rheology elasticity determined by deformation of stretchable molecular trains

Abstract

The average stretching direction, local rotation angular, and stretching ratio parameters of molecular trains were used to express the rheology deformation. Based on this micro geometrical deformation, the macro deformation of medium was expressed. Then, using intrinsic elasticity concept, the stress—strain relation was obtained. In this theoretic formulation, the response functions of extension ratio and rotation angular were used to express the rheology feature of medium. For medium composed by incompressible molecular trains, the local rotation angular divides rheology deformation into three kinds: viscoelastic deformation or elasticity enhancement, viscoplastic deformation or elasticity degenerate and constant elasticity range. These results explain the experimental features of rheology deformation well.

Keywords

viscoplasticity / viscoelasticity / local rotation angular / extension ratio / deformation tensor / rational mechanics / rheology

References

[1] DavidI. B.An introduction to polymer physics [M], 2002, Cambridge, Cambridge University Press

[2] TruesdellC.The mechanical foundation of elasticity and fluid mechanics [M], 1966, New York, Gordon and Breach Science Pub Inc

[3] ChenZ.-da.Rational mechanics [M], 1987, Xuzhou, China University of Mining and Technology Press

[4] XiaoJ.-h.. Decomposition of displacement gradient and strain definition [J]. Journal of Central South University of Technology, 2007, 14(s1): 401-404

[5] DunstanD. E., HillE. K., WeiY.. Direct measurement of polymer segment orientation and distortion in shear: Semi-dilute solution behavior [J]. Polymer, 2004, 45: 1261-1266